[PATCH v2 1/2] phy: add PCIe PHY driver for mt7623 SoCs families

[Ryder Lee]

support PCIe PHY of MT7623 SoCs families

Signed-off-by: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
---
 drivers/phy/Kconfig           |   8 ++
 drivers/phy/Makefile          |   1 +
 drivers/phy/phy-mt7623-pcie.c | 290 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 299 insertions(+)
 create mode 100644 drivers/phy/phy-mt7623-pcie.c

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index afaf7b6..94b3e61 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -530,4 +530,12 @@ config PHY_MESON8B_USB2
 	  and GXBB SoCs.
 	  If unsure, say N.
 
+config PHY_MT7623_PCIE
+	tristate "Mediatek PCIe PHY driver for MT7623 SoC families"
+	depends on ARCH_MEDIATEK && OF
+	select GENERIC_PHY
+	select MFD_SYSCON
+	help
+	  Say 'Y' here to add support for Mediatek PCIe PHY driver which
+	  can be found on the MT7623 SoC families.
 endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index f8047b4..0185f6a 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -64,3 +64,4 @@ obj-$(CONFIG_PHY_CYGNUS_PCIE)		+= phy-bcm-cygnus-pcie.o
 obj-$(CONFIG_ARCH_TEGRA) += tegra/
 obj-$(CONFIG_PHY_NS2_PCIE)		+= phy-bcm-ns2-pcie.o
 obj-$(CONFIG_PHY_MESON8B_USB2)		+= phy-meson8b-usb2.o
+obj-$(CONFIG_PHY_MT7623_PCIE)		+= phy-mt7623-pcie.o
diff --git a/drivers/phy/phy-mt7623-pcie.c b/drivers/phy/phy-mt7623-pcie.c
new file mode 100644
index 0000000..9c32601
--- /dev/null
+++ b/drivers/phy/phy-mt7623-pcie.c
@@ -0,0 +1,290 @@
+/*
+ * Copyright (c) 2017 MediaTek Inc.
+ * Author: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* Offsets of sub-segment in each port registers */
+#define PCIE_SIFSLV_PHYD_BANK2_BASE	0xa00
+#define SSUSB_SIFSLV_PHYA_BASE		0xb00
+#define SSUSB_SIFSLV_PHYA_DA_BASE	0xc00
+
+/*
+ * RX detection stable - 1 scale represent 8 reference cycles
+ * cover reference clock from 1M~100MHz, 7us~40us
+ */
+#define B2_PHYD_RXDET1			(PCIE_SIFSLV_PHYD_BANK2_BASE + 0x28)
+#define RG_SSUSB_RXDET_STB2		GENMASK(17, 9)
+#define RG_SSUSB_RXDET_STB2_VAL(x)	((0x1ff & (x)) << 9)
+
+#define B2_PHYD_RXDET2			(PCIE_SIFSLV_PHYD_BANK2_BASE + 0x2c)
+#define RG_SSUSB_RXDET_STB2_P3		GENMASK(8, 0)
+#define RG_SSUSB_RXDET_STB2_P3_VAL(x)	(0x1ff & (x))
+
+#define U3_PHYA_REG0			(SSUSB_SIFSLV_PHYA_BASE + 0x00)
+#define RG_PCIE_CLKDRV_OFFSET		GENMASK(3, 1)
+#define RG_PCIE_CLKDRV_OFFSET_VAL(x)	((0x3 & (x)) << 2)
+
+#define U3_PHYA_REG1			(SSUSB_SIFSLV_PHYA_BASE + 0x04)
