diff options
-rw-r--r-- | drivers/net/ethernet/cadence/macb.h | 6 | ||||
-rw-r--r-- | drivers/net/ethernet/cadence/macb_main.c | 291 |
2 files changed, 191 insertions, 106 deletions
diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h index f0a7d8396a4a..7ca077b65eaa 100644 --- a/drivers/net/ethernet/cadence/macb.h +++ b/drivers/net/ethernet/cadence/macb.h @@ -1204,11 +1204,15 @@ struct macb_queue { unsigned int RBQP; unsigned int RBQPH; + /* Lock to protect tx_head and tx_tail */ + spinlock_t tx_ptr_lock; unsigned int tx_head, tx_tail; struct macb_dma_desc *tx_ring; struct macb_tx_skb *tx_skb; dma_addr_t tx_ring_dma; struct work_struct tx_error_task; + bool txubr_pending; + struct napi_struct napi_tx; dma_addr_t rx_ring_dma; dma_addr_t rx_buffers_dma; @@ -1217,7 +1221,7 @@ struct macb_queue { struct macb_dma_desc *rx_ring; struct sk_buff **rx_skbuff; void *rx_buffers; - struct napi_struct napi; + struct napi_struct napi_rx; struct queue_stats stats; #ifdef CONFIG_MACB_USE_HWSTAMP diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 6434e74c04f1..e993616308f8 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -959,7 +959,7 @@ static int macb_halt_tx(struct macb *bp) return -ETIMEDOUT; } -static void macb_tx_unmap(struct macb *bp, struct macb_tx_skb *tx_skb) +static void macb_tx_unmap(struct macb *bp, struct macb_tx_skb *tx_skb, int budget) { if (tx_skb->mapping) { if (tx_skb->mapped_as_page) @@ -972,7 +972,7 @@ static void macb_tx_unmap(struct macb *bp, struct macb_tx_skb *tx_skb) } if (tx_skb->skb) { - dev_kfree_skb_any(tx_skb->skb); + napi_consume_skb(tx_skb->skb, budget); tx_skb->skb = NULL; } } @@ -1025,12 +1025,13 @@ static void macb_tx_error_task(struct work_struct *work) (unsigned int)(queue - bp->queues), queue->tx_tail, queue->tx_head); - /* Prevent the queue IRQ handlers from running: each of them may call - * macb_tx_interrupt(), which in turn may call netif_wake_subqueue(). + /* Prevent the queue NAPI TX poll from running, as it calls + * macb_tx_complete(), which in turn may call netif_wake_subqueue(). * As explained below, we have to halt the transmission before updating * TBQP registers so we call netif_tx_stop_all_queues() to notify the * network engine about the macb/gem being halted. */ + napi_disable(&queue->napi_tx); spin_lock_irqsave(&bp->lock, flags); /* Make sure nobody is trying to queue up new packets */ @@ -1058,7 +1059,7 @@ static void macb_tx_error_task(struct work_struct *work) if (ctrl & MACB_BIT(TX_USED)) { /* skb is set for the last buffer of the frame */ while (!skb) { - macb_tx_unmap(bp, tx_skb); + macb_tx_unmap(bp, tx_skb, 0); tail++; tx_skb = macb_tx_skb(queue, tail); skb = tx_skb->skb; @@ -1088,7 +1089,7 @@ static void macb_tx_error_task(struct work_struct *work) desc->ctrl = ctrl | MACB_BIT(TX_USED); } - macb_tx_unmap(bp, tx_skb); + macb_tx_unmap(bp, tx_skb, 0); } /* Set end of TX queue */ @@ -1118,27 +1119,20 @@ static void macb_tx_error_task(struct work_struct *work) macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART)); spin_unlock_irqrestore(&bp->lock, flags); + napi_enable(&queue->napi_tx); } -static void macb_tx_interrupt(struct macb_queue *queue) +static int macb_tx_complete(struct macb_queue *queue, int budget) { - unsigned int tail; - unsigned int head; - u32 status; struct macb *bp = queue->bp; u16 queue_index = queue - bp->queues; + unsigned int tail; + unsigned int head; + int packets = 0; - status = macb_readl(bp, TSR); - macb_writel(bp, TSR, status); - - if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE) - queue_writel(queue, ISR, MACB_BIT(TCOMP)); - - netdev_vdbg(bp->dev, "macb_tx_interrupt status = 0x%03lx\n", - (unsigned long)status); - + spin_lock(&queue->tx_ptr_lock); head = queue->tx_head; - for (tail = queue->tx_tail; tail != head; tail++) { + for (tail = queue->tx_tail; tail != head && packets < budget; tail++) { struct macb_tx_skb *tx_skb; struct sk_buff *skb; struct macb_dma_desc *desc; @@ -1179,10 +1173,11 @@ static void macb_tx_interrupt(struct macb_queue *queue) queue->stats.tx_packets++; bp->dev->stats.tx_bytes += skb->len; queue->stats.tx_bytes += skb->len; + packets++; } /* Now we can safely release resources */ - macb_tx_unmap(bp, tx_skb); + macb_tx_unmap(bp, tx_skb, budget); /* skb is set only for the last buffer of the frame. * WARNING: at this point skb has been freed by @@ -1198,6 +1193,9 @@ static void macb_tx_interrupt(struct macb_queue *queue) CIRC_CNT(queue->tx_head, queue->tx_tail, bp->tx_ring_size) <= MACB_TX_WAKEUP_THRESH(bp)) netif_wake_subqueue(bp->dev, queue_index); + spin_unlock(&queue->tx_ptr_lock); + + return packets; } static void gem_rx_refill(struct macb_queue *queue) @@ -1554,54 +1552,51 @@ static int macb_rx(struct macb_queue *queue, struct napi_struct *napi, return received; } -static int macb_poll(struct napi_struct *napi, int budget) +static bool macb_rx_pending(struct macb_queue *queue) { - struct macb_queue *queue = container_of(napi, struct macb_queue, napi); struct macb *bp = queue->bp; - int work_done; - u32 status; + unsigned int entry; + struct macb_dma_desc *desc; + + entry = macb_rx_ring_wrap(bp, queue->rx_tail); + desc = macb_rx_desc(queue, entry); - status = macb_readl(bp, RSR); - macb_writel(bp, RSR, status); + /* Make hw descriptor updates visible to CPU */ + rmb(); - netdev_vdbg(bp->dev, "poll: status = %08lx, budget = %d\n", - (unsigned long)status, budget); + return (desc->addr & MACB_BIT(RX_USED)) != 0; +} + +static int macb_rx_poll(struct napi_struct *napi, int budget) +{ + struct macb_queue *queue = container_of(napi, struct macb_queue, napi_rx); + struct macb *bp = queue->bp; + int work_done; work_done = bp->macbgem_ops.mog_rx(queue, napi, budget); - if (work_done < budget) { - napi_complete_done(napi, work_done); - /* RSR bits only seem to propagate to raise interrupts when - * interrupts are enabled at the time, so if bits are already - * set due to packets received while interrupts were disabled, + netdev_vdbg(bp->dev, "RX poll: queue = %u, work_done = %d, budget = %d\n", + (unsigned int)(queue - bp->queues), work_done, budget); + + if (work_done < budget && napi_complete_done(napi, work_done)) { + queue_writel(queue, IER, bp->rx_intr_mask); + + /* Packet completions only seem to propagate to raise + * interrupts when interrupts are enabled at the time, so if + * packets were received while interrupts were disabled, * they will not cause another interrupt to be generated when * interrupts are re-enabled. - * Check for this case here. This has been seen to happen - * around 30% of the time under heavy network load. + * Check for this case here to avoid losing a wakeup. This can + * potentially race with the interrupt handler doing the same + * actions if an interrupt is raised just after enabling them, + * but this should be harmless. */ - status = macb_readl(bp, RSR); - if (status) { + if (macb_rx_pending(queue)) { + queue_writel(queue, IDR, bp->rx_intr_mask); if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE) queue_writel(queue, ISR, MACB_BIT(RCOMP)); - napi_reschedule(napi); - } else { - queue_writel(queue, IER, bp->rx_intr_mask); - - /* In rare cases, packets could have been received in - * the window between the check above and re-enabling - * interrupts. Therefore, a double-check is required - * to avoid losing a wakeup. This can potentially race - * with the interrupt handler doing the same actions - * if an interrupt is raised just after enabling them, - * but this should be harmless. - */ - status = macb_readl(bp, RSR); - if (unlikely(status)) { - queue_writel(queue, IDR, bp->rx_intr_mask); - if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE) - queue_writel(queue, ISR, MACB_BIT(RCOMP)); - napi_schedule(napi); - } + netdev_vdbg(bp->dev, "poll: packets pending, reschedule\n"); + napi_schedule(napi); } } @@ -1610,6 +1605,90 @@ static int macb_poll(struct napi_struct *napi, int budget) return work_done; } +static void macb_tx_restart(struct macb_queue *queue) +{ + struct macb *bp = queue->bp; + unsigned int head_idx, tbqp; + + spin_lock(&queue->tx_ptr_lock); + + if (queue->tx_head == queue->tx_tail) + goto out_tx_ptr_unlock; + + tbqp = queue_readl(queue, TBQP) / macb_dma_desc_get_size(bp); + tbqp = macb_adj_dma_desc_idx(bp, macb_tx_ring_wrap(bp, tbqp)); + head_idx = macb_adj_dma_desc_idx(bp, macb_tx_ring_wrap(bp, queue->tx_head)); + + if (tbqp == head_idx) + goto out_tx_ptr_unlock; + + spin_lock_irq(&bp->lock); + macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART)); + spin_unlock_irq(&bp->lock); + +out_tx_ptr_unlock: + spin_unlock(&queue->tx_ptr_lock); +} + +static bool macb_tx_complete_pending(struct macb_queue *queue) +{ + bool retval = false; + + spin_lock(&queue->tx_ptr_lock); + if (queue->tx_head != queue->tx_tail) { + /* Make hw descriptor updates visible to CPU */ + rmb(); + + if (macb_tx_desc(queue, queue->tx_tail)->ctrl & MACB_BIT(TX_USED)) + retval = true; + } + spin_unlock(&queue->tx_ptr_lock); + return retval; +} + +static int macb_tx_poll(struct napi_struct *napi, int budget) +{ + struct macb_queue *queue = container_of(napi, struct macb_queue, napi_tx); + struct macb *bp = queue->bp; + int work_done; + + work_done = macb_tx_complete(queue, budget); + + rmb(); // ensure txubr_pending is up to date + if (queue->txubr_pending) { + queue->txubr_pending = false; + netdev_vdbg(bp->dev, "poll: tx restart\n"); + macb_tx_restart(queue); + } + + netdev_vdbg(bp->dev, "TX poll: queue = %u, work_done = %d, budget = %d\n", + (unsigned int)(queue - bp->queues), work_done, budget); + + if (work_done < budget && napi_complete_done(napi, work_done)) { + queue_writel(queue, IER, MACB_BIT(TCOMP)); + + /* Packet completions only seem to propagate to raise + * interrupts when interrupts are enabled at the time, so if + * packets were sent while interrupts were disabled, + * they will not cause another interrupt to be generated when + * interrupts are re-enabled. + * Check for this case here to avoid losing a wakeup. This can + * potentially race with the interrupt handler doing the same + * actions if an interrupt is raised just after enabling them, + * but this should be harmless. + */ + if (macb_tx_complete_pending(queue)) { + queue_writel(queue, IDR, MACB_BIT(TCOMP)); + if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE) + queue_writel(queue, ISR, MACB_BIT(TCOMP)); + netdev_vdbg(bp->dev, "TX poll: packets pending, reschedule\n"); + napi_schedule(napi); + } + } + + return work_done; +} + static void macb_hresp_error_task(struct tasklet_struct *t) { struct macb *bp = from_tasklet(bp, t, hresp_err_tasklet); @@ -1649,29 +1728,6 @@ static void macb_hresp_error_task(struct tasklet_struct *t) netif_tx_start_all_queues(dev); } -static void macb_tx_restart(struct macb_queue *queue) -{ - unsigned int head = queue->tx_head; - unsigned int tail = queue->tx_tail; - struct macb *bp = queue->bp; - unsigned int head_idx, tbqp; - - if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE) - queue_writel(queue, ISR, MACB_BIT(TXUBR)); - - if (head == tail) - return; - - tbqp = queue_readl(queue, TBQP) / macb_dma_desc_get_size(bp); - tbqp = macb_adj_dma_desc_idx(bp, macb_tx_ring_wrap(bp, tbqp)); - head_idx = macb_adj_dma_desc_idx(bp, macb_tx_ring_wrap(bp, head)); - - if (tbqp == head_idx) - return; - - macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART)); -} - static irqreturn_t macb_wol_interrupt(int irq, void *dev_id) { struct macb_queue *queue = dev_id; @@ -1768,9 +1824,27 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id) if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE) queue_writel(queue, ISR, MACB_BIT(RCOMP)); - if (napi_schedule_prep(&queue->napi)) { + if (napi_schedule_prep(&queue->napi_rx)) { netdev_vdbg(bp->dev, "scheduling RX softirq\n"); - __napi_schedule(&queue->napi); + __napi_schedule(&queue->napi_rx); + } + } + + if (status & (MACB_BIT(TCOMP) | + MACB_BIT(TXUBR))) { + queue_writel(queue, IDR, MACB_BIT(TCOMP)); + if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE) + queue_writel(queue, ISR, MACB_BIT(TCOMP) | + MACB_BIT(TXUBR)); + + if (status & MACB_BIT(TXUBR)) { + queue->txubr_pending = true; + wmb(); // ensure softirq can see update + } + + if (napi_schedule_prep(&queue->napi_tx)) { + netdev_vdbg(bp->dev, "scheduling TX softirq\n"); + __napi_schedule(&queue->napi_tx); } } @@ -1784,12 +1858,6 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id) break; } - if (status & MACB_BIT(TCOMP)) - macb_tx_interrupt(queue); - - if (status & MACB_BIT(TXUBR)) - macb_tx_restart(queue); - /* Link change detection isn't possible with RMII, so we'll * add that if/when we get our hands on a full-blown MII PHY. */ @@ -2022,7 +2090,7 @@ dma_error: for (i = queue->tx_head; i != tx_head; i++) { tx_skb = macb_tx_skb(queue, i); - macb_tx_unmap(bp, tx_skb); + macb_tx_unmap(bp, tx_skb, 0); } return 0; @@ -2144,7 +2212,6 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev) u16 queue_index = skb_get_queue_mapping(skb); struct macb *bp = netdev_priv(dev); struct macb_queue *queue = &bp->queues[queue_index]; - unsigned long flags; unsigned int desc_cnt, nr_frags, frag_size, f; unsigned int hdrlen; bool is_lso; @@ -2201,16 +2268,16 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev) desc_cnt += DIV_ROUND_UP(frag_size, bp->max_tx_length); } - spin_lock_irqsave(&bp->lock, flags); + spin_lock_bh(&queue->tx_ptr_lock); /* This is a hard error, log it. */ if (CIRC_SPACE(queue->tx_head, queue->tx_tail, bp->tx_ring_size) < desc_cnt) { netif_stop_subqueue(dev, queue_index); - spin_unlock_irqrestore(&bp->lock, flags); netdev_dbg(bp->dev, "tx_head = %u, tx_tail = %u\n", queue->tx_head, queue->tx_tail); - return NETDEV_TX_BUSY; + ret = NETDEV_TX_BUSY; + goto unlock; } /* Map socket buffer for DMA transfer */ @@ -2223,13 +2290,15 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev) wmb(); skb_tx_timestamp(skb); + spin_lock_irq(&bp->lock); macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART)); + spin_unlock_irq(&bp->lock); if (CIRC_SPACE(queue->tx_head, queue->tx_tail, bp->tx_ring_size) < 1) netif_stop_subqueue(dev, queue_index); unlock: - spin_unlock_irqrestore(&bp->lock, flags); + spin_unlock_bh(&queue->tx_ptr_lock); return ret; } @@ -2763,8 +2832,10 @@ static int macb_open(struct net_device *dev) goto pm_exit; } - for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) - napi_enable(&queue->napi); + for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) { + napi_enable(&queue->napi_rx); + napi_enable(&queue->napi_tx); + } macb_init_hw(bp); @@ -2788,8 +2859,10 @@ phy_off: reset_hw: macb_reset_hw(bp); - for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) - napi_disable(&queue->napi); + for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) { + napi_disable(&queue->napi_rx); + napi_disable(&queue->napi_tx); + } macb_free_consistent(bp); pm_exit: pm_runtime_put_sync(&bp->pdev->dev); @@ -2805,8 +2878,10 @@ static int macb_close(struct net_device *dev) netif_tx_stop_all_queues(dev); - for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) - napi_disable(&queue->napi); + for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) { + napi_disable(&queue->napi_rx); + napi_disable(&queue->napi_tx); + } phylink_stop(bp->phylink); phylink_disconnect_phy(bp->phylink); @@ -3868,7 +3943,9 @@ static int macb_init(struct platform_device *pdev) queue = &bp->queues[q]; queue->bp = bp; - netif_napi_add(dev, &queue->napi, macb_poll, NAPI_POLL_WEIGHT); + spin_lock_init(&queue->tx_ptr_lock); + netif_napi_add(dev, &queue->napi_rx, macb_rx_poll, NAPI_POLL_WEIGHT); + netif_napi_add(dev, &queue->napi_tx, macb_tx_poll, NAPI_POLL_WEIGHT); if (hw_q) { queue->ISR = GEM_ISR(hw_q - 1); queue->IER = GEM_IER(hw_q - 1); @@ -4975,8 +5052,10 @@ static int __maybe_unused macb_suspend(struct device *dev) netif_device_detach(netdev); for (q = 0, queue = bp->queues; q < bp->num_queues; - ++q, ++queue) - napi_disable(&queue->napi); + ++q, ++queue) { + napi_disable(&queue->napi_rx); + napi_disable(&queue->napi_tx); + } if (!(bp->wol & MACB_WOL_ENABLED)) { rtnl_lock(); @@ -5054,8 +5133,10 @@ static int __maybe_unused macb_resume(struct device *dev) } for (q = 0, queue = bp->queues; q < bp->num_queues; - ++q, ++queue) - napi_enable(&queue->napi); + ++q, ++queue) { + napi_enable(&queue->napi_rx); + napi_enable(&queue->napi_tx); + } if (netdev->hw_features & NETIF_F_NTUPLE) gem_writel_n(bp, ETHT, SCRT2_ETHT, bp->pm_data.scrt2); |