On Thu, 2025-07-03 at 16:14 +0300, Imre Deak wrote: > On Thu, Jul 03, 2025 at 04:02:18PM +0300, Luca Coelho wrote: > > On Thu, 2025-06-26 at 11:20 +0300, Imre Deak wrote: > > > From: Imre Deak <imre.d...@gmail.com> > > > > > > Read and ack the sink count, sink device and link service IRQs for SST > > > the same way this is done for MST, the read/ack happening in separate > > > steps via an ESI (Event Status Indicator) vector. > > > > > > The above way is more efficient, since on newer (DPCD_REV >= 1.2) sinks > > > the DP_SINK_COUNT_ESI..DP_LINK_SERVICE_IRQ_VECTOR_ESI0 registers can be > > > read out in one AUX transaction - and the 3 last one written in one > > > transaction. Also this allows sharing more of the SST and MST IRQ > > > handling code (done as a follow-up). > > > > > > For now keep the current behavior of always reading the legacy > > > DP_SINK_COUNT, DP_DEVICE_SERVICE_IRQ_VECTOR registers and not reading > > > the DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1 register. > > > > > > Signed-off-by: Imre Deak <imre.d...@gmail.com> > > > --- > > > drivers/gpu/drm/i915/display/intel_dp.c | 132 +++++++++++++----------- > > > 1 file changed, 73 insertions(+), 59 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > > > b/drivers/gpu/drm/i915/display/intel_dp.c > > > index 2ba4a810f22c2..2e6ed7d2a64a6 100644 > > > --- a/drivers/gpu/drm/i915/display/intel_dp.c > > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > > > @@ -4573,6 +4573,70 @@ static bool intel_dp_ack_sink_irq_esi(struct > > > intel_dp *intel_dp, u8 esi[4]) > > > return false; > > > } > > > > > > +static bool intel_dp_get_sink_irq_esi_sst(struct intel_dp *intel_dp, u8 > > > esi[4]) > > > +{ > > > + memset(esi, 0, 4); > > > + > > > + /* > > > + * TODO: For DP_DPCD_REV >= 0x12 read > > > + * DP_SINK_COUNT_ESI and DP_DEVICE_SERVICE_IRQ_VECTOR_ESI0. > > > + */ > > > + if (drm_dp_dpcd_read_data(&intel_dp->aux, DP_SINK_COUNT, esi, 2) != 0) > > > + return false; > > > + > > > + if (intel_dp->dpcd[DP_DPCD_REV] < DP_DPCD_REV_12) > > > + return true; > > > + > > > + /* TODO: Read DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1 as well */ > > > + if (drm_dp_dpcd_read_byte(&intel_dp->aux, > > > DP_LINK_SERVICE_IRQ_VECTOR_ESI0, &esi[3]) != 0) > > > + return false; > > > + > > > + return true; > > > +} > > > + > > > +static bool intel_dp_ack_sink_irq_esi_sst(struct intel_dp *intel_dp, u8 > > > esi[4]) > > > +{ > > > + /* > > > + * TODO: For DP_DPCD_REV >= 0x12 write > > > + * DP_DEVICE_SERVICE_IRQ_VECTOR_ESI0 > > > + */ > > > + if (drm_dp_dpcd_write_byte(&intel_dp->aux, > > > DP_DEVICE_SERVICE_IRQ_VECTOR, esi[1]) != 0) > > > + return false; > > > + > > > + if (intel_dp->dpcd[DP_DPCD_REV] < DP_DPCD_REV_12) > > > + return true; > > > + > > > + /* TODO: Read DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1 as well */ > > > + if (drm_dp_dpcd_write_byte(&intel_dp->aux, > > > DP_LINK_SERVICE_IRQ_VECTOR_ESI0, esi[3]) != 0) > > > + return false; > > > + > > > + return true; > > > +} > > > + > > > +static bool intel_dp_get_and_ack_sink_irq_esi_sst(struct intel_dp > > > *intel_dp, u8 esi[4]) > > > +{ > > > + struct intel_display *display = to_intel_display(intel_dp); > > > + struct intel_connector *connector = intel_dp->attached_connector; > > > + struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base; > > > + > > > + if (!intel_dp_get_sink_irq_esi_sst(intel_dp, esi)) > > > + return false; > > > + > > > + drm_dbg_kms(display->drm, > > > + "[CONNECTOR:%d:%s][ENCODER:%d:%s] DPRX ESI: %4ph\n", > > > + connector->base.base.id, connector->base.name, > > > + encoder->base.base.id, encoder->base.name, > > > + esi); > > > + > > > + if (mem_is_zero(&esi[1], 3)) > > > + return true; > > > + > > > + if (!intel_dp_ack_sink_irq_esi_sst(intel_dp, esi)) > > > + return false; > > > + > > > + return true; > > > +} > > > + > > > > Again, I think it's better to propagate the error than to swallow it > > and return a bool. > > I agree. But doing that would make these functions return error in > different ways than the MST > > intel_dp_get_sink_irq_esi(), intel_dp_ack_sink_irq_esi() > > functions, which return a pass/fail bool. Imo the error return should be > the same for both the SST and MST variety of functions and converting > to propagate an error instead of a pass/fail bool should be done for > both (SST and MST), which is best done as a follow-up. Are you ok with > that? >
Okay, a follow-up patch sounds good to me. -- Cheers, Luca.