Re: [PATCH v5 4/7] phy: starfive: Add JH7110 PCIE 2.0 PHY driver

Roger Quadros
2023-04-24T09:23:27Z

On 20/04/2023 14:00, Minda Chen wrote:
> Add Starfive JH7110 SoC PCIe 2.0 PHY driver support.
> PCIe 2.0 PHY default connect to PCIe controller.
> But pcie0 PHY can connect to USB 3.0 controlller.

s/controlller/controller

>
> Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
> ---
> MAINTAINERS | 4 +-
> drivers/phy/starfive/Kconfig | 11 ++
> drivers/phy/starfive/Makefile | 1 +
> drivers/phy/starfive/phy-jh7110-pcie.c | 202 +++++++++++++++++++++++++
> 4 files changed, 217 insertions(+), 1 deletion(-)
> create mode 100644 drivers/phy/starfive/phy-jh7110-pcie.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index c09ea66dcd5a..8e0f755ba91b 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -19968,10 +19968,12 @@ M: William Qiu <william.qiu@starfivetech.com>
> S: Supported
> F: Documentation/devicetree/bindings/soc/starfive/starfive,jh7110-syscon.yaml
>
> -STARFIVE JH71X0 USB PHY DRIVER
> +STARFIVE JH71X0 PCIE AND USB PHY DRIVER
> M: Minda Chen <minda.chen@starfivetech.com>
> S: Supported
> +F: Documentation/devicetree/bindings/phy/starfive,jh7110-pcie-phy.yaml
> F: Documentation/devicetree/bindings/phy/starfive,jh7110-usb-phy.yaml
> +F: drivers/phy/starfive/phy-jh7110-pcie.c
> F: drivers/phy/starfive/phy-jh7110-usb.c
>
> STATIC BRANCH/CALL
> diff --git a/drivers/phy/starfive/Kconfig b/drivers/phy/starfive/Kconfig
> index 2c013c390dee..c21c21d284a6 100644
> --- a/drivers/phy/starfive/Kconfig
> +++ b/drivers/phy/starfive/Kconfig
> @@ -12,6 +12,17 @@ config PHY_STARFIVE_DPHY_RX
> system. If M is selected, the module will be called
> phy-starfive-dphy-rx.
>
> +config PHY_STARFIVE_JH7110_PCIE
> + tristate "Starfive JH7110 PCIE 2.0/USB 3.0 PHY support"
> + depends on USB_SUPPORT

What if system has PCIE and no USB. Then they can't use this PHY
as it cannot be built?

> + select GENERIC_PHY
> + select USB_PHY
> + help
> + Enable this to support the StarFive PCIe 2.0 PHY,
> + or used as USB 3.0 PHY.
> + If M is selected, the module will be called
> + phy-jh7110-pcie.ko.
> +
> config PHY_STARFIVE_JH7110_USB
> tristate "Starfive JH7110 USB 2.0 PHY support"
> depends on USB_SUPPORT
> diff --git a/drivers/phy/starfive/Makefile b/drivers/phy/starfive/Makefile
> index 176443852f4d..03a55aad53a2 100644
> --- a/drivers/phy/starfive/Makefile
> +++ b/drivers/phy/starfive/Makefile
> @@ -1,3 +1,4 @@
> # SPDX-License-Identifier: GPL-2.0
> obj-$(CONFIG_PHY_STARFIVE_DPHY_RX) += phy-starfive-dphy-rx.o
> +obj-$(CONFIG_PHY_STARFIVE_JH7110_PCIE) += phy-jh7110-pcie.o
> obj-$(CONFIG_PHY_STARFIVE_JH7110_USB) += phy-jh7110-usb.o
> diff --git a/drivers/phy/starfive/phy-jh7110-pcie.c b/drivers/phy/starfive/phy-jh7110-pcie.c
> new file mode 100644
> index 000000000000..fe029daef62e
> --- /dev/null
> +++ b/drivers/phy/starfive/phy-jh7110-pcie.c
> @@ -0,0 +1,202 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * StarFive JH7110 PCIe 2.0 PHY driver
> + *
> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
> + * Author: Minda Chen <minda.chen@starfivetech.com>
> + */
> +
> +#include <linux/bits.h>
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +#define PCIE_KVCO_LEVEL_OFF (0x28)
> +#define PCIE_USB3_PHY_PLL_CTL_OFF (0x7c)
> +#define PCIE_KVCO_TUNE_SIGNAL_OFF (0x80)

Brackets not required.

