--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Qualcomm PCIe Endpoint controller driver
+ *
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ * Author: Siddartha Mohanadoss <smohanad@codeaurora.org
+ *
+ * Copyright (c) 2021, Linaro Ltd.
+ * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mfd/syscon.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+#include "pcie-designware.h"
+
+/* PARF registers */
+#define PARF_SYS_CTRL 0x00
+#define PARF_DB_CTRL 0x10
+#define PARF_PM_CTRL 0x20
+#define PARF_MHI_BASE_ADDR_LOWER 0x178
+#define PARF_MHI_BASE_ADDR_UPPER 0x17c
+#define PARF_DEBUG_INT_EN 0x190
+#define PARF_AXI_MSTR_RD_HALT_NO_WRITES 0x1a4
+#define PARF_AXI_MSTR_WR_ADDR_HALT 0x1a8
+#define PARF_Q2A_FLUSH 0x1ac
+#define PARF_LTSSM 0x1b0
+#define PARF_CFG_BITS 0x210
+#define PARF_INT_ALL_STATUS 0x224
+#define PARF_INT_ALL_CLEAR 0x228
+#define PARF_INT_ALL_MASK 0x22c
+#define PARF_SLV_ADDR_MSB_CTRL 0x2c0
+#define PARF_DBI_BASE_ADDR 0x350
+#define PARF_DBI_BASE_ADDR_HI 0x354
+#define PARF_SLV_ADDR_SPACE_SIZE 0x358
+#define PARF_SLV_ADDR_SPACE_SIZE_HI 0x35c
+#define PARF_ATU_BASE_ADDR 0x634
+#define PARF_ATU_BASE_ADDR_HI 0x638
+#define PARF_SRIS_MODE 0x644
+#define PARF_DEVICE_TYPE 0x1000
+#define PARF_BDF_TO_SID_CFG 0x2c00
+
+/* PARF_INT_ALL_{STATUS/CLEAR/MASK} register fields */
+#define PARF_INT_ALL_LINK_DOWN BIT(1)
+#define PARF_INT_ALL_BME BIT(2)
+#define PARF_INT_ALL_PM_TURNOFF BIT(3)
+#define PARF_INT_ALL_DEBUG BIT(4)
+#define PARF_INT_ALL_LTR BIT(5)
+#define PARF_INT_ALL_MHI_Q6 BIT(6)
+#define PARF_INT_ALL_MHI_A7 BIT(7)
+#define PARF_INT_ALL_DSTATE_CHANGE BIT(8)
+#define PARF_INT_ALL_L1SUB_TIMEOUT BIT(9)
+#define PARF_INT_ALL_MMIO_WRITE BIT(10)
+#define PARF_INT_ALL_CFG_WRITE BIT(11)
+#define PARF_INT_ALL_BRIDGE_FLUSH_N BIT(12)
+#define PARF_INT_ALL_LINK_UP BIT(13)
+#define PARF_INT_ALL_AER_LEGACY BIT(14)
+#define PARF_INT_ALL_PLS_ERR BIT(15)
+#define PARF_INT_ALL_PME_LEGACY BIT(16)
+#define PARF_INT_ALL_PLS_PME BIT(17)
+
+/* PARF_BDF_TO_SID_CFG register fields */
+#define PARF_BDF_TO_SID_BYPASS BIT(0)
+
+/* PARF_DEBUG_INT_EN register fields */
+#define PARF_DEBUG_INT_PM_DSTATE_CHANGE BIT(1)
+#define PARF_DEBUG_INT_CFG_BUS_MASTER_EN BIT(2)
+#define PARF_DEBUG_INT_RADM_PM_TURNOFF BIT(3)
+
+/* PARF_DEVICE_TYPE register fields */
+#define PARF_DEVICE_TYPE_EP 0x0
+
+/* PARF_PM_CTRL register fields */
+#define PARF_PM_CTRL_REQ_EXIT_L1 BIT(1)
+#define PARF_PM_CTRL_READY_ENTR_L23 BIT(2)
+#define PARF_PM_CTRL_REQ_NOT_ENTR_L1 BIT(5)
+
+/* PARF_AXI_MSTR_RD_HALT_NO_WRITES register fields */
+#define PARF_AXI_MSTR_RD_HALT_NO_WRITE_EN BIT(0)
