Commit c3131bd5 authored by Niklas Söderlund's avatar Niklas Söderlund Committed by Daniel Lezcano
Browse files

thermal: rcar_gen3_thermal: Read calibration from hardware 



In production hardware the calibration values used to convert register
values to temperatures can be read from hardware. While pre-production
hardware still depends on pseudo values hard-coded in the driver.

Add support for reading out calibration values from hardware if it's
fused. The presence of fused calibration is indicated in the THSCP
register.

Signed-off-by: default avatarNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: default avatarKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20211014103816.1939782-3-niklas.soderlund+renesas@ragnatech.se


Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
parent b8aaf141

drivers/thermal/rcar_gen3_thermal.c

+74 −20
Original line number Diff line number Diff line
@@ -34,6 +34,10 @@ 
#define REG_GEN3_THCODE1	0x50

#define REG_GEN3_THCODE2	0x54

#define REG_GEN3_THCODE3	0x58

#define REG_GEN3_PTAT1		0x5c

#define REG_GEN3_PTAT2		0x60

#define REG_GEN3_PTAT3		0x64

#define REG_GEN3_THSCP		0x68



/* IRQ{STR,MSK,EN} bits */

#define IRQ_TEMP1		BIT(0)
@@ -55,6 +59,9 @@ 
#define THCTR_PONM	BIT(6)

#define THCTR_THSST	BIT(0)



/* THSCP bits */

#define THSCP_COR_PARA_VLD	(BIT(15) | BIT(14))



#define CTEMP_MASK	0xFFF



#define MCELSIUS(temp)	((temp) * 1000)
@@ -245,6 +252,64 @@ static const struct soc_device_attribute r8a7795es1[] = { 
	{ /* sentinel */ }

};



static bool rcar_gen3_thermal_read_fuses(struct rcar_gen3_thermal_priv *priv)

{

	unsigned int i;

	u32 thscp;



	/* If fuses are not set, fallback to pseudo values. */

	thscp = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_THSCP);

	if ((thscp & THSCP_COR_PARA_VLD) != THSCP_COR_PARA_VLD) {

		/* Default THCODE values in case FUSEs are not set. */

		static const int thcodes[TSC_MAX_NUM][3] = {

			{ 3397, 2800, 2221 },

			{ 3393, 2795, 2216 },

			{ 3389, 2805, 2237 },

			{ 3415, 2694, 2195 },

			{ 3356, 2724, 2244 },

		};



		priv->ptat[0] = 2631;

		priv->ptat[1] = 1509;

		priv->ptat[2] = 435;



		for (i = 0; i < priv->num_tscs; i++) {

			struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i];



			tsc->thcode[0] = thcodes[i][0];

			tsc->thcode[1] = thcodes[i][1];

			tsc->thcode[2] = thcodes[i][2];

		}



		return false;

	}



	/*

	 * Set the pseudo calibration points with fused values.

	 * PTAT is shared between all TSCs but only fused for the first

	 * TSC while THCODEs are fused for each TSC.

	 */

	priv->ptat[0] = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_PTAT1) &

		GEN3_FUSE_MASK;

	priv->ptat[1] = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_PTAT2) &

		GEN3_FUSE_MASK;

	priv->ptat[2] = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_PTAT3) &

		GEN3_FUSE_MASK;



	for (i = 0; i < priv->num_tscs; i++) {

		struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i];



		tsc->thcode[0] = rcar_gen3_thermal_read(tsc, REG_GEN3_THCODE1) &

			GEN3_FUSE_MASK;

		tsc->thcode[1] = rcar_gen3_thermal_read(tsc, REG_GEN3_THCODE2) &

			GEN3_FUSE_MASK;

		tsc->thcode[2] = rcar_gen3_thermal_read(tsc, REG_GEN3_THCODE3) &

			GEN3_FUSE_MASK;

	}



	return true;

}



static void rcar_gen3_thermal_init_r8a7795es1(struct rcar_gen3_thermal_tsc *tsc)

{

	rcar_gen3_thermal_write(tsc, REG_GEN3_CTSR,  CTSR_THBGR);
@@ -393,16 +458,6 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev) 
	unsigned int i;

	int ret;



	/* Default THCODE values in case FUSEs are not set. */

	/* TODO: Read values from hardware on supported platforms */

	static const int thcodes[TSC_MAX_NUM][3] = {

		{ 3397, 2800, 2221 },

		{ 3393, 2795, 2216 },

		{ 3389, 2805, 2237 },

		{ 3415, 2694, 2195 },

		{ 3356, 2724, 2244 },

	};



	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);

	if (!priv)

		return -ENOMEM;
@@ -411,10 +466,6 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev) 
	if (soc_device_match(r8a7795es1))

		priv->thermal_init = rcar_gen3_thermal_init_r8a7795es1;



	priv->ptat[0] = 2631;

	priv->ptat[1] = 1509;

	priv->ptat[2] = 435;



	platform_set_drvdata(pdev, priv);



	if (rcar_gen3_thermal_request_irqs(priv, pdev))
@@ -442,11 +493,16 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev) 
			goto error_unregister;

		}



		tsc->thcode[0] = thcodes[i][0];

		tsc->thcode[1] = thcodes[i][1];

		tsc->thcode[2] = thcodes[i][2];



		priv->tscs[i] = tsc;

	}



	priv->num_tscs = i;



	if (!rcar_gen3_thermal_read_fuses(priv))

		dev_info(dev, "No calibration values fused, fallback to driver values\n");



	for (i = 0; i < priv->num_tscs; i++) {

		struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i];



		zone = devm_thermal_zone_of_sensor_register(dev, i, tsc,

							    &rcar_gen3_tz_of_ops);
@@ -476,8 +532,6 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev) 
		dev_info(dev, "TSC%u: Loaded %d trip points\n", i, ret);

	}



	priv->num_tscs = i;



	if (!priv->num_tscs) {

		ret = -ENODEV;

		goto error_unregister;