From c79992fddee28bbd31b35ac297e1068d32930179 Mon Sep 17 00:00:00 2001 From: Simon Kagstrom Date: Wed, 25 Nov 2009 22:10:43 +0000 Subject: [PATCH] via-velocity: Re-enable transmit scatter-gather support The velocity hardware can handle up to 7 memory segments. This can be turned on and off via ethtool. The support was removed in commit 83c98a8cd04dd0f848574370594886ba3bf56750 but is re-enabled and cleaned up here. It's off by default. Signed-off-by: Simon Kagstrom Signed-off-by: David S. Miller --- drivers/net/via-velocity.c | 83 ++++++++++++++++++++++++-------------- 1 file changed, 53 insertions(+), 30 deletions(-) diff --git a/drivers/net/via-velocity.c b/drivers/net/via-velocity.c index 10c4fb25fb4b..a8009c217bd6 100644 --- a/drivers/net/via-velocity.c +++ b/drivers/net/via-velocity.c @@ -9,7 +9,6 @@ * * TODO * rx_copybreak/alignment - * Scatter gather * More testing * * The changes are (c) Copyright 2004, Red Hat Inc. @@ -1643,12 +1642,10 @@ out: */ static int velocity_init_td_ring(struct velocity_info *vptr) { - dma_addr_t curr; int j; /* Init the TD ring entries */ for (j = 0; j < vptr->tx.numq; j++) { - curr = vptr->tx.pool_dma[j]; vptr->tx.infos[j] = kcalloc(vptr->options.numtx, sizeof(struct velocity_td_info), @@ -1714,21 +1711,27 @@ err_free_dma_rings_0: * Release an transmit buffer. If the buffer was preallocated then * recycle it, if not then unmap the buffer. */ -static void velocity_free_tx_buf(struct velocity_info *vptr, struct velocity_td_info *tdinfo) +static void velocity_free_tx_buf(struct velocity_info *vptr, + struct velocity_td_info *tdinfo, struct tx_desc *td) { struct sk_buff *skb = tdinfo->skb; - int i; - int pktlen; /* * Don't unmap the pre-allocated tx_bufs */ if (tdinfo->skb_dma) { + int i; - pktlen = max_t(unsigned int, skb->len, ETH_ZLEN); for (i = 0; i < tdinfo->nskb_dma; i++) { - pci_unmap_single(vptr->pdev, tdinfo->skb_dma[i], pktlen, PCI_DMA_TODEVICE); - tdinfo->skb_dma[i] = 0; + size_t pktlen = max_t(size_t, skb->len, ETH_ZLEN); + + /* For scatter-gather */ + if (skb_shinfo(skb)->nr_frags > 0) + pktlen = max_t(size_t, pktlen, + td->td_buf[i].size & ~TD_QUEUE); + + pci_unmap_single(vptr->pdev, tdinfo->skb_dma[i], + le16_to_cpu(pktlen), PCI_DMA_TODEVICE); } } dev_kfree_skb_irq(skb); @@ -1930,7 +1933,7 @@ static int velocity_tx_srv(struct velocity_info *vptr, u32 status) stats->tx_packets++; stats->tx_bytes += tdinfo->skb->len; } - velocity_free_tx_buf(vptr, tdinfo); + velocity_free_tx_buf(vptr, tdinfo, td); vptr->tx.used[qnum]--; } vptr->tx.tail[qnum] = idx; @@ -2529,14 +2532,22 @@ static netdev_tx_t velocity_xmit(struct sk_buff *skb, struct velocity_td_info *tdinfo; unsigned long flags; int pktlen; - __le16 len; - int index; + int index, prev; + int i = 0; if (skb_padto(skb, ETH_ZLEN)) goto out; - pktlen = max_t(unsigned int, skb->len, ETH_ZLEN); - len = cpu_to_le16(pktlen); + /* The hardware can handle at most 7 memory segments, so merge + * the skb if there are more */ + if (skb_shinfo(skb)->nr_frags > 6 && __skb_linearize(skb)) { + kfree_skb(skb); + return NETDEV_TX_OK; + } + + pktlen = skb_shinfo(skb)->nr_frags == 0 ? + max_t(unsigned int, skb->len, ETH_ZLEN) : + skb_headlen(skb); spin_lock_irqsave(&vptr->lock, flags); @@ -2553,11 +2564,24 @@ static netdev_tx_t velocity_xmit(struct sk_buff *skb, */ tdinfo->skb = skb; tdinfo->skb_dma[0] = pci_map_single(vptr->pdev, skb->data, pktlen, PCI_DMA_TODEVICE); - td_ptr->tdesc0.len = len; + td_ptr->tdesc0.len = cpu_to_le16(pktlen); td_ptr->td_buf[0].pa_low = cpu_to_le32(tdinfo->skb_dma[0]); td_ptr->td_buf[0].pa_high = 0; - td_ptr->td_buf[0].size = len; - tdinfo->nskb_dma = 1; + td_ptr->td_buf[0].size = cpu_to_le16(pktlen); + + /* Handle fragments */ + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + + tdinfo->skb_dma[i + 1] = pci_map_page(vptr->pdev, frag->page, + frag->page_offset, frag->size, + PCI_DMA_TODEVICE); + + td_ptr->td_buf[i + 1].pa_low = cpu_to_le32(tdinfo->skb_dma[i + 1]); + td_ptr->td_buf[i + 1].pa_high = 0; + td_ptr->td_buf[i + 1].size = cpu_to_le16(frag->size); + } + tdinfo->nskb_dma = i + 1; td_ptr->tdesc1.cmd = TCPLS_NORMAL + (tdinfo->nskb_dma + 1) * 16; @@ -2578,23 +2602,21 @@ static netdev_tx_t velocity_xmit(struct sk_buff *skb, td_ptr->tdesc1.TCR |= (TCR0_UDPCK); td_ptr->tdesc1.TCR |= TCR0_IPCK; } - { - int prev = index - 1; + prev = index - 1; + if (prev < 0) + prev = vptr->options.numtx - 1; + td_ptr->tdesc0.len |= OWNED_BY_NIC; + vptr->tx.used[qnum]++; + vptr->tx.curr[qnum] = (index + 1) % vptr->options.numtx; - if (prev < 0) - prev = vptr->options.numtx - 1; - td_ptr->tdesc0.len |= OWNED_BY_NIC; - vptr->tx.used[qnum]++; - vptr->tx.curr[qnum] = (index + 1) % vptr->options.numtx; + if (AVAIL_TD(vptr, qnum) < 1) + netif_stop_queue(dev); - if (AVAIL_TD(vptr, qnum) < 1) - netif_stop_queue(dev); + td_ptr = &(vptr->tx.rings[qnum][prev]); + td_ptr->td_buf[0].size |= TD_QUEUE; + mac_tx_queue_wake(vptr->mac_regs, qnum); - td_ptr = &(vptr->tx.rings[qnum][prev]); - td_ptr->td_buf[0].size |= TD_QUEUE; - mac_tx_queue_wake(vptr->mac_regs, qnum); - } dev->trans_start = jiffies; spin_unlock_irqrestore(&vptr->lock, flags); out: @@ -3374,6 +3396,7 @@ static const struct ethtool_ops velocity_ethtool_ops = { .set_wol = velocity_ethtool_set_wol, .get_msglevel = velocity_get_msglevel, .set_msglevel = velocity_set_msglevel, + .set_sg = ethtool_op_set_sg, .get_link = velocity_get_link, .get_coalesce = velocity_get_coalesce, .set_coalesce = velocity_set_coalesce,