From 716ca530e1c4515d8683c9d5be3d56b301758b66 Mon Sep 17 00:00:00 2001 From: James <> Date: Wed, 4 Nov 2015 11:49:21 +0000 Subject: trunk-47381 --- ...-set-received-skb-headroom-to-NET_SKB_PAD.patch | 66 ++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 target/linux/generic/patches-3.18/077-06-bgmac-set-received-skb-headroom-to-NET_SKB_PAD.patch (limited to 'target/linux/generic/patches-3.18/077-06-bgmac-set-received-skb-headroom-to-NET_SKB_PAD.patch') diff --git a/target/linux/generic/patches-3.18/077-06-bgmac-set-received-skb-headroom-to-NET_SKB_PAD.patch b/target/linux/generic/patches-3.18/077-06-bgmac-set-received-skb-headroom-to-NET_SKB_PAD.patch new file mode 100644 index 0000000..2c490ef --- /dev/null +++ b/target/linux/generic/patches-3.18/077-06-bgmac-set-received-skb-headroom-to-NET_SKB_PAD.patch @@ -0,0 +1,66 @@ +From: Felix Fietkau +Date: Sun, 12 Apr 2015 10:13:28 +0200 +Subject: [PATCH] bgmac: set received skb headroom to NET_SKB_PAD + +A packet buffer offset of 30 bytes is inefficient, because the first 2 +bytes end up in a different cacheline. + +Signed-off-by: Felix Fietkau +--- + +--- a/drivers/net/ethernet/broadcom/bgmac.c ++++ b/drivers/net/ethernet/broadcom/bgmac.c +@@ -346,13 +346,13 @@ static int bgmac_dma_rx_skb_for_slot(str + return -ENOMEM; + + /* Poison - if everything goes fine, hardware will overwrite it */ +- rx = buf; ++ rx = buf + BGMAC_RX_BUF_OFFSET; + rx->len = cpu_to_le16(0xdead); + rx->flags = cpu_to_le16(0xbeef); + + /* Map skb for the DMA */ +- dma_addr = dma_map_single(dma_dev, buf, BGMAC_RX_BUF_SIZE, +- DMA_FROM_DEVICE); ++ dma_addr = dma_map_single(dma_dev, buf + BGMAC_RX_BUF_OFFSET, ++ BGMAC_RX_BUF_SIZE, DMA_FROM_DEVICE); + if (dma_mapping_error(dma_dev, dma_addr)) { + bgmac_err(bgmac, "DMA mapping error\n"); + put_page(virt_to_head_page(buf)); +@@ -403,7 +403,7 @@ static int bgmac_dma_rx_read(struct bgma + while (ring->start != ring->end) { + struct device *dma_dev = bgmac->core->dma_dev; + struct bgmac_slot_info *slot = &ring->slots[ring->start]; +- struct bgmac_rx_header *rx = slot->buf; ++ struct bgmac_rx_header *rx = slot->buf + BGMAC_RX_BUF_OFFSET; + struct sk_buff *skb; + void *buf = slot->buf; + u16 len, flags; +@@ -454,8 +454,10 @@ static int bgmac_dma_rx_read(struct bgma + BGMAC_RX_BUF_SIZE, DMA_FROM_DEVICE); + + skb = build_skb(buf, BGMAC_RX_ALLOC_SIZE); +- skb_put(skb, BGMAC_RX_FRAME_OFFSET + len); +- skb_pull(skb, BGMAC_RX_FRAME_OFFSET); ++ skb_put(skb, BGMAC_RX_FRAME_OFFSET + ++ BGMAC_RX_BUF_OFFSET + len); ++ skb_pull(skb, BGMAC_RX_FRAME_OFFSET + ++ BGMAC_RX_BUF_OFFSET); + + skb_checksum_none_assert(skb); + skb->protocol = eth_type_trans(skb, bgmac->net_dev); +--- a/drivers/net/ethernet/broadcom/bgmac.h ++++ b/drivers/net/ethernet/broadcom/bgmac.h +@@ -360,9 +360,11 @@ + + #define BGMAC_RX_HEADER_LEN 28 /* Last 24 bytes are unused. Well... */ + #define BGMAC_RX_FRAME_OFFSET 30 /* There are 2 unused bytes between header and real data */ ++#define BGMAC_RX_BUF_OFFSET (NET_SKB_PAD + NET_IP_ALIGN - \ ++ BGMAC_RX_FRAME_OFFSET) + #define BGMAC_RX_MAX_FRAME_SIZE 1536 /* Copied from b44/tg3 */ + #define BGMAC_RX_BUF_SIZE (BGMAC_RX_FRAME_OFFSET + BGMAC_RX_MAX_FRAME_SIZE) +-#define BGMAC_RX_ALLOC_SIZE (SKB_DATA_ALIGN(BGMAC_RX_BUF_SIZE) + \ ++#define BGMAC_RX_ALLOC_SIZE (SKB_DATA_ALIGN(BGMAC_RX_BUF_SIZE + BGMAC_RX_BUF_OFFSET) + \ + SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) + + #define BGMAC_BFL_ENETROBO 0x0010 /* has ephy roboswitch spi */ -- cgit v1.2.3