--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ *
+ * Author: Sumit Garg <sumit.garg@linaro.org>
+ */
+
+#include <asm/io.h>
+#include <asm-generic/gpio.h>
+#include <clk.h>
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <generic-phy.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/iopoll.h>
+#include <log.h>
+#include <pci.h>
+#include <power/regulator.h>
+#include <regmap.h>
+#include <reset.h>
+#include <syscon.h>
+#include <time.h>
+
+#include "pcie_dw_common.h"
+
+#define PCIE_LINK_CAPABILITY 0x7c
+#define TARGET_LINK_SPEED_MASK 0xf
+#define LINK_SPEED_GEN_1 0x1
+#define LINK_SPEED_GEN_2 0x2
+#define LINK_SPEED_GEN_3 0x3
+
+#define PCIE_MISC_CONTROL_1_OFF 0x8bc
+#define PCIE_DBI_RO_WR_EN BIT(0)
+
+#define PCIE_PORT_DEBUG0 0x728
+#define PCIE_PORT_DEBUG1 0x72c
+#define PCIE_PORT_DEBUG1_LINK_UP BIT(4)
+#define PCIE_PORT_DEBUG1_LINK_IN_TRAINING BIT(29)
+
+#define PCIE_LINK_UP_TIMEOUT_MS 100
+
+#define IOMUXC_GPR14_OFFSET 0x38
+#define IMX8M_GPR_PCIE_CLK_REQ_OVERRIDE_EN BIT(10)
+#define IMX8M_GPR_PCIE_CLK_REQ_OVERRIDE BIT(11)
+
+struct pcie_dw_imx {
+ /* Must be first member of the struct */
+ struct pcie_dw dw;
+ struct regmap *iomuxc_gpr;
+ struct clk_bulk clks;
+ struct gpio_desc reset_gpio;
+ struct reset_ctl apps_reset;
+ struct phy phy;
+ struct udevice *vpcie;
+};
+
+static void pcie_dw_configure(struct pcie_dw_imx *priv, u32 cap_speed)
+{
+ dw_pcie_dbi_write_enable(&priv->dw, true);
+
+ clrsetbits_le32(priv->dw.dbi_base + PCIE_LINK_CAPABILITY,
+ TARGET_LINK_SPEED_MASK, cap_speed);
+
+ dw_pcie_dbi_write_enable(&priv->dw, false);
+}
+
+static void imx_pcie_ltssm_enable(struct pcie_dw_imx *priv)
+{
+ reset_deassert(&priv->apps_reset);
+}
+
+static void imx_pcie_ltssm_disable(struct pcie_dw_imx *priv)
+{
+ reset_assert(&priv->apps_reset);
+}
+
+static bool is_link_up(u32 val)
+{
+ return ((val & PCIE_PORT_DEBUG1_LINK_UP) &&
+ (!(val & PCIE_PORT_DEBUG1_LINK_IN_TRAINING)));
+}
+
+static int wait_link_up(struct pcie_dw_imx *priv)
+{
+ u32 val;
+
+ return readl_poll_sleep_timeout(priv->dw.dbi_base + PCIE_PORT_DEBUG1,
+ val, is_link_up(val), 10000, 100000);
+}
+
+static int pcie_link_up(struct pcie_dw_imx *priv, u32 cap_speed)
+{
+ int ret;
+
+ /* DW pre link configurations */
+ pcie_dw_configure(priv, cap_speed);
+
+ /* Initiate link training */
+ imx_pcie_ltssm_enable(priv);
+
+ /* Check that link was established */
+ ret = wait_link_up(priv);
+ if (ret)
+ imx_pcie_ltssm_disable(priv);
+
+ return ret;
+}
+
+static int imx_pcie_assert_core_reset(struct pcie_dw_imx *priv)
+{
+ if (dm_gpio_is_valid(&priv->reset_gpio)) {
+ dm_gpio_set_value(&priv->reset_gpio, 1);
+ mdelay(20);
+ }
+
+ return reset_assert(&priv->apps_reset);
+}
+
+static int imx_pcie_clk_enable(struct pcie_dw_imx *priv)
+{
+ int ret;
+
+ ret = clk_enable_bulk(&priv->clks);
+ if (ret)
+ return ret;
+
+ /*
+ * Set the over ride low and enabled make sure that
+ * REF_CLK is turned on.
