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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 17:39:57 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 17:39:57 +0000 |
commit | dc50eab76b709d68175a358d6e23a5a3890764d3 (patch) | |
tree | c754d0390db060af0213ff994f0ac310e4cfd6e9 /drivers/pci/controller/dwc/pcie-rcar-gen4.c | |
parent | Adding debian version 6.6.15-2. (diff) | |
download | linux-dc50eab76b709d68175a358d6e23a5a3890764d3.tar.xz linux-dc50eab76b709d68175a358d6e23a5a3890764d3.zip |
Merging upstream version 6.7.7.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-rcar-gen4.c')
-rw-r--r-- | drivers/pci/controller/dwc/pcie-rcar-gen4.c | 527 |
1 files changed, 527 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c new file mode 100644 index 0000000000..3bc45e513b --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c @@ -0,0 +1,527 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PCIe controller driver for Renesas R-Car Gen4 Series SoCs + * Copyright (C) 2022-2023 Renesas Electronics Corporation + */ + +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> + +#include "../../pci.h" +#include "pcie-designware.h" + +/* Renesas-specific */ +/* PCIe Mode Setting Register 0 */ +#define PCIEMSR0 0x0000 +#define BIFUR_MOD_SET_ON BIT(0) +#define DEVICE_TYPE_EP 0 +#define DEVICE_TYPE_RC BIT(4) + +/* PCIe Interrupt Status 0 */ +#define PCIEINTSTS0 0x0084 + +/* PCIe Interrupt Status 0 Enable */ +#define PCIEINTSTS0EN 0x0310 +#define MSI_CTRL_INT BIT(26) +#define SMLH_LINK_UP BIT(7) +#define RDLH_LINK_UP BIT(6) + +/* PCIe DMA Interrupt Status Enable */ +#define PCIEDMAINTSTSEN 0x0314 +#define PCIEDMAINTSTSEN_INIT GENMASK(15, 0) + +/* PCIe Reset Control Register 1 */ +#define PCIERSTCTRL1 0x0014 +#define APP_HOLD_PHY_RST BIT(16) +#define APP_LTSSM_ENABLE BIT(0) + +#define RCAR_NUM_SPEED_CHANGE_RETRIES 10 +#define RCAR_MAX_LINK_SPEED 4 + +#define RCAR_GEN4_PCIE_EP_FUNC_DBI_OFFSET 0x1000 +#define RCAR_GEN4_PCIE_EP_FUNC_DBI2_OFFSET 0x800 + +struct rcar_gen4_pcie { + struct dw_pcie dw; + void __iomem *base; + struct platform_device *pdev; + enum dw_pcie_device_mode mode; +}; +#define to_rcar_gen4_pcie(_dw) container_of(_dw, struct rcar_gen4_pcie, dw) + +/* Common */ +static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar, + bool enable) +{ + u32 val; + + val = readl(rcar->base + PCIERSTCTRL1); + if (enable) { + val |= APP_LTSSM_ENABLE; + val &= ~APP_HOLD_PHY_RST; + } else { + /* + * Since the datasheet of R-Car doesn't mention how to assert + * the APP_HOLD_PHY_RST, don't assert it again. Otherwise, + * hang-up issue happened in the dw_edma_core_off() when + * the controller didn't detect a PCI device. + */ + val &= ~APP_LTSSM_ENABLE; + } + writel(val, rcar->base + PCIERSTCTRL1); +} + +static int rcar_gen4_pcie_link_up(struct dw_pcie *dw) +{ + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + u32 val, mask; + + val = readl(rcar->base + PCIEINTSTS0); + mask = RDLH_LINK_UP | SMLH_LINK_UP; + + return (val & mask) == mask; +} + +/* + * Manually initiate the speed change. Return 0 if change succeeded; otherwise + * -ETIMEDOUT. + */ +static int rcar_gen4_pcie_speed_change(struct dw_pcie *dw) +{ + u32 val; + int i; + + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); + val &= ~PORT_LOGIC_SPEED_CHANGE; + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); + + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); + val |= PORT_LOGIC_SPEED_CHANGE; + dw_pcie_writel_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL, val); + + for (i = 0; i < RCAR_NUM_SPEED_CHANGE_RETRIES; i++) { + val = dw_pcie_readl_dbi(dw, PCIE_LINK_WIDTH_SPEED_CONTROL); + if (!