diff mbox series

[v7,11/13] slimbus: qcom: Add Qualcomm Slimbus controller driver

Message ID 20171115141043.29202-12-srinivas.kandagatla@linaro.org
State Superseded
Headers show
Series [v7,01/13] Documentation: Add SLIMbus summary | expand

Commit Message

Srinivas Kandagatla Nov. 15, 2017, 2:10 p.m. UTC
From: Sagar Dharia <sdharia@codeaurora.org>


This controller driver programs manager, interface, and framer
devices for Qualcomm's slimbus HW block.
Manager component currently implements logical address setting,
and messaging interface.
Interface device reports bus synchronization information, and framer
device clocks the bus from the time it's woken up, until clock-pause
is executed by the manager device.

Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

---
 drivers/slimbus/Kconfig     |   6 +
 drivers/slimbus/Makefile    |   4 +
 drivers/slimbus/qcom-ctrl.c | 684 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 694 insertions(+)
 create mode 100644 drivers/slimbus/qcom-ctrl.c

-- 
2.15.0

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Comments

Charles Keepax Nov. 23, 2017, 10:07 a.m. UTC | #1
On Wed, Nov 15, 2017 at 02:10:41PM +0000, srinivas.kandagatla@linaro.org wrote:
> From: Sagar Dharia <sdharia@codeaurora.org>

> 

> This controller driver programs manager, interface, and framer

> devices for Qualcomm's slimbus HW block.

> Manager component currently implements logical address setting,

> and messaging interface.

> Interface device reports bus synchronization information, and framer

> device clocks the bus from the time it's woken up, until clock-pause

> is executed by the manager device.

> 

> Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>

> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

> ---

> +

> +static irqreturn_t qcom_slim_handle_rx_irq(struct qcom_slim_ctrl *ctrl,

> +					   u32 stat)

> +{

> +	u32 *rx_buf, pkt[10];

> +	bool q_rx = false;

> +	u8 la, *buf, mc, mt, len, *b = (u8 *)&pkt[0];

> +	u16 ele;

> +


This function feels pretty funky, we basically have rx_buf, pkt,
b and buf all of which basically point to the same thing. Can we
simplify it a little?

> +	pkt[0] = readl_relaxed(ctrl->base + MGR_RX_MSG);

> +	mt = SLIM_HEADER_GET_MT(b[0]);

> +	len = SLIM_HEADER_GET_RL(b[0]);

> +	mc = SLIM_HEADER_GET_MC(b[1]);

> +

> +	/*

> +	 * this message cannot be handled by ISR, so

> +	 * let work-queue handle it

> +	 */

> +	if (mt == SLIM_MSG_MT_CORE &&

> +		mc == SLIM_MSG_MC_REPORT_PRESENT)

> +		rx_buf = (u32 *)slim_alloc_rxbuf(ctrl);

> +	else

> +		rx_buf = pkt;

> +

> +	if (rx_buf == NULL) {

> +		dev_err(ctrl->dev, "dropping RX:0x%x due to RX full\n",

> +					pkt[0]);

> +		goto rx_ret_irq;

> +	}

> +

> +	rx_buf[0] = pkt[0];


This is the only time that rx_buf is used without being cast to a
u8* would there be any milage in combining b and buf, and getting
rid of rx_buf?

> +	__ioread32_copy(rx_buf + 1, ctrl->base + MGR_RX_MSG + 4,

> +			DIV_ROUND_UP(len, 4));

> +

> +	switch (mc) {

> +

> +	case SLIM_MSG_MC_REPORT_PRESENT:

> +		q_rx = true;

> +		break;

> +	case SLIM_MSG_MC_REPLY_INFORMATION:

> +	case SLIM_MSG_MC_REPLY_VALUE:

> +		slim_msg_response(&ctrl->ctrl, (u8 *)(rx_buf + 1),

> +				  (u8)(*rx_buf >> 24), (len - 4));

> +		break;

> +	case SLIM_MSG_MC_REPORT_INFORMATION:

> +		buf = (u8 *)rx_buf;

> +		la = buf[2];

> +		ele = (u16)buf[4] << 4;

> +

> +		ele |= ((buf[3] & 0xf0) >> 4);

> +		/*

> +		 * report information is most likely loss of

> +		 * sync or collision detected in data slots

> +		 */

> +		dev_info(ctrl->dev, "LA:%d report inf ele:0x%x\n",

> +			 la, ele);

> +		break;

> +	default:

> +		dev_err(ctrl->dev, "unsupported MC,%x MT:%x\n",

> +			mc, mt);

> +		break;

> +	}

> +rx_ret_irq:

> +	writel(MGR_INT_RX_MSG_RCVD, ctrl->base +

> +		       MGR_INT_CLR);

> +	if (q_rx)

> +		queue_work(ctrl->rxwq, &ctrl->wd);

> +

> +	return IRQ_HANDLED;

