diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c index d8eb52857f69..62b222c20464 100644 --- a/drivers/pci/controller/dwc/pcie-qcom.c +++ b/drivers/pci/controller/dwc/pcie-qcom.c @@ -56,6 +56,10 @@ #define PARF_AXI_MSTR_WR_ADDR_HALT_V2 0x1a8 #define PARF_Q2A_FLUSH 0x1ac #define PARF_LTSSM 0x1b0 +#define PARF_INT_ALL_STATUS 0x224 +#define PARF_INT_ALL_CLEAR 0x228 +#define PARF_INT_ALL_MASK 0x22c +#define PARF_STATUS 0x230 #define PARF_SID_OFFSET 0x234 #define PARF_BDF_TRANSLATE_CFG 0x24c #define PARF_DBI_BASE_ADDR_V2 0x350 @@ -133,6 +137,13 @@ /* PARF_LTSSM register fields */ #define LTSSM_EN BIT(8) #define PARF_LTSSM_STATE_MASK GENMASK(5, 0) +#define SW_CLEAR_FLUSH_MODE BIT(10) +#define FLUSH_MODE BIT(11) + +/* PARF_INT_ALL_{STATUS/CLEAR/MASK} register fields */ +#define INT_ALL_LINK_DOWN 1 +#define PARF_INT_ALL_LINK_DOWN BIT(INT_ALL_LINK_DOWN) +#define PARF_INT_MSI_DEV_0_7 GENMASK(30, 23) /* PARF_NO_SNOOP_OVERRIDE register fields */ #define WR_NO_SNOOP_OVERRIDE_EN BIT(1) @@ -144,6 +155,9 @@ /* PARF_BDF_TO_SID_CFG fields */ #define BDF_TO_SID_BYPASS BIT(0) +/* PARF_STATUS fields */ +#define FLUSH_COMPLETED BIT(8) + /* ELBI_SYS_CTRL register fields */ #define ELBI_SYS_CTRL_LT_ENABLE BIT(0) #define ELBI_SYS_CTRL_PME_TURNOFF_MSG BIT(4) @@ -172,6 +186,7 @@ PCIE_CAP_SLOT_POWER_LIMIT_SCALE) #define PERST_DELAY_US 1000 +#define FLUSH_TIMEOUT_US 100 #define QCOM_PCIE_CRC8_POLYNOMIAL (BIT(2) | BIT(1) | BIT(0)) @@ -291,10 +306,13 @@ struct qcom_pcie { struct dentry *debugfs; struct list_head ports; struct gpio_desc *reset; + int global_irq; bool use_pm_opp; }; #define to_qcom_pcie(x) dev_get_drvdata((x)->dev) +static int qcom_pcie_reset_root_port(struct pci_host_bridge *bridge, + struct pci_dev *pdev); static void __qcom_pcie_perst_assert(struct qcom_pcie *pcie, bool assert) { @@ -1406,6 +1424,8 @@ static int qcom_pcie_host_init(struct dw_pcie_rp *pp) goto err_assert_reset; } + pp->bridge->reset_root_port = qcom_pcie_reset_root_port; + return 0; err_assert_reset: @@ -1734,6 +1754,75 @@ static int qcom_pcie_set_max_opp(struct device *dev) return ret; } +/* + * Qcom PCIe controllers only support one Root Port per controller instance. So + * this function ignores the 'pci_dev' associated with the Root Port and just + * resets the host bridge, which in turn resets the Root Port also. + */ +static int qcom_pcie_reset_root_port(struct pci_host_bridge *bridge, + struct pci_dev *pdev) +{ + struct device *dev = bridge->dev.parent; + struct qcom_pcie *pcie = dev_get_drvdata(dev); + struct dw_pcie *pci = pcie->pci; + struct dw_pcie_rp *pp = &pci->pp; + u32 val; + int ret; + + /* Wait for the pending transactions to be completed */ + ret = readl_relaxed_poll_timeout(pcie->parf + PARF_STATUS, val, + val & FLUSH_COMPLETED, 10, + FLUSH_TIMEOUT_US); + if (ret) { + dev_err(dev, "Flush completion failed: %d\n", ret); + return ret; + } + + /* Clear the FLUSH_MODE to allow the core to be reset */ + val = readl(pcie->parf + PARF_LTSSM); + val |= SW_CLEAR_FLUSH_MODE; + writel(val, pcie->parf + PARF_LTSSM); + + /* Wait for the FLUSH_MODE to clear */ + ret = readl_relaxed_poll_timeout(pcie->parf + PARF_LTSSM, val, + !