[v2,1/3] net: Add support for Broadcom GENETv5 Ethernet controller

Message ID 20200117012047.31096-2-andre.przywara@arm.com
State Superseded
Headers show
Series
  • Ethernet support for Raspberry Pi 4
Related show

Commit Message

Andre Przywara Jan. 17, 2020, 1:20 a.m.
From: Amit Singh Tomar <amittomer25 at gmail.com>

The Broadcom GENET Ethernet MACs are used in several MIPS based SoCs
and in the Broadcom 2711/2838 SoC used on the Raspberry Pi 4.
There is no publicly available documentation, so this driver is based
on the Linux driver. Compared to that the queue management is
drastically simplified, also we only support version 5 of the IP and
RGMII connections between MAC and PHY, as used on the RPi4.

Signed-off-by: Amit Singh Tomar <amittomer25 at gmail.com>
Reviewed-by: Andre Przywara <andre.przywara at arm.com>
[Andre: heavy cleanup and a few fixes]
Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
 drivers/net/Kconfig    |   7 +
 drivers/net/Makefile   |   1 +
 drivers/net/bcmgenet.c | 722 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 730 insertions(+)
 create mode 100644 drivers/net/bcmgenet.c

Comments

Matthias Brugger Jan. 22, 2020, 9:01 a.m. | #1
On 17/01/2020 02:20, Andre Przywara wrote:
> From: Amit Singh Tomar <amittomer25 at gmail.com>
> 
> The Broadcom GENET Ethernet MACs are used in several MIPS based SoCs
> and in the Broadcom 2711/2838 SoC used on the Raspberry Pi 4.
> There is no publicly available documentation, so this driver is based
> on the Linux driver. Compared to that the queue management is
> drastically simplified, also we only support version 5 of the IP and
> RGMII connections between MAC and PHY, as used on the RPi4.
> 
> Signed-off-by: Amit Singh Tomar <amittomer25 at gmail.com>
> Reviewed-by: Andre Przywara <andre.przywara at arm.com>
> [Andre: heavy cleanup and a few fixes]
> Signed-off-by: Andre Przywara <andre.przywara at arm.com>

Tested-by: Matthias Brugger <mbrugger at suse.com>

Joe, are you planning to take this driver through your tree?

Regards,
Matthias

> ---
>  drivers/net/Kconfig    |   7 +
>  drivers/net/Makefile   |   1 +
>  drivers/net/bcmgenet.c | 722 +++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 730 insertions(+)
>  create mode 100644 drivers/net/bcmgenet.c
> 
> diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
> index 01d087f229..4d1013c984 100644
> --- a/drivers/net/Kconfig
> +++ b/drivers/net/Kconfig
> @@ -136,6 +136,13 @@ config BCM6368_ETH
>  	help
>  	  This driver supports the BCM6368 Ethernet MAC.
>  
> +config BCMGENET
> +	bool "BCMGENET V5 support"
> +	depends on DM_ETH
> +	select PHYLIB
> +	help
> +	  This driver supports the BCMGENET Ethernet MAC.
> +
>  config DWC_ETH_QOS
>  	bool "Synopsys DWC Ethernet QOS device support"
>  	depends on DM_ETH
> diff --git a/drivers/net/Makefile b/drivers/net/Makefile
> index 30991834ec..6e0a68834d 100644
> --- a/drivers/net/Makefile
> +++ b/drivers/net/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_AG7XXX) += ag7xxx.o
>  obj-$(CONFIG_ARMADA100_FEC) += armada100_fec.o
>  obj-$(CONFIG_BCM6348_ETH) += bcm6348-eth.o
>  obj-$(CONFIG_BCM6368_ETH) += bcm6368-eth.o
> +obj-$(CONFIG_BCMGENET) += bcmgenet.o
>  obj-$(CONFIG_DRIVER_AT91EMAC) += at91_emac.o
>  obj-$(CONFIG_DRIVER_AX88180) += ax88180.o
>  obj-$(CONFIG_BCM_SF2_ETH) += bcm-sf2-eth.o
> diff --git a/drivers/net/bcmgenet.c b/drivers/net/bcmgenet.c
> new file mode 100644
> index 0000000000..4f8f190071
> --- /dev/null
> +++ b/drivers/net/bcmgenet.c
> @@ -0,0 +1,722 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2019 Amit Singh Tomar <amittomer25 at gmail.com>
> + *
> + * Driver for Broadcom GENETv5 Ethernet controller (as found on the RPi4)
> + * This driver is based on the Linux driver:
> + *      drivers/net/ethernet/broadcom/genet/bcmgenet.c
> + *      which is: Copyright (c) 2014-2017 Broadcom
> + *
> + * The hardware supports multiple queues (16 priority queues and one
> + * default queue), both for RX and TX. There are 256 DMA descriptors (both
> + * for TX and RX), and they live in MMIO registers. The hardware allows
> + * assigning descriptor ranges to queues, but we choose the most simple setup:
> + * All 256 descriptors are assigned to the default queue (#16).
> + * Also the Linux driver supports multiple generations of the MAC, whereas
> + * we only support v5, as used in the Raspberry Pi 4.
> + */
> +
> +#include <asm/io.h>
> +#include <clk.h>
> +#include <cpu_func.h>
> +#include <dm.h>
> +#include <fdt_support.h>
> +#include <linux/err.h>
> +#include <malloc.h>
> +#include <miiphy.h>
> +#include <net.h>
> +#include <dm/of_access.h>
> +#include <dm/ofnode.h>
> +#include <linux/iopoll.h>
> +#include <linux/sizes.h>
> +#include <asm/dma-mapping.h>
> +#include <wait_bit.h>
> +
> +/* Register definitions derived from Linux source */
> +#define SYS_REV_CTRL			0x00
> +
> +#define SYS_PORT_CTRL			0x04
> +#define PORT_MODE_EXT_GPHY		3
> +
> +#define GENET_SYS_OFF			0x0000
> +#define SYS_RBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x08)
> +#define SYS_TBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x0c)
> +
> +#define GENET_EXT_OFF			0x0080
> +#define EXT_RGMII_OOB_CTRL		(GENET_EXT_OFF + 0x0c)
> +#define RGMII_LINK			BIT(4)
> +#define OOB_DISABLE			BIT(5)
> +#define RGMII_MODE_EN			BIT(6)
> +#define ID_MODE_DIS			BIT(16)
> +
> +#define GENET_RBUF_OFF			0x0300
> +#define RBUF_TBUF_SIZE_CTRL		(GENET_RBUF_OFF + 0xb4)
> +#define RBUF_CTRL			(GENET_RBUF_OFF + 0x00)
> +#define RBUF_ALIGN_2B			BIT(1)
> +
> +#define GENET_UMAC_OFF			0x0800
> +#define UMAC_MIB_CTRL			(GENET_UMAC_OFF + 0x580)
> +#define UMAC_MAX_FRAME_LEN		(GENET_UMAC_OFF + 0x014)
> +#define UMAC_MAC0			(GENET_UMAC_OFF + 0x00c)
> +#define UMAC_MAC1			(GENET_UMAC_OFF + 0x010)
> +#define UMAC_CMD			(GENET_UMAC_OFF + 0x008)
> +#define MDIO_CMD			(GENET_UMAC_OFF + 0x614)
> +#define UMAC_TX_FLUSH			(GENET_UMAC_OFF + 0x334)
> +#define MDIO_START_BUSY			BIT(29)
> +#define MDIO_READ_FAIL			BIT(28)
> +#define MDIO_RD				(2 << 26)
> +#define MDIO_WR				BIT(26)
> +#define MDIO_PMD_SHIFT			21
> +#define MDIO_PMD_MASK			0x1f
> +#define MDIO_REG_SHIFT			16
> +#define MDIO_REG_MASK			0x1f
> +
> +#define CMD_TX_EN			BIT(0)
> +#define CMD_RX_EN			BIT(1)
> +#define UMAC_SPEED_10			0
> +#define UMAC_SPEED_100			1
> +#define UMAC_SPEED_1000			2
> +#define UMAC_SPEED_2500			3
> +#define CMD_SPEED_SHIFT			2
> +#define CMD_SPEED_MASK			3
> +#define CMD_SW_RESET			BIT(13)
> +#define CMD_LCL_LOOP_EN			BIT(15)
> +#define CMD_TX_EN			BIT(0)
> +#define CMD_RX_EN			BIT(1)
> +
> +#define MIB_RESET_RX			BIT(0)
> +#define MIB_RESET_RUNT			BIT(1)
> +#define MIB_RESET_TX			BIT(2)
> +
> +/* total number of Buffer Descriptors, same for Rx/Tx */
> +#define TOTAL_DESCS			256
> +#define RX_DESCS			TOTAL_DESCS
> +#define TX_DESCS			TOTAL_DESCS
> +
> +#define DEFAULT_Q			0x10
> +
> +/* Body(1500) + EH_SIZE(14) + VLANTAG(4) + BRCMTAG(6) + FCS(4) = 1528.
> + * 1536 is multiple of 256 bytes
> + */
> +#define ENET_BRCM_TAG_LEN		6
> +#define ENET_PAD			8
> +#define ENET_MAX_MTU_SIZE		(ETH_DATA_LEN + ETH_HLEN +	 \
> +					 VLAN_HLEN + ENET_BRCM_TAG_LEN + \
> +					 ETH_FCS_LEN + ENET_PAD)
> +
> +/* Tx/Rx Dma Descriptor common bits */
> +#define DMA_EN				BIT(0)
> +#define DMA_RING_BUF_EN_SHIFT		0x01
> +#define DMA_RING_BUF_EN_MASK		0xffff
> +#define DMA_BUFLENGTH_MASK		0x0fff
> +#define DMA_BUFLENGTH_SHIFT		16
> +#define DMA_RING_SIZE_SHIFT		16
> +#define DMA_OWN				0x8000
> +#define DMA_EOP				0x4000
> +#define DMA_SOP				0x2000
> +#define DMA_WRAP			0x1000
> +#define DMA_MAX_BURST_LENGTH		0x8
> +/* Tx specific DMA descriptor bits */
> +#define DMA_TX_UNDERRUN			0x0200
> +#define DMA_TX_APPEND_CRC		0x0040
> +#define DMA_TX_OW_CRC			0x0020
> +#define DMA_TX_DO_CSUM			0x0010
> +#define DMA_TX_QTAG_SHIFT		7
> +
> +/* DMA rings size */
> +#define DMA_RING_SIZE			0x40
> +#define DMA_RINGS_SIZE			(DMA_RING_SIZE * (DEFAULT_Q + 1))
> +
> +/* DMA descriptor */
> +#define DMA_DESC_LENGTH_STATUS		0x00
> +#define DMA_DESC_ADDRESS_LO		0x04
> +#define DMA_DESC_ADDRESS_HI		0x08
> +#define DMA_DESC_SIZE			12
> +
> +#define GENET_RX_OFF			0x2000
> +#define GENET_RDMA_REG_OFF					\
> +	(GENET_RX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> +#define GENET_TX_OFF			0x4000
> +#define GENET_TDMA_REG_OFF					\
> +	(GENET_TX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> +
> +#define DMA_FC_THRESH_HI		(RX_DESCS >> 4)
> +#define DMA_FC_THRESH_LO		5
> +#define DMA_FC_THRESH_VALUE		((DMA_FC_THRESH_LO << 16) |	\
> +					  DMA_FC_THRESH_HI)
> +
> +#define DMA_XOFF_THRESHOLD_SHIFT	16
> +
> +#define TDMA_RING_REG_BASE					\
> +	(GENET_TDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> +#define TDMA_READ_PTR			(TDMA_RING_REG_BASE + 0x00)
> +#define TDMA_CONS_INDEX			(TDMA_RING_REG_BASE + 0x08)
> +#define TDMA_PROD_INDEX			(TDMA_RING_REG_BASE + 0x0c)
> +#define DMA_RING_BUF_SIZE		0x10
> +#define DMA_START_ADDR			0x14
> +#define DMA_END_ADDR			0x1c
> +#define DMA_MBUF_DONE_THRESH		0x24
> +#define TDMA_FLOW_PERIOD		(TDMA_RING_REG_BASE + 0x28)
> +#define TDMA_WRITE_PTR			(TDMA_RING_REG_BASE + 0x2c)
> +
> +#define RDMA_RING_REG_BASE					\
> +	(GENET_RDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> +#define RDMA_WRITE_PTR			(RDMA_RING_REG_BASE + 0x00)
> +#define RDMA_PROD_INDEX			(RDMA_RING_REG_BASE + 0x08)
> +#define RDMA_CONS_INDEX			(RDMA_RING_REG_BASE + 0x0c)
> +#define RDMA_XON_XOFF_THRESH		(RDMA_RING_REG_BASE + 0x28)
> +#define RDMA_READ_PTR			(RDMA_RING_REG_BASE + 0x2c)
> +
> +#define TDMA_REG_BASE			(GENET_TDMA_REG_OFF + DMA_RINGS_SIZE)
> +#define RDMA_REG_BASE			(GENET_RDMA_REG_OFF + DMA_RINGS_SIZE)
> +#define DMA_RING_CFG			0x00
> +#define DMA_CTRL			0x04
> +#define DMA_SCB_BURST_SIZE		0x0c
> +
> +#define RX_BUF_LENGTH			2048
> +#define RX_TOTAL_BUFSIZE		(RX_BUF_LENGTH * RX_DESCS)
> +#define RX_BUF_OFFSET			2
> +
> +struct bcmgenet_eth_priv {
> +	char rxbuffer[RX_TOTAL_BUFSIZE] __aligned(ARCH_DMA_MINALIGN);
> +	void *mac_reg;
> +	void *tx_desc_base;
> +	void *rx_desc_base;
> +	int tx_index;
> +	int rx_index;
> +	int c_index;
> +	int phyaddr;
> +	u32 interface;
> +	u32 speed;
> +	struct phy_device *phydev;
> +	struct mii_dev *bus;
> +};
> +
> +static void bcmgenet_umac_reset(struct bcmgenet_eth_priv *priv)
> +{
> +	u32 reg;
> +
> +	reg = readl(priv->mac_reg + SYS_RBUF_FLUSH_CTRL);
> +	reg |= BIT(1);
> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> +	udelay(10);
> +
> +	reg &= ~BIT(1);
> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> +	udelay(10);
> +
> +	writel(0, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> +	udelay(10);
> +
> +	writel(0, priv->mac_reg + UMAC_CMD);
> +
> +	writel(CMD_SW_RESET | CMD_LCL_LOOP_EN, priv->mac_reg + UMAC_CMD);
> +	udelay(2);
> +	writel(0, priv->mac_reg + UMAC_CMD);
> +
> +	/* clear tx/rx counter */
> +	writel(MIB_RESET_RX | MIB_RESET_TX | MIB_RESET_RUNT,
> +	       priv->mac_reg + UMAC_MIB_CTRL);
> +	writel(0, priv->mac_reg + UMAC_MIB_CTRL);
> +
> +	writel(ENET_MAX_MTU_SIZE, priv->mac_reg + UMAC_MAX_FRAME_LEN);
> +
> +	/* init rx registers, enable ip header optimization */
> +	reg = readl(priv->mac_reg + RBUF_CTRL);
> +	reg |= RBUF_ALIGN_2B;
> +	writel(reg, (priv->mac_reg + RBUF_CTRL));
> +
> +	writel(1, (priv->mac_reg + RBUF_TBUF_SIZE_CTRL));
> +}
> +
> +static int bcmgenet_gmac_write_hwaddr(struct udevice *dev)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> +	uchar *addr = pdata->enetaddr;
> +	u32 reg;
> +
> +	reg = addr[0] << 24 | addr[1] << 16 | addr[2] << 8 | addr[3];
> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC0);
> +
> +	reg = addr[4] << 8 | addr[5];
> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC1);
> +
> +	return 0;
> +}
> +
> +static void bcmgenet_disable_dma(struct bcmgenet_eth_priv *priv)
> +{
> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL, DMA_EN);
> +	clrbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, DMA_EN);
> +
> +	writel(1, priv->mac_reg + UMAC_TX_FLUSH);
> +	udelay(10);
> +	writel(0, priv->mac_reg + UMAC_TX_FLUSH);
> +}
> +
> +static void bcmgenet_enable_dma(struct bcmgenet_eth_priv *priv)
> +{
> +	u32 dma_ctrl = (1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT)) | DMA_EN;
> +
> +	writel(dma_ctrl, priv->mac_reg + TDMA_REG_BASE + DMA_CTRL);
> +
> +	setbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, dma_ctrl);
> +}
> +
> +static int bcmgenet_gmac_eth_send(struct udevice *dev, void *packet, int length)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	void *desc_base = priv->tx_desc_base + priv->tx_index * DMA_DESC_SIZE;
> +	u32 len_stat = length << DMA_BUFLENGTH_SHIFT;
> +	ulong packet_aligned = rounddown((ulong)packet, ARCH_DMA_MINALIGN);
> +	u32 prod_index, cons;
> +	u32 tries = 100;
> +
> +	prod_index = readl(priv->mac_reg + TDMA_PROD_INDEX);
> +
> +	/* There is actually no reason for the rounding here, but the ARMv7
> +	 * implementation of flush_dcache_range() checks for aligned
> +	 * boundaries of the flushed range.
> +	 * Adjust them here to pass that check and avoid misleading messages.
> +	 */
> +	flush_dcache_range(packet_aligned,
> +			   packet_aligned + roundup(length, ARCH_DMA_MINALIGN));
> +
> +	len_stat |= 0x3F << DMA_TX_QTAG_SHIFT;
> +	len_stat |= DMA_TX_APPEND_CRC | DMA_SOP | DMA_EOP;
> +
> +	/* Set-up packet for transmission */
> +	writel(lower_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_LO));
> +	writel(upper_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_HI));
> +	writel(len_stat, (desc_base + DMA_DESC_LENGTH_STATUS));
> +
> +	/* Increment index and start transmission */
> +	if (++priv->tx_index >= TX_DESCS)
> +		priv->tx_index = 0;
> +
> +	prod_index++;
> +
> +	/* Start Transmisson */
> +	writel(prod_index, priv->mac_reg + TDMA_PROD_INDEX);
> +
> +	do {
> +		cons = readl(priv->mac_reg + TDMA_CONS_INDEX);
> +	} while ((cons & 0xffff) < prod_index && --tries);
> +	if (!tries)
> +		return -ETIMEDOUT;
> +
> +	return 0;
> +}
> +
> +/* Check whether all cache lines affected by an invalidate are within
> + * the buffer, to make sure we don't accidentally lose unrelated dirty
> + * data stored nearby.
> + * Alignment of the buffer start address will be checked in the implementation
> + * of invalidate_dcache_range().
> + */
> +static void invalidate_dcache_check(unsigned long addr, size_t size,
> +				    size_t buffer_size)
> +{
> +	size_t inval_size = roundup(size, ARCH_DMA_MINALIGN);
> +
> +	if (unlikely(inval_size > buffer_size))
> +		printf("WARNING: Cache invalidate area exceeds buffer size\n");
> +
> +	invalidate_dcache_range(addr, addr + inval_size);
> +}
> +
> +static int bcmgenet_gmac_eth_recv(struct udevice *dev,
> +				  int flags, uchar **packetp)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	void *desc_base = priv->rx_desc_base + priv->rx_index * DMA_DESC_SIZE;
> +	u32 prod_index = readl(priv->mac_reg + RDMA_PROD_INDEX);
> +	u32 length, addr;
> +
> +	if (prod_index == priv->c_index)
> +		return -EAGAIN;
> +
> +	length = readl(desc_base + DMA_DESC_LENGTH_STATUS);
> +	length = (length >> DMA_BUFLENGTH_SHIFT) & DMA_BUFLENGTH_MASK;
> +	addr = readl(desc_base + DMA_DESC_ADDRESS_LO);
> +
> +	invalidate_dcache_check(addr, length, RX_BUF_LENGTH);
> +
> +	/* To cater for the IP header alignment the hardware does.
> +	 * This would actually not be needed if we don't program
> +	 * RBUF_ALIGN_2B
> +	 */
> +	*packetp = (uchar *)(ulong)addr + RX_BUF_OFFSET;
> +
> +	return length - RX_BUF_OFFSET;
> +}
> +
> +static int bcmgenet_gmac_free_pkt(struct udevice *dev, uchar *packet,
> +				  int length)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +
> +	/* Tell the MAC we have consumed that last receive buffer. */
> +	priv->c_index = (priv->c_index + 1) & 0xFFFF;
> +	writel(priv->c_index, priv->mac_reg + RDMA_CONS_INDEX);
> +
> +	/* Forward our descriptor pointer, wrapping around if needed. */
> +	if (++priv->rx_index >= RX_DESCS)
> +		priv->rx_index = 0;
> +
> +	return 0;
> +}
> +
> +static void rx_descs_init(struct bcmgenet_eth_priv *priv)
> +{
> +	char *rxbuffs = &priv->rxbuffer[0];
> +	u32 len_stat, i;
> +	void *desc_base = priv->rx_desc_base;
> +
> +	priv->c_index = 0;
> +
> +	len_stat = (RX_BUF_LENGTH << DMA_BUFLENGTH_SHIFT) | DMA_OWN;
> +
> +	for (i = 0; i < RX_DESCS; i++) {
> +		writel(lower_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_LO);
> +		writel(upper_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_HI);
> +		writel(len_stat,
> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_LENGTH_STATUS);
> +	}
> +}
> +
> +static void rx_ring_init(struct bcmgenet_eth_priv *priv)
> +{
> +	writel(DMA_MAX_BURST_LENGTH,
> +	       priv->mac_reg + RDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> +
> +	writel(0x0, priv->mac_reg + RDMA_RING_REG_BASE + DMA_START_ADDR);
> +	writel(0x0, priv->mac_reg + RDMA_READ_PTR);
> +	writel(0x0, priv->mac_reg + RDMA_WRITE_PTR);
> +	writel(RX_DESCS * DMA_DESC_SIZE / 4 - 1,
> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_END_ADDR);
> +
> +	writel(0x0, priv->mac_reg + RDMA_PROD_INDEX);
> +	writel(0x0, priv->mac_reg + RDMA_CONS_INDEX);
> +	writel((RX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> +	writel(DMA_FC_THRESH_VALUE, priv->mac_reg + RDMA_XON_XOFF_THRESH);
> +	writel(1 << DEFAULT_Q, priv->mac_reg + RDMA_REG_BASE + DMA_RING_CFG);
> +}
> +
> +static void tx_ring_init(struct bcmgenet_eth_priv *priv)
> +{
> +	writel(DMA_MAX_BURST_LENGTH,
> +	       priv->mac_reg + TDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> +
> +	writel(0x0, priv->mac_reg + TDMA_RING_REG_BASE + DMA_START_ADDR);
> +	writel(0x0, priv->mac_reg + TDMA_READ_PTR);
> +	writel(0x0, priv->mac_reg + TDMA_WRITE_PTR);
> +	writel(TX_DESCS * DMA_DESC_SIZE / 4 - 1,
> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_END_ADDR);
> +	writel(0x0, priv->mac_reg + TDMA_PROD_INDEX);
> +	writel(0x0, priv->mac_reg + TDMA_CONS_INDEX);
> +	writel(0x1, priv->mac_reg + TDMA_RING_REG_BASE + DMA_MBUF_DONE_THRESH);
> +	writel(0x0, priv->mac_reg + TDMA_FLOW_PERIOD);
> +	writel((TX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> +
> +	writel(1 << DEFAULT_Q, priv->mac_reg + TDMA_REG_BASE + DMA_RING_CFG);
> +}
> +
> +static int bcmgenet_adjust_link(struct bcmgenet_eth_priv *priv)
> +{
> +	struct phy_device *phy_dev = priv->phydev;
> +	u32 speed;
> +
> +	switch (phy_dev->speed) {
> +	case SPEED_1000:
> +		speed = UMAC_SPEED_1000;
> +		break;
> +	case SPEED_100:
> +		speed = UMAC_SPEED_100;
> +		break;
> +	case SPEED_10:
> +		speed = UMAC_SPEED_10;
> +		break;
> +	default:
> +		printf("bcmgenet: Unsupported PHY speed: %d\n", phy_dev->speed);
> +		return -EINVAL;
> +	}
> +
> +	clrsetbits_32(priv->mac_reg + EXT_RGMII_OOB_CTRL, OOB_DISABLE,
> +			RGMII_LINK | RGMII_MODE_EN | ID_MODE_DIS);
> +
> +	writel(speed << CMD_SPEED_SHIFT, (priv->mac_reg + UMAC_CMD));
> +
> +	return 0;
> +}
> +
> +static int bcmgenet_gmac_eth_start(struct udevice *dev)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	int ret;
> +
> +	priv->tx_desc_base = priv->mac_reg + GENET_TX_OFF;
> +	priv->rx_desc_base = priv->mac_reg + GENET_RX_OFF;
> +	priv->tx_index = 0x0;
> +	priv->rx_index = 0x0;
> +
> +	bcmgenet_umac_reset(priv);
> +
> +	bcmgenet_gmac_write_hwaddr(dev);
> +
> +	/* Disable RX/TX DMA and flush TX queues */
> +	bcmgenet_disable_dma(priv);
> +
> +	rx_ring_init(priv);
> +	rx_descs_init(priv);
> +
> +	tx_ring_init(priv);
> +
> +	/* Enable RX/TX DMA */
> +	bcmgenet_enable_dma(priv);
> +
> +	/* read PHY properties over the wire from generic PHY set-up */
> +	ret = phy_startup(priv->phydev);
> +	if (ret) {
> +		printf("bcmgenet: PHY startup failed: %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* Update MAC registers based on PHY property */
> +	ret = bcmgenet_adjust_link(priv);
> +	if (ret) {
> +		printf("bcmgenet: adjust PHY link failed: %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* Enable Rx/Tx */
> +	setbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> +
> +	return 0;
> +}
> +
> +static int bcmgenet_phy_init(struct bcmgenet_eth_priv *priv, void *dev)
> +{
> +	struct phy_device *phydev;
> +	int ret;
> +
> +	phydev = phy_connect(priv->bus, priv->phyaddr, dev, priv->interface);
> +	if (!phydev)
> +		return -ENODEV;
> +
> +	phydev->supported &= PHY_GBIT_FEATURES;
> +	if (priv->speed) {
> +		ret = phy_set_supported(priv->phydev, priv->speed);
> +		if (ret)
> +			return ret;
> +	}
> +	phydev->advertising = phydev->supported;
> +
> +	phy_connect_dev(phydev, dev);
> +
> +	priv->phydev = phydev;
> +	phy_config(priv->phydev);
> +
> +	return 0;
> +}
> +
> +static void bcmgenet_mdio_start(struct bcmgenet_eth_priv *priv)
> +{
> +	setbits_32(priv->mac_reg + MDIO_CMD, MDIO_START_BUSY);
> +}
> +
> +static int bcmgenet_mdio_write(struct mii_dev *bus, int addr, int devad,
> +			       int reg, u16 value)
> +{
> +	struct udevice *dev = bus->priv;
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	u32 val;
> +
> +	/* Prepare the read operation */
> +	val = MDIO_WR | (addr << MDIO_PMD_SHIFT) |
> +		(reg << MDIO_REG_SHIFT) | (0xffff & value);
> +	writel_relaxed(val,  priv->mac_reg + MDIO_CMD);
> +
> +	/* Start MDIO transaction */
> +	bcmgenet_mdio_start(priv);
> +
> +	return wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> +			       MDIO_START_BUSY, false, 20, true);
> +}
> +
> +static int bcmgenet_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
> +{
> +	struct udevice *dev = bus->priv;
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	u32 val;
> +	int ret;
> +
> +	/* Prepare the read operation */
> +	val = MDIO_RD | (addr << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
> +	writel_relaxed(val, priv->mac_reg + MDIO_CMD);
> +
> +	/* Start MDIO transaction */
> +	bcmgenet_mdio_start(priv);
> +
> +	ret = wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> +			      MDIO_START_BUSY, false, 20, true);
> +	if (ret)
> +		return ret;
> +
> +	val = readl_relaxed(priv->mac_reg + MDIO_CMD);
> +
> +	return val & 0xffff;
> +}
> +
> +static int bcmgenet_mdio_init(const char *name, struct udevice *priv)
> +{
> +	struct mii_dev *bus = mdio_alloc();
> +
> +	if (!bus) {
> +		debug("Failed to allocate MDIO bus\n");
> +		return -ENOMEM;
> +	}
> +
> +	bus->read = bcmgenet_mdio_read;
> +	bus->write = bcmgenet_mdio_write;
> +	snprintf(bus->name, sizeof(bus->name), name);
> +	bus->priv = (void *)priv;
> +
> +	return mdio_register(bus);
> +}
> +
> +/* We only support RGMII (as used on the RPi4). */
> +static int bcmgenet_interface_set(struct bcmgenet_eth_priv *priv)
> +{
> +	phy_interface_t phy_mode = priv->interface;
> +
> +	switch (phy_mode) {
> +	case PHY_INTERFACE_MODE_RGMII:
> +	case PHY_INTERFACE_MODE_RGMII_RXID:
> +		writel(PORT_MODE_EXT_GPHY, priv->mac_reg + SYS_PORT_CTRL);
> +		break;
> +	default:
> +		printf("unknown phy mode: %d\n", priv->interface);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bcmgenet_eth_probe(struct udevice *dev)
> +{
> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	ofnode mdio_node;
> +	const char *name;
> +	u32 reg;
> +	int ret;
> +	u8 major;
> +
> +	priv->mac_reg = map_physmem(pdata->iobase, SZ_64K, MAP_NOCACHE);
> +	priv->interface = pdata->phy_interface;
> +	priv->speed = pdata->max_speed;
> +
> +	/* Read GENET HW version */
> +	reg = readl_relaxed(priv->mac_reg + SYS_REV_CTRL);
> +	major = (reg >> 24) & 0x0f;
> +	if (major != 6) {
> +		if (major == 5)
> +			major = 4;
> +		else if (major == 0)
> +			major = 1;
> +
> +		printf("Unsupported GENETv%d.%d\n", major, (reg >> 16) & 0x0f);
> +		return -ENODEV;
> +	}
> +
> +	ret = bcmgenet_interface_set(priv);
> +	if (ret)
> +		return ret;
> +
> +	mdio_node = dev_read_first_subnode(dev);
> +	name = ofnode_get_name(mdio_node);
> +
> +	ret = bcmgenet_mdio_init(name, dev);
> +	if (ret)
> +		return ret;
> +
> +	priv->bus = miiphy_get_dev_by_name(name);
> +
> +	return bcmgenet_phy_init(priv, dev);
> +}
> +
> +static void bcmgenet_gmac_eth_stop(struct udevice *dev)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +
> +	clrbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL,
> +		     1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT) | DMA_EN);
> +}
> +
> +static const struct eth_ops bcmgenet_gmac_eth_ops = {
> +	.start                  = bcmgenet_gmac_eth_start,
> +	.write_hwaddr           = bcmgenet_gmac_write_hwaddr,
> +	.send                   = bcmgenet_gmac_eth_send,
> +	.recv                   = bcmgenet_gmac_eth_recv,
> +	.free_pkt               = bcmgenet_gmac_free_pkt,
> +	.stop                   = bcmgenet_gmac_eth_stop,
> +};
> +
> +static int bcmgenet_eth_ofdata_to_platdata(struct udevice *dev)
> +{
> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	struct ofnode_phandle_args phy_node;
> +	const char *phy_mode;
> +	int ret;
> +
> +	pdata->iobase = dev_read_addr(dev);
> +
> +	/* Get phy mode from DT */
> +	pdata->phy_interface = -1;
> +	phy_mode = dev_read_string(dev, "phy-mode");
> +	if (phy_mode)
> +		pdata->phy_interface = phy_get_interface_by_name(phy_mode);
> +	if (pdata->phy_interface == -1) {
> +		debug("%s: Invalid PHY interface '%s'\n", __func__, phy_mode);
> +		return -EINVAL;
> +	}
> +
> +	ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
> +					 &phy_node);
> +	if (!ret) {
> +		ofnode_read_s32(phy_node.node, "reg", &priv->phyaddr);
> +		ofnode_read_s32(phy_node.node, "max-speed", &pdata->max_speed);
> +	}
> +
> +	return 0;
> +}
> +
> +/* The BCM2711 implementation has a limited burst length compared to a generic
> + * GENETv5 version, but we go with that shorter value (8) in both cases, for
> + * the sake of simplicity.
> + */
> +static const struct udevice_id bcmgenet_eth_ids[] = {
> +	{.compatible = "brcm,genet-v5"},
> +	{.compatible = "brcm,bcm2711-genet-v5"},
> +	{}
> +};
> +
> +U_BOOT_DRIVER(eth_bcmgenet) = {
> +	.name   = "eth_bcmgenet",
> +	.id     = UCLASS_ETH,
> +	.of_match = bcmgenet_eth_ids,
> +	.ofdata_to_platdata = bcmgenet_eth_ofdata_to_platdata,
> +	.probe  = bcmgenet_eth_probe,
> +	.ops    = &bcmgenet_gmac_eth_ops,
> +	.priv_auto_alloc_size = sizeof(struct bcmgenet_eth_priv),
> +	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
> +	.flags = DM_FLAG_ALLOC_PRIV_DMA,
> +};
>
Daniel Schwierzeck Jan. 22, 2020, 3:02 p.m. | #2
Am 17.01.20 um 02:20 schrieb Andre Przywara:
> From: Amit Singh Tomar <amittomer25 at gmail.com>
> 
> The Broadcom GENET Ethernet MACs are used in several MIPS based SoCs
> and in the Broadcom 2711/2838 SoC used on the Raspberry Pi 4.
> There is no publicly available documentation, so this driver is based
> on the Linux driver. Compared to that the queue management is
> drastically simplified, also we only support version 5 of the IP and
> RGMII connections between MAC and PHY, as used on the RPi4.
> 
> Signed-off-by: Amit Singh Tomar <amittomer25 at gmail.com>
> Reviewed-by: Andre Przywara <andre.przywara at arm.com>
> [Andre: heavy cleanup and a few fixes]
> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> ---
>  drivers/net/Kconfig    |   7 +
>  drivers/net/Makefile   |   1 +
>  drivers/net/bcmgenet.c | 722 +++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 730 insertions(+)
>  create mode 100644 drivers/net/bcmgenet.c

Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>

nits below

> 
> diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
> index 01d087f229..4d1013c984 100644
> --- a/drivers/net/Kconfig
> +++ b/drivers/net/Kconfig
> @@ -136,6 +136,13 @@ config BCM6368_ETH
>  	help
>  	  This driver supports the BCM6368 Ethernet MAC.
>  
> +config BCMGENET
> +	bool "BCMGENET V5 support"
> +	depends on DM_ETH

maybe this should be limited to the supported SoC's?

e.g.  depends on DM_ETH && ARCH_BCM283X

> +	select PHYLIB
> +	help
> +	  This driver supports the BCMGENET Ethernet MAC.
> +
>  config DWC_ETH_QOS
>  	bool "Synopsys DWC Ethernet QOS device support"
>  	depends on DM_ETH
> diff --git a/drivers/net/Makefile b/drivers/net/Makefile
> index 30991834ec..6e0a68834d 100644
> --- a/drivers/net/Makefile
> +++ b/drivers/net/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_AG7XXX) += ag7xxx.o
>  obj-$(CONFIG_ARMADA100_FEC) += armada100_fec.o
>  obj-$(CONFIG_BCM6348_ETH) += bcm6348-eth.o
>  obj-$(CONFIG_BCM6368_ETH) += bcm6368-eth.o
> +obj-$(CONFIG_BCMGENET) += bcmgenet.o
>  obj-$(CONFIG_DRIVER_AT91EMAC) += at91_emac.o
>  obj-$(CONFIG_DRIVER_AX88180) += ax88180.o
>  obj-$(CONFIG_BCM_SF2_ETH) += bcm-sf2-eth.o
> diff --git a/drivers/net/bcmgenet.c b/drivers/net/bcmgenet.c
> new file mode 100644
> index 0000000000..4f8f190071
> --- /dev/null
> +++ b/drivers/net/bcmgenet.c
> @@ -0,0 +1,722 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2019 Amit Singh Tomar <amittomer25 at gmail.com>
> + *
> + * Driver for Broadcom GENETv5 Ethernet controller (as found on the RPi4)
> + * This driver is based on the Linux driver:
> + *      drivers/net/ethernet/broadcom/genet/bcmgenet.c
> + *      which is: Copyright (c) 2014-2017 Broadcom
> + *
> + * The hardware supports multiple queues (16 priority queues and one
> + * default queue), both for RX and TX. There are 256 DMA descriptors (both
> + * for TX and RX), and they live in MMIO registers. The hardware allows
> + * assigning descriptor ranges to queues, but we choose the most simple setup:
> + * All 256 descriptors are assigned to the default queue (#16).
> + * Also the Linux driver supports multiple generations of the MAC, whereas
> + * we only support v5, as used in the Raspberry Pi 4.
> + */
> +
> +#include <asm/io.h>
> +#include <clk.h>
> +#include <cpu_func.h>
> +#include <dm.h>
> +#include <fdt_support.h>
> +#include <linux/err.h>
> +#include <malloc.h>
> +#include <miiphy.h>
> +#include <net.h>
> +#include <dm/of_access.h>
> +#include <dm/ofnode.h>
> +#include <linux/iopoll.h>
> +#include <linux/sizes.h>
> +#include <asm/dma-mapping.h>
> +#include <wait_bit.h>
> +
> +/* Register definitions derived from Linux source */
> +#define SYS_REV_CTRL			0x00
> +
> +#define SYS_PORT_CTRL			0x04
> +#define PORT_MODE_EXT_GPHY		3
> +
> +#define GENET_SYS_OFF			0x0000
> +#define SYS_RBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x08)
> +#define SYS_TBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x0c)
> +
> +#define GENET_EXT_OFF			0x0080
> +#define EXT_RGMII_OOB_CTRL		(GENET_EXT_OFF + 0x0c)
> +#define RGMII_LINK			BIT(4)
> +#define OOB_DISABLE			BIT(5)
> +#define RGMII_MODE_EN			BIT(6)
> +#define ID_MODE_DIS			BIT(16)
> +
> +#define GENET_RBUF_OFF			0x0300
> +#define RBUF_TBUF_SIZE_CTRL		(GENET_RBUF_OFF + 0xb4)
> +#define RBUF_CTRL			(GENET_RBUF_OFF + 0x00)
> +#define RBUF_ALIGN_2B			BIT(1)
> +
> +#define GENET_UMAC_OFF			0x0800
> +#define UMAC_MIB_CTRL			(GENET_UMAC_OFF + 0x580)
> +#define UMAC_MAX_FRAME_LEN		(GENET_UMAC_OFF + 0x014)
> +#define UMAC_MAC0			(GENET_UMAC_OFF + 0x00c)
> +#define UMAC_MAC1			(GENET_UMAC_OFF + 0x010)
> +#define UMAC_CMD			(GENET_UMAC_OFF + 0x008)
> +#define MDIO_CMD			(GENET_UMAC_OFF + 0x614)
> +#define UMAC_TX_FLUSH			(GENET_UMAC_OFF + 0x334)
> +#define MDIO_START_BUSY			BIT(29)
> +#define MDIO_READ_FAIL			BIT(28)
> +#define MDIO_RD				(2 << 26)
> +#define MDIO_WR				BIT(26)
> +#define MDIO_PMD_SHIFT			21
> +#define MDIO_PMD_MASK			0x1f
> +#define MDIO_REG_SHIFT			16
> +#define MDIO_REG_MASK			0x1f
> +
> +#define CMD_TX_EN			BIT(0)
> +#define CMD_RX_EN			BIT(1)
> +#define UMAC_SPEED_10			0
> +#define UMAC_SPEED_100			1
> +#define UMAC_SPEED_1000			2
> +#define UMAC_SPEED_2500			3
> +#define CMD_SPEED_SHIFT			2
> +#define CMD_SPEED_MASK			3
> +#define CMD_SW_RESET			BIT(13)
> +#define CMD_LCL_LOOP_EN			BIT(15)
> +#define CMD_TX_EN			BIT(0)
> +#define CMD_RX_EN			BIT(1)
> +
> +#define MIB_RESET_RX			BIT(0)
> +#define MIB_RESET_RUNT			BIT(1)
> +#define MIB_RESET_TX			BIT(2)
> +
> +/* total number of Buffer Descriptors, same for Rx/Tx */
> +#define TOTAL_DESCS			256
> +#define RX_DESCS			TOTAL_DESCS
> +#define TX_DESCS			TOTAL_DESCS
> +
> +#define DEFAULT_Q			0x10
> +
> +/* Body(1500) + EH_SIZE(14) + VLANTAG(4) + BRCMTAG(6) + FCS(4) = 1528.
> + * 1536 is multiple of 256 bytes
> + */
> +#define ENET_BRCM_TAG_LEN		6
> +#define ENET_PAD			8
> +#define ENET_MAX_MTU_SIZE		(ETH_DATA_LEN + ETH_HLEN +	 \
> +					 VLAN_HLEN + ENET_BRCM_TAG_LEN + \
> +					 ETH_FCS_LEN + ENET_PAD)
> +
> +/* Tx/Rx Dma Descriptor common bits */
> +#define DMA_EN				BIT(0)
> +#define DMA_RING_BUF_EN_SHIFT		0x01
> +#define DMA_RING_BUF_EN_MASK		0xffff
> +#define DMA_BUFLENGTH_MASK		0x0fff
> +#define DMA_BUFLENGTH_SHIFT		16
> +#define DMA_RING_SIZE_SHIFT		16
> +#define DMA_OWN				0x8000
> +#define DMA_EOP				0x4000
> +#define DMA_SOP				0x2000
> +#define DMA_WRAP			0x1000
> +#define DMA_MAX_BURST_LENGTH		0x8
> +/* Tx specific DMA descriptor bits */
> +#define DMA_TX_UNDERRUN			0x0200
> +#define DMA_TX_APPEND_CRC		0x0040
> +#define DMA_TX_OW_CRC			0x0020
> +#define DMA_TX_DO_CSUM			0x0010
> +#define DMA_TX_QTAG_SHIFT		7
> +
> +/* DMA rings size */
> +#define DMA_RING_SIZE			0x40
> +#define DMA_RINGS_SIZE			(DMA_RING_SIZE * (DEFAULT_Q + 1))
> +
> +/* DMA descriptor */
> +#define DMA_DESC_LENGTH_STATUS		0x00
> +#define DMA_DESC_ADDRESS_LO		0x04
> +#define DMA_DESC_ADDRESS_HI		0x08
> +#define DMA_DESC_SIZE			12
> +
> +#define GENET_RX_OFF			0x2000
> +#define GENET_RDMA_REG_OFF					\
> +	(GENET_RX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> +#define GENET_TX_OFF			0x4000
> +#define GENET_TDMA_REG_OFF					\
> +	(GENET_TX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> +
> +#define DMA_FC_THRESH_HI		(RX_DESCS >> 4)
> +#define DMA_FC_THRESH_LO		5
> +#define DMA_FC_THRESH_VALUE		((DMA_FC_THRESH_LO << 16) |	\
> +					  DMA_FC_THRESH_HI)
> +
> +#define DMA_XOFF_THRESHOLD_SHIFT	16
> +
> +#define TDMA_RING_REG_BASE					\
> +	(GENET_TDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> +#define TDMA_READ_PTR			(TDMA_RING_REG_BASE + 0x00)
> +#define TDMA_CONS_INDEX			(TDMA_RING_REG_BASE + 0x08)
> +#define TDMA_PROD_INDEX			(TDMA_RING_REG_BASE + 0x0c)
> +#define DMA_RING_BUF_SIZE		0x10
> +#define DMA_START_ADDR			0x14
> +#define DMA_END_ADDR			0x1c
> +#define DMA_MBUF_DONE_THRESH		0x24
> +#define TDMA_FLOW_PERIOD		(TDMA_RING_REG_BASE + 0x28)
> +#define TDMA_WRITE_PTR			(TDMA_RING_REG_BASE + 0x2c)
> +
> +#define RDMA_RING_REG_BASE					\
> +	(GENET_RDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> +#define RDMA_WRITE_PTR			(RDMA_RING_REG_BASE + 0x00)
> +#define RDMA_PROD_INDEX			(RDMA_RING_REG_BASE + 0x08)
> +#define RDMA_CONS_INDEX			(RDMA_RING_REG_BASE + 0x0c)
> +#define RDMA_XON_XOFF_THRESH		(RDMA_RING_REG_BASE + 0x28)
> +#define RDMA_READ_PTR			(RDMA_RING_REG_BASE + 0x2c)
> +
> +#define TDMA_REG_BASE			(GENET_TDMA_REG_OFF + DMA_RINGS_SIZE)
> +#define RDMA_REG_BASE			(GENET_RDMA_REG_OFF + DMA_RINGS_SIZE)
> +#define DMA_RING_CFG			0x00
> +#define DMA_CTRL			0x04
> +#define DMA_SCB_BURST_SIZE		0x0c
> +
> +#define RX_BUF_LENGTH			2048
> +#define RX_TOTAL_BUFSIZE		(RX_BUF_LENGTH * RX_DESCS)
> +#define RX_BUF_OFFSET			2
> +
> +struct bcmgenet_eth_priv {
> +	char rxbuffer[RX_TOTAL_BUFSIZE] __aligned(ARCH_DMA_MINALIGN);
> +	void *mac_reg;
> +	void *tx_desc_base;
> +	void *rx_desc_base;
> +	int tx_index;
> +	int rx_index;
> +	int c_index;
> +	int phyaddr;
> +	u32 interface;
> +	u32 speed;
> +	struct phy_device *phydev;
> +	struct mii_dev *bus;
> +};
> +
> +static void bcmgenet_umac_reset(struct bcmgenet_eth_priv *priv)
> +{
> +	u32 reg;
> +
> +	reg = readl(priv->mac_reg + SYS_RBUF_FLUSH_CTRL);
> +	reg |= BIT(1);
> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> +	udelay(10);
> +
> +	reg &= ~BIT(1);
> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> +	udelay(10);
> +
> +	writel(0, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> +	udelay(10);
> +
> +	writel(0, priv->mac_reg + UMAC_CMD);
> +
> +	writel(CMD_SW_RESET | CMD_LCL_LOOP_EN, priv->mac_reg + UMAC_CMD);
> +	udelay(2);
> +	writel(0, priv->mac_reg + UMAC_CMD);
> +
> +	/* clear tx/rx counter */
> +	writel(MIB_RESET_RX | MIB_RESET_TX | MIB_RESET_RUNT,
> +	       priv->mac_reg + UMAC_MIB_CTRL);
> +	writel(0, priv->mac_reg + UMAC_MIB_CTRL);
> +
> +	writel(ENET_MAX_MTU_SIZE, priv->mac_reg + UMAC_MAX_FRAME_LEN);
> +
> +	/* init rx registers, enable ip header optimization */
> +	reg = readl(priv->mac_reg + RBUF_CTRL);
> +	reg |= RBUF_ALIGN_2B;
> +	writel(reg, (priv->mac_reg + RBUF_CTRL));
> +
> +	writel(1, (priv->mac_reg + RBUF_TBUF_SIZE_CTRL));
> +}
> +
> +static int bcmgenet_gmac_write_hwaddr(struct udevice *dev)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> +	uchar *addr = pdata->enetaddr;
> +	u32 reg;
> +
> +	reg = addr[0] << 24 | addr[1] << 16 | addr[2] << 8 | addr[3];
> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC0);
> +
> +	reg = addr[4] << 8 | addr[5];
> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC1);
> +
> +	return 0;
> +}
> +
> +static void bcmgenet_disable_dma(struct bcmgenet_eth_priv *priv)
> +{
> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL, DMA_EN);
> +	clrbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, DMA_EN);
> +
> +	writel(1, priv->mac_reg + UMAC_TX_FLUSH);
> +	udelay(10);
> +	writel(0, priv->mac_reg + UMAC_TX_FLUSH);
> +}
> +
> +static void bcmgenet_enable_dma(struct bcmgenet_eth_priv *priv)
> +{
> +	u32 dma_ctrl = (1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT)) | DMA_EN;
> +
> +	writel(dma_ctrl, priv->mac_reg + TDMA_REG_BASE + DMA_CTRL);
> +
> +	setbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, dma_ctrl);
> +}
> +
> +static int bcmgenet_gmac_eth_send(struct udevice *dev, void *packet, int length)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	void *desc_base = priv->tx_desc_base + priv->tx_index * DMA_DESC_SIZE;
> +	u32 len_stat = length << DMA_BUFLENGTH_SHIFT;
> +	ulong packet_aligned = rounddown((ulong)packet, ARCH_DMA_MINALIGN);
> +	u32 prod_index, cons;
> +	u32 tries = 100;
> +
> +	prod_index = readl(priv->mac_reg + TDMA_PROD_INDEX);
> +
> +	/* There is actually no reason for the rounding here, but the ARMv7
> +	 * implementation of flush_dcache_range() checks for aligned
> +	 * boundaries of the flushed range.
> +	 * Adjust them here to pass that check and avoid misleading messages.
> +	 */
> +	flush_dcache_range(packet_aligned,
> +			   packet_aligned + roundup(length, ARCH_DMA_MINALIGN));
> +
> +	len_stat |= 0x3F << DMA_TX_QTAG_SHIFT;
> +	len_stat |= DMA_TX_APPEND_CRC | DMA_SOP | DMA_EOP;
> +
> +	/* Set-up packet for transmission */
> +	writel(lower_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_LO));
> +	writel(upper_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_HI));
> +	writel(len_stat, (desc_base + DMA_DESC_LENGTH_STATUS));
> +
> +	/* Increment index and start transmission */
> +	if (++priv->tx_index >= TX_DESCS)
> +		priv->tx_index = 0;
> +
> +	prod_index++;
> +
> +	/* Start Transmisson */
> +	writel(prod_index, priv->mac_reg + TDMA_PROD_INDEX);
> +
> +	do {
> +		cons = readl(priv->mac_reg + TDMA_CONS_INDEX);
> +	} while ((cons & 0xffff) < prod_index && --tries);
> +	if (!tries)
> +		return -ETIMEDOUT;
> +
> +	return 0;
> +}
> +
> +/* Check whether all cache lines affected by an invalidate are within
> + * the buffer, to make sure we don't accidentally lose unrelated dirty
> + * data stored nearby.
> + * Alignment of the buffer start address will be checked in the implementation
> + * of invalidate_dcache_range().
> + */
> +static void invalidate_dcache_check(unsigned long addr, size_t size,
> +				    size_t buffer_size)
> +{
> +	size_t inval_size = roundup(size, ARCH_DMA_MINALIGN);
> +
> +	if (unlikely(inval_size > buffer_size))
> +		printf("WARNING: Cache invalidate area exceeds buffer size\n");
> +
> +	invalidate_dcache_range(addr, addr + inval_size);
> +}
> +
> +static int bcmgenet_gmac_eth_recv(struct udevice *dev,
> +				  int flags, uchar **packetp)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	void *desc_base = priv->rx_desc_base + priv->rx_index * DMA_DESC_SIZE;
> +	u32 prod_index = readl(priv->mac_reg + RDMA_PROD_INDEX);
> +	u32 length, addr;
> +
> +	if (prod_index == priv->c_index)
> +		return -EAGAIN;
> +
> +	length = readl(desc_base + DMA_DESC_LENGTH_STATUS);
> +	length = (length >> DMA_BUFLENGTH_SHIFT) & DMA_BUFLENGTH_MASK;
> +	addr = readl(desc_base + DMA_DESC_ADDRESS_LO);
> +
> +	invalidate_dcache_check(addr, length, RX_BUF_LENGTH);
> +
> +	/* To cater for the IP header alignment the hardware does.
> +	 * This would actually not be needed if we don't program
> +	 * RBUF_ALIGN_2B
> +	 */
> +	*packetp = (uchar *)(ulong)addr + RX_BUF_OFFSET;
> +
> +	return length - RX_BUF_OFFSET;
> +}
> +
> +static int bcmgenet_gmac_free_pkt(struct udevice *dev, uchar *packet,
> +				  int length)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +
> +	/* Tell the MAC we have consumed that last receive buffer. */
> +	priv->c_index = (priv->c_index + 1) & 0xFFFF;
> +	writel(priv->c_index, priv->mac_reg + RDMA_CONS_INDEX);
> +
> +	/* Forward our descriptor pointer, wrapping around if needed. */
> +	if (++priv->rx_index >= RX_DESCS)
> +		priv->rx_index = 0;
> +
> +	return 0;
> +}
> +
> +static void rx_descs_init(struct bcmgenet_eth_priv *priv)
> +{
> +	char *rxbuffs = &priv->rxbuffer[0];
> +	u32 len_stat, i;
> +	void *desc_base = priv->rx_desc_base;
> +
> +	priv->c_index = 0;
> +
> +	len_stat = (RX_BUF_LENGTH << DMA_BUFLENGTH_SHIFT) | DMA_OWN;
> +
> +	for (i = 0; i < RX_DESCS; i++) {
> +		writel(lower_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_LO);
> +		writel(upper_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_HI);
> +		writel(len_stat,
> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_LENGTH_STATUS);
> +	}
> +}
> +
> +static void rx_ring_init(struct bcmgenet_eth_priv *priv)
> +{
> +	writel(DMA_MAX_BURST_LENGTH,
> +	       priv->mac_reg + RDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> +
> +	writel(0x0, priv->mac_reg + RDMA_RING_REG_BASE + DMA_START_ADDR);
> +	writel(0x0, priv->mac_reg + RDMA_READ_PTR);
> +	writel(0x0, priv->mac_reg + RDMA_WRITE_PTR);
> +	writel(RX_DESCS * DMA_DESC_SIZE / 4 - 1,
> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_END_ADDR);
> +
> +	writel(0x0, priv->mac_reg + RDMA_PROD_INDEX);
> +	writel(0x0, priv->mac_reg + RDMA_CONS_INDEX);
> +	writel((RX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> +	writel(DMA_FC_THRESH_VALUE, priv->mac_reg + RDMA_XON_XOFF_THRESH);
> +	writel(1 << DEFAULT_Q, priv->mac_reg + RDMA_REG_BASE + DMA_RING_CFG);
> +}
> +
> +static void tx_ring_init(struct bcmgenet_eth_priv *priv)
> +{
> +	writel(DMA_MAX_BURST_LENGTH,
> +	       priv->mac_reg + TDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> +
> +	writel(0x0, priv->mac_reg + TDMA_RING_REG_BASE + DMA_START_ADDR);
> +	writel(0x0, priv->mac_reg + TDMA_READ_PTR);
> +	writel(0x0, priv->mac_reg + TDMA_WRITE_PTR);
> +	writel(TX_DESCS * DMA_DESC_SIZE / 4 - 1,
> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_END_ADDR);
> +	writel(0x0, priv->mac_reg + TDMA_PROD_INDEX);
> +	writel(0x0, priv->mac_reg + TDMA_CONS_INDEX);
> +	writel(0x1, priv->mac_reg + TDMA_RING_REG_BASE + DMA_MBUF_DONE_THRESH);
> +	writel(0x0, priv->mac_reg + TDMA_FLOW_PERIOD);
> +	writel((TX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> +
> +	writel(1 << DEFAULT_Q, priv->mac_reg + TDMA_REG_BASE + DMA_RING_CFG);
> +}
> +
> +static int bcmgenet_adjust_link(struct bcmgenet_eth_priv *priv)
> +{
> +	struct phy_device *phy_dev = priv->phydev;
> +	u32 speed;
> +
> +	switch (phy_dev->speed) {
> +	case SPEED_1000:
> +		speed = UMAC_SPEED_1000;
> +		break;
> +	case SPEED_100:
> +		speed = UMAC_SPEED_100;
> +		break;
> +	case SPEED_10:
> +		speed = UMAC_SPEED_10;
> +		break;
> +	default:
> +		printf("bcmgenet: Unsupported PHY speed: %d\n", phy_dev->speed);
> +		return -EINVAL;
> +	}
> +
> +	clrsetbits_32(priv->mac_reg + EXT_RGMII_OOB_CTRL, OOB_DISABLE,
> +			RGMII_LINK | RGMII_MODE_EN | ID_MODE_DIS);
> +
> +	writel(speed << CMD_SPEED_SHIFT, (priv->mac_reg + UMAC_CMD));
> +
> +	return 0;
> +}
> +
> +static int bcmgenet_gmac_eth_start(struct udevice *dev)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	int ret;
> +
> +	priv->tx_desc_base = priv->mac_reg + GENET_TX_OFF;
> +	priv->rx_desc_base = priv->mac_reg + GENET_RX_OFF;
> +	priv->tx_index = 0x0;
> +	priv->rx_index = 0x0;
> +
> +	bcmgenet_umac_reset(priv);
> +
> +	bcmgenet_gmac_write_hwaddr(dev);
> +
> +	/* Disable RX/TX DMA and flush TX queues */
> +	bcmgenet_disable_dma(priv);
> +
> +	rx_ring_init(priv);
> +	rx_descs_init(priv);
> +
> +	tx_ring_init(priv);
> +
> +	/* Enable RX/TX DMA */
> +	bcmgenet_enable_dma(priv);
> +
> +	/* read PHY properties over the wire from generic PHY set-up */
> +	ret = phy_startup(priv->phydev);
> +	if (ret) {
> +		printf("bcmgenet: PHY startup failed: %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* Update MAC registers based on PHY property */
> +	ret = bcmgenet_adjust_link(priv);
> +	if (ret) {
> +		printf("bcmgenet: adjust PHY link failed: %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* Enable Rx/Tx */
> +	setbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> +
> +	return 0;
> +}
> +
> +static int bcmgenet_phy_init(struct bcmgenet_eth_priv *priv, void *dev)
> +{
> +	struct phy_device *phydev;
> +	int ret;
> +
> +	phydev = phy_connect(priv->bus, priv->phyaddr, dev, priv->interface);
> +	if (!phydev)
> +		return -ENODEV;
> +
> +	phydev->supported &= PHY_GBIT_FEATURES;
> +	if (priv->speed) {
> +		ret = phy_set_supported(priv->phydev, priv->speed);
> +		if (ret)
> +			return ret;
> +	}
> +	phydev->advertising = phydev->supported;
> +
> +	phy_connect_dev(phydev, dev);
> +
> +	priv->phydev = phydev;
> +	phy_config(priv->phydev);
> +
> +	return 0;
> +}
> +
> +static void bcmgenet_mdio_start(struct bcmgenet_eth_priv *priv)
> +{
> +	setbits_32(priv->mac_reg + MDIO_CMD, MDIO_START_BUSY);
> +}
> +
> +static int bcmgenet_mdio_write(struct mii_dev *bus, int addr, int devad,
> +			       int reg, u16 value)
> +{
> +	struct udevice *dev = bus->priv;
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	u32 val;
> +
> +	/* Prepare the read operation */
> +	val = MDIO_WR | (addr << MDIO_PMD_SHIFT) |
> +		(reg << MDIO_REG_SHIFT) | (0xffff & value);
> +	writel_relaxed(val,  priv->mac_reg + MDIO_CMD);
> +
> +	/* Start MDIO transaction */
> +	bcmgenet_mdio_start(priv);
> +
> +	return wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> +			       MDIO_START_BUSY, false, 20, true);
> +}
> +
> +static int bcmgenet_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
> +{
> +	struct udevice *dev = bus->priv;
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	u32 val;
> +	int ret;
> +
> +	/* Prepare the read operation */
> +	val = MDIO_RD | (addr << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
> +	writel_relaxed(val, priv->mac_reg + MDIO_CMD);
> +
> +	/* Start MDIO transaction */
> +	bcmgenet_mdio_start(priv);
> +
> +	ret = wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> +			      MDIO_START_BUSY, false, 20, true);
> +	if (ret)
> +		return ret;
> +
> +	val = readl_relaxed(priv->mac_reg + MDIO_CMD);
> +
> +	return val & 0xffff;
> +}
> +
> +static int bcmgenet_mdio_init(const char *name, struct udevice *priv)
> +{
> +	struct mii_dev *bus = mdio_alloc();
> +
> +	if (!bus) {
> +		debug("Failed to allocate MDIO bus\n");
> +		return -ENOMEM;
> +	}
> +
> +	bus->read = bcmgenet_mdio_read;
> +	bus->write = bcmgenet_mdio_write;
> +	snprintf(bus->name, sizeof(bus->name), name);
> +	bus->priv = (void *)priv;
> +
> +	return mdio_register(bus);
> +}
> +
> +/* We only support RGMII (as used on the RPi4). */
> +static int bcmgenet_interface_set(struct bcmgenet_eth_priv *priv)
> +{
> +	phy_interface_t phy_mode = priv->interface;
> +
> +	switch (phy_mode) {
> +	case PHY_INTERFACE_MODE_RGMII:
> +	case PHY_INTERFACE_MODE_RGMII_RXID:
> +		writel(PORT_MODE_EXT_GPHY, priv->mac_reg + SYS_PORT_CTRL);
> +		break;
> +	default:
> +		printf("unknown phy mode: %d\n", priv->interface);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int bcmgenet_eth_probe(struct udevice *dev)
> +{
> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	ofnode mdio_node;
> +	const char *name;
> +	u32 reg;
> +	int ret;
> +	u8 major;
> +
> +	priv->mac_reg = map_physmem(pdata->iobase, SZ_64K, MAP_NOCACHE);
> +	priv->interface = pdata->phy_interface;
> +	priv->speed = pdata->max_speed;
> +
> +	/* Read GENET HW version */
> +	reg = readl_relaxed(priv->mac_reg + SYS_REV_CTRL);
> +	major = (reg >> 24) & 0x0f;
> +	if (major != 6) {
> +		if (major == 5)
> +			major = 4;
> +		else if (major == 0)
> +			major = 1;
> +
> +		printf("Unsupported GENETv%d.%d\n", major, (reg >> 16) & 0x0f);
> +		return -ENODEV;
> +	}
> +
> +	ret = bcmgenet_interface_set(priv);
> +	if (ret)
> +		return ret;
> +
> +	mdio_node = dev_read_first_subnode(dev);
> +	name = ofnode_get_name(mdio_node);
> +
> +	ret = bcmgenet_mdio_init(name, dev);
> +	if (ret)
> +		return ret;
> +
> +	priv->bus = miiphy_get_dev_by_name(name);
> +
> +	return bcmgenet_phy_init(priv, dev);
> +}
> +
> +static void bcmgenet_gmac_eth_stop(struct udevice *dev)
> +{
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +
> +	clrbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL,
> +		     1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT) | DMA_EN);
> +}
> +
> +static const struct eth_ops bcmgenet_gmac_eth_ops = {
> +	.start                  = bcmgenet_gmac_eth_start,
> +	.write_hwaddr           = bcmgenet_gmac_write_hwaddr,
> +	.send                   = bcmgenet_gmac_eth_send,
> +	.recv                   = bcmgenet_gmac_eth_recv,
> +	.free_pkt               = bcmgenet_gmac_free_pkt,
> +	.stop                   = bcmgenet_gmac_eth_stop,
> +};
> +
> +static int bcmgenet_eth_ofdata_to_platdata(struct udevice *dev)
> +{
> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> +	struct ofnode_phandle_args phy_node;
> +	const char *phy_mode;
> +	int ret;
> +
> +	pdata->iobase = dev_read_addr(dev);

