Add a driver for the DesignWare-based PCIe controller found on RK356X. The existing pcie-rockchip-host driver is only used for the Rockchip-designed IP found on RK3399. Signed-off-by: Simon Xue <xxm@xxxxxxxxxxxxxx> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> --- drivers/pci/controller/dwc/Kconfig | 10 + drivers/pci/controller/dwc/Makefile | 1 + drivers/pci/controller/dwc/pcie-dw-rockchip.c | 291 ++++++++++++++++++ 3 files changed, 302 insertions(+) create mode 100644 drivers/pci/controller/dwc/pcie-dw-rockchip.c diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig index 22c5529e9a65..159791775cc6 100644 --- a/drivers/pci/controller/dwc/Kconfig +++ b/drivers/pci/controller/dwc/Kconfig @@ -214,6 +214,16 @@ config PCIE_ARTPEC6_EP Enables support for the PCIe controller in the ARTPEC-6 SoC to work in endpoint mode. This uses the DesignWare core. +config PCIE_ROCKCHIP_DW_HOST + bool "Rockchip DesignWare PCIe controller" + select PCIE_DW + select PCIE_DW_HOST + depends on ARCH_ROCKCHIP || COMPILE_TEST + depends on OF + help + Enables support for the DesignWare PCIe controller in the + Rockchip SoC except RK3399. + config PCIE_INTEL_GW bool "Intel Gateway PCIe host controller support" depends on OF && (X86 || COMPILE_TEST) diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile index a751553fa0db..30eef8e9ee8a 100644 --- a/drivers/pci/controller/dwc/Makefile +++ b/drivers/pci/controller/dwc/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_PCI_LAYERSCAPE_EP) += pci-layerscape-ep.o obj-$(CONFIG_PCIE_QCOM) += pcie-qcom.o obj-$(CONFIG_PCIE_ARMADA_8K) += pcie-armada8k.o obj-$(CONFIG_PCIE_ARTPEC6) += pcie-artpec6.o +obj-$(CONFIG_PCIE_ROCKCHIP_DW_HOST) += pcie-dw-rockchip.o obj-$(CONFIG_PCIE_INTEL_GW) += pcie-intel-gw.o obj-$(CONFIG_PCIE_KIRIN) += pcie-kirin.o obj-$(CONFIG_PCIE_HISI_STB) += pcie-histb.o diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c new file mode 100644 index 000000000000..6d003353d030 --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c @@ -0,0 +1,291 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe host controller driver for Rockchip SoCs. + * + * Copyright (C) 2021 Rockchip Electronics Co., Ltd. + * http://www.rock-chips.com + * + * Author: Simon Xue <xxm@xxxxxxxxxxxxxx> + */ + +#include <linux/clk.h> +#include <linux/gpio/consumer.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/phy/phy.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/reset.h> + +#include "pcie-designware.h" + +/* + * The upper 16 bits of PCIE_CLIENT_CONFIG are a write + * mask for the lower 16 bits. + */ +#define HIWORD_UPDATE(mask, val) (((mask) << 16) | (val)) +#define HIWORD_UPDATE_BIT(val) HIWORD_UPDATE(val, val) + +#define to_rockchip_pcie(x) dev_get_drvdata((x)->dev) + +#define PCIE_CLIENT_RC_MODE HIWORD_UPDATE_BIT(0x40) +#define PCIE_CLIENT_ENABLE_LTSSM HIWORD_UPDATE_BIT(0xc) +#define PCIE_SMLH_LINKUP BIT(16) +#define PCIE_RDLH_LINKUP BIT(17) +#define PCIE_LINKUP (PCIE_SMLH_LINKUP | PCIE_RDLH_LINKUP) +#define PCIE_L0S_ENTRY 0x11 +#define PCIE_CLIENT_GENERAL_CONTROL 0x0 +#define PCIE_CLIENT_GENERAL_DEBUG 0x104 +#define PCIE_CLIENT_HOT_RESET_CTRL 0x180 +#define PCIE_CLIENT_LTSSM_STATUS 0x300 +#define