From 363c31787344f240b7cef68ec2734665ec292f7e Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Tue, 20 Feb 2024 23:18:29 +0200 Subject: drm/i915/dp: Factor out intel_dp_read_dprx_caps() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Factor out a function to read the sink's DPRX capabilities used by a follow-up patch enabling the DP tunnel BW allocation mode. Reviewed-by: Uma Shankar Reviewed-by: Ville Syrjälä Signed-off-by: Imre Deak Link: https://patchwork.freedesktop.org/patch/msgid/20240220211841.448846-10-imre.deak@intel.com --- .../gpu/drm/i915/display/intel_dp_link_training.c | 30 ++++++++++++++++++---- 1 file changed, 25 insertions(+), 5 deletions(-) (limited to 'drivers/gpu/drm/i915/display/intel_dp_link_training.c') 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 7b140cbf8dd3..fb84ca98bb7a 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -162,6 +162,28 @@ static int intel_dp_init_lttpr(struct intel_dp *intel_dp, const u8 dpcd[DP_RECEI return lttpr_count; } +int intel_dp_read_dprx_caps(struct intel_dp *intel_dp, u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + + if (intel_dp_is_edp(intel_dp)) + return 0; + + /* + * Detecting LTTPRs must be avoided on platforms with an AUX timeout + * period < 3.2ms. (see DP Standard v2.0, 2.11.2, 3.6.6.1). + */ + if (DISPLAY_VER(i915) >= 10 && !IS_GEMINILAKE(i915)) + if (drm_dp_dpcd_probe(&intel_dp->aux, + DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV)) + return -EIO; + + if (drm_dp_read_dpcd_caps(&intel_dp->aux, dpcd)) + return -EIO; + + return 0; +} + /** * intel_dp_init_lttpr_and_dprx_caps - detect LTTPR and DPRX caps, init the LTTPR link training mode * @intel_dp: Intel DP struct @@ -192,12 +214,10 @@ int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp) if (!intel_dp_is_edp(intel_dp) && (DISPLAY_VER(i915) >= 10 && !IS_GEMINILAKE(i915))) { u8 dpcd[DP_RECEIVER_CAP_SIZE]; + int err = intel_dp_read_dprx_caps(intel_dp, dpcd); - if (drm_dp_dpcd_probe(&intel_dp->aux, DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV)) - return -EIO; - - if (drm_dp_read_dpcd_caps(&intel_dp->aux, dpcd)) - return -EIO; + if (err != 0) + return err; lttpr_count = intel_dp_init_lttpr(intel_dp, dpcd); } -- cgit v1.2.3