From fb8ef788680d48523321e5f150b23700a1caf980 Mon Sep 17 00:00:00 2001 From: Duan Fugang-B38611 Date: Thu, 20 Feb 2014 18:14:39 +0800 Subject: [PATCH] net: fec: fix potential issue to avoid fec interrupt lost and crc error The current flow: Set TX BD ready, and then set "INT" and "PINS" bit to enable tx interrupt generation and crc checksum. There has potential issue like as: CPU fec uDMA Set tx ready bit uDMA start the BD transmission Set "INT" bit Set "PINS" bit ... Above situation cause fec tx interrupt lost and fec MAC don't do CRC checksum. The patch fix the potential issue. Signed-off-by: Fugang Duan Acked-by: Frank Li Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec_main.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 903362a..479a7cb 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -389,12 +389,6 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *ndev) netdev_err(ndev, "Tx DMA memory map failed\n"); return NETDEV_TX_OK; } - /* Send it on its way. Tell FEC it's ready, interrupt when done, - * it's the last BD of the frame, and to put the CRC on the end. - */ - status |= (BD_ENET_TX_READY | BD_ENET_TX_INTR - | BD_ENET_TX_LAST | BD_ENET_TX_TC); - bdp->cbd_sc = status; if (fep->bufdesc_ex) { @@ -416,6 +410,13 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *ndev) } } + /* Send it on its way. Tell FEC it's ready, interrupt when done, + * it's the last BD of the frame, and to put the CRC on the end. + */ + status |= (BD_ENET_TX_READY | BD_ENET_TX_INTR + | BD_ENET_TX_LAST | BD_ENET_TX_TC); + bdp->cbd_sc = status; + bdp_pre = fec_enet_get_prevdesc(bdp, fep); if ((id_entry->driver_data & FEC_QUIRK_ERR006358) && !(bdp_pre->cbd_sc & BD_ENET_TX_READY)) { -- 2.7.4