| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * PCIe host controller driver for Intel Gateway SoCs |
| * |
| * Copyright (c) 2019 Intel Corporation. |
| */ |
| |
| #include <linux/bitfield.h> |
| #include <linux/clk.h> |
| #include <linux/gpio/consumer.h> |
| #include <linux/iopoll.h> |
| #include <linux/pci_regs.h> |
| #include <linux/phy/phy.h> |
| #include <linux/platform_device.h> |
| #include <linux/reset.h> |
| |
| #include "../../pci.h" |
| #include "pcie-designware.h" |
| |
| #define PORT_AFR_N_FTS_GEN12_DFT (SZ_128 - 1) |
| #define PORT_AFR_N_FTS_GEN3 180 |
| #define PORT_AFR_N_FTS_GEN4 196 |
| |
| /* PCIe Application logic Registers */ |
| #define PCIE_APP_CCR 0x10 |
| #define PCIE_APP_CCR_LTSSM_ENABLE BIT(0) |
| |
| #define PCIE_APP_MSG_CR 0x30 |
| #define PCIE_APP_MSG_XMT_PM_TURNOFF BIT(0) |
| |
| #define PCIE_APP_PMC 0x44 |
| #define PCIE_APP_PMC_IN_L2 BIT(20) |
| |
| #define PCIE_APP_IRNEN 0xF4 |
| #define PCIE_APP_IRNCR 0xF8 |
| #define PCIE_APP_IRN_AER_REPORT BIT(0) |
| #define PCIE_APP_IRN_PME BIT(2) |
| #define PCIE_APP_IRN_RX_VDM_MSG BIT(4) |
| #define PCIE_APP_IRN_PM_TO_ACK BIT(9) |
| #define PCIE_APP_IRN_LINK_AUTO_BW_STAT BIT(11) |
| #define PCIE_APP_IRN_BW_MGT BIT(12) |
| #define PCIE_APP_IRN_INTA BIT(13) |
| #define PCIE_APP_IRN_INTB BIT(14) |
| #define PCIE_APP_IRN_INTC BIT(15) |
| #define PCIE_APP_IRN_INTD BIT(16) |
| #define PCIE_APP_IRN_MSG_LTR BIT(18) |
| #define PCIE_APP_IRN_SYS_ERR_RC BIT(29) |
| #define PCIE_APP_INTX_OFST 12 |
| |
| #define PCIE_APP_IRN_INT \ |
| (PCIE_APP_IRN_AER_REPORT | PCIE_APP_IRN_PME | \ |
| PCIE_APP_IRN_RX_VDM_MSG | PCIE_APP_IRN_SYS_ERR_RC | \ |
| PCIE_APP_IRN_PM_TO_ACK | PCIE_APP_IRN_MSG_LTR | \ |
| PCIE_APP_IRN_BW_MGT | PCIE_APP_IRN_LINK_AUTO_BW_STAT | \ |
| PCIE_APP_IRN_INTA | PCIE_APP_IRN_INTB | \ |
| PCIE_APP_IRN_INTC | PCIE_APP_IRN_INTD) |
| |
| #define BUS_IATU_OFFSET SZ_256M |
| #define RESET_INTERVAL_MS 100 |
| |
| struct intel_pcie_soc { |
| unsigned int pcie_ver; |
| }; |
| |
| struct intel_pcie_port { |
| struct dw_pcie pci; |
| void __iomem *app_base; |
| struct gpio_desc *reset_gpio; |
| u32 rst_intrvl; |
| struct clk *core_clk; |
| struct reset_control *core_rst; |
| struct phy *phy; |
| }; |
| |
| static void pcie_update_bits(void __iomem *base, u32 ofs, u32 mask, u32 val) |
| { |
| u32 old; |
| |
| old = readl(base + ofs); |
| val = (old & ~mask) | (val & mask); |
| |
| if (val != old) |
| writel(val, base + ofs); |
| } |
| |
| static inline void pcie_app_wr(struct intel_pcie_port *lpp, u32 ofs, u32 val) |
| { |
| writel(val, lpp->app_base + ofs); |
| } |
| |
| static void pcie_app_wr_mask(struct intel_pcie_port *lpp, u32 ofs, |
| u32 mask, u32 val) |
| { |
| pcie_update_bits(lpp->app_base, ofs, mask, val); |
| } |
| |
| static inline u32 pcie_rc_cfg_rd(struct intel_pcie_port *lpp, u32 ofs) |
| { |
| return dw_pcie_readl_dbi(&lpp->pci, ofs); |
| } |
| |
| static inline void pcie_rc_cfg_wr(struct intel_pcie_port *lpp, u32 ofs, u32 val) |
| { |
| dw_pcie_writel_dbi(&lpp->pci, ofs, val); |
| } |
| |
| static void pcie_rc_cfg_wr_mask(struct intel_pcie_port *lpp, u32 ofs, |
