--- /dev/null
+/*
+ * PCIe host controller driver for Freescale i.MX6 SoCs
+ *
+ * Copyright (C) 2013 Kosagi
+ * http://www.kosagi.com
+ *
+ * Author: Sean Cross <xobs@kosagi.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/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/resource.h>
+#include <linux/signal.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+
+#include "pcie-designware.h"
+
+#define to_imx6_pcie(x) container_of(x, struct imx6_pcie, pp)
+
+struct imx6_pcie {
+ int reset_gpio;
+ struct clk *pcie_bus;
+ struct clk *pcie_phy;
+ struct clk *pcie;
+ struct pcie_port pp;
+ struct regmap *iomuxc_gpr;
+ void __iomem *mem_base;
+};
+
+/* PCIe Root Complex registers (memory-mapped) */
+#define PCIE_RC_LCR 0x7c
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2 0x2
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK 0xf
+
+/* PCIe Port Logic registers (memory-mapped) */
+#define PL_OFFSET 0x700
+#define PCIE_PL_PFLR (PL_OFFSET + 0x08)
+#define PCIE_PL_PFLR_LINK_STATE_MASK (0x3f << 16)
+#define PCIE_PL_PFLR_FORCE_LINK (1 << 15)
+#define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
+#define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
+#define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING (1 << 29)
+#define PCIE_PHY_DEBUG_R1_XMLH_LINK_UP (1 << 4)
+
+#define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
+#define PCIE_PHY_CTRL_DATA_LOC 0
+#define PCIE_PHY_CTRL_CAP_ADR_LOC 16
+#define PCIE_PHY_CTRL_CAP_DAT_LOC 17
+#define PCIE_PHY_CTRL_WR_LOC 18
+#define PCIE_PHY_CTRL_RD_LOC 19
+
+#define PCIE_PHY_STAT (PL_OFFSET + 0x110)
+#define PCIE_PHY_STAT_ACK_LOC 16
+
+#define PCIE_LINK_WIDTH_SPEED_CONTROL 0x80C
+#define PORT_LOGIC_SPEED_CHANGE (0x1 << 17)
+
+/* PHY registers (not memory-mapped) */
+#define PCIE_PHY_RX_ASIC_OUT 0x100D
+
+#define PHY_RX_OVRD_IN_LO 0x1005
+#define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5)
+#define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3)
+
+static int pcie_phy_poll_ack(void __iomem *dbi_base, int exp_val)
+{
+ u32 val;
+ u32 max_iterations = 10;
+ u32 wait_counter = 0;
+
+ do {
+ val = readl(dbi_base + PCIE_PHY_STAT);
+ val = (val >> PCIE_PHY_STAT_ACK_LOC) & 0x1;
+ wait_counter++;
+
+ if (val == exp_val)
+ return 0;
+
+ udelay(1);
+ } while (wait_counter < max_iterations);
+
+ return -ETIMEDOUT;
+}
+
+static int pcie_phy_wait_ack(void __iomem *dbi_base, int addr)
+{
+ u32 val;
+ int ret;
+
+ val = addr << PCIE_PHY_CTRL_DATA_LOC;
+ writel(val, dbi_base + PCIE_PHY_CTRL);
+
+ val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC);
+ writel(val, dbi_base + PCIE_PHY_CTRL);
+
+ ret = pcie_phy_poll_ack(dbi_base, 1);
+ if (ret)
+ return ret;
+
+ val = addr << PCIE_PHY_CTRL_DATA_LOC;
+ writel(val, dbi_base + PCIE_PHY_CTRL);
+
+ ret = pcie_phy_poll_ack(dbi_base, 0);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
+static int pcie_phy_read(void __iomem *dbi_base, int addr , int *data)
+{
+ u32 val, phy_ctl;
+ int ret;
+
+ ret = pcie_phy_wait_ack(dbi_base, addr);
+ if (ret)
+ return ret;
+
+ /* assert Read signal */
+ phy_ctl = 0x1 << PCIE_PHY_CTRL_RD_LOC;
+ writel(phy_ctl, dbi_base + PCIE_PHY_CTRL);
+
+ ret = pcie_phy_poll_ack(dbi_base, 1);
+ if (ret)
+ return ret;
+
+ val = readl(dbi_base + PCIE_PHY_STAT);
+ *data = val & 0xffff;
+
+ /* deassert Read signal */
+ writel(0x00, dbi_base + PCIE_PHY_CTRL);
+
+ ret = pcie_phy_poll_ack(dbi_base, 0);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int pcie_phy_write(void __iomem *dbi_base, int addr, int data)
+{
+ u32 var;
+ int ret;
+
+ /* write addr */
+ /* cap addr */
+ ret = pcie_phy_wait_ack(dbi_base, addr);
+ if (ret)
+ return ret;
+
+ var = data << PCIE_PHY_CTRL_DATA_LOC;
+ writel(var, dbi_base + PCIE_PHY_CTRL);
+
+ /* capture data */
+ var |= (0x1 << PCIE_PHY_CTRL_CAP_DAT_LOC);
+ writel(var, dbi_base + PCIE_PHY_CTRL);
+
+ ret = pcie_phy_poll_ack(dbi_base, 1);
+ if (ret)
+ return ret;
+
+ /* deassert cap data */
+ var = data << PCIE_PHY_CTRL_DATA_LOC;
+ writel(var, dbi_base + PCIE_PHY_CTRL);
+
+ /* wait for ack de-assertion */
+ ret = pcie_phy_poll_ack(dbi_base, 0);
+ if (ret)
+ return ret;
+
+ /* assert wr signal */
+ var = 0x1 << PCIE_PHY_CTRL_WR_LOC;
+ writel(var, dbi_base + PCIE_PHY_CTRL);
+
+ /* wait for ack */
+ ret = pcie_phy_poll_ack(dbi_base, 1);
+ if (ret)
+ return ret;
+
+ /* deassert wr signal */
+ var = data << PCIE_PHY_CTRL_DATA_LOC;
+ writel(var, dbi_base + PCIE_PHY_CTRL);
+
+ /* wait for ack de-assertion */
+ ret = pcie_phy_poll_ack(dbi_base, 0);
+ if (ret)
+ return ret;
+
+ writel(0x0, dbi_base + PCIE_PHY_CTRL);
+
+ return 0;
+}
+
+/* Added for PCI abort handling */
+static int imx6q_pcie_abort_handler(unsigned long addr,
+ unsigned int fsr, struct pt_regs *regs)
+{
+ return 0;
+}
+
+static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
+{
+ struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+ u32 val, gpr1, gpr12;
+
+ /*
+ * If the bootloader already enabled the link we need some special
+ * handling to get the core back into a state where it is safe to
+ * touch it for configuration. As there is no dedicated reset signal
+ * wired up for MX6QDL, we need to manually force LTSSM into "detect"
+ * state before completely disabling LTSSM, which is a prerequisite
+ * for core configuration.
+ *
+ * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a strong
+ * indication that the bootloader activated the link.
+ */
+ regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, &gpr1);
+ regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, &gpr12);
+
+ if ((gpr1 & IMX6Q_GPR1_PCIE_REF_CLK_EN) &&
+ (gpr12 & IMX6Q_GPR12_PCIE_CTL_2)) {
+ val = readl(pp->dbi_base + PCIE_PL_PFLR);
+ val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
+ val |= PCIE_PL_PFLR_FORCE_LINK;
+ writel(val, pp->dbi_base + PCIE_PL_PFLR);
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
+ }
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
+
+ return 0;
+}
+
+static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
+{
+ struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+ int ret;
+
+ ret = clk_prepare_enable(imx6_pcie->pcie_phy);
+ if (ret) {
+ dev_err(pp->dev, "unable to enable pcie_phy clock\n");
+ goto err_pcie_phy;
+ }
+
+ ret = clk_prepare_enable(imx6_pcie->pcie_bus);
+ if (ret) {
+ dev_err(pp->dev, "unable to enable pcie_bus clock\n");
+ goto err_pcie_bus;
+ }
+
+ ret = clk_prepare_enable(imx6_pcie->pcie);
+ if (ret) {
+ dev_err(pp->dev, "unable to enable pcie clock\n");
+ goto err_pcie;
+ }
+
+ /* power up core phy and enable ref clock */
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
+ /*
+ * the async reset input need ref clock to sync internally,
+ * when the ref clock comes after reset, internal synced
+ * reset time is too short, cannot meet the requirement.
+ * add one ~10us delay here.
+ */
+ udelay(10);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
+
+ /* allow the clocks to stabilize */
+ usleep_range(200, 500);
+
+ /* Some boards don't have PCIe reset GPIO. */
+ if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+ gpio_set_value(imx6_pcie->reset_gpio, 0);
+ msleep(100);
+ gpio_set_value(imx6_pcie->reset_gpio, 1);
+ }
+ return 0;
+
+err_pcie:
+ clk_disable_unprepare(imx6_pcie->pcie_bus);
+err_pcie_bus:
+ clk_disable_unprepare(imx6_pcie->pcie_phy);
+err_pcie_phy:
+ return ret;
+
+}
+
+static void imx6_pcie_init_phy(struct pcie_port *pp)
+{
+ struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
+
+ /* configure constant input signal to the pcie ctrl and phy */
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT << 12);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_DEEMPH_GEN1, 0 << 0);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB, 0 << 6);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB, 20 << 12);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_SWING_FULL, 127 << 18);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_SWING_LOW, 127 << 25);
+}
+
+static int imx6_pcie_wait_for_link(struct pcie_port *pp)
+{
+ int count = 200;
+
+ while (!dw_pcie_link_up(pp)) {
+ usleep_range(100, 1000);
+ if (--count)
+ continue;
+
+ dev_err(pp->dev, "phy link never came up\n");
+ dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
+ readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
+ readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static irqreturn_t imx6_pcie_msi_handler(int irq, void *arg)
+{
+ struct pcie_port *pp = arg;
+
+ return dw_handle_msi_irq(pp);
+}
+
+static int imx6_pcie_start_link(struct pcie_port *pp)
+{
+ struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+ uint32_t tmp;
+ int ret, count;
+
+ /*
+ * Force Gen1 operation when starting the link. In case the link is
+ * started in Gen2 mode, there is a possibility the devices on the
+ * bus will not be detected at all. This happens with PCIe switches.
