[Debian-eeepc-devel] 1024x600 console [was: Re: Video out toggling]

[Phil Endecott]

Phil Endecott wrote:
> - I am very keen to get external monitor switching working for the 
> console.  Also I'd like to get a 1024x600 console, which I think needs 
> either a BIOS fix or some serious surgery in the intelfb driver.  If 
> anyone knows anything at all about this, _please_ get in touch!

I have made some progress with this.  The intelfb framebuffer driver 
doesn't support mode changing except for the VGA output.  However, the 
uvesafb framebuffer driver does as long as the mode you want is known 
to the BIOS.  But the Eee BIOS doesn't know about the panel's native 
resolution.  This can be fixed using a utility called 915resolution, 
which hacks the RAM copy of the BIOS.  But 915resolution doesn't know 
about the 945GME chip in the '901.

So, first here's a patch to 915resolution that adds support for the 
945GE chip:

   http://chezphil.org/tmp/915r_945GME.patch

(I've sent this to the 915resolution maintainer.  Does anyone know 
about the status of 915resolution in Debian?)

You can now replace a mode that you're not interested in with the 
native resolution, e.g.

# 915resolution 34 1024 600

Now load uvesafb:

# modprobe uvesafb

It will now report 1024x600 modes in 
/sys/devices/platform/uvesafb.0/vbe_modes.  You also need a 1024x600 
entry in /etc/fb.modes, e.g.

mode "1024x600-60"
     geometry 1024 600 1024 600 8
     timings 20461 144 40 18 1 104 3
endmode

You can now switch to this mode:

# fbset 1024x600-60

You should now have a 1024x600-pixel console, and (e.g.) DirectFB 
applications should be able to take advantage of it.

I'm not yet sure how best to do all of this during boot; any Debian 
boot experts out there?


The trouble with this solution is that it only works with uvesafb, not 
with intelfb.  To work with intelfb I think the BIOS hacking would need 
to happen before the kernel starts (or at least before intelfb starts); 
I have seen some notes about integrating the 915resolution 
functionality into GRUB in order to make this possible.  And there's 
still no way to do output switching.

I hope this is of interest to someone.  Would any of the Eee-using 
Debian Devs on this list like to check on the status of the 
915resolution package?  It could be useful to a few people around here 
I guess....


Cheers,  Phil.