Re: Linux 2.6.37-rc8 (no fb)

["François Valenduc" <francois.valenduc@tvcablenet.be>]

Le 29/12/10 21:16, Jesse Barnes a écrit :
> On Wed, 29 Dec 2010 11:40:04 -0800
> Linus Torvalds <torvalds@linux-foundation.org> wrote:
> 
>> On Wed, Dec 29, 2010 at 10:21 AM, Randy Dunlap <randy.dunlap@oracle.com> wrote:
>>>
>>> The only significant difference that I can see in the kernel message log
>>> is this:
>>
>> Hmm. I suspect that difference should have gone away with commit
>> 92971021c6328 (Revert "drm: Don't try and disable an encoder that was
>> never enabled"), but clearly that didn't fix your blank screen.
>>
>> Does reverting commit 448f53a1ede54eb854d036abf54573281412d650
>> ("drm/i915/bios: Reverse order of 100/120 Mhz SSC clocks") fix it for
>> you? It does for some people..
>>
>> Chris - why did that lvds_ssc_freq thing suddenly start mattering? Can
>> we please just disable spread-spectrum entirely? Or perhaps only if we
>> notice that it was enabled already? Or something?
> 
> Randy, Jeff and Alex, does the below help at all?  If so, it may be the
> minimal fix we want for 2.6.37.
> 
> diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios
> index 2b20786..d27d016 100644
> --- a/drivers/gpu/drm/i915/intel_bios.c
> +++ b/drivers/gpu/drm/i915/intel_bios.c
> @@ -263,6 +263,9 @@ parse_general_features(struct drm_i915_private *dev_priv,
>                 dev_priv->int_tv_support = general->int_tv_support;
>                 dev_priv->int_crt_support = general->int_crt_support;
>                 dev_priv->lvds_use_ssc = general->enable_ssc;
> +               /* force disable until we can parse this correctly */
> +               if (IS_GEN5(dev) || IS_GEN6(dev))
> +                       dev_priv->lvds_use_ssc = 0;
>  
>                 if (dev_priv->lvds_use_ssc) {
>                         if (IS_I85X(dev))
> 
> 
I also encountered the black screen problem after commit 448f53a1. I can
confirm that the above patch solves the problem.

François Valenduc