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authorJani Nikula <jani.nikula@intel.com>2022-02-03 11:03:51 +0200
committerJani Nikula <jani.nikula@intel.com>2022-02-11 11:35:37 +0200
commit0192c25c03cd2feaeaadae375fe6aadff788939a (patch)
tree9c344b7a1af0ba3d74269dcb31ad8d9894f9a999 /drivers/gpu/drm
parent0f4b58423f3500ee3e3159fbbd6c41a6e6f920d4 (diff)
drm/dp: add 128b/132b link status helpers from DP 2.0 E11
The DP 2.0 errata redefines link training. There are some new status bits, and some of the old ones need to be checked independently. Add helpers to do this. Cc: Uma Shankar <uma.shankar@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/5a46260d1f171fed46d0ab8fe4b6499abd65ce24.1643878928.git.jani.nikula@intel.com
Diffstat (limited to 'drivers/gpu/drm')
-rw-r--r--drivers/gpu/drm/drm_dp_helper.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 81c4aaee422b..4a5527cbd448 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -144,6 +144,69 @@ u8 drm_dp_get_adjust_tx_ffe_preset(const u8 link_status[DP_LINK_STATUS_SIZE],
}
EXPORT_SYMBOL(drm_dp_get_adjust_tx_ffe_preset);
+/* DP 2.0 errata for 128b/132b */
+bool drm_dp_128b132b_lane_channel_eq_done(const u8 link_status[DP_LINK_STATUS_SIZE],
+ int lane_count)
+{
+ u8 lane_align, lane_status;
+ int lane;
+
+ lane_align = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED);
+ if (!(lane_align & DP_INTERLANE_ALIGN_DONE))
+ return false;
+
+ for (lane = 0; lane < lane_count; lane++) {
+ lane_status = dp_get_lane_status(link_status, lane);
+ if (!(lane_status & DP_LANE_CHANNEL_EQ_DONE))
+ return false;
+ }
+ return true;
+}
+EXPORT_SYMBOL(drm_dp_128b132b_lane_channel_eq_done);
+
+/* DP 2.0 errata for 128b/132b */
+bool drm_dp_128b132b_lane_symbol_locked(const u8 link_status[DP_LINK_STATUS_SIZE],
+ int lane_count)
+{
+ u8 lane_status;
+ int lane;
+
+ for (lane = 0; lane < lane_count; lane++) {
+ lane_status = dp_get_lane_status(link_status, lane);
+ if (!(lane_status & DP_LANE_SYMBOL_LOCKED))
+ return false;
+ }
+ return true;
+}
+EXPORT_SYMBOL(drm_dp_128b132b_lane_symbol_locked);
+
+/* DP 2.0 errata for 128b/132b */
+bool drm_dp_128b132b_eq_interlane_align_done(const u8 link_status[DP_LINK_STATUS_SIZE])
+{
+ u8 status = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED);
+
+ return status & DP_128B132B_DPRX_EQ_INTERLANE_ALIGN_DONE;
+}
+EXPORT_SYMBOL(drm_dp_128b132b_eq_interlane_align_done);
+
+/* DP 2.0 errata for 128b/132b */
+bool drm_dp_128b132b_cds_interlane_align_done(const u8 link_status[DP_LINK_STATUS_SIZE])
+{
+ u8 status = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED);
+
+ return status & DP_128B132B_DPRX_CDS_INTERLANE_ALIGN_DONE;
+}
+EXPORT_SYMBOL(drm_dp_128b132b_cds_interlane_align_done);
+
+/* DP 2.0 errata for 128b/132b */
+bool drm_dp_128b132b_link_training_failed(const u8 link_status[DP_LINK_STATUS_SIZE])
+{
+ u8 status = dp_link_status(link_status, DP_LANE_ALIGN_STATUS_UPDATED);
+
+ return status & DP_128B132B_LT_FAILED;
+}
+EXPORT_SYMBOL(drm_dp_128b132b_link_training_failed);
+
u8 drm_dp_get_adjust_request_post_cursor(const u8 link_status[DP_LINK_STATUS_SIZE],
unsigned int lane)
{