Re: [9front] igfx on haswell

[Kyle Milz <krwmilz@gmail.com>]

On Sat, Nov 13, 2021 at 11:29:31PM +0100, qwx@sciops.net wrote:
> Interesting.  I'll play around with the x240 and retest with my
> desktop, I've never had issues with that one with the monitors
> I've used.  Reading the linux code isn't super helpful though,
> it's just a huge mishmash of incomprehensible and undocumented
> black magic.

yeah i've noticed that. the docs on kernel.org are not a bad
introduction.

> > > If possible, please add the pci did to
> > > /sys/src/9/pc/vgaigfx.c:152.  The hardware cursor should be
> > > enabled when you invoke aux/vga.  If it's visible while
> > > /dev/vgactl shows `hwgc igfxhwgc', it works.
> > 
> > i tried that, but got the same output as before. forcing it with
> > 
> > 	% echo hwgc igfxhwgc >/dev/vgactl
> > 
> > causes the cursor to disappear.
> 
> If you got the same output as before, it might be because you
> haven't updated or installed a new kernel.  Your vgadb diff
> shows that you had inserted the did in the correct ctrl
> section which sets igfxhwgc, so that should happen
> automatically when you boot with whatever params or use
> aux/vga, ie. you shouldn't need to write to /dev/vgactl.  Not
> to say that a bug isn't possible of course!

i've been hacking the kernel already and got installation figured
out, copying into /n/9fat/ in my case. i double checked and
no difference, still 'hgwc soft'. i added some debugging in the
functions of vgaigfx.c and they only fire when i force hwgc to
igfxhwgc as above. so it looks like they are not being triggered
automatically for whatever reason.

> Thanks a lot, I'll push your diff and vgaigfx.c change,
> and please report back about the cursor when possible.
> I think we may now claim that we support broadwell!

haha, i guess for some definition of support :)

is 'hwaccel' ever available for igfx? i understand this would only
be 2D but i was curious why it is off. same for 'hwblank', is that
expected to work?