| u32 mask, u32 val) |
| { |
| pcie_update_bits(lpp->pci.dbi_base, ofs, mask, val); |
| } |
| |
| static void intel_pcie_ltssm_enable(struct intel_pcie_port *lpp) |
| { |
| pcie_app_wr_mask(lpp, PCIE_APP_CCR, PCIE_APP_CCR_LTSSM_ENABLE, |
| PCIE_APP_CCR_LTSSM_ENABLE); |
| } |
| |
| static void intel_pcie_ltssm_disable(struct intel_pcie_port *lpp) |
| { |
| pcie_app_wr_mask(lpp, PCIE_APP_CCR, PCIE_APP_CCR_LTSSM_ENABLE, 0); |
| } |
| |
| static void intel_pcie_link_setup(struct intel_pcie_port *lpp) |
| { |
| u32 val; |
| u8 offset = dw_pcie_find_capability(&lpp->pci, PCI_CAP_ID_EXP); |
| |
| val = pcie_rc_cfg_rd(lpp, offset + PCI_EXP_LNKCTL); |
| |
| val &= ~(PCI_EXP_LNKCTL_LD | PCI_EXP_LNKCTL_ASPMC); |
| pcie_rc_cfg_wr(lpp, offset + PCI_EXP_LNKCTL, val); |
| } |
| |
| static void intel_pcie_init_n_fts(struct dw_pcie *pci) |
| { |
| switch (pci->link_gen) { |
| case 3: |
| pci->n_fts[1] = PORT_AFR_N_FTS_GEN3; |
| break; |
| case 4: |
| pci->n_fts[1] = PORT_AFR_N_FTS_GEN4; |
| break; |
| default: |
| pci->n_fts[1] = PORT_AFR_N_FTS_GEN12_DFT; |
| break; |
| } |
| pci->n_fts[0] = PORT_AFR_N_FTS_GEN12_DFT; |
| } |
| |
| static int intel_pcie_ep_rst_init(struct intel_pcie_port *lpp) |
| { |
| struct device *dev = lpp->pci.dev; |
| int ret; |
| |
| lpp->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); |
| if (IS_ERR(lpp->reset_gpio)) { |
| ret = PTR_ERR(lpp->reset_gpio); |
| if (ret != -EPROBE_DEFER) |
| dev_err(dev, "Failed to request PCIe GPIO: %d\n", ret); |
| return ret; |
| } |
| |
| /* Make initial reset last for 100us */ |
| usleep_range(100, 200); |
| |
| return 0; |
| } |
| |
| static void intel_pcie_core_rst_assert(struct intel_pcie_port *lpp) |
| { |
| reset_control_assert(lpp->core_rst); |
| } |
| |
| static void intel_pcie_core_rst_deassert(struct intel_pcie_port *lpp) |
| { |
| /* |
| * One micro-second delay to make sure the reset pulse |
| * wide enough so that core reset is clean. |
| */ |
| udelay(1); |
| reset_control_deassert(lpp->core_rst); |
| |
| /* |
| * Some SoC core reset also reset PHY, more delay needed |
| * to make sure the reset process is done. |
| */ |
| usleep_range(1000, 2000); |
| } |
| |
| static void intel_pcie_device_rst_assert(struct intel_pcie_port *lpp) |
| { |
| gpiod_set_value_cansleep(lpp->reset_gpio, 1); |
| } |
| |
| static void intel_pcie_device_rst_deassert(struct intel_pcie_port *lpp) |
| { |
| msleep(lpp->rst_intrvl); |
| gpiod_set_value_cansleep(lpp->reset_gpio, 0); |
| } |
| |
| static void intel_pcie_core_irq_disable(struct intel_pcie_port *lpp) |
| { |
| pcie_app_wr(lpp, PCIE_APP_IRNEN, 0); |
| pcie_app_wr(lpp, PCIE_APP_IRNCR, PCIE_APP_IRN_INT); |
| } |
| |
| static int intel_pcie_get_resources(struct platform_device *pdev) |
| { |
| struct intel_pcie_port *lpp = platform_get_drvdata(pdev); |
| struct dw_pcie *pci = &lpp->pci; |
| struct device *dev = pci->dev; |
| int ret; |
| |
| lpp->core_clk = devm_clk_get(dev, NULL); |
| if (IS_ERR(lpp->core_clk)) { |
| ret = PTR_ERR(lpp->core_clk); |
| if (ret != -EPROBE_DEFER) |
