[tulip] strange speed&duplex? (accton en 2242)

[Donald Becker]

On Tue, 10 Apr 2001, Erik Steffl wrote:

>   how do I verify the speed & HD/FD of tulip card (accton en2242). AFAIK
> it's capable of full duplex 100Mbps, but it only show half duplex and I
> have no idea what speed is. Is there any way to verify? some network
> benchmarks that would measure real performance?

>   here's what I get from diag tools:

He ran the diag tools -- Good!

> # ./mii-diag 
> Using the default interface 'eth0'.
> Basic registers of MII PHY #1:  1000 786d 0022 5410 01e1 40a1 0005 2801.
>  Basic mode control register 0x1000: Auto-negotiation enabled.
>  You have link beat, and everything is working OK.
>  Your link partner advertised 40a1: 100baseTx 10baseT.

Your link partner is a half duplex bridged repeater.
It cannot do full duplex.
If you force full duplex, you will have very bad performance.

The new version of 'mii-diag' calculates the speed and duplex for you.
With the older versions you have to manually interpret the highest
common capability.

> # ./tulip-diag 
> tulip-diag.c:v2.07 3/31/2001 Donald Becker (becker@scyld.com)
>  http://www.scyld.com/diag/index.html
> Index #1: Found a Accton EN1217/EN2242 (ADMtek Comet) adapter at 0x1c00.
>  Comet duplex is reported in the MII status registers.

Take careful note of this message!

>   or '-m' or '-mm' to show MII management registers.

Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Second Generation Beowulf Clusters
Annapolis MD 21403			410-990-9993