+
+/* PARF_AXI_MSTR_WR_ADDR_HALT register fields */
+#define PARF_AXI_MSTR_WR_ADDR_HALT_EN BIT(31)
+
+/* PARF_Q2A_FLUSH register fields */
+#define PARF_Q2A_FLUSH_EN BIT(16)
+
+/* PARF_SYS_CTRL register fields */
+#define PARF_SYS_CTRL_AUX_PWR_DET BIT(4)
+#define PARF_SYS_CTRL_CORE_CLK_CGC_DIS BIT(6)
+#define PARF_SYS_CTRL_SLV_DBI_WAKE_DISABLE BIT(11)
+
+/* PARF_DB_CTRL register fields */
+#define PARF_DB_CTRL_INSR_DBNCR_BLOCK BIT(0)
+#define PARF_DB_CTRL_RMVL_DBNCR_BLOCK BIT(1)
+#define PARF_DB_CTRL_DBI_WKP_BLOCK BIT(4)
+#define PARF_DB_CTRL_SLV_WKP_BLOCK BIT(5)
+#define PARF_DB_CTRL_MST_WKP_BLOCK BIT(6)
+
+/* PARF_CFG_BITS register fields */
+#define PARF_CFG_BITS_REQ_EXIT_L1SS_MSI_LTR_EN BIT(1)
+
+/* ELBI registers */
+#define ELBI_SYS_STTS 0x08
+
+/* DBI registers */
+#define DBI_CON_STATUS 0x44
+
+/* DBI register fields */
+#define DBI_CON_STATUS_POWER_STATE_MASK GENMASK(1, 0)
+
+#define XMLH_LINK_UP 0x400
+#define CORE_RESET_TIME_US_MIN 1000
+#define CORE_RESET_TIME_US_MAX 1005
+#define WAKE_DELAY_US 2000 /* 2 ms */
+
+#define to_pcie_ep(x) dev_get_drvdata((x)->dev)
+
+enum qcom_pcie_ep_link_status {
+ QCOM_PCIE_EP_LINK_DISABLED,
+ QCOM_PCIE_EP_LINK_ENABLED,
+ QCOM_PCIE_EP_LINK_UP,
+ QCOM_PCIE_EP_LINK_DOWN,
+};
+
+static struct clk_bulk_data qcom_pcie_ep_clks[] = {
+ { .id = "cfg" },
+ { .id = "aux" },
+ { .id = "bus_master" },
+ { .id = "bus_slave" },
+ { .id = "ref" },
+ { .id = "sleep" },
+ { .id = "slave_q2a" },
+};
+
+struct qcom_pcie_ep {
+ struct dw_pcie pci;
+
+ void __iomem *parf;
+ void __iomem *elbi;
+ struct regmap *perst_map;
+ struct resource *mmio_res;
+
+ struct reset_control *core_reset;
+ struct gpio_desc *reset;
+ struct gpio_desc *wake;
+ struct phy *phy;
+
+ u32 perst_en;
+ u32 perst_sep_en;
+
+ enum qcom_pcie_ep_link_status link_status;
+ int global_irq;
+ int perst_irq;
+};
+
+static int qcom_pcie_ep_core_reset(struct qcom_pcie_ep *pcie_ep)
+{
+ struct dw_pcie *pci = &pcie_ep->pci;
+ struct device *dev = pci->dev;
+ int ret;
+
+ ret = reset_control_assert(pcie_ep->core_reset);
+ if (ret) {
+ dev_err(dev, "Cannot assert core reset\n");
+ return ret;
+ }
+
+ usleep_range(CORE_RESET_TIME_US_MIN, CORE_RESET_TIME_US_MAX);
+
+ ret = reset_control_deassert(pcie_ep->core_reset);
+ if (ret) {
+ dev_err(dev, "Cannot de-assert core reset\n");
+ return ret;
+ }
+
+ usleep_range(CORE_RESET_TIME_US_MIN, CORE_RESET_TIME_US_MAX);
+
+ return 0;
+}
+
+/*
+ * Delatch PERST_EN and PERST_SEPARATION_ENABLE with TCSR to avoid
+ * device reset during host reboot and hibernation. The driver is
+ * expected to handle this situation.
