[PATCH 4.16 222/272] drm/amdgpu: disable GFX ring and disable PQ wptr in hw_fini

Greg Kroah-Hartman
2018-05-28T11:32:45Z

From: Monk Liu <Monk.Liu@amd.com>

[ Upstream commit 9f0178fb67699992d38601cb923b434f9986dd68 ]

otherwise there will be DMAR reading error comes out from CP since
GFX is still alive and CPC's WPTR_POLL is still enabled, which would
lead to DMAR read error.

fix:
we can hault CPG after hw_fini, but cannot halt CPC becaues KIQ
stil need to be alive to let RLCV invoke, but its WPTR_POLL could
be disabled.

Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
@@ -2954,7 +2954,13 @@ static int gfx_v9_0_hw_fini(void *handle
gfx_v9_0_kcq_disable(&adev->gfx.kiq.ring, &adev->gfx.compute_ring[i]);

if (amdgpu_sriov_vf(adev)) {
- pr_debug("For SRIOV client, shouldn't do anything.\n");
+ gfx_v9_0_cp_gfx_enable(adev, false);
+ /* must disable polling for SRIOV when hw finished, otherwise
+ * CPC engine may still keep fetching WB address which is already
+ * invalid after sw finished and trigger DMAR reading error in
+ * hypervisor side.
+ */
+ WREG32_FIELD15(GC, 0, CP_PQ_WPTR_POLL_CNTL, EN, 0);
return 0;
}
gfx_v9_0_cp_enable(adev, false);