[vortex] 3c905C: No MII transceiver present / 10 Mbit, half
duplex, no link
Donald Becker
becker@scyld.com
Wed Oct 8 22:26:01 2003
On Wed, 8 Oct 2003, Bogdan Velcea wrote:
> I have 2 ethernet cards 3Com905C (Tornado), that gives me some headaches:
> 1. sometimes the cards negotiate to Half-Duplex instead of Full-Duplex ( even if
> a changed the cables, or the switch ), in random situations ( and sometimes on
> huge amount of traffic ):
>
> 2. the utility from linux, named "mii-tool" gives me wrong informations about
> the status of my ethernet cards ( I asure you that my Cisco Switch tells me that
> both NICs are on auto-100 auto-FD !):
>
> # mii-tool
> eth0: 10 Mbit, half duplex, no link
> eth1: 10 Mbit, half duplex, no link
What driver version are you using?
> 3. the utility "mii-diag" ( that I found on Scyld FTP site:
> ftp://ftp.scyld.com/pub/diag/mii-diag.c with
> ftp://ftp.scyld.com/pub/diag/libmii.c ) seems to not know the MII settings of my
> NICs:
>
> # mii-diag eth0
> Basic registers of MII PHY #0: 0000 0000 0000 0000 0000 0000 0000 0000.
> No MII transceiver present!.
The 'mii-diag' program is telling you that the driver isn't reporting a
transceiver.
> # ./mii-diag --force eth0
> Basic registers of MII PHY #0: 0000 0000 0000 0000 0000 0000 0000 0000.
> No MII transceiver present!.
> Basic mode control register 0x0000: Auto-negotiation disabled, with
> Speed fixed at 10 mbps, half-duplex.
Notice that this is the same as the 'mii-too' report, except that
'mii-diag' told you the status was bogus.
> 4. the "vortex-diag" utility ( from the sime site ) gives me some good
> information, but not that I'm interested ( like Link-State ), and strange
> informations like "MAC settings: half-duplex":
...
> MII PHY found at address 24, status 782d.
> MII PHY 0 at #24 transceiver registers:
> 1000 782d 0040 6176 0101 41e1 0003 0000
Errrkkk.
> Transceiver selection: 100baseTX.
> Options: negotiated duplex, link beat required.
Hmmm, did you change the configuration EEPROM from the default?
What was the driver detection message?
> Index #1: Found a 3c905C Tornado 100baseTx adapter at 0xe800.
..
> Transceiver selection: 100baseTX.
> Options: force full duplex, link beat required.
Again, this is not the default configuration EEPROM setting!
> MII PHY found at address 24, status 782d.
> MII PHY 0 at #24 transceiver registers:
> 1000 782d 0040 6176 05e1 41e1 0003 0000
Yet the driver negotiated anyway...
> 6. I forgot to say that I tryed even to force the settings with this utilities
> and/or with "modprobe 3c59x full_duplex=1 options=4" !
Don't do that! Forcing full duplex or forcing the transceiver setting
is almost always incorrect.
--
Donald Becker becker@scyld.com
Scyld Computing Corporation http://www.scyld.com
914 Bay Ridge Road, Suite 220 Scyld Beowulf cluster system
Annapolis MD 21403 410-990-9993