diff --git a/libc/kernel/uapi/linux/fsi.h b/libc/kernel/uapi/linux/fsi.h
index fc88464..b080c21 100644
--- a/libc/kernel/uapi/linux/fsi.h
+++ b/libc/kernel/uapi/linux/fsi.h
@@ -48,4 +48,5 @@
 #define FSI_SCOM_READ _IOWR('s', 0x01, struct scom_access)
 #define FSI_SCOM_WRITE _IOWR('s', 0x02, struct scom_access)
 #define FSI_SCOM_RESET _IOW('s', 0x03, __u32)
+#define FSI_SBEFIFO_READ_TIMEOUT_SECONDS _IOW('s', 0x00, __u32)
 #endif