drm/i915/bios: Reorder panel DTD parsing

Reorder things so that we can parse the entier LFP data block
in one go. For now we just stick to parsing the DTD from it.

Also fix the misleading comment about block 42 being deprecated.
Only the DTD part is deprecated, the rest is still very much needed.

v2: Move the version check+comment into parse_generic_dtd() (Jani)
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220504150440.13748-2-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/display/intel_bios.c

@@ -488,25 +488,16 @@ parse_panel_options(struct drm_i915_private *i915)
 	}
 }
 
-/* Try to find integrated panel timing data */
 static void
-parse_lfp_panel_dtd(struct drm_i915_private *i915)
+parse_lfp_panel_dtd(struct drm_i915_private *i915,
+		    const struct bdb_lvds_lfp_data *lvds_lfp_data,
+		    const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs)
 {
-	const struct bdb_lvds_lfp_data *lvds_lfp_data;
-	const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;
 	const struct lvds_dvo_timing *panel_dvo_timing;
 	const struct lvds_fp_timing *fp_timing;
 	struct drm_display_mode *panel_fixed_mode;
 	int panel_type = i915->vbt.panel_type;
 
-	lvds_lfp_data = find_section(i915, BDB_LVDS_LFP_DATA);
-	if (!lvds_lfp_data)
-		return;
-
-	lvds_lfp_data_ptrs = find_section(i915, BDB_LVDS_LFP_DATA_PTRS);
-	if (!lvds_lfp_data_ptrs)
-		return;
-
 	panel_dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
 					       lvds_lfp_data_ptrs,
 					       panel_type);
@@ -537,6 +528,24 @@ parse_lfp_panel_dtd(struct drm_i915_private *i915)
 	}
 }
 
+static void
+parse_lfp_data(struct drm_i915_private *i915)
+{
+	const struct bdb_lvds_lfp_data *data;
+	const struct bdb_lvds_lfp_data_ptrs *ptrs;
+
+	ptrs = find_section(i915, BDB_LVDS_LFP_DATA_PTRS);
+	if (!ptrs)
+		return;
+
+	data = find_section(i915, BDB_LVDS_LFP_DATA);
+	if (!data)
+		return;
+
+	if (!i915->vbt.lfp_lvds_vbt_mode)
+		parse_lfp_panel_dtd(i915, data, ptrs);
+}
+
 static void
 parse_generic_dtd(struct drm_i915_private *i915)
 {
@@ -545,6 +554,17 @@ parse_generic_dtd(struct drm_i915_private *i915)
 	struct drm_display_mode *panel_fixed_mode;
 	int num_dtd;
 
+	/*
+	 * Older VBTs provided DTD information for internal displays through
+	 * the "LFP panel tables" block (42).  As of VBT revision 229 the
+	 * DTD information should be provided via a newer "generic DTD"
+	 * block (58).  Just to be safe, we'll try the new generic DTD block
+	 * first on VBT >= 229, but still fall back to trying the old LFP
+	 * block if that fails.
+	 */
+	if (i915->vbt.version < 229)
+		return;
+
 	generic_dtd = find_section(i915, BDB_GENERIC_DTD);
 	if (!generic_dtd)
 		return;
@@ -615,23 +635,6 @@ parse_generic_dtd(struct drm_i915_private *i915)
 	i915->vbt.lfp_lvds_vbt_mode = panel_fixed_mode;
 }
 
-static void
-parse_panel_dtd(struct drm_i915_private *i915)
-{
-	/*
-	 * Older VBTs provided provided DTD information for internal displays
-	 * through the "LFP panel DTD" block (42).  As of VBT revision 229,
-	 * that block is now deprecated and DTD information should be provided
-	 * via a newer "generic DTD" block (58).  Just to be safe, we'll
-	 * try the new generic DTD block first on VBT >= 229, but still fall
-	 * back to trying the old LFP block if that fails.
-	 */
-	if (i915->vbt.version >= 229)
-		parse_generic_dtd(i915);
-	if (!i915->vbt.lfp_lvds_vbt_mode)
-		parse_lfp_panel_dtd(i915);
-}
-
 static void
 parse_lfp_backlight(struct drm_i915_private *i915)
 {
@@ -2708,7 +2711,8 @@ void intel_bios_init(struct drm_i915_private *i915)
 	parse_general_features(i915);
 	parse_general_definitions(i915);
 	parse_panel_options(i915);
-	parse_panel_dtd(i915);
+	parse_generic_dtd(i915);
+	parse_lfp_data(i915);
 	parse_lfp_backlight(i915);
 	parse_sdvo_panel_data(i915);
 	parse_driver_features(i915);