(val & FLUSH_MODE), 10, + FLUSH_TIMEOUT_US); + if (ret) { + dev_err(dev, "Flush mode clear failed: %d\n", ret); + return ret; + } + + qcom_pcie_host_deinit(pp); + + ret = qcom_pcie_host_init(pp); + if (ret) { + dev_err(dev, "Host init failed\n"); + return ret; + } + + ret = dw_pcie_setup_rc(pp); + if (ret) + return ret; + + /* + * Re-enable global IRQ events as the PARF_INT_ALL_MASK register is + * non-sticky. + */ + if (pcie->global_irq) + writel_relaxed(PARF_INT_ALL_LINK_DOWN | PARF_INT_MSI_DEV_0_7, + pcie->parf + PARF_INT_ALL_MASK); + + qcom_pcie_start_link(pci); + + ret = dw_pcie_wait_for_link(pci); + if (ret) + return ret; + + dev_dbg(dev, "Root Port reset completed\n"); + + return 0; +} + static int qcom_pcie_link_transition_count(struct seq_file *s, void *data) { struct qcom_pcie *pcie = (struct qcom_pcie *)dev_get_drvdata(s->private); @@ -1771,6 +1860,27 @@ static void qcom_pcie_init_debugfs(struct qcom_pcie *pcie) qcom_pcie_link_transition_count); } +static irqreturn_t qcom_pcie_global_irq_thread(int irq, void *data) +{ + struct qcom_pcie *pcie = data; + struct dw_pcie_rp *pp = &pcie->pci->pp; + struct device *dev = pcie->pci->dev; + struct pci_dev *port; + unsigned long status = readl_relaxed(pcie->parf + PARF_INT_ALL_STATUS); + + writel_relaxed(status, pcie->parf + PARF_INT_ALL_CLEAR); + + if (test_and_clear_bit(INT_ALL_LINK_DOWN, &status)) { + dev_dbg(dev, "Received Link down event\n"); + for_each_pci_bridge(port, pp->bridge->bus) { + if (pci_pcie_type(port) == PCI_EXP_TYPE_ROOT_PORT) + pci_host_handle_link_down(port); + } + } + + return IRQ_HANDLED; +} + static void qcom_pci_free_msi(void *ptr) { struct dw_pcie_rp *pp = (struct dw_pcie_rp *)ptr; @@ -1990,7 +2100,7 @@ static int qcom_pcie_probe(struct platform_device *pdev) struct dw_pcie_rp *pp; struct resource *res; struct dw_pcie *pci; - int ret; + int ret, irq; pcie_cfg = of_device_get_match_data(dev); if (!pcie_cfg) { @@ -2135,6 +2245,32 @@ static int qcom_pcie_probe(struct platform_device *pdev) goto err_phy_exit; } + irq = platform_get_irq_byname_optional(pdev, "global"); + if (irq > 0) { + const char *name; + + name = devm_kasprintf(dev, GFP_KERNEL, "qcom_pcie_global_irq%d", + pci_domain_nr(pp->bridge->bus)); + if (!name) { + ret = -ENOMEM; + goto err_host_deinit; + } + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + qcom_pcie_global_irq_thread, + IRQF_ONESHOT, name, pcie); + if (ret) { + dev_err_probe(&pdev->dev, ret, + "Failed to request Global IRQ\n"); + goto err_host_deinit; + } + + writel_relaxed(PARF_INT_ALL_LINK_DOWN | PARF_INT_MSI_DEV_0_7, + pcie->parf + PARF_INT_ALL_MASK); + + pcie->global_irq = irq; + } + qcom_pcie_icc_opp_update(pcie); if (pcie->mhi) @@ -2142,6 +2278,8 @@ static int qcom_pcie_probe(struct platform_device *pdev) return 0; +err_host_deinit: + dw_pcie_host_deinit(pp); err_phy_exit: list_for_each_entry_safe(port, tmp_port, &pcie->ports, list) { list_for_each_entry_safe(perst, tmp_perst, &port->perst, list)