diff options
| author | Claudiu Manoil <claudiu.manoil@freescale.com> | 2013-08-05 17:20:09 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-08-05 12:29:15 -0700 |
| commit | 02d88fb4fb6a580b0224b3bf07bbfd9d4806f6fb (patch) | |
| tree | 671f9df5f8e59adcc3f6f2944e0b9f63501b885e /drivers/net/ethernet/freescale/gianfar.c | |
| parent | 7864a1adf7291993d74923fdd0a45459ce9da27e (diff) | |
gianfar: Fix Tx csum generation errata handling
Both [eTSEC76] and [eTSEC12] errata relate to Tx checksum generation
(for some MPC83xx and MCP8548 older revisions). They require the same
workaround: manual checksum computation and insertion, and disabling
the H/W Tx csum acceleration feature (per frame) through Tx FCB
(Frame Control Block) csum offload settings.
The workaround for [eTSEC76] needs to be fixed because it currently
fails to disable H/W Tx csum insertion via FCB. This patch fixes it
and provides a common workaround implementation for both Tx csum errata.
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/freescale/gianfar.c')
| -rw-r--r-- | drivers/net/ethernet/freescale/gianfar.c | 44 |
1 files changed, 25 insertions, 19 deletions
diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c index dbb34f7ce448..352035e440d8 100644 --- a/drivers/net/ethernet/freescale/gianfar.c +++ b/drivers/net/ethernet/freescale/gianfar.c @@ -2051,6 +2051,24 @@ static inline struct txbd8 *next_txbd(struct txbd8 *bdp, struct txbd8 *base, return skip_txbd(bdp, 1, base, ring_size); } +/* eTSEC12: csum generation not supported for some fcb offsets */ +static inline bool gfar_csum_errata_12(struct gfar_private *priv, + unsigned long fcb_addr) +{ + return (gfar_has_errata(priv, GFAR_ERRATA_12) && + (fcb_addr % 0x20) > 0x18); +} + +/* eTSEC76: csum generation for frames larger than 2500 may + * cause excess delays before start of transmission + */ +static inline bool gfar_csum_errata_76(struct gfar_private *priv, + unsigned int len) +{ + return (gfar_has_errata(priv, GFAR_ERRATA_76) && + (len > 2500)); +} + /* This is called by the kernel when a frame is ready for transmission. * It is pointed to by the dev->hard_start_xmit function pointer */ @@ -2068,19 +2086,6 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) unsigned long flags; unsigned int nr_frags, nr_txbds, length, fcb_length = GMAC_FCB_LEN; - /* TOE=1 frames larger than 2500 bytes may see excess delays - * before start of transmission. - */ - if (unlikely(gfar_has_errata(priv, GFAR_ERRATA_76) && - skb->ip_summed == CHECKSUM_PARTIAL && - skb->len > 2500)) { - int ret; - - ret = skb_checksum_help(skb); - if (ret) - return ret; - } - rq = skb->queue_mapping; tx_queue = priv->tx_queue[rq]; txq = netdev_get_tx_queue(dev, rq); @@ -2187,14 +2192,15 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev) /* Set up checksumming */ if (CHECKSUM_PARTIAL == skb->ip_summed) { fcb = gfar_add_fcb(skb); - /* as specified by errata */ - if (unlikely(gfar_has_errata(priv, GFAR_ERRATA_12) && - ((unsigned long)fcb % 0x20) > 0x18)) { + lstatus |= BD_LFLAG(TXBD_TOE); + gfar_tx_checksum(skb, fcb, fcb_length); + + if (unlikely(gfar_csum_errata_12(priv, (unsigned long)fcb)) || + unlikely(gfar_csum_errata_76(priv, skb->len))) { __skb_pull(skb, GMAC_FCB_LEN); skb_checksum_help(skb); - } else { - lstatus |= BD_LFLAG(TXBD_TOE); - gfar_tx_checksum(skb, fcb, fcb_length); + lstatus &= ~(BD_LFLAG(TXBD_TOE)); + fcb = NULL; } } |