[PATCH v6 3/8] phy: starfive: Add Starfive JH7110 PCIe 2.0 PHY driver

[Minda Chen <minda.chen@starfivetech.com>]

Add Starfive JH7110 PCIe 2.0 PHY driver, which is generic
PHY driver and can be used as USB 3.0 driver.

Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
---
 drivers/phy/starfive/Kconfig           |   7 +
 drivers/phy/starfive/Makefile          |   1 +
 drivers/phy/starfive/phy-jh7110-pcie.c | 239 +++++++++++++++++++++++++
 3 files changed, 247 insertions(+)
 create mode 100644 drivers/phy/starfive/phy-jh7110-pcie.c

diff --git a/drivers/phy/starfive/Kconfig b/drivers/phy/starfive/Kconfig
index a7cf0a55dff..d11338ed484 100644
--- a/drivers/phy/starfive/Kconfig
+++ b/drivers/phy/starfive/Kconfig
@@ -4,6 +4,13 @@
 
 menu "Starfive PHY driver"
 
+config PHY_STARFIVE_JH7110_PCIE
+	bool "Starfive JH7110 PCIe 2.0 PHY driver"
+	depends on PHY
+	help
+	  Enable this to support the Starfive JH7110 PCIE 2.0/USB 3.0 PHY.
+	  Generic PHY driver JH7110 USB 3.0/ PCIe 2.0.
+
 config PHY_STARFIVE_JH7110_USB2
 	bool "Starfive JH7110 USB 2.0 PHY driver"
 	depends on PHY
diff --git a/drivers/phy/starfive/Makefile b/drivers/phy/starfive/Makefile
index a405a75e34c..82f25aa21b7 100644
--- a/drivers/phy/starfive/Makefile
+++ b/drivers/phy/starfive/Makefile
@@ -3,4 +3,5 @@
 # Copyright (C) 2023 Starfive
 #
 
