[PATCH 3/7] drm/amdgpu/gmc11: don't touch gfxhub registers during S0ix

[Alex Deucher <alexander.deucher@amd.com>]

gfxhub registers are part of gfx IP and should not need to be
changed.  Doing so without disabling gfxoff can hang the gfx IP.

v2: add comments explaining why we can skip the interrupt
    control for S0i3

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
index 4326078689cd..5e0018fe7e7d 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v11_0.c
@@ -64,13 +64,25 @@ gmc_v11_0_vm_fault_interrupt_state(struct amdgpu_device *adev,
 		/* MM HUB */
 		amdgpu_gmc_set_vm_fault_masks(adev, AMDGPU_MMHUB_0, false);
 		/* GFX HUB */
-		amdgpu_gmc_set_vm_fault_masks(adev, AMDGPU_GFXHUB_0, false);
+		/* This works because this interrupt is only
+		 * enabled at init/resume and disabled in
+		 * fini/suspend, so the overall state doesn't
+		 * change over the course of suspend/resume.
+		 */
+		if (!adev->in_s0ix)
+			amdgpu_gmc_set_vm_fault_masks(adev, AMDGPU_GFXHUB_0, false);
 		break;
 	case AMDGPU_IRQ_STATE_ENABLE:
 		/* MM HUB */
 		amdgpu_gmc_set_vm_fault_masks(adev, AMDGPU_MMHUB_0, true);
 		/* GFX HUB */
-		amdgpu_gmc_set_vm_fault_masks(adev, AMDGPU_GFXHUB_0, true);
+		/* This works because this interrupt is only
+		 * enabled at init/resume and disabled in
+		 * fini/suspend, so the overall state doesn't
+		 * change over the course of suspend/resume.
+		 */
+		if (!adev->in_s0ix)
+			amdgpu_gmc_set_vm_fault_masks(adev, AMDGPU_GFXHUB_0, true);
 		break;
 	default:
 		break;
-- 
2.38.1