PCIE_LTSSM_ENABLE_ENHANCE BIT(4) + +struct rockchip_pcie { + struct dw_pcie pci; + void __iomem *apb_base; + struct phy *phy; + struct clk_bulk_data *clks; + unsigned int clk_cnt; + struct reset_control *rst; + struct gpio_desc *rst_gpio; + struct regulator *vpcie3v3; +}; + +static int rockchip_pcie_readl_apb(struct rockchip_pcie *rockchip, + u32 reg) +{ + return readl(rockchip->apb_base + reg); +} + +static void rockchip_pcie_writel_apb(struct rockchip_pcie *rockchip, + u32 val, u32 reg) +{ + writel(val, rockchip->apb_base + reg); +} + +static void rockchip_pcie_enable_ltssm(struct rockchip_pcie *rockchip) +{ + rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_ENABLE_LTSSM, + PCIE_CLIENT_GENERAL_CONTROL); +} + +static int rockchip_pcie_link_up(struct dw_pcie *pci) +{ + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci); + u32 val = rockchip_pcie_readl_apb(rockchip, PCIE_CLIENT_LTSSM_STATUS); + + if ((val & (PCIE_RDLH_LINKUP | PCIE_SMLH_LINKUP)) == PCIE_LINKUP && + (val & GENMASK(5, 0)) == PCIE_L0S_ENTRY) + return 1; + + return 0; +} + +static int rockchip_pcie_start_link(struct dw_pcie *pci) +{ + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci); + + /* Reset device */ + gpiod_set_value_cansleep(rockchip->rst_gpio, 0); + + rockchip_pcie_enable_ltssm(rockchip); + + /* + * PCIe requires the refclk to be stable for 100µs prior to releasing + * PERST. See table 2-4 in section 2.6.2 AC Specifications of the PCI + * Express Card Electromechanical Specification, 1.1. However, we don't + * know if the refclk is coming from RC's PHY or external OSC. If it's + * from RC, so enabling LTSSM is the just right place to release #PERST. + * We need a little more extra time as before, rather than setting just + * 100us as we don't know how long should the device need to reset. + */ + msleep(100); + gpiod_set_value_cansleep(rockchip->rst_gpio, 1); + + return 0; +} + +static void rockchip_pcie_fast_link_setup(struct rockchip_pcie *rockchip) +{ + u32 val; + + /* LTSSM enable control mode */ + val = rockchip_pcie_readl_apb(rockchip, PCIE_CLIENT_HOT_RESET_CTRL); + val |= PCIE_LTSSM_ENABLE_ENHANCE | (PCIE_LTSSM_ENABLE_ENHANCE << 16); + rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_HOT_RESET_CTRL); +} + +static int rockchip_pcie_host_init(struct pcie_port *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci); + + rockchip_pcie_fast_link_setup(rockchip); + + rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_RC_MODE, + PCIE_CLIENT_GENERAL_CONTROL); + + return 0; +} + +static const struct dw_pcie_host_ops rockchip_pcie_host_ops = { + .host_init = rockchip_pcie_host_init, +}; + +static int rockchip_pcie_clk_init(struct rockchip_pcie *rockchip) +{ + struct device *dev = rockchip->pci.dev; + int ret; + + ret = devm_clk_bulk_get_all(dev, &rockchip->clks); + if (ret < 0) + return ret; + + rockchip->clk_cnt = ret; + + return clk_bulk_prepare_enable(rockchip->clk_cnt, rockchip->clks); +} + +static int rockchip_pcie_resource_get(struct platform_device *pdev, + struct rockchip_pcie *rockchip) +{ + rockchip->apb_base = devm_platform_ioremap_resource_byname(pdev, "apb"); + if (IS_ERR(rockchip->apb_base)) + return