> +}

> +

> +static int qcom_xfer_msg(struct slim_controller *sctrl,

> +			 struct slim_msg_txn *txn)

> +{

> +	struct qcom_slim_ctrl *ctrl = dev_get_drvdata(sctrl->dev);

> +	DECLARE_COMPLETION_ONSTACK(done);

> +	void *pbuf = slim_alloc_txbuf(ctrl, txn, &done);

> +	unsigned long ms = txn->rl + HZ;

> +	u8 *puc;

> +	int ret = 0, timeout, retries = QCOM_BUF_ALLOC_RETRIES;

> +	u8 la = txn->la;

> +	u32 *head;

> +	/* HW expects length field to be excluded */

> +	txn->rl--;

> +

> +	/* spin till buffer is made available */

> +	if (!pbuf) {

> +		while (retries--) {

> +			usleep_range(10000, 15000);

> +			pbuf = slim_alloc_txbuf(ctrl, txn, &done);

> +			if (pbuf)

> +				break;

> +		}

> +	}

> +

> +	if (!retries && !pbuf)

> +		return -ENOMEM;

> +

> +	puc = (u8 *)pbuf;

> +	head = (u32 *)pbuf;

> +

> +	if (txn->dt == SLIM_MSG_DEST_LOGICALADDR)

> +		*head = SLIM_MSG_ASM_FIRST_WORD(txn->rl, txn->mt, txn->mc, 0,

> +						la);

> +	else

> +		*head = SLIM_MSG_ASM_FIRST_WORD(txn->rl, txn->mt, txn->mc, 1,

> +						la);

> +

> +	if (txn->dt == SLIM_MSG_DEST_LOGICALADDR)

> +		puc += 3;

> +	else

> +		puc += 2;


Combine these two if statements, makes it much clearer the actions
are related.

> +

> +	if (txn->mt == SLIM_MSG_MT_CORE && slim_tid_txn(txn->mt, txn->mc))


slim_tid_txn checks for SLIM_MSG_MT_CORE so the check here should
be redundant.

> +		*(puc++) = txn->tid;

> +

> +	if ((txn->mt == SLIM_MSG_MT_CORE) &&

> +		((txn->mc >= SLIM_MSG_MC_REQUEST_INFORMATION &&

> +		txn->mc <= SLIM_MSG_MC_REPORT_INFORMATION) ||

> +		(txn->mc >= SLIM_MSG_MC_REQUEST_VALUE &&

> +		 txn->mc <= SLIM_MSG_MC_CHANGE_VALUE))) {

> +		*(puc++) = (txn->ec & 0xFF);

> +		*(puc++) = (txn->ec >> 8) & 0xFF;

> +	}


As you already have slim_tid_txn, would it be worth adding
something like slim_ec_txn? To state if an element code is
required, feels like other controls will probably want to do a
similar thing and would make the code a little more readable
here.

> +

> +	if (txn->msg && txn->msg->wbuf)

> +		memcpy(puc, txn->msg->wbuf, txn->msg->num_bytes);

> +

> +	qcom_slim_queue_tx(ctrl, head, txn->rl, MGR_TX_MSG);

> +	timeout = wait_for_completion_timeout(&done, msecs_to_jiffies(ms));

> +

> +	if (!timeout) {

> +		dev_err(ctrl->dev, "TX timed out:MC:0x%x,mt:0x%x", txn->mc,

> +					txn->mt);

> +		ret = -ETIMEDOUT;

> +	}

> +

> +	return ret;

> +

> +}

> +

> +static void qcom_slim_rxwq(struct work_struct *work)

> +{

> +	u8 buf[SLIM_MSGQ_BUF_LEN];

> +	u8 mc, mt, len;

> +	int i, ret;

> +	struct qcom_slim_ctrl *ctrl = container_of(work, struct qcom_slim_ctrl,

> +						 wd);

> +

> +	while ((slim_get_current_rxbuf(ctrl, buf)) != -ENODATA) {

> +		len = SLIM_HEADER_GET_RL(buf[0]);

> +		mt = SLIM_HEADER_GET_MT(buf[0]);

> +		mc = SLIM_HEADER_GET_MC(buf[1]);

> +		if (mt == SLIM_MSG_MT_CORE &&

> +			mc == SLIM_MSG_MC_REPORT_PRESENT) {

> +			u8 laddr;

> +			struct slim_eaddr ea;

> +			u8 e_addr[6];

> +

> +			for (i = 0; i < 6; i++)

> +				e_addr[i] = buf[7-i];

> +

> +			ea.manf_id = (u16)(e_addr[5] << 8) | e_addr[4];

> +			ea.prod_code = (u16)(e_addr[3] << 8) | e_addr[2];

> +			ea.dev_index = e_addr[1];

> +			ea.instance = e_addr[0];


If we are just bitshifting this out of the bytes does it really
make it much more clear to reverse the byte order first? Feels
like you might as well shift it out of buf directly.

