From 920e3c77f13084206949730f0d0d0a797425c4e7 Mon Sep 17 00:00:00 2001
From: Guchun Chen <guchun.chen@amd.com>
Date: Fri, 27 Aug 2021 18:31:41 +0800
Subject: [PATCH] drm/amdgpu: stop scheduler when calling hw_fini (v2)
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Git-commit: f7d6779df642720e22bffd449e683bb8690bd3bf
Patch-mainline: v5.15-rc1
References: stable-5.14.10

[ Upstream commit f7d6779df642720e22bffd449e683bb8690bd3bf ]

This gurantees no more work on the ring can be submitted
to hardware in suspend/resume case, otherwise a potential
race will occur and the ring will get no chance to stay
empty before suspend.

V2: Call drm_sched_resubmit_job before drm_sched_start to
restart jobs from the pending list.

Suggested-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Guchun Chen <guchun.chen@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
index 7495911516c2..49884069226a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
@@ -532,6 +532,9 @@ void amdgpu_fence_driver_hw_fini(struct amdgpu_device *adev)
 		if (!ring || !ring->fence_drv.initialized)
 			continue;
 
+		if (!ring->no_scheduler)
+			drm_sched_stop(&ring->sched, NULL);
+
 		/* You can't wait for HW to signal if it's gone */
 		if (!drm_dev_is_unplugged(&adev->ddev))
 			r = amdgpu_fence_wait_empty(ring);
@@ -591,6 +594,11 @@ void amdgpu_fence_driver_hw_init(struct amdgpu_device *adev)
 		if (!ring || !ring->fence_drv.initialized)
 			continue;
 
+		if (!ring->no_scheduler) {
+			drm_sched_resubmit_jobs(&ring->sched);
+			drm_sched_start(&ring->sched, true);
+		}
+
 		/* enable the interrupt */
 		if (ring->fence_drv.irq_src)
 			amdgpu_irq_get(adev, ring->fence_drv.irq_src,
-- 
2.26.2