I suggest to change the type of pdata->iobase to void __iomem * and use
dev_remap_addr(). This saves you the manual map_physmem() in
bcmgenet_eth_probe(). Also dev_remap_addr() uses the correct register
size from DT instead of the hard-coded SZ_64K.

> +
> +	/* Get phy mode from DT */
> +	pdata->phy_interface = -1;
> +	phy_mode = dev_read_string(dev, "phy-mode");
> +	if (phy_mode)
> +		pdata->phy_interface = phy_get_interface_by_name(phy_mode);
> +	if (pdata->phy_interface == -1) {
> +		debug("%s: Invalid PHY interface '%s'\n", __func__, phy_mode);
> +		return -EINVAL;
> +	}
> +
> +	ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
> +					 &phy_node);
> +	if (!ret) {
> +		ofnode_read_s32(phy_node.node, "reg", &priv->phyaddr);
> +		ofnode_read_s32(phy_node.node, "max-speed", &pdata->max_speed);
> +	}
> +
> +	return 0;
> +}
> +
> +/* The BCM2711 implementation has a limited burst length compared to a generic
> + * GENETv5 version, but we go with that shorter value (8) in both cases, for
> + * the sake of simplicity.
> + */
> +static const struct udevice_id bcmgenet_eth_ids[] = {
> +	{.compatible = "brcm,genet-v5"},
> +	{.compatible = "brcm,bcm2711-genet-v5"},
> +	{}
> +};
> +
> +U_BOOT_DRIVER(eth_bcmgenet) = {
> +	.name   = "eth_bcmgenet",
> +	.id     = UCLASS_ETH,
> +	.of_match = bcmgenet_eth_ids,
> +	.ofdata_to_platdata = bcmgenet_eth_ofdata_to_platdata,
> +	.probe  = bcmgenet_eth_probe,
> +	.ops    = &bcmgenet_gmac_eth_ops,
> +	.priv_auto_alloc_size = sizeof(struct bcmgenet_eth_priv),
> +	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
> +	.flags = DM_FLAG_ALLOC_PRIV_DMA,
> +};
>
Andre Przywara Jan. 22, 2020, 3:36 p.m. | #3
On Wed, 22 Jan 2020 16:02:22 +0100
Daniel Schwierzeck <daniel.schwierzeck at gmail.com> wrote:

Hi Daniel,

> Am 17.01.20 um 02:20 schrieb Andre Przywara:
> > From: Amit Singh Tomar <amittomer25 at gmail.com>
> > 
> > The Broadcom GENET Ethernet MACs are used in several MIPS based SoCs
> > and in the Broadcom 2711/2838 SoC used on the Raspberry Pi 4.
> > There is no publicly available documentation, so this driver is based
> > on the Linux driver. Compared to that the queue management is
> > drastically simplified, also we only support version 5 of the IP and
> > RGMII connections between MAC and PHY, as used on the RPi4.
> > 
> > Signed-off-by: Amit Singh Tomar <amittomer25 at gmail.com>
> > Reviewed-by: Andre Przywara <andre.przywara at arm.com>
> > [Andre: heavy cleanup and a few fixes]
> > Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> > ---
> >  drivers/net/Kconfig    |   7 +
> >  drivers/net/Makefile   |   1 +
> >  drivers/net/bcmgenet.c | 722 +++++++++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 730 insertions(+)
> >  create mode 100644 drivers/net/bcmgenet.c  
> 
> Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>

Many thanks!

> > 
> > diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
> > index 01d087f229..4d1013c984 100644
> > --- a/drivers/net/Kconfig
> > +++ b/drivers/net/Kconfig
> > @@ -136,6 +136,13 @@ config BCM6368_ETH
> >  	help
> >  	  This driver supports the BCM6368 Ethernet MAC.
> >  
> > +config BCMGENET
> > +	bool "BCMGENET V5 support"
> > +	depends on DM_ETH  
> 
> maybe this should be limited to the supported SoC's?
> 
> e.g.  depends on DM_ETH && ARCH_BCM283X

Technically this would not be correct: Nothing in the driver *code* depends on the Broadcom 2711 SoC. It uses generic accessors for the MMIO registers and the probe function is using generic DM routines. The rest is GENET driver code, which would even work on other architectures (hence the endianess changes).
It would be a different story if we would take any 2711 specific shortcuts in the code, say poking some special hardcoded register to configure some clocks or the like.

Or is there any actual problem that you are thinking about, that would require this to be restricted?