Also we didn't bother to reverse the bytes for the element code
above, so feels more consistent.

> +			ret = slim_device_report_present(&ctrl->ctrl,

> +							 &ea, &laddr);

> +			if (ret < 0)

> +				dev_err(ctrl->dev, "assign laddr failed:%d\n",

> +					ret);

> +		} else {

> +			dev_err(ctrl->dev, "unexpected message:mc:%x, mt:%x\n",

> +				mc, mt);

> +		}

> +	}

> +}


Thanks,
Charles
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diff mbox series

Patch

diff --git a/drivers/slimbus/Kconfig b/drivers/slimbus/Kconfig
index 9c7d3c61656a..9c8d59290634 100644
--- a/drivers/slimbus/Kconfig
+++ b/drivers/slimbus/Kconfig
@@ -12,5 +12,11 @@  menuconfig SLIMBUS
 if SLIMBUS
 
 # SlIMbus controllers
+config SLIM_QCOM_CTRL
+	tristate "Qualcomm Slimbus Manager Component"
+	depends on SLIMBUS
+	help
+	  Select driver if Qualcomm's Slimbus Manager Component is
+	  programmed using Linux kernel.
 
 endif
diff --git a/drivers/slimbus/Makefile b/drivers/slimbus/Makefile
index 043402eae5be..9a70c7c70aae 100644
--- a/drivers/slimbus/Makefile
+++ b/drivers/slimbus/Makefile
@@ -3,3 +3,7 @@ 
 #
 obj-$(CONFIG_SLIMBUS)			+= slimbus.o
 slimbus-y				:= core.o messaging.o sched.o
+
+#Controllers
+obj-$(CONFIG_SLIM_QCOM_CTRL)		+= slim-qcom-ctrl.o
+slim-qcom-ctrl-y			:= qcom-ctrl.o
diff --git a/drivers/slimbus/qcom-ctrl.c b/drivers/slimbus/qcom-ctrl.c
new file mode 100644
index 000000000000..25c1974f04ec
--- /dev/null
+++ b/drivers/slimbus/qcom-ctrl.c
@@ -0,0 +1,684 @@ 
+/* Copyright (c) 2011-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/dma-mapping.h>
+#include "slimbus.h"
+
+/* Manager registers */
+#define	MGR_CFG		0x200
+#define	MGR_STATUS	0x204
+#define	MGR_INT_EN	0x210
+#define	MGR_INT_STAT	0x214
+#define	MGR_INT_CLR	0x218
+#define	MGR_TX_MSG	0x230
+#define	MGR_RX_MSG	0x270
+#define	MGR_IE_STAT	0x2F0
+#define	MGR_VE_STAT	0x300
+#define	MGR_CFG_ENABLE	1
+
+/* Framer registers */
+#define	FRM_CFG		0x400
+#define	FRM_STAT	0x404
+#define	FRM_INT_EN	0x410
+#define	FRM_INT_STAT	0x414
+#define	FRM_INT_CLR	0x418
+#define	FRM_WAKEUP	0x41C
+#define	FRM_CLKCTL_DONE	0x420
+#define	FRM_IE_STAT	0x430
+#define	FRM_VE_STAT	0x440
+
+/* Interface registers */
+#define	INTF_CFG	0x600
+#define	INTF_STAT	0x604
+#define	INTF_INT_EN	0x610
+#define	INTF_INT_STAT	0x614
+#define	INTF_INT_CLR	0x618
+#define	INTF_IE_STAT	0x630
+#define	INTF_VE_STAT	0x640
+
+/* Interrupt status bits */
+#define	MGR_INT_TX_NACKED_2	BIT(25)
+#define	MGR_INT_MSG_BUF_CONTE	BIT(26)
+#define	MGR_INT_RX_MSG_RCVD	BIT(30)
+#define	MGR_INT_TX_MSG_SENT	BIT(31)
+
+/* Framer config register settings */
+#define	FRM_ACTIVE	1
+#define	CLK_GEAR	7
+#define	ROOT_FREQ	11
+#define	REF_CLK_GEAR	15
+#define	INTR_WAKE	19
+
+#define SLIM_MSG_ASM_FIRST_WORD(l, mt, mc, dt, ad) \
+		((l) | ((mt) << 5) | ((mc) << 8) | ((dt) << 15) | ((ad) << 16))
+
+#define SLIM_ROOT_FREQ 24576000
+
+/* MAX message size over control channel */
+#define SLIM_MSGQ_BUF_LEN	40
+#define QCOM_TX_MSGS 2
+#define QCOM_RX_MSGS	8
+#define QCOM_BUF_ALLOC_RETRIES	10
+
+#define CFG_PORT(r, v) ((v) ? CFG_PORT_V2(r) : CFG_PORT_V1(r))
+
+/* V2 Component registers */
+#define CFG_PORT_V2(r) ((r ## _V2))
