rx_bd
#define TOTAL_RX_BD_PER_PAGE (BCM_PAGE_SIZE / sizeof(struct rx_bd))
#define TOTAL_PG_BD_PER_PAGE (BCM_PAGE_SIZE / sizeof(struct rx_bd))
struct rx_bd *rx_bd_chain[MAX_RX_PAGES];
struct rx_bd *pg_bd_chain[MAX_PG_PAGES];