[PATCH] drm/amd/powerplay: bypass fan table setup if no fan connected

[Hawking Zhang]

If vBIOS noFan bit is set, the fan table parameters in thermal controller
will not get initialized. The driver should avoid to use these uninitialized
parameter to do calculation. Otherwise, it may trigger divide 0 error.

Change-Id: I985119837ec818e2101835f79aa4fe6e0e247797
Signed-off-by: Hawking Zhang <Hawking.Zhang at amd.com>
---
 drivers/gpu/drm/amd/powerplay/smumgr/fiji_smc.c      | 6 ++++++
 drivers/gpu/drm/amd/powerplay/smumgr/iceland_smc.c   | 6 ++++++
 drivers/gpu/drm/amd/powerplay/smumgr/polaris10_smc.c | 6 ++++++
 drivers/gpu/drm/amd/powerplay/smumgr/tonga_smc.c     | 6 ++++++
 4 files changed, 24 insertions(+)

diff --git a/drivers/gpu/drm/amd/powerplay/smumgr/fiji_smc.c b/drivers/gpu/drm/amd/powerplay/smumgr/fiji_smc.c
index 34523fe..a0b9446 100644
--- a/drivers/gpu/drm/amd/powerplay/smumgr/fiji_smc.c
+++ b/drivers/gpu/drm/amd/powerplay/smumgr/fiji_smc.c
@@ -1958,6 +1958,12 @@ int fiji_thermal_setup_fan_table(struct pp_hwmgr *hwmgr)
 	int res;
 	uint64_t tmp64;
 
+	if (hwmgr->thermal_controller.fanInfo.bNoFan) {
+                phm_cap_unset(hwmgr->platform_descriptor.platformCaps,
+			PHM_PlatformCaps_MicrocodeFanControl);
+		return 0;
+	}
+
 	if (smu_data->smu7_data.fan_table_start == 0) {
 		phm_cap_unset(hwmgr->platform_descriptor.platformCaps,
 				PHM_PlatformCaps_MicrocodeFanControl);
diff --git a/drivers/gpu/drm/amd/powerplay/smumgr/iceland_smc.c b/drivers/gpu/drm/amd/powerplay/smumgr/iceland_smc.c
index b579f0c..a24971a 100644
--- a/drivers/gpu/drm/amd/powerplay/smumgr/iceland_smc.c
+++ b/drivers/gpu/drm/amd/powerplay/smumgr/iceland_smc.c
@@ -2006,6 +2006,12 @@ int iceland_thermal_setup_fan_table(struct pp_hwmgr *hwmgr)
 	if (!phm_cap_enabled(hwmgr->platform_descriptor.platformCaps, PHM_PlatformCaps_MicrocodeFanControl))
 		return 0;
 
+	if (hwmgr->thermal_controller.fanInfo.bNoFan) {
+		phm_cap_unset(hwmgr->platform_descriptor.platformCaps,
+			PHM_PlatformCaps_MicrocodeFanControl);
+		return 0;
+	}
+
 	if (0 == smu7_data->fan_table_start) {
 		phm_cap_unset(hwmgr->platform_descriptor.platformCaps, PHM_PlatformCaps_MicrocodeFanControl);
 		return 0;
diff --git a/drivers/gpu/drm/amd/powerplay/smumgr/polaris10_smc.c b/drivers/gpu/drm/amd/powerplay/smumgr/polaris10_smc.c
index 8db8e20..5190e82 100644
--- a/drivers/gpu/drm/amd/powerplay/smumgr/polaris10_smc.c
+++ b/drivers/gpu/drm/amd/powerplay/smumgr/polaris10_smc.c
@@ -1885,6 +1885,12 @@ int polaris10_thermal_setup_fan_table(struct pp_hwmgr *hwmgr)
 	int res;
 	uint64_t tmp64;
 
+	if (hwmgr->thermal_controller.fanInfo.bNoFan) {
+		phm_cap_unset(hwmgr->platform_descriptor.platformCaps,
+			PHM_PlatformCaps_MicrocodeFanControl);
+		return 0;
+	}
+
 	if (smu_data->smu7_data.fan_table_start == 0) {
 		phm_cap_unset(hwmgr->platform_descriptor.platformCaps,
 				PHM_PlatformCaps_MicrocodeFanControl);
diff --git a/drivers/gpu/drm/amd/powerplay/smumgr/tonga_smc.c b/drivers/gpu/drm/amd/powerplay/smumgr/tonga_smc.c
index d08f6f1..2e1493c 100644
--- a/drivers/gpu/drm/amd/powerplay/smumgr/tonga_smc.c
+++ b/drivers/gpu/drm/amd/powerplay/smumgr/tonga_smc.c
@@ -2496,6 +2496,12 @@ int tonga_thermal_setup_fan_table(struct pp_hwmgr *hwmgr)
 					PHM_PlatformCaps_MicrocodeFanControl))
 		return 0;
 
+	if (hwmgr->thermal_controller.fanInfo.bNoFan) {
+		phm_cap_unset(hwmgr->platform_descriptor.platformCaps,
+			PHM_PlatformCaps_MicrocodeFanControl);
+		return 0;
+	}
+
 	if (0 == smu_data->smu7_data.fan_table_start) {
 		phm_cap_unset(hwmgr->platform_descriptor.platformCaps,
 					PHM_PlatformCaps_MicrocodeFanControl);
-- 
2.7.4