[Intel-gfx] [PATCH] drm/i915/display/fbc: Disable fbc by default on TGL

[Shankar, Uma]

> -----Original Message-----
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Sent: Thursday, July 16, 2020 6:19 PM
> To: Shankar, Uma <uma.shankar at intel.com>
> Cc: intel-gfx at lists.freedesktop.org
> Subject: Re: [Intel-gfx] [PATCH] drm/i915/display/fbc: Disable fbc by default on
> TGL
> 
> On Thu, Jul 16, 2020 at 03:38:03PM +0300, Ville Syrjälä wrote:
> > On Thu, Jul 16, 2020 at 02:25:40PM +0530, Uma Shankar wrote:
> > > Fbc is causing random underruns in CI execution on TGL platforms.
> > > Disabling the same while the problem is being debugged and analyzed.
> > >
> > > Cc: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
> > > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> >
> > Acked-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Scratch that...
> 
> >
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_fbc.c | 7 +++++++
> > >  1 file changed, 7 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c
> > > b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > index 3a4f980788a6..1d6370b29b27 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > > @@ -1420,6 +1420,13 @@ void intel_fbc_handle_fifo_underrun_irq(struct
> drm_i915_private *dev_priv)
> > >   */
> > >  static int intel_sanitize_fbc_option(struct drm_i915_private
> > > *dev_priv)  {
> > > +	/*
> > > +	 * Fbc is causing random underruns in CI execution on TGL platforms.
> > > +	 * Disabling the same while the problem is being debugged and analyzed.
> > > +	 */
> > > +	if (IS_TIGERLAKE(dev_priv))
> > > +		return 0;
> 
> ... looks lke this should be done *after* the modparam check below.
> Otherwise we can't enable fbc for testing via the modparam.

Oh yeah, updated the change and sent a v2 with fix. Thanks Ville.

Regards,
Uma Shankar

> > > +
> > >  	if (dev_priv->params.enable_fbc >= 0)
> > >  		return !!dev_priv->params.enable_fbc;
> > >
> > > --
> > > 2.22.0
> >
> > --
> > Ville Syrjälä
> > Intel
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> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> --
> Ville Syrjälä
> Intel