[PATCH 3/5] PCI: st: Provide support for the sti PCIe controller
Gabriel FERNANDEZ
gabriel.fernandez at st.com
Wed Dec 17 02:34:44 PST 2014
sti pcie is built around a Synopsis Designware PCIe IP.
Signed-off-by: Fabrice Gasnier <fabrice.gasnier at st.com>
Signed-off-by: Gabriel Fernandez <gabriel.fernandez at linaro.org>
---
drivers/pci/host/Kconfig | 5 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pci-st.c | 713 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 719 insertions(+)
create mode 100644 drivers/pci/host/pci-st.c
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index c4b6568..999d2b9 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -102,4 +102,9 @@ config PCI_LAYERSCAPE
help
Say Y here if you want PCIe controller support on Layerscape SoCs.
+config PCI_ST
+ bool "ST STiH41x PCIe controller"
+ depends on ARCH_STI
+ select PCIE_DW
+
endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 44c2699..ca14829 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone-dw.o pci-keystone.o
obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
obj-$(CONFIG_PCI_XGENE) += pci-xgene.o
obj-$(CONFIG_PCI_LAYERSCAPE) += pci-layerscape.o
+obj-$(CONFIG_PCI_ST) += pci-st.o
diff --git a/drivers/pci/host/pci-st.c b/drivers/pci/host/pci-st.c
new file mode 100644
index 0000000..bd3d32d
--- /dev/null
+++ b/drivers/pci/host/pci-st.c
@@ -0,0 +1,713 @@
+/*
+ * Copyright (C) 2014 STMicroelectronics
+ *
+ * STMicroelectronics PCI express Driver for sti SoCs.
+ * ST PCIe IPs are built around a Synopsys IP Core.
+ *
+ * Author: Fabrice Gasnier <fabrice.gasnier at st.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/module.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <linux/delay.h>
+#include <linux/reset.h>
+#include <linux/phy/phy.h>
+
+#include "pcie-designware.h"
+
+#define TRANSLATION_CONTROL 0x900
+/* Controls if area is inclusive or exclusive */
+#define RC_PASS_ADDR_RANGE BIT(1)
+
+/* Base of area reserved for config accesses. Fixed size of 64K. */
+#define CFG_BASE_ADDRESS 0x92c
+#define CFG_REGION_SIZE 65536
+
+/* First 4K of config space has this BDF (bus,device,function) */
+#define FUNC0_BDF_NUM 0x930
+
+/* Mem regions */
+#define IN0_MEM_ADDR_START 0x964
+#define IN0_MEM_ADDR_LIMIT 0x968
+#define IN1_MEM_ADDR_START 0x974
+#define IN1_MEM_ADDR_LIMIT 0x978
+
+/* This actually contains the LTSSM state machine state */
+#define PORT_LOGIC_DEBUG_REG_0 0x728
+
+/* LTSSM state machine values */
+#define DEBUG_REG_0_LTSSM_MASK 0x1f
+#define S_DETECT_QUIET 0x00
+#define S_DETECT_ACT 0x01
+#define S_POLL_ACTIVE 0x02
+#define S_POLL_COMPLIANCE 0x03
+#define S_POLL_CONFIG 0x04
+#define S_PRE_DETECT_QUIET 0x05
+#define S_DETECT_WAIT 0x06
+#define S_CFG_LINKWD_START 0x07
+#define S_CFG_LINKWD_ACEPT 0x08
+#define S_CFG_LANENUM_WAIT 0x09
+#define S_CFG_LANENUM_ACEPT 0x0A
+#define S_CFG_COMPLETE 0x0B
+#define S_CFG_IDLE 0x0C
+#define S_RCVRY_LOCK 0x0D
+#define S_RCVRY_SPEED 0x0E
+#define S_RCVRY_RCVRCFG 0x0F
+#define S_RCVRY_IDLE 0x10
+#define S_L0 0x11
+#define S_L0S 0x12
+#define S_L123_SEND_EIDLE 0x13
+#define S_L1_IDLE 0x14
+#define S_L2_IDLE 0x15
+#define S_L2_WAKE 0x16
+#define S_DISABLED_ENTRY 0x17
+#define S_DISABLED_IDLE 0x18
+#define S_DISABLED 0x19
+#define S_LPBK_ENTRY 0x1A
+#define S_LPBK_ACTIVE 0x1B
+#define S_LPBK_EXIT 0x1C
+#define S_LPBK_EXIT_TIMEOUT 0x1D
+#define S_HOT_RESET_ENTRY 0x1E
+#define S_HOT_RESET 0x1F
+
+/* syscfg bits */
+#define PCIE_SYS_INT BIT(5)
+#define PCIE_APP_REQ_RETRY_EN BIT(3)
+#define PCIE_APP_LTSSM_ENABLE BIT(2)
+#define PCIE_APP_INIT_RST BIT(1)
+#define PCIE_DEVICE_TYPE BIT(0)
+#define PCIE_DEFAULT_VAL PCIE_DEVICE_TYPE
+
+/* Time to wait between testing the link in msecs (hardware poll interval) */
+#define LINK_LOOP_DELAY_MS 1
+/* Total amount of time to wait for the link to come up in msecs */
+#define LINK_WAIT_MS 120
+#define LINK_LOOP_COUNT (LINK_WAIT_MS / LINK_LOOP_DELAY_MS)
+
+/* st,syscfg offsets */
+#define SYSCFG0_REG 1
+#define SYSCFG1_REG 2
+
+#define to_st_pcie(x) container_of(x, struct st_pcie, pp)
+
+/**
+ * struct st_pcie_ops - SOC dependent data
+ * @init: reference to controller power & reset init routine
+ * @enable_ltssm: reference to controller link enable routine
+ * @disable_ltssm: reference to controller link disable routine
+ * @phy_auto: flag when phy automatically configured
+ */
+struct st_pcie_ops {
+ int (*init)(struct pcie_port *pp);
+ int (*enable_ltssm)(struct pcie_port *pp);
+ int (*disable_ltssm)(struct pcie_port *pp);
+ bool phy_auto;
+};
+
+/**
+ * struct st_pcie - private data of the controller
+ * @pp: designware pcie port
+ * @syscfg0: PCIe configuration 0 register, regmap offset
+ * @syscfg1: PCIe configuration 1 register, regmap offset
+ * @phy: associated pcie phy
+ * @config_area: PCIe configuration space
+ * @lmi: memory made available to the controller
+ * @data: SOC dependent data
+ * @regmap: Syscfg registers bank in which PCIe port is configured
+ * @pwr: power control
+ * @rst: reset control
+ * @reset_gpio: optional reset gpio
+ * @config_window_start: start address of 64K config space area
+ */
+struct st_pcie {
+ struct pcie_port pp;
+ int syscfg0;
+ int syscfg1;
+ struct phy *phy;
+ void __iomem *config_area;
+ struct resource *lmi;
+ const struct st_pcie_ops *data;
+ struct regmap *regmap;
+ struct reset_control *pwr;
+ struct reset_control *rst;
+ int reset_gpio;
+ phys_addr_t config_window_start;
+};
+
+/*
+ * Function to test if the link is in an operational state or not. We must
+ * ensure the link is operational before we try to do a configuration access.
+ */
+static int st_pcie_link_up(struct pcie_port *pp)
+{
+ u32 status;
+ int link_up;
+ int count = 0;
+
+ /*
+ * We have to be careful here. This is used in config read/write,
+ * The higher levels switch off interrupts, so you cannot use
+ * jiffies to do a timeout, or reschedule
+ */
+ do {
+ /*
+ * What about L2? I think software intervention is
+ * required to get it out of L2, so in effect the link
+ * is down. Requires more work when/if we implement power
+ * management
+ */
+ status = readl_relaxed(pp->dbi_base + PORT_LOGIC_DEBUG_REG_0);
+ status &= DEBUG_REG_0_LTSSM_MASK;
+
+ link_up = (status == S_L0) || (status == S_L0S) ||
+ (status == S_L1_IDLE);
+
+ /*
+ * It can take some considerable time for the link to actually
+ * come up, caused by the PLLs. Experiments indicate it takes
+ * about 8ms to actually bring the link up, but this can vary
+ * considerably according to the specification. This code should
+ * allow sufficient time
+ */
+ if (!link_up)
+ mdelay(LINK_LOOP_DELAY_MS);
+
+ } while (!link_up && ++count < LINK_LOOP_COUNT);
+
+ return link_up;
+}
+
+/*
+ * On ARM platforms, we actually get a bus error returned when the PCIe IP
+ * returns a UR or CRS instead of an OK.
+ */
+static int st_pcie_abort_handler(unsigned long addr, unsigned int fsr,
+ struct pt_regs *regs)
+{
+ return 0;
+}
+
+/*
+ * The PCI express core IP expects the following arrangement on it's address
+ * bus (slv_haddr) when driving config cycles.
+ * bus_number [31:24]
+ * dev_number [23:19]
+ * func_number [18:16]
+ * unused [15:12]
+ * ext_reg_number [11:8]
+ * reg_number [7:2]
+ *
+ * Bits [15:12] are unused.
+ *
+ * In the glue logic there is a 64K region of address space that can be
+ * written/read to generate config cycles. The base address of this is
+ * controlled by CFG_BASE_ADDRESS. There are 8 16 bit registers called
+ * FUNC0_BDF_NUM to FUNC8_BDF_NUM. These split the bottom half of the 64K
+ * window into 8 regions at 4K boundaries. These control the bus,device and
+ * function number you are trying to talk to.
+ *
+ * The decision on whether to generate a type 0 or type 1 access is controlled
+ * by bits 15:12 of the address you write to. If they are zero, then a type 0
+ * is generated, if anything else it will be a type 1. Thus the bottom 4K
+ * region controlled by FUNC0_BDF_NUM can only generate type 0, all the others
+ * can only generate type 1.
+ *
+ * We only use FUNC0_BDF_NUM and FUNC1_BDF_NUM. Which one you use is selected
+ * by bit 12 of the address you write to. The selected register is then used
+ * for the top 16 bits of the slv_haddr to form the bus/dev/func, bit 15:12 are
+ * wired to zero, and bits 11:2 form the address of the register you want to
+ * read in config space.
+ *
+ * We always write FUNC0_BDF_NUM as a 32 bit write. So if we want type 1
+ * accesses we have to shift by 16 so in effect we are writing to FUNC1_BDF_NUM
+ */
+static inline u32 bdf_num(int bus, int devfn, int is_root_bus)
+{
+ return ((bus << 8) | devfn) << (is_root_bus ? 0 : 16);
+}
+
+static inline unsigned config_addr(int where, int is_root_bus)
+{
+ return (where & ~3) | (!is_root_bus << 12);
+}
+
+static int st_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+ unsigned int devfn, int where, int size,
+ u32 *val)
+{
+ u32 data;
+ u32 bdf;
+ struct st_pcie *pcie = to_st_pcie(pp);
+ int is_root_bus = pci_is_root_bus(bus);
+ int retry_count = 0;
+ int ret;
+ void __iomem *addr;
+
+ /*
+ * Prerequisite
+ * PCI express devices will respond to all config type 0 cycles, since
+ * they are point to point links. Thus to avoid probing for multiple
+ * devices on the root, dw-pcie already check for us if it is on the
+ * root bus / other slots. Also, dw-pcie checks for the link being up
+ * as we will hang if we issue a config request and the link is down.
+ * A switch will reject requests for slots it knows do not exist.
+ */
+ bdf = bdf_num(bus->number, devfn, is_root_bus);
+ addr = pcie->config_area + config_addr(where,
+ bus->parent->number == pp->root_bus_nr);
+retry:
+ /* Set the config packet devfn */
+ writel_relaxed(bdf, pp->dbi_base + FUNC0_BDF_NUM);
+ readl_relaxed(pp->dbi_base + FUNC0_BDF_NUM);
+
+ ret = dw_pcie_cfg_read(addr, where, size, &data);
+
+ /*
+ * This is intended to help with when we are probing the bus. The
+ * problem is that the wrapper logic doesn't have any way to
+ * interrogate if the configuration request failed or not.
+ * On the ARM we actually get a real bus error.
+ *
+ * Unfortunately this means it is impossible to tell the difference
+ * between when a device doesn't exist (the switch will return a UR
+ * completion) or the device does exist but isn't yet ready to accept
+ * configuration requests (the device will return a CRS completion)
+ *
+ * The result of this is that we will miss devices when probing.
+ *
+ * So if we are trying to read the dev/vendor id on devfn 0 and we
+ * appear to get zero back, then we retry the request. We know that
+ * zero can never be a valid device/vendor id. The specification says
+ * we must retry for up to a second before we decide the device is
+ * dead. If we are still dead then we assume there is nothing there and
+ * return ~0
+ *
+ * The downside of this is that we incur a delay of 1s for every pci
+ * express link that doesn't have a device connected.
+ */
+ if (((where & ~3) == 0) && devfn == 0 && (data == 0 || data == ~0)) {
+ if (retry_count++ < 1000) {
+ mdelay(1);
+ goto retry;
+ } else {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ }
+
+ *val = data;
+ return ret;
+}
+
+static int st_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
+ unsigned int devfn, int where, int size,
+ u32 val)
+{
+ u32 bdf;
+ struct st_pcie *pcie = to_st_pcie(pp);
+ int is_root_bus = pci_is_root_bus(bus);
+ void __iomem *addr;
+
+ bdf = bdf_num(bus->number, devfn, is_root_bus);
+ addr = pcie->config_area + config_addr(where,
+ bus->parent->number == pp->root_bus_nr);
+
+ /* Set the config packet devfn */
+ writel_relaxed(bdf, pp->dbi_base + FUNC0_BDF_NUM);
+ readl_relaxed(pp->dbi_base + FUNC0_BDF_NUM);
+
+ return dw_pcie_cfg_write(addr, where, size, val);
+}
+
+static void st_pcie_board_reset(struct pcie_port *pp)
+{
+ struct st_pcie *pcie = to_st_pcie(pp);
+
+ if (!gpio_is_valid(pcie->reset_gpio))
+ return;
+
+ if (gpio_direction_output(pcie->reset_gpio, 0)) {
+ dev_err(pp->dev, "Cannot set PERST# (gpio %u) to output\n",
+ pcie->reset_gpio);
+ return;
+ }
+
+ /* From PCIe spec */
+ usleep_range(1000, 2000);
+ gpio_direction_output(pcie->reset_gpio, 1);
+
+ /*
+ * PCIe specification states that you should not issue any config
+ * requests until 100ms after asserting reset, so we enforce that here
+ */
+ usleep_range(100000, 150000);
+}
+
+static void st_pcie_hw_setup(struct pcie_port *pp)
+{
+ struct st_pcie *pcie = to_st_pcie(pp);
+
+ dw_pcie_setup_rc(pp);
+
+ /* Set up the config window to the top of the PCI address space */
+ writel_relaxed(pcie->config_window_start,
+ pp->dbi_base + CFG_BASE_ADDRESS);
+
+ /*
+ * Open up memory to the PCI controller. We could do slightly
+ * better than this and exclude the kernel text segment and bss etc.
