Commit 63c85ad0 authored by Li Jun's avatar Li Jun Committed by Vinod Koul
Browse files

phy: fsl-imx8mp-usb: add support for phy tuning 



Add USB PHY parameter tuning for USB certifications.

Reviewed-by: default avatarHaibo Chen <haibo.chen@nxp.com>
Signed-off-by: default avatarLi Jun <jun.li@nxp.com>
[j.zink: ported to v6.3-rc1 from NXP downstream repo + cleanups]
Signed-off-by: default avatarJohannes Zink <j.zink@pengutronix.de>
Link: https://lore.kernel.org/r/20230516-lustige-usb-phy-dinge-v2-2-3383a0de34ac@pengutronix.de


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent b2e75563

drivers/phy/freescale/phy-fsl-imx8mq-usb.c

+218 −0
Original line number Diff line number Diff line
@@ -27,17 +27,231 @@ 
#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_TXRISE_TUNE_MASK	GENMASK(21, 20)

#define PHY_CTRL3_TXVREF_TUNE_MASK	GENMASK(25, 22)

#define PHY_CTRL3_TX_VBOOST_LEVEL_MASK	GENMASK(31, 29)



#define PHY_CTRL4			0x10

#define PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_MASK	GENMASK(20, 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_ALT_CLK_EN		BIT(1)

#define PHY_CTRL6_ALT_CLK_SEL		BIT(0)



#define PHY_TUNE_DEFAULT		0xffffffff



struct imx8mq_usb_phy {

	struct phy *phy;

	struct clk *clk;

	void __iomem *base;

	struct regulator *vbus;

	u32 pcs_tx_swing_full;

	u32 pcs_tx_deemph_3p5db;

	u32 tx_vref_tune;

	u32 tx_rise_tune;

	u32 tx_preemp_amp_tune;

	u32 tx_vboost_level;

	u32 comp_dis_tune;

};



static u32 phy_tx_vref_tune_from_property(u32 percent)

{

	percent = clamp(percent, 94U, 124U);



	return DIV_ROUND_CLOSEST(percent - 94U, 2);

}



static u32 phy_tx_rise_tune_from_property(u32 percent)

{

	switch (percent) {

	case 0 ... 98:

		return 3;

	case 99:

		return 2;

	case 100 ... 101:

		return 1;

	default:

		return 0;

	}

}



static u32 phy_tx_preemp_amp_tune_from_property(u32 microamp)

{

	microamp = min(microamp, 1800U);



	return microamp / 600;

}



static u32 phy_tx_vboost_level_from_property(u32 microvolt)

{

	switch (microvolt) {

	case 0 ... 960:

		return 0;

	case 961 ... 1160:

		return 2;

	default:

		return 3;

	}

}



static u32 phy_pcs_tx_deemph_3p5db_from_property(u32 decibel)

{

	return min(decibel, 36U);

}



static u32 phy_comp_dis_tune_from_property(u32 percent)

{

	switch (percent) {

	case 0 ... 92:

		return 0;

	case 93 ... 95:

		return 1;

	case 96 ... 97:

		return 2;

	case 98 ... 102:

		return 3;

	case 103 ... 105:

		return 4;

	case 106 ... 109:

		return 5;

	case 110 ... 113:

		return 6;

	default:

		return 7;

	}

}

static u32 phy_pcs_tx_swing_full_from_property(u32 percent)

{

	percent = min(percent, 100U);



	return (percent * 127) / 100;

}



static void imx8m_get_phy_tuning_data(struct imx8mq_usb_phy *imx_phy)

{

	struct device *dev = imx_phy->phy->dev.parent;



	if (device_property_read_u32(dev, "fsl,phy-tx-vref-tune-percent",

				     &imx_phy->tx_vref_tune))

		imx_phy->tx_vref_tune = PHY_TUNE_DEFAULT;

	else

		imx_phy->tx_vref_tune =

			phy_tx_vref_tune_from_property(imx_phy->tx_vref_tune);



	if (device_property_read_u32(dev, "fsl,phy-tx-rise-tune-percent",

				     &imx_phy->tx_rise_tune))

		imx_phy->tx_rise_tune = PHY_TUNE_DEFAULT;

	else

		imx_phy->tx_rise_tune =

			phy_tx_rise_tune_from_property(imx_phy->tx_rise_tune);



	if (device_property_read_u32(dev, "fsl,phy-tx-preemp-amp-tune-microamp",

				     &imx_phy->tx_preemp_amp_tune))

		imx_phy->tx_preemp_amp_tune = PHY_TUNE_DEFAULT;

	else

		imx_phy->tx_preemp_amp_tune =

			phy_tx_preemp_amp_tune_from_property(imx_phy->tx_preemp_amp_tune);



	if (device_property_read_u32(dev, "fsl,phy-tx-vboost-level-microvolt",

				     &imx_phy->tx_vboost_level))

		imx_phy->tx_vboost_level = PHY_TUNE_DEFAULT;

	else

		imx_phy->tx_vboost_level =

			phy_tx_vboost_level_from_property(imx_phy->tx_vboost_level);



