From f917d58031fce6dfd7cea71259ea6a2b663ec813 Mon Sep 17 00:00:00 2001 From: Matteo Croce Date: Wed, 14 May 2008 00:58:32 +0200 Subject: [PATCH] cpmac bugfixes and enhancements * Resolve some locking issues using atomic_inc/atomic_dec * move status code in cpmac_check_status * unmark the BROKEN flag in Kconfig * move code which should have been in platform code in arch/mips/ar7/platform.c * fixed an IRQ storm which lets the kernel hang * fixed a double call to netif_start_queue which causes a kernel panic * don't fail to register the PHY, works on many devices now Signed-off-by: Matteo Croce Signed-off-by: Felix Fietkau Signed-off-by: Jeff Garzik --- drivers/net/cpmac.c | 234 +++++++++++++++++++++++++++++++++----------- 1 file changed, 179 insertions(+), 55 deletions(-) diff --git a/drivers/net/cpmac.c b/drivers/net/cpmac.c index 2b5740b3d1..7f3f62e1b1 100644 --- a/drivers/net/cpmac.c +++ b/drivers/net/cpmac.c @@ -38,6 +38,7 @@ #include #include #include +#include MODULE_AUTHOR("Eugene Konev "); MODULE_DESCRIPTION("TI AR7 ethernet driver (CPMAC)"); @@ -187,6 +188,7 @@ struct cpmac_desc { #define CPMAC_EOQ 0x1000 struct sk_buff *skb; struct cpmac_desc *next; + struct cpmac_desc *prev; dma_addr_t mapping; dma_addr_t data_mapping; }; @@ -208,6 +210,7 @@ struct cpmac_priv { struct work_struct reset_work; struct platform_device *pdev; struct napi_struct napi; + atomic_t reset_pending; }; static irqreturn_t cpmac_irq(int, void *); @@ -241,6 +244,16 @@ static void cpmac_dump_desc(struct net_device *dev, struct cpmac_desc *desc) printk("\n"); } +static void cpmac_dump_all_desc(struct net_device *dev) +{ + struct cpmac_priv *priv = netdev_priv(dev); + struct cpmac_desc *dump = priv->rx_head; + do { + cpmac_dump_desc(dev, dump); + dump = dump->next; + } while (dump != priv->rx_head); +} + static void cpmac_dump_skb(struct net_device *dev, struct sk_buff *skb) { int i; @@ -412,21 +425,42 @@ static struct sk_buff *cpmac_rx_one(struct cpmac_priv *priv, static int cpmac_poll(struct napi_struct *napi, int budget) { struct sk_buff *skb; - struct cpmac_desc *desc; - int received = 0; + struct cpmac_desc *desc, *restart; struct cpmac_priv *priv = container_of(napi, struct cpmac_priv, napi); + int received = 0, processed = 0; spin_lock(&priv->rx_lock); if (unlikely(!priv->rx_head)) { if (netif_msg_rx_err(priv) && net_ratelimit()) printk(KERN_WARNING "%s: rx: polling, but no queue\n", priv->dev->name); + spin_unlock(&priv->rx_lock); netif_rx_complete(priv->dev, napi); return 0; } desc = priv->rx_head; + restart = NULL; while (((desc->dataflags & CPMAC_OWN) == 0) && (received < budget)) { + processed++; + + if ((desc->dataflags & CPMAC_EOQ) != 0) { + /* The last update to eoq->hw_next didn't happen + * soon enough, and the receiver stopped here. + *Remember this descriptor so we can restart + * the receiver after freeing some space. + */ + if (unlikely(restart)) { + if (netif_msg_rx_err(priv)) + printk(KERN_ERR "%s: poll found a" + " duplicate EOQ: %p and %p\n", + priv->dev->name, restart, desc); + goto