On Thu 16 Jan 2020 at 12:18, Remi Pommarel <repk@xxxxxxxxxxxx> wrote:
> This adds support for the PCI PHY found in the Amlogic AXG SoC Family.
> This will allow to mutualize code in pci-meson.c between AXG and G12A
> SoC.
>
> This PHY can chain and use an optional analog PHY, which is used on
> AXG platform to have reliable PCIe communication.
>
> Signed-off-by: Remi Pommarel <repk@xxxxxxxxxxxx>
> ---
> drivers/phy/amlogic/Kconfig | 11 ++
> drivers/phy/amlogic/Makefile | 1 +
> drivers/phy/amlogic/phy-meson-axg-pcie.c | 192 +++++++++++++++++++++++
> 3 files changed, 204 insertions(+)
> create mode 100644 drivers/phy/amlogic/phy-meson-axg-pcie.c
>
> diff --git a/drivers/phy/amlogic/Kconfig b/drivers/phy/amlogic/Kconfig
> index 8c9cf2403591..71801e30d601 100644
> --- a/drivers/phy/amlogic/Kconfig
> +++ b/drivers/phy/amlogic/Kconfig
> @@ -60,6 +60,17 @@ config PHY_MESON_G12A_USB3_PCIE
> in Meson G12A SoCs.
> If unsure, say N.
>
> +config PHY_MESON_AXG_PCIE
> + tristate "Meson AXG PCIE PHY driver"
> + default ARCH_MESON
> + depends on OF && (ARCH_MESON || COMPILE_TEST)
> + select GENERIC_PHY
> + select REGMAP_MMIO
> + help
> + Enable this to support the Meson MIPI + PCIE PHY found
> + in Meson AXG SoCs.
> + If unsure, say N.
> +
> config PHY_MESON_AXG_MIPI_PCIE_ANALOG
> tristate "Meson AXG MIPI + PCIE analog PHY driver"
> default ARCH_MESON
> diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
> index 0aecf92d796a..e2baa133f7af 100644
> --- a/drivers/phy/amlogic/Makefile
> +++ b/drivers/phy/amlogic/Makefile
> @@ -4,4 +4,5 @@ obj-$(CONFIG_PHY_MESON_GXL_USB2) += phy-meson-gxl-usb2.o
> obj-$(CONFIG_PHY_MESON_G12A_USB2) += phy-meson-g12a-usb2.o
> obj-$(CONFIG_PHY_MESON_GXL_USB3) += phy-meson-gxl-usb3.o
> obj-$(CONFIG_PHY_MESON_G12A_USB3_PCIE) += phy-meson-g12a-usb3-pcie.o
> +obj-$(CONFIG_PHY_MESON_AXG_PCIE) += phy-meson-axg-pcie.o
> obj-$(CONFIG_PHY_MESON_AXG_MIPI_PCIE_ANALOG) += phy-meson-axg-mipi-pcie-analog.o
> diff --git a/drivers/phy/amlogic/phy-meson-axg-pcie.c b/drivers/phy/amlogic/phy-meson-axg-pcie.c
> new file mode 100644
> index 000000000000..0c5d0732cd1c
> --- /dev/null
> +++ b/drivers/phy/amlogic/phy-meson-axg-pcie.c
> @@ -0,0 +1,192 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Amlogic AXG PCIE PHY driver
> + *
> + * Copyright (C) 2020 Remi Pommarel <repk@xxxxxxxxxxxx>
> + */
> +#include <linux/module.h>
> +#include <linux/phy/phy.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/platform_device.h>
> +#include <linux/bitfield.h>
> +#include <dt-bindings/phy/phy.h>
> +
> +#define MESON_PCIE_REG0 0x00
> +#define MESON_PCIE_COMMON_CLK BIT(4)
> +#define MESON_PCIE_PORT_SEL GENMASK(3, 2)
> +#define MESON_PCIE_CLK BIT(1)
> +#define MESON_PCIE_POWERDOWN BIT(0)
> +
> +#define MESON_PCIE_TWO_X1 FIELD_PREP(MESON_PCIE_PORT_SEL, 0x3)
> +#define MESON_PCIE_COMMON_REF_CLK FIELD_PREP(MESON_PCIE_COMMON_CLK, 0x1)
> +#define MESON_PCIE_PHY_INIT (MESON_PCIE_TWO_X1 | \
> + MESON_PCIE_COMMON_REF_CLK)
> +#define MESON_PCIE_RESET_DELAY 500
> +
> +struct phy_axg_pcie_priv {
> + struct phy *phy;
> + struct phy *analog;
> + struct regmap *regmap;
> + struct reset_control *reset;
> +};
> +
> +static const struct regmap_config phy_axg_pcie_regmap_conf = {
> + .reg_bits = 8,
> + .val_bits = 32,
> + .reg_stride = 4,
> + .max_register = MESON_PCIE_REG0,
> +};
> +
> +static int phy_axg_pcie_power_on(struct phy *phy)
> +{
> + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
> + int ret;
> +
> + ret = phy_power_on(priv->analog);
> + if (ret != 0)
> + return ret;
> +
> + regmap_update_bits(priv->regmap, MESON_PCIE_REG0,
