> -----Original Message-----
> From: Intel-gfx <intel-gfx-boun...@lists.freedesktop.org> On Behalf Of Jani
> Nikula
> Sent: Wednesday, January 12, 2022 4:33 PM
> To: intel-gfx@lists.freedesktop.org
> Cc: Nikula, Jani <jani.nik...@intel.com>
> Subject: [Intel-gfx] [PATCH RESEND 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
> back to the original DP MST enabling. Keep it, though I have no idea why we
> have it.
Reviewed-by: Uma Shankar <uma.shan...@intel.com>
> Signed-off-by: Jani Nikula <jani.nik...@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 e789ecbc69f3..a301220ce2ad 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2821,6 +2821,19 @@ 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) @@ -3661,7
> +3674,6 @@ 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,
> @@ -3686,15 +3698,8 @@ 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
