From bf039fa9357bdd26b3f115efd8af527523212069 Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Fri, 5 Feb 2016 12:16:09 +0200 Subject: [PATCH] drm/i915/dp: abstract training pattern selection Make it cleaner to add more checks in the function. No functional changes. Cc: Ander Conselvan de Oliveira Cc: Sivakumar Thulasimani Reviewed-by: Sivakumar Thulasimani Cc: drm-intel-fixes@lists.freedesktop.org # dependency on the next patch Signed-off-by: Jani Nikula Link: http://patchwork.freedesktop.org/patch/msgid/1454667370-8001-1-git-send-email-jani.nikula@intel.com (cherry picked from commit 23a5110dc619073b57d90c36eae383f51df03aac) Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/intel_dp_link_training.c | 25 +++++++++++++------ 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp_link_training.c b/drivers/gpu/drm/i915/intel_dp_link_training.c index 88887938e0bf..83e667b92fda 100644 --- a/drivers/gpu/drm/i915/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/intel_dp_link_training.c @@ -215,16 +215,15 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp) } } -static void -intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) +/* + * Pick training pattern for channel equalization. Training Pattern 3 for HBR2 + * or 1.2 devices that support it, Training Pattern 2 otherwise. + */ +static u32 intel_dp_training_pattern(struct intel_dp *intel_dp) { - bool channel_eq = false; - int tries, cr_tries; - uint32_t training_pattern = DP_TRAINING_PATTERN_2; + u32 training_pattern = DP_TRAINING_PATTERN_2; /* - * Training Pattern 3 for HBR2 or 1.2 devices that support it. - * * Intel platforms that support HBR2 also support TPS3. TPS3 support is * also mandatory for downstream devices that support HBR2. * @@ -237,6 +236,18 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) else if (intel_dp->link_rate == 540000) DRM_ERROR("5.4 Gbps link rate without HBR2/TPS3 support\n"); + return training_pattern; +} + +static void +intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) +{ + bool channel_eq = false; + int tries, cr_tries; + u32 training_pattern; + + training_pattern = intel_dp_training_pattern(intel_dp); + /* channel equalization */ if (!intel_dp_set_link_train(intel_dp, training_pattern | -- 2.30.2