[Nouveau] [PATCH] drm/nouveau: fix early vram corruption originating from vgacon

[Marcin Slusarz]

On Thu, Oct 04, 2012 at 01:44:13PM +0200, Marcin Kościelnicki wrote:
> On 04.10.2012 13:35, Marcin Slusarz wrote:
> > On Thu, Sep 13, 2012 at 12:52:30AM +0200, Marcin Slusarz wrote:
> This (and corresponding unload line) is a bug: you should NOT blindly 
> set this register to 1 on unload, use its previous value instead. 
> Otherwise you can get into sticky situations involving two GPUs 
> responding to VGA address space. Better yet, think up a proper solution 
> involving vga arb.

Thanks to your comment I noticed two more things:
- I probably should have used dword API variant.
- There is already code in nouveau which bashes this register (nouveau_vga.c /
nouveau_vga_set_decode) and it's wired to vgaarb. It seems it's set to 0 only
when there is more than one card. I'm not sure how to handle it yet...

Marcin