fatal_error; + } + + restart = desc->next; + } + skb = cpmac_rx_one(priv, desc); if (likely(skb)) { netif_receive_skb(skb); @@ -435,19 +469,90 @@ static int cpmac_poll(struct napi_struct *napi, int budget) desc = desc->next; } + if (desc != priv->rx_head) { + /* We freed some buffers, but not the whole ring, + * add what we did free to the rx list */ + desc->prev->hw_next = (u32)0; + priv->rx_head->prev->hw_next = priv->rx_head->mapping; + } + + /* Optimization: If we did not actually process an EOQ (perhaps because + * of quota limits), check to see if the tail of the queue has EOQ set. + * We should immediately restart in that case so that the receiver can + * restart and run in parallel with more packet processing. + * This lets us handle slightly larger bursts before running + * out of ring space (assuming dev->weight < ring_size) */ + + if (!restart && + (priv->rx_head->prev->dataflags & (CPMAC_OWN|CPMAC_EOQ)) + == CPMAC_EOQ && + (priv->rx_head->dataflags & CPMAC_OWN) != 0) { + /* reset EOQ so the poll loop (above) doesn't try to + * restart this when it eventually gets to this descriptor. + */ + priv->rx_head->prev->dataflags &= ~CPMAC_EOQ; + restart = priv->rx_head; + } + + if (restart) { + priv->dev->stats.rx_errors++; + priv->dev->stats.rx_fifo_errors++; + if (netif_msg_rx_err(priv) && net_ratelimit()) + printk(KERN_WARNING "%s: rx dma ring overrun\n", + priv->dev->name); + + if (unlikely((restart->dataflags & CPMAC_OWN) == 0)) { + if (netif_msg_drv(priv)) + printk(KERN_ERR "%s: cpmac_poll is trying to " + "restart rx from a descriptor that's " + "not free: %p\n", + priv->dev->name, restart); + goto fatal_error; + } + + cpmac_write(priv->regs, CPMAC_RX_PTR(0), restart->mapping); + } + priv->rx_head = desc; spin_unlock(&priv->rx_lock); if (unlikely(netif_msg_rx_status(priv))) printk(KERN_DEBUG "%s: poll processed %d packets\n", priv->dev->name, received); - if (desc->dataflags & CPMAC_OWN) { + if (processed == 0) { + /* we ran out of packets to read, + * revert to interrupt-driven mode */ netif_rx_complete(priv->dev, napi); - cpmac_write(priv->regs, CPMAC_RX_PTR(0), (u32)desc->mapping); cpmac_write(priv->regs, CPMAC_RX_INT_ENABLE, 1); return 0; } return 1; + +fatal_error: + /* Something went horribly wrong. + * Reset hardware to try to recover rather than wedging. */ + + if (netif_msg_drv(priv)) { + printk(KERN_ERR "%s: cpmac_poll is confused. " + "Resetting hardware\n", priv->dev->name); + cpmac_dump_all_desc(priv->dev); + printk(KERN_DEBUG "%s: RX_PTR(0)=0x%08x RX_ACK(0)=0x%08x\n", + priv->dev->name, + cpmac_read(priv->regs, CPMAC_RX_PTR(0)), + cpmac_read(priv->regs, CPMAC_RX_ACK(0))); + } + + spin_unlock(&priv->rx_lock); + netif_rx_complete(priv->dev, napi); + netif_stop_queue(priv->dev); + napi_disable(&priv->napi); + + atomic_inc(&priv->reset_pending); + cpmac_hw_stop(priv->dev); + if (!schedule_work(&priv->reset_work)) + atomic_dec(&priv->reset_pending); + return 0; + } static int cpmac_start_xmit(struct sk_buff *skb, struct net_device *dev) @@ -456,6 +561,9 @@ static int