drm/amdgpu/gfx8: reset compute ring wptr on the GPU on resume

eemikh · gregkh · commit 228ad2ab5b33 · 2025-07-24T08:56:23.000+02:00
commit 8326193 upstream. Commit 42cdf6f ("drm/amdgpu/gfx8: always restore kcq MQDs") made the ring pointer always to be reset on resume from suspend. This caused compute rings to fail since the reset was done without also resetting it for the firmware. Reset wptr on the GPU to avoid a disconnect between the driver and firmware wptr. Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3911 Fixes: 42cdf6f ("drm/amdgpu/gfx8: always restore kcq MQDs") Signed-off-by: Eeli Haapalainen <eeli.haapalainen@protonmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 2becafc) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
@@ -4652,6 +4652,7 @@ static int gfx_v8_0_kcq_init_queue(struct amdgpu_ring *ring)
 			memcpy(mqd, adev->gfx.mec.mqd_backup[mqd_idx], sizeof(struct vi_mqd_allocation));
 		/* reset ring buffer */
 		ring->wptr = 0;
+		atomic64_set((atomic64_t *)ring->wptr_cpu_addr, 0);
 		amdgpu_ring_clear_ring(ring);
 	}
 	return 0;

Original file line number	Diff line number	Diff line change
`@@ -4652,6 +4652,7 @@ static int gfx_v8_0_kcq_init_queue(struct amdgpu_ring *ring)`
`4652`	`4652`	`memcpy(mqd, adev->gfx.mec.mqd_backup[mqd_idx], sizeof(struct vi_mqd_allocation));`
`4653`	`4653`	`/* reset ring buffer */`
`4654`	`4654`	`ring->wptr = 0;`
	`4655`	`+ atomic64_set((atomic64_t *)ring->wptr_cpu_addr, 0);`
`4655`	`4656`	`amdgpu_ring_clear_ring(ring);`
`4656`	`4657`	`}`
`4657`	`4658`	`return 0;`