> 
> > +	select PHYLIB
> > +	help
> > +	  This driver supports the BCMGENET Ethernet MAC.
> > +
> >  config DWC_ETH_QOS
> >  	bool "Synopsys DWC Ethernet QOS device support"
> >  	depends on DM_ETH
> > diff --git a/drivers/net/Makefile b/drivers/net/Makefile
> > index 30991834ec..6e0a68834d 100644
> > --- a/drivers/net/Makefile
> > +++ b/drivers/net/Makefile
> > @@ -8,6 +8,7 @@ obj-$(CONFIG_AG7XXX) += ag7xxx.o
> >  obj-$(CONFIG_ARMADA100_FEC) += armada100_fec.o
> >  obj-$(CONFIG_BCM6348_ETH) += bcm6348-eth.o
> >  obj-$(CONFIG_BCM6368_ETH) += bcm6368-eth.o
> > +obj-$(CONFIG_BCMGENET) += bcmgenet.o
> >  obj-$(CONFIG_DRIVER_AT91EMAC) += at91_emac.o
> >  obj-$(CONFIG_DRIVER_AX88180) += ax88180.o
> >  obj-$(CONFIG_BCM_SF2_ETH) += bcm-sf2-eth.o
> > diff --git a/drivers/net/bcmgenet.c b/drivers/net/bcmgenet.c
> > new file mode 100644
> > index 0000000000..4f8f190071
> > --- /dev/null
> > +++ b/drivers/net/bcmgenet.c
> > @@ -0,0 +1,722 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright (C) 2019 Amit Singh Tomar <amittomer25 at gmail.com>
> > + *
> > + * Driver for Broadcom GENETv5 Ethernet controller (as found on the RPi4)
> > + * This driver is based on the Linux driver:
> > + *      drivers/net/ethernet/broadcom/genet/bcmgenet.c
> > + *      which is: Copyright (c) 2014-2017 Broadcom
> > + *
> > + * The hardware supports multiple queues (16 priority queues and one
> > + * default queue), both for RX and TX. There are 256 DMA descriptors (both
> > + * for TX and RX), and they live in MMIO registers. The hardware allows
> > + * assigning descriptor ranges to queues, but we choose the most simple setup:
> > + * All 256 descriptors are assigned to the default queue (#16).
> > + * Also the Linux driver supports multiple generations of the MAC, whereas
> > + * we only support v5, as used in the Raspberry Pi 4.
> > + */
> > +
> > +#include <asm/io.h>
> > +#include <clk.h>
> > +#include <cpu_func.h>
> > +#include <dm.h>
> > +#include <fdt_support.h>
> > +#include <linux/err.h>
> > +#include <malloc.h>
> > +#include <miiphy.h>
> > +#include <net.h>
> > +#include <dm/of_access.h>
> > +#include <dm/ofnode.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/sizes.h>
> > +#include <asm/dma-mapping.h>
> > +#include <wait_bit.h>
> > +
> > +/* Register definitions derived from Linux source */
> > +#define SYS_REV_CTRL			0x00
> > +
> > +#define SYS_PORT_CTRL			0x04
> > +#define PORT_MODE_EXT_GPHY		3
> > +
> > +#define GENET_SYS_OFF			0x0000
> > +#define SYS_RBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x08)
> > +#define SYS_TBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x0c)
> > +
> > +#define GENET_EXT_OFF			0x0080
> > +#define EXT_RGMII_OOB_CTRL		(GENET_EXT_OFF + 0x0c)
> > +#define RGMII_LINK			BIT(4)
> > +#define OOB_DISABLE			BIT(5)
> > +#define RGMII_MODE_EN			BIT(6)
> > +#define ID_MODE_DIS			BIT(16)
> > +
> > +#define GENET_RBUF_OFF			0x0300
> > +#define RBUF_TBUF_SIZE_CTRL		(GENET_RBUF_OFF + 0xb4)
> > +#define RBUF_CTRL			(GENET_RBUF_OFF + 0x00)
> > +#define RBUF_ALIGN_2B			BIT(1)
> > +
> > +#define GENET_UMAC_OFF			0x0800
> > +#define UMAC_MIB_CTRL			(GENET_UMAC_OFF + 0x580)
> > +#define UMAC_MAX_FRAME_LEN		(GENET_UMAC_OFF + 0x014)
> > +#define UMAC_MAC0			(GENET_UMAC_OFF + 0x00c)
> > +#define UMAC_MAC1			(GENET_UMAC_OFF + 0x010)
> > +#define UMAC_CMD			(GENET_UMAC_OFF + 0x008)
> > +#define MDIO_CMD			(GENET_UMAC_OFF + 0x614)
> > +#define UMAC_TX_FLUSH			(GENET_UMAC_OFF + 0x334)
> > +#define MDIO_START_BUSY			BIT(29)
> > +#define MDIO_READ_FAIL			BIT(28)
> > +#define MDIO_RD				(2 << 26)
> > +#define MDIO_WR				BIT(26)
> > +#define MDIO_PMD_SHIFT			21
> > +#define MDIO_PMD_MASK			0x1f
> > +#define MDIO_REG_SHIFT			16
> > +#define MDIO_REG_MASK			0x1f
> > +
> > +#define CMD_TX_EN			BIT(0)
> > +#define CMD_RX_EN			BIT(1)
> > +#define UMAC_SPEED_10			0
> > +#define UMAC_SPEED_100			1
> > +#define UMAC_SPEED_1000			2
> > +#define UMAC_SPEED_2500			3
> > +#define CMD_SPEED_SHIFT			2
> > +#define CMD_SPEED_MASK			3
> > +#define CMD_SW_RESET			BIT(13)
> > +#define CMD_LCL_LOOP_EN			BIT(15)
> > +#define CMD_TX_EN			BIT(0)
> > +#define CMD_RX_EN			BIT(1)
> > +
> > +#define MIB_RESET_RX			BIT(0)
> > +#define MIB_RESET_RUNT			BIT(1)
> > +#define MIB_RESET_TX			BIT(2)
> > +
> > +/* total number of Buffer Descriptors, same for Rx/Tx */
> > +#define TOTAL_DESCS			256
> > +#define RX_DESCS			TOTAL_DESCS
> > +#define TX_DESCS			TOTAL_DESCS
> > +
> > +#define DEFAULT_Q			0x10
> > +
> > +/* Body(1500) + EH_SIZE(14) + VLANTAG(4) + BRCMTAG(6) + FCS(4) = 1528.
> > + * 1536 is multiple of 256 bytes
> > + */
> > +#define ENET_BRCM_TAG_LEN		6
> > +#define ENET_PAD			8
> > +#define ENET_MAX_MTU_SIZE		(ETH_DATA_LEN + ETH_HLEN +	 \
> > +					 VLAN_HLEN + ENET_BRCM_TAG_LEN + \
> > +					 ETH_FCS_LEN + ENET_PAD)
> > +
> > +/* Tx/Rx Dma Descriptor common bits */
> > +#define DMA_EN				BIT(0)
> > +#define DMA_RING_BUF_EN_SHIFT		0x01
> > +#define DMA_RING_BUF_EN_MASK		0xffff
> > +#define DMA_BUFLENGTH_MASK		0x0fff
> > +#define DMA_BUFLENGTH_SHIFT		16
> > +#define DMA_RING_SIZE_SHIFT		16
> > +#define DMA_OWN				0x8000
> > +#define DMA_EOP				0x4000
> > +#define DMA_SOP				0x2000
> > +#define DMA_WRAP			0x1000
> > +#define DMA_MAX_BURST_LENGTH		0x8
> > +/* Tx specific DMA descriptor bits */
> > +#define DMA_TX_UNDERRUN			0x0200
> > +#define DMA_TX_APPEND_CRC		0x0040
> > +#define DMA_TX_OW_CRC			0x0020
> > +#define DMA_TX_DO_CSUM			0x0010
> > +#define DMA_TX_QTAG_SHIFT		7
> > +
> > +/* DMA rings size */
> > +#define DMA_RING_SIZE			0x40
> > +#define DMA_RINGS_SIZE			(DMA_RING_SIZE * (DEFAULT_Q + 1))
> > +
> > +/* DMA descriptor */
> > +#define DMA_DESC_LENGTH_STATUS		0x00
> > +#define DMA_DESC_ADDRESS_LO		0x04
> > +#define DMA_DESC_ADDRESS_HI		0x08
> > +#define DMA_DESC_SIZE			12
> > +
> > +#define GENET_RX_OFF			0x2000
> > +#define GENET_RDMA_REG_OFF					\
> > +	(GENET_RX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> > +#define GENET_TX_OFF			0x4000
> > +#define GENET_TDMA_REG_OFF					\
> > +	(GENET_TX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> > +
> > +#define DMA_FC_THRESH_HI		(RX_DESCS >> 4)
> > +#define DMA_FC_THRESH_LO		5
> > +#define DMA_FC_THRESH_VALUE		((DMA_FC_THRESH_LO << 16) |	\
> > +					  DMA_FC_THRESH_HI)
> > +
> > +#define DMA_XOFF_THRESHOLD_SHIFT	16
> > +
> > +#define TDMA_RING_REG_BASE					\
> > +	(GENET_TDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> > +#define TDMA_READ_PTR			(TDMA_RING_REG_BASE + 0x00)
> > +#define TDMA_CONS_INDEX			(TDMA_RING_REG_BASE + 0x08)
> > +#define TDMA_PROD_INDEX			(TDMA_RING_REG_BASE + 0x0c)
> > +#define DMA_RING_BUF_SIZE		0x10
> > +#define DMA_START_ADDR			0x14
> > +#define DMA_END_ADDR			0x1c
> > +#define DMA_MBUF_DONE_THRESH		0x24
> > +#define TDMA_FLOW_PERIOD		(TDMA_RING_REG_BASE + 0x28)
> > +#define TDMA_WRITE_PTR			(TDMA_RING_REG_BASE + 0x2c)
> > +
> > +#define RDMA_RING_REG_BASE					\
> > +	(GENET_RDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> > +#define RDMA_WRITE_PTR			(RDMA_RING_REG_BASE + 0x00)
> > +#define RDMA_PROD_INDEX			(RDMA_RING_REG_BASE + 0x08)
> > +#define RDMA_CONS_INDEX			(RDMA_RING_REG_BASE + 0x0c)
> > +#define RDMA_XON_XOFF_THRESH		(RDMA_RING_REG_BASE + 0x28)
> > +#define RDMA_READ_PTR			(RDMA_RING_REG_BASE + 0x2c)
> > +
> > +#define TDMA_REG_BASE			(GENET_TDMA_REG_OFF + DMA_RINGS_SIZE)
> > +#define RDMA_REG_BASE			(GENET_RDMA_REG_OFF + DMA_RINGS_SIZE)
> > +#define DMA_RING_CFG			0x00
> > +#define DMA_CTRL			0x04
> > +#define DMA_SCB_BURST_SIZE		0x0c
> > +
> > +#define RX_BUF_LENGTH			2048
> > +#define RX_TOTAL_BUFSIZE		(RX_BUF_LENGTH * RX_DESCS)
> > +#define RX_BUF_OFFSET			2
> > +
> > +struct bcmgenet_eth_priv {
> > +	char rxbuffer[RX_TOTAL_BUFSIZE] __aligned(ARCH_DMA_MINALIGN);
> > +	void *mac_reg;
> > +	void *tx_desc_base;
> > +	void *rx_desc_base;
> > +	int tx_index;
> > +	int rx_index;
> > +	int c_index;
> > +	int phyaddr;
> > +	u32 interface;
> > +	u32 speed;
> > +	struct phy_device *phydev;
> > +	struct mii_dev *bus;
> > +};
> > +
> > +static void bcmgenet_umac_reset(struct bcmgenet_eth_priv *priv)
> > +{
> > +	u32 reg;
> > +
> > +	reg = readl(priv->mac_reg + SYS_RBUF_FLUSH_CTRL);
> > +	reg |= BIT(1);
> > +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> > +	udelay(10);
> > +
> > +	reg &= ~BIT(1);
> > +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> > +	udelay(10);
> > +
> > +	writel(0, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> > +	udelay(10);
> > +
> > +	writel(0, priv->mac_reg + UMAC_CMD);
> > +
> > +	writel(CMD_SW_RESET | CMD_LCL_LOOP_EN, priv->mac_reg + UMAC_CMD);
> > +	udelay(2);
> > +	writel(0, priv->mac_reg + UMAC_CMD);
> > +
> > +	/* clear tx/rx counter */
> > +	writel(MIB_RESET_RX | MIB_RESET_TX | MIB_RESET_RUNT,
> > +	       priv->mac_reg + UMAC_MIB_CTRL);
> > +	writel(0, priv->mac_reg + UMAC_MIB_CTRL);
> > +
> > +	writel(ENET_MAX_MTU_SIZE, priv->mac_reg + UMAC_MAX_FRAME_LEN);
> > +
> > +	/* init rx registers, enable ip header optimization */
> > +	reg = readl(priv->mac_reg + RBUF_CTRL);
> > +	reg |= RBUF_ALIGN_2B;
> > +	writel(reg, (priv->mac_reg + RBUF_CTRL));
> > +
> > +	writel(1, (priv->mac_reg + RBUF_TBUF_SIZE_CTRL));
> > +}
> > +
> > +static int bcmgenet_gmac_write_hwaddr(struct udevice *dev)
> > +{
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	struct eth_pdata *pdata = dev_get_platdata(dev);
> > +	uchar *addr = pdata->enetaddr;
> > +	u32 reg;
> > +
> > +	reg = addr[0] << 24 | addr[1] << 16 | addr[2] << 8 | addr[3];
> > +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC0);
> > +
> > +	reg = addr[4] << 8 | addr[5];
> > +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC1);
> > +
> > +	return 0;
> > +}
> > +
> > +static void bcmgenet_disable_dma(struct bcmgenet_eth_priv *priv)
> > +{
> > +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL, DMA_EN);
> > +	clrbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, DMA_EN);
> > +
> > +	writel(1, priv->mac_reg + UMAC_TX_FLUSH);
> > +	udelay(10);
> > +	writel(0, priv->mac_reg + UMAC_TX_FLUSH);
> > +}
> > +
> > +static void bcmgenet_enable_dma(struct bcmgenet_eth_priv *priv)
> > +{
> > +	u32 dma_ctrl = (1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT)) | DMA_EN;
> > +
> > +	writel(dma_ctrl, priv->mac_reg + TDMA_REG_BASE + DMA_CTRL);
> > +
> > +	setbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, dma_ctrl);
> > +}
> > +
> > +static int bcmgenet_gmac_eth_send(struct udevice *dev, void *packet, int length)
> > +{
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	void *desc_base = priv->tx_desc_base + priv->tx_index * DMA_DESC_SIZE;
> > +	u32 len_stat = length << DMA_BUFLENGTH_SHIFT;
> > +	ulong packet_aligned = rounddown((ulong)packet, ARCH_DMA_MINALIGN);
> > +	u32 prod_index, cons;
> > +	u32 tries = 100;
> > +
> > +	prod_index = readl(priv->mac_reg + TDMA_PROD_INDEX);
> > +
> > +	/* There is actually no reason for the rounding here, but the ARMv7
> > +	 * implementation of flush_dcache_range() checks for aligned
> > +	 * boundaries of the flushed range.
> > +	 * Adjust them here to pass that check and avoid misleading messages.
> > +	 */
> > +	flush_dcache_range(packet_aligned,
> > +			   packet_aligned + roundup(length, ARCH_DMA_MINALIGN));
> > +
> > +	len_stat |= 0x3F << DMA_TX_QTAG_SHIFT;
> > +	len_stat |= DMA_TX_APPEND_CRC | DMA_SOP | DMA_EOP;
> > +
> > +	/* Set-up packet for transmission */
> > +	writel(lower_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_LO));
> > +	writel(upper_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_HI));
> > +	writel(len_stat, (desc_base + DMA_DESC_LENGTH_STATUS));
> > +
> > +	/* Increment index and start transmission */
> > +	if (++priv->tx_index >= TX_DESCS)
> > +		priv->tx_index = 0;
> > +
> > +	prod_index++;
> > +
> > +	/* Start Transmisson */
> > +	writel(prod_index, priv->mac_reg + TDMA_PROD_INDEX);
> > +
> > +	do {
> > +		cons = readl(priv->mac_reg + TDMA_CONS_INDEX);
> > +	} while ((cons & 0xffff) < prod_index && --tries);
> > +	if (!tries)
> > +		return -ETIMEDOUT;
> > +
> > +	return 0;
> > +}
> > +
> > +/* Check whether all cache lines affected by an invalidate are within
> > + * the buffer, to make sure we don't accidentally lose unrelated dirty
> > + * data stored nearby.
> > + * Alignment of the buffer start address will be checked in the implementation
> > + * of invalidate_dcache_range().
> > + */
> > +static void invalidate_dcache_check(unsigned long addr, size_t size,
> > +				    size_t buffer_size)
> > +{
> > +	size_t inval_size = roundup(size, ARCH_DMA_MINALIGN);
> > +
> > +	if (unlikely(inval_size > buffer_size))
> > +		printf("WARNING: Cache invalidate area exceeds buffer size\n");
> > +
> > +	invalidate_dcache_range(addr, addr + inval_size);
> > +}
> > +
> > +static int bcmgenet_gmac_eth_recv(struct udevice *dev,
> > +				  int flags, uchar **packetp)
> > +{
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	void *desc_base = priv->rx_desc_base + priv->rx_index * DMA_DESC_SIZE;
> > +	u32 prod_index = readl(priv->mac_reg + RDMA_PROD_INDEX);
> > +	u32 length, addr;
> > +
> > +	if (prod_index == priv->c_index)
> > +		return -EAGAIN;
> > +
> > +	length = readl(desc_base + DMA_DESC_LENGTH_STATUS);
> > +	length = (length >> DMA_BUFLENGTH_SHIFT) & DMA_BUFLENGTH_MASK;
> > +	addr = readl(desc_base + DMA_DESC_ADDRESS_LO);
> > +
> > +	invalidate_dcache_check(addr, length, RX_BUF_LENGTH);
> > +
> > +	/* To cater for the IP header alignment the hardware does.
> > +	 * This would actually not be needed if we don't program
> > +	 * RBUF_ALIGN_2B
> > +	 */
> > +	*packetp = (uchar *)(ulong)addr + RX_BUF_OFFSET;
> > +
> > +	return length - RX_BUF_OFFSET;
> > +}
> > +
> > +static int bcmgenet_gmac_free_pkt(struct udevice *dev, uchar *packet,
> > +				  int length)
> > +{
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +
> > +	/* Tell the MAC we have consumed that last receive buffer. */
> > +	priv->c_index = (priv->c_index + 1) & 0xFFFF;
> > +	writel(priv->c_index, priv->mac_reg + RDMA_CONS_INDEX);
> > +
> > +	/* Forward our descriptor pointer, wrapping around if needed. */
> > +	if (++priv->rx_index >= RX_DESCS)
> > +		priv->rx_index = 0;
> > +
> > +	return 0;
> > +}
> > +
> > +static void rx_descs_init(struct bcmgenet_eth_priv *priv)
> > +{
> > +	char *rxbuffs = &priv->rxbuffer[0];
> > +	u32 len_stat, i;
> > +	void *desc_base = priv->rx_desc_base;
> > +
> > +	priv->c_index = 0;
> > +
> > +	len_stat = (RX_BUF_LENGTH << DMA_BUFLENGTH_SHIFT) | DMA_OWN;
> > +
> > +	for (i = 0; i < RX_DESCS; i++) {
> > +		writel(lower_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> > +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_LO);
> > +		writel(upper_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> > +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_HI);
> > +		writel(len_stat,
> > +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_LENGTH_STATUS);
> > +	}
> > +}
> > +
> > +static void rx_ring_init(struct bcmgenet_eth_priv *priv)
> > +{
> > +	writel(DMA_MAX_BURST_LENGTH,
> > +	       priv->mac_reg + RDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> > +
> > +	writel(0x0, priv->mac_reg + RDMA_RING_REG_BASE + DMA_START_ADDR);
> > +	writel(0x0, priv->mac_reg + RDMA_READ_PTR);
> > +	writel(0x0, priv->mac_reg + RDMA_WRITE_PTR);
> > +	writel(RX_DESCS * DMA_DESC_SIZE / 4 - 1,
> > +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_END_ADDR);
> > +
> > +	writel(0x0, priv->mac_reg + RDMA_PROD_INDEX);
> > +	writel(0x0, priv->mac_reg + RDMA_CONS_INDEX);
> > +	writel((RX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> > +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> > +	writel(DMA_FC_THRESH_VALUE, priv->mac_reg + RDMA_XON_XOFF_THRESH);
> > +	writel(1 << DEFAULT_Q, priv->mac_reg + RDMA_REG_BASE + DMA_RING_CFG);
> > +}
> > +
> > +static void tx_ring_init(struct bcmgenet_eth_priv *priv)
> > +{
> > +	writel(DMA_MAX_BURST_LENGTH,
> > +	       priv->mac_reg + TDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> > +
> > +	writel(0x0, priv->mac_reg + TDMA_RING_REG_BASE + DMA_START_ADDR);
> > +	writel(0x0, priv->mac_reg + TDMA_READ_PTR);
> > +	writel(0x0, priv->mac_reg + TDMA_WRITE_PTR);
> > +	writel(TX_DESCS * DMA_DESC_SIZE / 4 - 1,
> > +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_END_ADDR);
> > +	writel(0x0, priv->mac_reg + TDMA_PROD_INDEX);
> > +	writel(0x0, priv->mac_reg + TDMA_CONS_INDEX);
> > +	writel(0x1, priv->mac_reg + TDMA_RING_REG_BASE + DMA_MBUF_DONE_THRESH);
> > +	writel(0x0, priv->mac_reg + TDMA_FLOW_PERIOD);
> > +	writel((TX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> > +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> > +
> > +	writel(1 << DEFAULT_Q, priv->mac_reg + TDMA_REG_BASE + DMA_RING_CFG);
> > +}
> > +
> > +static int bcmgenet_adjust_link(struct bcmgenet_eth_priv *priv)
> > +{
> > +	struct phy_device *phy_dev = priv->phydev;
> > +	u32 speed;
> > +
> > +	switch (phy_dev->speed) {
> > +	case SPEED_1000:
> > +		speed = UMAC_SPEED_1000;
> > +		break;
> > +	case SPEED_100:
> > +		speed = UMAC_SPEED_100;
> > +		break;
> > +	case SPEED_10:
> > +		speed = UMAC_SPEED_10;
> > +		break;
> > +	default:
> > +		printf("bcmgenet: Unsupported PHY speed: %d\n", phy_dev->speed);
> > +		return -EINVAL;
> > +	}
> > +
> > +	clrsetbits_32(priv->mac_reg + EXT_RGMII_OOB_CTRL, OOB_DISABLE,
> > +			RGMII_LINK | RGMII_MODE_EN | ID_MODE_DIS);
> > +
> > +	writel(speed << CMD_SPEED_SHIFT, (priv->mac_reg + UMAC_CMD));
> > +
> > +	return 0;
> > +}
> > +
> > +static int bcmgenet_gmac_eth_start(struct udevice *dev)
> > +{
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	int ret;
> > +
> > +	priv->tx_desc_base = priv->mac_reg + GENET_TX_OFF;
> > +	priv->rx_desc_base = priv->mac_reg + GENET_RX_OFF;
> > +	priv->tx_index = 0x0;
> > +	priv->rx_index = 0x0;
> > +
> > +	bcmgenet_umac_reset(priv);
> > +
> > +	bcmgenet_gmac_write_hwaddr(dev);
> > +
> > +	/* Disable RX/TX DMA and flush TX queues */
> > +	bcmgenet_disable_dma(priv);
> > +
> > +	rx_ring_init(priv);
> > +	rx_descs_init(priv);
> > +
> > +	tx_ring_init(priv);
> > +
> > +	/* Enable RX/TX DMA */
> > +	bcmgenet_enable_dma(priv);
> > +
> > +	/* read PHY properties over the wire from generic PHY set-up */
> > +	ret = phy_startup(priv->phydev);
> > +	if (ret) {
> > +		printf("bcmgenet: PHY startup failed: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	/* Update MAC registers based on PHY property */
> > +	ret = bcmgenet_adjust_link(priv);
> > +	if (ret) {
> > +		printf("bcmgenet: adjust PHY link failed: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	/* Enable Rx/Tx */
> > +	setbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> > +
> > +	return 0;
> > +}
> > +
> > +static int bcmgenet_phy_init(struct bcmgenet_eth_priv *priv, void *dev)
> > +{
> > +	struct phy_device *phydev;
> > +	int ret;
> > +
> > +	phydev = phy_connect(priv->bus, priv->phyaddr, dev, priv->interface);
> > +	if (!phydev)
> > +		return -ENODEV;
> > +
> > +	phydev->supported &= PHY_GBIT_FEATURES;
> > +	if (priv->speed) {
> > +		ret = phy_set_supported(priv->phydev, priv->speed);
> > +		if (ret)
> > +			return ret;
> > +	}
> > +	phydev->advertising = phydev->supported;
> > +
> > +	phy_connect_dev(phydev, dev);
> > +
> > +	priv->phydev = phydev;
> > +	phy_config(priv->phydev);
> > +
> > +	return 0;
> > +}
> > +
> > +static void bcmgenet_mdio_start(struct bcmgenet_eth_priv *priv)
> > +{
> > +	setbits_32(priv->mac_reg + MDIO_CMD, MDIO_START_BUSY);
> > +}
> > +
> > +static int bcmgenet_mdio_write(struct mii_dev *bus, int addr, int devad,
> > +			       int reg, u16 value)
> > +{
> > +	struct udevice *dev = bus->priv;
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	u32 val;
> > +
> > +	/* Prepare the read operation */
> > +	val = MDIO_WR | (addr << MDIO_PMD_SHIFT) |
> > +		(reg << MDIO_REG_SHIFT) | (0xffff & value);
> > +	writel_relaxed(val,  priv->mac_reg + MDIO_CMD);
> > +
> > +	/* Start MDIO transaction */
> > +	bcmgenet_mdio_start(priv);
> > +
> > +	return wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> > +			       MDIO_START_BUSY, false, 20, true);
> > +}
> > +
> > +static int bcmgenet_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
> > +{
> > +	struct udevice *dev = bus->priv;
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	u32 val;
> > +	int ret;
> > +
> > +	/* Prepare the read operation */
> > +	val = MDIO_RD | (addr << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
> > +	writel_relaxed(val, priv->mac_reg + MDIO_CMD);
> > +
> > +	/* Start MDIO transaction */
> > +	bcmgenet_mdio_start(priv);
> > +
> > +	ret = wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> > +			      MDIO_START_BUSY, false, 20, true);
> > +	if (ret)
> > +		return ret;
> > +
> > +	val = readl_relaxed(priv->mac_reg + MDIO_CMD);
> > +
> > +	return val & 0xffff;
> > +}
> > +
> > +static int bcmgenet_mdio_init(const char *name, struct udevice *priv)
> > +{
> > +	struct mii_dev *bus = mdio_alloc();
> > +
> > +	if (!bus) {
> > +		debug("Failed to allocate MDIO bus\n");
> > +		return -ENOMEM;
> > +	}
> > +
> > +	bus->read = bcmgenet_mdio_read;
> > +	bus->write = bcmgenet_mdio_write;
> > +	snprintf(bus->name, sizeof(bus->name), name);
> > +	bus->priv = (void *)priv;
> > +
> > +	return mdio_register(bus);
> > +}
> > +
> > +/* We only support RGMII (as used on the RPi4). */
> > +static int bcmgenet_interface_set(struct bcmgenet_eth_priv *priv)
> > +{
> > +	phy_interface_t phy_mode = priv->interface;
> > +
> > +	switch (phy_mode) {
> > +	case PHY_INTERFACE_MODE_RGMII:
> > +	case PHY_INTERFACE_MODE_RGMII_RXID:
> > +		writel(PORT_MODE_EXT_GPHY, priv->mac_reg + SYS_PORT_CTRL);
> > +		break;
> > +	default:
> > +		printf("unknown phy mode: %d\n", priv->interface);
> > +		return -EINVAL;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int bcmgenet_eth_probe(struct udevice *dev)
> > +{
> > +	struct eth_pdata *pdata = dev_get_platdata(dev);
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	ofnode mdio_node;
> > +	const char *name;
> > +	u32 reg;
> > +	int ret;
> > +	u8 major;
> > +
> > +	priv->mac_reg = map_physmem(pdata->iobase, SZ_64K, MAP_NOCACHE);
> > +	priv->interface = pdata->phy_interface;
> > +	priv->speed = pdata->max_speed;
> > +
> > +	/* Read GENET HW version */
> > +	reg = readl_relaxed(priv->mac_reg + SYS_REV_CTRL);
> > +	major = (reg >> 24) & 0x0f;
> > +	if (major != 6) {
> > +		if (major == 5)
> > +			major = 4;
> > +		else if (major == 0)
> > +			major = 1;
> > +
> > +		printf("Unsupported GENETv%d.%d\n", major, (reg >> 16) & 0x0f);
> > +		return -ENODEV;
> > +	}
> > +
> > +	ret = bcmgenet_interface_set(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	mdio_node = dev_read_first_subnode(dev);
> > +	name = ofnode_get_name(mdio_node);
> > +
> > +	ret = bcmgenet_mdio_init(name, dev);
> > +	if (ret)
> > +		return ret;
> > +
> > +	priv->bus = miiphy_get_dev_by_name(name);
> > +
> > +	return bcmgenet_phy_init(priv, dev);
> > +}
> > +
> > +static void bcmgenet_gmac_eth_stop(struct udevice *dev)
> > +{
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +
> > +	clrbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> > +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL,
> > +		     1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT) | DMA_EN);
> > +}
> > +
> > +static const struct eth_ops bcmgenet_gmac_eth_ops = {
> > +	.start                  = bcmgenet_gmac_eth_start,
> > +	.write_hwaddr           = bcmgenet_gmac_write_hwaddr,
> > +	.send                   = bcmgenet_gmac_eth_send,
> > +	.recv                   = bcmgenet_gmac_eth_recv,
> > +	.free_pkt               = bcmgenet_gmac_free_pkt,
> > +	.stop                   = bcmgenet_gmac_eth_stop,
> > +};
> > +
> > +static int bcmgenet_eth_ofdata_to_platdata(struct udevice *dev)
> > +{
> > +	struct eth_pdata *pdata = dev_get_platdata(dev);
> > +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> > +	struct ofnode_phandle_args phy_node;
> > +	const char *phy_mode;
> > +	int ret;
> > +
> > +	pdata->iobase = dev_read_addr(dev);  
> 
> I suggest to change the type of pdata->iobase to void __iomem * and use
> dev_remap_addr(). This saves you the manual map_physmem() in
> bcmgenet_eth_probe(). Also dev_remap_addr() uses the correct register
> size from DT instead of the hard-coded SZ_64K.

I see your point, but was wondering about the separation between ofdata_to_platdata and the probe routine. The former is just supposed to collect all the data, the latter to actually instantiate the device. So reading the address from the DT is separate from mapping the region.

Anyway I guess it's not a showstopper that I want to respin the series for, so could you send a follow-up patch? Then we could have the discussion there.

Cheers,
Andre.

> 
> > +
> > +	/* Get phy mode from DT */
> > +	pdata->phy_interface = -1;
> > +	phy_mode = dev_read_string(dev, "phy-mode");
> > +	if (phy_mode)
> > +		pdata->phy_interface = phy_get_interface_by_name(phy_mode);
> > +	if (pdata->phy_interface == -1) {
> > +		debug("%s: Invalid PHY interface '%s'\n", __func__, phy_mode);
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
> > +					 &phy_node);
> > +	if (!ret) {
> > +		ofnode_read_s32(phy_node.node, "reg", &priv->phyaddr);
> > +		ofnode_read_s32(phy_node.node, "max-speed", &pdata->max_speed);
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +/* The BCM2711 implementation has a limited burst length compared to a generic
> > + * GENETv5 version, but we go with that shorter value (8) in both cases, for
> > + * the sake of simplicity.
> > + */
> > +static const struct udevice_id bcmgenet_eth_ids[] = {
> > +	{.compatible = "brcm,genet-v5"},
> > +	{.compatible = "brcm,bcm2711-genet-v5"},
> > +	{}
> > +};
> > +
> > +U_BOOT_DRIVER(eth_bcmgenet) = {
> > +	.name   = "eth_bcmgenet",
> > +	.id     = UCLASS_ETH,
> > +	.of_match = bcmgenet_eth_ids,
> > +	.ofdata_to_platdata = bcmgenet_eth_ofdata_to_platdata,
> > +	.probe  = bcmgenet_eth_probe,
> > +	.ops    = &bcmgenet_gmac_eth_ops,
> > +	.priv_auto_alloc_size = sizeof(struct bcmgenet_eth_priv),
> > +	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
> > +	.flags = DM_FLAG_ALLOC_PRIV_DMA,
> > +};
> >   
>
Daniel Schwierzeck Jan. 22, 2020, 5:22 p.m. | #4
Am 22.01.20 um 16:36 schrieb Andre Przywara:
> On Wed, 22 Jan 2020 16:02:22 +0100
> Daniel Schwierzeck <daniel.schwierzeck at gmail.com> wrote:
> 
> Hi Daniel,
> 
>> Am 17.01.20 um 02:20 schrieb Andre Przywara:
>>> From: Amit Singh Tomar <amittomer25 at gmail.com>
>>>
>>> The Broadcom GENET Ethernet MACs are used in several MIPS based SoCs
>>> and in the Broadcom 2711/2838 SoC used on the Raspberry Pi 4.
>>> There is no publicly available documentation, so this driver is based
>>> on the Linux driver. Compared to that the queue management is
>>> drastically simplified, also we only support version 5 of the IP and
>>> RGMII connections between MAC and PHY, as used on the RPi4.
>>>
>>> Signed-off-by: Amit Singh Tomar <amittomer25 at gmail.com>
>>> Reviewed-by: Andre Przywara <andre.przywara at arm.com>
>>> [Andre: heavy cleanup and a few fixes]
>>> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
>>> ---
>>>  drivers/net/Kconfig    |   7 +
>>>  drivers/net/Makefile   |   1 +
>>>  drivers/net/bcmgenet.c | 722 +++++++++++++++++++++++++++++++++++++++++++++++++
>>>  3 files changed, 730 insertions(+)
>>>  create mode 100644 drivers/net/bcmgenet.c  
>>
>> Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>
> 
> Many thanks!
> 
>>>
>>> diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
>>> index 01d087f229..4d1013c984 100644
>>> --- a/drivers/net/Kconfig
>>> +++ b/drivers/net/Kconfig
>>> @@ -136,6 +136,13 @@ config BCM6368_ETH
>>>  	help
>>>  	  This driver supports the BCM6368 Ethernet MAC.
>>>  
>>> +config BCMGENET
>>> +	bool "BCMGENET V5 support"
>>> +	depends on DM_ETH  
>>
>> maybe this should be limited to the supported SoC's?
>>
>> e.g.  depends on DM_ETH && ARCH_BCM283X
> 
> Technically this would not be correct: Nothing in the driver *code* depends on the Broadcom 2711 SoC. It uses generic accessors for the MMIO registers and the probe function is using generic DM routines. The rest is GENET driver code, which would even work on other architectures (hence the endianess changes).
> It would be a different story if we would take any 2711 specific shortcuts in the code, say poking some special hardcoded register to configure some clocks or the like.
> 
> Or is there any actual problem that you are thinking about, that would require this to be restricted?

Without the Kconfig dependency the config entry for BCMGENET would
always show up in "make menuconfig" under "Network devices". Or BCMGENET
could be automatically selected by a "make oldconfig" or "make
randconfig" in unrelated board configs. That doesn't make much sense if
BCMGENET is only ever found in Broadcom SoC's. Thus you should consider
to limit the config option to the Broadcom platforms. Without that
limitation you should add at least a "default n" line to not enable that
driver per default on unrelated boards.

