RING_BD_ALIGN_ORDER
1 << RING_BD_ALIGN_ORDER, 0);
(!((addr) & ((0x1 << RING_BD_ALIGN_ORDER) - 1)))
(((offset) >> RING_BD_ALIGN_ORDER) & 0x1)
((u32)((((dma_addr_t)(pa)) >> RING_BD_ALIGN_ORDER) & 0x0fffffff))
((dma_addr_t)((val) & 0x0fffffff) << RING_BD_ALIGN_ORDER)