[4/6] pci: uniphier: Add UniPhier PCIe controller driver

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index b2b7b25..6b35455 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -328,4 +328,14 @@  config PCI_BRCMSTB
 	  on Broadcom set-top-box (STB) SoCs.
 	  This driver currently supports only BCM2711 SoC and RC mode
 	  of the controller.
+
+config PCIE_UNIPHIER
+	bool "Socionext UniPhier PCIe driver"
+	depends on DM_PCI
+	depends on ARCH_UNIPHIER
+	select PHY_UNIPHIER_PCIE
+	help
+	  Say Y here if you want to enable PCIe controller support on
+	  UniPhier SoCs.
+
 endif
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index c742bb2..73dee64 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -55,3 +55,4 @@  obj-$(CONFIG_PCI_BRCMSTB) += pcie_brcmstb.o
 obj-$(CONFIG_PCI_OCTEONTX) += pci_octeontx.o
 obj-$(CONFIG_PCIE_OCTEON) += pcie_octeon.o
 obj-$(CONFIG_PCIE_DW_SIFIVE) += pcie_dw_sifive.o
+obj-$(CONFIG_PCIE_UNIPHIER) += pcie_uniphier.o
diff --git a/drivers/pci/pcie_uniphier.c b/drivers/pci/pcie_uniphier.c
new file mode 100644
index 0000000..f2edea9
--- /dev/null
+++ b/drivers/pci/pcie_uniphier.c
@@ -0,0 +1,424 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * pcie_uniphier.c - Socionext UniPhier PCIe driver
+ * Copyright 2019-2021 Socionext, Inc.
+ */
+
+#include <clk.h>
+#include <common.h>
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <generic-phy.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/compat.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <pci.h>
+#include <reset.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* DBI registers */
+#define PCIE_LINK_STATUS_REG		0x0080
+#define PCIE_LINK_STATUS_WIDTH_MASK	GENMASK(25, 20)
+#define PCIE_LINK_STATUS_SPEED_MASK	GENMASK(19, 16)
+
+#define PCIE_MISC_CONTROL_1_OFF		0x08BC
+#define PCIE_DBI_RO_WR_EN		BIT(0)
+
+/* DBI iATU registers */
+#define PCIE_ATU_VIEWPORT		0x0900
+#define PCIE_ATU_REGION_INBOUND		BIT(31)
+#define PCIE_ATU_REGION_OUTBOUND	0
+#define PCIE_ATU_REGION_INDEX_MASK	GENMASK(3, 0)
+
+#define PCIE_ATU_CR1			0x0904
+#define PCIE_ATU_TYPE_MEM		0
+#define PCIE_ATU_TYPE_IO		2
+#define PCIE_ATU_TYPE_CFG0		4
+#define PCIE_ATU_TYPE_CFG1		5
+
+#define PCIE_ATU_CR2			0x0908
+#define PCIE_ATU_ENABLE			BIT(31)
+#define PCIE_ATU_MATCH_MODE		BIT(30)
+#define PCIE_ATU_BAR_NUM_MASK		GENMASK(10, 8)
+
+#define PCIE_ATU_LOWER_BASE		0x090C
+#define PCIE_ATU_UPPER_BASE		0x0910
+#define PCIE_ATU_LIMIT			0x0914
+#define PCIE_ATU_LOWER_TARGET		0x0918
+#define PCIE_ATU_BUS(x)			FIELD_PREP(GENMASK(31, 24), x)
+#define PCIE_ATU_DEV(x)			FIELD_PREP(GENMASK(23, 19), x)
+#define PCIE_ATU_FUNC(x)		FIELD_PREP(GENMASK(18, 16), x)
+#define PCIE_ATU_UPPER_TARGET		0x091C
+
+/* Link Glue registers */
+#define PCL_PINCTRL0			0x002c
+#define PCL_PERST_PLDN_REGEN		BIT(12)
+#define PCL_PERST_NOE_REGEN		BIT(11)
+#define PCL_PERST_OUT_REGEN		BIT(8)
+#define PCL_PERST_PLDN_REGVAL		BIT(4)
+#define PCL_PERST_NOE_REGVAL		BIT(3)
+#define PCL_PERST_OUT_REGVAL		BIT(0)
+
+#define PCL_MODE			0x8000
+#define PCL_MODE_REGEN			BIT(8)
+#define PCL_MODE_REGVAL			BIT(0)
+
+#define PCL_APP_READY_CTRL		0x8008
+#define PCL_APP_LTSSM_ENABLE		BIT(0)
+
+#define PCL_APP_PM0			0x8078
+#define PCL_SYS_AUX_PWR_DET		BIT(8)
+
+#define PCL_STATUS_LINK			0x8140
+#define PCL_RDLH_LINK_UP		BIT(1)
+#define PCL_XMLH_LINK_UP		BIT(0)
+
+#define LINK_UP_TIMEOUT_MS		100
+
+struct uniphier_pcie_priv {
+	void *base;
+	void *dbi_base;
+	void *cfg_base;
+	fdt_size_t cfg_size;
+	struct fdt_resource link_res;
+	struct fdt_resource dbi_res;
+	struct fdt_resource cfg_res;
+
+	struct clk clk;
+	struct reset_ctl rst;
+	struct phy phy;
+
+	struct pci_region io;
+	struct pci_region mem;
+};
+
+static int pcie_dw_get_link_speed(struct uniphier_pcie_priv *priv)
+{
+	u32 val = readl(priv->dbi_base + PCIE_LINK_STATUS_REG);
+
+	return FIELD_GET(PCIE_LINK_STATUS_SPEED_MASK, val);
+}
+
+static int pcie_dw_get_link_width(struct uniphier_pcie_priv *priv)
+{
+	u32 val = readl(priv->dbi_base + PCIE_LINK_STATUS_REG);
+
+	return FIELD_GET(PCIE_LINK_STATUS_WIDTH_MASK, val);
+}
+
+static void pcie_dw_prog_outbound_atu(struct uniphier_pcie_priv *priv,
+				      int index, int type, u64 cpu_addr,
+				      u64 pci_addr, u32 size)
+{
+	writel(PCIE_ATU_REGION_OUTBOUND
+	       | FIELD_PREP(PCIE_ATU_REGION_INDEX_MASK, index),
+	       priv->dbi_base + PCIE_ATU_VIEWPORT);
+	writel(lower_32_bits(cpu_addr),
+	       priv->dbi_base + PCIE_ATU_LOWER_BASE);
+	writel(upper_32_bits(cpu_addr),
+	       priv->dbi_base + PCIE_ATU_UPPER_BASE);
+	writel(lower_32_bits(cpu_addr + size - 1),
+	       priv->dbi_base + PCIE_ATU_LIMIT);
+	writel(lower_32_bits(pci_addr),
+	       priv->dbi_base + PCIE_ATU_LOWER_TARGET);
+	writel(upper_32_bits(pci_addr),
+	       priv->dbi_base + PCIE_ATU_UPPER_TARGET);
+
+	writel(type, priv->dbi_base + PCIE_ATU_CR1);
+	writel(PCIE_ATU_ENABLE, priv->dbi_base + PCIE_ATU_CR2);
+}
+
+static int uniphier_pcie_addr_valid(pci_dev_t bdf, int first_busno)
+{
+	/* accept only device {0,1} on first bus */
+	if ((PCI_BUS(bdf) != first_busno) || (PCI_DEV(bdf) > 1))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int uniphier_pcie_conf_address(const struct udevice *dev, pci_dev_t bdf,
+				      uint offset, void **paddr)
+{
+	struct uniphier_pcie_priv *priv = dev_get_priv(dev);
+	u32 busdev;
+	int seq = dev_seq(dev);
+	int ret;
+
+	ret = uniphier_pcie_addr_valid(bdf, seq);
+	if (ret)
+		return ret;
+
+	if ((PCI_BUS(bdf) == seq) && !PCI_DEV(bdf)) {
+		*paddr = (void *)(priv->dbi_base + offset);
+		return 0;
+	}
+
+	busdev = PCIE_ATU_BUS(PCI_BUS(bdf) - seq)
+		| PCIE_ATU_DEV(PCI_DEV(bdf))
+		| PCIE_ATU_FUNC(PCI_FUNC(bdf));
+
+	pcie_dw_prog_outbound_atu(priv, 0,
+				  PCIE_ATU_TYPE_CFG0, (u64)priv->cfg_base,
+				  busdev, priv->cfg_size);
+	*paddr = (void *)(priv->cfg_base + offset);
+
+	return 0;
+}
+
+static int uniphier_pcie_read_config(const struct udevice *dev, pci_dev_t bdf,
+				     uint offset, ulong *valp,
+				     enum pci_size_t size)
+{
+	return pci_generic_mmap_read_config(dev, uniphier_pcie_conf_address,
+					    bdf, offset, valp, size);
+}
+
+static int uniphier_pcie_write_config(struct udevice *dev, pci_dev_t bdf,
+				      uint offset, ulong val,
+				      enum pci_size_t size)
+{
+	return pci_generic_mmap_write_config(dev, uniphier_pcie_conf_address,
+					     bdf, offset, val, size);
+}
+
+static void uniphier_pcie_ltssm_enable(struct uniphier_pcie_priv *priv,
+				       bool enable)
+{
+	u32 val;
+
+	val = readl(priv->base + PCL_APP_READY_CTRL);
+	if (enable)
+		val |= PCL_APP_LTSSM_ENABLE;
+	else
+		val &= ~PCL_APP_LTSSM_ENABLE;
+	writel(val, priv->base + PCL_APP_READY_CTRL);
+}
+
+static int uniphier_pcie_link_up(struct uniphier_pcie_priv *priv)
+{
+	u32 val, mask;
+
+	val = readl(priv->base + PCL_STATUS_LINK);
+	mask = PCL_RDLH_LINK_UP | PCL_XMLH_LINK_UP;
+
+	return (val & mask) == mask;
+}
+
+static int uniphier_pcie_wait_link(struct uniphier_pcie_priv *priv)
+{
+	unsigned long timeout;
+
+	timeout = get_timer(0) + LINK_UP_TIMEOUT_MS;
+
+	while (get_timer(0) < timeout) {
+		if (uniphier_pcie_link_up(priv))
+			return 0;
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int uniphier_pcie_establish_link(struct uniphier_pcie_priv *priv)
+{
+	if (uniphier_pcie_link_up(priv))
+		return 0;
+
+	uniphier_pcie_ltssm_enable(priv, true);
+
+	return uniphier_pcie_wait_link(priv);
+}
+
+static void uniphier_pcie_init_rc(struct uniphier_pcie_priv *priv)
+{
+	u32 val;
+
+	/* set RC mode */
+	val = readl(priv->base + PCL_MODE);
+	val |= PCL_MODE_REGEN;
+	val &= ~PCL_MODE_REGVAL;
+	writel(val, priv->base + PCL_MODE);
+
+	/* use auxiliary power detection */
+	val = readl(priv->base + PCL_APP_PM0);
+	val |= PCL_SYS_AUX_PWR_DET;
+	writel(val, priv->base + PCL_APP_PM0);
+
+	/* assert PERST# */
+	val = readl(priv->base + PCL_PINCTRL0);
+	val &= ~(PCL_PERST_NOE_REGVAL | PCL_PERST_OUT_REGVAL
+		 | PCL_PERST_PLDN_REGVAL);
+	val |= PCL_PERST_NOE_REGEN | PCL_PERST_OUT_REGEN
+		| PCL_PERST_PLDN_REGEN;
+	writel(val, priv->base + PCL_PINCTRL0);
+
+	uniphier_pcie_ltssm_enable(priv, false);
+
+	mdelay(100);
+
+	/* deassert PERST# */
+	val = readl(priv->base + PCL_PINCTRL0);
+	val |= PCL_PERST_OUT_REGVAL | PCL_PERST_OUT_REGEN;
+	writel(val, priv->base + PCL_PINCTRL0);
+}
+
+static void uniphier_pcie_setup_rc(struct uniphier_pcie_priv *priv,
+				   struct pci_controller *hose)
+{
+	/* Store the IO and MEM windows settings for future use by the ATU */
+	priv->io.phys_start  = hose->regions[0].phys_start; /* IO base */
+	priv->io.bus_start   = hose->regions[0].bus_start;  /* IO_bus_addr */
+	priv->io.size	     = hose->regions[0].size;	    /* IO size */
+	priv->mem.phys_start = hose->regions[1].phys_start; /* MEM base */
+	priv->mem.bus_start  = hose->regions[1].bus_start;  /* MEM_bus_addr */
+	priv->mem.size	     = hose->regions[1].size;	    /* MEM size */
+
+	/* outbound: IO */
+	pcie_dw_prog_outbound_atu(priv, 0,
+				  PCIE_ATU_TYPE_IO, priv->io.phys_start,
+				  priv->io.bus_start, priv->io.size);
+
+	/* outbound: MEM */
+	pcie_dw_prog_outbound_atu(priv, 1,
+				  PCIE_ATU_TYPE_MEM, priv->mem.phys_start,
+				  priv->mem.bus_start, priv->mem.size);
+}
+
+static int uniphier_pcie_probe(struct udevice *dev)
+{
+	struct uniphier_pcie_priv *priv = dev_get_priv(dev);
+	struct udevice *ctlr = pci_get_controller(dev);
+	struct pci_controller *hose = dev_get_uclass_priv(ctlr);
+	int ret;
+
+	priv->base = map_physmem(priv->link_res.start,
+				 fdt_resource_size(&priv->link_res),