> 
>>
>>> +	select PHYLIB
>>> +	help
>>> +	  This driver supports the BCMGENET Ethernet MAC.
>>> +
>>>  config DWC_ETH_QOS
>>>  	bool "Synopsys DWC Ethernet QOS device support"
>>>  	depends on DM_ETH
>>> diff --git a/drivers/net/Makefile b/drivers/net/Makefile
>>> index 30991834ec..6e0a68834d 100644
>>> --- a/drivers/net/Makefile
>>> +++ b/drivers/net/Makefile
>>> @@ -8,6 +8,7 @@ obj-$(CONFIG_AG7XXX) += ag7xxx.o
>>>  obj-$(CONFIG_ARMADA100_FEC) += armada100_fec.o
>>>  obj-$(CONFIG_BCM6348_ETH) += bcm6348-eth.o
>>>  obj-$(CONFIG_BCM6368_ETH) += bcm6368-eth.o
>>> +obj-$(CONFIG_BCMGENET) += bcmgenet.o
>>>  obj-$(CONFIG_DRIVER_AT91EMAC) += at91_emac.o
>>>  obj-$(CONFIG_DRIVER_AX88180) += ax88180.o
>>>  obj-$(CONFIG_BCM_SF2_ETH) += bcm-sf2-eth.o
>>> diff --git a/drivers/net/bcmgenet.c b/drivers/net/bcmgenet.c
>>> new file mode 100644
>>> index 0000000000..4f8f190071
>>> --- /dev/null
>>> +++ b/drivers/net/bcmgenet.c
>>> @@ -0,0 +1,722 @@
>>> +// SPDX-License-Identifier: GPL-2.0+
>>> +/*
>>> + * Copyright (C) 2019 Amit Singh Tomar <amittomer25 at gmail.com>
>>> + *
>>> + * Driver for Broadcom GENETv5 Ethernet controller (as found on the RPi4)
>>> + * This driver is based on the Linux driver:
>>> + *      drivers/net/ethernet/broadcom/genet/bcmgenet.c
>>> + *      which is: Copyright (c) 2014-2017 Broadcom
>>> + *
>>> + * The hardware supports multiple queues (16 priority queues and one
>>> + * default queue), both for RX and TX. There are 256 DMA descriptors (both
>>> + * for TX and RX), and they live in MMIO registers. The hardware allows
>>> + * assigning descriptor ranges to queues, but we choose the most simple setup:
>>> + * All 256 descriptors are assigned to the default queue (#16).
>>> + * Also the Linux driver supports multiple generations of the MAC, whereas
>>> + * we only support v5, as used in the Raspberry Pi 4.
>>> + */
>>> +
>>> +#include <asm/io.h>
>>> +#include <clk.h>
>>> +#include <cpu_func.h>
>>> +#include <dm.h>
>>> +#include <fdt_support.h>
>>> +#include <linux/err.h>
>>> +#include <malloc.h>
>>> +#include <miiphy.h>
>>> +#include <net.h>
>>> +#include <dm/of_access.h>
>>> +#include <dm/ofnode.h>
>>> +#include <linux/iopoll.h>
>>> +#include <linux/sizes.h>
>>> +#include <asm/dma-mapping.h>
>>> +#include <wait_bit.h>
>>> +
>>> +/* Register definitions derived from Linux source */
>>> +#define SYS_REV_CTRL			0x00
>>> +
>>> +#define SYS_PORT_CTRL			0x04
>>> +#define PORT_MODE_EXT_GPHY		3
>>> +
>>> +#define GENET_SYS_OFF			0x0000
>>> +#define SYS_RBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x08)
>>> +#define SYS_TBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x0c)
>>> +
>>> +#define GENET_EXT_OFF			0x0080
>>> +#define EXT_RGMII_OOB_CTRL		(GENET_EXT_OFF + 0x0c)
>>> +#define RGMII_LINK			BIT(4)
>>> +#define OOB_DISABLE			BIT(5)
>>> +#define RGMII_MODE_EN			BIT(6)
>>> +#define ID_MODE_DIS			BIT(16)
>>> +
>>> +#define GENET_RBUF_OFF			0x0300
>>> +#define RBUF_TBUF_SIZE_CTRL		(GENET_RBUF_OFF + 0xb4)
>>> +#define RBUF_CTRL			(GENET_RBUF_OFF + 0x00)
>>> +#define RBUF_ALIGN_2B			BIT(1)
>>> +
>>> +#define GENET_UMAC_OFF			0x0800
>>> +#define UMAC_MIB_CTRL			(GENET_UMAC_OFF + 0x580)
>>> +#define UMAC_MAX_FRAME_LEN		(GENET_UMAC_OFF + 0x014)
>>> +#define UMAC_MAC0			(GENET_UMAC_OFF + 0x00c)
>>> +#define UMAC_MAC1			(GENET_UMAC_OFF + 0x010)
>>> +#define UMAC_CMD			(GENET_UMAC_OFF + 0x008)
>>> +#define MDIO_CMD			(GENET_UMAC_OFF + 0x614)
>>> +#define UMAC_TX_FLUSH			(GENET_UMAC_OFF + 0x334)
>>> +#define MDIO_START_BUSY			BIT(29)
>>> +#define MDIO_READ_FAIL			BIT(28)
>>> +#define MDIO_RD				(2 << 26)
>>> +#define MDIO_WR				BIT(26)
>>> +#define MDIO_PMD_SHIFT			21
>>> +#define MDIO_PMD_MASK			0x1f
>>> +#define MDIO_REG_SHIFT			16
>>> +#define MDIO_REG_MASK			0x1f
>>> +
>>> +#define CMD_TX_EN			BIT(0)
>>> +#define CMD_RX_EN			BIT(1)
>>> +#define UMAC_SPEED_10			0
>>> +#define UMAC_SPEED_100			1
>>> +#define UMAC_SPEED_1000			2
>>> +#define UMAC_SPEED_2500			3
>>> +#define CMD_SPEED_SHIFT			2
>>> +#define CMD_SPEED_MASK			3
>>> +#define CMD_SW_RESET			BIT(13)
>>> +#define CMD_LCL_LOOP_EN			BIT(15)
>>> +#define CMD_TX_EN			BIT(0)
>>> +#define CMD_RX_EN			BIT(1)
>>> +
>>> +#define MIB_RESET_RX			BIT(0)
>>> +#define MIB_RESET_RUNT			BIT(1)
>>> +#define MIB_RESET_TX			BIT(2)
>>> +
>>> +/* total number of Buffer Descriptors, same for Rx/Tx */
>>> +#define TOTAL_DESCS			256
>>> +#define RX_DESCS			TOTAL_DESCS
>>> +#define TX_DESCS			TOTAL_DESCS
>>> +
>>> +#define DEFAULT_Q			0x10
>>> +
>>> +/* Body(1500) + EH_SIZE(14) + VLANTAG(4) + BRCMTAG(6) + FCS(4) = 1528.
>>> + * 1536 is multiple of 256 bytes
>>> + */
>>> +#define ENET_BRCM_TAG_LEN		6
>>> +#define ENET_PAD			8
>>> +#define ENET_MAX_MTU_SIZE		(ETH_DATA_LEN + ETH_HLEN +	 \
>>> +					 VLAN_HLEN + ENET_BRCM_TAG_LEN + \
>>> +					 ETH_FCS_LEN + ENET_PAD)
>>> +
>>> +/* Tx/Rx Dma Descriptor common bits */
>>> +#define DMA_EN				BIT(0)
>>> +#define DMA_RING_BUF_EN_SHIFT		0x01
>>> +#define DMA_RING_BUF_EN_MASK		0xffff
>>> +#define DMA_BUFLENGTH_MASK		0x0fff
>>> +#define DMA_BUFLENGTH_SHIFT		16
>>> +#define DMA_RING_SIZE_SHIFT		16
>>> +#define DMA_OWN				0x8000
>>> +#define DMA_EOP				0x4000
>>> +#define DMA_SOP				0x2000
>>> +#define DMA_WRAP			0x1000
>>> +#define DMA_MAX_BURST_LENGTH		0x8
>>> +/* Tx specific DMA descriptor bits */
>>> +#define DMA_TX_UNDERRUN			0x0200
>>> +#define DMA_TX_APPEND_CRC		0x0040
>>> +#define DMA_TX_OW_CRC			0x0020
>>> +#define DMA_TX_DO_CSUM			0x0010
>>> +#define DMA_TX_QTAG_SHIFT		7
>>> +
>>> +/* DMA rings size */
>>> +#define DMA_RING_SIZE			0x40
>>> +#define DMA_RINGS_SIZE			(DMA_RING_SIZE * (DEFAULT_Q + 1))
>>> +
>>> +/* DMA descriptor */
>>> +#define DMA_DESC_LENGTH_STATUS		0x00
>>> +#define DMA_DESC_ADDRESS_LO		0x04
>>> +#define DMA_DESC_ADDRESS_HI		0x08
>>> +#define DMA_DESC_SIZE			12
>>> +
>>> +#define GENET_RX_OFF			0x2000
>>> +#define GENET_RDMA_REG_OFF					\
>>> +	(GENET_RX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
>>> +#define GENET_TX_OFF			0x4000
>>> +#define GENET_TDMA_REG_OFF					\
>>> +	(GENET_TX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
>>> +
>>> +#define DMA_FC_THRESH_HI		(RX_DESCS >> 4)
>>> +#define DMA_FC_THRESH_LO		5
>>> +#define DMA_FC_THRESH_VALUE		((DMA_FC_THRESH_LO << 16) |	\
>>> +					  DMA_FC_THRESH_HI)
>>> +
>>> +#define DMA_XOFF_THRESHOLD_SHIFT	16
>>> +
>>> +#define TDMA_RING_REG_BASE					\
>>> +	(GENET_TDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
>>> +#define TDMA_READ_PTR			(TDMA_RING_REG_BASE + 0x00)
>>> +#define TDMA_CONS_INDEX			(TDMA_RING_REG_BASE + 0x08)
>>> +#define TDMA_PROD_INDEX			(TDMA_RING_REG_BASE + 0x0c)
>>> +#define DMA_RING_BUF_SIZE		0x10
>>> +#define DMA_START_ADDR			0x14
>>> +#define DMA_END_ADDR			0x1c
>>> +#define DMA_MBUF_DONE_THRESH		0x24
>>> +#define TDMA_FLOW_PERIOD		(TDMA_RING_REG_BASE + 0x28)
>>> +#define TDMA_WRITE_PTR			(TDMA_RING_REG_BASE + 0x2c)
>>> +
>>> +#define RDMA_RING_REG_BASE					\
>>> +	(GENET_RDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
>>> +#define RDMA_WRITE_PTR			(RDMA_RING_REG_BASE + 0x00)
>>> +#define RDMA_PROD_INDEX			(RDMA_RING_REG_BASE + 0x08)
>>> +#define RDMA_CONS_INDEX			(RDMA_RING_REG_BASE + 0x0c)
>>> +#define RDMA_XON_XOFF_THRESH		(RDMA_RING_REG_BASE + 0x28)
>>> +#define RDMA_READ_PTR			(RDMA_RING_REG_BASE + 0x2c)
>>> +
>>> +#define TDMA_REG_BASE			(GENET_TDMA_REG_OFF + DMA_RINGS_SIZE)
>>> +#define RDMA_REG_BASE			(GENET_RDMA_REG_OFF + DMA_RINGS_SIZE)
>>> +#define DMA_RING_CFG			0x00
>>> +#define DMA_CTRL			0x04
>>> +#define DMA_SCB_BURST_SIZE		0x0c
>>> +
>>> +#define RX_BUF_LENGTH			2048
>>> +#define RX_TOTAL_BUFSIZE		(RX_BUF_LENGTH * RX_DESCS)
>>> +#define RX_BUF_OFFSET			2
>>> +
>>> +struct bcmgenet_eth_priv {
>>> +	char rxbuffer[RX_TOTAL_BUFSIZE] __aligned(ARCH_DMA_MINALIGN);
>>> +	void *mac_reg;
>>> +	void *tx_desc_base;
>>> +	void *rx_desc_base;
>>> +	int tx_index;
>>> +	int rx_index;
>>> +	int c_index;
>>> +	int phyaddr;
>>> +	u32 interface;
>>> +	u32 speed;
>>> +	struct phy_device *phydev;
>>> +	struct mii_dev *bus;
>>> +};
>>> +
>>> +static void bcmgenet_umac_reset(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	u32 reg;
>>> +
>>> +	reg = readl(priv->mac_reg + SYS_RBUF_FLUSH_CTRL);
>>> +	reg |= BIT(1);
>>> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
>>> +	udelay(10);
>>> +
>>> +	reg &= ~BIT(1);
>>> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
>>> +	udelay(10);
>>> +
>>> +	writel(0, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
>>> +	udelay(10);
>>> +
>>> +	writel(0, priv->mac_reg + UMAC_CMD);
>>> +
>>> +	writel(CMD_SW_RESET | CMD_LCL_LOOP_EN, priv->mac_reg + UMAC_CMD);
>>> +	udelay(2);
>>> +	writel(0, priv->mac_reg + UMAC_CMD);
>>> +
>>> +	/* clear tx/rx counter */
>>> +	writel(MIB_RESET_RX | MIB_RESET_TX | MIB_RESET_RUNT,
>>> +	       priv->mac_reg + UMAC_MIB_CTRL);
>>> +	writel(0, priv->mac_reg + UMAC_MIB_CTRL);
>>> +
>>> +	writel(ENET_MAX_MTU_SIZE, priv->mac_reg + UMAC_MAX_FRAME_LEN);
>>> +
>>> +	/* init rx registers, enable ip header optimization */
>>> +	reg = readl(priv->mac_reg + RBUF_CTRL);
>>> +	reg |= RBUF_ALIGN_2B;
>>> +	writel(reg, (priv->mac_reg + RBUF_CTRL));
>>> +
>>> +	writel(1, (priv->mac_reg + RBUF_TBUF_SIZE_CTRL));
>>> +}
>>> +
>>> +static int bcmgenet_gmac_write_hwaddr(struct udevice *dev)
>>> +{
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	struct eth_pdata *pdata = dev_get_platdata(dev);
>>> +	uchar *addr = pdata->enetaddr;
>>> +	u32 reg;
>>> +
>>> +	reg = addr[0] << 24 | addr[1] << 16 | addr[2] << 8 | addr[3];
>>> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC0);
>>> +
>>> +	reg = addr[4] << 8 | addr[5];
>>> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC1);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static void bcmgenet_disable_dma(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL, DMA_EN);
>>> +	clrbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, DMA_EN);
>>> +
>>> +	writel(1, priv->mac_reg + UMAC_TX_FLUSH);
>>> +	udelay(10);
>>> +	writel(0, priv->mac_reg + UMAC_TX_FLUSH);
>>> +}
>>> +
>>> +static void bcmgenet_enable_dma(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	u32 dma_ctrl = (1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT)) | DMA_EN;
>>> +
>>> +	writel(dma_ctrl, priv->mac_reg + TDMA_REG_BASE + DMA_CTRL);
>>> +
>>> +	setbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, dma_ctrl);
>>> +}
>>> +
>>> +static int bcmgenet_gmac_eth_send(struct udevice *dev, void *packet, int length)
>>> +{
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	void *desc_base = priv->tx_desc_base + priv->tx_index * DMA_DESC_SIZE;
>>> +	u32 len_stat = length << DMA_BUFLENGTH_SHIFT;
>>> +	ulong packet_aligned = rounddown((ulong)packet, ARCH_DMA_MINALIGN);
>>> +	u32 prod_index, cons;
>>> +	u32 tries = 100;
>>> +
>>> +	prod_index = readl(priv->mac_reg + TDMA_PROD_INDEX);
>>> +
>>> +	/* There is actually no reason for the rounding here, but the ARMv7
>>> +	 * implementation of flush_dcache_range() checks for aligned
>>> +	 * boundaries of the flushed range.
>>> +	 * Adjust them here to pass that check and avoid misleading messages.
>>> +	 */
>>> +	flush_dcache_range(packet_aligned,
>>> +			   packet_aligned + roundup(length, ARCH_DMA_MINALIGN));
>>> +
>>> +	len_stat |= 0x3F << DMA_TX_QTAG_SHIFT;
>>> +	len_stat |= DMA_TX_APPEND_CRC | DMA_SOP | DMA_EOP;
>>> +
>>> +	/* Set-up packet for transmission */
>>> +	writel(lower_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_LO));
>>> +	writel(upper_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_HI));
>>> +	writel(len_stat, (desc_base + DMA_DESC_LENGTH_STATUS));
>>> +
>>> +	/* Increment index and start transmission */
>>> +	if (++priv->tx_index >= TX_DESCS)
>>> +		priv->tx_index = 0;
>>> +
>>> +	prod_index++;
>>> +
>>> +	/* Start Transmisson */
>>> +	writel(prod_index, priv->mac_reg + TDMA_PROD_INDEX);
>>> +
>>> +	do {
>>> +		cons = readl(priv->mac_reg + TDMA_CONS_INDEX);
>>> +	} while ((cons & 0xffff) < prod_index && --tries);
>>> +	if (!tries)
>>> +		return -ETIMEDOUT;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +/* Check whether all cache lines affected by an invalidate are within
>>> + * the buffer, to make sure we don't accidentally lose unrelated dirty
>>> + * data stored nearby.
>>> + * Alignment of the buffer start address will be checked in the implementation
>>> + * of invalidate_dcache_range().
>>> + */
>>> +static void invalidate_dcache_check(unsigned long addr, size_t size,
>>> +				    size_t buffer_size)
>>> +{
>>> +	size_t inval_size = roundup(size, ARCH_DMA_MINALIGN);
>>> +
>>> +	if (unlikely(inval_size > buffer_size))
>>> +		printf("WARNING: Cache invalidate area exceeds buffer size\n");
>>> +
>>> +	invalidate_dcache_range(addr, addr + inval_size);
>>> +}
>>> +
>>> +static int bcmgenet_gmac_eth_recv(struct udevice *dev,
>>> +				  int flags, uchar **packetp)
>>> +{
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	void *desc_base = priv->rx_desc_base + priv->rx_index * DMA_DESC_SIZE;
>>> +	u32 prod_index = readl(priv->mac_reg + RDMA_PROD_INDEX);
>>> +	u32 length, addr;
>>> +
>>> +	if (prod_index == priv->c_index)
>>> +		return -EAGAIN;
>>> +
>>> +	length = readl(desc_base + DMA_DESC_LENGTH_STATUS);
>>> +	length = (length >> DMA_BUFLENGTH_SHIFT) & DMA_BUFLENGTH_MASK;
>>> +	addr = readl(desc_base + DMA_DESC_ADDRESS_LO);
>>> +
>>> +	invalidate_dcache_check(addr, length, RX_BUF_LENGTH);
>>> +
>>> +	/* To cater for the IP header alignment the hardware does.
>>> +	 * This would actually not be needed if we don't program
>>> +	 * RBUF_ALIGN_2B
>>> +	 */
>>> +	*packetp = (uchar *)(ulong)addr + RX_BUF_OFFSET;
>>> +
>>> +	return length - RX_BUF_OFFSET;
>>> +}
>>> +
>>> +static int bcmgenet_gmac_free_pkt(struct udevice *dev, uchar *packet,
>>> +				  int length)
>>> +{
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +
>>> +	/* Tell the MAC we have consumed that last receive buffer. */
>>> +	priv->c_index = (priv->c_index + 1) & 0xFFFF;
>>> +	writel(priv->c_index, priv->mac_reg + RDMA_CONS_INDEX);
>>> +
>>> +	/* Forward our descriptor pointer, wrapping around if needed. */
>>> +	if (++priv->rx_index >= RX_DESCS)
>>> +		priv->rx_index = 0;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static void rx_descs_init(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	char *rxbuffs = &priv->rxbuffer[0];
>>> +	u32 len_stat, i;
>>> +	void *desc_base = priv->rx_desc_base;
>>> +
>>> +	priv->c_index = 0;
>>> +
>>> +	len_stat = (RX_BUF_LENGTH << DMA_BUFLENGTH_SHIFT) | DMA_OWN;
>>> +
>>> +	for (i = 0; i < RX_DESCS; i++) {
>>> +		writel(lower_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
>>> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_LO);
>>> +		writel(upper_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
>>> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_HI);
>>> +		writel(len_stat,
>>> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_LENGTH_STATUS);
>>> +	}
>>> +}
>>> +
>>> +static void rx_ring_init(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	writel(DMA_MAX_BURST_LENGTH,
>>> +	       priv->mac_reg + RDMA_REG_BASE + DMA_SCB_BURST_SIZE);
>>> +
>>> +	writel(0x0, priv->mac_reg + RDMA_RING_REG_BASE + DMA_START_ADDR);
>>> +	writel(0x0, priv->mac_reg + RDMA_READ_PTR);
>>> +	writel(0x0, priv->mac_reg + RDMA_WRITE_PTR);
>>> +	writel(RX_DESCS * DMA_DESC_SIZE / 4 - 1,
>>> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_END_ADDR);
>>> +
>>> +	writel(0x0, priv->mac_reg + RDMA_PROD_INDEX);
>>> +	writel(0x0, priv->mac_reg + RDMA_CONS_INDEX);
>>> +	writel((RX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
>>> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
>>> +	writel(DMA_FC_THRESH_VALUE, priv->mac_reg + RDMA_XON_XOFF_THRESH);
>>> +	writel(1 << DEFAULT_Q, priv->mac_reg + RDMA_REG_BASE + DMA_RING_CFG);
>>> +}
>>> +
>>> +static void tx_ring_init(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	writel(DMA_MAX_BURST_LENGTH,
>>> +	       priv->mac_reg + TDMA_REG_BASE + DMA_SCB_BURST_SIZE);
>>> +
>>> +	writel(0x0, priv->mac_reg + TDMA_RING_REG_BASE + DMA_START_ADDR);
>>> +	writel(0x0, priv->mac_reg + TDMA_READ_PTR);
>>> +	writel(0x0, priv->mac_reg + TDMA_WRITE_PTR);
>>> +	writel(TX_DESCS * DMA_DESC_SIZE / 4 - 1,
>>> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_END_ADDR);
>>> +	writel(0x0, priv->mac_reg + TDMA_PROD_INDEX);
>>> +	writel(0x0, priv->mac_reg + TDMA_CONS_INDEX);
>>> +	writel(0x1, priv->mac_reg + TDMA_RING_REG_BASE + DMA_MBUF_DONE_THRESH);
>>> +	writel(0x0, priv->mac_reg + TDMA_FLOW_PERIOD);
>>> +	writel((TX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
>>> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
>>> +
>>> +	writel(1 << DEFAULT_Q, priv->mac_reg + TDMA_REG_BASE + DMA_RING_CFG);
>>> +}
>>> +
>>> +static int bcmgenet_adjust_link(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	struct phy_device *phy_dev = priv->phydev;
>>> +	u32 speed;
>>> +
>>> +	switch (phy_dev->speed) {
>>> +	case SPEED_1000:
>>> +		speed = UMAC_SPEED_1000;
>>> +		break;
>>> +	case SPEED_100:
>>> +		speed = UMAC_SPEED_100;
>>> +		break;
>>> +	case SPEED_10:
>>> +		speed = UMAC_SPEED_10;
>>> +		break;
>>> +	default:
>>> +		printf("bcmgenet: Unsupported PHY speed: %d\n", phy_dev->speed);
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	clrsetbits_32(priv->mac_reg + EXT_RGMII_OOB_CTRL, OOB_DISABLE,
>>> +			RGMII_LINK | RGMII_MODE_EN | ID_MODE_DIS);
>>> +
>>> +	writel(speed << CMD_SPEED_SHIFT, (priv->mac_reg + UMAC_CMD));
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int bcmgenet_gmac_eth_start(struct udevice *dev)
>>> +{
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	int ret;
>>> +
>>> +	priv->tx_desc_base = priv->mac_reg + GENET_TX_OFF;
>>> +	priv->rx_desc_base = priv->mac_reg + GENET_RX_OFF;
>>> +	priv->tx_index = 0x0;
>>> +	priv->rx_index = 0x0;
>>> +
>>> +	bcmgenet_umac_reset(priv);
>>> +
>>> +	bcmgenet_gmac_write_hwaddr(dev);
>>> +
>>> +	/* Disable RX/TX DMA and flush TX queues */
>>> +	bcmgenet_disable_dma(priv);
>>> +
>>> +	rx_ring_init(priv);
>>> +	rx_descs_init(priv);
>>> +
>>> +	tx_ring_init(priv);
>>> +
>>> +	/* Enable RX/TX DMA */
>>> +	bcmgenet_enable_dma(priv);
>>> +
>>> +	/* read PHY properties over the wire from generic PHY set-up */
>>> +	ret = phy_startup(priv->phydev);
>>> +	if (ret) {
>>> +		printf("bcmgenet: PHY startup failed: %d\n", ret);
>>> +		return ret;
>>> +	}
>>> +
>>> +	/* Update MAC registers based on PHY property */
>>> +	ret = bcmgenet_adjust_link(priv);
>>> +	if (ret) {
>>> +		printf("bcmgenet: adjust PHY link failed: %d\n", ret);
>>> +		return ret;
>>> +	}
>>> +
>>> +	/* Enable Rx/Tx */
>>> +	setbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int bcmgenet_phy_init(struct bcmgenet_eth_priv *priv, void *dev)
>>> +{
>>> +	struct phy_device *phydev;
>>> +	int ret;
>>> +
>>> +	phydev = phy_connect(priv->bus, priv->phyaddr, dev, priv->interface);
>>> +	if (!phydev)
>>> +		return -ENODEV;
>>> +
>>> +	phydev->supported &= PHY_GBIT_FEATURES;
>>> +	if (priv->speed) {
>>> +		ret = phy_set_supported(priv->phydev, priv->speed);
>>> +		if (ret)
>>> +			return ret;
>>> +	}
>>> +	phydev->advertising = phydev->supported;
>>> +
>>> +	phy_connect_dev(phydev, dev);
>>> +
>>> +	priv->phydev = phydev;
>>> +	phy_config(priv->phydev);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static void bcmgenet_mdio_start(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	setbits_32(priv->mac_reg + MDIO_CMD, MDIO_START_BUSY);
>>> +}
>>> +
>>> +static int bcmgenet_mdio_write(struct mii_dev *bus, int addr, int devad,
>>> +			       int reg, u16 value)
>>> +{
>>> +	struct udevice *dev = bus->priv;
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	u32 val;
>>> +
>>> +	/* Prepare the read operation */
>>> +	val = MDIO_WR | (addr << MDIO_PMD_SHIFT) |
>>> +		(reg << MDIO_REG_SHIFT) | (0xffff & value);
>>> +	writel_relaxed(val,  priv->mac_reg + MDIO_CMD);
>>> +
>>> +	/* Start MDIO transaction */
>>> +	bcmgenet_mdio_start(priv);
>>> +
>>> +	return wait_for_bit_32(priv->mac_reg + MDIO_CMD,
>>> +			       MDIO_START_BUSY, false, 20, true);
>>> +}
>>> +
>>> +static int bcmgenet_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
>>> +{
>>> +	struct udevice *dev = bus->priv;
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	u32 val;
>>> +	int ret;
>>> +
>>> +	/* Prepare the read operation */
>>> +	val = MDIO_RD | (addr << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
>>> +	writel_relaxed(val, priv->mac_reg + MDIO_CMD);
>>> +
>>> +	/* Start MDIO transaction */
>>> +	bcmgenet_mdio_start(priv);
>>> +
>>> +	ret = wait_for_bit_32(priv->mac_reg + MDIO_CMD,
>>> +			      MDIO_START_BUSY, false, 20, true);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	val = readl_relaxed(priv->mac_reg + MDIO_CMD);
>>> +
>>> +	return val & 0xffff;
>>> +}
>>> +
>>> +static int bcmgenet_mdio_init(const char *name, struct udevice *priv)
>>> +{
>>> +	struct mii_dev *bus = mdio_alloc();
>>> +
>>> +	if (!bus) {
>>> +		debug("Failed to allocate MDIO bus\n");
>>> +		return -ENOMEM;
>>> +	}
>>> +
>>> +	bus->read = bcmgenet_mdio_read;
>>> +	bus->write = bcmgenet_mdio_write;
>>> +	snprintf(bus->name, sizeof(bus->name), name);
>>> +	bus->priv = (void *)priv;
>>> +
>>> +	return mdio_register(bus);
>>> +}
>>> +
>>> +/* We only support RGMII (as used on the RPi4). */
>>> +static int bcmgenet_interface_set(struct bcmgenet_eth_priv *priv)
>>> +{
>>> +	phy_interface_t phy_mode = priv->interface;
>>> +
>>> +	switch (phy_mode) {
>>> +	case PHY_INTERFACE_MODE_RGMII:
>>> +	case PHY_INTERFACE_MODE_RGMII_RXID:
>>> +		writel(PORT_MODE_EXT_GPHY, priv->mac_reg + SYS_PORT_CTRL);
>>> +		break;
>>> +	default:
>>> +		printf("unknown phy mode: %d\n", priv->interface);
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int bcmgenet_eth_probe(struct udevice *dev)
>>> +{
>>> +	struct eth_pdata *pdata = dev_get_platdata(dev);
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	ofnode mdio_node;
>>> +	const char *name;
>>> +	u32 reg;
>>> +	int ret;
>>> +	u8 major;
>>> +
>>> +	priv->mac_reg = map_physmem(pdata->iobase, SZ_64K, MAP_NOCACHE);
>>> +	priv->interface = pdata->phy_interface;
>>> +	priv->speed = pdata->max_speed;
>>> +
>>> +	/* Read GENET HW version */
>>> +	reg = readl_relaxed(priv->mac_reg + SYS_REV_CTRL);
>>> +	major = (reg >> 24) & 0x0f;
>>> +	if (major != 6) {
>>> +		if (major == 5)
>>> +			major = 4;
>>> +		else if (major == 0)
>>> +			major = 1;
>>> +
>>> +		printf("Unsupported GENETv%d.%d\n", major, (reg >> 16) & 0x0f);
>>> +		return -ENODEV;
>>> +	}
>>> +
>>> +	ret = bcmgenet_interface_set(priv);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	mdio_node = dev_read_first_subnode(dev);
>>> +	name = ofnode_get_name(mdio_node);
>>> +
>>> +	ret = bcmgenet_mdio_init(name, dev);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	priv->bus = miiphy_get_dev_by_name(name);
>>> +
>>> +	return bcmgenet_phy_init(priv, dev);
>>> +}
>>> +
>>> +static void bcmgenet_gmac_eth_stop(struct udevice *dev)
>>> +{
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +
>>> +	clrbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
>>> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL,
>>> +		     1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT) | DMA_EN);
>>> +}
>>> +
>>> +static const struct eth_ops bcmgenet_gmac_eth_ops = {
>>> +	.start                  = bcmgenet_gmac_eth_start,
>>> +	.write_hwaddr           = bcmgenet_gmac_write_hwaddr,
>>> +	.send                   = bcmgenet_gmac_eth_send,
>>> +	.recv                   = bcmgenet_gmac_eth_recv,
>>> +	.free_pkt               = bcmgenet_gmac_free_pkt,
>>> +	.stop                   = bcmgenet_gmac_eth_stop,
>>> +};
>>> +
>>> +static int bcmgenet_eth_ofdata_to_platdata(struct udevice *dev)
>>> +{
>>> +	struct eth_pdata *pdata = dev_get_platdata(dev);
>>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
>>> +	struct ofnode_phandle_args phy_node;
>>> +	const char *phy_mode;
>>> +	int ret;
>>> +
>>> +	pdata->iobase = dev_read_addr(dev);  
>>
>> I suggest to change the type of pdata->iobase to void __iomem * and use
>> dev_remap_addr(). This saves you the manual map_physmem() in
>> bcmgenet_eth_probe(). Also dev_remap_addr() uses the correct register
>> size from DT instead of the hard-coded SZ_64K.
> 
> I see your point, but was wondering about the separation between ofdata_to_platdata and the probe routine. The former is just supposed to collect all the data, the latter to actually instantiate the device. So reading the address from the DT is separate from mapping the region.
> 
> Anyway I guess it's not a showstopper that I want to respin the series for, so could you send a follow-up patch? Then we could have the discussion there.
> 

