drm/i915/dp: move link rate arrays where they're used

Localize link rate arrays by moving them to the functions where they're
used. Further clarify the distinction between source and sink
capabilities. Split pre and post Haswell arrays, and get rid of the
array size arithmetics. Use a direct rate value in the paranoia case of
no common rates find.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180227105911.4485-1-jani.nikula@intel.com

drivers/gpu/drm/i915/intel_dp.c

@@ -94,15 +94,6 @@ static const struct dp_link_dpll chv_dpll[] = {
 		{ .p1 = 2, .p2 = 1, .n = 1, .m1 = 2, .m2 = 0x6c00000 } }
 };
 
-static const int bxt_rates[] = { 162000, 216000, 243000, 270000,
-				  324000, 432000, 540000 };
-static const int skl_rates[] = { 162000, 216000, 270000,
-				  324000, 432000, 540000 };
-static const int cnl_rates[] = { 162000, 216000, 270000,
-				 324000, 432000, 540000,
-				 648000, 810000 };
-static const int default_rates[] = { 162000, 270000, 540000 };
-
 /**
  * intel_dp_is_edp - is the given port attached to an eDP panel (either CPU or PCH)
  * @intel_dp: DP struct
@@ -142,14 +133,17 @@ static void intel_dp_unset_edid(struct intel_dp *intel_dp);
 /* update sink rates from dpcd */
 static void intel_dp_set_sink_rates(struct intel_dp *intel_dp)
 {
+	static const int dp_rates[] = {
+		162000, 270000, 540000
+	};
 	int i, max_rate;
 
 	max_rate = drm_dp_bw_code_to_link_rate(intel_dp->dpcd[DP_MAX_LINK_RATE]);
 
-	for (i = 0; i < ARRAY_SIZE(default_rates); i++) {
-		if (default_rates[i] > max_rate)
+	for (i = 0; i < ARRAY_SIZE(dp_rates); i++) {
+		if (dp_rates[i] > max_rate)
 			break;
-		intel_dp->sink_rates[i] = default_rates[i];
+		intel_dp->sink_rates[i] = dp_rates[i];
 	}
 
 	intel_dp->num_sink_rates = i;
@@ -266,6 +260,22 @@ static int cnl_max_source_rate(struct intel_dp *intel_dp)
 static void
 intel_dp_set_source_rates(struct intel_dp *intel_dp)
 {
+	/* The values must be in increasing order */
+	static const int cnl_rates[] = {
+		162000, 216000, 270000, 324000, 432000, 540000, 648000, 810000
+	};
+	static const int bxt_rates[] = {
+		162000, 216000, 243000, 270000, 324000, 432000, 540000
+	};
+	static const int skl_rates[] = {
+		162000, 216000, 270000, 324000, 432000, 540000
+	};
+	static const int hsw_rates[] = {
+		162000, 270000, 540000
+	};
+	static const int g4x_rates[] = {
+		162000, 270000
+	};
 	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);
 	const struct ddi_vbt_port_info *info =
@@ -288,11 +298,11 @@ intel_dp_set_source_rates(struct intel_dp *intel_dp)
 		size = ARRAY_SIZE(skl_rates);
 	} else if ((IS_HASWELL(dev_priv) && !IS_HSW_ULX(dev_priv)) ||
 		   IS_BROADWELL(dev_priv)) {
-		source_rates = default_rates;
-		size = ARRAY_SIZE(default_rates);
+		source_rates = hsw_rates;
+		size = ARRAY_SIZE(hsw_rates);
 	} else {
-		source_rates = default_rates;
-		size = ARRAY_SIZE(default_rates) - 1;
+		source_rates = g4x_rates;
+		size = ARRAY_SIZE(g4x_rates);
 	}
 
 	if (max_rate && vbt_max_rate)
@@ -354,7 +364,7 @@ static void intel_dp_set_common_rates(struct intel_dp *intel_dp)
 
 	/* Paranoia, there should always be something in common. */
 	if (WARN_ON(intel_dp->num_common_rates == 0)) {
-		intel_dp->common_rates[0] = default_rates[0];
+		intel_dp->common_rates[0] = 162000;
 		intel_dp->num_common_rates = 1;
 	}
 }