+#define	COMP_CFG_V2		4
+#define	COMP_TRUST_CFG_V2	0x3000
+
+/* V1 Component registers */
+#define CFG_PORT_V1(r) ((r ## _V1))
+#define	COMP_CFG_V1		0
+#define	COMP_TRUST_CFG_V1	0x14
+
+/* Resource group info for manager, and non-ported generic device-components */
+#define EE_MGR_RSC_GRP	(1 << 10)
+#define EE_NGD_2	(2 << 6)
+#define EE_NGD_1	0
+
+struct slim_ctrl_buf {
+	void		*base;
+	phys_addr_t	phy;
+	spinlock_t	lock;
+	int		head;
+	int		tail;
+	int		sl_sz;
+	int		n;
+};
+
+struct qcom_slim_ctrl {
+	struct slim_controller  ctrl;
+	struct slim_framer	framer;
+	struct device		*dev;
+	void __iomem		*base;
+	void __iomem		*slew_reg;
+
+	struct slim_ctrl_buf	rx;
+	struct slim_ctrl_buf	tx;
+
+	struct completion	**wr_comp;
+	int			irq;
+	struct workqueue_struct *rxwq;
+	struct work_struct	wd;
+	struct clk		*rclk;
+	struct clk		*hclk;
+};
+
+static void qcom_slim_queue_tx(struct qcom_slim_ctrl *ctrl, void *buf,
+			       u8 len, u32 tx_reg)
+{
+	int count = (len + 3) >> 2;
+
+	__iowrite32_copy(ctrl->base + tx_reg, buf, count);
+
+	/* Ensure Oder of subsequent writes */
+	mb();
+}
+
+static void *slim_alloc_rxbuf(struct qcom_slim_ctrl *ctrl)
+{
+	unsigned long flags;
+	int idx;
+
+	spin_lock_irqsave(&ctrl->rx.lock, flags);
+	if ((ctrl->rx.tail + 1) % ctrl->rx.n == ctrl->rx.head) {
+		spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+		dev_err(ctrl->dev, "RX QUEUE full!");
+		return NULL;
+	}
+	idx = ctrl->rx.tail;
+	ctrl->rx.tail = (ctrl->rx.tail + 1) % ctrl->rx.n;
+	spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+
+	return ctrl->rx.base + (idx * ctrl->rx.sl_sz);
+}
+
+void slim_ack_txn(struct qcom_slim_ctrl *ctrl, int err)
+{
+	struct completion *comp;
+	unsigned long flags;
+	int idx;
+
+	spin_lock_irqsave(&ctrl->tx.lock, flags);
+	idx = ctrl->tx.head;
+	ctrl->tx.head = (ctrl->tx.head + 1) % ctrl->tx.n;
+	spin_unlock_irqrestore(&ctrl->tx.lock, flags);
+
+	comp = ctrl->wr_comp[idx];
+	ctrl->wr_comp[idx] = NULL;
+
+	complete(comp);
+}
+
+static irqreturn_t qcom_slim_handle_tx_irq(struct qcom_slim_ctrl *ctrl,
+					   u32 stat)
+{
+	int err = 0;
+
+	if (stat & MGR_INT_TX_MSG_SENT)
+		writel_relaxed(MGR_INT_TX_MSG_SENT,
+			       ctrl->base + MGR_INT_CLR);
+
+	if (stat & MGR_INT_TX_NACKED_2) {
+		u32 mgr_stat = readl_relaxed(ctrl->base + MGR_STATUS);
+		u32 mgr_ie_stat = readl_relaxed(ctrl->base + MGR_IE_STAT);
+		u32 frm_stat = readl_relaxed(ctrl->base + FRM_STAT);
+		u32 frm_cfg = readl_relaxed(ctrl->base + FRM_CFG);
+		u32 frm_intr_stat = readl_relaxed(ctrl->base + FRM_INT_STAT);
+		u32 frm_ie_stat = readl_relaxed(ctrl->base + FRM_IE_STAT);
+		u32 intf_stat = readl_relaxed(ctrl->base + INTF_STAT);
+		u32 intf_intr_stat = readl_relaxed(ctrl->base + INTF_INT_STAT);
+		u32 intf_ie_stat = readl_relaxed(ctrl->base + INTF_IE_STAT);
+
+		writel_relaxed(MGR_INT_TX_NACKED_2, ctrl->base + MGR_INT_CLR);
+
+		dev_err(ctrl->dev, "TX Nack MGR:int:0x%x, stat:0x%x\n",
+			stat, mgr_stat);
+		dev_err(ctrl->dev, "TX Nack MGR:ie:0x%x\n", mgr_ie_stat);
+		dev_err(ctrl->dev, "TX Nack FRM:int:0x%x, stat:0x%x\n",
+			frm_intr_stat, frm_stat);
+		dev_err(ctrl->dev, "TX Nack FRM:cfg:0x%x, ie:0x%x\n",
+			frm_cfg, frm_ie_stat);
