Re: Samsung P35, S3, black screen (radeon)

Nigel Cunningham
2005-02-03T23:43:39Z

Hi.

On Fri, 2005-02-04 at 09:54, Pavel Machek wrote:
> Hi!
>
> > >>Are you able to use framebuffer(radeonfb,1024x768) with this
> > >>configuration or do you need to use plain vga-console for it to work?
> > >
> > > No.
> > > For a working framebuffer console you would have to perform the steps
> > > my script does *before* the kernel tries to access the framebuffer
> > > console after resume. Since this is not yet possible, you're out of
> > > luck. If
> > > - the vbestate utility was a kernel module or
> >
> > OK, I managed to track this down further.
> > "vbetool post" should be equivalent to "acpi_sleep=s3_bios", but there
> > are some differences. For me, that's easy to explain: "vbetool post"
> > segfaults because it wants to access parts of the video bios which
> > are no longer available. "acpi_sleep=s3_bios" suffers from the same
> > problem, but it runs in real mode and can't recover :-(
> >
> > To alleviate that problem, the kernel could run the video bios in
> > vm86 mode (like vbetool does by using lrmi). This would simplify
> > the asm wakeup code and make video POST more reliable.
> >
> > Pavel, what do you think?
>
> Well, calling BIOS using vm86 is going to be quite a lot of code. If
> it is self-contained and not too huge, it is probably okay. It should
> help with quite a lot of cards, but who knows...
>
> Yes, it is probably worth trying.

I'd love to see it too. Pavel, even if you don't want to merge it for a
while, we can always incorporate it in the Suspend2 patches so it gets
some testing. I know I'd try it on my i830 based Omnibook.

Regards,

Nigel
--
Nigel Cunningham
Software Engineer, Canberra, Australia
http://www.cyclades.com

Ph: +61 (2) 6292 8028 Mob: +61 (417) 100 574