drm/i915: Parse VBT PSR block.

PSR (aka SRD) block is defined at VBT and currently being used.
Mainly/At-least to configure the amount of idle_frames require to get
back to PSR Entry.
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.h

@@ -1306,6 +1306,13 @@ enum drrs_support_type {
 	SEAMLESS_DRRS_SUPPORT = 2
 };
 
+enum psr_lines_to_wait {
+	PSR_0_LINES_TO_WAIT = 0,
+	PSR_1_LINE_TO_WAIT,
+	PSR_4_LINES_TO_WAIT,
+	PSR_8_LINES_TO_WAIT
+};
+
 struct intel_vbt_data {
 	struct drm_display_mode *lfp_lvds_vbt_mode; /* if any */
 	struct drm_display_mode *sdvo_lvds_vbt_mode; /* if any */
@@ -1334,6 +1341,15 @@ struct intel_vbt_data {
 	int edp_bpp;
 	struct edp_power_seq edp_pps;
 
+	struct {
+		bool full_link;
+		bool require_aux_wakeup;
+		int idle_frames;
+		enum psr_lines_to_wait lines_to_wait;
+		int tp1_wakeup_time;
+		int tp2_tp3_wakeup_time;
+	} psr;
+
 	struct {
 		u16 pwm_freq_hz;
 		bool present;

drivers/gpu/drm/i915/intel_bios.c

@@ -664,6 +664,50 @@ parse_edp(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
 	}
 }
 
+static void
+parse_psr(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
+{
+	struct bdb_psr *psr;
+	struct psr_table *psr_table;
+
+	psr = find_section(bdb, BDB_PSR);
+	if (!psr) {
+		DRM_DEBUG_KMS("No PSR BDB found.\n");
+		return;
+	}
+
+	psr_table = &psr->psr_table[panel_type];
+
+	dev_priv->vbt.psr.full_link = psr_table->full_link;
+	dev_priv->vbt.psr.require_aux_wakeup = psr_table->require_aux_to_wakeup;
+
+	/* Allowed VBT values goes from 0 to 15 */
+	dev_priv->vbt.psr.idle_frames = psr_table->idle_frames < 0 ? 0 :
+		psr_table->idle_frames > 15 ? 15 : psr_table->idle_frames;
+
+	switch (psr_table->lines_to_wait) {
+	case 0:
+		dev_priv->vbt.psr.lines_to_wait = PSR_0_LINES_TO_WAIT;
+		break;
+	case 1:
+		dev_priv->vbt.psr.lines_to_wait = PSR_1_LINE_TO_WAIT;
+		break;
+	case 2:
+		dev_priv->vbt.psr.lines_to_wait = PSR_4_LINES_TO_WAIT;
+		break;
+	case 3:
+		dev_priv->vbt.psr.lines_to_wait = PSR_8_LINES_TO_WAIT;
+		break;
+	default:
+		DRM_DEBUG_KMS("VBT has unknown PSR lines to wait %u\n",
+			      psr_table->lines_to_wait);
+		break;
+	}
+
+	dev_priv->vbt.psr.tp1_wakeup_time = psr_table->tp1_wakeup_time;
+	dev_priv->vbt.psr.tp2_tp3_wakeup_time = psr_table->tp2_tp3_wakeup_time;
+}
+
 static u8 *goto_next_sequence(u8 *data, int *size)
 {
 	u16 len;
@@ -1241,6 +1285,7 @@ intel_parse_bios(struct drm_device *dev)
 	parse_device_mapping(dev_priv, bdb);
 	parse_driver_features(dev_priv, bdb);
 	parse_edp(dev_priv, bdb);
+	parse_psr(dev_priv, bdb);
 	parse_mipi(dev_priv, bdb);
 	parse_ddi_ports(dev_priv, bdb);
 

drivers/gpu/drm/i915/intel_bios.h

@@ -80,7 +80,7 @@ struct vbios_data {
 #define BDB_EXT_MMIO_REGS	  6
 #define BDB_SWF_IO		  7
 #define BDB_SWF_MMIO		  8
-#define BDB_DOT_CLOCK_TABLE	  9
+#define BDB_PSR			  9
 #define BDB_MODE_REMOVAL_TABLE	 10
 #define BDB_CHILD_DEVICE_TABLE	 11
 #define BDB_DRIVER_FEATURES	 12
@@ -556,6 +556,26 @@ struct bdb_edp {
 	u16 edp_t3_optimization;
 } __packed;
 
+struct psr_table {
+	/* Feature bits */
+	u8 full_link:1;
+	u8 require_aux_to_wakeup:1;
+	u8 feature_bits_rsvd:6;
+
+	/* Wait times */
+	u8 idle_frames:4;
+	u8 lines_to_wait:3;
+	u8 wait_times_rsvd:1;
+
+	/* TP wake up time in multiple of 100 */
+	u16 tp1_wakeup_time;
+	u16 tp2_tp3_wakeup_time;
+} __packed;
+
+struct bdb_psr {
+	struct psr_table psr_table[16];
+} __packed;
+
 void intel_setup_bios(struct drm_device *dev);
 int intel_parse_bios(struct drm_device *dev);