+		dev_err(ctrl->dev, "TX Nack INTF:intr:0x%x, stat:0x%x\n",
+			intf_intr_stat, intf_stat);
+		dev_err(ctrl->dev, "TX Nack INTF:ie:0x%x\n",
+			intf_ie_stat);
+		err = -ENOTCONN;
+	}
+
+	slim_ack_txn(ctrl, err);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t qcom_slim_handle_rx_irq(struct qcom_slim_ctrl *ctrl,
+					   u32 stat)
+{
+	u32 *rx_buf, pkt[10];
+	bool q_rx = false;
+	u8 la, *buf, mc, mt, len, *b = (u8 *)&pkt[0];
+	u16 ele;
+
+	pkt[0] = readl_relaxed(ctrl->base + MGR_RX_MSG);
+	mt = SLIM_HEADER_GET_MT(b[0]);
+	len = SLIM_HEADER_GET_RL(b[0]);
+	mc = SLIM_HEADER_GET_MC(b[1]);
+
+	/*
+	 * this message cannot be handled by ISR, so
+	 * let work-queue handle it
+	 */
+	if (mt == SLIM_MSG_MT_CORE &&
+		mc == SLIM_MSG_MC_REPORT_PRESENT)
+		rx_buf = (u32 *)slim_alloc_rxbuf(ctrl);
+	else
+		rx_buf = pkt;
+
+	if (rx_buf == NULL) {
+		dev_err(ctrl->dev, "dropping RX:0x%x due to RX full\n",
+					pkt[0]);
+		goto rx_ret_irq;
+	}
+
+	rx_buf[0] = pkt[0];
+	__ioread32_copy(rx_buf + 1, ctrl->base + MGR_RX_MSG + 4,
+			DIV_ROUND_UP(len, 4));
+
+	switch (mc) {
+
+	case SLIM_MSG_MC_REPORT_PRESENT:
+		q_rx = true;
+		break;
+	case SLIM_MSG_MC_REPLY_INFORMATION:
+	case SLIM_MSG_MC_REPLY_VALUE:
+		slim_msg_response(&ctrl->ctrl, (u8 *)(rx_buf + 1),
+				  (u8)(*rx_buf >> 24), (len - 4));
+		break;
+	case SLIM_MSG_MC_REPORT_INFORMATION:
+		buf = (u8 *)rx_buf;
+		la = buf[2];
+		ele = (u16)buf[4] << 4;
+
+		ele |= ((buf[3] & 0xf0) >> 4);
+		/*
+		 * report information is most likely loss of
+		 * sync or collision detected in data slots
+		 */
+		dev_info(ctrl->dev, "LA:%d report inf ele:0x%x\n",
+			 la, ele);
+		break;
+	default:
+		dev_err(ctrl->dev, "unsupported MC,%x MT:%x\n",
+			mc, mt);
+		break;
+	}
+rx_ret_irq:
+	writel(MGR_INT_RX_MSG_RCVD, ctrl->base +
+		       MGR_INT_CLR);
+	if (q_rx)
+		queue_work(ctrl->rxwq, &ctrl->wd);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t qcom_slim_interrupt(int irq, void *d)
+{
+	struct qcom_slim_ctrl *ctrl = d;
+	u32 stat = readl_relaxed(ctrl->base + MGR_INT_STAT);
+	int ret = IRQ_NONE;
+
+	if (stat & MGR_INT_TX_MSG_SENT || stat & MGR_INT_TX_NACKED_2)
+		ret = qcom_slim_handle_tx_irq(ctrl, stat);
+
+	if (stat & MGR_INT_RX_MSG_RCVD)
+		ret = qcom_slim_handle_rx_irq(ctrl, stat);
+
+	return ret;
+}
+
+void *slim_alloc_txbuf(struct qcom_slim_ctrl *ctrl, struct slim_msg_txn *txn,
+		       struct completion *done)
+{
+	unsigned long flags;
+	int idx;
+
+	spin_lock_irqsave(&ctrl->tx.lock, flags);
+	if (((ctrl->tx.head + 1) % ctrl->tx.n) == ctrl->tx.tail) {
+		spin_unlock_irqrestore(&ctrl->tx.lock, flags);
+		dev_err(ctrl->dev, "controller TX buf unavailable");
+		return NULL;
+	}
+	idx = ctrl->tx.tail;
+	ctrl->wr_comp[idx] = done;
+	ctrl->tx.tail = (ctrl->tx.tail + 1) % ctrl->tx.n;
+
+	spin_unlock_irqrestore(&ctrl->tx.lock, flags);
+
+	return ctrl->tx.base + (idx * ctrl->tx.sl_sz);
+}
+
+
+static int qcom_xfer_msg(struct slim_controller *sctrl,
+			 struct slim_msg_txn *txn)
+{
+	struct qcom_slim_ctrl *ctrl = dev_get_drvdata(sctrl->dev);
+	DECLARE_COMPLETION_ONSTACK(done);
+	void *pbuf = slim_alloc_txbuf(ctrl, txn, &done);
+	unsigned long ms = txn->rl + HZ;
+	u8 *puc;