+#define RG_PCIE_CLKDRV_AMP		GENMASK(31, 29)
+#define RG_PCIE_CLKDRV_AMP_VAL(x)	((0x7 & (x)) << 29)
+
+#define DA_SSUSB_CDR_REFCK_SEL		(SSUSB_SIFSLV_PHYA_DA_BASE + 0x00)
+#define RG_SSUSB_XTAL_EXT_PE1H		GENMASK(13, 12)
+#define RG_SSUSB_XTAL_EXT_PE1H_VAL(x)	((0x3 & (x)) << 12)
+#define RG_SSUSB_XTAL_EXT_PE2H		GENMASK(17, 16)
+#define RG_SSUSB_XTAL_EXT_PE2H_VAL(x)		((0x3 & (x)) << 16)
+
+#define DA_SSUSB_PLL_IC			(SSUSB_SIFSLV_PHYA_DA_BASE + 0x0c)
+#define RG_SSUSB_PLL_IC_PE2H		GENMASK(15, 12)
+#define RG_SSUSB_PLL_IC_PE2H_VAL(x)	((0xf & (x)) << 12)
+#define RG_SSUSB_PLL_BR_PE2H		GENMASK(29, 28)
+#define RG_SSUSB_PLL_BR_PE2H_VAL(x)	((0x3 & (x)) << 28)
+
+#define DA_SSUSB_PLL_BC			(SSUSB_SIFSLV_PHYA_DA_BASE + 0x08)
+#define RG_SSUSB_PLL_DIVEN_PE2H		GENMASK(21, 19)
+#define RG_SSUSB_PLL_BC_PE2H		GENMASK(7, 6)
+#define RG_SSUSB_PLL_BC_PE2H_VAL(x)	((0x3 & (x)) << 6)
+
+#define DA_SSUSB_PLL_IR			(SSUSB_SIFSLV_PHYA_DA_BASE + 0x10)
+#define RG_SSUSB_PLL_IR_PE2H		GENMASK(19, 16)
+#define RG_SSUSB_PLL_IR_PE2H_VAL(x)	((0xf & (x)) << 16)
+
+#define DA_SSUSB_PLL_BP			(SSUSB_SIFSLV_PHYA_DA_BASE + 0x14)
+#define RG_SSUSB_PLL_BP_PE2H		GENMASK(19, 16)
+#define RG_SSUSB_PLL_BP_PE2H_VAL(x)	((0xf & (x)) << 16)
+
+#define DA_SSUSB_PLL_SSC_DELTA1_REG20	(SSUSB_SIFSLV_PHYA_DA_BASE + 0x3c)
+#define RG_SSUSB_PLL_SSC_DELTA1_PE2H		GENMASK(31, 16)
+#define RG_SSUSB_PLL_SSC_DELTA1_PE2H_VAL(x)	((0xffff & (x)) << 16)
+
+#define DA_SSUSB_PLL_SSC_DELTA_REG25	(SSUSB_SIFSLV_PHYA_DA_BASE + 0x48)
+#define RG_SSUSB_PLL_SSC_DELTA_PE2H		GENMASK(15, 0)
+#define RG_SSUSB_PLL_SSC_DELTA_PE2H_VAL(x)	(0xffff & (x))
+
+#define HIF_SYSCFG1			0x14
+#define HIF_SYSCFG1_PHY2_MASK		(0x3 << 20)
+
+struct mtk_pcie_phy {
+	struct device *dev;
+	void __iomem *base;
+	struct regmap *hif;
+	struct clk *phya_ref;
+	struct phy *phy;
+};
+
+static inline u32 phy_read(struct mtk_pcie_phy *phy, u32 reg)
+{
+	return readl(phy->base + reg);
+}
+
+static inline void phy_write(struct mtk_pcie_phy *phy, u32 val, u32 reg)
+{
+	writel(val, phy->base + reg);
+}
+
+static int mtk_pcie_phy_power_on(struct phy *phy)
+{
+	struct mtk_pcie_phy *mtk_phy = phy_get_drvdata(phy);
+	int err;
+	u32 val;
+
+	/* enable PCIe mode */
+	if (mtk_phy->hif)
+		regmap_update_bits(mtk_phy->hif, HIF_SYSCFG1,
+				   HIF_SYSCFG1_PHY2_MASK, 0);
+
+	err = clk_prepare_enable(mtk_phy->phya_ref);
+	if (err) {
+		dev_err(mtk_phy->dev, "failed to enable PCIe phy clock\n");
+		return err;
+	}
+
+	val = phy_read(mtk_phy, DA_SSUSB_CDR_REFCK_SEL);
+	val &= ~(RG_SSUSB_XTAL_EXT_PE1H | RG_SSUSB_XTAL_EXT_PE2H);
+	val |= RG_SSUSB_XTAL_EXT_PE1H_VAL(0x2) |
+	       RG_SSUSB_XTAL_EXT_PE2H_VAL(0x2);
+	phy_write(mtk_phy, val, DA_SSUSB_CDR_REFCK_SEL);
+
+	/* ref clk drive */
+	val = phy_read(mtk_phy, U3_PHYA_REG1);
+	val &= ~RG_PCIE_CLKDRV_AMP;
+	val |= RG_PCIE_CLKDRV_AMP_VAL(0x4);
+	phy_write(mtk_phy, val, U3_PHYA_REG1);
+
+	val = phy_read(mtk_phy, U3_PHYA_REG0);
+	val &= ~RG_PCIE_CLKDRV_OFFSET;
+	val |= RG_PCIE_CLKDRV_OFFSET_VAL(0x1);
+	phy_write(mtk_phy, val, U3_PHYA_REG0);
+
+	/* SSC delta -5000ppm */
+	val = phy_read(mtk_phy, DA_SSUSB_PLL_SSC_DELTA1_REG20);
+	val &= ~RG_SSUSB_PLL_SSC_DELTA1_PE2H;
+	val |= RG_SSUSB_PLL_SSC_DELTA1_PE2H_VAL(0x3c);
+	phy_write(mtk_phy, val, DA_SSUSB_PLL_SSC_DELTA1_REG20);
+
+	val = phy_read(mtk_phy, DA_SSUSB_PLL_SSC_DELTA_REG25);
+	val &= ~RG_SSUSB_PLL_SSC_DELTA_PE2H;
+	val |= RG_SSUSB_PLL_SSC_DELTA_PE2H_VAL(0x36);
+	phy_write(mtk_phy, val, DA_SSUSB_PLL_SSC_DELTA_REG25);
+
+	/* change pll BW 0.6M */
+	val = phy_read(mtk_phy, DA_SSUSB_PLL_IC);
+	val &= ~RG_SSUSB_PLL_BR_PE2H;
+	val |= RG_SSUSB_PLL_BR_PE2H_VAL(0x1);
+	phy_write(mtk_phy, val, DA_SSUSB_PLL_IC);
+
+	val = phy_read(mtk_phy, DA_SSUSB_PLL_BC);
+	val &= ~(RG_SSUSB_PLL_DIVEN_PE2H | RG_SSUSB_PLL_BC_PE2H);
+	val |= RG_SSUSB_PLL_BC_PE2H_VAL(0x3);
+	phy_write(mtk_phy, val, DA_SSUSB_PLL_BC);
+
+	val = phy_read(mtk_phy, DA_SSUSB_PLL_IR);
+	val &= ~RG_SSUSB_PLL_IR_PE2H;
+	val |= RG_SSUSB_PLL_IR_PE2H_VAL(0x2);
+	phy_write(mtk_phy, val, DA_SSUSB_PLL_IR);
+
+	val = phy_read(mtk_phy, DA_SSUSB_PLL_IC);
+	val &= ~RG_SSUSB_PLL_IC_PE2H;
+	val |= RG_SSUSB_PLL_IC_PE2H_VAL(0x1);
+	phy_write(mtk_phy, val, DA_SSUSB_PLL_IC);
+
+	val = phy_read(mtk_phy, DA_SSUSB_PLL_BP);
+	val &= ~RG_SSUSB_PLL_BP_PE2H;
+	val |= RG_SSUSB_PLL_BP_PE2H_VAL(0xa);
+	phy_write(mtk_phy, val, DA_SSUSB_PLL_BP);
+
+	/* Tx Detect Rx Timing: 10us -> 5us */
+	val = phy_read(mtk_phy, B2_PHYD_RXDET1);
+	val &= ~RG_SSUSB_RXDET_STB2;
+	val |= RG_SSUSB_RXDET_STB2_VAL(0x10);
+	phy_write(mtk_phy, val, B2_PHYD_RXDET1);
+
+	val = phy_read(mtk_phy, B2_PHYD_RXDET2);
+	val &= ~RG_SSUSB_RXDET_STB2_P3;
+	val |= RG_SSUSB_RXDET_STB2_P3_VAL(0x10);
+	phy_write(mtk_phy, val, B2_PHYD_RXDET2);
+
+	/* wait for PCIe subsys register to active */
+	usleep_range(2500, 3000);
+
+	return 0;
+}
+
+static int mtk_pcie_phy_power_off(struct phy *phy)
+{
+	struct mtk_pcie_phy *mtk_phy = phy_get_drvdata(phy);
+
+	clk_disable_unprepare(mtk_phy->phya_ref);
+
+	return 0;
+}
+
+static struct phy_ops mtk_pcie_phy_ops = {
