Issue #665 has been updated by Walter Sonius.
Sorry for mixing up the VBIOS term, I ment dumped rom/bin which on a physical external dGPU's may contain both VBIOS(legacy) and efi(GOP) in the same dump. Will try to debug this further on a "Desktop PC" with a working EDK2 serial port since it will lack any display output by the iGPU because libgfxinit has to be disabled to force EDK2 do the enabling using your current intel only (CBFS efi GOP + VBT) method. Modify this method to not load intel efi GOP but a efi GOP(without VBT) from a AMD polaris dGPU RX460 (for which I can erase/restore its physical ROM with a ch341a programmer already tested) or try with EDK2 shell command to run something like [`loadpcirom`](https://www.highpoint-tech.com/post/how-to-load-the-uefi-rom-manually). If it somehow works for the AMD dGPU I will try a PC dGPU Nvidia GTX640 for which its VBIOS was converted to efi GOP in the past by kepler BIOS editor/ UEFI enabler, perhaps I can transform the macbookpro NVIDIA dGPU legacy VBIOS dump with a similar [kepler UEFI updater](https://winraid.level1techs.com/t/kepler-uefi-updater/30574) still have try though. ---------------------------------------- Bug #665: Does EDK2 MrChromeBox support integrated dGPU uga/gop VBIOS file from CBFS? https://ticket.coreboot.org/issues/665#change-2435 * Author: Walter Sonius * Status: New * Priority: Normal * Target version: none * Start date: 2026-10-04 * Affected hardware: Apple MacBookPro10,1 ---------------------------------------- Does EDK2 MrChromebox 26.09.2 load a VBIOS bin file from CBFS added with `CONFIG_VGA_BIOS` and runs it like SeaBIOS does for laptops with dGPU? Tried it with and without the `CONFIG_EDK2_LOAD_OPTION_ROMS:y` setting? For a while EDK2 MrChromeBox payload caries support for loading VBIOS from real physical PCIe dGPU's using `CONFIG_EDK2_LOAD_OPTION_ROMS:y` if they have a matching 64-bit EFI GOP. This has worked fine for me on real desktop boards with PCIe dGPU's from sandybridge to coffeelake both with AMD and NVIDIA dGPU's even combined with libgfxinit intel iGPU's. Currently on coreboot 26.09-14-ge0eec9336f54 for the macbookpro10,1 [CB:32673](https://review.coreboot.org/c/coreboot/+/32673) it works fine with SeaBIOS 1.17. Switching from only Intel to only NVIDIA keeps SeaBIOS bootscreen and makes built-in display, both miniDP and HDMI output work if using NVIDIA. While only using `CONFIG_VGA_BIOS` with `10de,0fd5` a `uefiextract` supplied VBIOS bin and not even using the Kconfig `2nd` or `discrete` VGA options (since the Intel iGPU uses libgfxinit). When using EDK2 MrChromebox 26.09.2 forced to only NVIDIA the built-in display remains off during post/boot (no bunny neither on both miniDP ports nor HDMI port). However the OS nouveau driver detects the VBIOS in its CBFS/ACPI table and all video outputs start working fine including sound output. Currently only Intel iGPU output works fine with EDK2 bootscreen. Any thoughts how to debug or even research if my VBIOS file has a correct EFI GOP in it? By default both EDK2 and SeaBIOS builds are build with libgfxinit support and not using the coreboot way of running the VBIOS from CBFS but let the payload do it which works for SeaBIOS. -- You have received this notification because you have either subscribed to it, or are involved in it. To change your notification preferences, please click here: https://ticket.coreboot.org/my/account _______________________________________________ coreboot mailing list -- [email protected] To unsubscribe send an email to [email protected]
