On 2018-04-05 09:27 PM, Alex Deucher wrote: > On Thu, Apr 5, 2018 at 2:26 PM, Andrey Grodzovsky > <andrey.grodzovsky at amd.com> wrote: >> From: Alex Deucher <alexander.deucher at amd.com> >> >> The vbios uses memory from the start of vram for the pre-OS >> framebuffer. Reserve this at driver load time to prevent >> the driver from using it for other things which may cause >> atrifacts on screen before the console has kicked in. >> >> Signed-off-by: Alex Deucher <alexander.deucher at amd.com> >> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky at amd.com> [...] >> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c >> index d71d4cb..c8c5ca2 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c >> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c >> @@ -1096,7 +1096,7 @@ static int gmc_v8_0_sw_init(void *handle) >> */ >> adev->gmc.mc_mask = 0xffffffffffULL; /* 40 bit MC */ >> >> - adev->gmc.stolen_size = 256 * 1024; >> + adev->gmc.stolen_size = 32 * 1024 * 1024; > > For platforms that might have limited carve out (ST, CZ, RV), we may > want to do something like: > if (adev->gmc.real_vram_size <= 32MB) // 128MB? > stolen_size = 256K; That means artifacts are likely to still occur during initialization on systems where we only reserve 256K, right? I wonder if there's no way to determine which part of VRAM is being scanned out. If there was, we could just create a normal BO covering that, which would get destroyed once no CRTC references it anymore. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer
