diff options
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-qcom-ep.c')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-qcom-ep.c | 836 |
1 files changed, 836 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/controller/dwc/pcie-qcom-ep.c new file mode 100644 index 000000000..1c7fd05ce --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c @@ -0,0 +1,836 @@ +// 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/debugfs.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 <linux/module.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_CLOCK_RESET_CTRL 0x174 +#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_DEBUG_CNT_PM_LINKST_IN_L2 0xc04 +#define PARF_DEBUG_CNT_PM_LINKST_IN_L1 0xc0c +#define PARF_DEBUG_CNT_PM_LINKST_IN_L0S 0xc10 +#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1 0xc84 +#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2 0xc88 +#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_MHI_CLOCK_RESET_CTRL fields */ +#define PARF_MSTR_AXI_CLK_EN BIT(1) + +/* 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_MSTR_ACLK_CGC_DIS BIT(10) +#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 +#define ELBI_CS2_ENABLE 0xa4 + +/* 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, +}; + +/** + * struct qcom_pcie_ep - Qualcomm PCIe Endpoint Controller + * @pci: Designware PCIe controller struct + * @parf: Qualcomm PCIe specific PARF register base + * @elbi: Designware PCIe specific ELBI register base + * @mmio: MMIO register base + * @perst_map: PERST regmap + * @mmio_res: MMIO region resource + * @core_reset: PCIe Endpoint core reset + * @reset: PERST# GPIO + * @wake: WAKE# GPIO + * @phy: PHY controller block + * @debugfs: PCIe Endpoint Debugfs directory + * @clks: PCIe clocks + * @num_clks: PCIe clocks count + * @perst_en: Flag for PERST enable + * @perst_sep_en: Flag for PERST separation enable + * @link_status: PCIe Link status + * @global_irq: Qualcomm PCIe specific Global IRQ + * @perst_irq: PERST# IRQ + */ +struct qcom_pcie_ep { + struct dw_pcie pci; + + void __iomem *parf; + void __iomem *elbi; + void __iomem *mmio; + struct regmap *perst_map; + struct resource *mmio_res; + + struct reset_control *core_reset; + struct gpio_desc *reset; + struct gpio_desc *wake; + struct phy *phy; + struct dentry *debugfs; + + struct clk_bulk_data *clks; + int num_clks; + + 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) +{ + if (pcie_ep->perst_map) { + 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 void qcom_pcie_dw_write_dbi2(struct dw_pcie *pci, void __iomem *base, + u32 reg, size_t size, u32 val) +{ + struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci); + int ret; + + writel(1, pcie_ep->elbi + ELBI_CS2_ENABLE); + + ret = dw_pcie_write(pci->dbi_base2 + reg, size, val); + if (ret) + dev_err(pci->dev, "Failed to write DBI2 register (0x%x): %d\n", reg, ret); + + writel(0, pcie_ep->elbi + ELBI_CS2_ENABLE); +} + +static int qcom_pcie_enable_resources(struct qcom_pcie_ep *pcie_ep) +{ + int ret; + + ret = clk_bulk_prepare_enable(pcie_ep->num_clks, 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; + + return 0; + +err_phy_exit: + phy_exit(pcie_ep->phy); +err_disable_clk: + clk_bulk_disable_unprepare(pcie_ep->num_clks, pcie_ep->clks); + + return ret; +} + +static void qcom_pcie_disable_resources(struct qcom_pcie_ep *pcie_ep) +{ + phy_power_off(pcie_ep->phy); + phy_exit(pcie_ep->phy); + clk_bulk_disable_unprepare(pcie_ep->num_clks, pcie_ep->clks); +} + +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 = qcom_pcie_enable_resources(pcie_ep); + if (ret) { + dev_err(dev, "Failed to enable resources: %d\n", ret); + return ret; + } + + /* 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 Master AXI clock during idle. Do not allow DBI access + * to take the core out of L1. Disable core clock gating that + * gates PIPE clock from propagating to core clock. Report to the + * host that Vaux is present. + */ + val = readl_relaxed(pcie_ep->parf + PARF_SYS_CTRL); + val &= ~PARF_SYS_CTRL_MSTR_ACLK_CGC_DIS; + 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_disable_resources; + } + + /* + * 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); + + /* Gate Master AXI clock to MHI bus during L1SS */ + val = readl_relaxed(pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL); + val &= ~PARF_MSTR_AXI_CLK_EN; + writel_relaxed(val, pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL); + + 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_disable_resources: + qcom_pcie_disable_resources(pcie_ep); + + 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; + } + + qcom_pcie_disable_resources(pcie_ep); + 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, + .write_dbi2 = qcom_pcie_dw_write_dbi2, +}; + +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"); + if (!pcie_ep->mmio_res) { + dev_err(dev, "Failed to get mmio resource\n"); + return -EINVAL; + } + + pcie_ep->mmio = devm_pci_remap_cfg_resource(dev, pcie_ep->mmio_res); + if (IS_ERR(pcie_ep->mmio)) + return PTR_ERR(pcie_ep->mmio); + + syscon = of_parse_phandle(dev->of_node, "qcom,perst-regs", 0); + if (!syscon) { + dev_dbg(dev, "PERST separation not available\n"); + return 0; + } + + 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(dev, "Failed to get io resources %d\n", ret); + return ret; + } + + pcie_ep->num_clks = devm_clk_bulk_get_all(dev, &pcie_ep->clks); + if (pcie_ep->num_clks < 0) { + dev_err(dev, "Failed to get clocks\n"); + return pcie_ep->num_clks; + } + + 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(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 ret; + + pcie_ep->global_irq = platform_get_irq_byname(pdev, "global"); + if (pcie_ep->global_irq < 0) + return pcie_ep->global_irq; + + ret = devm_request_threaded_irq(&pdev->dev, pcie_ep->global_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(pcie_ep->global_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 int qcom_pcie_ep_link_transition_count(struct seq_file *s, void *data) +{ + struct qcom_pcie_ep *pcie_ep = (struct qcom_pcie_ep *) + dev_get_drvdata(s->private); + + seq_printf(s, "L0s transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L0S)); + + seq_printf(s, "L1 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L1)); + + seq_printf(s, "L1.1 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1)); + + seq_printf(s, "L1.2 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2)); + + seq_printf(s, "L2 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L2)); + + return 0; +} + +static void qcom_pcie_ep_init_debugfs(struct qcom_pcie_ep *pcie_ep) +{ + struct dw_pcie *pci = &pcie_ep->pci; + + debugfs_create_devm_seqfile(pci->dev, "link_transition_count", pcie_ep->debugfs, + qcom_pcie_ep_link_transition_count); +} + +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 const 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; + char *name; + 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 = qcom_pcie_enable_resources(pcie_ep); + if (ret) { + dev_err(dev, "Failed to enable resources: %d\n", ret); + return ret; + } + + ret = dw_pcie_ep_init(&pcie_ep->pci.ep); + if (ret) { + dev_err(dev, "Failed to initialize endpoint: %d\n", ret); + goto err_disable_resources; + } + + ret = qcom_pcie_ep_enable_irq_resources(pdev, pcie_ep); + if (ret) + goto err_disable_resources; + + name = devm_kasprintf(dev, GFP_KERNEL, "%pOFP", dev->of_node); + if (!name) { + ret = -ENOMEM; + goto err_disable_irqs; + } + + pcie_ep->debugfs = debugfs_create_dir(name, NULL); + qcom_pcie_ep_init_debugfs(pcie_ep); + + return 0; + +err_disable_irqs: + disable_irq(pcie_ep->global_irq); + disable_irq(pcie_ep->perst_irq); + +err_disable_resources: + qcom_pcie_disable_resources(pcie_ep); + + return ret; +} + +static int qcom_pcie_ep_remove(struct platform_device *pdev) +{ + struct qcom_pcie_ep *pcie_ep = platform_get_drvdata(pdev); + + disable_irq(pcie_ep->global_irq); + disable_irq(pcie_ep->perst_irq); + + debugfs_remove_recursive(pcie_ep->debugfs); + + if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED) + return 0; + + qcom_pcie_disable_resources(pcie_ep); + + return 0; +} + +static const struct of_device_id qcom_pcie_ep_match[] = { + { .compatible = "qcom,sdx55-pcie-ep", }, + { .compatible = "qcom,sm8450-pcie-ep", }, + { } +}; +MODULE_DEVICE_TABLE(of, qcom_pcie_ep_match); + +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"); |