> -----Original Message-----
> From: Intel-xe <intel-xe-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Arun R
> Murthy
> Sent: Thursday, September 12, 2024 10:36 AM
> To: intel-xe@xxxxxxxxxxxxxxxxxxxxx; intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Murthy, Arun R <arun.r.murthy@xxxxxxxxx>; Srikanth V, NagaVenkata
> <nagavenkata.srikanth.v@xxxxxxxxx>
> Subject: [PATCH 2/3] drm/i915/dp: read Aux RD interval after reading the FFE
> preset
>
> DP Source should be reading AUX_RD interval after we get adjusted
> TX_FFE_PRESET_VALUE from the DP Sink. (before actually adjusting in DP
> Source)
I think mentioning the dp spec reference here would be helpful
>
> Signed-off-by: Srikanth V NagaVenkata <nagavenkata.srikanth.v@xxxxxxxxx>
> Signed-off-by: Arun R Murthy <arun.r.murthy@xxxxxxxxx>
> ---
> .../gpu/drm/i915/display/intel_dp_link_training.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> index f41b69840ad9..ca179bed46ad 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> @@ -1419,12 +1419,6 @@ intel_dp_128b132b_lane_eq(struct intel_dp
> *intel_dp,
> for (try = 0; try < max_tries; try++) {
> fsleep(delay_us);
>
> - /*
> - * The delay may get updated. The transmitter shall read the
> - * delay before link status during link training.
> - */
> - delay_us =
> drm_dp_128b132b_read_aux_rd_interval(&intel_dp->aux);
> -
> if (drm_dp_dpcd_read_link_status(&intel_dp->aux,
> link_status) < 0) {
> lt_err(intel_dp, DP_PHY_DPRX, "Failed to read link
> status\n");
> return false;
> @@ -1457,6 +1451,12 @@ intel_dp_128b132b_lane_eq(struct intel_dp
> *intel_dp,
> lt_err(intel_dp, DP_PHY_DPRX, "Failed to update TX
> FFE settings\n");
> return false;
> }
> +
> + /*
> + * The delay may get updated. The transmitter shall read the
> + * delay before link status during link training.
> + */
The comment needs to be updated as this is not being done before link status
Also a question does this not conflict with the requirement we previously had (reading it before link status) ?
Regards,
Suraj Kandpal
Regards,
Suraj Kandpal
> + delay_us =
> drm_dp_128b132b_read_aux_rd_interval(&intel_dp->aux);
> }
>
> if (try == max_tries) {
> --
> 2.25.1
