[PATCH V4 4/6] slim: qcom: Add Qualcomm Slimbus controller driver

[Sagar Dharia]

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@xxxxxxxxxxxxxx>
---
 .../devicetree/bindings/slimbus/slim-qcom-ctrl.txt |  43 ++
 drivers/slimbus/Kconfig                            |  10 +
 drivers/slimbus/Makefile                           |   1 +
 drivers/slimbus/slim-qcom-ctrl.c                   | 556 +++++++++++++++++++++
 drivers/slimbus/slim-qcom.h                        |  63 +++
 5 files changed, 673 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/slimbus/slim-qcom-ctrl.txt
 create mode 100644 drivers/slimbus/slim-qcom-ctrl.c
 create mode 100644 drivers/slimbus/slim-qcom.h

diff --git a/Documentation/devicetree/bindings/slimbus/slim-qcom-ctrl.txt b/Documentation/devicetree/bindings/slimbus/slim-qcom-ctrl.txt
new file mode 100644
index 0000000..7b6c366
--- /dev/null
+++ b/Documentation/devicetree/bindings/slimbus/slim-qcom-ctrl.txt
@@ -0,0 +1,43 @@
+Qualcomm SLIMBUS controller
+"qcom,slim-msm": This controller is used if applications processor
+	driver is controlling slimbus master component. This driver is
+	responsible for communicating with slave HW directly using
+	messaging interface, and doing data channel management.
+
+Required properties:
+
+- #address-cells - should be 4 (number of cells required to define
+		4 fields of the enumeration address for the SLIMbus
+		slave device)
+- #size-cells	- should be 0
+ - reg : Offset and length of the register region(s) for the device
+ - reg-names : Register region name(s) referenced in reg above
+	 Required register resource entries are:
+	 "slimbus_physical": Physical adderss of controller register blocks
+ - compatible : should be "qcom,slim-msm" if this is master component driver
+ - interrupts : Interrupt number used by this controller
+ - clocks : Interface and core clocks used by this slimbus controller
+ - clock-names : Required clock-name entries are:
+	"iface_clk" : Interface clock for this controller
+	"core_clk" : Interrupt for controller core's BAM
+
+Optional property:
+ - reg entry for slew rate : If slew rate control register is provided, this
+	entry should be used.
+ - reg-name for slew rate: "slimbus_slew_reg"
+
+Example:
+	slim@28080000 {
+		compatible = "qcom,slim-msm";
+		#address-cells = <4>;
+		#size-cells = <0>;
+		reg = <0x28080000 0x2000>, <0x80207C 4>;
+		reg-names = "slimbus_physical", "slimbus_slew_reg";
+		interrupts = <0 33 0>;
+		clocks = <&lcc SLIMBUS_SRC>, <&lcc AUDIO_SLIMBUS_CLK>;
+		clock-names = "iface_clk", "core_clk";
+
+		slimdev@xxxxxxxxxxxxxxx {
+			reg = <0x217 0x60 0x1 0x0>;
+		};
+	};
diff --git a/drivers/slimbus/Kconfig b/drivers/slimbus/Kconfig
index f0b118a..afe15b3 100644
--- a/drivers/slimbus/Kconfig
+++ b/drivers/slimbus/Kconfig
@@ -9,3 +9,13 @@ menuconfig SLIMBUS
 
 	  If unsure, choose N.
 
+if SLIMBUS
+config SLIM_QCOM_CTRL
+	tristate "Qualcomm Slimbus Manager Component"
