drm/amdgpu/hdp6: use memcfg register to post the write for HDP flush

BugLink: https://bugs.launchpad.net/bugs/2112462

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: abe1cbaec6cf ("drm/amdgpu/hdp6.0: 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 84141ff615951359c9a99696fd79a36c465ed847)
Cc: stable@vger.kernel.org
(cherry picked from commit ca28e80abe4219c8f1a2961ae05102d70af6dc87)
Signed-off-by: You-Sheng Yang <vicamo@gmail.com>
Acked-by: Thibault Ferrante <thibault.ferrante@canonical.com>
Acked-by: Edoardo Canepa <edoardo.canepa@canonical.com>
Signed-off-by: Mehmet Basaran <mehmet.basaran@canonical.com>
This commit is contained in:
Alex Deucher
2025-06-06 02:35:26 +08:00
committed by Mehmet Basaran
parent 3bb52ce508
commit 84f10235c8
+6 -1
View File
@@ -36,7 +36,12 @@ static void hdp_v6_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);
}