--- /dev/null
- struct dw_pcie *pci = imx6_pcie->pci;
- u32 val, gpr1, gpr12;
-
+/*
+ * 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/of_device.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) dev_get_drvdata((x)->dev)
+
+enum imx6_pcie_variants {
+ IMX6Q,
+ IMX6SX,
+ IMX6QP,
+};
+
+struct imx6_pcie {
+ struct dw_pcie *pci;
+ int reset_gpio;
+ bool gpio_active_high;
+ struct clk *pcie_bus;
+ struct clk *pcie_phy;
+ struct clk *pcie_inbound_axi;
+ struct clk *pcie;
+ struct regmap *iomuxc_gpr;
+ enum imx6_pcie_variants variant;
+ u32 tx_deemph_gen1;
+ u32 tx_deemph_gen2_3p5db;
+ u32 tx_deemph_gen2_6db;
+ u32 tx_swing_full;
+ u32 tx_swing_low;
+ int link_gen;
+};
+
+/* 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
+
+#define PCIE_RC_LCSR 0x80
+
+/* 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 PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0)
+
+#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(struct imx6_pcie *imx6_pcie, int exp_val)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ u32 val;
+ u32 max_iterations = 10;
+ u32 wait_counter = 0;
+
+ do {
+ val = dw_pcie_readl_dbi(pci, 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(struct imx6_pcie *imx6_pcie, int addr)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ u32 val;
+ int ret;
+
+ val = addr << PCIE_PHY_CTRL_DATA_LOC;
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
+
+ val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC);
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
+
+ ret = pcie_phy_poll_ack(imx6_pcie, 1);
+ if (ret)
+ return ret;
+
+ val = addr << PCIE_PHY_CTRL_DATA_LOC;
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
+
+ return pcie_phy_poll_ack(imx6_pcie, 0);
+}
+
+/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
+static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, int *data)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ u32 val, phy_ctl;
+ int ret;
+
+ ret = pcie_phy_wait_ack(imx6_pcie, addr);
+ if (ret)
+ return ret;
+
+ /* assert Read signal */
+ phy_ctl = 0x1 << PCIE_PHY_CTRL_RD_LOC;
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl);
+
+ ret = pcie_phy_poll_ack(imx6_pcie, 1);
+ if (ret)
+ return ret;
+
+ val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
+ *data = val & 0xffff;
+
+ /* deassert Read signal */
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00);
+
+ return pcie_phy_poll_ack(imx6_pcie, 0);
+}
+
+static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, int data)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ u32 var;
+ int ret;
+
+ /* write addr */
+ /* cap addr */
+ ret = pcie_phy_wait_ack(imx6_pcie, addr);
+ if (ret)
+ return ret;
+
+ var = data << PCIE_PHY_CTRL_DATA_LOC;
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
+
+ /* capture data */
+ var |= (0x1 << PCIE_PHY_CTRL_CAP_DAT_LOC);
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
+
+ ret = pcie_phy_poll_ack(imx6_pcie, 1);
+ if (ret)
+ return ret;
+
+ /* deassert cap data */
+ var = data << PCIE_PHY_CTRL_DATA_LOC;
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
+
+ /* wait for ack de-assertion */
+ ret = pcie_phy_poll_ack(imx6_pcie, 0);
+ if (ret)
+ return ret;
+
+ /* assert wr signal */
+ var = 0x1 << PCIE_PHY_CTRL_WR_LOC;
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
+
+ /* wait for ack */
+ ret = pcie_phy_poll_ack(imx6_pcie, 1);
+ if (ret)
+ return ret;
+
+ /* deassert wr signal */
+ var = data << PCIE_PHY_CTRL_DATA_LOC;
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
+
+ /* wait for ack de-assertion */
+ ret = pcie_phy_poll_ack(imx6_pcie, 0);
+ if (ret)
+ return ret;
+
+ dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0);
+
+ return 0;
+}
+
+static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
+{
+ u32 tmp;
+
+ pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
+ tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+ PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+ pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
+
+ usleep_range(2000, 3000);
+
+ pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
+ tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+ PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+ pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
+}
+
+/* Added for PCI abort handling */
+static int imx6q_pcie_abort_handler(unsigned long addr,
+ unsigned int fsr, struct pt_regs *regs)
+{
+ return 0;
+}
+
+static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
+{
- /*
- * 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 = dw_pcie_readl_dbi(pci, PCIE_PL_PFLR);
- val &= ~PCIE_PL_PFLR_LINK_STATE_MASK;
- val |= PCIE_PL_PFLR_FORCE_LINK;
- dw_pcie_writel_dbi(pci, PCIE_PL_PFLR, val);
-
- regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
- IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
- }
-
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
+ /* Force PCIe PHY reset */
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
+ IMX6SX_GPR5_PCIE_BTNRST_RESET,
+ IMX6SX_GPR5_PCIE_BTNRST_RESET);
+ break;
+ case IMX6QP:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_SW_RST,
+ IMX6Q_GPR1_PCIE_SW_RST);
+ break;
+ case IMX6Q:
- if (ret) {
- dev_info(dev, "Link never came up\n");
+ 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);
+ break;
+ }
+}
+
+static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct device *dev = pci->dev;
+ int ret = 0;
+
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
+ if (ret) {
+ dev_err(dev, "unable to enable pcie_axi clock\n");
+ break;
+ }
+
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
+ break;
+ case IMX6QP: /* FALLTHROUGH */
+ case IMX6Q:
+ /* 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);
+ break;
+ }
+
+ return ret;
+}
+
+static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct device *dev = pci->dev;
+ int ret;
+
+ ret = clk_prepare_enable(imx6_pcie->pcie_phy);
+ if (ret) {
+ dev_err(dev, "unable to enable pcie_phy clock\n");
+ return;
+ }
+
+ ret = clk_prepare_enable(imx6_pcie->pcie_bus);
+ if (ret) {
+ dev_err(dev, "unable to enable pcie_bus clock\n");
+ goto err_pcie_bus;
+ }
+
+ ret = clk_prepare_enable(imx6_pcie->pcie);
+ if (ret) {
+ dev_err(dev, "unable to enable pcie clock\n");
+ goto err_pcie;
+ }
+
+ ret = imx6_pcie_enable_ref_clk(imx6_pcie);
+ if (ret) {
+ dev_err(dev, "unable to enable pcie ref clock\n");
+ goto err_ref_clk;
+ }
+
+ /* 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_cansleep(imx6_pcie->reset_gpio,
+ imx6_pcie->gpio_active_high);
+ msleep(100);
+ gpio_set_value_cansleep(imx6_pcie->reset_gpio,
+ !imx6_pcie->gpio_active_high);
+ }
+
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
+ IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
+ break;
+ case IMX6QP:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
+ IMX6Q_GPR1_PCIE_SW_RST, 0);
+
+ usleep_range(200, 500);
+ break;
+ case IMX6Q: /* Nothing to do */
+ break;
+ }
+
+ return;
+
+err_ref_clk:
+ clk_disable_unprepare(imx6_pcie->pcie);
+err_pcie:
+ clk_disable_unprepare(imx6_pcie->pcie_bus);
+err_pcie_bus:
+ clk_disable_unprepare(imx6_pcie->pcie_phy);
+}
+
+static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
+{
+ if (imx6_pcie->variant == IMX6SX)
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_RX_EQ_MASK,
+ IMX6SX_GPR12_PCIE_RX_EQ_2);
+
+ 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,
+ imx6_pcie->tx_deemph_gen1 << 0);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
+ imx6_pcie->tx_deemph_gen2_3p5db << 6);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
+ imx6_pcie->tx_deemph_gen2_6db << 12);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_SWING_FULL,
+ imx6_pcie->tx_swing_full << 18);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
+ IMX6Q_GPR8_TX_SWING_LOW,
+ imx6_pcie->tx_swing_low << 25);
+}
+
+static int imx6_pcie_wait_for_link(struct imx6_pcie *imx6_pcie)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct device *dev = pci->dev;
+
+ /* check if the link is up or not */
+ if (!dw_pcie_wait_for_link(pci))
+ return 0;
+
+ dev_dbg(dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
+ dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R0),
+ dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1));
+ return -ETIMEDOUT;
+}
+
+static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct device *dev = pci->dev;
+ u32 tmp;
+ unsigned int retries;
+
+ for (retries = 0; retries < 200; retries++) {
+ tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
+ /* Test if the speed change finished. */
+ if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
+ return 0;
+ usleep_range(100, 1000);
+ }
+
+ dev_err(dev, "Speed change timeout\n");
+ return -EINVAL;
+}
+
+static irqreturn_t imx6_pcie_msi_handler(int irq, void *arg)
+{
+ struct imx6_pcie *imx6_pcie = arg;
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct pcie_port *pp = &pci->pp;
+
+ return dw_handle_msi_irq(pp);
+}
+