+obj-$(CONFIG_PHY_STARFIVE_JH7110_PCIE)	+= phy-jh7110-pcie.o
 obj-$(CONFIG_PHY_STARFIVE_JH7110_USB2)	+= phy-jh7110-usb2.o
diff --git a/drivers/phy/starfive/phy-jh7110-pcie.c b/drivers/phy/starfive/phy-jh7110-pcie.c
new file mode 100644
index 00000000000..ecb04bdedfa
--- /dev/null
+++ b/drivers/phy/starfive/phy-jh7110-pcie.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * StarFive JH7110 PCIe 2.0 PHY driver
+ *
+ * Copyright (C) 2024 StarFive Technology Co., Ltd.
+ * Author: Minda Chen <minda.chen@starfivetech.com>
+ */
+#include <asm/io.h>
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <errno.h>
+#include <generic-phy.h>
+#include <regmap.h>
+#include <soc.h>
+#include <syscon.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+
+#include "phy-jh7110-usb-syscon.h"
+
+#define PCIE_KVCO_LEVEL_OFF			0x28
+#define PCIE_USB3_PHY_PLL_CTL_OFF		0x7c
+#define PCIE_USB3_PHY_SS_MODE			BIT(4)
+#define PCIE_KVCO_TUNE_SIGNAL_OFF		0x80
+#define PHY_KVCO_FINE_TUNE_LEVEL		0x91
+#define PHY_KVCO_FINE_TUNE_SIGNALS		0xc
+
+#define PCIE_USB3_PHY_MODE			0x1
+#define PCIE_BUS_WIDTH				0x2
+#define PCIE_USB3_PHY_ENABLE			0x1
+#define PCIE_USB3_PHY_SPLIT			0x1
+
+struct jh7110_pcie_phy {
+	struct phy *phy;
+	struct regmap *stg_syscon;
+	struct regmap *sys_syscon;
+	void __iomem *regs;
+	struct regmap_field *phy_mode;
+	struct regmap_field *bus_width;
+	struct regmap_field *usb3_phy_en;
+	struct regmap_field *usb_split;
+	enum phy_mode mode;
+};
+
+static int phy_pcie_mode_set(struct jh7110_pcie_phy *data, bool usb_mode)
+{
+	unsigned int phy_mode, width, usb3_phy, ss_mode, split;
+
+	/* default is PCIe mode */
+	if (!data->stg_syscon || !data->sys_syscon) {
+		if (usb_mode) {
+			dev_err(data->phy->dev, "doesn't support USB3 mode\n");
+			return -EINVAL;
+		}
+		return 0;
+	}
+
+	if (usb_mode) {
+		phy_mode = PCIE_USB3_PHY_MODE;
+		width = 0;
+		usb3_phy = PCIE_USB3_PHY_ENABLE;
+		ss_mode = PCIE_USB3_PHY_SS_MODE;
+		split = 0;
+	} else {
+		phy_mode = 0;
+		width = PCIE_BUS_WIDTH;
+		usb3_phy = 0;
+		ss_mode = 0;
+		split = PCIE_USB3_PHY_SPLIT;
+	}
+
+	regmap_field_write(data->phy_mode, phy_mode);
+	regmap_field_write(data->bus_width, width);
+	regmap_field_write(data->usb3_phy_en, usb3_phy);
+	clrsetbits_le32(data->regs + PCIE_USB3_PHY_PLL_CTL_OFF,
+			PCIE_USB3_PHY_SS_MODE, ss_mode);
+	regmap_field_write(data->usb_split, split);
+
+	return 0;
+}
+
+static void phy_kvco_gain_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);
+}
+
+static int jh7110_pcie_phy_set_mode(struct phy *phy,
+				    enum phy_mode mode, int submode)
+{
+	struct udevice *dev = phy->dev;
+	struct jh7110_pcie_phy *pcie_phy = dev_get_priv(dev);
+	int ret;
+
+	if (mode == pcie_phy->mode)
+		return 0;
+
+	switch (mode) {
+	case PHY_MODE_USB_HOST:
+	case PHY_MODE_USB_DEVICE:
+	case PHY_MODE_USB_OTG:
+		ret = phy_pcie_mode_set(pcie_phy, 1);
+		if (ret)
+			return ret;
+		break;
+	case PHY_MODE_PCIE:
+		phy_pcie_mode_set(pcie_phy, 0);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	dev_dbg(phy->dev, "Changing PHY mode to %d\n", mode);
+	pcie_phy->mode = mode;
+
+	return 0;
+}
+
+static const struct phy_ops jh7110_pcie_phy_ops = {
+	.set_mode	= jh7110_pcie_phy_set_mode,
+};
+
+static int phy_stg_regfield_init(struct udevice *dev, int mode, int usb3)
+{
+	struct jh7110_pcie_phy *phy = dev_get_priv(dev);
+	struct reg_field phy_mode = REG_FIELD(mode, 20, 21);
+	struct reg_field bus_width = REG_FIELD(usb3, 2, 3);
+	struct reg_field usb3_phy_en = REG_FIELD(usb3, 4, 4);
+
+	phy->phy_mode = devm_regmap_field_alloc(dev, phy->stg_syscon, phy_mode);
+	if (IS_ERR(phy->phy_mode)) {
+		dev_err(dev, "PHY mode reg field init failed\n");
+		return PTR_ERR(phy->phy_mode);
+	}
+
+	phy->bus_width = devm_regmap_field_alloc(dev, phy->stg_syscon, bus_width);
+	if (IS_ERR(phy->bus_width)) {
+		dev_err(dev, "PHY bus width reg field init failed\n");
+		return PTR_ERR(phy->bus_width);
+	}
+
+	phy->usb3_phy_en = devm_regmap_field_alloc(dev, phy->stg_syscon, usb3_phy_en);
+	if (IS_ERR(phy->usb3_phy_en)) {
+		dev_err(dev, "USB3 PHY enable field init failed\n");
+		return PTR_ERR(phy->bus_width);
+	}
+
+	return 0;
+}
+
+static int phy_sys_regfield_init(struct udevice *dev, int split)
+{
+	struct jh7110_pcie_phy *phy = dev_get_priv(dev);
+	struct reg_field usb_split  = REG_FIELD(split, USB_PDRSTN_SPLIT_BIT, USB_PDRSTN_SPLIT_BIT);
+
+	phy->usb_split = devm_regmap_field_alloc(dev, phy->sys_syscon, usb_split);
+	if (IS_ERR(phy->usb_split)) {
+		dev_err(dev, "USB split field init failed\n");
+		return PTR_ERR(phy->usb_split);
+	}
+
+	return 0;
+}
+
+static int starfive_pcie_phy_get_syscon(struct udevice *dev)
+{
+	struct jh7110_pcie_phy *phy = dev_get_priv(dev);
+	struct ofnode_phandle_args sys_phandle, stg_phandle;
+	int ret;
+
+	/* get corresponding syscon phandle */
+	ret = dev_read_phandle_with_args(dev, "starfive,sys-syscon", NULL, 0, 0,
+					 &sys_phandle);
+
+	if (ret < 0) {
+		dev_err(dev, "Can't get sys cfg phandle: %d\n", ret);
+		return ret;
+	}
+
+	ret = dev_read_phandle_with_args(dev, "starfive,stg-syscon", NULL, 2, 0,
+					 &stg_phandle);
+
+	if (ret < 0) {
+		dev_err(dev, "Can't get stg cfg phandle: %d\n", ret);
+		return ret;
+	}
+
+	phy->sys_syscon = syscon_node_to_regmap(sys_phandle.node);
+	/* get syscon register offset */
+	if (!IS_ERR(phy->sys_syscon)) {
+		ret = phy_sys_regfield_init(dev, SYSCON_USB_PDRSTN_REG_OFFSET);
+		if (ret)
+			return ret;
+	} else {
+		phy->sys_syscon = NULL;
+	}
+
+	phy->stg_syscon = syscon_node_to_regmap(stg_phandle.node);
+	if (!IS_ERR(phy->stg_syscon))
+		return phy_stg_regfield_init(dev, stg_phandle.args[0],
+					     stg_phandle.args[1]);
+	else
+		phy->stg_syscon = NULL;
+
+	return 0;
+}
+
+int jh7110_pcie_phy_probe(struct udevice *dev)
+{
+	struct jh7110_pcie_phy *phy = dev_get_priv(dev);
+	int rc;
+
+	phy->regs = dev_read_addr_ptr(dev);
+	if (!phy->regs)
+		return -EINVAL;
+
+	rc = starfive_pcie_phy_get_syscon(dev);
+	if (rc)
+		return rc;
+
+	phy_kvco_gain_set(phy);
+
+	return 0;
+}
+
+static const struct udevice_id jh7110_pcie_phy[] = {
+	{ .compatible = "starfive,jh7110-pcie-phy"},
+	{},
+};
+
+U_BOOT_DRIVER(jh7110_pcie_phy) = {
+	.name = "jh7110_pcie_phy",
+	.id = UCLASS_PHY,
+	.of_match = jh7110_pcie_phy,
+	.probe = jh7110_pcie_phy_probe,
+	.ops = &jh7110_pcie_phy_ops,
+	.priv_auto	= sizeof(struct jh7110_pcie_phy),
+};
-- 
2.17.1