diff options
| author | Alex Deucher <alexander.deucher@amd.com> | 2025-04-30 12:45:04 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2025-05-07 18:24:56 -0400 |
| commit | f690e3974755a650259a45d71456decc9c96a282 (patch) | |
| tree | 1b2d42e7024c11c0204393b2ef7a1366db020d87 | |
| parent | 4aaffc85751da5722e858e4333e8cf0aa4b6c78f (diff) | |
drm/amdgpu/hdp4: use memcfg register to post the write for HDP flush
Reading back the remapped HDP flush register seems to cause
problems on some platforms. All we need is a read, so read back
the memcfg register.
Fixes: c9b8dcabb52a ("drm/amdgpu/hdp4.0: do a posting read when flushing HDP")
Reported-by: Alexey Klimov <alexey.klimov@linaro.org>
Link: https://lists.freedesktop.org/archives/amd-gfx/2025-April/123150.html
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4119
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3908
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 5c937b4a6050316af37ef214825b6340b5e9e391)
Cc: stable@vger.kernel.org
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/hdp_v4_0.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/hdp_v4_0.c b/drivers/gpu/drm/amd/amdgpu/hdp_v4_0.c index f1dc13b3ab38..cbbeadeb53f7 100644 --- a/drivers/gpu/drm/amd/amdgpu/hdp_v4_0.c +++ b/drivers/gpu/drm/amd/amdgpu/hdp_v4_0.c @@ -41,7 +41,12 @@ static void hdp_v4_0_flush_hdp(struct amdgpu_device *adev, { if (!ring || !ring->funcs->emit_wreg) { WREG32((adev->rmmio_remap.reg_offset + KFD_MMIO_REMAP_HDP_MEM_FLUSH_CNTL) >> 2, 0); - RREG32((adev->rmmio_remap.reg_offset + KFD_MMIO_REMAP_HDP_MEM_FLUSH_CNTL) >> 2); + /* We just need to read back a register to post the write. + * Reading back the remapped register causes problems on + * some platforms so just read back the memory size register. + */ + if (adev->nbio.funcs->get_memsize) + adev->nbio.funcs->get_memsize(adev); } else { amdgpu_ring_emit_wreg(ring, (adev->rmmio_remap.reg_offset + KFD_MMIO_REMAP_HDP_MEM_FLUSH_CNTL) >> 2, 0); } |