+ */
+static void qcom_pcie_ep_configure_tcsr(struct qcom_pcie_ep *pcie_ep)
+{
+ regmap_write(pcie_ep->perst_map, pcie_ep->perst_en, 0);
+ regmap_write(pcie_ep->perst_map, pcie_ep->perst_sep_en, 0);
+}
+
+static int qcom_pcie_dw_link_up(struct dw_pcie *pci)
+{
+ struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
+ u32 reg;
+
+ reg = readl_relaxed(pcie_ep->elbi + ELBI_SYS_STTS);
+
+ return reg & XMLH_LINK_UP;
+}
+
+static int qcom_pcie_dw_start_link(struct dw_pcie *pci)
+{
+ struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
+
+ enable_irq(pcie_ep->perst_irq);
+
+ return 0;
+}
+
+static void qcom_pcie_dw_stop_link(struct dw_pcie *pci)
+{
+ struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
+
+ disable_irq(pcie_ep->perst_irq);
+}
+
+static int qcom_pcie_perst_deassert(struct dw_pcie *pci)
+{
+ struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
+ struct device *dev = pci->dev;
+ u32 val, offset;
+ int ret;
+
+ ret = clk_bulk_prepare_enable(ARRAY_SIZE(qcom_pcie_ep_clks),
+ qcom_pcie_ep_clks);
+ if (ret)
+ return ret;
+
+ ret = qcom_pcie_ep_core_reset(pcie_ep);
+ if (ret)
+ goto err_disable_clk;
+
+ ret = phy_init(pcie_ep->phy);
+ if (ret)
+ goto err_disable_clk;
+
+ ret = phy_power_on(pcie_ep->phy);
+ if (ret)
+ goto err_phy_exit;
+
+ /* Assert WAKE# to RC to indicate device is ready */
+ gpiod_set_value_cansleep(pcie_ep->wake, 1);
+ usleep_range(WAKE_DELAY_US, WAKE_DELAY_US + 500);
+ gpiod_set_value_cansleep(pcie_ep->wake, 0);
+
+ qcom_pcie_ep_configure_tcsr(pcie_ep);
+
+ /* Disable BDF to SID mapping */
+ val = readl_relaxed(pcie_ep->parf + PARF_BDF_TO_SID_CFG);
+ val |= PARF_BDF_TO_SID_BYPASS;
+ writel_relaxed(val, pcie_ep->parf + PARF_BDF_TO_SID_CFG);
+
+ /* Enable debug IRQ */
+ val = readl_relaxed(pcie_ep->parf + PARF_DEBUG_INT_EN);
+ val |= PARF_DEBUG_INT_RADM_PM_TURNOFF |
+ PARF_DEBUG_INT_CFG_BUS_MASTER_EN |
+ PARF_DEBUG_INT_PM_DSTATE_CHANGE;
+ writel_relaxed(val, pcie_ep->parf + PARF_DEBUG_INT_EN);
+
+ /* Configure PCIe to endpoint mode */
+ writel_relaxed(PARF_DEVICE_TYPE_EP, pcie_ep->parf + PARF_DEVICE_TYPE);
+
+ /* Allow entering L1 state */
+ val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
+ val &= ~PARF_PM_CTRL_REQ_NOT_ENTR_L1;
+ writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
+
+ /* Read halts write */
+ val = readl_relaxed(pcie_ep->parf + PARF_AXI_MSTR_RD_HALT_NO_WRITES);
+ val &= ~PARF_AXI_MSTR_RD_HALT_NO_WRITE_EN;
+ writel_relaxed(val, pcie_ep->parf + PARF_AXI_MSTR_RD_HALT_NO_WRITES);
+
+ /* Write after write halt */
+ val = readl_relaxed(pcie_ep->parf + PARF_AXI_MSTR_WR_ADDR_HALT);
+ val |= PARF_AXI_MSTR_WR_ADDR_HALT_EN;
+ writel_relaxed(val, pcie_ep->parf + PARF_AXI_MSTR_WR_ADDR_HALT);
+
+ /* Q2A flush disable */
+ val = readl_relaxed(pcie_ep->parf + PARF_Q2A_FLUSH);
+ val &= ~PARF_Q2A_FLUSH_EN;
+ writel_relaxed(val, pcie_ep->parf + PARF_Q2A_FLUSH);
+
+ /* Disable DBI Wakeup, core clock CGC and enable AUX power */
+ val = readl_relaxed(pcie_ep->parf + PARF_SYS_CTRL);
+ val |= PARF_SYS_CTRL_SLV_DBI_WAKE_DISABLE |
+ PARF_SYS_CTRL_CORE_CLK_CGC_DIS |
