va: Add encoding tuning mode

This provides a hint to driver about the requested encode tuning
in addition to quality level number. It can be used by hardware
encoders that supports low latency encoding as a special mode instead
of setting the lowest quality level.

Author: nowrep

va/va.h

@@ -1050,6 +1050,15 @@ typedef enum {
      * columns supported for encoding with tile support.
      */
     VAConfigAttribEncMaxTileCols        = 57,
+    /**
+     * \brief Encoding tuning mode attribute. Read-only.
+     *
+     * This attribute conveys whether the driver supports different tuning modes
+     * for encoding. The attribute value is any combination of VA_ENC_TUNING_MODE_XXX.
+     *
+     * The tuning mode is passed to the driver using VAEncMiscParameterBufferQualityLevel.
+     */
+    VAConfigAttribEncTuningMode         = 58,
     /**@}*/
     VAConfigAttribTypeMax
 } VAConfigAttribType;
@@ -2707,6 +2716,13 @@ typedef struct _VAEncMiscParameterBufferMultiPassFrameSize {
     unsigned long           va_reserved[VA_PADDING_LOW];
 } VAEncMiscParameterBufferMultiPassFrameSize;
 
+/** \brief Default tuning mode */
+#define VA_ENC_TUNING_MODE_DEFAULT                      0x00000000
+/** \brief Compromise quality to lower the latency of video encode operations */
+#define VA_ENC_TUNING_MODE_LOW_LATENCY                  0x00000001
+/** \brief Compromise quality for lowest latency of video encode operations */
+#define VA_ENC_TUNING_MODE_ULTRA_LOW_LATENCY            0x00000002
+
 /**
  * \brief Encoding quality level.
  *
@@ -2717,15 +2733,20 @@ typedef struct _VAEncMiscParameterBufferMultiPassFrameSize {
  * attribute. A lower value means higher quality, and a value of 1 represents the highest
  * quality. The quality level setting is used as a trade-off between quality and speed/power
  * consumption, with higher quality corresponds to lower speed and higher power consumption.
+ * The number of supported tuning modes can be queried through the VAConfigAttribEncTuningMode
+ * attribute.
  */
 typedef struct _VAEncMiscParameterBufferQualityLevel {
     /** \brief Encoding quality level setting. When set to 0, default quality
      * level is used.
      */
     uint32_t                quality_level;
 
+    /** \brief Encoding tuning mode setting, see VA_ENC_TUNING_MODE_XXX */
+    uint32_t                tuning_mode;
+
     /** \brief Reserved bytes for future use, must be zero */
-    uint32_t                va_reserved[VA_PADDING_LOW];
+    uint32_t                va_reserved[VA_PADDING_LOW - 1];
 } VAEncMiscParameterBufferQualityLevel;
 
 /**

va/va_str.c

@@ -151,6 +151,7 @@ const char *vaConfigAttribTypeStr(VAConfigAttribType configAttribType)
         TOSTR(VAConfigAttribEncPerBlockControl);
         TOSTR(VAConfigAttribEncMaxTileRows);
         TOSTR(VAConfigAttribEncMaxTileCols);
+        TOSTR(VAConfigAttribEncTuningMode);
     case VAConfigAttribTypeMax:
         break;
     }

va/va_trace.c

@@ -3642,6 +3642,7 @@ static void va_TraceVAEncMiscParameterBuffer(
 
         va_TraceMsg(trace_ctx, "\t--VAEncMiscParameterBufferQualityLevel\n");
         va_TraceMsg(trace_ctx, "\tquality_level = %d\n", p->quality_level);
+        va_TraceMsg(trace_ctx, "\ttuning_mode = %d\n", p->tuning_mode);
         break;
     }
     case VAEncMiscParameterTypeROI: {