+static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct device *dev = pci->dev;
+ u32 tmp;
+ int ret;
+
+ /*
+ * 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 = dw_pcie_readl_dbi(pci, PCIE_RC_LCR);
+ tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+ tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1;
+ dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp);
+
+ /* Start LTSSM. */
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
+
+ ret = imx6_pcie_wait_for_link(imx6_pcie);
- }
++ if (ret)
+ goto err_reset_phy;
- dev_err(dev,
- "pcie_incbound_axi clock missing or invalid\n");
+
+ if (imx6_pcie->link_gen == 2) {
+ /* Allow Gen2 mode after the link is up. */
+ tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCR);
+ tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+ tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
+ dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp);
+ } else {
+ dev_info(dev, "Link: Gen2 disabled\n");
+ }
+
+ /*
+ * Start Directed Speed Change so the best possible speed both link
+ * partners support can be negotiated.
+ */
+ tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
+ tmp |= PORT_LOGIC_SPEED_CHANGE;
+ dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
+
+ ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
+ if (ret) {
+ dev_err(dev, "Failed to bring link up!\n");
+ goto err_reset_phy;
+ }
+
+ /* Make sure link training is finished as well! */
+ ret = imx6_pcie_wait_for_link(imx6_pcie);
+ if (ret) {
+ dev_err(dev, "Failed to bring link up!\n");
+ goto err_reset_phy;
+ }
+
+ tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCSR);
+ dev_info(dev, "Link up, Gen%i\n", (tmp >> 16) & 0xf);
+ return 0;
+
+err_reset_phy:
+ dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
+ dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R0),
+ dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1));
+ imx6_pcie_reset_phy(imx6_pcie);
+ return ret;
+}
+
+static void imx6_pcie_host_init(struct pcie_port *pp)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
+
+ imx6_pcie_assert_core_reset(imx6_pcie);
+ imx6_pcie_init_phy(imx6_pcie);
+ imx6_pcie_deassert_core_reset(imx6_pcie);
+ dw_pcie_setup_rc(pp);
+ imx6_pcie_establish_link(imx6_pcie);
+
+ if (IS_ENABLED(CONFIG_PCI_MSI))
+ dw_pcie_msi_init(pp);
+}
+
+static int imx6_pcie_link_up(struct dw_pcie *pci)
+{
+ return dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1) &
+ PCIE_PHY_DEBUG_R1_XMLH_LINK_UP;
+}
+
+static struct dw_pcie_host_ops imx6_pcie_host_ops = {
+ .host_init = imx6_pcie_host_init,
+};
+
+static int __init imx6_add_pcie_port(struct imx6_pcie *imx6_pcie,
+ struct platform_device *pdev)
+{
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct pcie_port *pp = &pci->pp;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ if (IS_ENABLED(CONFIG_PCI_MSI)) {
+ pp->msi_irq = platform_get_irq_byname(pdev, "msi");
+ if (pp->msi_irq <= 0) {
+ dev_err(dev, "failed to get MSI irq\n");
+ return -ENODEV;
+ }
+
+ ret = devm_request_irq(dev, pp->msi_irq,
+ imx6_pcie_msi_handler,
+ IRQF_SHARED | IRQF_NO_THREAD,
+ "mx6-pcie-msi", imx6_pcie);
+ if (ret) {
+ dev_err(dev, "failed to request MSI irq\n");
+ return ret;
+ }
+ }
+
+ pp->root_bus_nr = -1;
+ pp->ops = &imx6_pcie_host_ops;
+
+ ret = dw_pcie_host_init(pp);
+ if (ret) {
+ dev_err(dev, "failed to initialize host\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct dw_pcie_ops dw_pcie_ops = {
+ .link_up = imx6_pcie_link_up,
+};
+
+static int __init imx6_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct dw_pcie *pci;
+ struct imx6_pcie *imx6_pcie;
+ struct resource *dbi_base;
+ struct device_node *node = dev->of_node;
+ int ret;
+
+ imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
+ if (!imx6_pcie)
+ return -ENOMEM;
+
+ pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
+ if (!pci)
+ return -ENOMEM;
+
+ pci->dev = dev;
+ pci->ops = &dw_pcie_ops;
+
+ imx6_pcie->variant =
+ (enum imx6_pcie_variants)of_device_get_match_data(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);
+ pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
+ if (IS_ERR(pci->dbi_base))
+ return PTR_ERR(pci->dbi_base);
+
+ /* Fetch GPIOs */
+ imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
+ imx6_pcie->gpio_active_high = of_property_read_bool(node,
+ "reset-gpio-active-high");
+ if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+ ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
+ imx6_pcie->gpio_active_high ?