+ PARF_SYS_CTRL_AUX_PWR_DET;
+ writel_relaxed(val, pcie_ep->parf + PARF_SYS_CTRL);
+
+ /* Disable the debouncers */
+ val = readl_relaxed(pcie_ep->parf + PARF_DB_CTRL);
+ val |= PARF_DB_CTRL_INSR_DBNCR_BLOCK | PARF_DB_CTRL_RMVL_DBNCR_BLOCK |
+ PARF_DB_CTRL_DBI_WKP_BLOCK | PARF_DB_CTRL_SLV_WKP_BLOCK |
+ PARF_DB_CTRL_MST_WKP_BLOCK;
+ writel_relaxed(val, pcie_ep->parf + PARF_DB_CTRL);
+
+ /* Request to exit from L1SS for MSI and LTR MSG */
+ val = readl_relaxed(pcie_ep->parf + PARF_CFG_BITS);
+ val |= PARF_CFG_BITS_REQ_EXIT_L1SS_MSI_LTR_EN;
+ writel_relaxed(val, pcie_ep->parf + PARF_CFG_BITS);
+
+ dw_pcie_dbi_ro_wr_en(pci);
+
+ /* Set the L0s Exit Latency to 2us-4us = 0x6 */
+ offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+ val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
+ val &= ~PCI_EXP_LNKCAP_L0SEL;
+ val |= FIELD_PREP(PCI_EXP_LNKCAP_L0SEL, 0x6);
+ dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, val);
+
+ /* Set the L1 Exit Latency to be 32us-64 us = 0x6 */
+ offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+ val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
+ val &= ~PCI_EXP_LNKCAP_L1EL;
+ val |= FIELD_PREP(PCI_EXP_LNKCAP_L1EL, 0x6);
+ dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, val);
+
+ dw_pcie_dbi_ro_wr_dis(pci);
+
+ writel_relaxed(0, pcie_ep->parf + PARF_INT_ALL_MASK);
+ val = PARF_INT_ALL_LINK_DOWN | PARF_INT_ALL_BME |
+ PARF_INT_ALL_PM_TURNOFF | PARF_INT_ALL_DSTATE_CHANGE |
+ PARF_INT_ALL_LINK_UP;
+ writel_relaxed(val, pcie_ep->parf + PARF_INT_ALL_MASK);
+
+ ret = dw_pcie_ep_init_complete(&pcie_ep->pci.ep);
+ if (ret) {
+ dev_err(dev, "Failed to complete initialization: %d\n", ret);
+ goto err_phy_power_off;
+ }
+
+ /*
+ * The physical address of the MMIO region which is exposed as the BAR
+ * should be written to MHI BASE registers.
+ */
+ writel_relaxed(pcie_ep->mmio_res->start,
+ pcie_ep->parf + PARF_MHI_BASE_ADDR_LOWER);
+ writel_relaxed(0, pcie_ep->parf + PARF_MHI_BASE_ADDR_UPPER);
+
+ dw_pcie_ep_init_notify(&pcie_ep->pci.ep);
+
+ /* Enable LTSSM */
+ val = readl_relaxed(pcie_ep->parf + PARF_LTSSM);
+ val |= BIT(8);
+ writel_relaxed(val, pcie_ep->parf + PARF_LTSSM);
+
+ return 0;
+
+err_phy_power_off:
+ phy_power_off(pcie_ep->phy);
+err_phy_exit:
+ phy_exit(pcie_ep->phy);
+err_disable_clk:
+ clk_bulk_disable_unprepare(ARRAY_SIZE(qcom_pcie_ep_clks),
+ qcom_pcie_ep_clks);
+
+ return ret;
+}
+
+static void qcom_pcie_perst_assert(struct dw_pcie *pci)
+{
+ struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
+ struct device *dev = pci->dev;
+
+ if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED) {
+ dev_dbg(dev, "Link is already disabled\n");
+ return;
+ }
+
+ phy_power_off(pcie_ep->phy);
+ phy_exit(pcie_ep->phy);
+ clk_bulk_disable_unprepare(ARRAY_SIZE(qcom_pcie_ep_clks),
+ qcom_pcie_ep_clks);
+ pcie_ep->link_status = QCOM_PCIE_EP_LINK_DISABLED;
+}
+
+/* Common DWC controller ops */
+static const struct dw_pcie_ops pci_ops = {
+ .link_up = qcom_pcie_dw_link_up,
+ .start_link = qcom_pcie_dw_start_link,
+ .stop_link = qcom_pcie_dw_stop_link,
+};
+
