Re: [Intel-gfx] [PATCH 2/7] drm/i915/mst: abstract intel_dp_ack_sink_irq_esi()

["Shankar, Uma" <uma.shankar@intel.com>]

> -----Original Message-----
> From: Nikula, Jani <jani.nikula@intel.com>
> Sent: Thursday, January 20, 2022 4:02 PM
> To: Shankar, Uma <uma.shankar@intel.com>; intel-gfx@lists.freedesktop.org
> Subject: RE: [Intel-gfx] [PATCH 2/7] drm/i915/mst: abstract
> intel_dp_ack_sink_irq_esi()
> 
> On Thu, 20 Jan 2022, "Shankar, Uma" <uma.shankar@intel.com> wrote:
> >> -----Original Message-----
> >> From: Intel-gfx <intel-gfx-bounces@lists.freedesktop.org> On Behalf Of Jani
> Nikula
> >> Sent: Tuesday, January 4, 2022 11:10 PM
> >> To: intel-gfx@lists.freedesktop.org
> >> Cc: Nikula, Jani <jani.nikula@intel.com>
> >> Subject: [Intel-gfx] [PATCH 2/7] drm/i915/mst: abstract
> intel_dp_ack_sink_irq_esi()
> >>
> >> Smaller functions make the thing easier to read. Debug log failures to ack.
> >>
> >> Note: Looks like we have the retry loop simply because of hysterical raisins,
> dating
> >
> > Nit: Typo in reasons.
> 
> ;)
> 
> http://www.catb.org/jargon/html/H/hysterical-reasons.html

Oh, didn't knew that 😊. A new phrase in vocabulary 😝

> >
> > Reviewed-by: Uma Shankar <uma.shankar@intel.com>
> >
> >> back to the original DP MST enabling. Keep it, though I have no idea why we have
> it.
> >>
> >> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> >> ---
> >>  drivers/gpu/drm/i915/display/intel_dp.c | 25 +++++++++++++++----------
> >>  1 file changed, 15 insertions(+), 10 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> >> b/drivers/gpu/drm/i915/display/intel_dp.c
> >> index 357c39e09bf6..ebf80a875a41 100644
> >> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> >> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> >> @@ -2820,6 +2820,19 @@ intel_dp_get_sink_irq_esi(struct intel_dp *intel_dp,
> u8
> >> *sink_irq_vector)
> >>  		DP_DPRX_ESI_LEN;
> >>  }
> >>
> >> +static bool intel_dp_ack_sink_irq_esi(struct intel_dp *intel_dp, u8
> >> +esi[4]) {
> >> +	int retry;
> >> +
> >> +	for (retry = 0; retry < 3; retry++) {
> >> +		if (drm_dp_dpcd_write(&intel_dp->aux, DP_SINK_COUNT_ESI + 1,
> >> +				      &esi[1], 3) == 3)
> >> +			return true;
> >> +	}
> >> +
> >> +	return false;
> >> +}
> >> +
> >>  bool
> >>  intel_dp_needs_vsc_sdp(const struct intel_crtc_state *crtc_state,
> >>  		       const struct drm_connector_state *conn_state) @@ -3660,7
> >> +3673,6 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
> >>  		 */
> >>  		u8 esi[DP_DPRX_ESI_LEN+2] = {};
> >>  		bool handled;
> >> -		int retry;
> >>
> >>  		if (!intel_dp_get_sink_irq_esi(intel_dp, esi)) {
> >>  			drm_dbg_kms(&i915->drm,
> >> @@ -3685,15 +3697,8 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
> >>  		if (!handled)
> >>  			break;
> >>
> >> -		for (retry = 0; retry < 3; retry++) {
> >> -			int wret;
> >> -
> >> -			wret = drm_dp_dpcd_write(&intel_dp->aux,
> >> -						 DP_SINK_COUNT_ESI+1,
> >> -						 &esi[1], 3);
> >> -			if (wret == 3)
> >> -				break;
> >> -		}
> >> +		if (!intel_dp_ack_sink_irq_esi(intel_dp, esi))
> >> +			drm_dbg_kms(&i915->drm, "Failed to ack ESI\n");
> >>  	}
> >>
> >>  	return link_ok;
> >> --
> >> 2.30.2
> >
> 
> --
> Jani Nikula, Intel Open Source Graphics Center