It's not for me :D

AFAIK ofdata_to_platdata is optional and is only required if you
additionally need to support driver configuration without device-tree
(e.g. in a size-constained SPL). Usually you could put everything in the
probe function.

> 
>>
>>> +
>>> +	/* Get phy mode from DT */
>>> +	pdata->phy_interface = -1;
>>> +	phy_mode = dev_read_string(dev, "phy-mode");
>>> +	if (phy_mode)
>>> +		pdata->phy_interface = phy_get_interface_by_name(phy_mode);
>>> +	if (pdata->phy_interface == -1) {
>>> +		debug("%s: Invalid PHY interface '%s'\n", __func__, phy_mode);
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
>>> +					 &phy_node);
>>> +	if (!ret) {
>>> +		ofnode_read_s32(phy_node.node, "reg", &priv->phyaddr);
>>> +		ofnode_read_s32(phy_node.node, "max-speed", &pdata->max_speed);
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +/* The BCM2711 implementation has a limited burst length compared to a generic
>>> + * GENETv5 version, but we go with that shorter value (8) in both cases, for
>>> + * the sake of simplicity.
>>> + */
>>> +static const struct udevice_id bcmgenet_eth_ids[] = {
>>> +	{.compatible = "brcm,genet-v5"},
>>> +	{.compatible = "brcm,bcm2711-genet-v5"},
>>> +	{}
>>> +};
>>> +
>>> +U_BOOT_DRIVER(eth_bcmgenet) = {
>>> +	.name   = "eth_bcmgenet",
>>> +	.id     = UCLASS_ETH,
>>> +	.of_match = bcmgenet_eth_ids,
>>> +	.ofdata_to_platdata = bcmgenet_eth_ofdata_to_platdata,
>>> +	.probe  = bcmgenet_eth_probe,
>>> +	.ops    = &bcmgenet_gmac_eth_ops,
>>> +	.priv_auto_alloc_size = sizeof(struct bcmgenet_eth_priv),
>>> +	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
>>> +	.flags = DM_FLAG_ALLOC_PRIV_DMA,
>>> +};
>>>   
>>
>
Andre Przywara Jan. 22, 2020, 6 p.m. | #5
On Wed, 22 Jan 2020 18:22:47 +0100
Daniel Schwierzeck <daniel.schwierzeck at gmail.com> wrote:

Hi,

> Am 22.01.20 um 16:36 schrieb Andre Przywara:
> > On Wed, 22 Jan 2020 16:02:22 +0100
> > Daniel Schwierzeck <daniel.schwierzeck at gmail.com> wrote:
> > 
> > Hi Daniel,
> >   
> >> Am 17.01.20 um 02:20 schrieb Andre Przywara:  
> >>> From: Amit Singh Tomar <amittomer25 at gmail.com>
> >>>
> >>> The Broadcom GENET Ethernet MACs are used in several MIPS based SoCs
> >>> and in the Broadcom 2711/2838 SoC used on the Raspberry Pi 4.
> >>> There is no publicly available documentation, so this driver is based
> >>> on the Linux driver. Compared to that the queue management is
> >>> drastically simplified, also we only support version 5 of the IP and
> >>> RGMII connections between MAC and PHY, as used on the RPi4.
> >>>
> >>> Signed-off-by: Amit Singh Tomar <amittomer25 at gmail.com>
> >>> Reviewed-by: Andre Przywara <andre.przywara at arm.com>
> >>> [Andre: heavy cleanup and a few fixes]
> >>> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> >>> ---
> >>>  drivers/net/Kconfig    |   7 +
> >>>  drivers/net/Makefile   |   1 +
> >>>  drivers/net/bcmgenet.c | 722 +++++++++++++++++++++++++++++++++++++++++++++++++
> >>>  3 files changed, 730 insertions(+)
> >>>  create mode 100644 drivers/net/bcmgenet.c    
> >>
> >> Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>  
> > 
> > Many thanks!
> >   
> >>>
> >>> diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
> >>> index 01d087f229..4d1013c984 100644
> >>> --- a/drivers/net/Kconfig
> >>> +++ b/drivers/net/Kconfig
> >>> @@ -136,6 +136,13 @@ config BCM6368_ETH
> >>>  	help
> >>>  	  This driver supports the BCM6368 Ethernet MAC.
> >>>  
> >>> +config BCMGENET
> >>> +	bool "BCMGENET V5 support"
> >>> +	depends on DM_ETH    
> >>
> >> maybe this should be limited to the supported SoC's?
> >>
> >> e.g.  depends on DM_ETH && ARCH_BCM283X  
> > 
> > Technically this would not be correct: Nothing in the driver *code* depends on the Broadcom 2711 SoC. It uses generic accessors for the MMIO registers and the probe function is using generic DM routines. The rest is GENET driver code, which would even work on other architectures (hence the endianess changes).
> > It would be a different story if we would take any 2711 specific shortcuts in the code, say poking some special hardcoded register to configure some clocks or the like.
> > 
> > Or is there any actual problem that you are thinking about, that would require this to be restricted?  
> 
> Without the Kconfig dependency the config entry for BCMGENET would
> always show up in "make menuconfig" under "Network devices".

Yes, that's the idea. Because it's a driver for some piece of IP. And older versions of this IP were used in MIPS chips, reportedly.

> Or BCMGENET
> could be automatically selected by a "make oldconfig"

I was under the impression that "default n" is the behaviour when no default line is specified? So oldconfig or defconfig would never enable those devices?

> or "make randconfig" in unrelated board configs.

For randconfig: Yes please, compile this driver in, to get more (compile) test coverage. Shouldn't hurt, and you probably don't want to use such an image.

> That doesn't make much sense if BCMGENET is only ever found in Broadcom SoC's.

I don't know that for sure, and I don't think that "makes sense" or "only ever found in..." is within the scope of Kconfig. It's purely about technical dependencies, like: contains assembly code, accesses BCM2711 specific registers, requires a framework, etc.

> Thus you should consider
> to limit the config option to the Broadcom platforms. Without that
> limitation you should add at least a "default n" line to not enable that
> driver per default on unrelated boards.

I understand this sentence from Documentation/kbuild/kconfig-language.txt like it does this already:
"The default value deliberately defaults to 'n' in order to avoid bloating the
 build. With few exceptions, new config options should not change this. The
 intent is for "make oldconfig" to add as little as possible to the config from
 release to release."

Did this happen to be compiled in for you?

Cheers,
Andre.


