--- /dev/null
+// 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 pcie_port *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 pcie_port *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 pcie_port *pp = &pci->pp;
+ struct device *dev = &pdev->dev;
+
+ pp->irq = platform_get_irq_byname(pdev, "intr");
+ if (pp->irq < 0) {
+ dev_err(dev, "Interrupt intr is missing");
+ 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);
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