+	int ret = 0, timeout, retries = QCOM_BUF_ALLOC_RETRIES;
+	u8 la = txn->la;
+	u32 *head;
+	/* HW expects length field to be excluded */
+	txn->rl--;
+
+	/* spin till buffer is made available */
+	if (!pbuf) {
+		while (retries--) {
+			usleep_range(10000, 15000);
+			pbuf = slim_alloc_txbuf(ctrl, txn, &done);
+			if (pbuf)
+				break;
+		}
+	}
+
+	if (!retries && !pbuf)
+		return -ENOMEM;
+
+	puc = (u8 *)pbuf;
+	head = (u32 *)pbuf;
+
+	if (txn->dt == SLIM_MSG_DEST_LOGICALADDR)
+		*head = SLIM_MSG_ASM_FIRST_WORD(txn->rl, txn->mt, txn->mc, 0,
+						la);
+	else
+		*head = SLIM_MSG_ASM_FIRST_WORD(txn->rl, txn->mt, txn->mc, 1,
+						la);
+
+	if (txn->dt == SLIM_MSG_DEST_LOGICALADDR)
+		puc += 3;
+	else
+		puc += 2;
+
+	if (txn->mt == SLIM_MSG_MT_CORE && slim_tid_txn(txn->mt, txn->mc))
+		*(puc++) = txn->tid;
+
+	if ((txn->mt == SLIM_MSG_MT_CORE) &&
+		((txn->mc >= SLIM_MSG_MC_REQUEST_INFORMATION &&
+		txn->mc <= SLIM_MSG_MC_REPORT_INFORMATION) ||
+		(txn->mc >= SLIM_MSG_MC_REQUEST_VALUE &&
+		 txn->mc <= SLIM_MSG_MC_CHANGE_VALUE))) {
+		*(puc++) = (txn->ec & 0xFF);
+		*(puc++) = (txn->ec >> 8) & 0xFF;
+	}
+
+	if (txn->msg && txn->msg->wbuf)
+		memcpy(puc, txn->msg->wbuf, txn->msg->num_bytes);
+
+	qcom_slim_queue_tx(ctrl, head, txn->rl, MGR_TX_MSG);
+	timeout = wait_for_completion_timeout(&done, msecs_to_jiffies(ms));
+
+	if (!timeout) {
+		dev_err(ctrl->dev, "TX timed out:MC:0x%x,mt:0x%x", txn->mc,
+					txn->mt);
+		ret = -ETIMEDOUT;
+	}
+
+	return ret;
+
+}
+
+static int qcom_set_laddr(struct slim_controller *sctrl,
+				struct slim_eaddr *ead, u8 laddr)
+{
+	struct qcom_slim_ctrl *ctrl = dev_get_drvdata(sctrl->dev);
+	struct {
+		__be16 manf_id;
+		__be16 prod_code;
+		u8 dev_index;
+		u8 instance;
+		u8 laddr;
+	} __packed p;
+	struct slim_val_inf msg = {0};
+	DEFINE_SLIM_EDEST_TXN(txn, SLIM_MSG_MC_ASSIGN_LOGICAL_ADDRESS,
+			      10, laddr, &msg);
+	int ret;
+
+	p.manf_id = cpu_to_be16(ead->manf_id);
+	p.prod_code = cpu_to_be16(ead->prod_code);
+	p.dev_index = ead->dev_index;
+	p.instance = ead->instance;
+	p.laddr = laddr;
+
+	msg.wbuf = (void *)&p;
+	msg.num_bytes = 7;
+	ret = slim_do_transfer(&ctrl->ctrl, &txn);
+
+	if (ret)
+		dev_err(ctrl->dev, "set LA:0x%x failed:ret:%d\n",
+				  laddr, ret);
+	return ret;
+}
+
+static int slim_get_current_rxbuf(struct qcom_slim_ctrl *ctrl, void *buf)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctrl->rx.lock, flags);
+	if (ctrl->rx.tail == ctrl->rx.head) {
+		spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+		return -ENODATA;
+	}
+	memcpy(buf, ctrl->rx.base + (ctrl->rx.head * ctrl->rx.sl_sz),
+				ctrl->rx.sl_sz);
+
+	ctrl->rx.head = (ctrl->rx.head + 1) % ctrl->rx.n;
+	spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+
+	return 0;
+}
+
+static void qcom_slim_rxwq(struct work_struct *work)
+{
+	u8 buf[SLIM_MSGQ_BUF_LEN];
+	u8 mc, mt, len;
+	int i, ret;
+	struct qcom_slim_ctrl *ctrl = container_of(work, struct qcom_slim_ctrl,
+						 wd);
+
+	while ((slim_get_current_rxbuf(ctrl, buf)) != -ENODATA) {
+		len = SLIM_HEADER_GET_RL(buf[0]);
+		mt = SLIM_HEADER_GET_MT(buf[0]);
+		mc = SLIM_HEADER_GET_MC(buf[1]);
+		if (mt == SLIM_MSG_MT_CORE &&
+			mc == SLIM_MSG_MC_REPORT_PRESENT) {
+			u8 laddr;
+			struct slim_eaddr ea;
+			u8 e_addr[6];
+
+			for (i = 0; i < 6; i++)
+				e_addr[i] = buf[7-i];
+
+			ea.manf_id = (u16)(e_addr[5] << 8) | e_addr[4];
+			ea.prod_code = (u16)(e_addr[3] << 8) | e_addr[2];
+			ea.dev_index = e_addr[1];
+			ea.instance = e_addr[0];
+			ret = slim_device_report_present(&ctrl->ctrl,
+							 &ea, &laddr);
+			if (ret < 0)
+				dev_err(ctrl->dev, "assign laddr failed:%d\n",
+					ret);
+		} else {
+			dev_err(ctrl->dev, "unexpected message:mc:%x, mt:%x\n",
+				mc, mt);
+		}
+	}
+}
+
+static void qcom_slim_prg_slew(struct platform_device *pdev,
+				struct qcom_slim_ctrl *ctrl)
+{
+	struct resource	*slew_mem;
+
+	if (!ctrl->slew_reg) {
+		/* SLEW RATE register for this slimbus */
+		slew_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+				"slew");
+		ctrl->slew_reg = devm_ioremap(&pdev->dev, slew_mem->start,
+				resource_size(slew_mem));
+		if (!ctrl->slew_reg)
+			return;
+	}
+
+	writel_relaxed(1, ctrl->slew_reg);
+	/* Make sure slimbus-slew rate enabling goes through */
+	wmb();
+}
+
+static int qcom_slim_probe(struct platform_device *pdev)
+{
+	struct qcom_slim_ctrl *ctrl;
+	struct slim_controller *sctrl;
+	struct resource *slim_mem;
+	int ret, ver;
+
+	ctrl = devm_kzalloc(&pdev->dev, sizeof(*ctrl), GFP_KERNEL);
+	if (!ctrl)
+		return -ENOMEM;
+
+	ctrl->hclk = devm_clk_get(&pdev->dev, "iface");
+	if (IS_ERR(ctrl->hclk))
+		return PTR_ERR(ctrl->hclk);
+
+	ctrl->rclk = devm_clk_get(&pdev->dev, "core");
+	if (IS_ERR(ctrl->rclk))
+		return PTR_ERR(ctrl->rclk);
+
+	ret = clk_set_rate(ctrl->rclk, SLIM_ROOT_FREQ);
+	if (ret) {
+		dev_err(&pdev->dev, "ref-clock set-rate failed:%d\n", ret);
+		return ret;
+	}
+
+	ctrl->irq = platform_get_irq(pdev, 0);
+	if (!ctrl->irq) {
+		dev_err(&pdev->dev, "no slimbus IRQ\n");
+		return -ENODEV;
+	}
+
+	sctrl = &ctrl->ctrl;
+	sctrl->dev = &pdev->dev;
+	ctrl->dev = &pdev->dev;
+	platform_set_drvdata(pdev, ctrl);
+	dev_set_drvdata(ctrl->dev, ctrl);
+
+	slim_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ctrl");
+	ctrl->base = devm_ioremap_resource(ctrl->dev, slim_mem);
+	if (!ctrl->base) {
+		dev_err(&pdev->dev, "IOremap failed\n");
+		return -ENOMEM;
+	}
+
+	sctrl->set_laddr = qcom_set_laddr;
+	sctrl->xfer_msg = qcom_xfer_msg;
+	ctrl->tx.n = QCOM_TX_MSGS;
+	ctrl->tx.sl_sz = SLIM_MSGQ_BUF_LEN;
+	ctrl->rx.n = QCOM_RX_MSGS;
+	ctrl->rx.sl_sz = SLIM_MSGQ_BUF_LEN;
+	ctrl->wr_comp = kzalloc(sizeof(struct completion *) * QCOM_TX_MSGS,
+				GFP_KERNEL);
+	if (!ctrl->wr_comp)
+		return -ENOMEM;
+
+	spin_lock_init(&ctrl->rx.lock);
+	spin_lock_init(&ctrl->tx.lock);
+	INIT_WORK(&ctrl->wd, qcom_slim_rxwq);
+	ctrl->rxwq = create_singlethread_workqueue("qcom_slim_rx");
+	if (!ctrl->rxwq) {
+		dev_err(ctrl->dev, "Failed to start Rx WQ\n");
+		return -ENOMEM;
+	}
+
+	ctrl->framer.rootfreq = SLIM_ROOT_FREQ / 8;
+	ctrl->framer.superfreq =
+		ctrl->framer.rootfreq / SLIM_CL_PER_SUPERFRAME_DIV8;
+	sctrl->a_framer = &ctrl->framer;
+	sctrl->clkgear = SLIM_MAX_CLK_GEAR;
+
+	qcom_slim_prg_slew(pdev, ctrl);
+
+	ret = devm_request_irq(&pdev->dev, ctrl->irq, qcom_slim_interrupt,
+				IRQF_TRIGGER_HIGH, "qcom_slim_irq", ctrl);
+	if (ret) {
+		dev_err(&pdev->dev, "request IRQ failed\n");
+		goto err_request_irq_failed;
+	}
+
+	ret = clk_prepare_enable(ctrl->hclk);
+	if (ret)
+		goto err_hclk_enable_failed;
+
+	ret = clk_prepare_enable(ctrl->rclk);
+	if (ret)
+		goto err_rclk_enable_failed;
+
+	ctrl->tx.base = dmam_alloc_coherent(&pdev->dev,
+					   (ctrl->tx.sl_sz * ctrl->tx.n),
+					   &ctrl->tx.phy, GFP_KERNEL);
+	if (!ctrl->tx.base) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	ctrl->rx.base = dmam_alloc_coherent(&pdev->dev,
+					   (ctrl->rx.sl_sz * ctrl->rx.n),
+					   &ctrl->rx.phy, GFP_KERNEL);
+	if (!ctrl->rx.base) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	/* Register with framework before enabling frame, clock */
+	ret = slim_register_controller(&ctrl->ctrl);
+	if (ret) {
+		dev_err(ctrl->dev, "error adding controller\n");
+		goto err;
+	}
+
+	ver = readl_relaxed(ctrl->base);
+	/* Version info in 16 MSbits */
+	ver >>= 16;
+	/* Component register initialization */
+	writel(1, ctrl->base + CFG_PORT(COMP_CFG, ver));
+	writel((EE_MGR_RSC_GRP | EE_NGD_2 | EE_NGD_1),
+				ctrl->base + CFG_PORT(COMP_TRUST_CFG, ver));
+
+	writel((MGR_INT_TX_NACKED_2 |
+			MGR_INT_MSG_BUF_CONTE | MGR_INT_RX_MSG_RCVD |
+			MGR_INT_TX_MSG_SENT), ctrl->base + MGR_INT_EN);
+	writel(1, ctrl->base + MGR_CFG);
+	/* Framer register initialization */
+	writel((1 << INTR_WAKE) | (0xA << REF_CLK_GEAR) |
+		(0xA << CLK_GEAR) | (1 << ROOT_FREQ) | (1 << FRM_ACTIVE) | 1,
+		ctrl->base + FRM_CFG);
+	writel(MGR_CFG_ENABLE, ctrl->base + MGR_CFG);
+	writel(1, ctrl->base + INTF_CFG);
+	writel(1, ctrl->base + CFG_PORT(COMP_CFG, ver));
+
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_autosuspend_delay(&pdev->dev, QCOM_SLIM_AUTOSUSPEND);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_mark_last_busy(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	dev_dbg(ctrl->dev, "QCOM SB controller is up:ver:0x%x!\n", ver);
+	return 0;
+
+err:
+	clk_disable_unprepare(ctrl->rclk);
+err_rclk_enable_failed:
+	clk_disable_unprepare(ctrl->hclk);
+err_hclk_enable_failed:
+err_request_irq_failed:
+	destroy_workqueue(ctrl->rxwq);
+	return ret;
+}
+
+static int qcom_slim_remove(struct platform_device *pdev)
+{
+	struct qcom_slim_ctrl *ctrl = platform_get_drvdata(pdev);
+
+	disable_irq(ctrl->irq);
+	clk_disable_unprepare(ctrl->hclk);
+	clk_disable_unprepare(ctrl->rclk);
+	slim_unregister_controller(&ctrl->ctrl);
+	destroy_workqueue(ctrl->rxwq);
+	return 0;
+}
+
+static const struct dev_pm_ops qcom_slim_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(qcom_slim_suspend, qcom_slim_resume)
+	SET_RUNTIME_PM_OPS(
+			   qcom_slim_runtime_suspend,
+			   qcom_slim_runtime_resume,
+			   NULL
+	)
+};
+
+static const struct of_device_id qcom_slim_dt_match[] = {
+	{ .compatible = "qcom,slim", },
+	{ .compatible = "qcom,apq8064-slim", },
+	{}
+};
+
+static struct platform_driver qcom_slim_driver = {
+	.probe = qcom_slim_probe,
+	.remove = qcom_slim_remove,
+	.driver	= {
+		.name = "qcom_slim_ctrl",
+		.of_match_table = qcom_slim_dt_match,
+	},
+};
+module_platform_driver(qcom_slim_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Qualcomm SLIMBus Controller");