i915: screen flicker

[Mihai Donțu]

On Wed, 27 Apr 2016 20:36:13 +0300 Mihai Donțu wrote:
> On Wed, 27 Apr 2016 08:28:20 -0700 Rodrigo Vivi wrote:
> > Hi Mihai,
> > 
> > What platform do you have? HSW or BDW?  
> 
> I have an i7, Haswell CPU.
> 
> > If you don't know please provide lspci -nn  
> 
> I have attached the output of lspci, just in case. :-)
> 
> > What happens if you boot with i915.enable_psr=2?  
> 
> I'll try now.

The behaviour is worse now. The screen flickers every couple of seconds.

> > In case it helps, could you please boot with default
> > i915.enable_psr=-1 appying this patch to your kernel to know what your
> > VBT recommends:
> > diff --git a/drivers/gpu/drm/i915/intel_psr.c
> > b/drivers/gpu/drm/i915/intel_psr.c
> > index c3abae4..68bc405 100644
> > --- a/drivers/gpu/drm/i915/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/intel_psr.c
> > @@ -798,6 +798,8 @@ void intel_psr_init(struct drm_device *dev)
> >                 /* For new platforms let's respect VBT back again */
> >                 dev_priv->psr.link_standby =
> > dev_priv->vbt.psr.full_link;
> > 
> > +       DRM_ERROR("PSR: VBT recommends link_standby %d, using %d\n",
> > dev_priv->vbt.psr.full_link, dev_priv->psr.link_standby);
> > +
> >         /* Override link_standby x link_off defaults */
> >         if (i915.enable_psr == 2 && !dev_priv->psr.link_standby) {
> >                 DRM_DEBUG_KMS("PSR: Forcing link standby\n");
> >   
> 
> I applied your patch and booted with enable_psr=-1
> 
> [    0.763651] [drm:intel_psr_init] *ERROR* PSR: VBT recommends link_standby 0, using 0

-- 
Mihai Donțu