[PATCH v1 04/16] drm/i915/bios: prepare for parsing VBT #57

["Michał Grzelak" <michal.grzelak@intel.com>]

Add dead, generic VBT #57 parsing code since searching for VBT #57 at
the moment is switched off by default.

Add a struct storing all VS/PE relevant data into intel_vbt_data.

Add other possible renames into the comment.

Allocate matrix of intel_ddi_buf_trans_entry. This "buffers' table" (or
"buffers' block", or "tables' block") will be used to store all deparsed
values from VBT #57. Store matrix's pointer in intel_vbt_data.

Deallocate whole matrix on driver removal.

Signed-off-by: Michał Grzelak <michal.grzelak@intel.com>
---
 drivers/gpu/drm/i915/display/intel_bios.c     | 44 +++++++++++++++++++
 .../gpu/drm/i915/display/intel_display_core.h |  9 ++++
 2 files changed, 53 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
index b6fe87c29aa7..778584c59fc6 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.c
+++ b/drivers/gpu/drm/i915/display/intel_bios.c
@@ -34,6 +34,7 @@
 #include <drm/drm_fixed.h>
 #include <drm/drm_print.h>
 
+#include "intel_ddi_buf_trans.h"
 #include "intel_display.h"
 #include "intel_display_core.h"
 #include "intel_display_rpm.h"
@@ -2183,6 +2184,38 @@ parse_compression_parameters(struct intel_display *display)
 	}
 }
 
+static void
+parse_vswing_preemph_override(struct intel_display *display)
+{
+	union intel_ddi_buf_trans_entry **bufs_table;
+	const struct bdb_vswing_preemph *block;
+	u8 num_rows;
+
+	if (display->vbt.version < 218)
+		return;
+
+	block = bdb_find_section(display, BDB_VSWING_PREEMPH);
+
+	/* pre-ICL GOP don't have VBT #57 */
+	if (!block)
+		return;
+
+	num_rows = DISPLAY_VER(display) >= 14 ? 16 : 10;
+
+	bufs_table = kzalloc(block->num_tables * sizeof(*bufs_table), GFP_KERNEL);
+
+	for (int idx = 0; idx < block->num_tables; idx++)
+		bufs_table[idx] = kzalloc(num_rows * sizeof(**bufs_table), GFP_KERNEL);
+
+	drm_dbg_kms(display->drm, "Vswing / Preemph Override not yet supported on the platform\n");
+	bufs_table = NULL;
+
+	display->vbt.vswing_preemph.bufs_table = bufs_table;
+	display->vbt.vswing_preemph.num_tables = block->num_tables;
+	display->vbt.vswing_preemph.num_rows = num_rows;
+	display->vbt.vswing_preemph.num_cols = block->num_columns;
+}
+
 static u8 translate_iboost(struct intel_display *display, u8 val)
 {
 	static const u8 mapping[] = { 1, 3, 7 }; /* See VBT spec */
@@ -2978,6 +3011,9 @@ init_vbt_defaults(struct intel_display *display)
 							      !HAS_PCH_SPLIT(display));
 	drm_dbg_kms(display->drm, "Set default to SSC at %d kHz\n",
 		    display->vbt.lvds_ssc_freq);
+
+	/* Vswing / Preemphasis Override */
+	display->vbt.vswing_preemph.bufs_table = NULL;
 }
 
 /* Common defaults which may be overridden by VBT. */
@@ -3274,6 +3310,7 @@ void intel_bios_init(struct intel_display *display)
 
 	/* Depends on child device list */
 	parse_compression_parameters(display);
+	parse_vswing_preemph_override(display);
 
 out:
 	if (!vbt) {
@@ -3358,6 +3395,13 @@ void intel_bios_driver_remove(struct intel_display *display)
 		list_del(&entry->node);
 		kfree(entry);
 	}
+
+	if (display->vbt.vswing_preemph.bufs_table) {
+		for (int idx = 0; idx < display->vbt.vswing_preemph.num_tables; idx++)
+			kfree(display->vbt.vswing_preemph.bufs_table[idx]);
+
+		kfree(display->vbt.vswing_preemph.bufs_table);
+	}
 }
 
 void intel_bios_fini_panel(struct intel_panel *panel)
diff --git a/drivers/gpu/drm/i915/display/intel_display_core.h b/drivers/gpu/drm/i915/display/intel_display_core.h
index d708d322aa85..c18465b1018b 100644
--- a/drivers/gpu/drm/i915/display/intel_display_core.h
+++ b/drivers/gpu/drm/i915/display/intel_display_core.h
@@ -233,6 +233,15 @@ struct intel_vbt_data {
 	struct list_head display_devices;
 	struct list_head bdb_blocks;
 
+	struct {
+		// union intel_ddi_buf_trans_entry **tables_block;
+		// union intel_ddi_buf_trans_entry **bufs_block;
+		union intel_ddi_buf_trans_entry **bufs_table;
+		int num_tables;
+		int num_cols;
+		int num_rows;
+	} vswing_preemph;
+
 	struct sdvo_device_mapping {
 		u8 initialized;
 		u8 dvo_port;
-- 
2.45.2