linuxdebug/drivers/pci/controller/dwc/pcie-qcom-ep.c

820 lines
23 KiB
C

// 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
/* 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 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,
};
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");