+ GPIOF_OUT_INIT_HIGH :
+ GPIOF_OUT_INIT_LOW,
+ "PCIe reset");
+ if (ret) {
+ dev_err(dev, "unable to get reset gpio\n");
+ return ret;
+ }
+ }
+
+ /* Fetch clocks */
+ imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
+ if (IS_ERR(imx6_pcie->pcie_phy)) {
+ dev_err(dev, "pcie_phy clock source missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie_phy);
+ }
+
+ imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
+ if (IS_ERR(imx6_pcie->pcie_bus)) {
+ dev_err(dev, "pcie_bus clock source missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie_bus);
+ }
+
+ imx6_pcie->pcie = devm_clk_get(dev, "pcie");
+ if (IS_ERR(imx6_pcie->pcie)) {
+ dev_err(dev, "pcie clock source missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie);
+ }
+
+ if (imx6_pcie->variant == IMX6SX) {
+ imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
+ "pcie_inbound_axi");
+ if (IS_ERR(imx6_pcie->pcie_inbound_axi)) {
++ dev_err(dev, "pcie_inbound_axi clock missing or invalid\n");
+ return PTR_ERR(imx6_pcie->pcie_inbound_axi);
+ }
+ }
+
+ /* 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(dev, "unable to find iomuxc registers\n");
+ return PTR_ERR(imx6_pcie->iomuxc_gpr);
+ }
+
+ /* Grab PCIe PHY Tx Settings */
+ if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
+ &imx6_pcie->tx_deemph_gen1))
+ imx6_pcie->tx_deemph_gen1 = 0;
+
+ if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
+ &imx6_pcie->tx_deemph_gen2_3p5db))
+ imx6_pcie->tx_deemph_gen2_3p5db = 0;
+
+ if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
+ &imx6_pcie->tx_deemph_gen2_6db))
+ imx6_pcie->tx_deemph_gen2_6db = 20;
+
+ if (of_property_read_u32(node, "fsl,tx-swing-full",
+ &imx6_pcie->tx_swing_full))
+ imx6_pcie->tx_swing_full = 127;
+
+ if (of_property_read_u32(node, "fsl,tx-swing-low",
+ &imx6_pcie->tx_swing_low))
+ imx6_pcie->tx_swing_low = 127;
+
+ /* Limit link speed */
+ ret = of_property_read_u32(node, "fsl,max-link-speed",
+ &imx6_pcie->link_gen);
+ if (ret)
+ imx6_pcie->link_gen = 1;
+
+ platform_set_drvdata(pdev, imx6_pcie);
+
+ ret = imx6_add_pcie_port(imx6_pcie, pdev);
+ if (ret < 0)
+ return ret;
+
+ 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);
+}
+
+static const struct of_device_id imx6_pcie_of_match[] = {
+ { .compatible = "fsl,imx6q-pcie", .data = (void *)IMX6Q, },
+ { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, },
+ { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, },
+ {},
+};
+
+static struct platform_driver imx6_pcie_driver = {
+ .driver = {
+ .name = "imx6q-pcie",
+ .of_match_table = imx6_pcie_of_match,
+ },
+ .shutdown = imx6_pcie_shutdown,
+};
+
+static int __init imx6_pcie_init(void)
+{
+ return platform_driver_probe(&imx6_pcie_driver, imx6_pcie_probe);
+}
+device_initcall(imx6_pcie_init);
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff