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: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
---
* Changes since RFT
- Keep thcodes array static.
---
drivers/thermal/rcar_gen3_thermal.c | 94 +++++++++++++++++++++++------
1 file changed, 74 insertions(+), 20 deletions(-)
diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c
index 7d7e6ebe837a83af..897b625e1b498f05 100644
--- a/drivers/thermal/rcar_gen3_thermal.c
+++ b/drivers/thermal/rcar_gen3_thermal.c
@@ -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_update_fuses(struct rcar_gen3_thermal_priv *priv)
+{
+ unsigned int i;
+ u32 thscp;
+
+ /* 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 },
+ };
+
+ /* 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) {
+ 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_update_fuses(priv))
+ dev_info(dev, "Using fused calibration 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;
--
2.33.0
