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

commit 83261934015c434fabb980a3e613b01d9976e877 upstream.

Commit 42cdf6f687da ("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: 42cdf6f687da ("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 2becafc319db3d96205320f31cc0de4ee5a93747)
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
index 1943beb135c4c2923c211c5727afbd16141ac718..472cb0f9e8f6c0f848a7339846f8d9ffd85cc1c6 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
@@ -4656,6 +4656,7 @@ 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;