With IOMMU enabled, if SDPIF_MMIO_CNTRL_0 is not set appropriately the system hangs without any trace during S3. To ease debug and to ensure that the failure, if any, was caused by a race conditions that disabled write access to SDPIF_MMIO_CNTRL_0 register, warn the user about it. Signed-off-by: Shirish S <shirish.s@xxxxxxx> --- drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c index d0645ad3446e..fc2d88dbe828 100644 --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c @@ -1546,8 +1546,11 @@ static void gmc_v9_0_init_golden_registers(struct amdgpu_device *adev) */ void gmc_v9_0_restore_registers(struct amdgpu_device *adev) { - if (adev->asic_type == CHIP_RAVEN) + if (adev->asic_type == CHIP_RAVEN) { WREG32_SOC15(DCE, 0, mmDCHUBBUB_SDPIF_MMIO_CNTRL_0, adev->gmc.sdpif_register); + WARN_ON(adev->gmc.sdpif_register != + RREG32_SOC15(DCE, 0, mmDCHUBBUB_SDPIF_MMIO_CNTRL_0); + } } /** -- 2.17.1 _______________________________________________ amd-gfx mailing list amd-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/amd-gfx