drm/i915/dp: centralize max source rate conditions more

Turn intel_dp_source_supports_hbr2() into a simple helper to query the
pre-filled source rates array, and move the conditions about which
platforms support which rates to the single point of truth in
intel_dp_set_source_rates().

This also reduces the code paths you have to think about in the source
rates initialization in intel_dp_set_source_rates(), making it easier to
grasp.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009092959.29021-2-jani.nikula@intel.com

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index ca48bce23a6f1e2795e29184a22d1053217ebf08..09d75df497c09e656def6166e4bcec7ec6d671c1 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -254,15 +254,15 @@ intel_dp_set_source_rates(struct intel_dp *intel_dp)
        } else if (IS_GEN9_BC(dev_priv)) {
                source_rates = skl_rates;
                size = ARRAY_SIZE(skl_rates);
-       } else {
+       } else if ((IS_HASWELL(dev_priv) && !IS_HSW_ULX(dev_priv)) ||
+                  IS_BROADWELL(dev_priv)) {
                source_rates = default_rates;
                size = ARRAY_SIZE(default_rates);
+       } else {
+               source_rates = default_rates;
+               size = ARRAY_SIZE(default_rates) - 1;
        }
 
-       /* This depends on the fact that 5.4 is last value in the array */
-       if (!intel_dp_source_supports_hbr2(intel_dp))
-               size--;
-
        intel_dp->source_rates = source_rates;
        intel_dp->num_source_rates = size;
 }
@@ -1482,14 +1482,9 @@ intel_dp_aux_init(struct intel_dp *intel_dp)
 
 bool intel_dp_source_supports_hbr2(struct intel_dp *intel_dp)
 {
-       struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
-       struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
+       int max_rate = intel_dp->source_rates[intel_dp->num_source_rates - 1];
 
-       if ((IS_HASWELL(dev_priv) && !IS_HSW_ULX(dev_priv)) ||
-           IS_BROADWELL(dev_priv) || (INTEL_GEN(dev_priv) >= 9))
-               return true;
-       else
-               return false;
+       return max_rate >= 540000;
 }
 
 static void