+ */
+ tmp = readl(pp->dbi_base + PCIE_RC_LCR);
+ tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+ tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1;
+ writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+
+ /* Start LTSSM. */
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
+
+ ret = imx6_pcie_wait_for_link(pp);
+ if (ret)
+ return ret;
+
+ /* Allow Gen2 mode after the link is up. */
+ tmp = readl(pp->dbi_base + PCIE_RC_LCR);
+ tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+ tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
+ writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+
+ /*
+ * Start Directed Speed Change so the best possible speed both link
+ * partners support can be negotiated.
+ */
+ tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+ tmp |= PORT_LOGIC_SPEED_CHANGE;
+ writel(tmp, pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+
+ count = 200;
+ while (count--) {
+ tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+ /* Test if the speed change finished. */
+ if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
+ break;
+ usleep_range(100, 1000);
+ }
+
+ /* Make sure link training is finished as well! */
+ if (count)
+ ret = imx6_pcie_wait_for_link(pp);
+ else
+ ret = -EINVAL;
+
+ if (ret) {
+ dev_err(pp->dev, "Failed to bring link up!\n");
+ } else {
+ tmp = readl(pp->dbi_base + 0x80);
+ dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
+ }
+
+ return ret;
+}
+
+static void imx6_pcie_host_init(struct pcie_port *pp)
+{
+ imx6_pcie_assert_core_reset(pp);
+
+ imx6_pcie_init_phy(pp);
+
+ imx6_pcie_deassert_core_reset(pp);
+
+ dw_pcie_setup_rc(pp);
+
+ imx6_pcie_start_link(pp);
+
+ if (IS_ENABLED(CONFIG_PCI_MSI))
+ dw_pcie_msi_init(pp);
+}
+
+static void imx6_pcie_reset_phy(struct pcie_port *pp)
+{
+ uint32_t temp;
+
+ pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
+ temp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+ PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+ pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
+
+ usleep_range(2000, 3000);
+
+ pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
+ temp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+ PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+ pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
+}
+
+static int imx6_pcie_link_up(struct pcie_port *pp)
+{
+ u32 rc, debug_r0, rx_valid;
+ int count = 5;
+
+ /*
+ * Test if the PHY reports that the link is up and also that the LTSSM
+ * training finished. There are three possible states of the link when
+ * this code is called:
+ * 1) The link is DOWN (unlikely)
+ * The link didn't come up yet for some reason. This usually means
+ * we have a real problem somewhere. Reset the PHY and exit. This
+ * state calls for inspection of the DEBUG registers.
+ * 2) The link is UP, but still in LTSSM training
+ * Wait for the training to finish, which should take a very short
+ * time. If the training does not finish, we have a problem and we
+ * need to inspect the DEBUG registers. If the training does finish,
+ * the link is up and operating correctly.
+ * 3) The link is UP and no longer in LTSSM training
+ * The link is up and operating correctly.
+ */
+ while (1) {
+ rc = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1);
+ if (!(rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_UP))
+ break;
+ if (!(rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING))
+ return 1;
+ if (!count--)
+ break;
+ dev_dbg(pp->dev, "Link is up, but still in training\n");
+ /*
+ * Wait a little bit, then re-check if the link finished
+ * the training.
+ */
+ usleep_range(1000, 2000);
+ }
+ /*
+ * From L0, initiate MAC entry to gen2 if EP/RC supports gen2.
+ * Wait 2ms (LTSSM timeout is 24ms, PHY lock is ~5us in gen2).
+ * If (MAC/LTSSM.state == Recovery.RcvrLock)
+ * && (PHY/rx_valid==0) then pulse PHY/rx_reset. Transition
+ * to gen2 is stuck
+ */
+ pcie_phy_read(pp->dbi_base, PCIE_PHY_RX_ASIC_OUT, &rx_valid);
+ debug_r0 = readl(pp->dbi_base + PCIE_PHY_DEBUG_R0);
+
+ if (rx_valid & 0x01)
+ return 0;
+
+ if ((debug_r0 & 0x3f) != 0x0d)
+ return 0;
+
+ dev_err(pp->dev, "transition to gen2 is stuck, reset PHY!\n");
+ dev_dbg(pp->dev, "debug_r0=%08x debug_r1=%08x\n", debug_r0, rc);
+
+ imx6_pcie_reset_phy(pp);
+
+ return 0;
+}
+
+static struct pcie_host_ops imx6_pcie_host_ops = {
+ .link_up = imx6_pcie_link_up,
+ .host_init = imx6_pcie_host_init,
+};
+
+static int __init imx6_add_pcie_port(struct pcie_port *pp,
+ struct platform_device *pdev)
+{
+ int 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,
+ imx6_pcie_msi_handler,
+ IRQF_SHARED, "mx6-pcie-msi", pp);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request MSI irq\n");
+ return -ENODEV;
+ }
+ }
+
+ pp->root_bus_nr = -1;
+ pp->ops = &imx6_pcie_host_ops;
+
+ ret = dw_pcie_host_init(pp);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to initialize host\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int __init imx6_pcie_probe(struct platform_device *pdev)
+{
+ struct imx6_pcie *imx6_pcie;
+ struct pcie_port *pp;
+ struct device_node *np = pdev->dev.of_node;
+ struct resource *dbi_base;
+ int ret;
+
+ imx6_pcie = devm_kzalloc(&pdev->dev, sizeof(*imx6_pcie), GFP_KERNEL);
+ if (!imx6_pcie)
+ return -ENOMEM;
+
+ pp = &imx6_pcie->pp;
+ pp->dev = &pdev->dev;
+
+ /* Added for PCI abort handling */
+ hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0,
+ "imprecise external abort");
+
+ dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pp->dbi_base = devm_ioremap_resource(&pdev->dev, dbi_base);
+ if (IS_ERR(pp->dbi_base))
+ return PTR_ERR(pp->dbi_base);
+
+ /* Fetch GPIOs */
+ imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
+ if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+ ret = devm_gpio_request_one(&pdev->dev, imx6_pcie->reset_gpio,
+ GPIOF_OUT_INIT_LOW, "PCIe reset");
+ if (ret) {
+ dev_err(&pdev->dev, "unable to get reset gpio\n");
+ return ret;
+ }
+ }
+
+ /* Fetch clocks */
+ imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy");
+ if (IS_ERR(imx6_pcie->pcie_phy)) {
+ dev_err(&pdev->dev,
+ "pcie_phy clock source missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie_phy);
+ }
+
+ imx6_pcie->pcie_bus = devm_clk_get(&pdev->dev, "pcie_bus");
+ if (IS_ERR(imx6_pcie->pcie_bus)) {
+ dev_err(&pdev->dev,
+ "pcie_bus clock source missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie_bus);
+ }
+
+ imx6_pcie->pcie = devm_clk_get(&pdev->dev, "pcie");
+ if (IS_ERR(imx6_pcie->pcie)) {
+ dev_err(&pdev->dev,
+ "pcie clock source missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie);
+ }
+
+ /* Grab GPR config register range */
+ imx6_pcie->iomuxc_gpr =
+ syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
+ if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
+ dev_err(&pdev->dev, "unable to find iomuxc registers\n");
+ return PTR_ERR(imx6_pcie->iomuxc_gpr);
+ }
+
+ ret = imx6_add_pcie_port(pp, pdev);
+ if (ret < 0)
+ return ret;
+
+ platform_set_drvdata(pdev, imx6_pcie);
+ return 0;
+}
+
+static void imx6_pcie_shutdown(struct platform_device *pdev)
+{
+ struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
+
+ /* bring down link, so bootloader gets clean state in case of reboot */
+ imx6_pcie_assert_core_reset(&imx6_pcie->pp);
+}
+
+static const struct of_device_id imx6_pcie_of_match[] = {
+ { .compatible = "fsl,imx6q-pcie", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, imx6_pcie_of_match);
+
+static struct platform_driver imx6_pcie_driver = {
+ .driver = {
+ .name = "imx6q-pcie",
+ .of_match_table = imx6_pcie_of_match,
+ },
+ .shutdown = imx6_pcie_shutdown,
+};
+
+/* Freescale PCIe driver does not allow module unload */
+
+static int __init imx6_pcie_init(void)
+{
+ return platform_driver_probe(&imx6_pcie_driver, imx6_pcie_probe);
+}
+module_init(imx6_pcie_init);
+
+MODULE_AUTHOR("Sean Cross <xobs@kosagi.com>");
+MODULE_DESCRIPTION("Freescale i.MX6 PCIe host controller driver");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff