diff options
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-visconti.c')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-visconti.c | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-visconti.c b/drivers/pci/controller/dwc/pcie-visconti.c new file mode 100644 index 000000000..71026fefa --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-visconti.c @@ -0,0 +1,329 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DWC PCIe RC driver for Toshiba Visconti ARM SoC + * + * Copyright (C) 2021 Toshiba Electronic Device & Storage Corporation + * Copyright (C) 2021 TOSHIBA CORPORATION + * + * Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/gpio.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/of_platform.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/resource.h> +#include <linux/types.h> + +#include "pcie-designware.h" +#include "../../pci.h" + +struct visconti_pcie { + struct dw_pcie pci; + void __iomem *ulreg_base; + void __iomem *smu_base; + void __iomem *mpu_base; + struct clk *refclk; + struct clk *coreclk; + struct clk *auxclk; +}; + +#define PCIE_UL_REG_S_PCIE_MODE 0x00F4 +#define PCIE_UL_REG_S_PCIE_MODE_EP 0x00 +#define PCIE_UL_REG_S_PCIE_MODE_RC 0x04 + +#define PCIE_UL_REG_S_PERSTN_CTRL 0x00F8 +#define PCIE_UL_IOM_PCIE_PERSTN_I_EN BIT(3) +#define PCIE_UL_DIRECT_PERSTN_EN BIT(2) +#define PCIE_UL_PERSTN_OUT BIT(1) +#define PCIE_UL_DIRECT_PERSTN BIT(0) +#define PCIE_UL_REG_S_PERSTN_CTRL_INIT (PCIE_UL_IOM_PCIE_PERSTN_I_EN | \ + PCIE_UL_DIRECT_PERSTN_EN | \ + PCIE_UL_DIRECT_PERSTN) + +#define PCIE_UL_REG_S_PHY_INIT_02 0x0104 +#define PCIE_UL_PHY0_SRAM_EXT_LD_DONE BIT(0) + +#define PCIE_UL_REG_S_PHY_INIT_03 0x0108 +#define PCIE_UL_PHY0_SRAM_INIT_DONE BIT(0) + +#define PCIE_UL_REG_S_INT_EVENT_MASK1 0x0138 +#define PCIE_UL_CFG_PME_INT BIT(0) +#define PCIE_UL_CFG_LINK_EQ_REQ_INT BIT(1) +#define PCIE_UL_EDMA_INT0 BIT(2) +#define PCIE_UL_EDMA_INT1 BIT(3) +#define PCIE_UL_EDMA_INT2 BIT(4) +#define PCIE_UL_EDMA_INT3 BIT(5) +#define PCIE_UL_S_INT_EVENT_MASK1_ALL (PCIE_UL_CFG_PME_INT | \ + PCIE_UL_CFG_LINK_EQ_REQ_INT | \ + PCIE_UL_EDMA_INT0 | \ + PCIE_UL_EDMA_INT1 | \ + PCIE_UL_EDMA_INT2 | \ + PCIE_UL_EDMA_INT3) + +#define PCIE_UL_REG_S_SB_MON 0x0198 +#define PCIE_UL_REG_S_SIG_MON 0x019C +#define PCIE_UL_CORE_RST_N_MON BIT(0) + +#define PCIE_UL_REG_V_SII_DBG_00 0x0844 +#define PCIE_UL_REG_V_SII_GEN_CTRL_01 0x0860 +#define PCIE_UL_APP_LTSSM_ENABLE BIT(0) + +#define PCIE_UL_REG_V_PHY_ST_00 0x0864 +#define PCIE_UL_SMLH_LINK_UP BIT(0) + +#define PCIE_UL_REG_V_PHY_ST_02 0x0868 +#define PCIE_UL_S_DETECT_ACT 0x01 +#define PCIE_UL_S_L0 0x11 + +#define PISMU_CKON_PCIE 0x0038 +#define PISMU_CKON_PCIE_AUX_CLK BIT(1) +#define PISMU_CKON_PCIE_MSTR_ACLK BIT(0) + +#define PISMU_RSOFF_PCIE 0x0538 +#define PISMU_RSOFF_PCIE_ULREG_RST_N BIT(1) +#define PISMU_RSOFF_PCIE_PWR_UP_RST_N BIT(0) + +#define PCIE_MPU_REG_MP_EN 0x0 +#define MPU_MP_EN_DISABLE BIT(0) + +/* Access registers in PCIe ulreg */ +static void visconti_ulreg_writel(struct visconti_pcie *pcie, u32 val, u32 reg) +{ + writel_relaxed(val, pcie->ulreg_base + reg); +} + +static u32 visconti_ulreg_readl(struct visconti_pcie *pcie, u32 reg) +{ + return readl_relaxed(pcie->ulreg_base + reg); +} + +/* Access registers in PCIe smu */ +static void visconti_smu_writel(struct visconti_pcie *pcie, u32 val, u32 reg) +{ + writel_relaxed(val, pcie->smu_base + reg); +} + +/* Access registers in PCIe mpu */ +static void visconti_mpu_writel(struct visconti_pcie *pcie, u32 val, u32 reg) +{ + writel_relaxed(val, pcie->mpu_base + reg); +} + +static u32 visconti_mpu_readl(struct visconti_pcie *pcie, u32 reg) +{ + return readl_relaxed(pcie->mpu_base + reg); +} + +static int visconti_pcie_link_up(struct dw_pcie *pci) +{ + struct visconti_pcie *pcie = dev_get_drvdata(pci->dev); + void __iomem *addr = pcie->ulreg_base; + u32 val = readl_relaxed(addr + PCIE_UL_REG_V_PHY_ST_02); + + return !!(val & PCIE_UL_S_L0); +} + +static int visconti_pcie_start_link(struct dw_pcie *pci) +{ + struct visconti_pcie *pcie = dev_get_drvdata(pci->dev); + void __iomem *addr = pcie->ulreg_base; + u32 val; + int ret; + + visconti_ulreg_writel(pcie, PCIE_UL_APP_LTSSM_ENABLE, + PCIE_UL_REG_V_SII_GEN_CTRL_01); + + ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_02, + val, (val & PCIE_UL_S_L0), + 90000, 100000); + if (ret) + return ret; + + visconti_ulreg_writel(pcie, PCIE_UL_S_INT_EVENT_MASK1_ALL, + PCIE_UL_REG_S_INT_EVENT_MASK1); + + if (dw_pcie_link_up(pci)) { + val = visconti_mpu_readl(pcie, PCIE_MPU_REG_MP_EN); + visconti_mpu_writel(pcie, val & ~MPU_MP_EN_DISABLE, + PCIE_MPU_REG_MP_EN); + } + + return 0; +} + +static void visconti_pcie_stop_link(struct dw_pcie *pci) +{ + struct visconti_pcie *pcie = dev_get_drvdata(pci->dev); + u32 val; + + val = visconti_ulreg_readl(pcie, PCIE_UL_REG_V_SII_GEN_CTRL_01); + val &= ~PCIE_UL_APP_LTSSM_ENABLE; + visconti_ulreg_writel(pcie, val, PCIE_UL_REG_V_SII_GEN_CTRL_01); + + val = visconti_mpu_readl(pcie, PCIE_MPU_REG_MP_EN); + visconti_mpu_writel(pcie, val | MPU_MP_EN_DISABLE, PCIE_MPU_REG_MP_EN); +} + +/* + * In this SoC specification, the CPU bus outputs the offset value from + * 0x40000000 to the PCIe bus, so 0x40000000 is subtracted from the CPU + * bus address. This 0x40000000 is also based on io_base from DT. + */ +static u64 visconti_pcie_cpu_addr_fixup(struct dw_pcie *pci, u64 cpu_addr) +{ + struct dw_pcie_rp *pp = &pci->pp; + + return cpu_addr & ~pp->io_base; +} + +static const struct dw_pcie_ops dw_pcie_ops = { + .cpu_addr_fixup = visconti_pcie_cpu_addr_fixup, + .link_up = visconti_pcie_link_up, + .start_link = visconti_pcie_start_link, + .stop_link = visconti_pcie_stop_link, +}; + +static int visconti_pcie_host_init(struct dw_pcie_rp *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct visconti_pcie *pcie = dev_get_drvdata(pci->dev); + void __iomem *addr; + int err; + u32 val; + + visconti_smu_writel(pcie, + PISMU_CKON_PCIE_AUX_CLK | PISMU_CKON_PCIE_MSTR_ACLK, + PISMU_CKON_PCIE); + ndelay(250); + + visconti_smu_writel(pcie, PISMU_RSOFF_PCIE_ULREG_RST_N, + PISMU_RSOFF_PCIE); + visconti_ulreg_writel(pcie, PCIE_UL_REG_S_PCIE_MODE_RC, + PCIE_UL_REG_S_PCIE_MODE); + + val = PCIE_UL_REG_S_PERSTN_CTRL_INIT; + visconti_ulreg_writel(pcie, val, PCIE_UL_REG_S_PERSTN_CTRL); + udelay(100); + + val |= PCIE_UL_PERSTN_OUT; + visconti_ulreg_writel(pcie, val, PCIE_UL_REG_S_PERSTN_CTRL); + udelay(100); + + visconti_smu_writel(pcie, PISMU_RSOFF_PCIE_PWR_UP_RST_N, + PISMU_RSOFF_PCIE); + + addr = pcie->ulreg_base + PCIE_UL_REG_S_PHY_INIT_03; + err = readl_relaxed_poll_timeout(addr, val, + (val & PCIE_UL_PHY0_SRAM_INIT_DONE), + 100, 1000); + if (err) + return err; + + visconti_ulreg_writel(pcie, PCIE_UL_PHY0_SRAM_EXT_LD_DONE, + PCIE_UL_REG_S_PHY_INIT_02); + + addr = pcie->ulreg_base + PCIE_UL_REG_S_SIG_MON; + return readl_relaxed_poll_timeout(addr, val, + (val & PCIE_UL_CORE_RST_N_MON), 100, + 1000); +} + +static const struct dw_pcie_host_ops visconti_pcie_host_ops = { + .host_init = visconti_pcie_host_init, +}; + +static int visconti_get_resources(struct platform_device *pdev, + struct visconti_pcie *pcie) +{ + struct device *dev = &pdev->dev; + + pcie->ulreg_base = devm_platform_ioremap_resource_byname(pdev, "ulreg"); + if (IS_ERR(pcie->ulreg_base)) + return PTR_ERR(pcie->ulreg_base); + + pcie->smu_base = devm_platform_ioremap_resource_byname(pdev, "smu"); + if (IS_ERR(pcie->smu_base)) + return PTR_ERR(pcie->smu_base); + + pcie->mpu_base = devm_platform_ioremap_resource_byname(pdev, "mpu"); + if (IS_ERR(pcie->mpu_base)) + return PTR_ERR(pcie->mpu_base); + + pcie->refclk = devm_clk_get(dev, "ref"); + if (IS_ERR(pcie->refclk)) + return dev_err_probe(dev, PTR_ERR(pcie->refclk), + "Failed to get ref clock\n"); + + pcie->coreclk = devm_clk_get(dev, "core"); + if (IS_ERR(pcie->coreclk)) + return dev_err_probe(dev, PTR_ERR(pcie->coreclk), + "Failed to get core clock\n"); + + pcie->auxclk = devm_clk_get(dev, "aux"); + if (IS_ERR(pcie->auxclk)) + return dev_err_probe(dev, PTR_ERR(pcie->auxclk), + "Failed to get aux clock\n"); + + return 0; +} + +static int visconti_add_pcie_port(struct visconti_pcie *pcie, + struct platform_device *pdev) +{ + struct dw_pcie *pci = &pcie->pci; + struct dw_pcie_rp *pp = &pci->pp; + + pp->irq = platform_get_irq_byname(pdev, "intr"); + if (pp->irq < 0) + return pp->irq; + + pp->ops = &visconti_pcie_host_ops; + + return dw_pcie_host_init(pp); +} + +static int visconti_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct visconti_pcie *pcie; + struct dw_pcie *pci; + int ret; + + pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL); + if (!pcie) + return -ENOMEM; + + pci = &pcie->pci; + pci->dev = dev; + pci->ops = &dw_pcie_ops; + + ret = visconti_get_resources(pdev, pcie); + if (ret) + return ret; + + platform_set_drvdata(pdev, pcie); + + return visconti_add_pcie_port(pcie, pdev); +} + +static const struct of_device_id visconti_pcie_match[] = { + { .compatible = "toshiba,visconti-pcie" }, + {}, +}; + +static struct platform_driver visconti_pcie_driver = { + .probe = visconti_pcie_probe, + .driver = { + .name = "visconti-pcie", + .of_match_table = visconti_pcie_match, + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(visconti_pcie_driver); |