> + MESON_PCIE_POWERDOWN, 0);
> + return 0;
> +}
> +
> +static int phy_axg_pcie_power_off(struct phy *phy)
> +{
> + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
> + int ret;
> +
> + ret = phy_power_off(priv->analog);
> + if (ret != 0)
> + return ret;
> +
> + regmap_update_bits(priv->regmap, MESON_PCIE_REG0,
> + MESON_PCIE_POWERDOWN, 1);
> + return 0;
> +}
> +
> +static int phy_axg_pcie_init(struct phy *phy)
> +{
> + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
> + int ret;
> +
> + ret = phy_init(priv->analog);
> + if (ret != 0)
> + return ret;
> +
> + regmap_write(priv->regmap, MESON_PCIE_REG0, MESON_PCIE_PHY_INIT);
> + return reset_control_reset(priv->reset);
> +}
> +
> +static int phy_axg_pcie_exit(struct phy *phy)
> +{
> + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
> + int ret;
> +
> + ret = phy_exit(priv->analog);
> + if (ret != 0)
> + return ret;
> +
> + return reset_control_reset(priv->reset);
> +}
> +
> +static int phy_axg_pcie_reset(struct phy *phy)
> +{
> + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
> + int ret = 0;
> +
> + ret = phy_reset(priv->analog);
> + if (ret != 0)
> + goto out;
> +
> + ret = reset_control_assert(priv->reset);
> + if (ret != 0)
> + goto out;
> + udelay(MESON_PCIE_RESET_DELAY);
> +
> + ret = reset_control_deassert(priv->reset);
> + if (ret != 0)
> + goto out;
> + udelay(MESON_PCIE_RESET_DELAY);
> +
> +out:
> + return ret;
> +}
> +
> +static const struct phy_ops phy_axg_pcie_ops = {
> + .init = phy_axg_pcie_init,
> + .exit = phy_axg_pcie_exit,
> + .power_on = phy_axg_pcie_power_on,
> + .power_off = phy_axg_pcie_power_off,
> + .reset = phy_axg_pcie_reset,
> + .owner = THIS_MODULE,
> +};
> +
> +static int phy_axg_pcie_probe(struct platform_device *pdev)
> +{
> + struct phy_provider *pphy;
> + struct device *dev = &pdev->dev;
> + struct phy_axg_pcie_priv *priv;
> + struct device_node *np = dev->of_node;
> + struct resource *res;
> + void __iomem *base;
> + int ret;
> +
> + priv = devm_kmalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->phy = devm_phy_create(dev, np, &phy_axg_pcie_ops);
> + if (IS_ERR(priv->phy)) {
> + ret = PTR_ERR(priv->phy);
> + if (ret != -EPROBE_DEFER)
> + dev_err(dev, "failed to create PHY\n");
> + return ret;
> + }
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + priv->regmap = devm_regmap_init_mmio(dev, base,
> + &phy_axg_pcie_regmap_conf);
> + if (IS_ERR(priv->regmap))
> + return PTR_ERR(priv->regmap);
> +
> + priv->reset = devm_reset_control_array_get(dev, false, false);
> + if (IS_ERR(priv->reset))
> + return PTR_ERR(priv->reset);
> +
> + priv->analog = devm_phy_optional_get(dev, "analog");
> + if (IS_ERR(priv->analog))
> + return PTR_ERR(priv->analog);
Isn't required for on the axg platform for the pcie to work reliably ?
Does this driver support another SoC ?
> +
> + phy_set_drvdata(priv->phy, priv);
> + dev_set_drvdata(dev, priv);
> + pphy = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +
> + return PTR_ERR_OR_ZERO(pphy);
> +}
> +
> +static const struct of_device_id phy_axg_pcie_of_match[] = {
> + {
> + .compatible = "amlogic,axg-pcie-phy",
> + },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, phy_axg_pcie_of_match);
> +
> +static struct platform_driver phy_axg_pcie_driver = {
> + .probe = phy_axg_pcie_probe,
> + .driver = {
> + .name = "phy-axg-pcie",
> + .of_match_table = phy_axg_pcie_of_match,
> + },
> +};
> +module_platform_driver(phy_axg_pcie_driver);
> +
> +MODULE_AUTHOR("Remi Pommarel <repk@xxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Amlogic AXG PCIE PHY driver");
> +MODULE_LICENSE("GPL v2");
