[PATCH v2 2/3] phy: amlogic: Add Amlogic AXG PCIE PHY Driver

Remi Pommarel
2019-12-23T21:38:15Z

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.

Signed-off-by: Remi Pommarel <repk@triplefau.lt>
---
drivers/phy/amlogic/Kconfig | 11 ++
drivers/phy/amlogic/Makefile | 1 +
drivers/phy/amlogic/phy-meson-axg-pcie.c | 163 +++++++++++++++++++++++
3 files changed, 175 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 1eeb75d018e3..2a3935169ef4 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
tristate "Meson AXG MIPI + PCIE PHY driver"
default ARCH_MESON
diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
index 2167330a0ae8..5fd3a6dca0a5 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) += phy-meson-axg-mipi-pcie.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..559c42c1524d
--- /dev/null
+++ b/drivers/phy/amlogic/phy-meson-axg-pcie.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Amlogic AXG PCIE PHY driver
+ *
+ * Copyright (C) 2019 Remi Pommarel <repk@triplefau.lt>
+ */
+#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 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);
+
+ 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);
+
+ 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);
+
+ 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);
+
+ 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 = 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);
+
+ 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@triplefau.lt>");
+MODULE_DESCRIPTION("Amlogic AXG PCIE PHY driver");
+MODULE_LICENSE("GPL v2");
--
2.24.0