Commit a80d8fb7 authored by Oleksij Rempel's avatar Oleksij Rempel Committed by Jakub Kicinski
Browse files

net: phy: dp83td510: add SQI support 



Convert MSE (mean-square error) values to SNR and split it SQI (Signal Quality
Indicator) ranges. The used ranges are taken from "OPEN ALLIANCE - Advanced
diagnostic features for 100BASE-T1 automotive Ethernet PHYs"
specification.

Signed-off-by: default avatarOleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20220620115601.2035452-1-o.rempel@pengutronix.de


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent b1f01b4b

drivers/net/phy/dp83td510.c

+49 −0
Original line number Diff line number Diff line
@@ -27,6 +27,27 @@ 
#define DP83TD510E_AN_STAT_1			0x60c

#define DP83TD510E_MASTER_SLAVE_RESOL_FAIL	BIT(15)



#define DP83TD510E_MSE_DETECT			0xa85



#define DP83TD510_SQI_MAX	7



/* Register values are converted to SNR(dB) as suggested by

 * "Application Report - DP83TD510E Cable Diagnostics Toolkit":

 * SNR(dB) = -10 * log10 (VAL/2^17) - 1.76 dB.

 * SQI ranges are implemented according to "OPEN ALLIANCE - Advanced diagnostic

 * features for 100BASE-T1 automotive Ethernet PHYs"

 */

static const u16 dp83td510_mse_sqi_map[] = {

	0x0569, /* < 18dB */

	0x044c, /* 18dB =< SNR < 19dB */

	0x0369, /* 19dB =< SNR < 20dB */

	0x02b6, /* 20dB =< SNR < 21dB */

	0x0227, /* 21dB =< SNR < 22dB */

	0x01b6, /* 22dB =< SNR < 23dB */

	0x015b, /* 23dB =< SNR < 24dB */

	0x0000  /* 24dB =< SNR */

};



static int dp83td510_config_intr(struct phy_device *phydev)

{

	int ret;
@@ -164,6 +185,32 @@ static int dp83td510_config_aneg(struct phy_device *phydev) 
	return genphy_c45_check_and_restart_aneg(phydev, changed);

}



static int dp83td510_get_sqi(struct phy_device *phydev)

{

	int sqi, ret;

	u16 mse_val;



	if (!phydev->link)

		return 0;



	ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TD510E_MSE_DETECT);

	if (ret < 0)

		return ret;



	mse_val = 0xFFFF & ret;

	for (sqi = 0; sqi < ARRAY_SIZE(dp83td510_mse_sqi_map); sqi++) {

		if (mse_val >= dp83td510_mse_sqi_map[sqi])

			return sqi;

	}



	return -EINVAL;

}



static int dp83td510_get_sqi_max(struct phy_device *phydev)

{

	return DP83TD510_SQI_MAX;

}



static int dp83td510_get_features(struct phy_device *phydev)

{

	/* This PHY can't respond on MDIO bus if no RMII clock is enabled.
@@ -192,6 +239,8 @@ static struct phy_driver dp83td510_driver[] = { 
	.get_features	= dp83td510_get_features,

	.config_intr	= dp83td510_config_intr,

	.handle_interrupt = dp83td510_handle_interrupt,

	.get_sqi	= dp83td510_get_sqi,

	.get_sqi_max	= dp83td510_get_sqi_max,



	.suspend	= genphy_suspend,

	.resume		= genphy_resume,