| dev_err(dev, "Failed to get clks: %d\n", ret); |
| return ret; |
| } |
| |
| lpp->core_rst = devm_reset_control_get(dev, NULL); |
| if (IS_ERR(lpp->core_rst)) { |
| ret = PTR_ERR(lpp->core_rst); |
| if (ret != -EPROBE_DEFER) |
| dev_err(dev, "Failed to get resets: %d\n", ret); |
| return ret; |
| } |
| |
| ret = device_property_read_u32(dev, "reset-assert-ms", |
| &lpp->rst_intrvl); |
| if (ret) |
| lpp->rst_intrvl = RESET_INTERVAL_MS; |
| |
| lpp->app_base = devm_platform_ioremap_resource_byname(pdev, "app"); |
| if (IS_ERR(lpp->app_base)) |
| return PTR_ERR(lpp->app_base); |
| |
| lpp->phy = devm_phy_get(dev, "pcie"); |
| if (IS_ERR(lpp->phy)) { |
| ret = PTR_ERR(lpp->phy); |
| if (ret != -EPROBE_DEFER) |
| dev_err(dev, "Couldn't get pcie-phy: %d\n", ret); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int intel_pcie_wait_l2(struct intel_pcie_port *lpp) |
| { |
| u32 value; |
| int ret; |
| struct dw_pcie *pci = &lpp->pci; |
| |
| if (pci->link_gen < 3) |
| return 0; |
| |
| /* Send PME_TURN_OFF message */ |
| pcie_app_wr_mask(lpp, PCIE_APP_MSG_CR, PCIE_APP_MSG_XMT_PM_TURNOFF, |
| PCIE_APP_MSG_XMT_PM_TURNOFF); |
| |
| /* Read PMC status and wait for falling into L2 link state */ |
| ret = readl_poll_timeout(lpp->app_base + PCIE_APP_PMC, value, |
| value & PCIE_APP_PMC_IN_L2, 20, |
| jiffies_to_usecs(5 * HZ)); |
| if (ret) |
| dev_err(lpp->pci.dev, "PCIe link enter L2 timeout!\n"); |
| |
| return ret; |
| } |
| |
| static void intel_pcie_turn_off(struct intel_pcie_port *lpp) |
| { |
| if (dw_pcie_link_up(&lpp->pci)) |
| intel_pcie_wait_l2(lpp); |
| |
| /* Put endpoint device in reset state */ |
| intel_pcie_device_rst_assert(lpp); |
| pcie_rc_cfg_wr_mask(lpp, PCI_COMMAND, PCI_COMMAND_MEMORY, 0); |
| } |
| |
| static int intel_pcie_host_setup(struct intel_pcie_port *lpp) |
| { |
| int ret; |
| struct dw_pcie *pci = &lpp->pci; |
| |
| intel_pcie_core_rst_assert(lpp); |
| intel_pcie_device_rst_assert(lpp); |
| |
| ret = phy_init(lpp->phy); |
| if (ret) |
| return ret; |
| |
| intel_pcie_core_rst_deassert(lpp); |
| |
| ret = clk_prepare_enable(lpp->core_clk); |
| if (ret) { |
| dev_err(lpp->pci.dev, "Core clock enable failed: %d\n", ret); |
| goto clk_err; |
| } |
| |
| pci->atu_base = pci->dbi_base + 0xC0000; |
| |
| intel_pcie_ltssm_disable(lpp); |
| intel_pcie_link_setup(lpp); |
| intel_pcie_init_n_fts(pci); |
| dw_pcie_setup_rc(&pci->pp); |
| dw_pcie_upconfig_setup(pci); |
| |
| intel_pcie_device_rst_deassert(lpp); |
| intel_pcie_ltssm_enable(lpp); |
| |
| ret = dw_pcie_wait_for_link(pci); |
| if (ret) |
| goto app_init_err; |
| |
| /* Enable integrated interrupts */ |
| pcie_app_wr_mask(lpp, PCIE_APP_IRNEN, PCIE_APP_IRN_INT, |
| PCIE_APP_IRN_INT); |
| |
| return 0; |
| |
| app_init_err: |
| clk_disable_unprepare(lpp->core_clk); |
| clk_err: |
| intel_pcie_core_rst_assert(lpp); |
| phy_exit(lpp->phy); |
| |
| return ret; |
| } |
| |
| static void __intel_pcie_remove(struct intel_pcie_port *lpp) |
| { |
| intel_pcie_core_irq_disable(lpp); |
| intel_pcie_turn_off(lpp); |
| clk_disable_unprepare(lpp->core_clk); |
