diff --git a/src/hal/support.h b/src/hal/support.h
index 3baeb0a..2cff960 100644
--- a/src/hal/support.h
+++ b/src/hal/support.h
@@ -44,30 +44,13 @@ extern hal_platform plat;
 extern int series;
 
 #if defined(__arm__)
-extern void *gm_video_thread(void);
 extern hal_chnstate gm_state[GM_VENC_CHN_NUM];
-
-extern void *v3_audio_thread(void);
-extern void *v3_video_thread(void);
 extern hal_chnstate v3_state[V4_VENC_CHN_NUM];
-
-extern void *v4_audio_thread(void);
-extern void *v4_video_thread(void);
 extern hal_chnstate v4_state[V4_VENC_CHN_NUM];
-
-extern void *i6_audio_thread(void);
-extern void *i6_video_thread(void);
 extern hal_chnstate i6_state[I6_VENC_CHN_NUM];
-
-extern void *i6c_audio_thread(void);
-extern void *i6c_video_thread(void);
 extern hal_chnstate i6c_state[I6C_VENC_CHN_NUM];
-
-extern void *i6f_audio_thread(void);
-extern void *i6f_video_thread(void);
 extern hal_chnstate i6f_state[I6F_VENC_CHN_NUM];
 #elif defined(__mips__)
-extern void *t31_video_thread(void);
 extern hal_chnstate t31_state[T31_VENC_CHN_NUM];
 #endif