[PATCH 4/5] thermal: intel: int340x: Add module parameter to change slider offset

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

The slider offset value allows the SoC to automatically switch slider
positions in range [SOC_SLIDER … (SOC_SLIDER + slider offset)] based on
internal algorithms to improve power efficiency.

By default, the SoC slider offset is set to 0. This means that SoC is not
allowed to switch slider position.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 .../processor_thermal_soc_slider.c            | 41 +++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_soc_slider.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_soc_slider.c
index ffc538c9b9e3..bd4ff26a488b 100644
--- a/drivers/thermal/intel/int340x_thermal/processor_thermal_soc_slider.c
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_soc_slider.c
@@ -87,6 +87,40 @@ static const struct kernel_param_ops slider_def_balance_ops = {
 module_param_cb(slider_balance, &slider_def_balance_ops, NULL, 0644);
 MODULE_PARM_DESC(slider_balance, "Set slider default value for balance.");
 
+static u8 slider_offset;
+
+static int slider_def_offset_set(const char *arg, const struct kernel_param *kp)
+{
+	u8 offset;
+	int ret;
+
+	guard(mutex)(&slider_param_lock);
+
+	ret = kstrtou8(arg, 16, &offset);
+	if (!ret) {
+		if (offset > SOC_SLIDER_VALUE_MAXIMUM)
+			return -EINVAL;
+
+		slider_offset = offset;
+	}
+
+	return ret;
+}
+
+static int slider_def_offset_get(char *buf, const struct kernel_param *kp)
+{
+	guard(mutex)(&slider_param_lock);
+	return sysfs_emit(buf, "%02x\n", slider_offset);
+}
+
+static const struct kernel_param_ops slider_offset_ops = {
+	.set = slider_def_offset_set,
+	.get = slider_def_offset_get,
+};
+
+module_param_cb(slider_offset, &slider_offset_ops, NULL, 0644);
+MODULE_PARM_DESC(slider_offset, "Set slider offset.");
+
 /* Convert from platform power profile option to SoC slider value */
 static int convert_profile_to_power_slider(enum platform_profile_option profile)
 {
@@ -120,6 +154,8 @@ static int convert_power_slider_to_profile(u8 slider)
 #define SLIDER_MASK		GENMASK_ULL(2, 0)
 #define SLIDER_ENABLE_BIT	7
 
+#define SLIDER_OFFSET_MASK	GENMASK_ULL(6, 4)
+
 static void set_soc_power_profile(struct proc_thermal_device *proc_priv, int slider)
 {
 	u64 val;
@@ -128,6 +164,11 @@ static void set_soc_power_profile(struct proc_thermal_device *proc_priv, int sli
 	val &= ~SLIDER_MASK;
 	val |= FIELD_PREP(SLIDER_MASK, slider);
 	val |= BIT(SLIDER_ENABLE_BIT);
+
+	/* Set the slider offset from module params */
+	val &= ~SLIDER_OFFSET_MASK;
+	val |= FIELD_PREP(SLIDER_OFFSET_MASK, slider_offset);
+
 	writeq(val, proc_priv->mmio_base + SOC_POWER_SLIDER_OFFSET);
 }
 
-- 
2.43.0