/** * gelic_card_decode_one_descr - processes an rx descriptor * @card: card structure * * returns 1 if a packet has been sent to the stack, otherwise 0 * * processes an rx descriptor by iommu-unmapping the data buffer and passing * the packet up to the stack */ static int gelic_card_decode_one_descr(struct gelic_card *card) { enum gelic_descr_dma_status status; struct gelic_descr_chain *chain = &card->rx_chain; struct gelic_descr *descr = chain->head; struct net_device *netdev = NULL; int dmac_chain_ended; status = gelic_descr_get_status(descr); /* is this descriptor terminated with next_descr == NULL? */ dmac_chain_ended = be32_to_cpu(descr->dmac_cmd_status) & GELIC_DESCR_RX_DMA_CHAIN_END; if (status == GELIC_DESCR_DMA_CARDOWNED) return 0; if (status == GELIC_DESCR_DMA_NOT_IN_USE) { dev_dbg(ctodev(card), "dormant descr? %p\n", descr); return 0; } /* netdevice select */ if (card->vlan_required) { unsigned int i; u16 vid; vid = *(u16 *)(descr->skb->data) & VLAN_VID_MASK; for (i = 0; i < GELIC_PORT_MAX; i++) { if (card->vlan[i].rx == vid) { netdev = card->netdev[i]; break; } }; if (GELIC_PORT_MAX <= i) { pr_info("%s: unknown packet vid=%x\n", __func__, vid); goto refill; } } else netdev = card->netdev[GELIC_PORT_ETHERNET]; if ((status == GELIC_DESCR_DMA_RESPONSE_ERROR) || (status == GELIC_DESCR_DMA_PROTECTION_ERROR) || (status == GELIC_DESCR_DMA_FORCE_END)) { dev_info(ctodev(card), "dropping RX descriptor with state %x\n", status); netdev->stats.rx_dropped++; goto refill; } if (status == GELIC_DESCR_DMA_BUFFER_FULL) { /* * Buffer full would occur if and only if * the frame length was longer than the size of this * descriptor's buffer. If the frame length was equal * to or shorter than buffer'size, FRAME_END condition * would occur. * Anyway this frame was longer than the MTU, * just drop it. */ dev_info(ctodev(card), "overlength frame\n"); goto refill; } /* * descriptoers any other than FRAME_END here should * be treated as error. */ if (status != GELIC_DESCR_DMA_FRAME_END) { dev_dbg(ctodev(card), "RX descriptor with state %x\n", status); goto refill; } /* ok, we've got a packet in descr */ gelic_net_pass_skb_up(descr, card, netdev); refill: /* * So that always DMAC can see the end * of the descriptor chain to avoid * from unwanted DMAC overrun. */ descr->next_descr_addr = 0; /* change the descriptor state: */ gelic_descr_set_status(descr, GELIC_DESCR_DMA_NOT_IN_USE); /* * this call can fail, but for now, just leave this * decriptor without skb */ gelic_descr_prepare_rx(card, descr); chain->tail = descr; chain->head = descr->next; /* * Set this descriptor the end of the chain. */ descr->prev->next_descr_addr = cpu_to_be32(descr->bus_addr); /* * If dmac chain was met, DMAC stopped. * thus re-enable it */ if (dmac_chain_ended) { card->rx_dma_restart_required = 1; dev_dbg(ctodev(card), "reenable rx dma scheduled\n"); } return 1; }
/** * gelic_net_decode_one_descr - processes an rx descriptor * @card: card structure * * returns 1 if a packet has been sent to the stack, otherwise 0 * * processes an rx descriptor by iommu-unmapping the data buffer and passing * the packet up to the stack */ static int gelic_net_decode_one_descr(struct gelic_net_card *card) { enum gelic_net_descr_status status; struct gelic_net_descr_chain *chain = &card->rx_chain; struct gelic_net_descr *descr = chain->tail; int dmac_chain_ended; status = gelic_net_get_descr_status(descr); /* is this descriptor terminated with next_descr == NULL? */ dmac_chain_ended = descr->dmac_cmd_status & GELIC_NET_DMAC_CMDSTAT_RXDCEIS; if (status == GELIC_NET_DESCR_CARDOWNED) return 0; if (status == GELIC_NET_DESCR_NOT_IN_USE) { dev_dbg(ctodev(card), "dormant descr? %p\n", descr); return 0; } if ((status == GELIC_NET_DESCR_RESPONSE_ERROR) || (status == GELIC_NET_DESCR_PROTECTION_ERROR) || (status == GELIC_NET_DESCR_FORCE_END)) { dev_info(ctodev(card), "dropping RX descriptor with state %x\n", status); card->netdev->stats.rx_dropped++; goto refill; } if (status == GELIC_NET_DESCR_BUFFER_FULL) { /* * Buffer full would occur if and only if * the frame length was longer than the size of this * descriptor's buffer. If the frame length was equal * to or shorter than buffer'size, FRAME_END condition * would occur. * Anyway this frame was longer than the MTU, * just drop it. */ dev_info(ctodev(card), "overlength frame\n"); goto refill; } /* * descriptoers any other than FRAME_END here should * be treated as error. */ if (status != GELIC_NET_DESCR_FRAME_END) { dev_dbg(ctodev(card), "RX descriptor with state %x\n", status); goto refill; } /* ok, we've got a packet in descr */ gelic_net_pass_skb_up(descr, card); refill: /* * So that always DMAC can see the end * of the descriptor chain to avoid * from unwanted DMAC overrun. */ descr->next_descr_addr = 0; /* change the descriptor state: */ gelic_net_set_descr_status(descr, GELIC_NET_DESCR_NOT_IN_USE); /* * this call can fail, but for now, just leave this * decriptor without skb */ gelic_net_prepare_rx_descr(card, descr); chain->head = descr; chain->tail = descr->next; /* * Set this descriptor the end of the chain. */ descr->prev->next_descr_addr = descr->bus_addr; /* * If dmac chain was met, DMAC stopped. * thus re-enable it */ if (dmac_chain_ended) { card->rx_dma_restart_required = 1; dev_dbg(ctodev(card), "reenable rx dma scheduled\n"); } return 1; }