+	.power_on	= mtk_pcie_phy_power_on,
+	.power_off	= mtk_pcie_phy_power_off,
+	.owner		= THIS_MODULE,
+};
+
+static const struct of_device_id mtk_pcie_phy_of_match[];
+
+static int mtk_pcie_phy_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	const struct of_device_id *match;
+	struct phy_provider *phy_provider;
+	struct mtk_pcie_phy *mtk_phy;
+	struct resource *res;
+	struct phy *phy;
+
+	match = of_match_device(mtk_pcie_phy_of_match, &pdev->dev);
+	if (!match)
+		return -ENODEV;
+
+	mtk_phy = devm_kzalloc(&pdev->dev, sizeof(*mtk_phy), GFP_KERNEL);
+	if (!mtk_phy)
+		return -ENOMEM;
+
+	mtk_phy->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mtk_phy->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mtk_phy->base)) {
+		dev_err(&pdev->dev, "failed to get phy base\n");
+		return PTR_ERR(mtk_phy->base);
+	}
+
+	mtk_phy->phya_ref = devm_clk_get(&pdev->dev, "pciephya_ref");
+	if (IS_ERR(mtk_phy->phya_ref)) {
+		dev_err(&pdev->dev, "error to get pciephya_ref\n");
+		return PTR_ERR(mtk_phy->phya_ref);
+	}
+
+	if (of_find_property(np, "mediatek,phy-switch", NULL)) {
+		mtk_phy->hif = syscon_regmap_lookup_by_phandle(
+						np, "mediatek,phy-switch");
+		if (IS_ERR(mtk_phy->hif)) {
+			dev_err(&pdev->dev, "missing \"mediatek,phy-switch\" phandle\n");
+			return PTR_ERR(mtk_phy->hif);
+		}
+	}
+
+	platform_set_drvdata(pdev, mtk_phy);
+	phy = devm_phy_create(&pdev->dev, NULL, &mtk_pcie_phy_ops);
+	if (IS_ERR(phy)) {
+		dev_err(&pdev->dev, "failed to create phy device\n");
+		return PTR_ERR(phy);
+	}
+
+	mtk_phy->phy = phy;
+	phy_set_drvdata(phy, mtk_phy);
+
+	phy_provider = devm_of_phy_provider_register(&pdev->dev,
+						     of_phy_simple_xlate);
+	if (IS_ERR(phy_provider)) {
+		dev_err(&pdev->dev, "failed to register phy provider\n");
+		return PTR_ERR(phy_provider);
+	}
+
+	return 0;
+}
+
+static const struct of_device_id mtk_pcie_phy_of_match[] = {
+	{ .compatible = "mediatek,mt7623-pcie-phy"},
+	{ .compatible = "mediatek,mt2701-pcie-phy"},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mtk_pcie_phy_of_match);
+
+static struct platform_driver mtk_pcie_phy_driver = {
+	.probe	= mtk_pcie_phy_probe,
+	.driver = {
+		.name	= "mtk-pcie-phy",
+		.of_match_table	= mtk_pcie_phy_of_match,
+	}
+};
+module_platform_driver(mtk_pcie_phy_driver);
+
+MODULE_AUTHOR("Ryder Lee <ryder.lee@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Mediatek PCIe PHY driver");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1