u-boot/drivers/phy/phy-imx8mq-usb.c

// 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),
};