| intel_pcie_core_rst_assert(lpp); |
| phy_exit(lpp->phy); |
| } |
| |
| static int intel_pcie_remove(struct platform_device *pdev) |
| { |
| struct intel_pcie_port *lpp = platform_get_drvdata(pdev); |
| struct pcie_port *pp = &lpp->pci.pp; |
| |
| dw_pcie_host_deinit(pp); |
| __intel_pcie_remove(lpp); |
| |
| return 0; |
| } |
| |
| static int __maybe_unused intel_pcie_suspend_noirq(struct device *dev) |
| { |
| struct intel_pcie_port *lpp = dev_get_drvdata(dev); |
| int ret; |
| |
| intel_pcie_core_irq_disable(lpp); |
| ret = intel_pcie_wait_l2(lpp); |
| if (ret) |
| return ret; |
| |
| phy_exit(lpp->phy); |
| clk_disable_unprepare(lpp->core_clk); |
| return ret; |
| } |
| |
| static int __maybe_unused intel_pcie_resume_noirq(struct device *dev) |
| { |
| struct intel_pcie_port *lpp = dev_get_drvdata(dev); |
| |
| return intel_pcie_host_setup(lpp); |
| } |
| |
| static int intel_pcie_rc_init(struct pcie_port *pp) |
| { |
| struct dw_pcie *pci = to_dw_pcie_from_pp(pp); |
| struct intel_pcie_port *lpp = dev_get_drvdata(pci->dev); |
| |
| return intel_pcie_host_setup(lpp); |
| } |
| |
| static u64 intel_pcie_cpu_addr(struct dw_pcie *pcie, u64 cpu_addr) |
| { |
| return cpu_addr + BUS_IATU_OFFSET; |
| } |
| |
| static const struct dw_pcie_ops intel_pcie_ops = { |
| .cpu_addr_fixup = intel_pcie_cpu_addr, |
| }; |
| |
| static const struct dw_pcie_host_ops intel_pcie_dw_ops = { |
| .host_init = intel_pcie_rc_init, |
| }; |
| |
| static const struct intel_pcie_soc pcie_data = { |
| .pcie_ver = 0x520A, |
| }; |
| |
| static int intel_pcie_probe(struct platform_device *pdev) |
| { |
| const struct intel_pcie_soc *data; |
| struct device *dev = &pdev->dev; |
| struct intel_pcie_port *lpp; |
| struct pcie_port *pp; |
| struct dw_pcie *pci; |
| int ret; |
| |
| lpp = devm_kzalloc(dev, sizeof(*lpp), GFP_KERNEL); |
| if (!lpp) |
| return -ENOMEM; |
| |
| platform_set_drvdata(pdev, lpp); |
| pci = &lpp->pci; |
| pci->dev = dev; |
| pp = &pci->pp; |
| |
| ret = intel_pcie_get_resources(pdev); |
| if (ret) |
| return ret; |
| |
| ret = intel_pcie_ep_rst_init(lpp); |
| if (ret) |
| return ret; |
| |
| data = device_get_match_data(dev); |
| if (!data) |
| return -ENODEV; |
| |
| pci->ops = &intel_pcie_ops; |
| pci->version = data->pcie_ver; |
| pp->ops = &intel_pcie_dw_ops; |
| |
| ret = dw_pcie_host_init(pp); |
| if (ret) { |
| dev_err(dev, "Cannot initialize host\n"); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static const struct dev_pm_ops intel_pcie_pm_ops = { |
| SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(intel_pcie_suspend_noirq, |
| intel_pcie_resume_noirq) |
| }; |
| |
| static const struct of_device_id of_intel_pcie_match[] = { |
| { .compatible = "intel,lgm-pcie", .data = &pcie_data }, |
| {} |
| }; |
| |
| static struct platform_driver intel_pcie_driver = { |
| .probe = intel_pcie_probe, |
| .remove = intel_pcie_remove, |
| .driver = { |
| .name = "intel-gw-pcie", |
| .of_match_table = of_intel_pcie_match, |
| .pm = &intel_pcie_pm_ops, |
| }, |
| }; |
| builtin_platform_driver(intel_pcie_driver); |