cpmac_start_xmit(struct sk_buff *skb, struct net_device *dev) struct cpmac_desc *desc; struct cpmac_priv *priv = netdev_priv(dev); + if (unlikely(atomic_read(&priv->reset_pending))) + return NETDEV_TX_BUSY; + if (unlikely(skb_padto(skb, ETH_ZLEN))) return NETDEV_TX_OK; @@ -621,8 +729,10 @@ static void cpmac_clear_rx(struct net_device *dev) desc->dataflags = CPMAC_OWN; dev->stats.rx_dropped++; } + desc->hw_next = desc->next->mapping; desc = desc->next; } + priv->rx_head->prev->hw_next = 0; } static void cpmac_clear_tx(struct net_device *dev) @@ -635,14 +745,14 @@ static void cpmac_clear_tx(struct net_device *dev) priv->desc_ring[i].dataflags = 0; if (priv->desc_ring[i].skb) { dev_kfree_skb_any(priv->desc_ring[i].skb); - if (netif_subqueue_stopped(dev, i)) - netif_wake_subqueue(dev, i); + priv->desc_ring[i].skb = NULL; } } } static void cpmac_hw_error(struct work_struct *work) { + int i; struct cpmac_priv *priv = container_of(work, struct cpmac_priv, reset_work); @@ -651,8 +761,48 @@ static void cpmac_hw_error(struct work_struct *work) spin_unlock(&priv->rx_lock); cpmac_clear_tx(priv->dev); cpmac_hw_start(priv->dev); - napi_enable(&priv->napi); - netif_start_queue(priv->dev); + barrier(); + atomic_dec(&priv->reset_pending); + + for (i = 0; i < CPMAC_QUEUES; i++) + netif_wake_subqueue(priv->dev, i); + netif_wake_queue(priv->dev); + cpmac_write(priv->regs, CPMAC_MAC_INT_ENABLE, 3); +} + +static void cpmac_check_status(struct net_device *dev) +{ + struct cpmac_priv *priv = netdev_priv(dev); + + u32 macstatus = cpmac_read(priv->regs, CPMAC_MAC_STATUS); + int rx_channel = (macstatus >> 8) & 7; + int rx_code = (macstatus >> 12) & 15; + int tx_channel = (macstatus >> 16) & 7; + int tx_code = (macstatus >> 20) & 15; + + if (rx_code || tx_code) { + if (netif_msg_drv(priv) && net_ratelimit()) { + /* Can't find any documentation on what these + *error codes actually are. So just log them and hope.. + */ + if (rx_code) + printk(KERN_WARNING "%s: host error %d on rx " + "channel %d (macstatus %08x), resetting\n", + dev->name, rx_code, rx_channel, macstatus); + if (tx_code) + printk(KERN_WARNING "%s: host error %d on tx " + "channel %d (macstatus %08x), resetting\n", + dev->name, tx_code, tx_channel, macstatus); + } + + netif_stop_queue(dev); + cpmac_hw_stop(dev); + if (schedule_work(&priv->reset_work)) + atomic_inc(&priv->reset_pending); + if (unlikely(netif_msg_hw(priv))) + cpmac_dump_regs(dev); + } + cpmac_write(priv->regs, CPMAC_MAC_INT_CLEAR, 0xff); } static irqreturn_t cpmac_irq(int irq, void *dev_id) @@ -683,49 +833,32 @@ static irqreturn_t cpmac_irq(int irq, void *dev_id) cpmac_write(priv->regs, CPMAC_MAC_EOI_VECTOR, 0); - if (unlikely(status & (MAC_INT_HOST | MAC_INT_STATUS))) { - if (netif_msg_drv(priv) && net_ratelimit()) - printk(KERN_ERR "%s: hw error, resetting...