From 3b12e0141f7a97c3b84731b5f935ed738bb6f960 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Wed, 26 Sep 2007 17:58:47 -0700 Subject: sky2: sky2 FE+ receive status workaround The Yukon FE+ chip appears to have a hardware glitch that causes bogus receive status values to be posted. The data in the packet is good, but the status value is random garbage. As a temporary workaround until the problem is better understood, implement the workaround the vendor driver used of ignoring the status value on this chip. Since this means trusting dodgy hardware values; add additional checking of the receive packet length. Signed-off-by: Stephen Hemminger Signed-off-by: Jeff Garzik --- drivers/net/sky2.c | 28 +++++++++++++++++----------- 1 file changed, 17 insertions(+), 11 deletions(-) (limited to 'drivers') diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c index 0792031a5cf9..a3de0b6127eb 100644 --- a/drivers/net/sky2.c +++ b/drivers/net/sky2.c @@ -2148,6 +2148,18 @@ static struct sk_buff *sky2_receive(struct net_device *dev, sky2->rx_next = (sky2->rx_next + 1) % sky2->rx_pending; prefetch(sky2->rx_ring + sky2->rx_next); + if (length < ETH_ZLEN || length > sky2->rx_data_size) + goto len_error; + + /* This chip has hardware problems that generates bogus status. + * So do only marginal checking and expect higher level protocols + * to handle crap frames. + */ + if (sky2->hw->chip_id == CHIP_ID_YUKON_FE_P && + sky2->hw->chip_rev == CHIP_REV_YU_FE2_A0 && + length != count) + goto okay; + if (status & GMR_FS_ANY_ERR) goto error; @@ -2156,8 +2168,9 @@ static struct sk_buff *sky2_receive(struct net_device *dev, /* if length reported by DMA does not match PHY, packet was truncated */ if (length != count) - goto len_mismatch; + goto len_error; +okay: if (length < copybreak) skb = receive_copy(sky2, re, length); else @@ -2167,13 +2180,13 @@ resubmit: return skb; -len_mismatch: +len_error: /* Truncation of overlength packets causes PHY length to not match MAC length */ ++sky2->net_stats.rx_length_errors; if (netif_msg_rx_err(sky2) && net_ratelimit()) - pr_info(PFX "%s: rx length mismatch: length %d status %#x\n", - dev->name, length, status); + pr_info(PFX "%s: rx length error: status %#x length %d\n", + dev->name, status, length); goto resubmit; error: @@ -3934,13 +3947,6 @@ static __devinit struct net_device *sky2_init_netdev(struct sky2_hw *hw, sky2->hw = hw; sky2->msg_enable = netif_msg_init(debug, default_msg); - /* This chip has hardware problems that generates - * bogus PHY receive status so by default shut up the message. - */ - if (hw->chip_id == CHIP_ID_YUKON_FE_P && - hw->chip_rev == CHIP_REV_YU_FE2_A0) - sky2->msg_enable &= ~NETIF_MSG_RX_ERR; - /* Auto speed and flow control */ sky2->autoneg = AUTONEG_ENABLE; sky2->flow_mode = FC_BOTH; -- cgit v1.2.3