Hi all,
I think I found the reason for the Rx status FIFO overrun nic hang:
If the Rx fifo overflows, the nic sets RxStatusFIFOOver _instead_ of
IntrRxIntr.
Thus netdev_rx is never called, the rx ring is never refilled, nic
hangs.
The attached patch adds proper OOM handling to natsemi.c.
I've also copied the simpler netdev_close locking from ns83820.c.
-- Manfred --------------912444018D9767D36E609D9E Content-Type: text/plain; charset=us-ascii; name="patch-natsemi" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="patch-natsemi"--- 2.5/drivers/net/natsemi.c Fri Nov 23 20:35:23 2001 +++ build-2.5/drivers/net/natsemi.c Sat Jan 12 20:59:24 2002 @@ -101,6 +101,12 @@ version 1.0.13: * ETHTOOL_[GS]EEPROM support (Tim Hockin) + version 1.0.14: + * OOM error handling. + * reinit_ring() instead of {drain,init}_ring(). + * Rx status FIFO overrun bug fixed: + The nic sets that bit instead of IntrRxDone, + just call netdev_rx and hang is gone. TODO: * big endian support with CFG:BEM instead of cpu_to_le32 @@ -161,7 +167,7 @@ There are no ill effects from too-large receive rings. */ #define TX_RING_SIZE 16 #define TX_QUEUE_LEN 10 /* Limit ring entries actually used, min 4. */ -#define RX_RING_SIZE 64 +#define RX_RING_SIZE 32 /* Operational parameters that usually are not changed. */ /* Time in jiffies before concluding the transmitter is hung. */ @@ -612,6 +618,7 @@ unsigned int cur_rx, dirty_rx; /* Producer/consumer ring indices */ unsigned int cur_tx, dirty_tx; unsigned int rx_buf_sz; /* Based on MTU+slack. */ + unsigned int oom; /* These values are keep track of the transceiver/media in use. */ unsigned int full_duplex; /* Rx filter. */ @@ -640,9 +647,12 @@ static void netdev_timer(unsigned long data); static void tx_timeout(struct net_device *dev); static int alloc_ring(struct net_device *dev); +static void refill_rx(struct net_device *dev); static void init_ring(struct net_device *dev); +static void drain_tx(struct net_device *dev); static void drain_ring(struct net_device *dev); static void free_ring(struct net_device *dev); +static void reinit_ring(struct net_device *dev); static void init_registers(struct net_device *dev); static int start_tx(struct sk_buff *skb, struct net_device *dev); static void intr_handler(int irq, void *dev_instance, struct pt_regs *regs); @@ -1191,11 +1201,15 @@ } /* - * The frequency on this has been increased because of a nasty little problem. + * netdev_timer: + * Purpose: + * 1) check for link changes. Usually they are handled by the MII interrupt + * 2) check for sudden death of the NIC: * It seems that a reference set for this chip went out with incorrect info, * and there exist boards that aren't quite right. An unexpected voltage drop * can cause the PHY to get itself in a weird state (basically reset..). * NOTE: this only seems to affect revC chips. + * 3) check of death of the RX path due to OOM. */ static void netdev_timer(unsigned long data) { @@ -1213,17 +1227,22 @@ dev->name); } + spin_lock_irq(&np->lock); + /* check for a nasty random phy-reset - use dspcfg as a flag */ writew(1, ioaddr+PGSEL); dspcfg = readw(ioaddr+DSPCFG); writew(0, ioaddr+PGSEL); if (dspcfg != DSPCFG_VAL) { if (!netif_queue_stopped(dev)) { + spin_unlock_irq(&np->lock); printk(KERN_INFO "%s: possible phy reset: re-initializing\n", dev->name); disable_irq(dev->irq); spin_lock_irq(&np->lock); + natsemi_reset(dev); + reinit_ring(dev); init_registers(dev); spin_unlock_irq(&np->lock); enable_irq(dev->irq); @@ -1233,9 +1252,19 @@ } } else { /* init_registers() calls check_link() for the above case */ - spin_lock_irq(&np->lock); check_link(dev); - spin_unlock_irq(&np->lock); + } + spin_unlock_irq(&np->lock); + if (np->oom) { + disable_irq(dev->irq); + np->oom = 0; + refill_rx(dev); + enable_irq(dev->irq); + if (!np->oom) { + writel(RxOn, dev->base_addr + ChipCmd); + } else { + next_tick = 1; + } } mod_timer(&np->timer, jiffies + next_tick); } @@ -1277,8 +1306,7 @@ dump_ring(dev); natsemi_reset(dev); - drain_ring(dev); - init_ring(dev); + reinit_ring(dev); init_registers(dev); } else { printk(KERN_WARNING @@ -1305,15 +1333,53 @@ return 0; } +static void refill_rx(struct net_device *dev) +{ + struct netdev_private *np = dev->priv; + + /* Refill the Rx ring buffers. */ + for (; np->cur_rx - np->dirty_rx > 0; np->dirty_rx++) { + struct sk_buff *skb; + int entry = np->dirty_rx % RX_RING_SIZE; + if (np->rx_skbuff[entry] == NULL) { + skb = dev_alloc_skb(np->rx_buf_sz); + np->rx_skbuff[entry] = skb; + if (skb == NULL) + break; /* Better luck next round. */ + skb->dev = dev; /* Mark as being used by this device. */ + np->rx_dma[entry] = pci_map_single(np->pci_dev, + skb->data, skb->len, PCI_DMA_FROMDEVICE); + np->rx_ring[entry].addr = cpu_to_le32(np->rx_dma[entry]); + } + np->rx_ring[entry].cmd_status = + cpu_to_le32(np->rx_buf_sz); + } + if (np->cur_rx - np->dirty_tx == RX_RING_SIZE) { + if (debug > 2) + printk(KERN_INFO "%s: going OOM.\n", dev->name); + np->oom = 1; + } +} + /* Initialize the Rx and Tx rings, along with various 'dev' bits. */ static void init_ring(struct net_device *dev) { struct netdev_private *np = dev->priv; int i; - np->cur_rx = np->cur_tx = 0; - np->dirty_rx = np->dirty_tx = 0; + /* 1) TX ring */ + np->dirty_tx = np->cur_tx = 0; + for (i = 0; i < TX_RING_SIZE; i++) { + np->tx_skbuff[i] = NULL; + np->tx_ring[i].next_desc = cpu_to_le32(np->ring_dma + +sizeof(struct netdev_desc) + *((i+1)%TX_RING_SIZE+RX_RING_SIZE)); + np->tx_ring[i].cmd_status = 0; + } + /* 2) RX ring */ + np->dirty_rx = 0; + np->cur_rx = RX_RING_SIZE; np->rx_buf_sz = (dev->mtu <= 1500 ? PKT_BUF_SZ : dev->mtu + 32); np->rx_head_desc = &np->rx_ring[0]; @@ -1328,29 +1394,25 @@ np->rx_ring[i].cmd_status = cpu_to_le32(DescOwn); np->rx_skbuff[i] = NULL; } + refill_rx(dev); + dump_ring(dev); +} - /* Fill in the Rx buffers. Handle allocation failure gracefully. */ - for (i = 0; i < RX_RING_SIZE; i++) { - struct sk_buff *skb = dev_alloc_skb(np->rx_buf_sz); - np->rx_skbuff[i] = skb; - if (skb == NULL) - break; - skb->dev = dev; /* Mark as being used by this device. */ - np->rx_dma[i] = pci_map_single(np->pci_dev, - skb->data, skb->len, PCI_DMA_FROMDEVICE); - np->rx_ring[i].addr = cpu_to_le32(np->rx_dma[i]); - np->rx_ring[i].cmd_status = cpu_to_le32(np->rx_buf_sz); - } - np->dirty_rx = (unsigned int)(i - RX_RING_SIZE); +static void drain_tx(struct net_device *dev) +{ + struct netdev_private *np = dev->priv; + int i; for (i = 0; i < TX_RING_SIZE; i++) { + if (np->tx_skbuff[i]) { + pci_unmap_single(np->pci_dev, + np->rx_dma[i], + np->rx_skbuff[i]->len, + PCI_DMA_TODEVICE); + dev_kfree_skb(np->tx_skbuff[i]); + } np->tx_skbuff[i] = NULL; - np->tx_ring[i].next_desc = cpu_to_le32(np->ring_dma - +sizeof(struct netdev_desc) - *((i+1)%TX_RING_SIZE+RX_RING_SIZE)); - np->tx_ring[i].cmd_status = 0; } - dump_ring(dev); } static void drain_ring(struct net_device *dev) @@ -1371,16 +1433,29 @@ } np->rx_skbuff[i] = NULL; } - for (i = 0; i < TX_RING_SIZE; i++) { - if (np->tx_skbuff[i]) { - pci_unmap_single(np->pci_dev, - np->rx_dma[i], - np->rx_skbuff[i]->len, - PCI_DMA_TODEVICE); - dev_kfree_skb(np->tx_skbuff[i]); - } - np->tx_skbuff[i] = NULL; - } + drain_tx(dev); +} + +static void reinit_ring(struct net_device *dev) +{ + struct netdev_private *np = dev->priv; + int i; + + /* drain TX ring */ + drain_tx(dev); + np->dirty_tx = np->cur_tx = 0; + for (i=0;i<TX_RING_SIZE;i++) + np->tx_ring[i].cmd_status = 0; + + /* RX Ring */ + np->dirty_rx = 0; + np->cur_rx = RX_RING_SIZE; + np->rx_head_desc = &np->rx_ring[0]; + /* Initialize all Rx descriptors. */ + for (i = 0; i < RX_RING_SIZE; i++) + np->rx_ring[i].cmd_status = cpu_to_le32(DescOwn); + + refill_rx(dev); } static void free_ring(struct net_device *dev) @@ -1508,7 +1583,7 @@ if (intr_status == 0) break; - if (intr_status & (IntrRxDone | IntrRxIntr)) + if (intr_status & (IntrRxDone | IntrRxIntr | RxStatusFIFOOver)) netdev_rx(dev); if (intr_status & (IntrTxDone | IntrTxIntr | IntrTxIdle | IntrTxErr) ) { @@ -1610,26 +1685,14 @@ desc_status = le32_to_cpu(np->rx_head_desc->cmd_status); } - /* Refill the Rx ring buffers. */ - for (; np->cur_rx - np->dirty_rx > 0; np->dirty_rx++) { - struct sk_buff *skb; - entry = np->dirty_rx % RX_RING_SIZE; - if (np->rx_skbuff[entry] == NULL) { - skb = dev_alloc_skb(np->rx_buf_sz); - np->rx_skbuff[entry] = skb; - if (skb == NULL) - break; /* Better luck next round. */ - skb->dev = dev; /* Mark as being used by this device. */ - np->rx_dma[entry] = pci_map_single(np->pci_dev, - skb->data, skb->len, PCI_DMA_FROMDEVICE); - np->rx_ring[entry].addr = cpu_to_le32(np->rx_dma[entry]); - } - np->rx_ring[entry].cmd_status = - cpu_to_le32(np->rx_buf_sz); - } + refill_rx(dev); /* Restart Rx engine if stopped. */ - writel(RxOn, dev->base_addr + ChipCmd); + if (np->oom) + mod_timer(&np->timer, jiffies + 1); + else + writel(RxOn, dev->base_addr + ChipCmd); + } static void netdev_error(struct net_device *dev, int intr_status) @@ -2331,7 +2394,8 @@ /* enable the WOL interrupt. * Could be used to send a netlink message. */ - writel(readl(ioaddr + IntrMask) | WOLPkt, ioaddr + IntrMask); + writel(WOLPkt, ioaddr + IntrMask); + writel(1, ioaddr + IntrEnable); } } @@ -2341,7 +2405,6 @@ struct netdev_private *np = dev->priv; netif_stop_queue(dev); - netif_carrier_off(dev); if (debug > 1) { printk(KERN_DEBUG "%s: Shutting down ethercard, status was %4.4x.\n", @@ -2350,13 +2413,17 @@ dev->name, np->cur_tx, np->dirty_tx, np->cur_rx, np->dirty_rx); } + /* Disable interrupts, and flush posted writes */ + writel(0, ioaddr + IntrEnable); + readl(ioaddr + IntrEnable); + free_irq(dev->irq, dev); del_timer_sync(&np->timer); - - disable_irq(dev->irq); + /* Interrupt disabled, interrupt handler released, + * queue stopped, timer deleted. All async codepaths + * that access the driver are disabled. + */ spin_lock_irq(&np->lock); - /* Disable and clear interrupts */ - writel(0, ioaddr + IntrEnable); readl(ioaddr + IntrMask); readw(ioaddr + MIntrStatus); @@ -2369,17 +2436,6 @@ __get_stats(dev); spin_unlock_irq(&np->lock); - /* race: shared irq and as most nics the DP83815 - * reports _all_ interrupt conditions in IntrStatus, even - * disabled ones. - * packet received after disable_irq, but before stop_rxtx - * --> race. intr_handler would restart the rx process. - * netif_device_{de,a}tach around {enable,free}_irq. - */ - netif_device_detach(dev); - enable_irq(dev->irq); - free_irq(dev->irq, dev); - netif_device_attach(dev); /* clear the carrier last - an interrupt could reenable it otherwise */ netif_carrier_off(dev); @@ -2387,7 +2443,7 @@ drain_ring(dev); free_ring(dev); - { + { u32 wol = readl(ioaddr + WOLCmd) & WakeOptsSummary; if (wol) { /* restart the NIC in WOL mode.
--------------912444018D9767D36E609D9E--
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