\n", - dev->name); - netif_stop_queue(dev); - napi_disable(&priv->napi); - cpmac_hw_stop(dev); - schedule_work(&priv->reset_work); - if (unlikely(netif_msg_hw(priv))) - cpmac_dump_regs(dev); - } + if (unlikely(status & (MAC_INT_HOST | MAC_INT_STATUS))) + cpmac_check_status(dev); return IRQ_HANDLED; } static void cpmac_tx_timeout(struct net_device *dev) { - struct cpmac_priv *priv = netdev_priv(dev); int i; + struct cpmac_priv *priv = netdev_priv(dev); spin_lock(&priv->lock); dev->stats.tx_errors++; spin_unlock(&priv->lock); if (netif_msg_tx_err(priv) && net_ratelimit()) printk(KERN_WARNING "%s: transmit timeout\n", dev->name); - /* - * FIXME: waking up random queue is not the best thing to - * do... on the other hand why we got here at all? - */ -#ifdef CONFIG_NETDEVICES_MULTIQUEUE + + atomic_inc(&priv->reset_pending); + barrier(); + cpmac_clear_tx(dev); + barrier(); + atomic_dec(&priv->reset_pending); + + netif_wake_queue(priv->dev); for (i = 0; i < CPMAC_QUEUES; i++) - if (priv->desc_ring[i].skb) { - priv->desc_ring[i].dataflags = 0; - dev_kfree_skb_any(priv->desc_ring[i].skb); - netif_wake_subqueue(dev, i); - break; - } -#else - priv->desc_ring[0].dataflags = 0; - if (priv->desc_ring[0].skb) - dev_kfree_skb_any(priv->desc_ring[0].skb); - netif_wake_queue(dev); -#endif + netif_wake_subqueue(dev, i); } static int cpmac_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) @@ -901,9 +1034,12 @@ static int cpmac_open(struct net_device *dev) desc->buflen = CPMAC_SKB_SIZE; desc->dataflags = CPMAC_OWN; desc->next = &priv->rx_head[(i + 1) % priv->ring_size]; + desc->next->prev = desc; desc->hw_next = (u32)desc->next->mapping; } + priv->rx_head->prev->hw_next = (u32)0; + if ((res = request_irq(dev->irq, cpmac_irq, IRQF_SHARED, dev->name, dev))) { if (netif_msg_drv(priv)) @@ -912,6 +1048,7 @@ static int cpmac_open(struct net_device *dev) goto fail_irq; } + atomic_set(&priv->reset_pending, 0); INIT_WORK(&priv->reset_work, cpmac_hw_error); cpmac_hw_start(dev); @@ -1007,21 +1144,10 @@ static int __devinit cpmac_probe(struct platform_device *pdev) if (phy_id == PHY_MAX_ADDR) { if (external_switch || dumb_switch) { - struct fixed_phy_status status = {}; - - /* - * FIXME: this should be in the platform code! - * Since there is not platform code at all (that is, - * no mainline users of that driver), place it here - * for now. - */ - phy_id = 0; - status.link = 1; - status.duplex = 1; - status.speed = 100; - fixed_phy_add(PHY_POLL, phy_id, &status); + mdio_bus_id = 0; /* fixed phys bus */ + phy_id = pdev->id; } else { - printk(KERN_ERR "cpmac: no PHY present\n"); + dev_err(&pdev->dev, "no PHY present\n"); return -ENODEV; } } @@ -1064,10 +1190,8 @@ static int __devinit cpmac_probe(struct platform_device *pdev) priv->msg_enable = netif_msg_init(debug_level, 0xff); memcpy(dev->dev_addr, pdata->dev_addr, sizeof(dev->dev_addr)); - snprintf(priv->phy_name, BUS_ID_SIZE, PHY_ID_FMT, mdio_bus_id, phy_id); - - priv->phy = phy_connect(dev, priv->phy_name, &cpmac_adjust_link, 0, - PHY_INTERFACE_MODE_MII); + priv->phy = phy_connect(dev, cpmac_mii.phy_map[phy_id]->dev.bus_id, + &cpmac_adjust_link, 0, PHY_INTERFACE_MODE_MII); if (IS_ERR(priv->phy)) { if (netif_msg_drv(priv)) printk(KERN_ERR "%s: Could not attach to PHY\n", -- 2.39.5