CIX_MBOX_MSG_WORDS
u32 buf[CIX_MBOX_MSG_WORDS]; /* buf[0] must be the byte length of this array */
u32 data[CIX_MBOX_MSG_WORDS], len, i;
u32 data[CIX_MBOX_MSG_WORDS] = { 0 }, i = 0;
} while (!mbox_fifo_empty(chan) && i < CIX_MBOX_MSG_WORDS);
#define CIX_REG_DB_ACK CIX_REG_MSG(CIX_MBOX_MSG_WORDS) /* 0x80 */
#define CIX_FIFO_WM_DEFAULT CIX_MBOX_MSG_WORDS