[PATCH 3/3] drm/radeon/kms: enable writeback on remaing asics

[Alex Deucher]

2010/8/27 Michel Dänzer <michel at daenzer.net>:
> On Fre, 2010-08-06 at 21:37 -0400, Alex Deucher wrote:
>> This enables writeback for the CP read pointer and
>> scratch regs on the remaining radeon asics.
>
> This doesn't work on my PowerBook. AFAIR the CP writeback isn't reliable
> with at least older Apple AGP bridges and probably others as well, which
> is why in the non-KMS case we're using the direct PCI bus address
> instead of a GTT address.
>

I'm not sure it's worth the effort to try and fix this up with kms for
older AGP asics especially since we don't pass through addresses
directly anymore in the MC setup.  Maybe just disable wb on AGP cards
by default.

Alex

>
> --
> Earthling Michel Dänzer           |                http://www.vmware.com
> Libre software enthusiast         |          Debian, X and DRI developer
>