[Intel-gfx] [PATCH v2 5/9] drm/i915/psr: Handle PSR RFB storage error

[Souza, Jose]

On Thu, 2018-04-26 at 15:37 -0700, Dhinakaran Pandiyan wrote:
> 
> 
> On Wed, 2018-04-18 at 15:43 -0700, José Roberto de Souza wrote:
> > Sink will interrupt source when it have any problem saving or
> > reading
> > the remote frame buffer.
> > 
> > Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> > Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> > Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > ---
> > 
> > Changes from v1:
> > - printing a debug message when sink assert a error
> > 
> >  drivers/gpu/drm/i915/intel_psr.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_psr.c
> > b/drivers/gpu/drm/i915/intel_psr.c
> > index 4cb27faab707..558b08a43f9e 100644
> > --- a/drivers/gpu/drm/i915/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/intel_psr.c
> > @@ -1156,6 +1156,18 @@ void intel_psr_hpd_short_pulse_handle(struct
> > intel_dp *intel_dp)
> >  		intel_psr_exit(dev_priv);
> >  	}
> >  
> > +	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PSR_ERROR_STATUS,
> > &val) != 1) {
> > +		DRM_DEBUG_KMS("PSR_ERROR_STATUS read failed\n");
> > +		goto dpcd_error;
> > +	}
> > +
> > +	if (val & DP_PSR_RFB_STORAGE_ERROR) {
> > +		DRM_DEBUG_KMS("PSR RFB storage error, exiting
> > PSR\n");
> > +		intel_psr_exit(dev_priv);
> 
> What do we achieve with an exit? Resetting PSR? I don't think that's
> enough if the sink has storage errors. I think we should just disable
> PSR here too.

Disabling now.

> 
> > +	}
> > +	/* clear status register */
> > +	drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_ERROR_STATUS,
> > val);
> 
> So the other two errors are not handled, silently clearing them isn't
> right. How about at least printing a debug with the read value and
> saying the error wasn't handled?

DP_PSR_VSC_SDP_UNCORRECTABLE_ERROR is only applicable for PSR2 and to
sink report DP_PSR_LINK_CRC_ERROR a bit needs to be set in
DP_PSR_EN_CFG(both done in the next patch).

Do you still think that would be nice to print?

> 
> > +
> >  	/* TODO: handle other PSR/PSR2 errors */
> >  dpcd_error:
> >  	intel_psr_schedule_activate_work(dev_priv);
> 
>