PTR_ERR(rockchip->apb_base); + + rockchip->rst_gpio = devm_gpiod_get_optional(&pdev->dev, "reset", + GPIOD_OUT_HIGH); + if (IS_ERR(rockchip->rst_gpio)) + return PTR_ERR(rockchip->rst_gpio); + + return 0; +} + +static int rockchip_pcie_phy_init(struct rockchip_pcie *rockchip) +{ + struct device *dev = rockchip->pci.dev; + int ret; + + rockchip->phy = devm_phy_get(dev, "pcie-phy"); + if (IS_ERR(rockchip->phy)) + return dev_err_probe(dev, PTR_ERR(rockchip->phy), + "missing PHY\n"); + + ret = phy_init(rockchip->phy); + if (ret < 0) + return ret; + + ret = phy_power_on(rockchip->phy); + if (ret) + phy_exit(rockchip->phy); + + return ret; +} + +static void rockchip_pcie_phy_deinit(struct rockchip_pcie *rockchip) +{ + phy_exit(rockchip->phy); + phy_power_off(rockchip->phy); +} + +static int rockchip_pcie_reset_control_release(struct rockchip_pcie *rockchip) +{ + struct device *dev = rockchip->pci.dev; + + rockchip->rst = devm_reset_control_array_get_exclusive(dev); + if (IS_ERR(rockchip->rst)) + return dev_err_probe(dev, PTR_ERR(rockchip->rst), + "failed to get reset lines\n"); + + return reset_control_deassert(rockchip->rst); +} + +static const struct dw_pcie_ops dw_pcie_ops = { + .link_up = rockchip_pcie_link_up, + .start_link = rockchip_pcie_start_link, +}; + +static int rockchip_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rockchip_pcie *rockchip; + struct pcie_port *pp; + int ret; + + rockchip = devm_kzalloc(dev, sizeof(*rockchip), GFP_KERNEL); + if (!rockchip) + return -ENOMEM; + + platform_set_drvdata(pdev, rockchip); + + rockchip->pci.dev = dev; + rockchip->pci.ops = &dw_pcie_ops; + + pp = &rockchip->pci.pp; + pp->ops = &rockchip_pcie_host_ops; + + ret = rockchip_pcie_resource_get(pdev, rockchip); + if (ret) + return ret; + + /* DON'T MOVE ME: must be enable before PHY init */ + rockchip->vpcie3v3 = devm_regulator_get_optional(dev, "vpcie3v3"); + if (IS_ERR(rockchip->vpcie3v3)) { + if (PTR_ERR(rockchip->vpcie3v3) != -ENODEV) + return dev_err_probe(dev, PTR_ERR(rockchip->rst), + "failed to get vpcie3v3 regulator\n"); + rockchip->vpcie3v3 = NULL; + } + + if (rockchip->vpcie3v3) { + ret = regulator_enable(rockchip->vpcie3v3); + if (ret) { + dev_err(dev, "failed to enable vpcie3v3 regulator\n"); + return ret; + } + } + + ret = rockchip_pcie_phy_init(rockchip); + if (ret) + goto disable_regulator; + + ret = rockchip_pcie_reset_control_release(rockchip); + if (ret) + goto deinit_phy; + + ret = rockchip_pcie_clk_init(rockchip); + if (ret) + goto deinit_phy; + + ret = dw_pcie_host_init(pp); + if (ret) + goto deinit_clk; + + return 0; + +deinit_clk: + clk_bulk_disable_unprepare(rockchip->clk_cnt, rockchip->clks); +deinit_phy: + rockchip_pcie_phy_deinit(rockchip); +disable_regulator: + if (rockchip->vpcie3v3) + regulator_disable(rockchip->vpcie3v3); + + return ret; +} + +static const struct of_device_id rockchip_pcie_of_match[] = { + { .compatible = "rockchip,rk3568-pcie", }, + {}, +}; + +static struct platform_driver rockchip_pcie_driver = { + .driver = { + .name = "rockchip-dw-pcie", + .of_match_table = rockchip_pcie_of_match, + .suppress_bind_attrs = true, + }, + .probe = rockchip_pcie_probe, +}; +builtin_platform_driver(rockchip_pcie_driver); -- 2.25.1
