diff mbox

[1/2] add new platform driver for PCI RC

Message ID 5ee7247815c9e5ca230af5397fd61e03d2c552aa.1448364079.git.jpinto@synopsys.com
State Superseded
Headers show

Commit Message

Joao Pinto Nov. 24, 2015, 11:44 a.m. UTC
This patch adds a new driver that will be the reference platform driver for all
PCIe RC IP Protoyping Kits based on ARC SDP. This patch is composed by:

-Changes to pcie-designware driver adds a function that enables the feature
of starting the LTSSM (Link Train Status State) used by the new driver
-MAINTAINERS file was updated to include the new driver
-Documentation/devicetree/bindings/pci was updated to include the new driver
documentation

Signed-off-by: Joao Pinto <jpinto@synopsys.com>
---
 .../devicetree/bindings/pci/pcie-snpsdev.txt       |  28 ++
 MAINTAINERS                                        |   7 +
 drivers/pci/host/Kconfig                           |   5 +
 drivers/pci/host/Makefile                          |   1 +
 drivers/pci/host/pcie-designware.c                 |   9 +
 drivers/pci/host/pcie-designware.h                 |   1 +
 drivers/pci/host/pcie-snpsdev.c                    | 342 +++++++++++++++++++++
 7 files changed, 393 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/pcie-snpsdev.txt
 create mode 100644 drivers/pci/host/pcie-snpsdev.c

Comments

kernel test robot Nov. 24, 2015, 12:15 p.m. UTC | #1
Hi Joao,

[auto build test ERROR on arc/for-next]
[also build test ERROR on v4.4-rc2 next-20151124]

url:    https://github.com/0day-ci/linux/commits/Joao-Pinto/add-new-platform-driver-for-PCI-RC/20151124-194755
base:   https://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc for-next
config: i386-allmodconfig (attached as .config)
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All errors (new ones prefixed by >>):

   drivers/pci/host/pcie-designware.c: In function 'dw_pcie_host_init':
   drivers/pci/host/pcie-designware.c:555:7: error: implicit declaration of function 'pci_has_flag' [-Werror=implicit-function-declaration]
     if (!pci_has_flag(PCI_PROBE_ONLY)) {
          ^
   drivers/pci/host/pcie-designware.c:555:20: error: 'PCI_PROBE_ONLY' undeclared (first use in this function)
     if (!pci_has_flag(PCI_PROBE_ONLY)) {
                       ^
   drivers/pci/host/pcie-designware.c:555:20: note: each undeclared identifier is reported only once for each function it appears in
   drivers/pci/host/pcie-designware.c: In function 'dw_pcie_link_retrain':
>> drivers/pci/host/pcie-designware.c:713:23: error: 'LINK_CONTROL_LINK_STATUS_REG' undeclared (first use in this function)
     dw_pcie_readl_rc(pp, LINK_CONTROL_LINK_STATUS_REG, &val);
                          ^
>> drivers/pci/host/pcie-designware.c:714:14: error: 'PCIE_RETRAIN_LINK_MASK' undeclared (first use in this function)
     val = val | PCIE_RETRAIN_LINK_MASK;
                 ^
   cc1: some warnings being treated as errors

vim +/LINK_CONTROL_LINK_STATUS_REG +713 drivers/pci/host/pcie-designware.c

   549	
   550	#ifdef CONFIG_ARM
   551		/* support old dtbs that incorrectly describe IRQs */
   552		pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
   553	#endif
   554	
 > 555		if (!pci_has_flag(PCI_PROBE_ONLY)) {
   556			pci_bus_size_bridges(bus);
   557			pci_bus_assign_resources(bus);
   558	
   559			list_for_each_entry(child, &bus->children, node)
   560				pcie_bus_configure_settings(child);
   561		}
   562	
   563		pci_bus_add_devices(bus);
   564		return 0;
   565	}
   566	
   567	static int dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
   568			u32 devfn, int where, int size, u32 *val)
   569	{
   570		int ret, type;
   571		u32 busdev, cfg_size;
   572		u64 cpu_addr;
   573		void __iomem *va_cfg_base;
   574	
   575		busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
   576			 PCIE_ATU_FUNC(PCI_FUNC(devfn));
   577	
   578		if (bus->parent->number == pp->root_bus_nr) {
   579			type = PCIE_ATU_TYPE_CFG0;
   580			cpu_addr = pp->cfg0_base;
   581			cfg_size = pp->cfg0_size;
   582			va_cfg_base = pp->va_cfg0_base;
   583		} else {
   584			type = PCIE_ATU_TYPE_CFG1;
   585			cpu_addr = pp->cfg1_base;
   586			cfg_size = pp->cfg1_size;
   587			va_cfg_base = pp->va_cfg1_base;
   588		}
   589	
   590		dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
   591					  type, cpu_addr,
   592					  busdev, cfg_size);
   593		ret = dw_pcie_cfg_read(va_cfg_base + where, size, val);
   594		dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
   595					  PCIE_ATU_TYPE_IO, pp->io_base,
   596					  pp->io_bus_addr, pp->io_size);
   597	
   598		return ret;
   599	}
   600	
   601	static int dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
   602			u32 devfn, int where, int size, u32 val)
   603	{
   604		int ret, type;
   605		u32 busdev, cfg_size;
   606		u64 cpu_addr;
   607		void __iomem *va_cfg_base;
   608	
   609		busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
   610			 PCIE_ATU_FUNC(PCI_FUNC(devfn));
   611	
   612		if (bus->parent->number == pp->root_bus_nr) {
   613			type = PCIE_ATU_TYPE_CFG0;
   614			cpu_addr = pp->cfg0_base;
   615			cfg_size = pp->cfg0_size;
   616			va_cfg_base = pp->va_cfg0_base;
   617		} else {
   618			type = PCIE_ATU_TYPE_CFG1;
   619			cpu_addr = pp->cfg1_base;
   620			cfg_size = pp->cfg1_size;
   621			va_cfg_base = pp->va_cfg1_base;
   622		}
   623	
   624		dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
   625					  type, cpu_addr,
   626					  busdev, cfg_size);
   627		ret = dw_pcie_cfg_write(va_cfg_base + where, size, val);
   628		dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
   629					  PCIE_ATU_TYPE_IO, pp->io_base,
   630					  pp->io_bus_addr, pp->io_size);
   631	
   632		return ret;
   633	}
   634	
   635	static int dw_pcie_valid_config(struct pcie_port *pp,
   636					struct pci_bus *bus, int dev)
   637	{
   638		/* If there is no link, then there is no device */
   639		if (bus->number != pp->root_bus_nr) {
   640			if (!dw_pcie_link_up(pp))
   641				return 0;
   642		}
   643	
   644		/* access only one slot on each root port */
   645		if (bus->number == pp->root_bus_nr && dev > 0)
   646			return 0;
   647	
   648		/*
   649		 * do not read more than one device on the bus directly attached
   650		 * to RC's (Virtual Bridge's) DS side.
   651		 */
   652		if (bus->primary == pp->root_bus_nr && dev > 0)
   653			return 0;
   654	
   655		return 1;
   656	}
   657	
   658	static int dw_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
   659				int size, u32 *val)
   660	{
   661		struct pcie_port *pp = bus->sysdata;
   662		int ret;
   663	
   664		if (dw_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0) {
   665			*val = 0xffffffff;
   666			return PCIBIOS_DEVICE_NOT_FOUND;
   667		}
   668	
   669		if (bus->number != pp->root_bus_nr)
   670			if (pp->ops->rd_other_conf)
   671				ret = pp->ops->rd_other_conf(pp, bus, devfn,
   672							where, size, val);
   673			else
   674				ret = dw_pcie_rd_other_conf(pp, bus, devfn,
   675							where, size, val);
   676		else
   677			ret = dw_pcie_rd_own_conf(pp, where, size, val);
   678	
   679		return ret;
   680	}
   681	
   682	static int dw_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
   683				int where, int size, u32 val)
   684	{
   685		struct pcie_port *pp = bus->sysdata;
   686		int ret;
   687	
   688		if (dw_pcie_valid_config(pp, bus, PCI_SLOT(devfn)) == 0)
   689			return PCIBIOS_DEVICE_NOT_FOUND;
   690	
   691		if (bus->number != pp->root_bus_nr)
   692			if (pp->ops->wr_other_conf)
   693				ret = pp->ops->wr_other_conf(pp, bus, devfn,
   694							where, size, val);
   695			else
   696				ret = dw_pcie_wr_other_conf(pp, bus, devfn,
   697							where, size, val);
   698		else
   699			ret = dw_pcie_wr_own_conf(pp, where, size, val);
   700	
   701		return ret;
   702	}
   703	
   704	static struct pci_ops dw_pcie_ops = {
   705		.read = dw_pcie_rd_conf,
   706		.write = dw_pcie_wr_conf,
   707	};
   708	
   709	void dw_pcie_link_retrain(struct pcie_port *pp)
   710	{
   711		u32 val = 0;
   712	
 > 713		dw_pcie_readl_rc(pp, LINK_CONTROL_LINK_STATUS_REG, &val);
 > 714		val = val | PCIE_RETRAIN_LINK_MASK;
   715		dw_pcie_writel_rc(pp, val, LINK_CONTROL_LINK_STATUS_REG);
   716	}
   717	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/pci/pcie-snpsdev.txt b/Documentation/devicetree/bindings/pci/pcie-snpsdev.txt
new file mode 100644
index 0000000..b833c8f
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/pcie-snpsdev.txt
@@ -0,0 +1,28 @@ 
+Synopsys PCI RC IP Prototyping Kit
+----------------------------------
+
+This is the reference platform driver to be used in the Synopsys PCI RC IP
+Prototyping Kits.
+
+Required properties:
+- compatible: "snps,pcie-snpsdev";
+- reg:	A list of physical regions to access the device.
+- interrupts: interrupt for the device.
+- #address-cells: must be 3.
+- #size-cells: must be 2.
+
+Example configuration:
+
+	pcie: pcie@0xdffff000 {
+		#interrupt-cells = <1>;
+		compatible = "snps,pcie-snpsdev";
+		reg = <0xdffff000 0x1000>;
+		interrupts = <25>, <24>;
+		#address-cells = <3>;
+		#size-cells = <2>;
+		device_type = "pci";
+		ranges = <0x00000800 0 0xd0000000 0xd0000000 0 0x00002000
+			  0x81000000 0 0x00000000 0xde000000 0 0x00010000
+			  0x82000000 0 0xd0400000 0xd0400000 0 0x0d000000>;
+		num-lanes = <1>;
+	};
diff --git a/MAINTAINERS b/MAINTAINERS
index e9caa4b..d2e4506 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8230,6 +8230,13 @@  S:	Maintained
 F:	Documentation/devicetree/bindings/pci/hisilicon-pcie.txt
 F:	drivers/pci/host/pcie-hisi.c
 
+PCI DRIVER FOR SYNOPSYS PROTOTYPING DEVICE
+M:	Joao Pinto <jpinto@synopsys.com>
+L:	linux-pci@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/pci/pcie-snpsdev.txt
+F:	drivers/pci/host/pcie-snpsdev.c
+
 PCMCIA SUBSYSTEM
 P:	Linux PCMCIA Team
 L:	linux-pcmcia@lists.infradead.org
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index f131ba9..a874b1e 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -172,4 +172,9 @@  config PCI_HISI
 	help
 	  Say Y here if you want PCIe controller support on HiSilicon HIP05 SoC
 
+config PCIE_SNPSDEV
+	bool "Platform Driver for Synopsys Device"
+	select PCIEPORTBUS
+	select PCIE_DW
+
 endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 9d4d3c6..e422f65 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -20,3 +20,4 @@  obj-$(CONFIG_PCIE_IPROC_BCMA) += pcie-iproc-bcma.o
 obj-$(CONFIG_PCIE_ALTERA) += pcie-altera.o
 obj-$(CONFIG_PCIE_ALTERA_MSI) += pcie-altera-msi.o
 obj-$(CONFIG_PCI_HISI) += pcie-hisi.o
+obj-$(CONFIG_PCIE_SNPSDEV) += pcie-snpsdev.o
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 540f077..d9a7aa6 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -706,6 +706,15 @@  static struct pci_ops dw_pcie_ops = {
 	.write = dw_pcie_wr_conf,
 };
 
