[Intel-gfx] [PATCH] honor VBIOS SSC & TV settings

[Jesse Barnes]

On Thursday, June 26, 2008 9:36 am Jesse Barnes wrote:
> I've been doing some work lately to use more of the VBIOS settings where
> possible.  This patch adds support for using the VBIOS for TV connector
> detection and SSC information.  On my T61 at least, using this patch keeps
> me from having to use the T61 TV ignore quirk.
>
> SSC (spread spectrum clock) is a EMI reducing feature 855+ chips support. 
> It allows the OEM to provide an external reference clock and connect it to
> the GPU to modulate the display clock frequency.  Since it requires an
> external part, information about its presence and frequency is supposed to
> be in the VBIOS general info block.
>
> I'm not sure how accurate the VBIOS info is for either TV or SSC info, so
> I'd like to get some feedback.  Can people give this a try?  It disables
> the TV quirk logic, so it'll rely on the VBIOS for getting TV output
> presence info. And it will unconditionally use SSC if it finds it, so
> you'll see a message like
> (II) intel(0): using SSC reference clock of 100 MHz
> in your log if it ends up getting used.
>
> Please provide testing feedback on both features as a reply to this
> message.

Oh and the patch. :)

Jesse
-------------- next part --------------
A non-text attachment was scrubbed...
Name: i830-vbios-features.patch
Type: text/x-diff
Size: 8191 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/intel-gfx/attachments/20080626/693d9b11/attachment.patch>