[PATCH] drm/amdgpu: fix the Carrizo UVD hang on system reboot

[Evan Quan]

It's confirmed that on some APUs the interaction with SMU about DPM disablement
will power off the UVD completely. Thus the succeeding interactions with UVD
during the reboot will trigger hard hang. To workaround this issue, we will skip
the dpm disablement on APUs.

Signed-off-by: Evan Quan <evan.quan at amd.com>
Change-Id: I4340cc2fb0fd94f439cbac5d4963fe920866bc13
---
 drivers/gpu/drm/amd/amdgpu/uvd_v4_2.c | 20 ++++++++++--------
 drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c | 30 +++++++++++++++++++--------
 drivers/gpu/drm/amd/amdgpu/vce_v2_0.c | 18 +++++++++-------
 drivers/gpu/drm/amd/amdgpu/vce_v3_0.c | 18 +++++++++-------
 4 files changed, 52 insertions(+), 34 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/uvd_v4_2.c b/drivers/gpu/drm/amd/amdgpu/uvd_v4_2.c
index c108b8381795..67ec13622e51 100644
--- a/drivers/gpu/drm/amd/amdgpu/uvd_v4_2.c
+++ b/drivers/gpu/drm/amd/amdgpu/uvd_v4_2.c
@@ -238,15 +238,17 @@ static int uvd_v4_2_suspend(void *handle)
 	 */
 	cancel_delayed_work_sync(&adev->uvd.idle_work);
 
-	if (adev->pm.dpm_enabled) {
-		amdgpu_dpm_enable_uvd(adev, false);
-	} else {
-		amdgpu_asic_set_uvd_clocks(adev, 0, 0);
-		/* shutdown the UVD block */
-		amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
-						       AMD_PG_STATE_GATE);
-		amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
-						       AMD_CG_STATE_GATE);
+	if (!(adev->flags & AMD_IS_APU)) {
+		if (adev->pm.dpm_enabled) {
+			amdgpu_dpm_enable_uvd(adev, false);
+		} else {
+			amdgpu_asic_set_uvd_clocks(adev, 0, 0);
+			/* shutdown the UVD block */
+			amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
+							       AMD_PG_STATE_GATE);
+			amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
+							       AMD_CG_STATE_GATE);
+		}
 	}
 
 	r = uvd_v4_2_hw_fini(adev);
diff --git a/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c b/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c
index 2d558c2f417d..60d05ec8c953 100644
--- a/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c
@@ -560,15 +560,27 @@ static int uvd_v6_0_suspend(void *handle)
 	 */
 	cancel_delayed_work_sync(&adev->uvd.idle_work);
 
-	if (adev->pm.dpm_enabled) {
-		amdgpu_dpm_enable_uvd(adev, false);
-	} else {
-		amdgpu_asic_set_uvd_clocks(adev, 0, 0);
-		/* shutdown the UVD block */
-		amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
-						       AMD_PG_STATE_GATE);
-		amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
-						       AMD_CG_STATE_GATE);
+	/*
+	 * It's confirmed that on some APUs the interaction with SMU(about DPM disablement)
+	 * will power off the UVD. That will make the succeeding interactions with UVD on the
+	 * suspend path impossible. And the system will hang due to that. To workaround the
+	 * issue, we will skip the dpm disablement on APUs.
+	 *
+	 * TODO: a better solution is to reorg the action chains performed on suspend and make
+	 * the dpm disablement the last one. But that will involve a lot and needs MM team's
+	 * help.
+	 */
+	if (!(adev->flags & AMD_IS_APU)) {
+		if (adev->pm.dpm_enabled) {
+			amdgpu_dpm_enable_uvd(adev, false);
+		} else {
+			amdgpu_asic_set_uvd_clocks(adev, 0, 0);
+			/* shutdown the UVD block */
+			amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
+							       AMD_PG_STATE_GATE);
+			amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_UVD,
+							       AMD_CG_STATE_GATE);
+		}
 	}
 
 	r = uvd_v6_0_hw_fini(adev);
diff --git a/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c b/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c
index 67eb01fef789..8aa9d8c07053 100644
--- a/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c
@@ -505,14 +505,16 @@ static int vce_v2_0_suspend(void *handle)
 	 */
 	cancel_delayed_work_sync(&adev->vce.idle_work);
 
-	if (adev->pm.dpm_enabled) {
-		amdgpu_dpm_enable_vce(adev, false);
-	} else {
-		amdgpu_asic_set_vce_clocks(adev, 0, 0);
-		amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
-						       AMD_PG_STATE_GATE);
-		amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
-						       AMD_CG_STATE_GATE);
+	if (!(adev->flags & AMD_IS_APU)) {
+		if (adev->pm.dpm_enabled) {
+			amdgpu_dpm_enable_vce(adev, false);
+		} else {
+			amdgpu_asic_set_vce_clocks(adev, 0, 0);
+			amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
+							       AMD_PG_STATE_GATE);
+			amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
+							       AMD_CG_STATE_GATE);
+		}
 	}
 
 	r = vce_v2_0_hw_fini(adev);
diff --git a/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c b/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c
index 142e291983b4..b177cd442838 100644
--- a/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c
@@ -520,14 +520,16 @@ static int vce_v3_0_suspend(void *handle)
 	 */
 	cancel_delayed_work_sync(&adev->vce.idle_work);
 
-	if (adev->pm.dpm_enabled) {
-		amdgpu_dpm_enable_vce(adev, false);
-	} else {
-		amdgpu_asic_set_vce_clocks(adev, 0, 0);
-		amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
-						       AMD_PG_STATE_GATE);
-		amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
-						       AMD_CG_STATE_GATE);
+	if (!(adev->flags & AMD_IS_APU)) {
+		if (adev->pm.dpm_enabled) {
+			amdgpu_dpm_enable_vce(adev, false);
+		} else {
+			amdgpu_asic_set_vce_clocks(adev, 0, 0);
+			amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
+							       AMD_PG_STATE_GATE);
+			amdgpu_device_ip_set_clockgating_state(adev, AMD_IP_BLOCK_TYPE_VCE,
+							       AMD_CG_STATE_GATE);
+		}
 	}
 
 	r = vce_v3_0_hw_fini(adev);
-- 
2.29.0