drm/amd/pm: adjust the visibility of pp_table sysfs node

v1:
- make pp_table invisible on VF mode (only valid on BM)
- make pp_table invisible on Mi* chips (Not supported)
- make pp_table invisible if scpm feature is enabled.

v2:
move pp_table invisible code logic into amdgpu_dpm_get_pp_table() function.

v3:
add table buffer pointer check both on powerplay & swsmu.

Signed-off-by: Yang Wang <[e-mail]>
Reviewed-by: Lijo Lazar <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/pm/amdgpu_dpm.c

···
 	const struct amd_pm_funcs *pp_funcs = adev->powerplay.pp_funcs;
 	int ret = 0;
 
-	if (!pp_funcs->get_pp_table)
-		return 0;
+	if (!table)
+		return -EINVAL;
+
+	if (amdgpu_sriov_vf(adev) || !pp_funcs->get_pp_table || adev->scpm_enabled)
+		return -EOPNOTSUPP;
 
 	mutex_lock(&adev->pm.mutex);
 	ret = pp_funcs->get_pp_table(adev->powerplay.pp_handle,
···
 	const struct amd_pm_funcs *pp_funcs = adev->powerplay.pp_funcs;
 	int ret = 0;
 
-	if (!pp_funcs->set_pp_table)
+	if (!buf || !size)
+		return -EINVAL;
+
+	if (amdgpu_sriov_vf(adev) || !pp_funcs->set_pp_table || adev->scpm_enabled)
 		return -EOPNOTSUPP;
 
 	mutex_lock(&adev->pm.mutex);

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

···
 	AMDGPU_DEVICE_ATTR_RO(pp_num_states,				ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF),
 	AMDGPU_DEVICE_ATTR_RO(pp_cur_state,				ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF),
 	AMDGPU_DEVICE_ATTR_RW(pp_force_state,				ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF),
-	AMDGPU_DEVICE_ATTR_RW(pp_table,					ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF),
+	AMDGPU_DEVICE_ATTR_RW(pp_table,					ATTR_FLAG_BASIC),
 	AMDGPU_DEVICE_ATTR_RW(pp_dpm_sclk,				ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF,
 			      .attr_update = pp_dpm_clk_default_attr_update),
 	AMDGPU_DEVICE_ATTR_RW(pp_dpm_mclk,				ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF,
···
 		if (amdgpu_dpm_get_apu_thermal_limit(adev, &limit) ==
 		    -EOPNOTSUPP)
 			*states = ATTR_STATE_UNSUPPORTED;
+	} else if (DEVICE_ATTR_IS(pp_table)) {
+		int ret;
+		char *tmp = NULL;
+
+		ret = amdgpu_dpm_get_pp_table(adev, &tmp);
+		if (ret == -EOPNOTSUPP || !tmp)
+			*states = ATTR_STATE_UNSUPPORTED;
+		else
+			*states = ATTR_STATE_SUPPORTED;
 	}
 
 	switch (gc_ver) {

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

···
 {
 	struct pp_hwmgr *hwmgr = handle;
 
-	if (!hwmgr || !hwmgr->pm_en || !hwmgr->soft_pp_table)
+	if (!hwmgr || !hwmgr->pm_en || !table)
 		return -EINVAL;
+
+	if (!hwmgr->soft_pp_table)
+		return -EOPNOTSUPP;
 
 	*table = (char *)hwmgr->soft_pp_table;
 	return hwmgr->soft_pp_table_size;

drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c

···
 		return -EOPNOTSUPP;
 
 	if (!smu_table->power_play_table && !smu_table->hardcode_pptable)
-		return -EINVAL;
+		return -EOPNOTSUPP;
 
 	if (smu_table->hardcode_pptable)
 		*table = smu_table->hardcode_pptable;