On 4/20/2022 7:32 AM, Prike Liang wrote:
Without MMHUB clock gating being enabled then MMHUB will not disconnect
from DF and will result in DF C-state entry can't be accessed during S2idle
suspend, and eventually s0ix entry will be blocked.
Signed-off-by: Prike Liang <Prike.Liang@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/mmhub_v2_3.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/mmhub_v2_3.c b/drivers/gpu/drm/amd/amdgpu/mmhub_v2_3.c
index 1957fb098c4d..cb3dca4834b4 100644
--- a/drivers/gpu/drm/amd/amdgpu/mmhub_v2_3.c
+++ b/drivers/gpu/drm/amd/amdgpu/mmhub_v2_3.c
@@ -568,6 +568,15 @@ static int mmhub_v2_3_set_clockgating(struct amdgpu_device *adev,
{
if (amdgpu_sriov_vf(adev))
return 0;
+ /*
+ * The issue mmhub can't disconnect from DF with clock gating being disabled
+ * seems only observed at DF 3.0.3, with the same suspend sequence not seen
+ * any issue on the DF 3.0.2 series platform.
+ */
+ if (adev->in_s0ix) {
+ dev_dbg(adev->dev, "keep mmhub clock gating being enabled for s0ix\n");
+ return 0;
+ }
A better fix would be to explicitly enable mmhub clockgating during s0ix
suspend of gmc for this IP version.
Thanks,
Lijo
mmhub_v2_3_update_medium_grain_clock_gating(adev,
state == AMD_CG_STATE_GATE);
