[Intel-gfx] [PATCH] drm: i915: Fix audio issue on BXT

Tue Feb 27 17:30:40 UTC 2018

Ok, please update the workaround page to show all the impacted projects
https://gfxspecs.intel.com/Predator/Home/Index/21829


> -----Original Message-----
> From: Mullah, Abid A
> Sent: Tuesday, 27 February, 2018 8:52 AM
> To: Runyan, Arthur J <arthur.j.runyan at intel.com>; Pandiyan, Dhinakaran
> <dhinakaran.pandiyan at intel.com>; Singh, Gaurav K
> <gaurav.k.singh at intel.com>; Neelagandan, Harigaran
> <harigaran.neelagandan at intel.com>
> Cc: intel-gfx at lists.freedesktop.org; Vivi, Rodrigo <rodrigo.vivi at intel.com>;
> Nikula, Jani <jani.nikula at intel.com>
> Subject: RE: [Intel-gfx] [PATCH] drm: i915: Fix audio issue on BXT
> 
> Yes. It will be needed for BXT also.
> 
> -----Original Message-----
> From: Runyan, Arthur J
> Sent: Tuesday, February 27, 2018 8:49 AM
> To: Pandiyan, Dhinakaran <dhinakaran.pandiyan at intel.com>; Singh, Gaurav
> K <gaurav.k.singh at intel.com>; Mullah, Abid A <abid.a.mullah at intel.com>;
> Neelagandan, Harigaran <harigaran.neelagandan at intel.com>
> Cc: intel-gfx at lists.freedesktop.org; Vivi, Rodrigo <rodrigo.vivi at intel.com>;
> Nikula, Jani <jani.nikula at intel.com>
> Subject: RE: [Intel-gfx] [PATCH] drm: i915: Fix audio issue on BXT
> 
> Abid or Hari, please check.  There was a workaround to set
> AUD_CHICKENBIT_REG bit 15 (Codec Wake overwrite to DACFEUNIT) on SKL
> and KBL.  Does it apply to BXT also?
> 
> > -----Original Message-----
> > From: Pandiyan, Dhinakaran
> > Sent: Monday, 26 February, 2018 6:04 PM
> > To: Runyan, Arthur J <arthur.j.runyan at intel.com>; Singh, Gaurav K
> > <gaurav.k.singh at intel.com>
> > Cc: intel-gfx at lists.freedesktop.org; Vivi, Rodrigo
> > <rodrigo.vivi at intel.com>; Nikula, Jani <jani.nikula at intel.com>
> > Subject: RE: [Intel-gfx] [PATCH] drm: i915: Fix audio issue on BXT
> >
> >
> > > -----Original Message-----
> > > From: Runyan, Arthur J
> > > Sent: Tuesday, January 9, 2018 11:55 AM
> > > To: Pandiyan, Dhinakaran <dhinakaran.pandiyan at intel.com>; Singh,
> > Gaurav K
> > > <gaurav.k.singh at intel.com>
> > > Cc: intel-gfx at lists.freedesktop.org; Vivi, Rodrigo
> > > <rodrigo.vivi at intel.com>
> > > Subject: RE: [Intel-gfx] [PATCH] drm: i915: Fix audio issue on BXT
> > >
> > > Sorry, I've been out.  I'm checking on this.
> >
> >
> > Hi Art,
> >
> > Is AUD_CHICKENBIT_REG:15 needed for BXT to fix code enumeration
> issues?
> >
> > -DK
> >
> > >
> > > -----Original Message-----
> > > From: Pandiyan, Dhinakaran
> > > Sent: Thursday, 4 January, 2018 2:00 PM
> > > To: Singh, Gaurav K <gaurav.k.singh at intel.com>
> > > Cc: intel-gfx at lists.freedesktop.org; Vivi, Rodrigo
> > > <rodrigo.vivi at intel.com>; subransu.s.prusty at intel.com; Runyan,
> > > Arthur J
> > <arthur.j.runyan at intel.com>
> > > Subject: Re: [Intel-gfx] [PATCH] drm: i915: Fix audio issue on BXT
> > >
> > > +Art
> > >
> > > On Thu, 2018-01-04 at 22:13 +0530, Singh, Gaurav K wrote:
> > > >
> > > > On 1/4/2018 2:48 AM, Rodrigo Vivi wrote:
> > > > > On Wed, Jan 03, 2018 at 08:31:10PM +0000, Pandiyan, Dhinakaran
> > wrote:
> > > > >> On Thu, 2018-01-04 at 00:48 +0530, Gaurav K Singh wrote:
> > > > >>> From: Gaurav Singh <gaurav.k.singh at intel.com>
> > > > >>>
> > > > >>> On Apollolake, with stress test warm reboot, audio card was
> > > > >>> not getting enumerated after reboot. This was a