> +#define PCIE_USB3_PHY_ENABLE BIT(4)
> +#define PHY_KVCO_FINE_TUNE_LEVEL 0x91
> +#define PHY_KVCO_FINE_TUNE_SIGNALS 0xc
> +
> +#define USB_PDRSTN_SPLIT BIT(17)
> +
> +#define PCIE_PHY_MODE BIT(20)
> +#define PCIE_PHY_MODE_MASK GENMASK(21, 20)
> +#define PCIE_USB3_BUS_WIDTH_MASK GENMASK(3, 2)
> +#define PCIE_USB3_RATE_MASK GENMASK(6, 5)
> +#define PCIE_USB3_RX_STANDBY_MASK BIT(7)
> +#define PCIE_USB3_PHY_ENABLE BIT(4)
> +
> +struct jh7110_pcie_phy {
> + struct phy *phy;
> + struct regmap *stg_syscon;
> + struct regmap *sys_syscon;
> + void __iomem *regs;
> + u32 sys_phy_connect;
> + u32 stg_pcie_mode;
> + u32 stg_pcie_usb;
> + enum phy_mode mode;
> +};
> +
> +static int jh7110_usb3_mode_set(struct jh7110_pcie_phy *data)
> +{
> + if (!data->stg_syscon || !data->sys_syscon) {
> + dev_info(&data->phy->dev, "don't support usb3 mode\n");

s/don't/doesn't

dev_err()

> + return -EINVAL;
> + }
> +
> + regmap_update_bits(data->stg_syscon, data->stg_pcie_mode,
> + PCIE_PHY_MODE_MASK, PCIE_PHY_MODE);
> + regmap_update_bits(data->stg_syscon, data->stg_pcie_usb,
> + PCIE_USB3_BUS_WIDTH_MASK, 0);
> + regmap_update_bits(data->stg_syscon, data->stg_pcie_usb,
> + PCIE_USB3_RATE_MASK, 0);
> + regmap_update_bits(data->stg_syscon, data->stg_pcie_usb,
> + PCIE_USB3_RX_STANDBY_MASK, 0);
> + regmap_update_bits(data->stg_syscon, data->stg_pcie_usb,
> + PCIE_USB3_PHY_ENABLE, PCIE_USB3_PHY_ENABLE);
> +
> + /* Connect usb 3.0 phy mode */
> + regmap_update_bits(data->sys_syscon, data->sys_phy_connect,
> + USB_PDRSTN_SPLIT, 0);
> +
> + /* Configuare spread-spectrum mode: down-spread-spectrum */
> + writel(PCIE_USB3_PHY_ENABLE, data->regs + PCIE_USB3_PHY_PLL_CTL_OFF);
> +
> + return 0;
> +}
> +
> +static void jh7110_pcie_mode_set(struct jh7110_pcie_phy *phy)
> +{
> + /* PCIe Multi-PHY PLL KVCO Gain fine tune settings: */
> + writel(PHY_KVCO_FINE_TUNE_LEVEL, phy->regs + PCIE_KVCO_LEVEL_OFF);
> + writel(PHY_KVCO_FINE_TUNE_SIGNALS, phy->regs + PCIE_KVCO_TUNE_SIGNAL_OFF);

In cases where PHY can be connected to both USB and PCIe don't you have to
make sure PHY is connected to PCIe controller by setting data->sys_syscon
and data->stg_syscon appropriately?

> +}
> +
> +static int jh7110_pcie_phy_set_mode(struct phy *_phy,
> + enum phy_mode mode, int submode)
> +{
> + struct jh7110_pcie_phy *phy = phy_get_drvdata(_phy);
> + int ret;
> +
> + if (mode == phy->mode)
> + return 0;
> +
> + switch (mode) {
> + case PHY_MODE_USB_HOST:
> + case PHY_MODE_USB_DEVICE:
> + case PHY_MODE_USB_OTG:
> + ret = jh7110_usb3_mode_set(phy);
> + if (ret)
> + return ret;
> + break;
> + case PHY_MODE_PCIE:
> + jh7110_pcie_mode_set(phy);
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + dev_info(&_phy->dev, "Changing phy mode to %d\n", mode);

dev_dbg()?

> + phy->mode = mode;
> +
> + return 0;
> +}
> +
> +static int jh7110_pcie_phy_init(struct phy *_phy)
> +{
> + return 0;
> +}
> +
> +static int jh7110_pcie_phy_exit(struct phy *_phy)
> +{
> + return 0;
> +}
> +
> +static const struct phy_ops jh7110_pcie_phy_ops = {
> + .init = jh7110_pcie_phy_init,
> + .exit = jh7110_pcie_phy_exit,

As you are not doing anything in init/exit, you don't have to set them.

> + .set_mode = jh7110_pcie_phy_set_mode,
> + .owner = THIS_MODULE,
> +};
> +
> +static int jh7110_pcie_phy_probe(struct platform_device *pdev)
> +{
> + struct jh7110_pcie_phy *phy;
> + struct device *dev = &pdev->dev;
> + struct phy_provider *phy_provider;
> + u32 args[2];
> +
> + phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
> + if (!phy)
> + return -ENOMEM;
> +
> + phy->regs = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(phy->regs))
> + return PTR_ERR(phy->regs);
> +
> + phy->phy = devm_phy_create(dev, NULL, &jh7110_pcie_phy_ops);
> + if (IS_ERR(phy->phy))
> + return dev_err_probe(dev, PTR_ERR(phy->regs),
> + "Failed to map phy base\n");
> +
> + phy->sys_syscon =
> + syscon_regmap_lookup_by_phandle_args(pdev->dev.of_node,
> + "starfive,sys-syscon",
> + 1, args);
> +
> + if (!IS_ERR_OR_NULL(phy->sys_syscon))
> + phy->sys_phy_connect = args[0];
> + else
> + phy->sys_syscon = NULL;
> +
> + phy->stg_syscon =
> + syscon_regmap_lookup_by_phandle_args(pdev->dev.of_node,
> + "starfive,stg-syscon",
> + 2, args);
> +
> + if (!IS_ERR_OR_NULL(phy->stg_syscon)) {
> + phy->stg_pcie_mode = args[0];
> + phy->stg_pcie_usb = args[1];
> + } else {
> + phy->stg_syscon = NULL;
> + }
> +
> + platform_set_drvdata(pdev, phy);
> + phy_set_drvdata(phy->phy, phy);
> + phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +
> + return PTR_ERR_OR_ZERO(phy_provider);
> +}
> +
> +static int jh7110_pcie_phy_remove(struct platform_device *pdev)
> +{
> + platform_set_drvdata(pdev, NULL);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id jh7110_pcie_phy_of_match[] = {
> + { .compatible = "starfive,jh7110-pcie-phy" },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, jh7110_pcie_phy_of_match);
> +
> +static struct platform_driver jh7110_pcie_phy_driver = {
> + .probe = jh7110_pcie_phy_probe,
> + .remove = jh7110_pcie_phy_remove,
> + .driver = {
> + .of_match_table = jh7110_pcie_phy_of_match,
> + .name = "jh7110-pcie-phy",
> + }
> +};
> +module_platform_driver(jh7110_pcie_phy_driver);
> +
> +MODULE_DESCRIPTION("StarFive JH7110 PCIe 2.0 PHY driver");
> +MODULE_AUTHOR("Minda Chen <minda.chen@starfivetech.com>");
> +MODULE_LICENSE("GPL");

cheers,
-roger