diff mbox series

[v4,2/3] PCI: visconti: Add Toshiba Visconti PCIe host controller driver

Message ID 20210629234952.306578-3-nobuhiro1.iwamatsu@toshiba.co.jp (mailing list archive)
State New, archived
Headers show
Series Visconti: Add Toshiba Visconti PCIe host controller driver | expand

Commit Message

Nobuhiro Iwamatsu June 29, 2021, 11:49 p.m. UTC 
Add support to PCIe RC controller on Toshiba Visconti ARM SoCs. PCIe
controller is based of Synopsys DesignWare PCIe core.

This patch does not yet use the clock framework to control the clock.
This will be replaced in the future.

Signed-off-by: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
---
 drivers/pci/controller/dwc/Kconfig         |   9 +
 drivers/pci/controller/dwc/Makefile        |   1 +
 drivers/pci/controller/dwc/pcie-visconti.c | 360 +++++++++++++++++++++
 3 files changed, 370 insertions(+)
 create mode 100644 drivers/pci/controller/dwc/pcie-visconti.c

Comments

Rob Herring July 1, 2021, 3:43 p.m. UTC | #1 
On Tue, Jun 29, 2021 at 5:50 PM Nobuhiro Iwamatsu
<nobuhiro1.iwamatsu@toshiba.co.jp> wrote:
>
> Add support to PCIe RC controller on Toshiba Visconti ARM SoCs. PCIe
> controller is based of Synopsys DesignWare PCIe core.
>
> This patch does not yet use the clock framework to control the clock.
> This will be replaced in the future.
>
> Signed-off-by: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>
> Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
> ---
>  drivers/pci/controller/dwc/Kconfig         |   9 +
>  drivers/pci/controller/dwc/Makefile        |   1 +
>  drivers/pci/controller/dwc/pcie-visconti.c | 360 +++++++++++++++++++++
>  3 files changed, 370 insertions(+)
>  create mode 100644 drivers/pci/controller/dwc/pcie-visconti.c
>
> diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
> index 423d35872ce4..7c3dcb86fcad 100644
> --- a/drivers/pci/controller/dwc/Kconfig
> +++ b/drivers/pci/controller/dwc/Kconfig
> @@ -286,6 +286,15 @@ config PCIE_TEGRA194_EP
>           in order to enable device-specific features PCIE_TEGRA194_EP must be
>           selected. This uses the DesignWare core.
>
> +config PCIE_VISCONTI_HOST
> +       bool "Toshiba Visconti PCIe controllers"
> +       depends on ARCH_VISCONTI || COMPILE_TEST
> +       depends on PCI_MSI_IRQ_DOMAIN
> +       select PCIE_DW_HOST
> +       help
> +         Say Y here if you want PCIe controller support on Toshiba Visconti SoC.
> +         This driver supports TMPV7708 SoC.
> +
>  config PCIE_UNIPHIER
>         bool "Socionext UniPhier PCIe host controllers"
>         depends on ARCH_UNIPHIER || COMPILE_TEST
> diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
> index eca805c1a023..0b569d54deb3 100644
> --- a/drivers/pci/controller/dwc/Makefile
> +++ b/drivers/pci/controller/dwc/Makefile
> @@ -20,6 +20,7 @@ obj-$(CONFIG_PCIE_HISI_STB) += pcie-histb.o
>  obj-$(CONFIG_PCI_MESON) += pci-meson.o
>  obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o
>  obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o
> +obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.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-visconti.c b/drivers/pci/controller/dwc/pcie-visconti.c
> new file mode 100644
> index 000000000000..1e1caa2ba1b6
> --- /dev/null
> +++ b/drivers/pci/controller/dwc/pcie-visconti.c
> @@ -0,0 +1,360 @@
> +// 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)
> +
> +#define PCIE_BUS_OFFSET                        0x40000000
> +
> +/* 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;
> +       int ret;
> +       u32 val;
> +
> +       /* wait for linkup of phy link layer */
> +       ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_00,
> +                                        val, (val & PCIE_UL_SMLH_LINK_UP),
> +                                        90000, 100000);

This function is really supposed to be 'is the link up or not', not
'wait for link up' as that is what the caller does. Isn't link up just
all 3 register bits are set? And it is possible for the 3rd bit
(PCIE_UL_S_L0) to be set without the first 2 bits set? IOW, can't you
just check PCIE_UL_S_L0?

