[tulip] 21140 and Interrupt Mitigation?

[Roisman, Dani]

Greetings I have 3 simple questions.  First the data:

I have old netgear FA310TX cards that use DEC 21140 chipsets:

eth1: Digital DS21140A Tulip rev 34 at 0xb800, 00:40:05:41:84:73, IRQ 10.
eth1:  EEPROM default media type Autosense.
eth1:  Index #0 - Media MII (#11) described by a 21140 MII PHY (1) block.
eth1:  MII transceiver #0 config 1000 status 782d advertising 01e1.
tulip.c:v0.92t 1/15/2001  Written by Donald Becker <becker@scyld.com>

I recently upgraded to v0.92t, and unsuccessfully tried to force interrupt
mitigation:

# /sbin/mii-diag eth1 -G 0x8b240000
SIOCSPARAMS on eth1 failed: Operation not supported

I am, however, seeing these log entries:

May 11 19:25:01 soewfv2 kernel: eth1: Too much work during an interrupt,
csr5=0xfc630040. 
May 11 19:25:01 soewfv2 kernel: eth1: Too much work during an interrupt,
csr5=0xfc6980c4. 
May 11 19:25:10 soewfv2 kernel: eth1: Restarted Rx at 1821234174 /
1821234174. 
May 11 19:25:10 soewfv2 kernel: eth1: Too much work during an interrupt,
csr5=0xfc0988c7. 
May 11 19:25:10 soewfv2 kernel: eth1: Restarted Rx at 1821234174 /
1821234174. 
May 11 19:25:16 soewfv2 kernel: eth1: Too much work during an interrupt,
csr5=0xfc6f0040. 
May 11 19:25:16 soewfv2 kernel: eth1: Too much work during an interrupt,
csr5=0xfc6988c5. 
May 11 19:25:25 soewfv2 kernel: eth1: Restarted Rx at 1821278087 /
1821278087. 
May 11 19:25:25 soewfv2 kernel: eth1: Too much work during an interrupt,
csr5=0xfc0988c7. 
May 11 19:25:25 soewfv2 kernel: eth1: Restarted Rx at 1821278087 /
1821278087. 

Questions:
1) Should I be concerned with the "Too much work" message?  What does it
really mean?

2) Should I be concerned with the "Restarted Rx" message? What does it
really mean?

3) Is Interrupt Mitigation even supported on this card?  If yes, how do I
force it on?

----
Dani Roisman
droisman@station.sony.com