alt_sgdma_construct_descriptor_burst(
(volatile struct alt_sgdma_descriptor *)&rx_desc[0],
(volatile struct alt_sgdma_descriptor *)&rx_desc[1],
(unsigned int)0x0, /* read addr */
alt_sgdma_construct_descriptor_burst(
(volatile struct alt_sgdma_descriptor *)&rx_desc[0],
(volatile struct alt_sgdma_descriptor *)&rx_desc[1],
(unsigned int)0x0, /* read addr */