> > > > >> The problem looks similar to
> > > > >> https://lists.freedesktop.org/archives/intel-gfx/2017-October/1
> > > > >> 4449
> > > > >> 5.html
> > > > >>
> > > > >> although the proposed solutions are vastly different. I have
> > > > >> Cc'd some more people.
> > > > >>
> > > > >>> spurious issue happening on Apollolake. HW codec and HD audio
> > > > >>> controller link was going out of sync for which there was a
> > > > >>> fix in
> > > > >>> i915 driver but was not getting invoked for BXT. Extending
> > > > >>> this fix to BXT as well.
> > > > >>>
> > > > >>> Tested on apollolake chromebook by stress test warm reboot
> > > > >>> with
> > > > >>> 2500 iterations.
> > > > >>>
> > > > >>> Signed-off-by: Gaurav K Singh <gaurav.k.singh at intel.com>
> > > > >>> ---
> > > > >>>   drivers/gpu/drm/i915/intel_audio.c | 2 +-
> > > > >>>   1 file changed, 1 insertion(+), 1 deletion(-)
> > > > >>>
> > > > >>> diff --git a/drivers/gpu/drm/i915/intel_audio.c
> > > > >>> b/drivers/gpu/drm/i915/intel_audio.c
> > > > >>> index f1502a0188eb..c71c04e1c3f6 100644
> > > > >>> --- a/drivers/gpu/drm/i915/intel_audio.c
> > > > >>> +++ b/drivers/gpu/drm/i915/intel_audio.c
> > > > >>> @@ -729,7 +729,7 @@ static void
> > > i915_audio_component_codec_wake_override(struct device *kdev,
> > > > >>>   	struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
> > > > >>>   	u32 tmp;
> > > > >>>
> > > > >>> -	if (!IS_GEN9_BC(dev_priv))
> > > > >>> +	if (!IS_GEN9_BC(dev_priv) && !IS_BROXTON(dev_priv))
> > > > >> IS_GEN9()? GLK might need this too.
> > > > > I think this is applicable for all Gen9 platforms.
> > > >
> > > > > if GLK need there is the possibility of CNL also needing it...
> > > > > So not sure where to stop.
> > > > >
> > > > > Also looking to the original patch that introduced this
> > > > > function, commit '632f3ab95fe2 ("drm/i915/audio: add codec
> > > > > wakeup override enabled/disable callback")'
> > > > >
> > > > > it tells that the reason was:
> > > > > "In SKL, HDMI/DP codec and PCH HD Audio Controller are in
> > > > > different p$ wells, so it's necessary to reset display audio
> > > > > codecs when power we$ otherwise display audio codecs will
> > > > > disappear when resume from low p$ state."
> > > > >
> > > > > Is this the case here on BXT?
> > > > Yes, its the same case with BXT.
> > > > >
> > > > > Another interesting thing I noticed on Spec when searching for
> > > > > this bit was that this bit is related to an workaround on SKL/KBL/CFL...
> > > > > no mention to BXT.
> > > > >
> > > > > "This workaround is needed for an HW issue in SKL and KBL in
> > > > > which HW codec and HD audio controller link was going out of sync."
> > > > Yes, in Bspec it has been mentioned only for SKL and KBL. But
> > > > without this fix, sound card was not getting enumerated for BXT.
> > >
> > >
> > > Art,
> > >
> > > Can you please help us here? To summarize, the question is what
> > > platforms
> > need
> > > the AUD_CHICKENBIT_REG:15 bit to be set to avoid code enumeration
> > failures?
> > >
> > > -DK
> > >
> > > > >
> > > > > Thanks,
> > > > > Rodrigo.
> > > > >
> > > > >>
> > > > >>>   		return;
> > > > >>>
> > > > >>>   	i915_audio_component_get_power(kdev);
> > > > >> _______________________________________________
> > > > >> Intel-gfx mailing list
> > > > >> Intel-gfx at lists.freedesktop.org
> > > > >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> > > >