Re: [PATCH v2] virtio-gpu: add VIRTIO_GPU_F_EDID feature

From: Gerd Hoffmann
Date: Fri Oct 05 2018 - 11:55:09 EST


Hi,

> >>> +/* VIRTIO_GPU_RESP_OK_EDID */
> >>> +struct virtio_gpu_resp_edid {
> >>> + struct virtio_gpu_ctrl_hdr hdr;
> >>> + __le32 scanout;
> >>> + __le32 size;
> >>> + __u8 edid[1024];
> >>
> >> Wouldnât it be enough to stick to EDID 2.0 (256 bytes)?
> >>
> >> If not, maybe add comment to explain why you chose 1024.
> >
> > EDID in the wild can be up to 512 bytes.
>
> Does this return a physical EDID? I thought it would be made-up by virtio-gpu.

Well, edid has extensions, so it can become pretty large in theory, and
I've figured it would be a good idea to leave some room just in case.
It should be a rather infrequent operation, so the unused buffer space
should not hurt much.

Yes, it will be a edid generated by qemu. The current generator code will
use at most 256 bytes.

cheers,
Gerd