+void dw_pcie_link_retrain(struct pcie_port *pp)
+{
+	u32 val = 0;
+
+	dw_pcie_readl_rc(pp, LINK_CONTROL_LINK_STATUS_REG, &val);
+	val = val | PCIE_RETRAIN_LINK_MASK;
+	dw_pcie_writel_rc(pp, val, LINK_CONTROL_LINK_STATUS_REG);
+}
+
 void dw_pcie_setup_rc(struct pcie_port *pp)
 {
 	u32 val;
diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h
index 2356d29..249b631 100644
--- a/drivers/pci/host/pcie-designware.h
+++ b/drivers/pci/host/pcie-designware.h
@@ -79,5 +79,6 @@  void dw_pcie_msi_init(struct pcie_port *pp);
 int dw_pcie_link_up(struct pcie_port *pp);
 void dw_pcie_setup_rc(struct pcie_port *pp);
 int dw_pcie_host_init(struct pcie_port *pp);
+void dw_pcie_link_retrain(struct pcie_port *pp);
 
 #endif /* _PCIE_DESIGNWARE_H */
diff --git a/drivers/pci/host/pcie-snpsdev.c b/drivers/pci/host/pcie-snpsdev.c
new file mode 100644
index 0000000..5721da9
--- /dev/null
+++ b/drivers/pci/host/pcie-snpsdev.c
@@ -0,0 +1,342 @@ 
+/*
+ * PCIe RC driver for Synopsys Designware Core
+ *
+ * Copyright (C) 2015-2016 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Authors: Manjunath Bettegowda <manjumb@synopsys.com>,
+ *	    Jie Deng <jiedeng@synopsys.com>
+ *	    Joao Pinto <jpinto@synopsys.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/types.h>
+
+#include "pcie-designware.h"
+
+#define to_snpsdev_pcie(x)	container_of(x, struct snpsdev_pcie, pp)
+
+struct snpsdev_pcie {
+	void __iomem		*mem_base; /* Memory Base to access Core's [RC]
+					    * Config Space Layout
+					    */
+	struct pcie_port	pp;        /* RC Root Port specific structure -
+					    * DWC_PCIE_RC stuff
+					    */
+};
+
+#define SIZE_1GB 0x40000000
+#define PCI_EQUAL_CONTROL_PHY 0x00000707
+
+/* PCIe Port Logic registers (memory-mapped) */
+#define PLR_OFFSET 0x700
+#define PCIE_PHY_DEBUG_R0 (PLR_OFFSET + 0x28) /* 0x728 */
+#define PCIE_PHY_DEBUG_R1 (PLR_OFFSET + 0x2c) /* 0x72c */
+
+/* PCIE PHY CONTROL REGISTER: Useful for cfg_phy_control GPIO outputs */
+#define PCIE_PHY_CTRL (PLR_OFFSET + 0x114)    /* 0x814 */
+/* PCIE PHY STATUS REGISTER: Useful for phy_cfg_status GPIO inputs */
+#define PCIE_PHY_STAT (PLR_OFFSET + 0x110)    /* 0x810 */
+
+static void snpsdev_pcie_fixup_bridge(struct pci_dev *dev)
+{
+	u32 slot_cap;
+
+	u16 caps_reg = pcie_caps_reg(dev) | PCI_EXP_FLAGS_SLOT;
+
+	pcie_capability_write_word(dev, PCI_EXP_FLAGS, caps_reg);
+	dev->pcie_flags_reg = caps_reg;
+
+	pcie_capability_read_dword(dev, PCI_EXP_SLTCAP, &slot_cap);
+
+	slot_cap = slot_cap & (~PCI_EXP_SLTCAP_SPLV);
+	slot_cap = slot_cap | (0x30 << 7);
+
+	pcie_capability_write_dword(dev, PCI_EXP_SLTCAP, slot_cap);
+
+	if (pcibios_enable_device(dev, ~0) < 0)
+		pr_err("PCI: synopsys device enable failed\n");
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, snpsdev_pcie_fixup_bridge);
+
+static void snpsdev_pcie_fixup_res(struct pci_dev *dev)
+{
+	struct resource *res;
+	resource_size_t size;
+	int bar;
+
+	for (bar = 0; bar < 6; bar++) {
+		res = dev->resource + bar;
+		size = resource_size(res);
+
+		if (size == SIZE_1GB) {
+			res->start = 0;
+			res->end   = 0;
+			res->flags = 0;
+		}
+	}
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, snpsdev_pcie_fixup_res);
+
+/* This handler was created for future work */
