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 <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 0792031..a3de0b6 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -2148,6 +2148,18 @@
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 @@
/* 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 @@
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 @@
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;