drm/amd/pp: Add stable Pstate clk display support in debugfs

The additional output are: PSTATE_SCLK and PSTATE_MCLK value
in MHz as:

300 MHz (PSTATE_SCLK)
300 MHz (PSTATE_MCLK)
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c

@@ -1591,6 +1591,10 @@ static int amdgpu_debugfs_pm_info_pp(struct seq_file *m, struct amdgpu_device *a
 		seq_printf(m, "\t%u MHz (MCLK)\n", value/100);
 	if (!amdgpu_dpm_read_sensor(adev, AMDGPU_PP_SENSOR_GFX_SCLK, (void *)&value, &size))
 		seq_printf(m, "\t%u MHz (SCLK)\n", value/100);
+	if (!amdgpu_dpm_read_sensor(adev, AMDGPU_PP_SENSOR_STABLE_PSTATE_SCLK, (void *)&value, &size))
+		seq_printf(m, "\t%u MHz (PSTATE_SCLK)\n", value/100);
+	if (!amdgpu_dpm_read_sensor(adev, AMDGPU_PP_SENSOR_STABLE_PSTATE_MCLK, (void *)&value, &size))
+		seq_printf(m, "\t%u MHz (PSTATE_MCLK)\n", value/100);
 	if (!amdgpu_dpm_read_sensor(adev, AMDGPU_PP_SENSOR_VDDGFX, (void *)&value, &size))
 		seq_printf(m, "\t%u mV (VDDGFX)\n", value);
 	if (!amdgpu_dpm_read_sensor(adev, AMDGPU_PP_SENSOR_VDDNB, (void *)&value, &size))

drivers/gpu/drm/amd/include/kgd_pp_interface.h

@@ -122,6 +122,8 @@ enum amd_pp_sensors {
 	AMDGPU_PP_SENSOR_VCE_POWER,
 	AMDGPU_PP_SENSOR_UVD_POWER,
 	AMDGPU_PP_SENSOR_GPU_POWER,
+	AMDGPU_PP_SENSOR_STABLE_PSTATE_SCLK,
+	AMDGPU_PP_SENSOR_STABLE_PSTATE_MCLK,
 };
 
 enum amd_pp_task {

drivers/gpu/drm/amd/powerplay/amd_powerplay.c

@@ -992,22 +992,27 @@ static int pp_dpm_read_sensor(void *handle, int idx,
 	int ret = 0;
 
 	ret = pp_check(pp_handle);
-
 	if (ret)
 		return ret;
 
+	if (value == NULL)
+		return -EINVAL;
+
 	hwmgr = pp_handle->hwmgr;
 
-	if (hwmgr->hwmgr_func->read_sensor == NULL) {
-		pr_info("%s was not implemented.\n", __func__);
+	switch (idx) {
+	case AMDGPU_PP_SENSOR_STABLE_PSTATE_SCLK:
+		*((uint32_t *)value) = hwmgr->pstate_sclk;
 		return 0;
+	case AMDGPU_PP_SENSOR_STABLE_PSTATE_MCLK:
+		*((uint32_t *)value) = hwmgr->pstate_mclk;
+		return 0;
+	default:
+		mutex_lock(&pp_handle->pp_lock);
+		ret = hwmgr->hwmgr_func->read_sensor(hwmgr, idx, value, size);
+		mutex_unlock(&pp_handle->pp_lock);
+		return ret;
 	}
-
-	mutex_lock(&pp_handle->pp_lock);
-	ret = hwmgr->hwmgr_func->read_sensor(hwmgr, idx, value, size);
-	mutex_unlock(&pp_handle->pp_lock);
-
-	return ret;
 }
 
 static struct amd_vce_state*