+static int qcom_pcie_ep_get_io_resources(struct platform_device *pdev,
+ struct qcom_pcie_ep *pcie_ep)
+{
+ struct device *dev = &pdev->dev;
+ struct dw_pcie *pci = &pcie_ep->pci;
+ struct device_node *syscon;
+ struct resource *res;
+ int ret;
+
+ pcie_ep->parf = devm_platform_ioremap_resource_byname(pdev, "parf");
+ if (IS_ERR(pcie_ep->parf))
+ return PTR_ERR(pcie_ep->parf);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
+ pci->dbi_base = devm_pci_remap_cfg_resource(dev, res);
+ if (IS_ERR(pci->dbi_base))
+ return PTR_ERR(pci->dbi_base);
+ pci->dbi_base2 = pci->dbi_base;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi");
+ pcie_ep->elbi = devm_pci_remap_cfg_resource(dev, res);
+ if (IS_ERR(pcie_ep->elbi))
+ return PTR_ERR(pcie_ep->elbi);
+
+ pcie_ep->mmio_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "mmio");
+
+ syscon = of_parse_phandle(dev->of_node, "qcom,perst-regs", 0);
+ if (!syscon) {
+ dev_err(dev, "Failed to parse qcom,perst-regs\n");
+ return -EINVAL;
+ }
+
+ pcie_ep->perst_map = syscon_node_to_regmap(syscon);
+ of_node_put(syscon);
+ if (IS_ERR(pcie_ep->perst_map))
+ return PTR_ERR(pcie_ep->perst_map);
+
+ ret = of_property_read_u32_index(dev->of_node, "qcom,perst-regs",
+ 1, &pcie_ep->perst_en);
+ if (ret < 0) {
+ dev_err(dev, "No Perst Enable offset in syscon\n");
+ return ret;
+ }
+
+ ret = of_property_read_u32_index(dev->of_node, "qcom,perst-regs",
+ 2, &pcie_ep->perst_sep_en);
+ if (ret < 0) {
+ dev_err(dev, "No Perst Separation Enable offset in syscon\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int qcom_pcie_ep_get_resources(struct platform_device *pdev,
+ struct qcom_pcie_ep *pcie_ep)
+{
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ ret = qcom_pcie_ep_get_io_resources(pdev, pcie_ep);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to get io resources %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_clk_bulk_get(dev, ARRAY_SIZE(qcom_pcie_ep_clks),
+ qcom_pcie_ep_clks);
+ if (ret)
+ return ret;
+
+ pcie_ep->core_reset = devm_reset_control_get_exclusive(dev, "core");
+ if (IS_ERR(pcie_ep->core_reset))
+ return PTR_ERR(pcie_ep->core_reset);
+
+ pcie_ep->reset = devm_gpiod_get(dev, "reset", GPIOD_IN);
+ if (IS_ERR(pcie_ep->reset))
+ return PTR_ERR(pcie_ep->reset);
+
+ pcie_ep->wake = devm_gpiod_get_optional(dev, "wake", GPIOD_OUT_LOW);
+ if (IS_ERR(pcie_ep->wake))
+ return PTR_ERR(pcie_ep->wake);
+
+ pcie_ep->phy = devm_phy_optional_get(&pdev->dev, "pciephy");
+ if (IS_ERR(pcie_ep->phy))
+ ret = PTR_ERR(pcie_ep->phy);
+
+ return ret;
+}
+
+/* TODO: Notify clients about PCIe state change */
+static irqreturn_t qcom_pcie_ep_global_irq_thread(int irq, void *data)
+{
+ struct qcom_pcie_ep *pcie_ep = data;
+ struct dw_pcie *pci = &pcie_ep->pci;
+ struct device *dev = pci->dev;
+ u32 status = readl_relaxed(pcie_ep->parf + PARF_INT_ALL_STATUS);
+ u32 mask = readl_relaxed(pcie_ep->parf + PARF_INT_ALL_MASK);
+ u32 dstate, val;
+
+ writel_relaxed(status, pcie_ep->parf + PARF_INT_ALL_CLEAR);
+ status &= mask;
+
+ if (FIELD_GET(PARF_INT_ALL_LINK_DOWN, status)) {