+	depends on SLIMBUS
+	default n
+	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 d95a0a2..574a892 100644
--- a/drivers/slimbus/Makefile
+++ b/drivers/slimbus/Makefile
@@ -2,3 +2,4 @@
 # Makefile for kernel slimbus framework.
 #
 obj-$(CONFIG_SLIMBUS)			+= slim-core.o slim-messaging.o
+obj-$(CONFIG_SLIM_QCOM_CTRL)		+= slim-qcom-ctrl.o
diff --git a/drivers/slimbus/slim-qcom-ctrl.c b/drivers/slimbus/slim-qcom-ctrl.c
new file mode 100644
index 0000000..df20fb4
--- /dev/null
+++ b/drivers/slimbus/slim-qcom-ctrl.c
@@ -0,0 +1,556 @@
+/* Copyright (c) 2011-2016, 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/slimbus.h>
+#include "slim-qcom.h"
+
+#define MSM_SLIM_NAME	"msm_slim_ctrl"
+
+/* 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
+
+static int msm_slim_queue_tx(struct msm_slim_ctrl *dev, u32 *buf, u8 len,
+			     u32 tx_reg)
+{
+	int i;
+
+	for (i = 0; i < (len + 3) >> 2; i++) {
+		dev_dbg(dev->dev, "AHB TX data:0x%x\n", buf[i]);
+		writel_relaxed(buf[i], dev->base + tx_reg + (i * 4));
+	}
+	/* Guarantee that message is sent before returning */
+	mb();
+	return 0;
+}
+
+static irqreturn_t msm_slim_interrupt(int irq, void *d)
+{
+	struct msm_slim_ctrl *dev = d;
+	u32 stat = readl_relaxed(dev->base + MGR_INT_STAT);
+	int err = 0;
+
+	if (stat & MGR_INT_TX_MSG_SENT || stat & MGR_INT_TX_NACKED_2) {
+		if (stat & MGR_INT_TX_MSG_SENT)
+			writel_relaxed(MGR_INT_TX_MSG_SENT,
+				       dev->base + MGR_INT_CLR);
+		if (stat & MGR_INT_TX_NACKED_2) {
+			u32 mgr_stat = readl_relaxed(dev->base + MGR_STATUS);
+			u32 mgr_ie_stat = readl_relaxed(dev->base +
+							MGR_IE_STAT);
+			u32 frm_stat = readl_relaxed(dev->base + FRM_STAT);
+			u32 frm_cfg = readl_relaxed(dev->base + FRM_CFG);
+			u32 frm_intr_stat = readl_relaxed(dev->base +
+							  FRM_INT_STAT);
+			u32 frm_ie_stat = readl_relaxed(dev->base +
+							FRM_IE_STAT);
+			u32 intf_stat = readl_relaxed(dev->base + INTF_STAT);
+			u32 intf_intr_stat = readl_relaxed(dev->base +
+							   INTF_INT_STAT);
+			u32 intf_ie_stat = readl_relaxed(dev->base +
+							 INTF_IE_STAT);
+
+			writel_relaxed(MGR_INT_TX_NACKED_2, dev->base +
+				       MGR_INT_CLR);
+			dev_err(dev->dev, "TX Nack MGR:int:0x%x, stat:0x%x\n",
+				stat, mgr_stat);
+			dev_err(dev->dev, "TX Nack MGR:ie:0x%x\n", mgr_ie_stat);
+			dev_err(dev->dev, "TX Nack FRM:int:0x%x, stat:0x%x\n",
+				frm_intr_stat, frm_stat);
+			dev_err(dev->dev, "TX Nack FRM:cfg:0x%x, ie:0x%x\n",
+				frm_cfg, frm_ie_stat);
+			dev_err(dev->dev, "TX Nack INTF:intr:0x%x, stat:0x%x\n",
+				intf_intr_stat, intf_stat);
+			dev_err(dev->dev, "TX Nack INTF:ie:0x%x\n",
+				intf_ie_stat);
+			err = -ENOTCONN;
+		}
+		/**
+		 * Guarantee that interrupt clear bit write goes through before
+		 * signalling completion/exiting ISR
+		 */
+		mb();
+		slim_return_tx(&dev->ctrl, err);
+	}
+	if (stat & MGR_INT_RX_MSG_RCVD) {
+		u8 mc, mt;
+		u8 len, i;
+		u32 *rx_buf, pkt[10];
+		bool q_rx = false;
+
+		pkt[0] = readl_relaxed(dev->base + MGR_RX_MSG);
+		mt = (pkt[0] >> 5) & 0x7;
+		mc = (pkt[0] >> 8) & 0xff;
+		len = pkt[0] & 0x1F;
+		dev_dbg(dev->dev, "RX-IRQ: MC: %x, MT: %x\n", mc, mt);
+
+		/**
+		 * 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_get_rx(&dev->ctrl);
+		else
+			rx_buf = pkt;
+
+		if (rx_buf == NULL) {
+			dev_err(dev->dev, "dropping RX:0x%x due to RX full\n",