> 
> >   
> >>  
> >>> +	select PHYLIB
> >>> +	help
> >>> +	  This driver supports the BCMGENET Ethernet MAC.
> >>> +
> >>>  config DWC_ETH_QOS
> >>>  	bool "Synopsys DWC Ethernet QOS device support"
> >>>  	depends on DM_ETH
> >>> diff --git a/drivers/net/Makefile b/drivers/net/Makefile
> >>> index 30991834ec..6e0a68834d 100644
> >>> --- a/drivers/net/Makefile
> >>> +++ b/drivers/net/Makefile
> >>> @@ -8,6 +8,7 @@ obj-$(CONFIG_AG7XXX) += ag7xxx.o
> >>>  obj-$(CONFIG_ARMADA100_FEC) += armada100_fec.o
> >>>  obj-$(CONFIG_BCM6348_ETH) += bcm6348-eth.o
> >>>  obj-$(CONFIG_BCM6368_ETH) += bcm6368-eth.o
> >>> +obj-$(CONFIG_BCMGENET) += bcmgenet.o
> >>>  obj-$(CONFIG_DRIVER_AT91EMAC) += at91_emac.o
> >>>  obj-$(CONFIG_DRIVER_AX88180) += ax88180.o
> >>>  obj-$(CONFIG_BCM_SF2_ETH) += bcm-sf2-eth.o
> >>> diff --git a/drivers/net/bcmgenet.c b/drivers/net/bcmgenet.c
> >>> new file mode 100644
> >>> index 0000000000..4f8f190071
> >>> --- /dev/null
> >>> +++ b/drivers/net/bcmgenet.c
> >>> @@ -0,0 +1,722 @@
> >>> +// SPDX-License-Identifier: GPL-2.0+
> >>> +/*
> >>> + * Copyright (C) 2019 Amit Singh Tomar <amittomer25 at gmail.com>
> >>> + *
> >>> + * Driver for Broadcom GENETv5 Ethernet controller (as found on the RPi4)
> >>> + * This driver is based on the Linux driver:
> >>> + *      drivers/net/ethernet/broadcom/genet/bcmgenet.c
> >>> + *      which is: Copyright (c) 2014-2017 Broadcom
> >>> + *
> >>> + * The hardware supports multiple queues (16 priority queues and one
> >>> + * default queue), both for RX and TX. There are 256 DMA descriptors (both
> >>> + * for TX and RX), and they live in MMIO registers. The hardware allows
> >>> + * assigning descriptor ranges to queues, but we choose the most simple setup:
> >>> + * All 256 descriptors are assigned to the default queue (#16).
> >>> + * Also the Linux driver supports multiple generations of the MAC, whereas
> >>> + * we only support v5, as used in the Raspberry Pi 4.
> >>> + */
> >>> +
> >>> +#include <asm/io.h>
> >>> +#include <clk.h>
> >>> +#include <cpu_func.h>
> >>> +#include <dm.h>
> >>> +#include <fdt_support.h>
> >>> +#include <linux/err.h>
> >>> +#include <malloc.h>
> >>> +#include <miiphy.h>
> >>> +#include <net.h>
> >>> +#include <dm/of_access.h>
> >>> +#include <dm/ofnode.h>
> >>> +#include <linux/iopoll.h>
> >>> +#include <linux/sizes.h>
> >>> +#include <asm/dma-mapping.h>
> >>> +#include <wait_bit.h>
> >>> +
> >>> +/* Register definitions derived from Linux source */
> >>> +#define SYS_REV_CTRL			0x00
> >>> +
> >>> +#define SYS_PORT_CTRL			0x04
> >>> +#define PORT_MODE_EXT_GPHY		3
> >>> +
> >>> +#define GENET_SYS_OFF			0x0000
> >>> +#define SYS_RBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x08)
> >>> +#define SYS_TBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x0c)
> >>> +
> >>> +#define GENET_EXT_OFF			0x0080
> >>> +#define EXT_RGMII_OOB_CTRL		(GENET_EXT_OFF + 0x0c)
> >>> +#define RGMII_LINK			BIT(4)
> >>> +#define OOB_DISABLE			BIT(5)
> >>> +#define RGMII_MODE_EN			BIT(6)
> >>> +#define ID_MODE_DIS			BIT(16)
> >>> +
> >>> +#define GENET_RBUF_OFF			0x0300
> >>> +#define RBUF_TBUF_SIZE_CTRL		(GENET_RBUF_OFF + 0xb4)
> >>> +#define RBUF_CTRL			(GENET_RBUF_OFF + 0x00)
> >>> +#define RBUF_ALIGN_2B			BIT(1)
> >>> +
> >>> +#define GENET_UMAC_OFF			0x0800
> >>> +#define UMAC_MIB_CTRL			(GENET_UMAC_OFF + 0x580)
> >>> +#define UMAC_MAX_FRAME_LEN		(GENET_UMAC_OFF + 0x014)
> >>> +#define UMAC_MAC0			(GENET_UMAC_OFF + 0x00c)
> >>> +#define UMAC_MAC1			(GENET_UMAC_OFF + 0x010)
> >>> +#define UMAC_CMD			(GENET_UMAC_OFF + 0x008)
> >>> +#define MDIO_CMD			(GENET_UMAC_OFF + 0x614)
> >>> +#define UMAC_TX_FLUSH			(GENET_UMAC_OFF + 0x334)
> >>> +#define MDIO_START_BUSY			BIT(29)
> >>> +#define MDIO_READ_FAIL			BIT(28)
> >>> +#define MDIO_RD				(2 << 26)
> >>> +#define MDIO_WR				BIT(26)
> >>> +#define MDIO_PMD_SHIFT			21
> >>> +#define MDIO_PMD_MASK			0x1f
> >>> +#define MDIO_REG_SHIFT			16
> >>> +#define MDIO_REG_MASK			0x1f
> >>> +
> >>> +#define CMD_TX_EN			BIT(0)
> >>> +#define CMD_RX_EN			BIT(1)
> >>> +#define UMAC_SPEED_10			0
> >>> +#define UMAC_SPEED_100			1
> >>> +#define UMAC_SPEED_1000			2
> >>> +#define UMAC_SPEED_2500			3
> >>> +#define CMD_SPEED_SHIFT			2
> >>> +#define CMD_SPEED_MASK			3
> >>> +#define CMD_SW_RESET			BIT(13)
> >>> +#define CMD_LCL_LOOP_EN			BIT(15)
> >>> +#define CMD_TX_EN			BIT(0)
> >>> +#define CMD_RX_EN			BIT(1)
> >>> +
> >>> +#define MIB_RESET_RX			BIT(0)
> >>> +#define MIB_RESET_RUNT			BIT(1)
> >>> +#define MIB_RESET_TX			BIT(2)
> >>> +
> >>> +/* total number of Buffer Descriptors, same for Rx/Tx */
> >>> +#define TOTAL_DESCS			256
> >>> +#define RX_DESCS			TOTAL_DESCS
> >>> +#define TX_DESCS			TOTAL_DESCS
> >>> +
> >>> +#define DEFAULT_Q			0x10
> >>> +
> >>> +/* Body(1500) + EH_SIZE(14) + VLANTAG(4) + BRCMTAG(6) + FCS(4) = 1528.
> >>> + * 1536 is multiple of 256 bytes
> >>> + */
> >>> +#define ENET_BRCM_TAG_LEN		6
> >>> +#define ENET_PAD			8
> >>> +#define ENET_MAX_MTU_SIZE		(ETH_DATA_LEN + ETH_HLEN +	 \
> >>> +					 VLAN_HLEN + ENET_BRCM_TAG_LEN + \
> >>> +					 ETH_FCS_LEN + ENET_PAD)
> >>> +
> >>> +/* Tx/Rx Dma Descriptor common bits */
> >>> +#define DMA_EN				BIT(0)
> >>> +#define DMA_RING_BUF_EN_SHIFT		0x01
> >>> +#define DMA_RING_BUF_EN_MASK		0xffff
> >>> +#define DMA_BUFLENGTH_MASK		0x0fff
> >>> +#define DMA_BUFLENGTH_SHIFT		16
> >>> +#define DMA_RING_SIZE_SHIFT		16
> >>> +#define DMA_OWN				0x8000
> >>> +#define DMA_EOP				0x4000
> >>> +#define DMA_SOP				0x2000
> >>> +#define DMA_WRAP			0x1000
> >>> +#define DMA_MAX_BURST_LENGTH		0x8
> >>> +/* Tx specific DMA descriptor bits */
> >>> +#define DMA_TX_UNDERRUN			0x0200
> >>> +#define DMA_TX_APPEND_CRC		0x0040
> >>> +#define DMA_TX_OW_CRC			0x0020
> >>> +#define DMA_TX_DO_CSUM			0x0010
> >>> +#define DMA_TX_QTAG_SHIFT		7
> >>> +
> >>> +/* DMA rings size */
> >>> +#define DMA_RING_SIZE			0x40
> >>> +#define DMA_RINGS_SIZE			(DMA_RING_SIZE * (DEFAULT_Q + 1))
> >>> +
> >>> +/* DMA descriptor */
> >>> +#define DMA_DESC_LENGTH_STATUS		0x00
> >>> +#define DMA_DESC_ADDRESS_LO		0x04
> >>> +#define DMA_DESC_ADDRESS_HI		0x08
> >>> +#define DMA_DESC_SIZE			12
> >>> +
> >>> +#define GENET_RX_OFF			0x2000
> >>> +#define GENET_RDMA_REG_OFF					\
> >>> +	(GENET_RX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> >>> +#define GENET_TX_OFF			0x4000
> >>> +#define GENET_TDMA_REG_OFF					\
> >>> +	(GENET_TX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
> >>> +
> >>> +#define DMA_FC_THRESH_HI		(RX_DESCS >> 4)
> >>> +#define DMA_FC_THRESH_LO		5
> >>> +#define DMA_FC_THRESH_VALUE		((DMA_FC_THRESH_LO << 16) |	\
> >>> +					  DMA_FC_THRESH_HI)
> >>> +
> >>> +#define DMA_XOFF_THRESHOLD_SHIFT	16
> >>> +
> >>> +#define TDMA_RING_REG_BASE					\
> >>> +	(GENET_TDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> >>> +#define TDMA_READ_PTR			(TDMA_RING_REG_BASE + 0x00)
> >>> +#define TDMA_CONS_INDEX			(TDMA_RING_REG_BASE + 0x08)
> >>> +#define TDMA_PROD_INDEX			(TDMA_RING_REG_BASE + 0x0c)
> >>> +#define DMA_RING_BUF_SIZE		0x10
> >>> +#define DMA_START_ADDR			0x14
> >>> +#define DMA_END_ADDR			0x1c
> >>> +#define DMA_MBUF_DONE_THRESH		0x24
> >>> +#define TDMA_FLOW_PERIOD		(TDMA_RING_REG_BASE + 0x28)
> >>> +#define TDMA_WRITE_PTR			(TDMA_RING_REG_BASE + 0x2c)
> >>> +
> >>> +#define RDMA_RING_REG_BASE					\
> >>> +	(GENET_RDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
> >>> +#define RDMA_WRITE_PTR			(RDMA_RING_REG_BASE + 0x00)
> >>> +#define RDMA_PROD_INDEX			(RDMA_RING_REG_BASE + 0x08)
> >>> +#define RDMA_CONS_INDEX			(RDMA_RING_REG_BASE + 0x0c)
> >>> +#define RDMA_XON_XOFF_THRESH		(RDMA_RING_REG_BASE + 0x28)
> >>> +#define RDMA_READ_PTR			(RDMA_RING_REG_BASE + 0x2c)
> >>> +
> >>> +#define TDMA_REG_BASE			(GENET_TDMA_REG_OFF + DMA_RINGS_SIZE)
> >>> +#define RDMA_REG_BASE			(GENET_RDMA_REG_OFF + DMA_RINGS_SIZE)
> >>> +#define DMA_RING_CFG			0x00
> >>> +#define DMA_CTRL			0x04
> >>> +#define DMA_SCB_BURST_SIZE		0x0c
> >>> +
> >>> +#define RX_BUF_LENGTH			2048
> >>> +#define RX_TOTAL_BUFSIZE		(RX_BUF_LENGTH * RX_DESCS)
> >>> +#define RX_BUF_OFFSET			2
> >>> +
> >>> +struct bcmgenet_eth_priv {
> >>> +	char rxbuffer[RX_TOTAL_BUFSIZE] __aligned(ARCH_DMA_MINALIGN);
> >>> +	void *mac_reg;
> >>> +	void *tx_desc_base;
> >>> +	void *rx_desc_base;
> >>> +	int tx_index;
> >>> +	int rx_index;
> >>> +	int c_index;
> >>> +	int phyaddr;
> >>> +	u32 interface;
> >>> +	u32 speed;
> >>> +	struct phy_device *phydev;
> >>> +	struct mii_dev *bus;
> >>> +};
> >>> +
> >>> +static void bcmgenet_umac_reset(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	u32 reg;
> >>> +
> >>> +	reg = readl(priv->mac_reg + SYS_RBUF_FLUSH_CTRL);
> >>> +	reg |= BIT(1);
> >>> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> >>> +	udelay(10);
> >>> +
> >>> +	reg &= ~BIT(1);
> >>> +	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> >>> +	udelay(10);
> >>> +
> >>> +	writel(0, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
> >>> +	udelay(10);
> >>> +
> >>> +	writel(0, priv->mac_reg + UMAC_CMD);
> >>> +
> >>> +	writel(CMD_SW_RESET | CMD_LCL_LOOP_EN, priv->mac_reg + UMAC_CMD);
> >>> +	udelay(2);
> >>> +	writel(0, priv->mac_reg + UMAC_CMD);
> >>> +
> >>> +	/* clear tx/rx counter */
> >>> +	writel(MIB_RESET_RX | MIB_RESET_TX | MIB_RESET_RUNT,
> >>> +	       priv->mac_reg + UMAC_MIB_CTRL);
> >>> +	writel(0, priv->mac_reg + UMAC_MIB_CTRL);
> >>> +
> >>> +	writel(ENET_MAX_MTU_SIZE, priv->mac_reg + UMAC_MAX_FRAME_LEN);
> >>> +
> >>> +	/* init rx registers, enable ip header optimization */
> >>> +	reg = readl(priv->mac_reg + RBUF_CTRL);
> >>> +	reg |= RBUF_ALIGN_2B;
> >>> +	writel(reg, (priv->mac_reg + RBUF_CTRL));
> >>> +
> >>> +	writel(1, (priv->mac_reg + RBUF_TBUF_SIZE_CTRL));
> >>> +}
> >>> +
> >>> +static int bcmgenet_gmac_write_hwaddr(struct udevice *dev)
> >>> +{
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> >>> +	uchar *addr = pdata->enetaddr;
> >>> +	u32 reg;
> >>> +
> >>> +	reg = addr[0] << 24 | addr[1] << 16 | addr[2] << 8 | addr[3];
> >>> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC0);
> >>> +
> >>> +	reg = addr[4] << 8 | addr[5];
> >>> +	writel_relaxed(reg, priv->mac_reg + UMAC_MAC1);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static void bcmgenet_disable_dma(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL, DMA_EN);
> >>> +	clrbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, DMA_EN);
> >>> +
> >>> +	writel(1, priv->mac_reg + UMAC_TX_FLUSH);
> >>> +	udelay(10);
> >>> +	writel(0, priv->mac_reg + UMAC_TX_FLUSH);
> >>> +}
> >>> +
> >>> +static void bcmgenet_enable_dma(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	u32 dma_ctrl = (1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT)) | DMA_EN;
> >>> +
> >>> +	writel(dma_ctrl, priv->mac_reg + TDMA_REG_BASE + DMA_CTRL);
> >>> +
> >>> +	setbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, dma_ctrl);
> >>> +}
> >>> +
> >>> +static int bcmgenet_gmac_eth_send(struct udevice *dev, void *packet, int length)
> >>> +{
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	void *desc_base = priv->tx_desc_base + priv->tx_index * DMA_DESC_SIZE;
> >>> +	u32 len_stat = length << DMA_BUFLENGTH_SHIFT;
> >>> +	ulong packet_aligned = rounddown((ulong)packet, ARCH_DMA_MINALIGN);
> >>> +	u32 prod_index, cons;
> >>> +	u32 tries = 100;
> >>> +
> >>> +	prod_index = readl(priv->mac_reg + TDMA_PROD_INDEX);
> >>> +
> >>> +	/* There is actually no reason for the rounding here, but the ARMv7
> >>> +	 * implementation of flush_dcache_range() checks for aligned
> >>> +	 * boundaries of the flushed range.
> >>> +	 * Adjust them here to pass that check and avoid misleading messages.
> >>> +	 */
> >>> +	flush_dcache_range(packet_aligned,
> >>> +			   packet_aligned + roundup(length, ARCH_DMA_MINALIGN));
> >>> +
> >>> +	len_stat |= 0x3F << DMA_TX_QTAG_SHIFT;
> >>> +	len_stat |= DMA_TX_APPEND_CRC | DMA_SOP | DMA_EOP;
> >>> +
> >>> +	/* Set-up packet for transmission */
> >>> +	writel(lower_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_LO));
> >>> +	writel(upper_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_HI));
> >>> +	writel(len_stat, (desc_base + DMA_DESC_LENGTH_STATUS));
> >>> +
> >>> +	/* Increment index and start transmission */
> >>> +	if (++priv->tx_index >= TX_DESCS)
> >>> +		priv->tx_index = 0;
> >>> +
> >>> +	prod_index++;
> >>> +
> >>> +	/* Start Transmisson */
> >>> +	writel(prod_index, priv->mac_reg + TDMA_PROD_INDEX);
> >>> +
> >>> +	do {
> >>> +		cons = readl(priv->mac_reg + TDMA_CONS_INDEX);
> >>> +	} while ((cons & 0xffff) < prod_index && --tries);
> >>> +	if (!tries)
> >>> +		return -ETIMEDOUT;
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +/* Check whether all cache lines affected by an invalidate are within
> >>> + * the buffer, to make sure we don't accidentally lose unrelated dirty
> >>> + * data stored nearby.
> >>> + * Alignment of the buffer start address will be checked in the implementation
> >>> + * of invalidate_dcache_range().
> >>> + */
> >>> +static void invalidate_dcache_check(unsigned long addr, size_t size,
> >>> +				    size_t buffer_size)
> >>> +{
> >>> +	size_t inval_size = roundup(size, ARCH_DMA_MINALIGN);
> >>> +
> >>> +	if (unlikely(inval_size > buffer_size))
> >>> +		printf("WARNING: Cache invalidate area exceeds buffer size\n");
> >>> +
> >>> +	invalidate_dcache_range(addr, addr + inval_size);
> >>> +}
> >>> +
> >>> +static int bcmgenet_gmac_eth_recv(struct udevice *dev,
> >>> +				  int flags, uchar **packetp)
> >>> +{
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	void *desc_base = priv->rx_desc_base + priv->rx_index * DMA_DESC_SIZE;
> >>> +	u32 prod_index = readl(priv->mac_reg + RDMA_PROD_INDEX);
> >>> +	u32 length, addr;
> >>> +
> >>> +	if (prod_index == priv->c_index)
> >>> +		return -EAGAIN;
> >>> +
> >>> +	length = readl(desc_base + DMA_DESC_LENGTH_STATUS);
> >>> +	length = (length >> DMA_BUFLENGTH_SHIFT) & DMA_BUFLENGTH_MASK;
> >>> +	addr = readl(desc_base + DMA_DESC_ADDRESS_LO);
> >>> +
> >>> +	invalidate_dcache_check(addr, length, RX_BUF_LENGTH);
> >>> +
> >>> +	/* To cater for the IP header alignment the hardware does.
> >>> +	 * This would actually not be needed if we don't program
> >>> +	 * RBUF_ALIGN_2B
> >>> +	 */
> >>> +	*packetp = (uchar *)(ulong)addr + RX_BUF_OFFSET;
> >>> +
> >>> +	return length - RX_BUF_OFFSET;
> >>> +}
> >>> +
> >>> +static int bcmgenet_gmac_free_pkt(struct udevice *dev, uchar *packet,
> >>> +				  int length)
> >>> +{
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +
> >>> +	/* Tell the MAC we have consumed that last receive buffer. */
> >>> +	priv->c_index = (priv->c_index + 1) & 0xFFFF;
> >>> +	writel(priv->c_index, priv->mac_reg + RDMA_CONS_INDEX);
> >>> +
> >>> +	/* Forward our descriptor pointer, wrapping around if needed. */
> >>> +	if (++priv->rx_index >= RX_DESCS)
> >>> +		priv->rx_index = 0;
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static void rx_descs_init(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	char *rxbuffs = &priv->rxbuffer[0];
> >>> +	u32 len_stat, i;
> >>> +	void *desc_base = priv->rx_desc_base;
> >>> +
> >>> +	priv->c_index = 0;
> >>> +
> >>> +	len_stat = (RX_BUF_LENGTH << DMA_BUFLENGTH_SHIFT) | DMA_OWN;
> >>> +
> >>> +	for (i = 0; i < RX_DESCS; i++) {
> >>> +		writel(lower_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> >>> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_LO);
> >>> +		writel(upper_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
> >>> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_HI);
> >>> +		writel(len_stat,
> >>> +		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_LENGTH_STATUS);
> >>> +	}
> >>> +}
> >>> +
> >>> +static void rx_ring_init(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	writel(DMA_MAX_BURST_LENGTH,
> >>> +	       priv->mac_reg + RDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> >>> +
> >>> +	writel(0x0, priv->mac_reg + RDMA_RING_REG_BASE + DMA_START_ADDR);
> >>> +	writel(0x0, priv->mac_reg + RDMA_READ_PTR);
> >>> +	writel(0x0, priv->mac_reg + RDMA_WRITE_PTR);
> >>> +	writel(RX_DESCS * DMA_DESC_SIZE / 4 - 1,
> >>> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_END_ADDR);
> >>> +
> >>> +	writel(0x0, priv->mac_reg + RDMA_PROD_INDEX);
> >>> +	writel(0x0, priv->mac_reg + RDMA_CONS_INDEX);
> >>> +	writel((RX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> >>> +	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> >>> +	writel(DMA_FC_THRESH_VALUE, priv->mac_reg + RDMA_XON_XOFF_THRESH);
> >>> +	writel(1 << DEFAULT_Q, priv->mac_reg + RDMA_REG_BASE + DMA_RING_CFG);
> >>> +}
> >>> +
> >>> +static void tx_ring_init(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	writel(DMA_MAX_BURST_LENGTH,
> >>> +	       priv->mac_reg + TDMA_REG_BASE + DMA_SCB_BURST_SIZE);
> >>> +
> >>> +	writel(0x0, priv->mac_reg + TDMA_RING_REG_BASE + DMA_START_ADDR);
> >>> +	writel(0x0, priv->mac_reg + TDMA_READ_PTR);
> >>> +	writel(0x0, priv->mac_reg + TDMA_WRITE_PTR);
> >>> +	writel(TX_DESCS * DMA_DESC_SIZE / 4 - 1,
> >>> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_END_ADDR);
> >>> +	writel(0x0, priv->mac_reg + TDMA_PROD_INDEX);
> >>> +	writel(0x0, priv->mac_reg + TDMA_CONS_INDEX);
> >>> +	writel(0x1, priv->mac_reg + TDMA_RING_REG_BASE + DMA_MBUF_DONE_THRESH);
> >>> +	writel(0x0, priv->mac_reg + TDMA_FLOW_PERIOD);
> >>> +	writel((TX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
> >>> +	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
> >>> +
> >>> +	writel(1 << DEFAULT_Q, priv->mac_reg + TDMA_REG_BASE + DMA_RING_CFG);
> >>> +}
> >>> +
> >>> +static int bcmgenet_adjust_link(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	struct phy_device *phy_dev = priv->phydev;
> >>> +	u32 speed;
> >>> +
> >>> +	switch (phy_dev->speed) {
> >>> +	case SPEED_1000:
> >>> +		speed = UMAC_SPEED_1000;
> >>> +		break;
> >>> +	case SPEED_100:
> >>> +		speed = UMAC_SPEED_100;
> >>> +		break;
> >>> +	case SPEED_10:
> >>> +		speed = UMAC_SPEED_10;
> >>> +		break;
> >>> +	default:
> >>> +		printf("bcmgenet: Unsupported PHY speed: %d\n", phy_dev->speed);
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	clrsetbits_32(priv->mac_reg + EXT_RGMII_OOB_CTRL, OOB_DISABLE,
> >>> +			RGMII_LINK | RGMII_MODE_EN | ID_MODE_DIS);
> >>> +
> >>> +	writel(speed << CMD_SPEED_SHIFT, (priv->mac_reg + UMAC_CMD));
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int bcmgenet_gmac_eth_start(struct udevice *dev)
> >>> +{
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	int ret;
> >>> +
> >>> +	priv->tx_desc_base = priv->mac_reg + GENET_TX_OFF;
> >>> +	priv->rx_desc_base = priv->mac_reg + GENET_RX_OFF;
> >>> +	priv->tx_index = 0x0;
> >>> +	priv->rx_index = 0x0;
> >>> +
> >>> +	bcmgenet_umac_reset(priv);
> >>> +
> >>> +	bcmgenet_gmac_write_hwaddr(dev);
> >>> +
> >>> +	/* Disable RX/TX DMA and flush TX queues */
> >>> +	bcmgenet_disable_dma(priv);
> >>> +
> >>> +	rx_ring_init(priv);
> >>> +	rx_descs_init(priv);
> >>> +
> >>> +	tx_ring_init(priv);
> >>> +
> >>> +	/* Enable RX/TX DMA */
> >>> +	bcmgenet_enable_dma(priv);
> >>> +
> >>> +	/* read PHY properties over the wire from generic PHY set-up */
> >>> +	ret = phy_startup(priv->phydev);
> >>> +	if (ret) {
> >>> +		printf("bcmgenet: PHY startup failed: %d\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	/* Update MAC registers based on PHY property */
> >>> +	ret = bcmgenet_adjust_link(priv);
> >>> +	if (ret) {
> >>> +		printf("bcmgenet: adjust PHY link failed: %d\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	/* Enable Rx/Tx */
> >>> +	setbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int bcmgenet_phy_init(struct bcmgenet_eth_priv *priv, void *dev)
> >>> +{
> >>> +	struct phy_device *phydev;
> >>> +	int ret;
> >>> +
> >>> +	phydev = phy_connect(priv->bus, priv->phyaddr, dev, priv->interface);
> >>> +	if (!phydev)
> >>> +		return -ENODEV;
> >>> +
> >>> +	phydev->supported &= PHY_GBIT_FEATURES;
> >>> +	if (priv->speed) {
> >>> +		ret = phy_set_supported(priv->phydev, priv->speed);
> >>> +		if (ret)
> >>> +			return ret;
> >>> +	}
> >>> +	phydev->advertising = phydev->supported;
> >>> +
> >>> +	phy_connect_dev(phydev, dev);
> >>> +
> >>> +	priv->phydev = phydev;
> >>> +	phy_config(priv->phydev);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static void bcmgenet_mdio_start(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	setbits_32(priv->mac_reg + MDIO_CMD, MDIO_START_BUSY);
> >>> +}
> >>> +
> >>> +static int bcmgenet_mdio_write(struct mii_dev *bus, int addr, int devad,
> >>> +			       int reg, u16 value)
> >>> +{
> >>> +	struct udevice *dev = bus->priv;
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	u32 val;
> >>> +
> >>> +	/* Prepare the read operation */
> >>> +	val = MDIO_WR | (addr << MDIO_PMD_SHIFT) |
> >>> +		(reg << MDIO_REG_SHIFT) | (0xffff & value);
> >>> +	writel_relaxed(val,  priv->mac_reg + MDIO_CMD);
> >>> +
> >>> +	/* Start MDIO transaction */
> >>> +	bcmgenet_mdio_start(priv);
> >>> +
> >>> +	return wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> >>> +			       MDIO_START_BUSY, false, 20, true);
> >>> +}
> >>> +
> >>> +static int bcmgenet_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
> >>> +{
> >>> +	struct udevice *dev = bus->priv;
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	u32 val;
> >>> +	int ret;
> >>> +
> >>> +	/* Prepare the read operation */
> >>> +	val = MDIO_RD | (addr << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
> >>> +	writel_relaxed(val, priv->mac_reg + MDIO_CMD);
> >>> +
> >>> +	/* Start MDIO transaction */
> >>> +	bcmgenet_mdio_start(priv);
> >>> +
> >>> +	ret = wait_for_bit_32(priv->mac_reg + MDIO_CMD,
> >>> +			      MDIO_START_BUSY, false, 20, true);
> >>> +	if (ret)
> >>> +		return ret;
> >>> +
> >>> +	val = readl_relaxed(priv->mac_reg + MDIO_CMD);
> >>> +
> >>> +	return val & 0xffff;
> >>> +}
> >>> +
> >>> +static int bcmgenet_mdio_init(const char *name, struct udevice *priv)
> >>> +{
> >>> +	struct mii_dev *bus = mdio_alloc();
> >>> +
> >>> +	if (!bus) {
> >>> +		debug("Failed to allocate MDIO bus\n");
> >>> +		return -ENOMEM;
> >>> +	}
> >>> +
> >>> +	bus->read = bcmgenet_mdio_read;
> >>> +	bus->write = bcmgenet_mdio_write;
> >>> +	snprintf(bus->name, sizeof(bus->name), name);
> >>> +	bus->priv = (void *)priv;
> >>> +
> >>> +	return mdio_register(bus);
> >>> +}
> >>> +
> >>> +/* We only support RGMII (as used on the RPi4). */
> >>> +static int bcmgenet_interface_set(struct bcmgenet_eth_priv *priv)
> >>> +{
> >>> +	phy_interface_t phy_mode = priv->interface;
> >>> +
> >>> +	switch (phy_mode) {
> >>> +	case PHY_INTERFACE_MODE_RGMII:
> >>> +	case PHY_INTERFACE_MODE_RGMII_RXID:
> >>> +		writel(PORT_MODE_EXT_GPHY, priv->mac_reg + SYS_PORT_CTRL);
> >>> +		break;
> >>> +	default:
> >>> +		printf("unknown phy mode: %d\n", priv->interface);
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int bcmgenet_eth_probe(struct udevice *dev)
> >>> +{
> >>> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	ofnode mdio_node;
> >>> +	const char *name;
> >>> +	u32 reg;
> >>> +	int ret;
> >>> +	u8 major;
> >>> +
> >>> +	priv->mac_reg = map_physmem(pdata->iobase, SZ_64K, MAP_NOCACHE);
> >>> +	priv->interface = pdata->phy_interface;
> >>> +	priv->speed = pdata->max_speed;
> >>> +
> >>> +	/* Read GENET HW version */
> >>> +	reg = readl_relaxed(priv->mac_reg + SYS_REV_CTRL);
> >>> +	major = (reg >> 24) & 0x0f;
> >>> +	if (major != 6) {
> >>> +		if (major == 5)
> >>> +			major = 4;
> >>> +		else if (major == 0)
> >>> +			major = 1;
> >>> +
> >>> +		printf("Unsupported GENETv%d.%d\n", major, (reg >> 16) & 0x0f);
> >>> +		return -ENODEV;
> >>> +	}
> >>> +
> >>> +	ret = bcmgenet_interface_set(priv);
> >>> +	if (ret)
> >>> +		return ret;
> >>> +
> >>> +	mdio_node = dev_read_first_subnode(dev);
> >>> +	name = ofnode_get_name(mdio_node);
> >>> +
> >>> +	ret = bcmgenet_mdio_init(name, dev);
> >>> +	if (ret)
> >>> +		return ret;
> >>> +
> >>> +	priv->bus = miiphy_get_dev_by_name(name);
> >>> +
> >>> +	return bcmgenet_phy_init(priv, dev);
> >>> +}
> >>> +
> >>> +static void bcmgenet_gmac_eth_stop(struct udevice *dev)
> >>> +{
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +
> >>> +	clrbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
> >>> +	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL,
> >>> +		     1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT) | DMA_EN);
> >>> +}
> >>> +
> >>> +static const struct eth_ops bcmgenet_gmac_eth_ops = {
> >>> +	.start                  = bcmgenet_gmac_eth_start,
> >>> +	.write_hwaddr           = bcmgenet_gmac_write_hwaddr,
> >>> +	.send                   = bcmgenet_gmac_eth_send,
> >>> +	.recv                   = bcmgenet_gmac_eth_recv,
> >>> +	.free_pkt               = bcmgenet_gmac_free_pkt,
> >>> +	.stop                   = bcmgenet_gmac_eth_stop,
> >>> +};
> >>> +
> >>> +static int bcmgenet_eth_ofdata_to_platdata(struct udevice *dev)
> >>> +{
> >>> +	struct eth_pdata *pdata = dev_get_platdata(dev);
> >>> +	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
> >>> +	struct ofnode_phandle_args phy_node;
> >>> +	const char *phy_mode;
> >>> +	int ret;
> >>> +
> >>> +	pdata->iobase = dev_read_addr(dev);    
> >>
> >> I suggest to change the type of pdata->iobase to void __iomem * and use
> >> dev_remap_addr(). This saves you the manual map_physmem() in
> >> bcmgenet_eth_probe(). Also dev_remap_addr() uses the correct register
> >> size from DT instead of the hard-coded SZ_64K.  
> > 
> > I see your point, but was wondering about the separation between ofdata_to_platdata and the probe routine. The former is just supposed to collect all the data, the latter to actually instantiate the device. So reading the address from the DT is separate from mapping the region.
> > 
> > Anyway I guess it's not a showstopper that I want to respin the series for, so could you send a follow-up patch? Then we could have the discussion there.
> >   
> 
> It's not for me :D
> 
> AFAIK ofdata_to_platdata is optional and is only required if you
> additionally need to support driver configuration without device-tree
> (e.g. in a size-constained SPL). Usually you could put everything in the
> probe function.
> 
> >   
> >>  
> >>> +
> >>> +	/* Get phy mode from DT */
> >>> +	pdata->phy_interface = -1;
> >>> +	phy_mode = dev_read_string(dev, "phy-mode");
> >>> +	if (phy_mode)
> >>> +		pdata->phy_interface = phy_get_interface_by_name(phy_mode);
> >>> +	if (pdata->phy_interface == -1) {
> >>> +		debug("%s: Invalid PHY interface '%s'\n", __func__, phy_mode);
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
> >>> +					 &phy_node);
> >>> +	if (!ret) {
> >>> +		ofnode_read_s32(phy_node.node, "reg", &priv->phyaddr);
> >>> +		ofnode_read_s32(phy_node.node, "max-speed", &pdata->max_speed);
> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +/* The BCM2711 implementation has a limited burst length compared to a generic
> >>> + * GENETv5 version, but we go with that shorter value (8) in both cases, for
> >>> + * the sake of simplicity.
> >>> + */
> >>> +static const struct udevice_id bcmgenet_eth_ids[] = {
> >>> +	{.compatible = "brcm,genet-v5"},
> >>> +	{.compatible = "brcm,bcm2711-genet-v5"},
> >>> +	{}
> >>> +};
> >>> +
> >>> +U_BOOT_DRIVER(eth_bcmgenet) = {
> >>> +	.name   = "eth_bcmgenet",
> >>> +	.id     = UCLASS_ETH,
> >>> +	.of_match = bcmgenet_eth_ids,
> >>> +	.ofdata_to_platdata = bcmgenet_eth_ofdata_to_platdata,
> >>> +	.probe  = bcmgenet_eth_probe,
> >>> +	.ops    = &bcmgenet_gmac_eth_ops,
> >>> +	.priv_auto_alloc_size = sizeof(struct bcmgenet_eth_priv),
> >>> +	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
> >>> +	.flags = DM_FLAG_ALLOC_PRIV_DMA,
> >>> +};
> >>>     
> >>  
> >   
>

Patch

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 01d087f229..4d1013c984 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -136,6 +136,13 @@  config BCM6368_ETH
 	help
 	  This driver supports the BCM6368 Ethernet MAC.
 
