diff --git a/va/va.h b/va/va.h
index 1d99fa6ff..db885bc2d 100644
--- a/va/va.h
+++ b/va/va.h
@@ -1053,6 +1053,14 @@ typedef enum {
      * columns supported for encoding with tile support.
      */
     VAConfigAttribEncMaxTileCols        = 57,
+    /**
+     * \brief VP9 encoding attribute. Read-only.
+     *
+     * This attribute exposes a number of capabilities of the underlying
+     * VP9 implementation. The attribute value is partitioned into fields as defined in the
+     * VAConfigAttribValEncVP9 union.
+     */
+    VAConfigAttribEncVP9                = 58,
     /**@}*/
     VAConfigAttribTypeMax
 } VAConfigAttribType;
@@ -1491,6 +1499,19 @@ typedef union _VAConfigAttribValEncPerBlockControl {
 /** \brief Driver supports decode processing rate report  */
 #define VA_PROCESSING_RATE_DECODE                     0x00000002
 /**@}*/
+
+/** @name segment ID map block size */
+/**@{*/
+/** \brief each segmentID represent a 16x16 block */
+#define VA_SEGID_BLOCK_16X16                          0
+/** \brief each segmentID represent a 32x32 block */
+#define VA_SEGID_BLOCK_32X32                          1
+/** \brief each segmentID represent a 64x64 block */
+#define VA_SEGID_BLOCK_64X64                          2
+/** \brief each segmentID represent a 8x8 block */
+#define VA_SEGID_BLOCK_8X8                            3
+/**@}*/
+
 /**
  * if an attribute is not applicable for a given
  * profile/entrypoint pair, then set the value to the following
diff --git a/va/va_enc_av1.h b/va/va_enc_av1.h
index d96c3f224..9d7f67f1e 100644
--- a/va/va_enc_av1.h
+++ b/va/va_enc_av1.h
@@ -148,8 +148,10 @@ typedef union _VAConfigAttribValEncAV1Ext1 {
          */
         uint32_t interpolation_filter          : 5;
         /**
-         * \brief Min segmentId block size accepted.
+         * \brief segmentId block size accepted.
          * Application need to send seg_id_block_size in PPS equal or larger than this value.
+         * one bit represent one block size defined as VA_SEGID_BLOCKXXXX
+         * should be (1 << VA_SEGID_BLOCKXXX | 1 << VA_SEGID_BLOCKXXX ... )
          */
         uint32_t min_segid_block_size_accepted : 8;
         /**
@@ -667,10 +669,7 @@ typedef struct  _VAEncPictureParameterBufferAV1 {
     } picture_flags;
 
     /** \brief Block size for each Segment ID in Segment Map.
-     *  0: 16x16 block size, default value;
-     *  1: 32x32 block size;
-     *  2: 64x64 block size;
-     *  3: 8x8 block size.
+     *  should be \c VA_SEGID_BLOCK_XXXX;
      */
     uint8_t     seg_id_block_size;
 
diff --git a/va/va_enc_vp9.h b/va/va_enc_vp9.h
index 107ab0c9c..40f32e3c3 100644
--- a/va/va_enc_vp9.h
+++ b/va/va_enc_vp9.h
@@ -507,8 +507,16 @@ typedef struct  _VAEncPictureParameterBufferVP9 {
      */
     uint32_t    skip_frames_size;
 
+    /** \brief Block size for each Segment ID in Segment Map.
+     *  This specify the granularity of media driver of reading and processing the segment map.
+     *  value should be VA_SEGID_BLOCK_XXX
+     */
+    uint8_t     seg_id_block_size;
+
+    uint8_t     va_reserved8[3];
+
     /** \brief Reserved bytes for future use, must be zero */
-    uint32_t    va_reserved[VA_PADDING_MEDIUM];
+    uint32_t    va_reserved[VA_PADDING_MEDIUM - 1];
 } VAEncPictureParameterBufferVP9;
 
 
@@ -587,13 +595,41 @@ typedef struct _VAEncMiscParameterTypeVP9PerSegmantParam {
  * \brief VP9 Block Segmentation ID Buffer
  *
  * The application provides a buffer of VAEncMacroblockMapBufferType containing
- * the initial segmentation id for each 8x8 block, one byte each, in raster scan order.
- * Rate control may reassign it.  For example, a 640x480 video, the buffer has 4800 entries.
+ * the initial segmentation id for each block, block size is specified by seg_id_block_size
+ * in VAEncPictureParameterBufferVP9  , one byte each, in raster scan order.
+ * Rate control may reassign it.  For example, a 640x480 video, seg_id_block_size is
+ * VA_SEGID_BLOCK_16X16 , the buffer has 1200 entries.
  * The value of each entry should be in the range [0..7], inclusive.
  * If segmentation is not enabled, the application does not need to provide it.
  */
 
 
+/** \brief Attribute value for VAConfigAttribEncVP9. */
+typedef union _VAConfigAttribValEncVP9 {
+    struct {
+        /**
+         * \brief segmentId block size accepted.
+         * This is the granularity of segmentation map.
+         * one bit represent one block size defined as VA_SEGID_BLOCKXXXX
+         * should be (1 << VA_SEGID_BLOCKXXX | 1 << VA_SEGID_BLOCKXXX ... )
+         */
+        uint32_t seg_id_block_size             : 8;
+
+        /**
+         * \brief Type of segment feature supported.
+         * (segment_feature_support & 0x01) == 1: SEG_LVL_ALT_Q is supported, 0: not.
+         * (segment_feature_support & 0x02) == 1: SEG_LVL_ALT_L is supported, 0: not.
+         * (segment_feature_support & 0x04) == 1: SEG_LVL_REF_FRAME is supported, 0: not.
+         * (segment_feature_support & 0x08) == 1: SEG_LVL_SKIP is supported, 0: not.
+         */
+        uint32_t segment_feature_support       : 4;
+
+        /** \brief Reserved bits for future, must be zero. */
+        uint32_t reserved                      : 20;
+    } bits;
+    uint32_t value;
+} VAConfigAttribValEncVP9;
+
 /**@}*/
 
 #ifdef __cplusplus
diff --git a/va/va_str.c b/va/va_str.c
index 9d651d0a0..7601cdef2 100644
--- a/va/va_str.c
+++ b/va/va_str.c
@@ -153,6 +153,7 @@ const char *vaConfigAttribTypeStr(VAConfigAttribType configAttribType)
         TOSTR(VAConfigAttribEncPerBlockControl);
         TOSTR(VAConfigAttribEncMaxTileRows);
         TOSTR(VAConfigAttribEncMaxTileCols);
+        TOSTR(VAConfigAttribEncVP9);
     case VAConfigAttribTypeMax:
         break;
     }