[PATCH 3/5] PCI: st: Provide support for the sti PCIe controller
Gabriel Fernandez
gabriel.fernandez at linaro.org
Mon Jan 19 05:06:28 PST 2015
Hi Jingoo,
Thanks for reviewing
On 18 December 2014 at 07:03, Jingoo Han <jg1.han at samsung.com> wrote:
> On Wednesday, December 17, 2014 7:35 PM, Gabriel FERNANDEZ wrote:
>>
>> 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>
>
> Please, re-order these headers alphabetically.
> It enhances the readability.
>
sure
>> +
>> +#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;
>
> Please return PTR_ERR(pcie->pwr) instead of '-EINVAL'.
>
ok
>> + }
>> +
>> + 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;
>
> Please return PTR_ERR(pcie->pwr) instead of '-EINVAL'.
>
ok
>> + }
>> +
>> + /* 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");
>
> Please add one space between 'GPL' and 'v2'.
>
> s/"GPLv2"/"GPL v2"
>
> According to the license_is_gpl_compatible(), the MODULE_LICENSE() string
> for GPL v2 is "GPL v2" not "GPLv2".
>
ok
> Best regards,
> Jingoo Han
>
>> --
>> 1.9.1
>
BR
Gabriel
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