+config BCMGENET
+	bool "BCMGENET V5 support"
+	depends on DM_ETH
+	select PHYLIB
+	help
+	  This driver supports the BCMGENET Ethernet MAC.
+
 config DWC_ETH_QOS
 	bool "Synopsys DWC Ethernet QOS device support"
 	depends on DM_ETH
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 30991834ec..6e0a68834d 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -8,6 +8,7 @@  obj-$(CONFIG_AG7XXX) += ag7xxx.o
 obj-$(CONFIG_ARMADA100_FEC) += armada100_fec.o
 obj-$(CONFIG_BCM6348_ETH) += bcm6348-eth.o
 obj-$(CONFIG_BCM6368_ETH) += bcm6368-eth.o
+obj-$(CONFIG_BCMGENET) += bcmgenet.o
 obj-$(CONFIG_DRIVER_AT91EMAC) += at91_emac.o
 obj-$(CONFIG_DRIVER_AX88180) += ax88180.o
 obj-$(CONFIG_BCM_SF2_ETH) += bcm-sf2-eth.o
diff --git a/drivers/net/bcmgenet.c b/drivers/net/bcmgenet.c
new file mode 100644
index 0000000000..4f8f190071
--- /dev/null
+++ b/drivers/net/bcmgenet.c
@@ -0,0 +1,722 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Amit Singh Tomar <amittomer25 at gmail.com>
+ *
+ * Driver for Broadcom GENETv5 Ethernet controller (as found on the RPi4)
+ * This driver is based on the Linux driver:
+ *      drivers/net/ethernet/broadcom/genet/bcmgenet.c
+ *      which is: Copyright (c) 2014-2017 Broadcom
+ *
+ * The hardware supports multiple queues (16 priority queues and one
+ * default queue), both for RX and TX. There are 256 DMA descriptors (both
+ * for TX and RX), and they live in MMIO registers. The hardware allows
+ * assigning descriptor ranges to queues, but we choose the most simple setup:
+ * All 256 descriptors are assigned to the default queue (#16).
+ * Also the Linux driver supports multiple generations of the MAC, whereas
+ * we only support v5, as used in the Raspberry Pi 4.
+ */
+
+#include <asm/io.h>
+#include <clk.h>
+#include <cpu_func.h>
+#include <dm.h>
+#include <fdt_support.h>
+#include <linux/err.h>
+#include <malloc.h>
+#include <miiphy.h>
+#include <net.h>
+#include <dm/of_access.h>
+#include <dm/ofnode.h>
+#include <linux/iopoll.h>
+#include <linux/sizes.h>
+#include <asm/dma-mapping.h>
+#include <wait_bit.h>
+
+/* Register definitions derived from Linux source */
+#define SYS_REV_CTRL			0x00
+
+#define SYS_PORT_CTRL			0x04
+#define PORT_MODE_EXT_GPHY		3
+
+#define GENET_SYS_OFF			0x0000
+#define SYS_RBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x08)
+#define SYS_TBUF_FLUSH_CTRL		(GENET_SYS_OFF  + 0x0c)
+
+#define GENET_EXT_OFF			0x0080
+#define EXT_RGMII_OOB_CTRL		(GENET_EXT_OFF + 0x0c)
+#define RGMII_LINK			BIT(4)
+#define OOB_DISABLE			BIT(5)
+#define RGMII_MODE_EN			BIT(6)
+#define ID_MODE_DIS			BIT(16)
+
+#define GENET_RBUF_OFF			0x0300
+#define RBUF_TBUF_SIZE_CTRL		(GENET_RBUF_OFF + 0xb4)
+#define RBUF_CTRL			(GENET_RBUF_OFF + 0x00)
+#define RBUF_ALIGN_2B			BIT(1)
+
+#define GENET_UMAC_OFF			0x0800
+#define UMAC_MIB_CTRL			(GENET_UMAC_OFF + 0x580)
+#define UMAC_MAX_FRAME_LEN		(GENET_UMAC_OFF + 0x014)
+#define UMAC_MAC0			(GENET_UMAC_OFF + 0x00c)
+#define UMAC_MAC1			(GENET_UMAC_OFF + 0x010)
+#define UMAC_CMD			(GENET_UMAC_OFF + 0x008)
+#define MDIO_CMD			(GENET_UMAC_OFF + 0x614)
+#define UMAC_TX_FLUSH			(GENET_UMAC_OFF + 0x334)
+#define MDIO_START_BUSY			BIT(29)
+#define MDIO_READ_FAIL			BIT(28)
+#define MDIO_RD				(2 << 26)
+#define MDIO_WR				BIT(26)
+#define MDIO_PMD_SHIFT			21
+#define MDIO_PMD_MASK			0x1f
+#define MDIO_REG_SHIFT			16
+#define MDIO_REG_MASK			0x1f
+
+#define CMD_TX_EN			BIT(0)
+#define CMD_RX_EN			BIT(1)
+#define UMAC_SPEED_10			0
+#define UMAC_SPEED_100			1
+#define UMAC_SPEED_1000			2
+#define UMAC_SPEED_2500			3
+#define CMD_SPEED_SHIFT			2
+#define CMD_SPEED_MASK			3
+#define CMD_SW_RESET			BIT(13)
+#define CMD_LCL_LOOP_EN			BIT(15)
+#define CMD_TX_EN			BIT(0)
+#define CMD_RX_EN			BIT(1)
+
+#define MIB_RESET_RX			BIT(0)
+#define MIB_RESET_RUNT			BIT(1)
+#define MIB_RESET_TX			BIT(2)
+
+/* total number of Buffer Descriptors, same for Rx/Tx */
+#define TOTAL_DESCS			256
+#define RX_DESCS			TOTAL_DESCS
+#define TX_DESCS			TOTAL_DESCS
+
+#define DEFAULT_Q			0x10
+
+/* Body(1500) + EH_SIZE(14) + VLANTAG(4) + BRCMTAG(6) + FCS(4) = 1528.
+ * 1536 is multiple of 256 bytes
+ */
+#define ENET_BRCM_TAG_LEN		6
+#define ENET_PAD			8
+#define ENET_MAX_MTU_SIZE		(ETH_DATA_LEN + ETH_HLEN +	 \
+					 VLAN_HLEN + ENET_BRCM_TAG_LEN + \
+					 ETH_FCS_LEN + ENET_PAD)
+
+/* Tx/Rx Dma Descriptor common bits */
+#define DMA_EN				BIT(0)
+#define DMA_RING_BUF_EN_SHIFT		0x01
+#define DMA_RING_BUF_EN_MASK		0xffff
+#define DMA_BUFLENGTH_MASK		0x0fff
+#define DMA_BUFLENGTH_SHIFT		16
+#define DMA_RING_SIZE_SHIFT		16
+#define DMA_OWN				0x8000
+#define DMA_EOP				0x4000
+#define DMA_SOP				0x2000
+#define DMA_WRAP			0x1000
+#define DMA_MAX_BURST_LENGTH		0x8
+/* Tx specific DMA descriptor bits */
+#define DMA_TX_UNDERRUN			0x0200
+#define DMA_TX_APPEND_CRC		0x0040
+#define DMA_TX_OW_CRC			0x0020
+#define DMA_TX_DO_CSUM			0x0010
+#define DMA_TX_QTAG_SHIFT		7
+
+/* DMA rings size */
+#define DMA_RING_SIZE			0x40
+#define DMA_RINGS_SIZE			(DMA_RING_SIZE * (DEFAULT_Q + 1))
+
+/* DMA descriptor */
+#define DMA_DESC_LENGTH_STATUS		0x00
+#define DMA_DESC_ADDRESS_LO		0x04
+#define DMA_DESC_ADDRESS_HI		0x08
+#define DMA_DESC_SIZE			12
+
+#define GENET_RX_OFF			0x2000
+#define GENET_RDMA_REG_OFF					\
+	(GENET_RX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
+#define GENET_TX_OFF			0x4000
+#define GENET_TDMA_REG_OFF					\
+	(GENET_TX_OFF + TOTAL_DESCS * DMA_DESC_SIZE)
+
+#define DMA_FC_THRESH_HI		(RX_DESCS >> 4)
+#define DMA_FC_THRESH_LO		5
+#define DMA_FC_THRESH_VALUE		((DMA_FC_THRESH_LO << 16) |	\
+					  DMA_FC_THRESH_HI)
+
+#define DMA_XOFF_THRESHOLD_SHIFT	16
+
+#define TDMA_RING_REG_BASE					\
+	(GENET_TDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
+#define TDMA_READ_PTR			(TDMA_RING_REG_BASE + 0x00)
+#define TDMA_CONS_INDEX			(TDMA_RING_REG_BASE + 0x08)
+#define TDMA_PROD_INDEX			(TDMA_RING_REG_BASE + 0x0c)
+#define DMA_RING_BUF_SIZE		0x10
+#define DMA_START_ADDR			0x14
+#define DMA_END_ADDR			0x1c
+#define DMA_MBUF_DONE_THRESH		0x24
+#define TDMA_FLOW_PERIOD		(TDMA_RING_REG_BASE + 0x28)
+#define TDMA_WRITE_PTR			(TDMA_RING_REG_BASE + 0x2c)
+
+#define RDMA_RING_REG_BASE					\
+	(GENET_RDMA_REG_OFF + DEFAULT_Q * DMA_RING_SIZE)
+#define RDMA_WRITE_PTR			(RDMA_RING_REG_BASE + 0x00)
+#define RDMA_PROD_INDEX			(RDMA_RING_REG_BASE + 0x08)
+#define RDMA_CONS_INDEX			(RDMA_RING_REG_BASE + 0x0c)
+#define RDMA_XON_XOFF_THRESH		(RDMA_RING_REG_BASE + 0x28)
+#define RDMA_READ_PTR			(RDMA_RING_REG_BASE + 0x2c)
+
+#define TDMA_REG_BASE			(GENET_TDMA_REG_OFF + DMA_RINGS_SIZE)
+#define RDMA_REG_BASE			(GENET_RDMA_REG_OFF + DMA_RINGS_SIZE)
+#define DMA_RING_CFG			0x00
+#define DMA_CTRL			0x04
+#define DMA_SCB_BURST_SIZE		0x0c
+
+#define RX_BUF_LENGTH			2048
+#define RX_TOTAL_BUFSIZE		(RX_BUF_LENGTH * RX_DESCS)
+#define RX_BUF_OFFSET			2
+
+struct bcmgenet_eth_priv {
+	char rxbuffer[RX_TOTAL_BUFSIZE] __aligned(ARCH_DMA_MINALIGN);
+	void *mac_reg;
+	void *tx_desc_base;
+	void *rx_desc_base;
+	int tx_index;
+	int rx_index;
+	int c_index;
+	int phyaddr;
+	u32 interface;
+	u32 speed;
+	struct phy_device *phydev;
+	struct mii_dev *bus;
+};
+
+static void bcmgenet_umac_reset(struct bcmgenet_eth_priv *priv)
+{
+	u32 reg;
+
+	reg = readl(priv->mac_reg + SYS_RBUF_FLUSH_CTRL);
+	reg |= BIT(1);
+	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
+	udelay(10);
+
+	reg &= ~BIT(1);
+	writel(reg, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
+	udelay(10);
+
+	writel(0, (priv->mac_reg + SYS_RBUF_FLUSH_CTRL));
+	udelay(10);
+
+	writel(0, priv->mac_reg + UMAC_CMD);
+
+	writel(CMD_SW_RESET | CMD_LCL_LOOP_EN, priv->mac_reg + UMAC_CMD);
+	udelay(2);
+	writel(0, priv->mac_reg + UMAC_CMD);
+
+	/* clear tx/rx counter */
+	writel(MIB_RESET_RX | MIB_RESET_TX | MIB_RESET_RUNT,
+	       priv->mac_reg + UMAC_MIB_CTRL);
+	writel(0, priv->mac_reg + UMAC_MIB_CTRL);
+
+	writel(ENET_MAX_MTU_SIZE, priv->mac_reg + UMAC_MAX_FRAME_LEN);
+
+	/* init rx registers, enable ip header optimization */
+	reg = readl(priv->mac_reg + RBUF_CTRL);
+	reg |= RBUF_ALIGN_2B;
+	writel(reg, (priv->mac_reg + RBUF_CTRL));
+
+	writel(1, (priv->mac_reg + RBUF_TBUF_SIZE_CTRL));
+}
+
+static int bcmgenet_gmac_write_hwaddr(struct udevice *dev)
+{
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	struct eth_pdata *pdata = dev_get_platdata(dev);
+	uchar *addr = pdata->enetaddr;
+	u32 reg;
+
+	reg = addr[0] << 24 | addr[1] << 16 | addr[2] << 8 | addr[3];
+	writel_relaxed(reg, priv->mac_reg + UMAC_MAC0);
+
+	reg = addr[4] << 8 | addr[5];
+	writel_relaxed(reg, priv->mac_reg + UMAC_MAC1);
+
+	return 0;
+}
+
+static void bcmgenet_disable_dma(struct bcmgenet_eth_priv *priv)
+{
+	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL, DMA_EN);
+	clrbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, DMA_EN);
+
+	writel(1, priv->mac_reg + UMAC_TX_FLUSH);
+	udelay(10);
+	writel(0, priv->mac_reg + UMAC_TX_FLUSH);
+}
+
+static void bcmgenet_enable_dma(struct bcmgenet_eth_priv *priv)
+{
+	u32 dma_ctrl = (1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT)) | DMA_EN;
+
+	writel(dma_ctrl, priv->mac_reg + TDMA_REG_BASE + DMA_CTRL);
+
+	setbits_32(priv->mac_reg + RDMA_REG_BASE + DMA_CTRL, dma_ctrl);
+}
+
+static int bcmgenet_gmac_eth_send(struct udevice *dev, void *packet, int length)
+{
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	void *desc_base = priv->tx_desc_base + priv->tx_index * DMA_DESC_SIZE;
+	u32 len_stat = length << DMA_BUFLENGTH_SHIFT;
+	ulong packet_aligned = rounddown((ulong)packet, ARCH_DMA_MINALIGN);
+	u32 prod_index, cons;
+	u32 tries = 100;
+
+	prod_index = readl(priv->mac_reg + TDMA_PROD_INDEX);
+
+	/* There is actually no reason for the rounding here, but the ARMv7
+	 * implementation of flush_dcache_range() checks for aligned
+	 * boundaries of the flushed range.
+	 * Adjust them here to pass that check and avoid misleading messages.
+	 */
+	flush_dcache_range(packet_aligned,
+			   packet_aligned + roundup(length, ARCH_DMA_MINALIGN));
+
+	len_stat |= 0x3F << DMA_TX_QTAG_SHIFT;
+	len_stat |= DMA_TX_APPEND_CRC | DMA_SOP | DMA_EOP;
+
+	/* Set-up packet for transmission */
+	writel(lower_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_LO));
+	writel(upper_32_bits((ulong)packet), (desc_base + DMA_DESC_ADDRESS_HI));
+	writel(len_stat, (desc_base + DMA_DESC_LENGTH_STATUS));
+
+	/* Increment index and start transmission */
+	if (++priv->tx_index >= TX_DESCS)
+		priv->tx_index = 0;
+
+	prod_index++;
+
+	/* Start Transmisson */
+	writel(prod_index, priv->mac_reg + TDMA_PROD_INDEX);
+
+	do {
+		cons = readl(priv->mac_reg + TDMA_CONS_INDEX);
+	} while ((cons & 0xffff) < prod_index && --tries);
+	if (!tries)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+/* Check whether all cache lines affected by an invalidate are within
+ * the buffer, to make sure we don't accidentally lose unrelated dirty
+ * data stored nearby.
+ * Alignment of the buffer start address will be checked in the implementation
+ * of invalidate_dcache_range().
+ */
+static void invalidate_dcache_check(unsigned long addr, size_t size,
+				    size_t buffer_size)
+{
+	size_t inval_size = roundup(size, ARCH_DMA_MINALIGN);
+
+	if (unlikely(inval_size > buffer_size))
+		printf("WARNING: Cache invalidate area exceeds buffer size\n");
+
+	invalidate_dcache_range(addr, addr + inval_size);
+}
+
+static int bcmgenet_gmac_eth_recv(struct udevice *dev,
+				  int flags, uchar **packetp)
+{
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	void *desc_base = priv->rx_desc_base + priv->rx_index * DMA_DESC_SIZE;
+	u32 prod_index = readl(priv->mac_reg + RDMA_PROD_INDEX);
+	u32 length, addr;
+
+	if (prod_index == priv->c_index)
+		return -EAGAIN;
+
+	length = readl(desc_base + DMA_DESC_LENGTH_STATUS);
+	length = (length >> DMA_BUFLENGTH_SHIFT) & DMA_BUFLENGTH_MASK;
+	addr = readl(desc_base + DMA_DESC_ADDRESS_LO);
+
+	invalidate_dcache_check(addr, length, RX_BUF_LENGTH);
+
+	/* To cater for the IP header alignment the hardware does.
+	 * This would actually not be needed if we don't program
+	 * RBUF_ALIGN_2B
+	 */
+	*packetp = (uchar *)(ulong)addr + RX_BUF_OFFSET;
+
+	return length - RX_BUF_OFFSET;
+}
+
+static int bcmgenet_gmac_free_pkt(struct udevice *dev, uchar *packet,
+				  int length)
+{
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+
+	/* Tell the MAC we have consumed that last receive buffer. */
+	priv->c_index = (priv->c_index + 1) & 0xFFFF;
+	writel(priv->c_index, priv->mac_reg + RDMA_CONS_INDEX);
+
+	/* Forward our descriptor pointer, wrapping around if needed. */
+	if (++priv->rx_index >= RX_DESCS)
+		priv->rx_index = 0;
+
+	return 0;
+}
+
+static void rx_descs_init(struct bcmgenet_eth_priv *priv)
+{
+	char *rxbuffs = &priv->rxbuffer[0];
+	u32 len_stat, i;
+	void *desc_base = priv->rx_desc_base;
+
+	priv->c_index = 0;
+
+	len_stat = (RX_BUF_LENGTH << DMA_BUFLENGTH_SHIFT) | DMA_OWN;
+
+	for (i = 0; i < RX_DESCS; i++) {
+		writel(lower_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
+		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_LO);
+		writel(upper_32_bits((uintptr_t)&rxbuffs[i * RX_BUF_LENGTH]),
+		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_ADDRESS_HI);
+		writel(len_stat,
+		       desc_base + i * DMA_DESC_SIZE + DMA_DESC_LENGTH_STATUS);
+	}
+}
+
+static void rx_ring_init(struct bcmgenet_eth_priv *priv)
+{
+	writel(DMA_MAX_BURST_LENGTH,
+	       priv->mac_reg + RDMA_REG_BASE + DMA_SCB_BURST_SIZE);
+
+	writel(0x0, priv->mac_reg + RDMA_RING_REG_BASE + DMA_START_ADDR);
+	writel(0x0, priv->mac_reg + RDMA_READ_PTR);
+	writel(0x0, priv->mac_reg + RDMA_WRITE_PTR);
+	writel(RX_DESCS * DMA_DESC_SIZE / 4 - 1,
+	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_END_ADDR);
+
+	writel(0x0, priv->mac_reg + RDMA_PROD_INDEX);
+	writel(0x0, priv->mac_reg + RDMA_CONS_INDEX);
+	writel((RX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
+	       priv->mac_reg + RDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
+	writel(DMA_FC_THRESH_VALUE, priv->mac_reg + RDMA_XON_XOFF_THRESH);
+	writel(1 << DEFAULT_Q, priv->mac_reg + RDMA_REG_BASE + DMA_RING_CFG);
+}
+
+static void tx_ring_init(struct bcmgenet_eth_priv *priv)
+{
+	writel(DMA_MAX_BURST_LENGTH,
+	       priv->mac_reg + TDMA_REG_BASE + DMA_SCB_BURST_SIZE);
+
+	writel(0x0, priv->mac_reg + TDMA_RING_REG_BASE + DMA_START_ADDR);
+	writel(0x0, priv->mac_reg + TDMA_READ_PTR);
+	writel(0x0, priv->mac_reg + TDMA_WRITE_PTR);
+	writel(TX_DESCS * DMA_DESC_SIZE / 4 - 1,
+	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_END_ADDR);
+	writel(0x0, priv->mac_reg + TDMA_PROD_INDEX);
+	writel(0x0, priv->mac_reg + TDMA_CONS_INDEX);
+	writel(0x1, priv->mac_reg + TDMA_RING_REG_BASE + DMA_MBUF_DONE_THRESH);
+	writel(0x0, priv->mac_reg + TDMA_FLOW_PERIOD);
+	writel((TX_DESCS << DMA_RING_SIZE_SHIFT) | RX_BUF_LENGTH,
+	       priv->mac_reg + TDMA_RING_REG_BASE + DMA_RING_BUF_SIZE);
+
+	writel(1 << DEFAULT_Q, priv->mac_reg + TDMA_REG_BASE + DMA_RING_CFG);
+}
+
+static int bcmgenet_adjust_link(struct bcmgenet_eth_priv *priv)
+{
+	struct phy_device *phy_dev = priv->phydev;
+	u32 speed;
+
+	switch (phy_dev->speed) {
+	case SPEED_1000:
+		speed = UMAC_SPEED_1000;
+		break;
+	case SPEED_100:
+		speed = UMAC_SPEED_100;
+		break;
+	case SPEED_10:
+		speed = UMAC_SPEED_10;
+		break;
+	default:
+		printf("bcmgenet: Unsupported PHY speed: %d\n", phy_dev->speed);
+		return -EINVAL;
+	}
+
+	clrsetbits_32(priv->mac_reg + EXT_RGMII_OOB_CTRL, OOB_DISABLE,
+			RGMII_LINK | RGMII_MODE_EN | ID_MODE_DIS);
+
+	writel(speed << CMD_SPEED_SHIFT, (priv->mac_reg + UMAC_CMD));
+
+	return 0;
+}
+
+static int bcmgenet_gmac_eth_start(struct udevice *dev)
+{
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	priv->tx_desc_base = priv->mac_reg + GENET_TX_OFF;
+	priv->rx_desc_base = priv->mac_reg + GENET_RX_OFF;
+	priv->tx_index = 0x0;
+	priv->rx_index = 0x0;
+
+	bcmgenet_umac_reset(priv);
+
+	bcmgenet_gmac_write_hwaddr(dev);
+
+	/* Disable RX/TX DMA and flush TX queues */
+	bcmgenet_disable_dma(priv);
+
+	rx_ring_init(priv);
+	rx_descs_init(priv);
+
+	tx_ring_init(priv);
+
+	/* Enable RX/TX DMA */
+	bcmgenet_enable_dma(priv);
+
+	/* read PHY properties over the wire from generic PHY set-up */
+	ret = phy_startup(priv->phydev);
+	if (ret) {
+		printf("bcmgenet: PHY startup failed: %d\n", ret);
+		return ret;
+	}
+
+	/* Update MAC registers based on PHY property */
+	ret = bcmgenet_adjust_link(priv);
+	if (ret) {
+		printf("bcmgenet: adjust PHY link failed: %d\n", ret);
+		return ret;
+	}
+
+	/* Enable Rx/Tx */
+	setbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
+
+	return 0;
+}
+
+static int bcmgenet_phy_init(struct bcmgenet_eth_priv *priv, void *dev)
+{
+	struct phy_device *phydev;
+	int ret;
+
+	phydev = phy_connect(priv->bus, priv->phyaddr, dev, priv->interface);
+	if (!phydev)
+		return -ENODEV;
+
+	phydev->supported &= PHY_GBIT_FEATURES;
+	if (priv->speed) {
+		ret = phy_set_supported(priv->phydev, priv->speed);
+		if (ret)
+			return ret;
+	}
+	phydev->advertising = phydev->supported;
+
+	phy_connect_dev(phydev, dev);
+
+	priv->phydev = phydev;
+	phy_config(priv->phydev);
+
+	return 0;
+}
+
+static void bcmgenet_mdio_start(struct bcmgenet_eth_priv *priv)
+{
+	setbits_32(priv->mac_reg + MDIO_CMD, MDIO_START_BUSY);
+}
+
+static int bcmgenet_mdio_write(struct mii_dev *bus, int addr, int devad,
+			       int reg, u16 value)
+{
+	struct udevice *dev = bus->priv;
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	u32 val;
+
+	/* Prepare the read operation */
+	val = MDIO_WR | (addr << MDIO_PMD_SHIFT) |
+		(reg << MDIO_REG_SHIFT) | (0xffff & value);
+	writel_relaxed(val,  priv->mac_reg + MDIO_CMD);
+
+	/* Start MDIO transaction */
+	bcmgenet_mdio_start(priv);
+
+	return wait_for_bit_32(priv->mac_reg + MDIO_CMD,
+			       MDIO_START_BUSY, false, 20, true);
+}
+
+static int bcmgenet_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
+{
+	struct udevice *dev = bus->priv;
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	u32 val;
+	int ret;
+
+	/* Prepare the read operation */
+	val = MDIO_RD | (addr << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
+	writel_relaxed(val, priv->mac_reg + MDIO_CMD);
+
+	/* Start MDIO transaction */
+	bcmgenet_mdio_start(priv);
+
+	ret = wait_for_bit_32(priv->mac_reg + MDIO_CMD,
+			      MDIO_START_BUSY, false, 20, true);
+	if (ret)
+		return ret;
+
+	val = readl_relaxed(priv->mac_reg + MDIO_CMD);
+
+	return val & 0xffff;
+}
+
+static int bcmgenet_mdio_init(const char *name, struct udevice *priv)
+{
+	struct mii_dev *bus = mdio_alloc();
+
+	if (!bus) {
+		debug("Failed to allocate MDIO bus\n");
+		return -ENOMEM;
+	}
+
+	bus->read = bcmgenet_mdio_read;
+	bus->write = bcmgenet_mdio_write;
+	snprintf(bus->name, sizeof(bus->name), name);
+	bus->priv = (void *)priv;
+
+	return mdio_register(bus);
+}
+
+/* We only support RGMII (as used on the RPi4). */
+static int bcmgenet_interface_set(struct bcmgenet_eth_priv *priv)
+{
+	phy_interface_t phy_mode = priv->interface;
+
+	switch (phy_mode) {
+	case PHY_INTERFACE_MODE_RGMII:
+	case PHY_INTERFACE_MODE_RGMII_RXID:
+		writel(PORT_MODE_EXT_GPHY, priv->mac_reg + SYS_PORT_CTRL);
+		break;
+	default:
+		printf("unknown phy mode: %d\n", priv->interface);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int bcmgenet_eth_probe(struct udevice *dev)
+{
+	struct eth_pdata *pdata = dev_get_platdata(dev);
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	ofnode mdio_node;
+	const char *name;
+	u32 reg;
+	int ret;
+	u8 major;
+
+	priv->mac_reg = map_physmem(pdata->iobase, SZ_64K, MAP_NOCACHE);
+	priv->interface = pdata->phy_interface;
+	priv->speed = pdata->max_speed;
+
+	/* Read GENET HW version */
+	reg = readl_relaxed(priv->mac_reg + SYS_REV_CTRL);
+	major = (reg >> 24) & 0x0f;
+	if (major != 6) {
+		if (major == 5)
+			major = 4;
+		else if (major == 0)
+			major = 1;
+
+		printf("Unsupported GENETv%d.%d\n", major, (reg >> 16) & 0x0f);
+		return -ENODEV;
+	}
+
+	ret = bcmgenet_interface_set(priv);
+	if (ret)
+		return ret;
+
+	mdio_node = dev_read_first_subnode(dev);
+	name = ofnode_get_name(mdio_node);
+
+	ret = bcmgenet_mdio_init(name, dev);
+	if (ret)
+		return ret;
+
+	priv->bus = miiphy_get_dev_by_name(name);
+
+	return bcmgenet_phy_init(priv, dev);
+}
+
+static void bcmgenet_gmac_eth_stop(struct udevice *dev)
+{
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+
+	clrbits_32(priv->mac_reg + UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
+	clrbits_32(priv->mac_reg + TDMA_REG_BASE + DMA_CTRL,
+		     1 << (DEFAULT_Q + DMA_RING_BUF_EN_SHIFT) | DMA_EN);
+}
+
+static const struct eth_ops bcmgenet_gmac_eth_ops = {
+	.start                  = bcmgenet_gmac_eth_start,
+	.write_hwaddr           = bcmgenet_gmac_write_hwaddr,
+	.send                   = bcmgenet_gmac_eth_send,
+	.recv                   = bcmgenet_gmac_eth_recv,
+	.free_pkt               = bcmgenet_gmac_free_pkt,
+	.stop                   = bcmgenet_gmac_eth_stop,
+};
+
+static int bcmgenet_eth_ofdata_to_platdata(struct udevice *dev)
+{
+	struct eth_pdata *pdata = dev_get_platdata(dev);
+	struct bcmgenet_eth_priv *priv = dev_get_priv(dev);
+	struct ofnode_phandle_args phy_node;
+	const char *phy_mode;
+	int ret;
+
+	pdata->iobase = dev_read_addr(dev);
+
+	/* Get phy mode from DT */
+	pdata->phy_interface = -1;
+	phy_mode = dev_read_string(dev, "phy-mode");
+	if (phy_mode)
+		pdata->phy_interface = phy_get_interface_by_name(phy_mode);
+	if (pdata->phy_interface == -1) {
+		debug("%s: Invalid PHY interface '%s'\n", __func__, phy_mode);
+		return -EINVAL;
+	}
+
+	ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0,
+					 &phy_node);
+	if (!ret) {
+		ofnode_read_s32(phy_node.node, "reg", &priv->phyaddr);
+		ofnode_read_s32(phy_node.node, "max-speed", &pdata->max_speed);
+	}
+
+	return 0;
+}
+
+/* The BCM2711 implementation has a limited burst length compared to a generic
+ * GENETv5 version, but we go with that shorter value (8) in both cases, for
+ * the sake of simplicity.
+ */
+static const struct udevice_id bcmgenet_eth_ids[] = {
+	{.compatible = "brcm,genet-v5"},
+	{.compatible = "brcm,bcm2711-genet-v5"},
+	{}
+};
+
+U_BOOT_DRIVER(eth_bcmgenet) = {
+	.name   = "eth_bcmgenet",
+	.id     = UCLASS_ETH,
+	.of_match = bcmgenet_eth_ids,
+	.ofdata_to_platdata = bcmgenet_eth_ofdata_to_platdata,
+	.probe  = bcmgenet_eth_probe,
+	.ops    = &bcmgenet_gmac_eth_ops,
+	.priv_auto_alloc_size = sizeof(struct bcmgenet_eth_priv),
+	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
+	.flags = DM_FLAG_ALLOC_PRIV_DMA,
+};