+ */
+ regmap_update_bits(priv->iomuxc_gpr, IOMUXC_GPR14_OFFSET,
+ IMX8M_GPR_PCIE_CLK_REQ_OVERRIDE, 0);
+ regmap_update_bits(priv->iomuxc_gpr, IOMUXC_GPR14_OFFSET,
+ IMX8M_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
+ IMX8M_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
+
+ /* allow the clocks to stabilize */
+ udelay(500);
+
+ return 0;
+}
+
+static void imx_pcie_deassert_core_reset(struct pcie_dw_imx *priv)
+{
+ if (!dm_gpio_is_valid(&priv->reset_gpio))
+ return;
+
+ mdelay(100);
+ dm_gpio_set_value(&priv->reset_gpio, 0);
+ /* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
+ mdelay(100);
+}
+
+static int pcie_dw_imx_probe(struct udevice *dev)
+{
+ struct pcie_dw_imx *priv = dev_get_priv(dev);
+ struct udevice *ctlr = pci_get_controller(dev);
+ struct pci_controller *hose = dev_get_uclass_priv(ctlr);
+ int ret;
+
+ if (priv->vpcie) {
+ ret = regulator_set_enable(priv->vpcie, true);
+ if (ret) {
+ dev_err(dev, "failed to enable vpcie regulator\n");
+ return ret;
+ }
+ }
+
+ ret = imx_pcie_assert_core_reset(priv);
+ if (ret) {
+ dev_err(dev, "failed to assert core reset\n");
+ return ret;
+ }
+
+ ret = imx_pcie_clk_enable(priv);
+ if (ret) {
+ dev_err(dev, "failed to enable clocks\n");
+ goto err_clk;
+ }
+
+ ret = generic_phy_init(&priv->phy);
+ if (ret) {
+ dev_err(dev, "failed to initialize PHY\n");
+ goto err_phy_init;
+ }
+
+ ret = generic_phy_power_on(&priv->phy);
+ if (ret) {
+ dev_err(dev, "failed to power on PHY\n");
+ goto err_phy_power;
+ }
+
+ imx_pcie_deassert_core_reset(priv);
+
+ priv->dw.first_busno = dev_seq(dev);
+ priv->dw.dev = dev;
+ pcie_dw_setup_host(&priv->dw);
+
+ if (pcie_link_up(priv, LINK_SPEED_GEN_1)) {
+ printf("PCIE-%d: Link down\n", dev_seq(dev));
+ ret = -ENODEV;
+ goto err_link;
+ }
+
+ printf("PCIE-%d: Link up (Gen%d-x%d, Bus%d)\n", dev_seq(dev),
+ pcie_dw_get_link_speed(&priv->dw),
+ pcie_dw_get_link_width(&priv->dw),
+ hose->first_busno);
+
+ pcie_dw_prog_outbound_atu_unroll(&priv->dw, PCIE_ATU_REGION_INDEX0,
+ PCIE_ATU_TYPE_MEM,
+ priv->dw.mem.phys_start,
+ priv->dw.mem.bus_start, priv->dw.mem.size);
+
+ return 0;
+
+err_link:
+ generic_shutdown_phy(&priv->phy);
+err_phy_power:
+ generic_phy_exit(&priv->phy);
+err_phy_init:
+ clk_disable_bulk(&priv->clks);
+err_clk:
+ imx_pcie_deassert_core_reset(priv);
+
+ return ret;
+}
+
+static int pcie_dw_imx_remove(struct udevice *dev)
+{
+ struct pcie_dw_imx *priv = dev_get_priv(dev);
+
+ generic_shutdown_phy(&priv->phy);
+ dm_gpio_free(dev, &priv->reset_gpio);
+ reset_free(&priv->apps_reset);
