On Mon, Mar 13, 2023 at 08:27:02PM +0800, Andrew Cooper wrote: > On 13/03/2023 12:21 pm, Roger Pau Monné wrote: > > On Mon, Mar 13, 2023 at 11:55:56AM +0000, Andrew Cooper wrote: > >> On 12/03/2023 7:54 am, Huang Rui wrote: > >>> From: Roger Pau Monne <roger....@citrix.com> > >>> > >>> The VFCT ACPI table is used by AMD GPUs to expose the vbios ROM image > >>> from the firmware instead of doing it on the PCI ROM on the physical > >>> device. > >>> > >>> As such, this needs to be available for PVH dom0 to access, or else > >>> the GPU won't work. > >>> > >>> Reported-by: Huang Rui <ray.hu...@amd.com> > >>> Signed-off-by: Roger Pau Monné <roger....@citrix.com> > >>> Acked-and-Tested-by: Huang Rui <ray.hu...@amd.com> > >>> Release-acked-by: Henry Wang <henry.w...@arm.com> > >>> Signed-off-by: Huang Rui <ray.hu...@amd.com> > >> Huh... Despite the release ack, this didn't get committed for 4.17. > > There was a pending query from Jan as to where was this table > > signature documented or at least registered, as it's not in the ACPI > > spec or any related files. > > > > I don't oppose to the change, as it's already used by Linux, so I > > think it's impossible for the table signature to be reused, even if > > not properly documented (it would cause havoc). > > > > It's however not ideal to set this kind of precedents. > > It's not great, but this exists in real systems, for several generations > it seems. > > Making things work for users trumps any idealistic beliefs about > firmware actually conforming to spec. >
Thanks Andrew for understanding! These tables have been there for more than 10+ years on all AMD GPU platforms. Thanks, Ray
