drm/dp: reuse the 8b/10b link training delay helpers

Reuse the 8b/10b link training delay helpers. Functionally this skips
the check for invalid values for DPCD 1.4 and later at clock recovery
delay (as it's a fixed delay and bypasses the rd_interval) but the same
value will be checked and invalid values reported at channel
equalization.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014150059.28957-2-jani.nikula@intel.com

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index c5d15ac..3b46eb3 100644 (file)
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -270,35 +270,25 @@ EXPORT_SYMBOL(drm_dp_read_channel_eq_delay);
 void drm_dp_link_train_clock_recovery_delay(const struct drm_dp_aux *aux,
                                            const u8 dpcd[DP_RECEIVER_CAP_SIZE])
 {
-       unsigned long rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
-                                        DP_TRAINING_AUX_RD_MASK;
+       u8 rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
+               DP_TRAINING_AUX_RD_MASK;
+       int delay_us;
 
-       if (rd_interval > 4)
-               drm_dbg_kms(aux->drm_dev, "%s: AUX interval %lu, out of range (max 4)\n",
-                           aux->name, rd_interval);
-
-       if (rd_interval == 0 || dpcd[DP_DPCD_REV] >= DP_DPCD_REV_14)
-               rd_interval = 100;
+       if (dpcd[DP_DPCD_REV] >= DP_DPCD_REV_14)
+               delay_us = 100;
        else
-               rd_interval *= 4 * USEC_PER_MSEC;
+               delay_us = __8b10b_clock_recovery_delay_us(aux, rd_interval);
 
-       usleep_range(rd_interval, rd_interval * 2);
+       usleep_range(delay_us, delay_us * 2);
 }
 EXPORT_SYMBOL(drm_dp_link_train_clock_recovery_delay);
 
 static void __drm_dp_link_train_channel_eq_delay(const struct drm_dp_aux *aux,
-                                                unsigned long rd_interval)
+                                                u8 rd_interval)
 {
-       if (rd_interval > 4)
-               drm_dbg_kms(aux->drm_dev, "%s: AUX interval %lu, out of range (max 4)\n",
-                           aux->name, rd_interval);
-
-       if (rd_interval == 0)
-               rd_interval = 400;
-       else
-               rd_interval *= 4 * USEC_PER_MSEC;
+       int delay_us = __8b10b_channel_eq_delay_us(aux, rd_interval);
 
-       usleep_range(rd_interval, rd_interval * 2);
+       usleep_range(delay_us, delay_us * 2);
 }
 
 void drm_dp_link_train_channel_eq_delay(const struct drm_dp_aux *aux,