+static irqreturn_t snpsdev_pcie_irq_handler(int irq, void *arg)
+{
+	return IRQ_NONE;
+}
+
+static irqreturn_t snpsdev_pcie_msi_irq_handler(int irq, void *arg)
+{
+	struct pcie_port *pp = arg;
+
+	dw_handle_msi_irq(pp);
+
+	return IRQ_HANDLED;
+}
+
+static void snpsdev_pcie_init_phy(struct pcie_port *pp)
+{
+	/* write Lane 0 Equalization Control fields register */
+	writel(PCI_EQUAL_CONTROL_PHY, pp->dbi_base + 0x154);
+}
+
+static int snpsdev_pcie_deassert_core_reset(struct pcie_port *pp)
+{
+	return 0;
+}
+
+/*
+ * snpsdev_pcie_host_init()
+ * Platform specific host/RC initialization
+ *	a. Assert the core reset
+ *	b. Assert and deassert phy reset and initialize the phy
+ *	c. De-Assert the core reset
+ *	d. Initializet the Root Port (BARs/Memory Or IO/ Interrupt/ Commnad Reg)
+ *	e. Initiate Link startup procedure
+ *
+ */
+static void snpsdev_pcie_host_init(struct pcie_port *pp)
+{
+	int count = 0;
+
+	/* Initialize Phy (Reset/poweron/control-inputs ) */
+	snpsdev_pcie_init_phy(pp);
+
+	/* de-assert core reset */
+	snpsdev_pcie_deassert_core_reset(pp);
+
+	/* We expect the PCIE Link to be up by this time */
+	dw_pcie_setup_rc(pp);
+
+	/* Start LTSSM here */
+	dw_pcie_link_retrain(pp);
+
+	/* Check for Link up indication */
+	while (!dw_pcie_link_up(pp)) {
+		usleep_range(1000, 1100);
+		count++;
+		if (count == 20) {
+			dev_err(pp->dev, "phy link never came up\n");
+			dev_dbg(pp->dev,
+				"PL_DEBUG0: 0x%08x, DEBUG_R1: 0x%08x\n",
+				readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
+				readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
+			break;
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_PCI_MSI))
+		dw_pcie_msi_init(pp);
+}
+/**
+ *
+ * Let all outof band signalling be handled by cfg_phy_control[31:0]
+ * which is selected through optional config attribute PHY_CONTROL_REG
+ *
+ * Monitor cxpl_debug_info as required to take necessary action
+ * This is available in the register PCIE_PHY_DEBUG_R0 & PCIE_PHY_DEBUG_R1
+ *
+ */
+static int snpsdev_pcie_link_up(struct pcie_port *pp)
+{
+	u32 status;
+
+	/* Bit number 36: reports LTSSM PHY Link UP; Available in bit 3 of
+	 * PCIE_PHY_DEBUG_R1
+	 */
+	status = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1) & (0x1 << 4);
+	if (status != 0)
+		return 1;
+
+	/* TODO:Now Link is in L0;Initiate GEN2/GEN3 migration if RC Supports*/
+	return 0;
+}
+
+
+/**
+ * This is RC operation structure
+ * snpsdev_pcie_link_up: the function which initiates the phy link up procedure
+ * snpsdev_pcie_host_init: the function whihc does the host/RC Root port
+ * initialization.
+ */
+static struct pcie_host_ops snpsdev_pcie_host_ops = {
+	.link_up = snpsdev_pcie_link_up,
+	.host_init = snpsdev_pcie_host_init,
+};
+
+/**
+ * snpsdev_add_pcie_port
+ * This function
+ * a. installs the interrupt handler
+ * b. registers host operations int he pcie_port structure
+ */
+static int snpsdev_add_pcie_port(struct pcie_port *pp,
+				 struct platform_device *pdev)
+{
+	int ret;
+
+	pp->irq = platform_get_irq(pdev, 1);
+
+	if (pp->irq < 0) {
+		if (pp->irq != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "cannot get irq\n");
+		return pp->irq;
+	}
+
+	ret = devm_request_irq(&pdev->dev, pp->irq, snpsdev_pcie_irq_handler,