	if (device_property_read_u32(dev, "fsl,phy-comp-dis-tune-percent",

				     &imx_phy->comp_dis_tune))

		imx_phy->comp_dis_tune = PHY_TUNE_DEFAULT;

	else

		imx_phy->comp_dis_tune =

			phy_comp_dis_tune_from_property(imx_phy->comp_dis_tune);



	if (device_property_read_u32(dev, "fsl,pcs-tx-deemph-3p5db-attenuation-db",

				     &imx_phy->pcs_tx_deemph_3p5db))

		imx_phy->pcs_tx_deemph_3p5db = PHY_TUNE_DEFAULT;

	else

		imx_phy->pcs_tx_deemph_3p5db =

			phy_pcs_tx_deemph_3p5db_from_property(imx_phy->pcs_tx_deemph_3p5db);



	if (device_property_read_u32(dev, "fsl,phy-pcs-tx-swing-full-percent",

				     &imx_phy->pcs_tx_swing_full))

		imx_phy->pcs_tx_swing_full = PHY_TUNE_DEFAULT;

	else

		imx_phy->pcs_tx_swing_full =

			phy_pcs_tx_swing_full_from_property(imx_phy->pcs_tx_swing_full);

}



static void imx8m_phy_tune(struct imx8mq_usb_phy *imx_phy)

{

	u32 value;



	/* PHY tuning */

	if (imx_phy->pcs_tx_deemph_3p5db != PHY_TUNE_DEFAULT) {

		value = readl(imx_phy->base + PHY_CTRL4);

		value &= ~PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_MASK;

		value |= FIELD_PREP(PHY_CTRL4_PCS_TX_DEEMPH_3P5DB_MASK,

				   imx_phy->pcs_tx_deemph_3p5db);

		writel(value, imx_phy->base + PHY_CTRL4);

	}



	if (imx_phy->pcs_tx_swing_full != PHY_TUNE_DEFAULT) {

		value = readl(imx_phy->base + PHY_CTRL5);

		value |= FIELD_PREP(PHY_CTRL5_PCS_TX_SWING_FULL_MASK,

				   imx_phy->pcs_tx_swing_full);

		writel(value, imx_phy->base + PHY_CTRL5);

	}



	if ((imx_phy->tx_vref_tune & imx_phy->tx_rise_tune &

	     imx_phy->tx_preemp_amp_tune & imx_phy->comp_dis_tune &

	     imx_phy->tx_vboost_level) == PHY_TUNE_DEFAULT)

		/* If all are the default values, no need update. */

		return;



	value = readl(imx_phy->base + PHY_CTRL3);



	if (imx_phy->tx_vref_tune != PHY_TUNE_DEFAULT) {

		value &= ~PHY_CTRL3_TXVREF_TUNE_MASK;

		value |= FIELD_PREP(PHY_CTRL3_TXVREF_TUNE_MASK,

				   imx_phy->tx_vref_tune);

	}



	if (imx_phy->tx_rise_tune != PHY_TUNE_DEFAULT) {

		value &= ~PHY_CTRL3_TXRISE_TUNE_MASK;

		value |= FIELD_PREP(PHY_CTRL3_TXRISE_TUNE_MASK,

				    imx_phy->tx_rise_tune);

	}



	if (imx_phy->tx_preemp_amp_tune != PHY_TUNE_DEFAULT) {

		value &= ~PHY_CTRL3_TXPREEMP_TUNE_MASK;

		value |= FIELD_PREP(PHY_CTRL3_TXPREEMP_TUNE_MASK,

				imx_phy->tx_preemp_amp_tune);

	}



	if (imx_phy->comp_dis_tune != PHY_TUNE_DEFAULT) {

		value &= ~PHY_CTRL3_COMPDISTUNE_MASK;

		value |= FIELD_PREP(PHY_CTRL3_COMPDISTUNE_MASK,

				    imx_phy->comp_dis_tune);

	}



	if (imx_phy->tx_vboost_level != PHY_TUNE_DEFAULT) {

		value &= ~PHY_CTRL3_TX_VBOOST_LEVEL_MASK;

		value |= FIELD_PREP(PHY_CTRL3_TX_VBOOST_LEVEL_MASK,

				    imx_phy->tx_vboost_level);

	}



	writel(value, imx_phy->base + PHY_CTRL3);

}



static int imx8mq_usb_phy_init(struct phy *phy)

{

	struct imx8mq_usb_phy *imx_phy = phy_get_drvdata(phy);
@@ -99,6 +313,8 @@ static int imx8mp_usb_phy_init(struct phy *phy) 
	value &= ~(PHY_CTRL1_RESET | PHY_CTRL1_ATERESET);

	writel(value, imx_phy->base + PHY_CTRL1);



	imx8m_phy_tune(imx_phy);



	return 0;

}
@@ -182,6 +398,8 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev) 


	phy_set_drvdata(imx_phy->phy, imx_phy);



	imx8m_get_phy_tuning_data(imx_phy);



	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);



	return PTR_ERR_OR_ZERO(phy_provider);