From 8d212a9ea65af7082adc577ec46b6d1372d0a8f3 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Mon, 19 Feb 2018 18:11:09 +0100 Subject: [PATCH] net: stmmac: set MSS for each tx DMA channel The DMA engine in dwmac4 can segment a large TSO packet to several smaller packets of (max) size Maximum Segment Size (MSS). The DMA engine fetches and saves the MSS via a context descriptor. This context decriptor has to be provided to each tx DMA channel. To ensure that this is done, move struct member mss from stmmac_priv to stmmac_tx_queue. stmmac_reset_queues_param() now also resets mss, together with other queue parameters, so reset of mss value can be removed from stmmac_resume(). init_dma_tx_desc_rings() now also resets mss, together with other queue parameters, so reset of mss value can be removed from stmmac_open(). This fixes tx queue timeouts for dwmac4, with DT property snps,tx-queues-to-use > 1, when running iperf3 with multiple threads. Fixes: ce736788e8a9 ("net: stmmac: adding multiple buffers for TX") Signed-off-by: Niklas Cassel Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/stmmac.h | 2 +- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 13 +++++-------- 2 files changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h index a916e13624eb..75161e1b7e55 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h @@ -58,6 +58,7 @@ struct stmmac_tx_queue { unsigned int dirty_tx; dma_addr_t dma_tx_phy; u32 tx_tail_addr; + u32 mss; }; struct stmmac_rx_queue { @@ -138,7 +139,6 @@ struct stmmac_priv { spinlock_t ptp_lock; void __iomem *mmcaddr; void __iomem *ptpaddr; - u32 mss; #ifdef CONFIG_DEBUG_FS struct dentry *dbgfs_dir; diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 7ad841434ec8..d38bf38f12f5 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1355,6 +1355,7 @@ static int init_dma_tx_desc_rings(struct net_device *dev) tx_q->dirty_tx = 0; tx_q->cur_tx = 0; + tx_q->mss = 0; netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, queue)); } @@ -1946,6 +1947,7 @@ static void stmmac_tx_err(struct stmmac_priv *priv, u32 chan) (i == DMA_TX_SIZE - 1)); tx_q->dirty_tx = 0; tx_q->cur_tx = 0; + tx_q->mss = 0; netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, chan)); stmmac_start_tx_dma(priv, chan); @@ -2632,7 +2634,6 @@ static int stmmac_open(struct net_device *dev) priv->dma_buf_sz = STMMAC_ALIGN(buf_sz); priv->rx_copybreak = STMMAC_RX_COPYBREAK; - priv->mss = 0; ret = alloc_dma_desc_resources(priv); if (ret < 0) { @@ -2872,10 +2873,10 @@ static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev) mss = skb_shinfo(skb)->gso_size; /* set new MSS value if needed */ - if (mss != priv->mss) { + if (mss != tx_q->mss) { mss_desc = tx_q->dma_tx + tx_q->cur_tx; priv->hw->desc->set_mss(mss_desc, mss); - priv->mss = mss; + tx_q->mss = mss; tx_q->cur_tx = STMMAC_GET_ENTRY(tx_q->cur_tx, DMA_TX_SIZE); } @@ -4436,6 +4437,7 @@ static void stmmac_reset_queues_param(struct stmmac_priv *priv) tx_q->cur_tx = 0; tx_q->dirty_tx = 0; + tx_q->mss = 0; } } @@ -4481,11 +4483,6 @@ int stmmac_resume(struct device *dev) stmmac_reset_queues_param(priv); - /* reset private mss value to force mss context settings at - * next tso xmit (only used for gmac4). - */ - priv->mss = 0; - stmmac_clear_descriptors(priv); stmmac_hw_setup(ndev, false); -- 2.20.1