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| author | Xiaojie Yuan <xiaojie.yuan@amd.com> | 2020-07-14 15:47:31 +0800 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2020-07-14 15:42:17 -0400 |
| commit | 05051496b2622e4d12e2036b35165969aa502f89 (patch) | |
| tree | 772b65efe21dc07bf473e1ce65527acabb433bc7 /drivers | |
| parent | 98a34cf931e848f8489d3fb15a8f5fc03802ad65 (diff) | |
| download | linux-05051496b2622e4d12e2036b35165969aa502f89.tar.bz2 | |
drm/amdgpu/sdma5: fix wptr overwritten in ->get_wptr()
"u64 *wptr" points to the the wptr value in write back buffer and
"*wptr = (*wptr) >> 2;" results in the value being overwritten each time
when ->get_wptr() is called.
umr uses /sys/kernel/debug/dri/0/amdgpu_ring_sdma0 to get rptr/wptr and
decode ring content and it is affected by this issue.
fix and simplify the logic similar as sdma_v4_0_ring_get_wptr().
v2: fix for sdma5.2 as well
v3: drop sdma 5.2 changes for 5.8 and stable
Suggested-by: Le Ma <le.ma@amd.com>
Signed-off-by: Xiaojie Yuan <xiaojie.yuan@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c | 26 |
1 files changed, 8 insertions, 18 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c index 5d71c23e2640..8fb66e50a57b 100644 --- a/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c +++ b/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c @@ -314,30 +314,20 @@ static uint64_t sdma_v5_0_ring_get_rptr(struct amdgpu_ring *ring) static uint64_t sdma_v5_0_ring_get_wptr(struct amdgpu_ring *ring) { struct amdgpu_device *adev = ring->adev; - u64 *wptr = NULL; - uint64_t local_wptr = 0; + u64 wptr; if (ring->use_doorbell) { /* XXX check if swapping is necessary on BE */ - wptr = ((u64 *)&adev->wb.wb[ring->wptr_offs]); - DRM_DEBUG("wptr/doorbell before shift == 0x%016llx\n", *wptr); - *wptr = (*wptr) >> 2; - DRM_DEBUG("wptr/doorbell after shift == 0x%016llx\n", *wptr); + wptr = READ_ONCE(*((u64 *)&adev->wb.wb[ring->wptr_offs])); + DRM_DEBUG("wptr/doorbell before shift == 0x%016llx\n", wptr); } else { - u32 lowbit, highbit; - - wptr = &local_wptr; - lowbit = RREG32(sdma_v5_0_get_reg_offset(adev, ring->me, mmSDMA0_GFX_RB_WPTR)) >> 2; - highbit = RREG32(sdma_v5_0_get_reg_offset(adev, ring->me, mmSDMA0_GFX_RB_WPTR_HI)) >> 2; - - DRM_DEBUG("wptr [%i]high== 0x%08x low==0x%08x\n", - ring->me, highbit, lowbit); - *wptr = highbit; - *wptr = (*wptr) << 32; - *wptr |= lowbit; + wptr = RREG32(sdma_v5_0_get_reg_offset(adev, ring->me, mmSDMA0_GFX_RB_WPTR_HI)); + wptr = wptr << 32; + wptr |= RREG32(sdma_v5_0_get_reg_offset(adev, ring->me, mmSDMA0_GFX_RB_WPTR)); + DRM_DEBUG("wptr before shift [%i] wptr == 0x%016llx\n", ring->me, wptr); } - return *wptr; + return wptr >> 2; } /** |