From 01dd70b52a43f033798e3ce53e576b0c882d5f26 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Thu, 6 Apr 2017 11:02:48 +1000 Subject: ftgmac100: Simplify rx pointer handling in the rx path We don't handle fragmented RX packets, so the "looping" helpers to locate the first segment of a packet or to drop a packet aren't actually helping. Take them out and simplify ftgmac100_rx_packet() further as a result. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: David S. Miller --- drivers/net/ethernet/faraday/ftgmac100.c | 92 +++++++++----------------------- 1 file changed, 24 insertions(+), 68 deletions(-) (limited to 'drivers/net/ethernet/faraday/ftgmac100.c') diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c index 82ab3676974c..44be11da9d64 100644 --- a/drivers/net/ethernet/faraday/ftgmac100.c +++ b/drivers/net/ethernet/faraday/ftgmac100.c @@ -431,34 +431,6 @@ static int ftgmac100_next_rx_pointer(int pointer) return (pointer + 1) & (RX_QUEUE_ENTRIES - 1); } -static void ftgmac100_rx_pointer_advance(struct ftgmac100 *priv) -{ - priv->rx_pointer = ftgmac100_next_rx_pointer(priv->rx_pointer); -} - -static struct ftgmac100_rxdes *ftgmac100_current_rxdes(struct ftgmac100 *priv) -{ - return &priv->descs->rxdes[priv->rx_pointer]; -} - -static struct ftgmac100_rxdes * -ftgmac100_rx_locate_first_segment(struct ftgmac100 *priv) -{ - struct ftgmac100_rxdes *rxdes = ftgmac100_current_rxdes(priv); - - while (ftgmac100_rxdes_packet_ready(rxdes)) { - if (ftgmac100_rxdes_first_segment(rxdes)) - return rxdes; - - ftgmac100_rxdes_set_dma_own(priv, rxdes); - ftgmac100_rx_pointer_advance(priv); - rxdes = ftgmac100_current_rxdes(priv); - } - - return NULL; -} - - static void ftgmac100_rx_packet_error(struct ftgmac100 *priv, struct ftgmac100_rxdes *rxdes) { @@ -476,51 +448,32 @@ static void ftgmac100_rx_packet_error(struct ftgmac100 *priv, netdev->stats.rx_length_errors++; } -static void ftgmac100_rx_drop_packet(struct ftgmac100 *priv) -{ - struct net_device *netdev = priv->netdev; - struct ftgmac100_rxdes *rxdes = ftgmac100_current_rxdes(priv); - bool done = false; - - if (net_ratelimit()) - netdev_dbg(netdev, "drop packet %p\n", rxdes); - - do { - if (ftgmac100_rxdes_last_segment(rxdes)) - done = true; - - ftgmac100_rxdes_set_dma_own(priv, rxdes); - ftgmac100_rx_pointer_advance(priv); - rxdes = ftgmac100_current_rxdes(priv); - } while (!done && ftgmac100_rxdes_packet_ready(rxdes)); - - netdev->stats.rx_dropped++; -} - static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed) { struct net_device *netdev = priv->netdev; struct ftgmac100_rxdes *rxdes; struct sk_buff *skb; struct page *page; - unsigned int size; + unsigned int pointer, size; dma_addr_t map; - rxdes = ftgmac100_rx_locate_first_segment(priv); - if (!rxdes) + /* Grab next RX descriptor */ + pointer = priv->rx_pointer; + rxdes = &priv->descs->rxdes[pointer]; + + /* Do we have a packet ? */ + if (!ftgmac100_rxdes_packet_ready(rxdes)) return false; - /* We don't support segmented rx frames, so drop these - * along with packets with errors. - */ - if (unlikely(!ftgmac100_rxdes_last_segment(rxdes))) { - ftgmac100_rx_drop_packet(priv); - return true; - } + /* We don't cope with fragmented RX packets */ + if (unlikely(!ftgmac100_rxdes_first_segment(rxdes) || + !ftgmac100_rxdes_last_segment(rxdes))) + goto drop; + + /* Any error (other than csum offload) flagged ? */ if (unlikely(ftgmac100_rxdes_any_error(rxdes))) { ftgmac100_rx_packet_error(priv, rxdes); - ftgmac100_rx_drop_packet(priv); - return true; + goto drop; } /* If the packet had no buffer (failed to allocate earlier) @@ -529,8 +482,7 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed) page = ftgmac100_rxdes_get_page(priv, rxdes); if (!page) { ftgmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC); - ftgmac100_rx_pointer_advance(priv); - return true; + goto drop; } /* start processing */ @@ -538,9 +490,7 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed) if (unlikely(!skb)) { if (net_ratelimit()) netdev_err(netdev, "rx skb alloc failed\n"); - - ftgmac100_rx_drop_packet(priv); - return true; + goto drop; } if (unlikely(ftgmac100_rxdes_multicast(rxdes))) @@ -577,8 +527,7 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed) ftgmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC); - ftgmac100_rx_pointer_advance(priv); - rxdes = ftgmac100_current_rxdes(priv); + priv->rx_pointer = ftgmac100_next_rx_pointer(pointer); /* Small frames are copied into linear part of skb to free one page */ if (skb->len <= 128) { @@ -601,6 +550,13 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed) (*processed)++; return true; + + drop: + /* Clean rxdes0 (which resets own bit) */ + rxdes->rxdes0 &= cpu_to_le32(priv->rxdes0_edorr_mask); + priv->rx_pointer = ftgmac100_next_rx_pointer(pointer); + netdev->stats.rx_dropped++; + return true; } static void ftgmac100_txdes_reset(const struct ftgmac100 *priv, -- cgit v1.2.3