diff options
Diffstat (limited to 'target/linux/generic/pending-5.15/732-01-net-ethernet-mtk_eth_soc-work-around-issue-with-send.patch')
| -rw-r--r-- | target/linux/generic/pending-5.15/732-01-net-ethernet-mtk_eth_soc-work-around-issue-with-send.patch | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/target/linux/generic/pending-5.15/732-01-net-ethernet-mtk_eth_soc-work-around-issue-with-send.patch b/target/linux/generic/pending-5.15/732-01-net-ethernet-mtk_eth_soc-work-around-issue-with-send.patch new file mode 100644 index 0000000000..777e6f0ed1 --- /dev/null +++ b/target/linux/generic/pending-5.15/732-01-net-ethernet-mtk_eth_soc-work-around-issue-with-send.patch @@ -0,0 +1,94 @@ +From: Felix Fietkau <nbd@nbd.name> +Date: Thu, 3 Nov 2022 12:38:49 +0100 +Subject: [PATCH] net: ethernet: mtk_eth_soc: work around issue with sending + small fragments + +When lots of frames are sent with a number of very small fragments, an +internal FIFO can overflow, causing the DMA engine to lock up lock up and +transmit attempts time out. + +Fix this on MT7986 by increasing the reserved FIFO space. +Fix this on older chips by detecting the presence of small fragments and use +skb_gso_segment + skb_linearize to deal with them. + +Signed-off-by: Felix Fietkau <nbd@nbd.name> +--- + +--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c ++++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c +@@ -1402,12 +1402,28 @@ static void mtk_wake_queue(struct mtk_et + } + } + ++static bool mtk_skb_has_small_frag(struct sk_buff *skb) ++{ ++ int min_size = 16; ++ int i; ++ ++ if (skb_headlen(skb) < min_size) ++ return true; ++ ++ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) ++ if (skb_frag_size(&skb_shinfo(skb)->frags[i]) < min_size) ++ return true; ++ ++ return false; ++} ++ + static netdev_tx_t mtk_start_xmit(struct sk_buff *skb, struct net_device *dev) + { + struct mtk_mac *mac = netdev_priv(dev); + struct mtk_eth *eth = mac->hw; + struct mtk_tx_ring *ring = ð->tx_ring; + struct net_device_stats *stats = &dev->stats; ++ struct sk_buff *segs, *next; + bool gso = false; + int tx_num; + +@@ -1429,6 +1445,18 @@ static netdev_tx_t mtk_start_xmit(struct + return NETDEV_TX_BUSY; + } + ++ if (!MTK_HAS_CAPS(eth->soc->caps, MTK_NETSYS_V2) && ++ skb_is_gso(skb) && mtk_skb_has_small_frag(skb)) { ++ segs = skb_gso_segment(skb, dev->features & ~NETIF_F_ALL_TSO); ++ if (IS_ERR(segs)) ++ goto drop; ++ ++ if (segs) { ++ consume_skb(skb); ++ skb = segs; ++ } ++ } ++ + /* TSO: fill MSS info in tcp checksum field */ + if (skb_is_gso(skb)) { + if (skb_cow_head(skb, 0)) { +@@ -1444,8 +1472,14 @@ static netdev_tx_t mtk_start_xmit(struct + } + } + +- if (mtk_tx_map(skb, dev, tx_num, ring, gso) < 0) +- goto drop; ++ skb_list_walk_safe(skb, skb, next) { ++ if ((!MTK_HAS_CAPS(eth->soc->caps, MTK_NETSYS_V2) && ++ mtk_skb_has_small_frag(skb) && skb_linearize(skb)) || ++ mtk_tx_map(skb, dev, tx_num, ring, gso) < 0) { ++ stats->tx_dropped++; ++ dev_kfree_skb_any(skb); ++ } ++ } + + if (unlikely(atomic_read(&ring->free_count) <= ring->thresh)) + netif_tx_stop_all_queues(dev); +--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h ++++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h +@@ -258,7 +258,7 @@ + #define MTK_CHK_DDONE_EN BIT(28) + #define MTK_DMAD_WR_WDONE BIT(26) + #define MTK_WCOMP_EN BIT(24) +-#define MTK_RESV_BUF (0x40 << 16) ++#define MTK_RESV_BUF (0x80 << 16) + #define MTK_MUTLI_CNT (0x4 << 12) + #define MTK_LEAKY_BUCKET_EN BIT(11) + |