+ dev_dbg(dev, "Received Linkdown event\n");
+ pcie_ep->link_status = QCOM_PCIE_EP_LINK_DOWN;
+ } else if (FIELD_GET(PARF_INT_ALL_BME, status)) {
+ dev_dbg(dev, "Received BME event. Link is enabled!\n");
+ pcie_ep->link_status = QCOM_PCIE_EP_LINK_ENABLED;
+ } else if (FIELD_GET(PARF_INT_ALL_PM_TURNOFF, status)) {
+ dev_dbg(dev, "Received PM Turn-off event! Entering L23\n");
+ val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
+ val |= PARF_PM_CTRL_READY_ENTR_L23;
+ writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
+ } else if (FIELD_GET(PARF_INT_ALL_DSTATE_CHANGE, status)) {
+ dstate = dw_pcie_readl_dbi(pci, DBI_CON_STATUS) &
+ DBI_CON_STATUS_POWER_STATE_MASK;
+ dev_dbg(dev, "Received D%d state event\n", dstate);
+ if (dstate == 3) {
+ val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
+ val |= PARF_PM_CTRL_REQ_EXIT_L1;
+ writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
+ }
+ } else if (FIELD_GET(PARF_INT_ALL_LINK_UP, status)) {
+ dev_dbg(dev, "Received Linkup event. Enumeration complete!\n");
+ dw_pcie_ep_linkup(&pci->ep);
+ pcie_ep->link_status = QCOM_PCIE_EP_LINK_UP;
+ } else {
+ dev_dbg(dev, "Received unknown event: %d\n", status);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t qcom_pcie_ep_perst_irq_thread(int irq, void *data)
+{
+ struct qcom_pcie_ep *pcie_ep = data;
+ struct dw_pcie *pci = &pcie_ep->pci;
+ struct device *dev = pci->dev;
+ u32 perst;
+
+ perst = gpiod_get_value(pcie_ep->reset);
+ if (perst) {
+ dev_dbg(dev, "PERST asserted by host. Shutting down the PCIe link!\n");
+ qcom_pcie_perst_assert(pci);
+ } else {
+ dev_dbg(dev, "PERST de-asserted by host. Starting link training!\n");
+ qcom_pcie_perst_deassert(pci);
+ }
+
+ irq_set_irq_type(gpiod_to_irq(pcie_ep->reset),
+ (perst ? IRQF_TRIGGER_HIGH : IRQF_TRIGGER_LOW));
+
+ return IRQ_HANDLED;
+}
+
+static int qcom_pcie_ep_enable_irq_resources(struct platform_device *pdev,
+ struct qcom_pcie_ep *pcie_ep)
+{
+ int irq, ret;
+
+ irq = platform_get_irq_byname(pdev, "global");
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Failed to get Global IRQ\n");
+ return irq;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+ qcom_pcie_ep_global_irq_thread,
+ IRQF_ONESHOT,
+ "global_irq", pcie_ep);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request Global IRQ\n");
+ return ret;
+ }
+
+ pcie_ep->perst_irq = gpiod_to_irq(pcie_ep->reset);
+ irq_set_status_flags(pcie_ep->perst_irq, IRQ_NOAUTOEN);
+ ret = devm_request_threaded_irq(&pdev->dev, pcie_ep->perst_irq, NULL,
+ qcom_pcie_ep_perst_irq_thread,
+ IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+ "perst_irq", pcie_ep);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request PERST IRQ\n");
+ disable_irq(irq);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int qcom_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
+ enum pci_epc_irq_type type, u16 interrupt_num)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ switch (type) {
+ case PCI_EPC_IRQ_LEGACY:
+ return dw_pcie_ep_raise_legacy_irq(ep, func_no);
+ case PCI_EPC_IRQ_MSI:
+ return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
