phy: phy-imx8mq-usb: Add USB PHY driver for i.MX8MQ

Add the USB PHY driver for i.MX8MQ to work with DWC3 USB controller.

Signed-off-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Patrick Wildt <patrick@blueri.se>
Tested-by: Patrick Wildt <patrick@blueri.se>

drivers/phy/Kconfig

@@ -268,5 +268,12 @@ config PHY_MTK_TPHY
 	  multi-ports is first version, otherwise is second veriosn,
 	  so you can easily distinguish them by banks layout.
 
+config PHY_IMX8MQ_USB
+	bool "NXP i.MX8MQ USB PHY Driver"
+	depends on PHY
+	depends on IMX8MQ
+	help
+	  Support the USB3.0 PHY in NXP i.MX8MQ SoC
+
 source "drivers/phy/rockchip/Kconfig"
 endmenu

drivers/phy/Makefile

@@ -31,3 +31,4 @@ obj-$(CONFIG_MT7620_USB_PHY) += mt7620-usb-phy.o
 obj-$(CONFIG_MT76X8_USB_PHY) += mt76x8-usb-phy.o
 obj-$(CONFIG_PHY_DA8XX_USB) += phy-da8xx-usb.o
 obj-$(CONFIG_PHY_MTK_TPHY) += phy-mtk-tphy.o
+obj-$(CONFIG_PHY_IMX8MQ_USB) += phy-imx8mq-usb.o

