Re: AMDGPU Driver patches/bugs

[Jeff Frasca <thatguy%jeff-frasca.name@localhost>]

On Fri, Feb 24, 2023 at 9:33 AM matthew green <mrg%eterna.com.au@localhost> wrote:
>
> thanks for your patches and help, Jeff!

Your welcome.  I'm going to keep at it.

> Taylor R Campbell writes:
> > > Date: Tue, 21 Feb 2023 13:20:13 -0800
> > > From: Jeff Frasca <thatguy%jeff-frasca.name@localhost>
> > >
> > > I was going to try the radeon driver again, because I want to see if
> > > my wayland compositor works better against it than the AMDGPU driver
> > > (I'm getting some weird corruption problems with my compositor that
> > > do not happen under Linux, but that's probably my code).
> >
> > We have seen other weird minor graphics corruption problems with X,
> > even with xcompmgr or picom running.  I probably made another stupid
> > bug, maybe in cacheability attributes or something, buried somewhere
> > in the megabytes of diffs...
>
> i see corruption with radeon and bios boot on a ryzen 5600G
> system.  (this is one that fails the ring3 (?) test with UEFI,
> and even with "CSM" in the bios enabled, still attempts to
> load our uefi boot program, which then fails cuz it's in BIOS
> mode and hangs the boot.  with no msdosfs visible to UEFI it
> boots fine in CSM mode.)  i do *not* recall seeing it on my
> older systems (haswell, earlier ryzen.)
>
> i'll try out my amdgpu's next week some time.

So, I expect with the MXCSR patch that Taylor just applied and the other
couple of patches, might get you a blank screen (although, it looks like
the CONFIG_DRM_AND_DC macro isn't getting set still, so you might not
hit the floating point code).  If you don't get a blank screen, it will just
panic, either on attempting to unload the driver or the PSP firmware will
fail to load (it's intermittent, I haven't put much time into figuring
it out, yet).

I expect when you've got the radeon driver turned on, what you are actually
using is the genfb driver and radeon is getting skipped entirely.  The radeon
driver definitely does not support your Ryzen 5600G APU.  (But genfb should
understand the VGA/VESA like output stage for the APU just fine.)

Give it a shot.  Let me know what fails.  I'll go double check the macro I noted
above tonight and bug Taylor to patch it.