+ * They are base/limit registers so can be of arbitrary alignment
+ * presumably
+ */
+ writel_relaxed(pcie->lmi->start, pp->dbi_base + IN0_MEM_ADDR_START);
+ writel_relaxed(pcie->lmi->end, pp->dbi_base + IN0_MEM_ADDR_LIMIT);
+
+ /* Disable the 2nd region */
+ writel_relaxed(~0, pp->dbi_base + IN1_MEM_ADDR_START);
+ writel_relaxed(0, pp->dbi_base + IN1_MEM_ADDR_LIMIT);
+
+ writel_relaxed(RC_PASS_ADDR_RANGE, pp->dbi_base + TRANSLATION_CONTROL);
+
+ /* Now assert the board level reset to the other PCIe device */
+ st_pcie_board_reset(pp);
+}
+
+static irqreturn_t st_pcie_msi_irq_handler(int irq, void *arg)
+{
+ struct pcie_port *pp = arg;
+
+ return dw_handle_msi_irq(pp);
+}
+
+static void st_msi_init_one(struct pcie_port *pp)
+{
+ struct st_pcie *pcie = to_st_pcie(pp);
+
+ /*
+ * Set the magic address the hardware responds to. This has to be in
+ * the range the PCI controller can write to.
+ */
+ dw_pcie_msi_init(pp);
+
+ if ((virt_to_phys((void *)pp->msi_data) < pcie->lmi->start) ||
+ (virt_to_phys((void *)pp->msi_data) > pcie->lmi->end))
+ dev_err(pp->dev, "MSI addr miss-configured\n");
+}
+
+static void st_pcie_host_init(struct pcie_port *pp)
+{
+ struct st_pcie *pcie = to_st_pcie(pp);
+ int err;
+
+ /*
+ * We have to initialise the PCIe cell on some hardware before we can
+ * talk to the phy
+ */
+ err = pcie->data->init(pp);
+ if (err)
+ return;
+
+ err = pcie->data->disable_ltssm(pp);
+ if (err) {
+ dev_err(pp->dev, "disable ltssm failed, %d\n", err);
+ return;
+ }
+
+ if (!pcie->data->phy_auto) {
+ /* Now init the associated miphy */
+ err = phy_init(pcie->phy);
+ if (err < 0) {
+ dev_err(pp->dev, "Cannot init PHY: %d\n", err);
+ return;
+ }
+ }
+
+ /* Now do all the register poking */
+ st_pcie_hw_setup(pp);
+
+ /* Re-enable the link */
+ err = pcie->data->enable_ltssm(pp);
+ if (err)
+ dev_err(pp->dev, "enable ltssm failed, %d\n", err);
+
+ if (IS_ENABLED(CONFIG_PCI_MSI))
+ st_msi_init_one(pp);
+}
+
+static struct pcie_host_ops st_pcie_host_ops = {
+ .rd_other_conf = st_pcie_rd_other_conf,
+ .wr_other_conf = st_pcie_wr_other_conf,
+ .link_up = st_pcie_link_up,
+ .host_init = st_pcie_host_init,
+};
+
+static int st_pcie_init(struct pcie_port *pp)
+{
+ struct st_pcie *pcie = to_st_pcie(pp);
+ int ret;
+
+ ret = reset_control_deassert(pcie->pwr);
+ if (ret) {
+ dev_err(pp->dev, "unable to bring out of powerdown\n");
+ return ret;
+ }
+
+ ret = reset_control_deassert(pcie->rst);
+ if (ret) {
+ dev_err(pp->dev, "unable to bring out of softreset\n");
+ return ret;
+ }
+
+ /* Set device type : Root Complex */
+ ret = regmap_write(pcie->regmap, pcie->syscfg0, PCIE_DEVICE_TYPE);
+ if (ret < 0) {
+ dev_err(pp->dev, "unable to set device type\n");
+ return ret;
+ }
+
+ usleep_range(1000, 2000);
+ return ret;
+}
+
+/* STiH407 */
+static int stih407_pcie_enable_ltssm(struct pcie_port *pp)
+{
+ struct st_pcie *pcie = to_st_pcie(pp);