+						pkt[0]);
+			goto rx_ret_irq;
+		}
+
+		rx_buf[0] = pkt[0];
+		for (i = 1; i < ((len + 3) >> 2); i++) {
+			rx_buf[i] = readl_relaxed(dev->base + MGR_RX_MSG +
+						(4 * i));
+			dev_dbg(dev->dev, "reading data: %x\n", rx_buf[i]);
+		}
+
+		switch (mc) {
+			u8 *buf, la;
+			u16 ele;
+
+		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(&dev->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_err(dev->dev, "LA:%d report inf ele:0x%x\n",
+				la, ele);
+			for (i = 0; i < len - 5; i++)
+				dev_err(dev->dev, "bit-mask:%x\n",
+					buf[i+5]);
+			break;
+		default:
+			dev_err(dev->dev, "unsupported MC,%x MT:%x\n",
+				mc, mt);
+			break;
+		}
+rx_ret_irq:
+		writel_relaxed(MGR_INT_RX_MSG_RCVD, dev->base +
+			       MGR_INT_CLR);
+		/**
+		 * Guarantee that CLR bit write goes through
+		 * before exiting
+		 */
+		mb();
+		if (q_rx)
+			queue_work(dev->rxwq, &dev->wd);
+	}
+	/**
+	 * All interrupts are handled: complex RX messages requiring more work
+	 * are queued to work-queue, others are handled above
+	 */
+	return IRQ_HANDLED;
+}
+
+static int msm_xfer_msg(struct slim_controller *ctrl, struct slim_msg_txn *txn,
+			void *pbuf)
+{
+	struct msm_slim_ctrl *dev = slim_get_ctrldata(ctrl);
+	DECLARE_COMPLETION_ONSTACK(done);
+	u32 *head = (u32 *)pbuf;
+	u8 *puc = (u8 *)pbuf;
+	u8 la = txn->la;
+
+	/* HW expects length field to be excluded */
+	txn->rl--;
+
+	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);
+
+	return msm_slim_queue_tx(dev, head, txn->rl, MGR_TX_MSG);
+}
+
+static int msm_set_laddr(struct slim_controller *ctrl,
+				struct slim_eaddr *ead, u8 laddr)
+{
+	struct msm_slim_ctrl *dev = slim_get_ctrldata(ctrl);
+	u8 buf[7];
+	int ret;
+	struct slim_val_inf msg = {0};
+
+	DEFINE_SLIM_EDEST_TXN(txn, SLIM_MSG_MC_ASSIGN_LOGICAL_ADDRESS,
+			      10, laddr, &msg);
+
+	/* Enumeration address */
+	buf[0] = (u8)(ead->manf_id >> 8);
+	buf[1] = (u8)(ead->manf_id & 0xFF);
+	buf[2] = (u8) (ead->prod_code >> 8);
+	buf[3] = (u8) (ead->prod_code & 0xFF);
+	buf[4] = ead->dev_index;
+	buf[5] = ead->instance;
+	/* Logical address for this EA */
+	buf[6] = laddr;
+	/**
+	 * Retries are needed since bus may lose sync when multiple devices
+	 * are coming up and reporting present
+	 */
+	msg.wbuf = buf;
+	msg.num_bytes = 7;
+
+	ret = slim_processtxn(&dev->ctrl, &txn);
+
+	if (ret)
+		dev_err(dev->dev, "set LA:0x%x failed:ret:%d\n",
+				  laddr, ret);
+	return ret;
+}
+
+static void msm_slim_rxwq(struct work_struct *work)
+{
+	u8 buf[40];
+	u8 mc, mt, len;
+	int i, ret;
+	struct msm_slim_ctrl *dev = container_of(work, struct msm_slim_ctrl,
+						 wd);
+
+	while ((slim_return_rx(&dev->ctrl, buf)) != -ENODATA) {
+		len = buf[0] & 0x1F;
+		mt = (buf[0] >> 5) & 0x7;
+		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_assign_laddr(&dev->ctrl, &ea, &laddr, false);
+			if (ret)
+				dev_err(dev->dev, "assign laddr failed:%d\n",
+					ret);
+		} else {
+			dev_err(dev->dev, "unexpected message:mc:%x, mt:%x\n",
+				mc, mt);
+
+		}
+
+	}
+}
+
+static void msm_slim_prg_slew(struct platform_device *pdev,
+				struct msm_slim_ctrl *dev)
+{
+	void __iomem *slew_reg;
+
+	/* SLEW RATE register for this slimbus */
+	dev->slew_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+						"slimbus_slew_reg");
+	if (!dev->slew_mem) {
+		dev_warn(&pdev->dev, "no slimbus slew resource\n");
