On Thu, 03 May 2012 20:06:11 +0200
Niccolò Belli [off-list ref] wrote:

Il 03/05/2012 17:23, Stephen Hemminger ha scritto:

quoted

The receiver on some versions of the chip can't keep up with full speed
of 1G bit/sec. The receive  FIFO has hardware issues, and since I don't
work for Marvell, working around the problem is guesswork. Without exact
information all that can be done is have a timeout and blunt force reset
logic. The vendor driver sk98lin has the same brute force logic, but may
just not print the message.

If I lower the speed to 100Mb/s I don't have rx errors anymore *BUT* 
when using dhcp after a while the network doesn't work anymore:

64 bytes from 8.8.8.8: icmp_req=590 ttl=47 time=61.7 ms
64 bytes from 8.8.8.8: icmp_req=591 ttl=47 time=62.0 ms
64 bytes from 8.8.8.8: icmp_req=592 ttl=47 time=62.0 ms
ping: sendmsg: Network is unreachable
ping: sendmsg: Network is unreachable
ping: sendmsg: Network is unreachable


I have no problems with dhcp using wifi or other NICs.

Niccolò

Maybe ethtool registers have some info?

# ethtool -S eth0
NIC statistics:
     tx_bytes: 3640274
     rx_bytes: 61588953
     tx_broadcast: 641
     rx_broadcast: 9964
     tx_multicast: 126
     rx_multicast: 1501
     tx_unicast: 32683
     rx_unicast: 50415
     tx_mac_pause: 0
     rx_mac_pause: 0
     collisions: 0
     late_collision: 0
     aborted: 0
     single_collisions: 0
     multi_collisions: 0
     rx_short: 0
     rx_runt: 0
     rx_64_byte_packets: 8704
     rx_65_to_127_byte_packets: 4414
     rx_128_to_255_byte_packets: 6218
     rx_256_to_511_byte_packets: 1289
     rx_512_to_1023_byte_packets: 1777
     rx_1024_to_1518_byte_packets: 39478
     rx_1518_to_max_byte_packets: 0
     rx_too_long: 0
     rx_fifo_overflow: 0
     rx_jabber: 0
     rx_fcs_error: 0
     tx_64_byte_packets: 1628
     tx_65_to_127_byte_packets: 27483
     tx_128_to_255_byte_packets: 2885
     tx_256_to_511_byte_packets: 637
     tx_512_to_1023_byte_packets: 429
     tx_1024_to_1518_byte_packets: 388
     tx_1519_to_max_byte_packets: 0
     tx_fifo_underrun: 0


And if you enable the debugfs option there is more info
hidden there.

# mount -t debugfs debugfs /sys/kernel/debug
# cat /sys/kernel/debug/sky2/eth0