On a MacBookPro14,3 with a Radeon Pro 555 (Polaris11), the framebuffer is at MC address 0 when amdgpu loads after a cold boot, as the firmware leaves it (MC_VM_FB_LOCATION = 0x007f0000), while the VBIOS ASIC_Init table places it at 0xF4_0000_0000 (0xf47ff400). amdgpu reads the location once, at init, so after a re-POST (S3 resume or GPU reset) the framebuffer has moved and the driver keeps programming the old one: the SMU is handed a table that was never written and the GPU does not come back, which leaves the internal panel black.
Resetting the ASIC on load makes ASIC_Init run before the driver reads the location, so the driver uses the VBIOS placement from the start and every later re-POST puts the framebuffer back where it already is. Add the Radeon Pro 555 used in this machine to the existing VI reset quirk table. Tested on a MacBookPro14,3 on 6.18.49 with the quirk table backported (the kernel also carries unrelated local PCI and ACPI patches for this machine). The framebuffer is at 0x000000F400000000 after both cold and warm boot, and the GPU survived 9 S3 cycles (lid close and rtcwake, one of them with the lid closed for about 7.5 minutes and a USB-C disk attached), each followed by a few minutes of 3D load; no ring timeouts or VM faults were reported. The reset adds about 0.23 s to amdgpu init. Suggested-by: Christian König <[email protected]> Suggested-by: Alex Deucher <[email protected]> Link: https://lore.kernel.org/all/[email protected]/ Assisted-by: Claude:claude-opus-5-5 Signed-off-by: Francisco Beltrán Millalén <[email protected]> --- v2: new approach, as suggested by Christian and Alex: instead of rewriting MC_VM_FB_LOCATION after every re-POST in gmc_v8_0 (v1, withdrawn), reset the ASIC on load through the existing vi_reset_quirks table. v1: https://lore.kernel.org/all/[email protected]/ drivers/gpu/drm/amd/amdgpu/vi.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/amd/amdgpu/vi.c b/drivers/gpu/drm/amd/amdgpu/vi.c index 2cd6d7d77..a0435fd55 100644 --- a/drivers/gpu/drm/amd/amdgpu/vi.c +++ b/drivers/gpu/drm/amd/amdgpu/vi.c @@ -1397,6 +1397,7 @@ struct vi_reset_quirk { static const struct vi_reset_quirk vi_reset_quirks[] = { { 0x67ef, PCI_VENDOR_ID_APPLE, 0x0190, 0xe3 }, /* Radeon Pro 555X */ { 0x67ef, PCI_VENDOR_ID_APPLE, 0x018f, 0xc2 }, /* Radeon Pro 560X */ + { 0x67ef, PCI_VENDOR_ID_APPLE, 0x017a, 0xc7 }, /* Radeon Pro 555 */ }; static bool vi_need_reset_on_init(struct amdgpu_device *adev) -- 2.55.0