+
+ if (!pcie->syscfg1)
+ return -EINVAL;
+
+ return regmap_update_bits(pcie->regmap, pcie->syscfg1,
+ PCIE_APP_LTSSM_ENABLE, PCIE_APP_LTSSM_ENABLE);
+}
+
+static int stih407_pcie_disable_ltssm(struct pcie_port *pp)
+{
+ struct st_pcie *pcie = to_st_pcie(pp);
+
+ if (!pcie->syscfg1)
+ return -EINVAL;
+
+ return regmap_update_bits(pcie->regmap, pcie->syscfg1,
+ PCIE_APP_LTSSM_ENABLE, 0);
+}
+
+static struct st_pcie_ops stih407_pcie_ops = {
+ .init = st_pcie_init,
+ .enable_ltssm = stih407_pcie_enable_ltssm,
+ .disable_ltssm = stih407_pcie_disable_ltssm,
+};
+
+static const struct of_device_id st_pcie_of_match[] = {
+ { .compatible = "st,stih407-pcie", .data = (void *)&stih407_pcie_ops},
+ { },
+};
+
+#ifdef CONFIG_PM
+static int st_pcie_suspend(struct device *pcie_dev)
+{
+ struct st_pcie *pcie = dev_get_drvdata(pcie_dev);
+
+ /* To guarantee a real phy initialization on resume */
+ if (!pcie->data->phy_auto)
+ phy_exit(pcie->phy);
+
+ return 0;
+}
+
+static int st_pcie_resume(struct device *pcie_dev)
+{
+ struct st_pcie *pcie = dev_get_drvdata(pcie_dev);
+
+ st_pcie_host_init(&pcie->pp);
+
+ return 0;
+}
+#endif
+
+const struct dev_pm_ops st_pcie_pm_ops = {
+ .suspend_noirq = st_pcie_suspend,
+ .resume_noirq = st_pcie_resume,
+};
+
+static int __init st_pcie_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct st_pcie *pcie;
+ struct device_node *np = pdev->dev.of_node;
+ struct pcie_port *pp;
+ int ret;
+
+ pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
+ if (!pcie)
+ return -ENOMEM;
+
+ memset(pcie, 0, sizeof(*pcie));
+
+ pp = &pcie->pp;
+ pp->dev = &pdev->dev;
+
+ /* mem regions */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+ pp->dbi_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pp->dbi_base))
+ return PTR_ERR(pp->dbi_base);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "config");
+ if (!res)
+ return -ENXIO;
+
+ /* Check that this has sensible values */
+ if ((resource_size(res) != CFG_REGION_SIZE) ||
+ (res->start & (CFG_REGION_SIZE - 1))) {
+ dev_err(&pdev->dev, "Invalid config space properties\n");
+ return -EINVAL;
+ }
+ pcie->config_window_start = res->start;
+
+ pcie->config_area = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pcie->config_area))
+ return PTR_ERR(pcie->config_area);
+
+ pcie->lmi = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "mem-window");
+ if (!pcie->lmi)
+ return -ENXIO;
+
+ /* regmap registers for PCIe IP configuration */
+ pcie->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+ if (IS_ERR(pcie->regmap)) {
+ dev_err(&pdev->dev, "No syscfg phandle specified\n");
+ return PTR_ERR(pcie->regmap);
+ }
+
+ ret = of_property_read_u32_index(np, "st,syscfg", SYSCFG0_REG,
+ &pcie->syscfg0);
+ if (ret) {
+ dev_err(&pdev->dev, "can't get syscfg0 offset (%d)\n", ret);
+ return ret;
+ }
+
+ ret = of_property_read_u32_index(np, "st,syscfg", SYSCFG1_REG,
+ &pcie->syscfg1);
+ if (ret) {
+ dev_err(&pdev->dev, "can't get syscfg1 offset (%d)\n", ret);
+ return ret;
+ }
+
+ /* retrieve data opts from compatible */
+ pcie->data = of_match_node(st_pcie_of_match, np)->data;
+ if (!pcie->data) {
+ dev_err(&pdev->dev, "compatible data not provided\n");
+ return -EINVAL;
+ }
+
+ /* powerdown / resets */
+ pcie->pwr = devm_reset_control_get(&pdev->dev, "powerdown");
+ if (IS_ERR(pcie->pwr)) {
+ dev_err(&pdev->dev, "powerdown reset control not defined\n");
+ return -EINVAL;
+ }
+
+ pcie->rst = devm_reset_control_get(&pdev->dev, "softreset");
+ if (IS_ERR(pcie->rst)) {
+ dev_err(&pdev->dev, "Soft reset control not defined\n");
+ return -EINVAL;
+ }
+
+ /* phy */
+ if (!pcie->data->phy_auto) {
+ pcie->phy = devm_phy_get(&pdev->dev, "pcie_phy");
+ if (IS_ERR(pcie->phy)) {
+ dev_err(&pdev->dev, "no PHY configured\n");
+ return PTR_ERR(pcie->phy);
+ }
+ }
+
+ /* Claim the GPIO for PRST# if available */
+ pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+ if (!gpio_is_valid(pcie->reset_gpio))
+ dev_dbg(&pdev->dev, "No reset-gpio configured\n");
+ else {
+ ret = devm_gpio_request(&pdev->dev,
+ pcie->reset_gpio,
+ "PCIe reset");
+ if (ret) {
+ dev_err(&pdev->dev, "Cannot request reset-gpio %d\n",
+ pcie->reset_gpio);
+ return ret;
+ }
+ }
+
+ if (IS_ENABLED(CONFIG_PCI_MSI)) {
+ pp->msi_irq = platform_get_irq_byname(pdev, "msi");
+ if (pp->msi_irq <= 0) {
+ dev_err(&pdev->dev, "failed to get MSI irq\n");
+ return -ENODEV;
+ }
+
+ ret = devm_request_irq(&pdev->dev, pp->msi_irq,
+ st_pcie_msi_irq_handler,
+ IRQF_SHARED, "st-pcie-msi", pp);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request MSI irq\n");
+ return -ENODEV;
+ }
+ }
+
+ if (IS_ENABLED(CONFIG_ARM)) {
+ /*
+ * We have to hook the abort handler so that we can intercept
+ * bus errors when doing config read/write that return UR,
+ * which is flagged up as a bus error
+ */
+ hook_fault_code(16+6, st_pcie_abort_handler, SIGBUS, 0,
+ "imprecise external abort");
+ }
+
+ pp->root_bus_nr = -1;
+ pp->ops = &st_pcie_host_ops;
+
+ ret = dw_pcie_host_init(pp);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to initialize host\n");
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, pcie);
+
+ dev_info(&pdev->dev, "Initialized\n");
+ return 0;
+}
+
+MODULE_DEVICE_TABLE(of, st_pcie_of_match);
+
+static struct platform_driver st_pcie_driver = {
+ .driver = {
+ .name = "st-pcie",
+ .of_match_table = st_pcie_of_match,
+ .pm = &st_pcie_pm_ops,
+ },
+};
+
+/* ST PCIe driver does not allow module unload */
+static int __init pcie_init(void)
+{
+ return platform_driver_probe(&st_pcie_driver, st_pcie_probe);
+}
+device_initcall(pcie_init);
+
+MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier at st.com>");
+MODULE_DESCRIPTION("PCI express Driver for ST SoCs");
+MODULE_LICENSE("GPLv2");
--
1.9.1
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