[vortex] full-duplex with 3c905

[Hamid Reza Shahriari]

Hi,
    I want to configure my 3c905 NIC in full-duplex mode.
I'm using 3c59x.c v0.99H in Linux 2.2.15 and a 3com Switch 3000
(SuperStack II).
I tried:
# modprobe 3c59x debug=1 full_duplex=1

and kernel message was:

3c59x.c:v0.99H 11/17/98 Donald Becker
http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html
eth0: 3Com 3c905 Boomerang 100baseTx at 0xdf00,  00:60:08:92:4b:af, IRQ
12
   8K word-wide RAM 3:5 Rx:Tx split, autoselect/MII interface.
   MII transceiver found at address 24, status 786f.
   Enabling bus-master transmits and whole-frame 
eth0: MII #24 status 786f, link partner capability 40a1, setting
full-duplex.

But by ping or netperf to others machines (full or half duplex) 
network speed decreases. (ping time increases from 0.1 to 0.6 ms.)

In normal 'modprobe 3c59x' kernel message is:

3c59x.c:v0.99H 11/17/98 Donald Becker
http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html
eth0: 3Com 3c905 Boomerang 100baseTx at 0xdf00,  00:60:08:92:4b:af, IRQ
12
   8K word-wide RAM 3:5 Rx:Tx split, autoselect/MII interface.
   MII transceiver found at address 24, status 786f.
   Enabling bus-master transmits and whole-frame receives.

What was wrong? Can my switch support full-duplex mode?

Thanks in advance,
--Hamid