> +       if (ret)
> +               return 0;
> +
> +       /* wait for linkup of data link layer */
> +       ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_02,
> +                                        val, (val & PCIE_UL_S_DETECT_ACT),
> +                                        90000, 100000);
> +       if (ret)
> +               return 0;
> +
> +       /* wait for LTSSM Status */
> +       ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_02,
> +                                        val, (val & PCIE_UL_S_L0),
> +                                        90000, 100000);
> +       if (ret)
> +               return 0;
> +       return 1;
> +}
> +
> +static int visconti_pcie_start_link(struct dw_pcie *pci)
> +{
> +       struct visconti_pcie *pcie = dev_get_drvdata(pci->dev);
> +
> +       visconti_ulreg_writel(pcie, PCIE_UL_APP_LTSSM_ENABLE,
> +                             PCIE_UL_REG_V_SII_GEN_CTRL_01);
> +
> +       if (dw_pcie_link_up(pci)) {
> +               u32 val;
> +
> +               val = visconti_mpu_readl(pcie, PCIE_MPU_REG_MP_EN);
> +               visconti_mpu_writel(pcie, val & ~MPU_MP_EN_DISABLE,
> +                                   PCIE_MPU_REG_MP_EN);
> +               visconti_ulreg_writel(pcie, PCIE_UL_S_INT_EVENT_MASK1_ALL,
> +                                     PCIE_UL_REG_S_INT_EVENT_MASK1);

Do these really have to be set after link up?

> +       }
> +
> +       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_power_on(struct visconti_pcie *pcie)
> +{
> +       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 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);
> +
> +       return visconti_pcie_power_on(pcie);

This function doesn't do anything but call visconti_pcie_power_on().
Just collapse to 1 function.

> +}
> +
> +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;
> +
> +       pci->link_gen = of_pci_get_max_link_speed(pdev->dev.of_node);

The common DWC code reads this for you now. You only need to set it to
default. See other drivers for examples.

> +       if (pci->link_gen < 0 || pci->link_gen > 3) {
> +               pci->link_gen = 3;
> +               dev_dbg(dev, "Applied default link speed\n");
> +       }
> +
> +       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);
> --
> 2.32.0
>
Nobuhiro Iwamatsu July 20, 2021, 10:56 p.m. UTC | #2 
Hi,

Thanks for your review.

On Thu, Jul 01, 2021 at 09:43:49AM -0600, Rob Herring wrote:
> On Tue, Jun 29, 2021 at 5:50 PM Nobuhiro Iwamatsu
> <nobuhiro1.iwamatsu@toshiba.co.jp> wrote:
> >
> > Add support to PCIe RC controller on Toshiba Visconti ARM SoCs. PCIe
> > controller is based of Synopsys DesignWare PCIe core.
> >
> > This patch does not yet use the clock framework to control the clock.
> > This will be replaced in the future.
> >
> > Signed-off-by: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>
> > Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
> > ---
> >  drivers/pci/controller/dwc/Kconfig         |   9 +
> >  drivers/pci/controller/dwc/Makefile        |   1 +
> >  drivers/pci/controller/dwc/pcie-visconti.c | 360 +++++++++++++++++++++
> >  3 files changed, 370 insertions(+)
> >  create mode 100644 drivers/pci/controller/dwc/pcie-visconti.c
> >
> > diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
> > index 423d35872ce4..7c3dcb86fcad 100644
> > --- a/drivers/pci/controller/dwc/Kconfig
> > +++ b/drivers/pci/controller/dwc/Kconfig
> > @@ -286,6 +286,15 @@ config PCIE_TEGRA194_EP
> >           in order to enable device-specific features PCIE_TEGRA194_EP must be
> >           selected. This uses the DesignWare core.
> >
> > +config PCIE_VISCONTI_HOST
> > +       bool "Toshiba Visconti PCIe controllers"
> > +       depends on ARCH_VISCONTI || COMPILE_TEST
> > +       depends on PCI_MSI_IRQ_DOMAIN
> > +       select PCIE_DW_HOST
> > +       help
> > +         Say Y here if you want PCIe controller support on Toshiba Visconti SoC.
> > +         This driver supports TMPV7708 SoC.
> > +
> >  config PCIE_UNIPHIER
> >         bool "Socionext UniPhier PCIe host controllers"
> >         depends on ARCH_UNIPHIER || COMPILE_TEST
> > diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
> > index eca805c1a023..0b569d54deb3 100644
> > --- a/drivers/pci/controller/dwc/Makefile
> > +++ b/drivers/pci/controller/dwc/Makefile
> > @@ -20,6 +20,7 @@ obj-$(CONFIG_PCIE_HISI_STB) += pcie-histb.o
> >  obj-$(CONFIG_PCI_MESON) += pci-meson.o
> >  obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o
> >  obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o
> > +obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.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-visconti.c b/drivers/pci/controller/dwc/pcie-visconti.c
> > new file mode 100644
> > index 000000000000..1e1caa2ba1b6
> > --- /dev/null
> > +++ b/drivers/pci/controller/dwc/pcie-visconti.c
> > @@ -0,0 +1,360 @@
> > +// 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)
> > +
> > +#define PCIE_BUS_OFFSET                        0x40000000
> > +
> > +/* 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;
> > +       int ret;
> > +       u32 val;
> > +
> > +       /* wait for linkup of phy link layer */
> > +       ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_00,
> > +                                        val, (val & PCIE_UL_SMLH_LINK_UP),
> > +                                        90000, 100000);
> 
> This function is really supposed to be 'is the link up or not', not
> 'wait for link up' as that is what the caller does. Isn't link up just
> all 3 register bits are set? And it is possible for the 3rd bit
> (PCIE_UL_S_L0) to be set without the first 2 bits set? IOW, can't you
> just check PCIE_UL_S_L0?

I mistook in using this function.
As you wrote, there is no problem in checking PCIE_UL_S_L0. I will fix it.

> 
> > +       if (ret)
> > +               return 0;
> > +
> > +       /* wait for linkup of data link layer */
> > +       ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_02,
> > +                                        val, (val & PCIE_UL_S_DETECT_ACT),
> > +                                        90000, 100000);
> > +       if (ret)
> > +               return 0;
> > +
> > +       /* wait for LTSSM Status */
> > +       ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_02,
> > +                                        val, (val & PCIE_UL_S_L0),
> > +                                        90000, 100000);
> > +       if (ret)
> > +               return 0;
> > +       return 1;
> > +}
> > +
> > +static int visconti_pcie_start_link(struct dw_pcie *pci)
> > +{
> > +       struct visconti_pcie *pcie = dev_get_drvdata(pci->dev);
> > +
> > +       visconti_ulreg_writel(pcie, PCIE_UL_APP_LTSSM_ENABLE,
> > +                             PCIE_UL_REG_V_SII_GEN_CTRL_01);
> > +
> > +       if (dw_pcie_link_up(pci)) {
> > +               u32 val;
> > +
> > +               val = visconti_mpu_readl(pcie, PCIE_MPU_REG_MP_EN);
> > +               visconti_mpu_writel(pcie, val & ~MPU_MP_EN_DISABLE,
> > +                                   PCIE_MPU_REG_MP_EN);
> > +               visconti_ulreg_writel(pcie, PCIE_UL_S_INT_EVENT_MASK1_ALL,
> > +                                     PCIE_UL_REG_S_INT_EVENT_MASK1);
> 
> Do these really have to be set after link up?

Indeed, I can move this before dw_pcie_link_up().
I will fix this.

> 
> > +       }
> > +
> > +       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_power_on(struct visconti_pcie *pcie)
> > +{
> > +       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 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);
> > +
> > +       return visconti_pcie_power_on(pcie);
> 
> This function doesn't do anything but call visconti_pcie_power_on().
> Just collapse to 1 function.
> 

OK, I will move the contents of visconti_pcie_power_on to
visconti_pcie_host_init.

> > +}
> > +
> > +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;
> > +
> > +       pci->link_gen = of_pci_get_max_link_speed(pdev->dev.of_node);
> 
> The common DWC code reads this for you now. You only need to set it to
> default. See other drivers for examples.

I don't need this code by using DT. Remove these codes.

Best regards,
  Nobuhiro
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 423d35872ce4..7c3dcb86fcad 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -286,6 +286,15 @@  config PCIE_TEGRA194_EP
 	  in order to enable device-specific features PCIE_TEGRA194_EP must be
 	  selected. This uses the DesignWare core.
 
+config PCIE_VISCONTI_HOST
+	bool "Toshiba Visconti PCIe controllers"
+	depends on ARCH_VISCONTI || COMPILE_TEST
+	depends on PCI_MSI_IRQ_DOMAIN
+	select PCIE_DW_HOST
+	help
+	  Say Y here if you want PCIe controller support on Toshiba Visconti SoC.
+	  This driver supports TMPV7708 SoC.
+
 config PCIE_UNIPHIER
 	bool "Socionext UniPhier PCIe host controllers"
 	depends on ARCH_UNIPHIER || COMPILE_TEST
diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
index eca805c1a023..0b569d54deb3 100644
--- a/drivers/pci/controller/dwc/Makefile
+++ b/drivers/pci/controller/dwc/Makefile
@@ -20,6 +20,7 @@  obj-$(CONFIG_PCIE_HISI_STB) += pcie-histb.o
 obj-$(CONFIG_PCI_MESON) += pci-meson.o
 obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o
 obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o
+obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.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-visconti.c b/drivers/pci/controller/dwc/pcie-visconti.c
new file mode 100644
index 000000000000..1e1caa2ba1b6
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-visconti.c
@@ -0,0 +1,360 @@ 
+// 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)
+
+#define PCIE_BUS_OFFSET			0x40000000
+
+/* 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;
+	int ret;
+	u32 val;
+
+	/* wait for linkup of phy link layer */
+	ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_00,
+					 val, (val & PCIE_UL_SMLH_LINK_UP),
+					 90000, 100000);
+	if (ret)
+		return 0;
+
+	/* wait for linkup of data link layer */
+	ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_02,
+					 val, (val & PCIE_UL_S_DETECT_ACT),
+					 90000, 100000);
+	if (ret)
+		return 0;
+
+	/* wait for LTSSM Status */
+	ret = readl_relaxed_poll_timeout(addr + PCIE_UL_REG_V_PHY_ST_02,
+					 val, (val & PCIE_UL_S_L0),
+					 90000, 100000);
+	if (ret)
+		return 0;
+	return 1;
+}
+
+static int visconti_pcie_start_link(struct dw_pcie *pci)
+{
+	struct visconti_pcie *pcie = dev_get_drvdata(pci->dev);
+
+	visconti_ulreg_writel(pcie, PCIE_UL_APP_LTSSM_ENABLE,
+			      PCIE_UL_REG_V_SII_GEN_CTRL_01);
+
+	if (dw_pcie_link_up(pci)) {
+		u32 val;
+
+		val = visconti_mpu_readl(pcie, PCIE_MPU_REG_MP_EN);
+		visconti_mpu_writel(pcie, val & ~MPU_MP_EN_DISABLE,
+				    PCIE_MPU_REG_MP_EN);
+		visconti_ulreg_writel(pcie, PCIE_UL_S_INT_EVENT_MASK1_ALL,
+				      PCIE_UL_REG_S_INT_EVENT_MASK1);
+	}
+
+	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_power_on(struct visconti_pcie *pcie)
+{
+	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 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);
+
+	return visconti_pcie_power_on(pcie);
+}
+
+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;
+
+	pci->link_gen = of_pci_get_max_link_speed(pdev->dev.of_node);
+	if (pci->link_gen < 0 || pci->link_gen > 3) {
+		pci->link_gen = 3;
+		dev_dbg(dev, "Applied default link speed\n");
+	}
+
+	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);