From e8ea290958aed32d8fea745fb199f259dc5dc00e Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 15 Apr 2010 23:31:17 +0000 Subject: [PATCH] ar71xx: fix up alignment handling - on ar724x, rx buffers can be aligned with an offset of 2, which keeps the ip header aligned - alignment offset is only added if the ar8216 workaround is not active and the phy driver does not advertise its own packet alignment - ar71xx and ar91xx can not handle rx alignment offsets, however taking a hit on unaligned exceptions seems to have less overhead than re-aligning the data for large packets - use memmove to re-align small packets, if necessary tested on ar9132, ar7240 and ar7242 based devices without ar8216 headers SVN-Revision: 20892 --- .../files/drivers/net/ag71xx/ag71xx_ar8216.c | 1 - .../files/drivers/net/ag71xx/ag71xx_main.c | 66 ++++++++++++------- 2 files changed, 41 insertions(+), 26 deletions(-) diff --git a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar8216.c b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar8216.c index 7801b9f0ed..7ec43b7221 100644 --- a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar8216.c +++ b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar8216.c @@ -39,7 +39,6 @@ int ag71xx_remove_ar8216_header(struct ag71xx *ag, struct sk_buff *skb, return -EINVAL; } - skb_put(skb, pktlen); skb_pull(skb, AR8216_HEADER_LEN); return 0; } diff --git a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c index 8d61294beb..a3b5f95989 100644 --- a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c +++ b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_main.c @@ -192,9 +192,28 @@ static void ag71xx_ring_rx_clean(struct ag71xx *ag) } } +static int ag71xx_rx_reserve(struct ag71xx *ag) +{ + int reserve = 0; + + if (ag71xx_get_pdata(ag)->is_ar724x) { + if (!ag71xx_has_ar8216(ag)) + reserve = 2; + + if (ag->phy_dev) + reserve += 4 - (ag->phy_dev->pkt_align % 4); + + reserve %= 4; + } + + return reserve + AG71XX_RX_PKT_RESERVE; +} + + static int ag71xx_ring_rx_init(struct ag71xx *ag) { struct ag71xx_ring *ring = &ag->rx_ring; + unsigned int reserve = ag71xx_rx_reserve(ag); unsigned int i; int ret; @@ -212,14 +231,14 @@ static int ag71xx_ring_rx_init(struct ag71xx *ag) struct sk_buff *skb; dma_addr_t dma_addr; - skb = dev_alloc_skb(AG71XX_RX_PKT_SIZE + AG71XX_RX_PKT_RESERVE); + skb = dev_alloc_skb(AG71XX_RX_PKT_SIZE + reserve); if (!skb) { ret = -ENOMEM; break; } skb->dev = ag->dev; - skb_reserve(skb, AG71XX_RX_PKT_RESERVE); + skb_reserve(skb, reserve); dma_addr = dma_map_single(&ag->dev->dev, skb->data, AG71XX_RX_PKT_SIZE, @@ -242,6 +261,7 @@ static int ag71xx_ring_rx_init(struct ag71xx *ag) static int ag71xx_ring_rx_refill(struct ag71xx *ag) { struct ag71xx_ring *ring = &ag->rx_ring; + unsigned int reserve = ag71xx_rx_reserve(ag); unsigned int count; count = 0; @@ -254,12 +274,11 @@ static int ag71xx_ring_rx_refill(struct ag71xx *ag) dma_addr_t dma_addr; struct sk_buff *skb; - skb = dev_alloc_skb(AG71XX_RX_PKT_SIZE + - AG71XX_RX_PKT_RESERVE); + skb = dev_alloc_skb(AG71XX_RX_PKT_SIZE + reserve); if (skb == NULL) break; - skb_reserve(skb, AG71XX_RX_PKT_RESERVE); + skb_reserve(skb, reserve); skb->dev = ag->dev; dma_addr = dma_map_single(&ag->dev->dev, skb->data, @@ -759,30 +778,26 @@ static int ag71xx_tx_packets(struct ag71xx *ag) return sent; } -static int ag71xx_rx_copy_skb(struct ag71xx *ag, struct sk_buff **pskb, - int pktlen) +static void ag71xx_rx_align_skb(struct ag71xx *ag, struct sk_buff *skb, int len) { - struct sk_buff *copy_skb; + int offset = ((unsigned long) skb->data) % 4; + void *data; - if (ag->phy_dev && (ag->phy_dev->pkt_align % 4) == 2) - goto keep; - - copy_skb = netdev_alloc_skb(ag->dev, pktlen + NET_IP_ALIGN); - if (!copy_skb) - return -ENOMEM; + if (offset == 2) + return; - skb_reserve(copy_skb, NET_IP_ALIGN); - skb_copy_from_linear_data(*pskb, copy_skb->data, pktlen); - skb_put(copy_skb, pktlen); + if (ag->phy_dev && ag->phy_dev->pkt_align != 0) + return; - dev_kfree_skb_any(*pskb); - *pskb = copy_skb; + if (len > 128) + return; - return 0; + if (WARN_ON(skb_headroom(skb) < 2)) + return; - keep: - skb_put(*pskb, pktlen); - return 0; + data = skb->data; + skb->data -= 2; + memmove(skb->data, data, len); } static int ag71xx_rx_packets(struct ag71xx *ag, int limit) @@ -822,10 +837,11 @@ static int ag71xx_rx_packets(struct ag71xx *ag, int limit) dev->stats.rx_packets++; dev->stats.rx_bytes += pktlen; + skb_put(skb, pktlen); if (ag71xx_has_ar8216(ag)) err = ag71xx_remove_ar8216_header(ag, skb, pktlen); - else - err = ag71xx_rx_copy_skb(ag, &skb, pktlen); + + ag71xx_rx_align_skb(ag, skb, pktlen); if (err) { dev->stats.rx_dropped++; -- 2.30.2