(val & PORT_LOGIC_SPEED_CHANGE)) + return 0; + usleep_range(10000, 11000); + } + + return -ETIMEDOUT; +} + +/* + * Enable LTSSM of this controller and manually initiate the speed change. + * Always return 0. + */ +static int rcar_gen4_pcie_start_link(struct dw_pcie *dw) +{ + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + int i, changes; + + rcar_gen4_pcie_ltssm_enable(rcar, true); + + /* + * Require direct speed change with retrying here if the link_gen is + * PCIe Gen2 or higher. + */ + changes = min_not_zero(dw->link_gen, RCAR_MAX_LINK_SPEED) - 1; + + /* + * Since dw_pcie_setup_rc() sets it once, PCIe Gen2 will be trained. + * So, this needs remaining times for up to PCIe Gen4 if RC mode. + */ + if (changes && rcar->mode == DW_PCIE_RC_TYPE) + changes--; + + for (i = 0; i < changes; i++) { + /* It may not be connected in EP mode yet. So, break the loop */ + if (rcar_gen4_pcie_speed_change(dw)) + break; + } + + return 0; +} + +static void rcar_gen4_pcie_stop_link(struct dw_pcie *dw) +{ + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + + rcar_gen4_pcie_ltssm_enable(rcar, false); +} + +static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar) +{ + struct dw_pcie *dw = &rcar->dw; + u32 val; + int ret; + + ret = clk_bulk_prepare_enable(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); + if (ret) { + dev_err(dw->dev, "Enabling core clocks failed\n"); + return ret; + } + + if (!reset_control_status(dw->core_rsts[DW_PCIE_PWR_RST].rstc)) + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); + + val = readl(rcar->base + PCIEMSR0); + if (rcar->mode == DW_PCIE_RC_TYPE) { + val |= DEVICE_TYPE_RC; + } else if (rcar->mode == DW_PCIE_EP_TYPE) { + val |= DEVICE_TYPE_EP; + } else { + ret = -EINVAL; + goto err_unprepare; + } + + if (dw->num_lanes < 4) + val |= BIFUR_MOD_SET_ON; + + writel(val, rcar->base + PCIEMSR0); + + ret = reset_control_deassert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); + if (ret) + goto err_unprepare; + + return 0; + +err_unprepare: + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); + + return ret; +} + +static void rcar_gen4_pcie_common_deinit(struct rcar_gen4_pcie *rcar) +{ + struct dw_pcie *dw = &rcar->dw; + + reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks); +} + +static int rcar_gen4_pcie_prepare(struct rcar_gen4_pcie *rcar) +{ + struct device *dev = rcar->dw.dev; + int err; + + pm_runtime_enable(dev); + err = pm_runtime_resume_and_get(dev); + if (err < 0) { + dev_err(dev, "Runtime resume failed\n"); + pm_runtime_disable(dev); + } + + return err; +} + +static void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar) +{ + struct device *dev = rcar->dw.dev; + + pm_runtime_put(dev); + pm_runtime_disable(dev); +} + +static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar) +{ + /* Renesas-specific registers */ + rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app"); + + return PTR_ERR_OR_ZERO(rcar->base); +} + +static const struct dw_pcie_ops dw_pcie_ops = { + .start_link = rcar_gen4_pcie_start_link, + .stop_link = rcar_gen4_pcie_stop_link, + .link_up = rcar_gen4_pcie_link_up, +}; + +static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rcar_gen4_pcie *rcar; + + rcar = devm_kzalloc(dev, sizeof(*rcar), GFP_KERNEL); + if (!rcar) + return ERR_PTR(-ENOMEM); + + rcar->dw.ops = &dw_pcie_ops; + rcar->dw.dev = dev; + rcar->pdev = pdev; + dw_pcie_cap_set(&rcar->dw, EDMA_UNROLL); + dw_pcie_cap_set(&rcar->dw, REQ_RES); + platform_set_drvdata(pdev, rcar); + + return rcar; +} + +/* Host mode */ +static int rcar_gen4_pcie_host_init(struct dw_pcie_rp *pp) +{ + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + int ret; + u32 val; + + gpiod_set_value_cansleep(dw->pe_rst, 1); + + ret = rcar_gen4_pcie_common_init(rcar); + if (ret) + return ret; + + /* + * According to the section 3.5.7.2 "RC Mode" in DWC PCIe Dual Mode + * Rev.5.20a and 3.5.6.1 "RC mode" in DWC PCIe RC databook v5.20a, we + * should disable two BARs to avoid unnecessary memory assignment + * during device enumeration. + */ + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_0, 0x0); + dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_1, 0x0); + + /* Enable MSI interrupt signal */ + val = readl(rcar->base + PCIEINTSTS0EN); + val |= MSI_CTRL_INT; + writel(val, rcar->base + PCIEINTSTS0EN); + + msleep(PCIE_T_PVPERL_MS); /* pe_rst requires 100msec delay */ + + gpiod_set_value_cansleep(dw->pe_rst, 0); + + return 0; +} + +static void rcar_gen4_pcie_host_deinit(struct dw_pcie_rp *pp) +{ + struct dw_pcie *dw = to_dw_pcie_from_pp(pp); + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + + gpiod_set_value_cansleep(dw->pe_rst, 1); + rcar_gen4_pcie_common_deinit(rcar); +} + +static const struct dw_pcie_host_ops rcar_gen4_pcie_host_ops = { + .host_init = rcar_gen4_pcie_host_init, + .host_deinit = rcar_gen4_pcie_host_deinit, +}; + +static int rcar_gen4_add_dw_pcie_rp(struct rcar_gen4_pcie *rcar) +{ + struct dw_pcie_rp *pp = &rcar->dw.pp; + + if (!IS_ENABLED(CONFIG_PCIE_RCAR_GEN4_HOST)) + return -ENODEV; + + pp->num_vectors = MAX_MSI_IRQS; + pp->ops = &rcar_gen4_pcie_host_ops; + + return dw_pcie_host_init(pp); +} + +static void rcar_gen4_remove_dw_pcie_rp(struct rcar_gen4_pcie *rcar) +{ + dw_pcie_host_deinit(&rcar->dw.pp); +} + +/* Endpoint mode */ +static void rcar_gen4_pcie_ep_pre_init(struct dw_pcie_ep *ep) +{ + struct dw_pcie *dw = to_dw_pcie_from_ep(ep); + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + int ret; + + ret = rcar_gen4_pcie_common_init(rcar); + if (ret) + return; + + writel(PCIEDMAINTSTSEN_INIT, rcar->base + PCIEDMAINTSTSEN); +} + +static void rcar_gen4_pcie_ep_init(struct dw_pcie_ep *ep) +{ + struct dw_pcie *pci = to_dw_pcie_from_ep(ep); + enum pci_barno bar; + + for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) + dw_pcie_ep_reset_bar(pci, bar); +} + +static void rcar_gen4_pcie_ep_deinit(struct dw_pcie_ep *ep) +{ + struct dw_pcie *dw = to_dw_pcie_from_ep(ep); + struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw); + + writel(0, rcar->base + PCIEDMAINTSTSEN); + rcar_gen4_pcie_common_deinit(rcar); +} + +static int rcar_gen4_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no, + enum pci_epc_irq_type type, + u16 interrupt_num) +{ + struct dw_pcie *dw = 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(dw->dev, "Unknown IRQ type\n"); + return -EINVAL; + } + + return 0; +} + +static const struct pci_epc_features rcar_gen4_pcie_epc_features = { + .linkup_notifier = false, + .msi_capable = true, + .msix_capable = false, + .reserved_bar = 1 << BAR_1 | 1 << BAR_3 | 1 << BAR_5, + .align = SZ_1M, +}; + +static const struct pci_epc_features* +rcar_gen4_pcie_ep_get_features(struct dw_pcie_ep *ep) +{ + return &rcar_gen4_pcie_epc_features; +} + +static unsigned int rcar_gen4_pcie_ep_func_conf_select(struct dw_pcie_ep *ep, + u8 func_no) +{ + return func_no * RCAR_GEN4_PCIE_EP_FUNC_DBI_OFFSET; +} + +static unsigned int rcar_gen4_pcie_ep_get_dbi2_offset(struct dw_pcie_ep *ep, + u8 func_no) +{ + return func_no * RCAR_GEN4_PCIE_EP_FUNC_DBI2_OFFSET; +} + +static const struct dw_pcie_ep_ops pcie_ep_ops = { + .pre_init = rcar_gen4_pcie_ep_pre_init, + .ep_init = rcar_gen4_pcie_ep_init, + .deinit = rcar_gen4_pcie_ep_deinit, + .raise_irq = rcar_gen4_pcie_ep_raise_irq, + .get_features = rcar_gen4_pcie_ep_get_features, + .func_conf_select = rcar_gen4_pcie_ep_func_conf_select, + .get_dbi2_offset = rcar_gen4_pcie_ep_get_dbi2_offset, +}; + +static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar) +{ + struct dw_pcie_ep *ep = &rcar->dw.ep; + + if (!IS_ENABLED(CONFIG_PCIE_RCAR_GEN4_EP)) + return -ENODEV; + + ep->ops = &pcie_ep_ops; + + return dw_pcie_ep_init(ep); +} + +static void rcar_gen4_remove_dw_pcie_ep(struct rcar_gen4_pcie *rcar) +{ + dw_pcie_ep_exit(&rcar->dw.ep); +} + +/* Common */ +static int rcar_gen4_add_dw_pcie(struct rcar_gen4_pcie *rcar) +{ + rcar->mode = (enum dw_pcie_device_mode)of_device_get_match_data(&rcar->pdev->dev); + + switch (rcar->mode) { + case DW_PCIE_RC_TYPE: + return rcar_gen4_add_dw_pcie_rp(rcar); + case DW_PCIE_EP_TYPE: + return rcar_gen4_add_dw_pcie_ep(rcar); + default: + return -EINVAL; + } +} + +static int rcar_gen4_pcie_probe(struct platform_device *pdev) +{ + struct rcar_gen4_pcie *rcar; + int err; + + rcar = rcar_gen4_pcie_alloc(pdev); + if (IS_ERR(rcar)) + return PTR_ERR(rcar); + + err = rcar_gen4_pcie_get_resources(rcar); + if (err) + return err; + + err = rcar_gen4_pcie_prepare(rcar); + if (err) + return err; + + err = rcar_gen4_add_dw_pcie(rcar); + if (err) + goto err_unprepare; + + return 0; + +err_unprepare: + rcar_gen4_pcie_unprepare(rcar); + + return err; +} + +static void rcar_gen4_remove_dw_pcie(struct rcar_gen4_pcie *rcar) +{ + switch (rcar->mode) { + case DW_PCIE_RC_TYPE: + rcar_gen4_remove_dw_pcie_rp(rcar); + break; + case DW_PCIE_EP_TYPE: + rcar_gen4_remove_dw_pcie_ep(rcar); + break; + default: + break; + } +} + +static void rcar_gen4_pcie_remove(struct platform_device *pdev) +{ + struct rcar_gen4_pcie *rcar = platform_get_drvdata(pdev); + + rcar_gen4_remove_dw_pcie(rcar); + rcar_gen4_pcie_unprepare(rcar); +} + +static const struct of_device_id rcar_gen4_pcie_of_match[] = { + { + .compatible = "renesas,rcar-gen4-pcie", + .data = (void *)DW_PCIE_RC_TYPE, + }, + { + .compatible = "renesas,rcar-gen4-pcie-ep", + .data = (void *)DW_PCIE_EP_TYPE, + }, + {}, +}; +MODULE_DEVICE_TABLE(of, rcar_gen4_pcie_of_match); + +static struct platform_driver rcar_gen4_pcie_driver = { + .driver = { + .name = "pcie-rcar-gen4", + .of_match_table = rcar_gen4_pcie_of_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, + .probe = rcar_gen4_pcie_probe, + .remove_new = rcar_gen4_pcie_remove, +}; +module_platform_driver(rcar_gen4_pcie_driver); + +MODULE_DESCRIPTION("Renesas R-Car Gen4 PCIe controller driver"); +MODULE_LICENSE("GPL"); |