+				 MAP_NOCACHE);
+	priv->dbi_base = map_physmem(priv->dbi_res.start,
+				     fdt_resource_size(&priv->dbi_res),
+				     MAP_NOCACHE);
+	priv->cfg_size = fdt_resource_size(&priv->cfg_res);
+	priv->cfg_base = map_physmem(priv->cfg_res.start,
+				     priv->cfg_size, MAP_NOCACHE);
+
+	ret = clk_enable(&priv->clk);
+	if (ret) {
+		dev_err(dev, "Failed to enable clk: %d\n", ret);
+		return ret;
+	}
+	ret = reset_deassert(&priv->rst);
+	if (ret) {
+		dev_err(dev, "Failed to deassert reset: %d\n", ret);
+		goto out_clk_release;
+	}
+
+	ret = generic_phy_init(&priv->phy);
+	if (ret) {
+		dev_err(dev, "Failed to initialize phy: %d\n", ret);
+		goto out_reset_release;
+	}
+
+	ret = generic_phy_power_on(&priv->phy);
+	if (ret) {
+		dev_err(dev, "Failed to power on phy: %d\n", ret);
+		goto out_phy_exit;
+	}
+
+	uniphier_pcie_init_rc(priv);
+
+	/* set DBI to read only */
+	writel(0, priv->dbi_base + PCIE_MISC_CONTROL_1_OFF);
+
+	uniphier_pcie_setup_rc(priv, hose);
+
+	if (uniphier_pcie_establish_link(priv)) {
+		printf("PCIE-%d: Link down\n", dev_seq(dev));
+	} else {
+		printf("PCIE-%d: Link up (Gen%d-x%d, Bus%d)\n",
+		       dev_seq(dev), pcie_dw_get_link_speed(priv),
+		       pcie_dw_get_link_width(priv), hose->first_busno);
+	}
+
+	return 0;
+
+out_phy_exit:
+	generic_phy_exit(&priv->phy);
+out_reset_release:
+	reset_release_all(&priv->rst, 1);
+out_clk_release:
+	clk_release_all(&priv->clk, 1);
+
+	return ret;
+}
+
+static int uniphier_pcie_of_to_plat(struct udevice *dev)
+{
+	struct uniphier_pcie_priv *priv = dev_get_priv(dev);
+	const void *fdt = gd->fdt_blob;
+	int node = dev_of_offset(dev);
+	int ret;
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "link", &priv->link_res);
+	if (ret) {
+		dev_err(dev, "Failed to get link regs: %d\n", ret);
+		return ret;
+	}
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "dbi", &priv->dbi_res);
+	if (ret) {
+		dev_err(dev, "Failed to get dbi regs: %d\n", ret);
+		return ret;
+	}
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "config", &priv->cfg_res);
+	if (ret) {
+		dev_err(dev, "Failed to get config regs: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_get_by_index(dev, 0, &priv->clk);
+	if (ret) {
+		dev_err(dev, "Failed to get clocks property: %d\n", ret);
+		return ret;
+	}
+
+	ret = reset_get_by_index(dev, 0, &priv->rst);
+	if (ret) {
+		dev_err(dev, "Failed to get resets property: %d\n", ret);
+		return ret;
+	}
+
+	ret = generic_phy_get_by_index(dev, 0, &priv->phy);
+	if (ret) {
+		dev_err(dev, "Failed to get phy property: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dm_pci_ops uniphier_pcie_ops = {
+	.read_config	= uniphier_pcie_read_config,
+	.write_config	= uniphier_pcie_write_config,
+};
+
+static const struct udevice_id uniphier_pcie_ids[] = {
+	{ .compatible = "socionext,uniphier-pcie", },
+	{ /* Sentinel */ }
+};
+
+U_BOOT_DRIVER(pcie_uniphier) = {
+	.name     = "uniphier-pcie",
+	.id       = UCLASS_PCI,
+	.of_match = uniphier_pcie_ids,
+	.probe    = uniphier_pcie_probe,
+	.ops      = &uniphier_pcie_ops,
+	.of_to_plat = uniphier_pcie_of_to_plat,
+	.priv_auto = sizeof(struct uniphier_pcie_priv),
+};