From 580a690208321ed45addef5ef12e25b87f9f5dec Mon Sep 17 00:00:00 2001 From: Francois Romieu Date: Fri, 11 Jul 2008 00:03:44 +0200 Subject: [PATCH] via-velocity: remove the bounce buffers MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Executive summary: the bounce buffers are in my way - they use something like a 64 * 1500 bytes area of PCI consistent area - they are not resized when the MTU changes - they are used - to hand-pad undersized packets. skb_pad anyone ? - to linearize fragmented skbs whose fragment count goes beyond the 7 fragments hardware limit in order to claim scatter-gather support Actually the SG code is commented out and I wonder if it could not be implemented (ab-)using the large send feature of the chipset since the latter should support some multi-descriptor packet transmitting. Signed-off-by: Francois Romieu Fixed-by: Séguier Régis Signed-off-by: Jeff Garzik --- drivers/net/via-velocity.c | 72 ++++++++++---------------------------- drivers/net/via-velocity.h | 5 --- 2 files changed, 18 insertions(+), 59 deletions(-) diff --git a/drivers/net/via-velocity.c b/drivers/net/via-velocity.c index bcbf2fa9b94..fce2dfd0e9e 100644 --- a/drivers/net/via-velocity.c +++ b/drivers/net/via-velocity.c @@ -1104,7 +1104,6 @@ static int velocity_init_rings(struct velocity_info *vptr) { int i; unsigned int psize; - unsigned int tsize; dma_addr_t pool_dma; u8 *pool; @@ -1133,19 +1132,6 @@ static int velocity_init_rings(struct velocity_info *vptr) vptr->rd_pool_dma = pool_dma; - tsize = vptr->options.numtx * PKT_BUF_SZ * vptr->num_txq; - vptr->tx_bufs = pci_alloc_consistent(vptr->pdev, tsize, - &vptr->tx_bufs_dma); - - if (vptr->tx_bufs == NULL) { - printk(KERN_ERR "%s: DMA memory allocation failed.\n", - vptr->dev->name); - pci_free_consistent(vptr->pdev, psize, pool, pool_dma); - return -ENOMEM; - } - - memset(vptr->tx_bufs, 0, vptr->options.numtx * PKT_BUF_SZ * vptr->num_txq); - i = vptr->options.numrx * sizeof(struct rx_desc); pool += i; pool_dma += i; @@ -1169,16 +1155,10 @@ static int velocity_init_rings(struct velocity_info *vptr) static void velocity_free_rings(struct velocity_info *vptr) { - int size; - - size = vptr->options.numrx * sizeof(struct rx_desc) + - vptr->options.numtx * sizeof(struct tx_desc) * vptr->num_txq; + const int size = vptr->options.numrx * sizeof(struct rx_desc) + + vptr->options.numtx * sizeof(struct tx_desc) * vptr->num_txq; pci_free_consistent(vptr->pdev, size, vptr->rd_ring, vptr->rd_pool_dma); - - size = vptr->options.numtx * PKT_BUF_SZ * vptr->num_txq; - - pci_free_consistent(vptr->pdev, size, vptr->tx_bufs, vptr->tx_bufs_dma); } static inline void velocity_give_many_rx_descs(struct velocity_info *vptr) @@ -1313,10 +1293,8 @@ static void velocity_free_rd_ring(struct velocity_info *vptr) static int velocity_init_td_ring(struct velocity_info *vptr) { - int i, j; dma_addr_t curr; - struct tx_desc *td; - struct velocity_td_info *td_info; + unsigned int j; /* Init the TD ring entries */ for (j = 0; j < vptr->num_txq; j++) { @@ -1331,14 +1309,6 @@ static int velocity_init_td_ring(struct velocity_info *vptr) return -ENOMEM; } - for (i = 0; i < vptr->options.numtx; i++, curr += sizeof(struct tx_desc)) { - td = &(vptr->td_rings[j][i]); - td_info = &(vptr->td_infos[j][i]); - td_info->buf = vptr->tx_bufs + - (j * vptr->options.numtx + i) * PKT_BUF_SZ; - td_info->buf_dma = vptr->tx_bufs_dma + - (j * vptr->options.numtx + i) * PKT_BUF_SZ; - } vptr->td_tail[j] = vptr->td_curr[j] = vptr->td_used[j] = 0; } return 0; @@ -1867,7 +1837,7 @@ static void velocity_free_tx_buf(struct velocity_info *vptr, struct velocity_td_ /* * Don't unmap the pre-allocated tx_bufs */ - if (tdinfo->skb_dma && (tdinfo->skb_dma[0] != tdinfo->buf_dma)) { + if (tdinfo->skb_dma) { for (i = 0; i < tdinfo->nskb_dma; i++) { #ifdef VELOCITY_ZERO_COPY_SUPPORT @@ -2063,9 +2033,19 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) struct tx_desc *td_ptr; struct velocity_td_info *tdinfo; unsigned long flags; - int index; int pktlen = skb->len; - __le16 len = cpu_to_le16(pktlen); + __le16 len; + int index; + + + + if (skb->len < ETH_ZLEN) { + if (skb_padto(skb, ETH_ZLEN)) + goto out; + pktlen = ETH_ZLEN; + } + + len = cpu_to_le16(pktlen); #ifdef VELOCITY_ZERO_COPY_SUPPORT if (skb_shinfo(skb)->nr_frags > 6 && __skb_linearize(skb)) { @@ -2083,23 +2063,6 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) td_ptr->tdesc1.TCR = TCR0_TIC; td_ptr->td_buf[0].size &= ~TD_QUEUE; - /* - * Pad short frames. - */ - if (pktlen < ETH_ZLEN) { - /* Cannot occur until ZC support */ - pktlen = ETH_ZLEN; - len = cpu_to_le16(ETH_ZLEN); - skb_copy_from_linear_data(skb, tdinfo->buf, skb->len); - memset(tdinfo->buf + skb->len, 0, ETH_ZLEN - skb->len); - tdinfo->skb = skb; - tdinfo->skb_dma[0] = tdinfo->buf_dma; - td_ptr->tdesc0.len = len; - 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; /* queue is 0 anyway */ - tdinfo->nskb_dma = 1; - } else #ifdef VELOCITY_ZERO_COPY_SUPPORT if (skb_shinfo(skb)->nr_frags > 0) { int nfrags = skb_shinfo(skb)->nr_frags; @@ -2191,7 +2154,8 @@ static int velocity_xmit(struct sk_buff *skb, struct net_device *dev) } dev->trans_start = jiffies; spin_unlock_irqrestore(&vptr->lock, flags); - return 0; +out: + return NETDEV_TX_OK; } /** diff --git a/drivers/net/via-velocity.h b/drivers/net/via-velocity.h index 7387be4f428..86446147284 100644 --- a/drivers/net/via-velocity.h +++ b/drivers/net/via-velocity.h @@ -236,10 +236,8 @@ struct velocity_rd_info { struct velocity_td_info { struct sk_buff *skb; - u8 *buf; int nskb_dma; dma_addr_t skb_dma[7]; - dma_addr_t buf_dma; }; enum velocity_owner { @@ -1506,9 +1504,6 @@ struct velocity_info { dma_addr_t rd_pool_dma; dma_addr_t td_pool_dma[TX_QUEUE_NO]; - dma_addr_t tx_bufs_dma; - u8 *tx_bufs; - struct vlan_group *vlgrp; u8 ip_addr[4]; enum chip_type chip_id; -- 2.41.1