drivers/phy/phy-imx8mq-usb.c

@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 NXP
+ *
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <dm.h>
+#include <errno.h>
+#include <generic-phy.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <clk.h>
+
+#define PHY_CTRL0			0x0
+#define PHY_CTRL0_REF_SSP_EN		BIT(2)
+#define PHY_CTRL0_FSEL_MASK		GENMASK(10, 5)
+#define PHY_CTRL0_FSEL_24M		0x2a
+#define PHY_CTRL0_FSEL_100M		0x27
+#define PHY_CTRL0_SSC_RANGE_MASK	GENMASK(23, 21)
+#define PHY_CTRL0_SSC_RANGE_4003PPM	(0x2 << 21)
+
+#define PHY_CTRL1			0x4
+#define PHY_CTRL1_RESET			BIT(0)
+#define PHY_CTRL1_COMMONONN		BIT(1)
+#define PHY_CTRL1_ATERESET		BIT(3)
+#define PHY_CTRL1_DCDENB		BIT(17)
+#define PHY_CTRL1_CHRGSEL		BIT(18)
+#define PHY_CTRL1_VDATSRCENB0		BIT(19)
+#define PHY_CTRL1_VDATDETENB0		BIT(20)
+
+#define PHY_CTRL2			0x8
+#define PHY_CTRL2_TXENABLEN0		BIT(8)
+#define PHY_CTRL2_OTG_DISABLE		BIT(9)
+
+#define PHY_CTRL3			0xc
+#define PHY_CTRL3_COMPDISTUNE_MASK	GENMASK(2, 0)
+#define PHY_CTRL3_TXPREEMP_TUNE_MASK	GENMASK(16, 15)
+#define PHY_CTRL3_TXPREEMP_TUNE_SHIFT	15
+#define PHY_CTRL3_TXRISE_TUNE_MASK	GENMASK(21, 20)
+#define PHY_CTRL3_TXRISE_TUNE_SHIFT	20
+/* 1111: +24% ... 0000: -6% step: 2% */
+#define PHY_CTRL3_TXVREF_TUNE_MASK	GENMASK(25, 22)
+#define PHY_CTRL3_TXVREF_TUNE_SHIFT	22
+#define PHY_CTRL3_TX_VBOOST_LEVEL_MASK	GENMASK(31, 29)
+#define PHY_CTRL3_TX_VBOOST_LEVEL_SHIFT	29
+
+#define PHY_CTRL4			0x10
+#define PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_MASK	GENMASK(20, 15)
+#define PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_SHIFT	15
+
+#define PHY_CTRL5			0x14
+#define PHY_CTRL5_DMPWD_OVERRIDE_SEL	BIT(23)
+#define PHY_CTRL5_DMPWD_OVERRIDE	BIT(22)
+#define PHY_CTRL5_DPPWD_OVERRIDE_SEL	BIT(21)
+#define PHY_CTRL5_DPPWD_OVERRIDE	BIT(20)
+#define PHY_CTRL5_PCS_TX_SWING_FULL_MASK	GENMASK(6, 0)
+
+#define PHY_CTRL6			0x18
+#define PHY_CTRL6_RXTERM_OVERRIDE_SEL	BIT(29)
+#define PHY_CTRL6_ALT_CLK_EN		BIT(1)
+#define PHY_CTRL6_ALT_CLK_SEL		BIT(0)
+
+#define PHY_STS0			0x40
+#define PHY_STS0_OTGSESSVLD		BIT(7)
+#define PHY_STS0_CHGDET			BIT(4)
+#define PHY_STS0_FSVPLUS		BIT(3)
+#define PHY_STS0_FSVMINUS		BIT(2)
+
+struct imx8mq_usb_phy {
+#if CONFIG_IS_ENABLED(CLK)
+	struct clk phy_clk;
+#endif
+	void __iomem *base;
+};
+
+static const struct udevice_id imx8mq_usb_phy_of_match[] = {
+	{
+		.compatible = "fsl,imx8mq-usb-phy",
+	},
+	{},
+};
+
+static int imx8mq_usb_phy_init(struct phy *usb_phy)
+{
+	struct udevice *dev = usb_phy->dev;
+	struct imx8mq_usb_phy *imx_phy = dev_get_priv(dev);
+	u32 value;
+
+	value = readl(imx_phy->base + PHY_CTRL1);
+	value &= ~(PHY_CTRL1_VDATSRCENB0 | PHY_CTRL1_VDATDETENB0 |
+		   PHY_CTRL1_COMMONONN);
+	value |= PHY_CTRL1_RESET | PHY_CTRL1_ATERESET;
+	writel(value, imx_phy->base + PHY_CTRL1);
+
+	value = readl(imx_phy->base + PHY_CTRL0);
+	value |= PHY_CTRL0_REF_SSP_EN;
+	value &= ~PHY_CTRL0_SSC_RANGE_MASK;
+	value |= PHY_CTRL0_SSC_RANGE_4003PPM;
+	writel(value, imx_phy->base + PHY_CTRL0);
+
+	value = readl(imx_phy->base + PHY_CTRL2);
+	value |= PHY_CTRL2_TXENABLEN0;
+	writel(value, imx_phy->base + PHY_CTRL2);
+
+	value = readl(imx_phy->base + PHY_CTRL1);
+	value &= ~(PHY_CTRL1_RESET | PHY_CTRL1_ATERESET);
+	writel(value, imx_phy->base + PHY_CTRL1);
+
+	return 0;
+}
+
+static int imx8mq_usb_phy_power_on(struct phy *usb_phy)
+{
+	struct udevice *dev = usb_phy->dev;
+	struct imx8mq_usb_phy *imx_phy = dev_get_priv(dev);
+	u32 value;
+
+#if CONFIG_IS_ENABLED(CLK)
+	int ret;
+	ret = clk_enable(&imx_phy->phy_clk);
+	if (ret) {
+		printf("Failed to enable usb phy clock\n");
+		return ret;
+	}
+#endif
+
+	/* Disable rx term override */
+	value = readl(imx_phy->base + PHY_CTRL6);
+	value &= ~PHY_CTRL6_RXTERM_OVERRIDE_SEL;
+	writel(value, imx_phy->base + PHY_CTRL6);
+
+	return 0;
+}
+
+static int imx8mq_usb_phy_power_off(struct phy *usb_phy)
+{
+	struct udevice *dev = usb_phy->dev;
+	struct imx8mq_usb_phy *imx_phy = dev_get_priv(dev);
+	u32 value;
+
+	/* Override rx term to be 0 */
+	value = readl(imx_phy->base + PHY_CTRL6);
+	value |= PHY_CTRL6_RXTERM_OVERRIDE_SEL;
+	writel(value, imx_phy->base + PHY_CTRL6);
+
+#if CONFIG_IS_ENABLED(CLK)
+	clk_disable(&imx_phy->phy_clk);
+#endif
+
+	return 0;
+}
+
+static int imx8mq_usb_phy_exit(struct phy *usb_phy)
+{
+	return imx8mq_usb_phy_power_off(usb_phy);
+}
+
+struct phy_ops imx8mq_usb_phy_ops = {
+	.init = imx8mq_usb_phy_init,
+	.power_on = imx8mq_usb_phy_power_on,
+	.power_off = imx8mq_usb_phy_power_off,
+	.exit = imx8mq_usb_phy_exit,
+};
+
+int imx8mq_usb_phy_probe(struct udevice *dev)
+{
+	struct imx8mq_usb_phy *priv = dev_get_priv(dev);
+
+	priv->base = dev_read_addr_ptr(dev);
+
+	if (!priv->base)
+		return -EINVAL;
+
+#if CONFIG_IS_ENABLED(CLK)
+	int ret;
+
+	/* Assigned clock already set clock */
+	ret = clk_get_by_name(dev, "phy", &priv->phy_clk);
+	if (ret) {
+		printf("Failed to get usb phy clock\n");
+		return ret;
+	}
+#endif
+
+	return 0;
+}
+
+U_BOOT_DRIVER(nxp_imx8mq_usb_phy) = {
+	.name = "nxp_imx8mq_usb_phy",
+	.id = UCLASS_PHY,
+	.of_match = imx8mq_usb_phy_of_match,
+	.probe = imx8mq_usb_phy_probe,
+	.ops = &imx8mq_usb_phy_ops,
+	.priv_auto	= sizeof(struct imx8mq_usb_phy),
+};