+				IRQF_SHARED, "snpsdev-pcie", pp);
+
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request irq\n");
+		return ret;
+	}
+
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		pp->msi_irq = platform_get_irq(pdev, 0);
+
+		if (pp->msi_irq < 0) {
+			if (pp->msi_irq != -EPROBE_DEFER)
+				dev_err(&pdev->dev, "cannot get msi irq\n");
+			return pp->msi_irq;
+		}
+
+		ret = devm_request_irq(&pdev->dev, pp->msi_irq,
+					snpsdev_pcie_msi_irq_handler,
+					IRQF_SHARED, "snpsdev-pcie-msi", pp);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to request msi irq\n");
+			return ret;
+		}
+	}
+
+	pp->root_bus_nr = -1;
+	pp->ops = &snpsdev_pcie_host_ops;
+
+	/* Below function:
+	 * Checks for range property from DT
+	 * Gets the IO and MEMORY and CONFIG-Space ranges from DT
+	 * Does IOREMAPS on the physical addresses
+	 * Gets the num-lanes from DT
+	 * Gets MSI capability from DT
+	 * Calls the platform specific host initialization
+	 * Program the correct class, BAR0, Link width, in Config space
+	 * Then it calls pci common init routine
+	 * Then it calls function to assign "unassigned resources"
+	 */
+	ret = dw_pcie_host_init(pp);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to initialize host\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * snpsdev_pcie_rc_probe()
+ * This function gets called as part of pcie registration. if the id matches
+ * the platform driver framework will call this function.
+ *
+ * @pdev: Pointer to the platform_device structure
+ *
+ * Returns zero on success; Negative errorno on failure
+ */
+static int __init snpsdev_pcie_rc_probe(struct platform_device *pdev)
+{
+	struct snpsdev_pcie *snpsdev_pcie;
+	struct pcie_port *pp;
+	struct resource *dwc_pcie_rc_res;  /* Resource from DT */
+	int ret;
+
+	snpsdev_pcie = devm_kzalloc(&pdev->dev, sizeof(*snpsdev_pcie),
+					GFP_KERNEL);
+	if (!snpsdev_pcie)
+		return -ENOMEM;
+
+	pp = &snpsdev_pcie->pp;
+	pp->dev = &pdev->dev;
+
+	dwc_pcie_rc_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	if (!dwc_pcie_rc_res)
+		return -ENODEV;
+
+	snpsdev_pcie->mem_base = devm_ioremap_resource(&pdev->dev,
+							dwc_pcie_rc_res);
+	if (IS_ERR(snpsdev_pcie->mem_base)) {
+		ret = PTR_ERR(snpsdev_pcie->mem_base);
+		return ret;
+	}
+	pp->dbi_base = snpsdev_pcie->mem_base;
+
+	ret = snpsdev_add_pcie_port(pp, pdev);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, snpsdev_pcie);
+
+	return 0;
+}
+
+static int __exit snpsdev_pcie_rc_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id snpsdev_pcie_rc_of_match[] = {
+	{ .compatible = "snps,pcie-snpsdev", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, snpsdev_pcie_rc_of_match);
+
+static struct platform_driver snpsdev_pcie_rc_driver = {
+	.remove		= __exit_p(snpsdev_pcie_rc_remove),
+	.driver = {
+		.name	= "pcie-snpsdev",
+		.owner	= THIS_MODULE,
+		.of_match_table = snpsdev_pcie_rc_of_match,
+	},
+};
+
+static int __init snpsdev_pcie_init(void)
+{
+	return platform_driver_probe(&snpsdev_pcie_rc_driver,
+					snpsdev_pcie_rc_probe);
+}
+subsys_initcall(snpsdev_pcie_init);
+
+MODULE_AUTHOR("Manjunath Bettegowda <manjumb@synopsys.com>");
+MODULE_DESCRIPTION("Platform Driver for Synopsys Device");
+MODULE_LICENSE("GPL v2");