+ clk_release_bulk(&priv->clks);
+
+ return 0;
+}
+
+static int pcie_dw_imx_of_to_plat(struct udevice *dev)
+{
+ struct pcie_dw_imx *priv = dev_get_priv(dev);
+ ofnode gpr;
+ int ret;
+
+ /* Get the controller base address */
+ priv->dw.dbi_base = (void *)dev_read_addr_name(dev, "dbi");
+ if ((fdt_addr_t)priv->dw.dbi_base == FDT_ADDR_T_NONE) {
+ dev_err(dev, "failed to get dbi_base address\n");
+ return -EINVAL;
+ }
+
+ /* Get the config space base address and size */
+ priv->dw.cfg_base = (void *)dev_read_addr_size_name(dev, "config",
+ &priv->dw.cfg_size);
+ if ((fdt_addr_t)priv->dw.cfg_base == FDT_ADDR_T_NONE) {
+ dev_err(dev, "failed to get cfg_base address\n");
+ return -EINVAL;
+ }
+
+ ret = clk_get_bulk(dev, &priv->clks);
+ if (ret) {
+ dev_err(dev, "failed to get PCIe clks\n");
+ return ret;
+ }
+
+ ret = reset_get_by_name(dev, "apps", &priv->apps_reset);
+ if (ret) {
+ dev_err(dev,
+ "Failed to get PCIe apps reset control\n");
+ goto err_reset;
+ }
+
+ ret = gpio_request_by_name(dev, "reset-gpio", 0, &priv->reset_gpio,
+ GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE);
+ if (ret) {
+ dev_err(dev, "unable to get reset-gpio\n");
+ goto err_gpio;
+ }
+
+ ret = generic_phy_get_by_name(dev, "pcie-phy", &priv->phy);
+ if (ret) {
+ dev_err(dev, "failed to get pcie phy\n");
+ goto err_phy;
+ }
+
+ gpr = ofnode_by_compatible(ofnode_null(), "fsl,imx8mp-iomuxc-gpr");
+ if (ofnode_equal(gpr, ofnode_null())) {
+ dev_err(dev, "unable to find GPR node\n");
+ ret = -ENODEV;
+ goto err_phy;
+ }
+
+ priv->iomuxc_gpr = syscon_node_to_regmap(gpr);
+ if (IS_ERR(priv->iomuxc_gpr)) {
+ dev_err(dev, "unable to find iomuxc registers\n");
+ ret = PTR_ERR(priv->iomuxc_gpr);
+ goto err_phy;
+ }
+
+ /* vpcie-supply regulator is optional */
+ device_get_supply_regulator(dev, "vpcie-supply", &priv->vpcie);
+
+ return 0;
+
+err_phy:
+ dm_gpio_free(dev, &priv->reset_gpio);
+err_gpio:
+ reset_free(&priv->apps_reset);
+err_reset:
+ clk_release_bulk(&priv->clks);
+
+ return ret;
+}
+
+static const struct dm_pci_ops pcie_dw_imx_ops = {
+ .read_config = pcie_dw_read_config,
+ .write_config = pcie_dw_write_config,
+};
+
+static const struct udevice_id pcie_dw_imx_ids[] = {
+ { .compatible = "fsl,imx8mp-pcie" },
+ { }
+};
+
+U_BOOT_DRIVER(pcie_dw_imx) = {
+ .name = "pcie_dw_imx",
+ .id = UCLASS_PCI,
+ .of_match = pcie_dw_imx_ids,
+ .ops = &pcie_dw_imx_ops,
+ .of_to_plat = pcie_dw_imx_of_to_plat,
+ .probe = pcie_dw_imx_probe,
+ .remove = pcie_dw_imx_remove,
+ .priv_auto = sizeof(struct pcie_dw_imx),
+};
projects / u-boot.git / commitdiff