+		return;
+	}
+
+	slew_reg = devm_ioremap(&pdev->dev, dev->slew_mem->start,
+				resource_size(dev->slew_mem));
+	if (!slew_reg) {
+		dev_err(dev->dev, "slew register mapping failed");
+		release_mem_region(dev->slew_mem->start,
+					resource_size(dev->slew_mem));
+		dev->slew_mem = NULL;
+		return;
+	}
+	writel_relaxed(1, slew_reg);
+	/* Make sure slimbus-slew rate enabling goes through */
+	wmb();
+}
+
+static int msm_slim_probe(struct platform_device *pdev)
+{
+	struct msm_slim_ctrl *dev;
+	struct resource *slim_mem;
+	struct resource *irq;
+	struct clk *hclk, *rclk;
+	int ret;
+
+	hclk = devm_clk_get(&pdev->dev, "iface_clk");
+	if (IS_ERR(hclk))
+		return PTR_ERR(hclk);
+
+	rclk = devm_clk_get(&pdev->dev, "core_clk");
+	if (IS_ERR(rclk)) {
+		/* unlikely that this is probe-defer */
+		dev_err(&pdev->dev, "rclk get failed:%ld\n", PTR_ERR(rclk));
+		return PTR_ERR(rclk);
+	}
+
+	ret = clk_set_rate(rclk, SLIM_ROOT_FREQ);
+	if (ret) {
+		dev_err(&pdev->dev, "ref-clock set-rate failed:%d\n", ret);
+		return ret;
+	}
+
+	slim_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+						"slimbus_physical");
+	if (!slim_mem) {
+		dev_err(&pdev->dev, "no slimbus physical memory resource\n");
+		return -ENODEV;
+	}
+
+	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!irq) {
+		dev_err(&pdev->dev, "no slimbus IRQ resource\n");
+		return -ENODEV;
+	}
+
+	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+
+	dev->hclk = hclk;
+	dev->rclk = rclk;
+
+	dev->dev = &pdev->dev;
+	platform_set_drvdata(pdev, dev);
+	slim_set_ctrldata(&dev->ctrl, dev);
+	dev->base = devm_ioremap(dev->dev, slim_mem->start,
+				 resource_size(slim_mem));
+	if (!dev->base) {
+		dev_err(&pdev->dev, "IOremap failed\n");
+		return -ENOMEM;
+	}
+
+	dev->ctrl.set_laddr = msm_set_laddr;
+	dev->ctrl.xfer_msg = msm_xfer_msg;
+	dev->ctrl.tx.n = MSM_TX_MSGS;
+	dev->ctrl.rx.n = MSM_RX_MSGS;
+	dev->ctrl.tx.sl_sz = SLIM_MSGQ_BUF_LEN;
+	dev->ctrl.rx.sl_sz = SLIM_MSGQ_BUF_LEN;
+
+	dev->irq = irq->start;
+
+	INIT_WORK(&dev->wd, msm_slim_rxwq);
+	dev->rxwq = create_singlethread_workqueue("msm_slim_rx");
+	if (!dev->rxwq) {
+		dev_err(dev->dev, "Failed to start Rx WQ\n");
+		return -ENOMEM;
+	}
+
+	dev->framer.rootfreq = SLIM_ROOT_FREQ >> 3;
+	dev->framer.superfreq =
+		dev->framer.rootfreq / SLIM_CL_PER_SUPERFRAME_DIV8;
+	dev->ctrl.a_framer = &dev->framer;
+	dev->ctrl.clkgear = SLIM_MAX_CLK_GEAR;
+	dev->ctrl.dev.parent = &pdev->dev;
+	dev->ctrl.dev.of_node = pdev->dev.of_node;
+
+	msm_slim_prg_slew(pdev, dev);
+
+	ret = devm_request_irq(&pdev->dev, dev->irq, msm_slim_interrupt,
+				IRQF_TRIGGER_HIGH, "msm_slim_irq", dev);
+	if (ret) {
+		dev_err(&pdev->dev, "request IRQ failed\n");
+		goto err_request_irq_failed;
+	}
+
+	ret = clk_prepare_enable(hclk);
+	if (ret)
+		goto err_hclk_enable_failed;
+
+	ret = clk_prepare_enable(rclk);
+	if (ret)
+		goto err_rclk_enable_failed;
+
+	/* Register with framework before enabling frame, clock */
+	ret = slim_register_controller(&dev->ctrl);
+	if (ret) {
+		dev_err(dev->dev, "error adding controller\n");
+		goto err_ctrl_failed;
+	}
+
+	dev->ver = readl_relaxed(dev->base);
+	/* Version info in 16 MSbits */
+	dev->ver >>= 16;
+	/* Component register initialization */
+	writel_relaxed(1, dev->base + CFG_PORT(COMP_CFG, dev->ver));
+	writel_relaxed((EE_MGR_RSC_GRP | EE_NGD_2 | EE_NGD_1),
