diff options
-rw-r--r-- | drivers/net/e100.c | 72 |
1 files changed, 63 insertions, 9 deletions
diff --git a/drivers/net/e100.c b/drivers/net/e100.c index 61696637a21..763810c7f33 100644 --- a/drivers/net/e100.c +++ b/drivers/net/e100.c @@ -285,6 +285,12 @@ enum scb_status { rus_mask = 0x3C, }; +enum ru_state { + RU_SUSPENDED = 0, + RU_RUNNING = 1, + RU_UNINITIALIZED = -1, +}; + enum scb_stat_ack { stat_ack_not_ours = 0x00, stat_ack_sw_gen = 0x04, @@ -526,6 +532,7 @@ struct nic { struct rx *rx_to_use; struct rx *rx_to_clean; struct rfd blank_rfd; + enum ru_state ru_running; spinlock_t cb_lock ____cacheline_aligned; spinlock_t cmd_lock; @@ -947,7 +954,7 @@ static void e100_get_defaults(struct nic *nic) ((nic->mac >= mac_82558_D101_A4) ? cb_cid : cb_i)); /* Template for a freshly allocated RFD */ - nic->blank_rfd.command = cpu_to_le16(cb_el & cb_s); + nic->blank_rfd.command = cpu_to_le16(cb_el); nic->blank_rfd.rbd = 0xFFFFFFFF; nic->blank_rfd.size = cpu_to_le16(VLAN_ETH_FRAME_LEN); @@ -1742,11 +1749,19 @@ static int e100_alloc_cbs(struct nic *nic) return 0; } -static inline void e100_start_receiver(struct nic *nic) +static inline void e100_start_receiver(struct nic *nic, struct rx *rx) { - /* Start if RFA is non-NULL */ - if(nic->rx_to_clean->skb) - e100_exec_cmd(nic, ruc_start, nic->rx_to_clean->dma_addr); + if(!nic->rxs) return; + if(RU_SUSPENDED != nic->ru_running) return; + + /* handle init time starts */ + if(!rx) rx = nic->rxs; + + /* (Re)start RU if suspended or idle and RFA is non-NULL */ + if(rx->skb) { + e100_exec_cmd(nic, ruc_start, rx->dma_addr); + nic->ru_running = RU_RUNNING; + } } #define RFD_BUF_LEN (sizeof(struct rfd) + VLAN_ETH_FRAME_LEN) @@ -1775,7 +1790,7 @@ static int e100_rx_alloc_skb(struct nic *nic, struct rx *rx) put_unaligned(cpu_to_le32(rx->dma_addr), (u32 *)&prev_rfd->link); wmb(); - prev_rfd->command &= ~cpu_to_le16(cb_el & cb_s); + prev_rfd->command &= ~cpu_to_le16(cb_el); pci_dma_sync_single_for_device(nic->pdev, rx->prev->dma_addr, sizeof(struct rfd), PCI_DMA_TODEVICE); } @@ -1813,6 +1828,10 @@ static int e100_rx_indicate(struct nic *nic, struct rx *rx, pci_unmap_single(nic->pdev, rx->dma_addr, RFD_BUF_LEN, PCI_DMA_FROMDEVICE); + /* this allows for a fast restart without re-enabling interrupts */ + if(le16_to_cpu(rfd->command) & cb_el) + nic->ru_running = RU_SUSPENDED; + /* Pull off the RFD and put the actual data (minus eth hdr) */ skb_reserve(skb, sizeof(struct rfd)); skb_put(skb, actual_size); @@ -1843,18 +1862,45 @@ static void e100_rx_clean(struct nic *nic, unsigned int *work_done, unsigned int work_to_do) { struct rx *rx; + int restart_required = 0; + struct rx *rx_to_start = NULL; + + /* are we already rnr? then pay attention!!! this ensures that + * the state machine progression never allows a start with a + * partially cleaned list, avoiding a race between hardware + * and rx_to_clean when in NAPI mode */ + if(RU_SUSPENDED == nic->ru_running) + restart_required = 1; /* Indicate newly arrived packets */ for(rx = nic->rx_to_clean; rx->skb; rx = nic->rx_to_clean = rx->next) { - if(e100_rx_indicate(nic, rx, work_done, work_to_do)) + int err = e100_rx_indicate(nic, rx, work_done, work_to_do); + if(-EAGAIN == err) { + /* hit quota so have more work to do, restart once + * cleanup is complete */ + restart_required = 0; + break; + } else if(-ENODATA == err) break; /* No more to clean */ } + /* save our starting point as the place we'll restart the receiver */ + if(restart_required) + rx_to_start = nic->rx_to_clean; + /* Alloc new skbs to refill list */ for(rx = nic->rx_to_use; !rx->skb; rx = nic->rx_to_use = rx->next) { if(unlikely(e100_rx_alloc_skb(nic, rx))) break; /* Better luck next time (see watchdog) */ } + + if(restart_required) { + // ack the rnr? + writeb(stat_ack_rnr, &nic->csr->scb.stat_ack); + e100_start_receiver(nic, rx_to_start); + if(work_done) + (*work_done)++; + } } static void e100_rx_clean_list(struct nic *nic) @@ -1862,6 +1908,8 @@ static void e100_rx_clean_list(struct nic *nic) struct rx *rx; unsigned int i, count = nic->params.rfds.count; + nic->ru_running = RU_UNINITIALIZED; + if(nic->rxs) { for(rx = nic->rxs, i = 0; i < count; rx++, i++) { if(rx->skb) { @@ -1883,6 +1931,7 @@ static int e100_rx_alloc_list(struct nic *nic) unsigned int i, count = nic->params.rfds.count; nic->rx_to_use = nic->rx_to_clean = NULL; + nic->ru_running = RU_UNINITIALIZED; if(!(nic->rxs = kcalloc(count, sizeof(struct rx), GFP_ATOMIC))) return -ENOMEM; @@ -1897,6 +1946,7 @@ static int e100_rx_alloc_list(struct nic *nic) } nic->rx_to_use = nic->rx_to_clean = nic->rxs; + nic->ru_running = RU_SUSPENDED; return 0; } @@ -1916,6 +1966,10 @@ static irqreturn_t e100_intr(int irq, void *dev_id) /* Ack interrupt(s) */ iowrite8(stat_ack, &nic->csr->scb.stat_ack); + /* We hit Receive No Resource (RNR); restart RU after cleaning */ + if(stat_ack & stat_ack_rnr) + nic->ru_running = RU_SUSPENDED; + if(likely(netif_rx_schedule_prep(netdev))) { e100_disable_irq(nic); __netif_rx_schedule(netdev); @@ -2007,7 +2061,7 @@ static int e100_up(struct nic *nic) if((err = e100_hw_init(nic))) goto err_clean_cbs; e100_set_multicast_list(nic->netdev); - e100_start_receiver(nic); + e100_start_receiver(nic, NULL); mod_timer(&nic->watchdog, jiffies); if((err = request_irq(nic->pdev->irq, e100_intr, IRQF_SHARED, nic->netdev->name, nic->netdev))) @@ -2088,7 +2142,7 @@ static int e100_loopback_test(struct nic *nic, enum loopback loopback_mode) mdio_write(nic->netdev, nic->mii.phy_id, MII_BMCR, BMCR_LOOPBACK); - e100_start_receiver(nic); + e100_start_receiver(nic, NULL); if(!(skb = netdev_alloc_skb(nic->netdev, ETH_DATA_LEN))) { err = -ENOMEM; |