sh_eth_txdesc
struct sh_eth_txdesc *txdesc;
ringsize = sizeof(struct sh_eth_txdesc) * mdp->num_tx_ring;
struct sh_eth_txdesc *txdesc = NULL;
tx_ringsize = sizeof(struct sh_eth_txdesc) * mdp->num_tx_ring;
struct sh_eth_txdesc *txdesc;
struct sh_eth_txdesc *tx_ring;