+				dev->base + CFG_PORT(COMP_TRUST_CFG, dev->ver));
+
+	writel_relaxed((MGR_INT_TX_NACKED_2 |
+			MGR_INT_MSG_BUF_CONTE | MGR_INT_RX_MSG_RCVD |
+			MGR_INT_TX_MSG_SENT), dev->base + MGR_INT_EN);
+	writel_relaxed(1, dev->base + MGR_CFG);
+	/*
+	 * Framer registers are beyond 1K memory region after Manager and/or
+	 * component registers. Make sure those writes are ordered
+	 * before framer register writes
+	 */
+	wmb();
+
+	/* Framer register initialization */
+	writel_relaxed((1 << INTR_WAKE) | (0xA << REF_CLK_GEAR) |
+		(0xA << CLK_GEAR) | (1 << ROOT_FREQ) | (1 << FRM_ACTIVE) | 1,
+		dev->base + FRM_CFG);
+	/*
+	 * Make sure that framer wake-up and enabling writes go through
+	 * before any other component is enabled. Framer is responsible for
+	 * clocking the bus and enabling framer first will ensure that other
+	 * devices can report presence when they are enabled
+	 */
+	mb();
+
+	writel_relaxed(MGR_CFG_ENABLE, dev->base + MGR_CFG);
+	/*
+	 * Make sure that manager-enable is written through before interface
+	 * device is enabled
+	 */
+	mb();
+	writel_relaxed(1, dev->base + INTF_CFG);
+	/*
+	 * Make sure that interface-enable is written through before enabling
+	 * ported generic device inside MSM manager
+	 */
+	mb();
+
+	writel_relaxed(1, dev->base + CFG_PORT(COMP_CFG, dev->ver));
+	/*
+	 * Make sure that all writes have gone through before exiting this
+	 * function
+	 */
+	mb();
+
+	dev_dbg(dev->dev, "MSM SB controller is up:ver:0x%x!\n", dev->ver);
+	return 0;
+
+err_ctrl_failed:
+	clk_disable_unprepare(dev->rclk);
+err_rclk_enable_failed:
+	clk_disable_unprepare(dev->hclk);
+err_hclk_enable_failed:
+err_request_irq_failed:
+	destroy_workqueue(dev->rxwq);
+	return ret;
+}
+
+static int msm_slim_remove(struct platform_device *pdev)
+{
+	struct msm_slim_ctrl *dev = platform_get_drvdata(pdev);
+
+	slim_del_controller(&dev->ctrl);
+	destroy_workqueue(dev->rxwq);
+	return 0;
+}
+
+static const struct of_device_id msm_slim_dt_match[] = {
+	{
+		.compatible = "qcom,slim-msm",
+	},
+	{}
+};
+
+static struct platform_driver msm_slim_driver = {
+	.probe = msm_slim_probe,
+	.remove = msm_slim_remove,
+	.driver	= {
+		.name = MSM_SLIM_NAME,
+		.owner = THIS_MODULE,
+		.of_match_table = msm_slim_dt_match,
+	},
+};
+module_platform_driver(msm_slim_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION("0.1");
+MODULE_DESCRIPTION("Qualcomm Slimbus controller");
+MODULE_ALIAS("platform:qcom-slim");
diff --git a/drivers/slimbus/slim-qcom.h b/drivers/slimbus/slim-qcom.h
new file mode 100644
index 0000000..0ad59c3
--- /dev/null
+++ b/drivers/slimbus/slim-qcom.h
@@ -0,0 +1,63 @@
+/* Copyright (c) 2011-2016, 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.
+ */
+
+#ifndef _SLIM_QCOM_H
+#define _SLIM_QCOM_H
+
+#include <linux/irq.h>
+#include <linux/workqueue.h>
+
+#define QC_MFGID_LSB	0x2
+#define QC_MFGID_MSB	0x17
+
+#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 MSM_TX_MSGS 2
+#define MSM_RX_MSGS	8
+
+#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 msm_slim_ctrl {
+	struct slim_controller  ctrl;
+	struct slim_framer	framer;
+	struct device		*dev;
+	void __iomem		*base;
+	struct resource		*slew_mem;
+	int			irq;
+	struct workqueue_struct *rxwq;
+	struct work_struct	wd;
+	struct clk		*rclk;
+	struct clk		*hclk;
+	u32			ver;
+};
+
+#endif
-- 
1.8.2.1