From: Hongtao Wu <billows.wu@xxxxxxxxxx> This series adds PCIe controller driver for Unisoc SoCs. This controller is based on DesignWare PCIe IP. Signed-off-by: Hongtao Wu <billows.wu@xxxxxxxxxx> Signed-off-by: Chunyan Zhang <zhang.lyra@xxxxxxxxx> --- drivers/pci/controller/dwc/Kconfig | 12 + drivers/pci/controller/dwc/Makefile | 1 + drivers/pci/controller/dwc/pcie-sprd.c | 292 +++++++++++++++++++++++++ 3 files changed, 305 insertions(+) create mode 100644 drivers/pci/controller/dwc/pcie-sprd.c diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig index 22c5529e9a65..61f0b79f963d 100644 --- a/drivers/pci/controller/dwc/Kconfig +++ b/drivers/pci/controller/dwc/Kconfig @@ -318,4 +318,16 @@ config PCIE_AL required only for DT-based platforms. ACPI platforms with the Annapurna Labs PCIe controller don't need to enable this. +config PCIE_SPRD + tristate "Unisoc PCIe controller - Host Mode" + depends on ARCH_SPRD || COMPILE_TEST + depends on PCI_MSI_IRQ_DOMAIN + select PCIE_DW_HOST + help + Unisoc PCIe controller uses the DesignWare core. It can be configured + as an Endpoint (EP) or a Root complex (RC). In order to enable host + mode (the controller works as RC), PCIE_SPRD must be selected. + Say Y or M here if you want to PCIe RC controller support on Unisoc + SoCs. + endmenu diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile index a751553fa0db..eb546e97c14a 100644 --- a/drivers/pci/controller/dwc/Makefile +++ b/drivers/pci/controller/dwc/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_PCI_MESON) += pci-meson.o obj-$(CONFIG_PCIE_TEGRA194) += pcie-tegra194.o obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o +obj-$(CONFIG_PCIE_SPRD) += pcie-sprd.o # The following drivers are for devices that use the generic ACPI # pci_root.c driver but don't support standard ECAM config access. diff --git a/drivers/pci/controller/dwc/pcie-sprd.c b/drivers/pci/controller/dwc/pcie-sprd.c new file mode 100644 index 000000000000..2ccb99eda24f --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-sprd.c @@ -0,0 +1,292 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe host controller driver for Unisoc SoCs + * + * Copyright (C) 2020-2021 Unisoc, Inc. + * + * Author: Hongtao Wu <Billows.Wu@xxxxxxxxxx> + */ + +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/interrupt.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/regmap.h> + +#include "pcie-designware.h" + +/* aon apb syscon */ +#define IPA_ACCESS_CFG 0xcd8 +#define AON_ACCESS_PCIE_EN BIT(1) + +/* pmu apb syscon */ +#define SNPS_PCIE3_SLP_CTRL 0xac +#define PERST_N_ASSERT BIT(1) +#define PERST_N_AUTO_EN BIT(0) +#define PD_PCIE_CFG_0 0x3e8 +#define PCIE_FORCE_SHUTDOWN BIT(25) + +#define PCIE_SS_REG_BASE 0xE00 +#define APB_CLKFREQ_TIMEOUT 0x4 +#define BUSERR_EN BIT(12) +#define APB_TIMER_DIS BIT(10) +#define APB_TIMER_LIMIT GENMASK(31, 16) + +#define PE0_GEN_CTRL_3 0x58 +#define LTSSM_EN BIT(0) + +struct sprd_pcie_soc_data { + u32 syscon_offset; +}; + +static const struct sprd_pcie_soc_data ums9520_syscon_data = { + .syscon_offset = 0x1000, /* The offset of set/clear register */ +}; + +struct sprd_pcie { + u32 syscon_offset; + struct device *dev; + struct dw_pcie *pci; + struct regmap *aon_map; + struct regmap *pmu_map; + const struct sprd_pcie_soc_data *socdata; +}; + +enum sprd_pcie_syscon_type { + normal_syscon, /* it's not a set/clear register */ + set_syscon, /* set a set/clear register */ + clr_syscon, /* clear a set/clear register */ +}; + +static void sprd_pcie_buserr_enable(struct dw_pcie *pci) +{ + u32 val; + + val = dw_pcie_readl_dbi(pci, PCIE_SS_REG_BASE + APB_CLKFREQ_TIMEOUT); + val &= ~APB_TIMER_DIS; + val |= BUSERR_EN; + val |= APB_TIMER_LIMIT & (0x1f4 << 16); + dw_pcie_writel_dbi(pci, PCIE_SS_REG_BASE + APB_CLKFREQ_TIMEOUT, val); +} + +static void sprd_pcie_ltssm_enable(struct dw_pcie *pci, bool enable) +{ + u32 val; + + val = dw_pcie_readl_dbi(pci, PCIE_SS_REG_BASE + PE0_GEN_CTRL_3); + if (enable) + dw_pcie_writel_dbi(pci, PCIE_SS_REG_BASE + PE0_GEN_CTRL_3, + val | LTSSM_EN); + else + dw_pcie_writel_dbi(pci, PCIE_SS_REG_BASE + PE0_GEN_CTRL_3, + val & ~LTSSM_EN); +} + +static int sprd_pcie_syscon_set(struct sprd_pcie *ctrl, struct regmap *map, + u32 reg, u32 mask, u32 val, + enum sprd_pcie_syscon_type type) +{ + int ret = 0; + u32 read_val; + u32 offset = ctrl->syscon_offset; + struct device *dev = ctrl->pci->dev; + + /* + * Each set/clear register has three registers: + * reg: base register + * reg + offset: set register + * reg + offset * 2: clear register + */ + switch (type) { + case normal_syscon: + ret = regmap_read(map, reg, &read_val); + if (ret) { + dev_err(dev, "failed to read register 0x%x\n", reg); + return ret; + } + read_val &= ~mask; + read_val |= (val & mask); + ret = regmap_write(map, reg, read_val); + break; + case set_syscon: + reg = reg + offset; + ret = regmap_write(map, reg, val); + break; + case clr_syscon: + reg = reg + offset * 2; + ret = regmap_write(map, reg, val); + break; + default: + break; + } + + if (ret) + dev_err(dev, "failed to write register 0x%x\n", reg); + + return ret; +} + +static int sprd_pcie_perst_assert(struct sprd_pcie *ctrl) +{ + return sprd_pcie_syscon_set(ctrl, ctrl->pmu_map, SNPS_PCIE3_SLP_CTRL, + PERST_N_ASSERT, PERST_N_ASSERT, set_syscon); +} + +static int sprd_pcie_perst_deassert(struct sprd_pcie *ctrl) +{ + int ret; + + ret = sprd_pcie_syscon_set(ctrl, ctrl->pmu_map, SNPS_PCIE3_SLP_CTRL, + PERST_N_ASSERT, 0, clr_syscon); + usleep_range(2000, 3000); + + return ret; +} + +static int sprd_pcie_power_on(struct platform_device *pdev) +{ + int ret; + struct sprd_pcie *ctrl = platform_get_drvdata(pdev); + struct dw_pcie *pci = ctrl->pci; + + ret = sprd_pcie_syscon_set(ctrl, ctrl->aon_map, PD_PCIE_CFG_0, + PCIE_FORCE_SHUTDOWN, 0, clr_syscon); + if (ret) + return ret; + + ret = sprd_pcie_syscon_set(ctrl, ctrl->aon_map, IPA_ACCESS_CFG, + AON_ACCESS_PCIE_EN, AON_ACCESS_PCIE_EN, + set_syscon); + if (ret) + return ret; + + ret = sprd_pcie_perst_deassert(ctrl); + if (ret) + return ret; + + sprd_pcie_buserr_enable(pci); + sprd_pcie_ltssm_enable(pci, true); + + return ret; +} + +static int sprd_pcie_power_off(struct platform_device *pdev) +{ + struct sprd_pcie *ctrl = platform_get_drvdata(pdev); + struct dw_pcie *pci = ctrl->pci; + + sprd_pcie_ltssm_enable(pci, false); + + sprd_pcie_perst_assert(ctrl); + sprd_pcie_syscon_set(ctrl, ctrl->aon_map, PD_PCIE_CFG_0, + PCIE_FORCE_SHUTDOWN, PCIE_FORCE_SHUTDOWN, + set_syscon); + sprd_pcie_syscon_set(ctrl, ctrl->aon_map, IPA_ACCESS_CFG, + AON_ACCESS_PCIE_EN, 0, clr_syscon); + + return 0; +} + +static int sprd_add_pcie_port(struct platform_device *pdev) +{ + struct sprd_pcie *ctrl = platform_get_drvdata(pdev); + struct dw_pcie *pci = ctrl->pci; + struct pcie_port *pp = &pci->pp; + + return dw_pcie_host_init(pp); +} + +static int sprd_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct sprd_pcie *ctrl; + struct dw_pcie *pci; + int ret; + + ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL); + if (!ctrl) + return -ENOMEM; + + ctrl->socdata = + (struct sprd_pcie_soc_data *)of_device_get_match_data(dev); + if (!ctrl->socdata) { + dev_warn(dev, + "using the default set/clear register offset address"); + ctrl->syscon_offset = 0x1000; + } + ctrl->syscon_offset = ctrl->socdata->syscon_offset; + + ctrl->aon_map = syscon_regmap_lookup_by_phandle(dev->of_node, + "sprd, regmap-aon"); + if (IS_ERR(ctrl->aon_map)) { + dev_err(dev, "failed to get syscon regmap aon\n"); + ret = PTR_ERR(ctrl->aon_map); + goto err; + } + + ctrl->pmu_map = syscon_regmap_lookup_by_phandle(dev->of_node, + "sprd, regmap-pmu"); + if (IS_ERR(ctrl->pmu_map)) { + dev_err(dev, "failed to get syscon regmap pmu\n"); + ret = PTR_ERR(ctrl->pmu_map); + goto err; + } + + pci = ctrl->pci; + pci->dev = dev; + + platform_set_drvdata(pdev, ctrl); + + ret = sprd_pcie_power_on(pdev); + if (ret < 0) { + dev_err(dev, "failed to power on, return %d\n", + ret); + goto err_power_off; + } + + ret = sprd_add_pcie_port(pdev); + if (ret) { + dev_warn(dev, "failed to initialize RC controller\n"); + return ret; + } + + return 0; + +err_power_off: + sprd_pcie_power_off(pdev); +err: + return ret; +} + +static int sprd_pcie_remove(struct platform_device *pdev) +{ + sprd_pcie_power_off(pdev); + + return 0; +} + +static const struct of_device_id sprd_pcie_of_match[] = { + { + .compatible = "sprd,ums9520-pcie", + .data = &ums9520_syscon_data, + }, + {}, +}; + +static struct platform_driver sprd_pcie_driver = { + .probe = sprd_pcie_probe, + .remove = sprd_pcie_remove, + .driver = { + .name = "sprd-pcie", + .of_match_table = sprd_pcie_of_match, + }, +}; +module_platform_driver(sprd_pcie_driver); + +MODULE_DESCRIPTION("Unisoc PCIe host controller driver"); +MODULE_LICENSE("GPL"); -- 2.25.1