+ default:
+ dev_err(pci->dev, "Unknown IRQ type\n");
+ return -EINVAL;
+ }
+}
+
+static const struct pci_epc_features qcom_pcie_epc_features = {
+ .linkup_notifier = true,
+ .core_init_notifier = true,
+ .msi_capable = true,
+ .msix_capable = false,
+};
+
+static const struct pci_epc_features *
+qcom_pcie_epc_get_features(struct dw_pcie_ep *pci_ep)
+{
+ return &qcom_pcie_epc_features;
+}
+
+static void qcom_pcie_ep_init(struct dw_pcie_ep *ep)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ enum pci_barno bar;
+
+ for (bar = BAR_0; bar <= BAR_5; bar++)
+ dw_pcie_ep_reset_bar(pci, bar);
+}
+
+static struct dw_pcie_ep_ops pci_ep_ops = {
+ .ep_init = qcom_pcie_ep_init,
+ .raise_irq = qcom_pcie_ep_raise_irq,
+ .get_features = qcom_pcie_epc_get_features,
+};
+
+static int qcom_pcie_ep_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct qcom_pcie_ep *pcie_ep;
+ int ret;
+
+ pcie_ep = devm_kzalloc(dev, sizeof(*pcie_ep), GFP_KERNEL);
+ if (!pcie_ep)
+ return -ENOMEM;
+
+ pcie_ep->pci.dev = dev;
+ pcie_ep->pci.ops = &pci_ops;
+ pcie_ep->pci.ep.ops = &pci_ep_ops;
+ platform_set_drvdata(pdev, pcie_ep);
+
+ ret = qcom_pcie_ep_get_resources(pdev, pcie_ep);
+ if (ret)
+ return ret;
+
+ ret = clk_bulk_prepare_enable(ARRAY_SIZE(qcom_pcie_ep_clks),
+ qcom_pcie_ep_clks);
+ if (ret)
+ return ret;
+
+ ret = qcom_pcie_ep_core_reset(pcie_ep);
+ if (ret)
+ goto err_disable_clk;
+
+ ret = phy_init(pcie_ep->phy);
+ if (ret)
+ goto err_disable_clk;
+
+ /* PHY needs to be powered on for dw_pcie_ep_init() */
+ ret = phy_power_on(pcie_ep->phy);
+ if (ret)
+ goto err_phy_exit;
+
+ ret = dw_pcie_ep_init(&pcie_ep->pci.ep);
+ if (ret) {
+ dev_err(dev, "Failed to initialize endpoint: %d\n", ret);
+ goto err_phy_power_off;
+ }
+
+ ret = qcom_pcie_ep_enable_irq_resources(pdev, pcie_ep);
+ if (ret)
+ goto err_phy_power_off;
+
+ return 0;
+
+err_phy_power_off:
+ phy_power_off(pcie_ep->phy);
+err_phy_exit:
+ phy_exit(pcie_ep->phy);
+err_disable_clk:
+ clk_bulk_disable_unprepare(ARRAY_SIZE(qcom_pcie_ep_clks),
+ qcom_pcie_ep_clks);
+
+ return ret;
+}
+
+static int qcom_pcie_ep_remove(struct platform_device *pdev)
+{
+ struct qcom_pcie_ep *pcie_ep = platform_get_drvdata(pdev);
+
+ if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED)
+ return 0;
+
+ phy_power_off(pcie_ep->phy);
+ phy_exit(pcie_ep->phy);
+ clk_bulk_disable_unprepare(ARRAY_SIZE(qcom_pcie_ep_clks),
+ qcom_pcie_ep_clks);
+
+ return 0;
+}
+
+static const struct of_device_id qcom_pcie_ep_match[] = {
+ { .compatible = "qcom,sdx55-pcie-ep", },
+ { }
+};
+
+static struct platform_driver qcom_pcie_ep_driver = {
+ .probe = qcom_pcie_ep_probe,
+ .remove = qcom_pcie_ep_remove,
+ .driver = {
+ .name = "qcom-pcie-ep",
+ .of_match_table = qcom_pcie_ep_match,
+ },
+};
+builtin_platform_driver(qcom_pcie_ep_driver);
+
+MODULE_AUTHOR("Siddartha Mohanadoss <smohanad@codeaurora.org>");
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
+MODULE_DESCRIPTION("Qualcomm PCIe Endpoint controller driver");
+MODULE_LICENSE("GPL v2");
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