Igor Skochinsky via coreboot <[email protected]> writes: > Hello Patrick, > > Tuesday, April 4, 2017, 8:54:09 PM, you wrote: > > PR> VBT is documented by intel-gpu-tools. There's intel_vbt_decode > PR> (former intel_bios_decode) available > PR> > https://cgit.freedesktop.org/xorg/app/intel-gpu-tools/tree/tools/intel_vbt_decode.c > PR> that will print all tables in human readable form. > > Nice find! I did not realize this tool supports that many structures; > for some reason I thought it just prints some general info without details. > > So now that we have a dumper the following should be possible: > 1) make a "decompiler" that would convert VBT from the option ROM into a > human/machine > readable text format > 2) make a "compiler" that would take that text format and create a > binary VBT from it > 3) put the binary VBT into the ACPI IGD OpRegion table ([1], [2]), or > wherever the graphics driver can find it. >
I think blobtool would fit that purpose quite nicely on the assumption VBT is already extracted and that VBT has fixed locations for its entries. If one writes a blobtool spec file (which describes the bitfields) it can serve both as a "decompiler" and as a "compiler". >So, basically, an approach similar to ich9gen for the flash >descriptor/gbe. Blobtool handles ICH9 IFD and GBE compilation and decompilation too. ;) >This should allow getting rid of the option ROM if real mode support is >not required. Would great to have indeed, who knows if other OS drivers will mandate VBT one day. Kind regards. -- Arthur Heymans -- coreboot mailing list: [email protected] https://www.coreboot.org/mailman/listinfo/coreboot
