[Soekris] net4501 with ff:ff:ff:ff:ff:ff MAC address

[b.candler@pobox.com]

OK, I can answer my own question now. 

Being in the fortunate position of having several net4501's here, I dumped 
the EEPROM from a working one: 

root at SBRouter:~# natsemi-diag -ee
natsemi-diag.c:v2.08 2/28/2005 Donald Becker (becker at scyld.com)
http://www.scyld.com/diag/index.html
Index #1: Found a NatSemi DP83815 adapter at 0xe000.
Natsemi 83815 series with station address 00:00:24:c2:c4:bc
Transceiver setting Autonegotation advertise 10/100 Mbps half and full 
duplex.
EEPROM address length 6, 64 words.
EEPROM contents (64 words):
0x00:  100b 0020 0b34 41f3 0000 0000 0000 0000
0x08:  6112 5e62 1905 aa3d ffff ffff ffff ffff
0x10:  ffff ffff ffff ffff ffff ffff ffff ffff
0x18:  ffff ffff ffff ffff ffff ffff ffff ffff
0x20:  ffff ffff ffff ffff ffff ffff ffff ffff
0x28:  ffff ffff ffff ffff ffff ffff ffff ffff
0x30:  ffff ffff ffff ffff ffff ffff ffff ffff
0x38:  ffff ffff ffff ffff ffff ffff ffff ffff
Decoded EEPROM contents:
PCI Subsystem IDs -- Vendor 0x100b, Device 0x0020.
PCI timer settings -- minimum grant 11, maximum latency 52.
Ethernet MAC Station Address 00:00:24:c2:c4:bc.
Wake-On-LAN password 00:00:00:00:00:00.
Transceiver setting 0x--f-: advertise 10/100 Mbps half and full duplex.
Flow control enabled.
EEPROM active region checksum read as aa3d, vs aa3d calculated value.
Index #2: Found a NatSemi DP83815 adapter at 0xe100.
Natsemi 83815 series with station address 00:00:24:c2:c4:bd
Transceiver setting Autonegotation advertise 10/100 Mbps half and full 
duplex.
EEPROM address length 6, 64 words.
EEPROM contents (64 words):
0x00:  100b 0020 0b34 41f3 0000 0000 0000 0000
0x08:  6112 5ee2 1905 aadd ffff ffff ffff ffff
0x10:  ffff ffff ffff ffff ffff ffff ffff ffff
0x18:  ffff ffff ffff ffff ffff ffff ffff ffff
0x20:  ffff ffff ffff ffff ffff ffff ffff ffff
0x28:  ffff ffff ffff ffff ffff ffff ffff ffff
0x30:  ffff ffff ffff ffff ffff ffff ffff ffff
0x38:  ffff ffff ffff ffff ffff ffff ffff ffff
Decoded EEPROM contents:
PCI Subsystem IDs -- Vendor 0x100b, Device 0x0020.
PCI timer settings -- minimum grant 11, maximum latency 52.
Ethernet MAC Station Address 00:00:24:c2:c4:bd.
Wake-On-LAN password 00:00:00:00:00:00.
Transceiver setting 0x--f-: advertise 10/100 Mbps half and full duplex.
Flow control enabled.
EEPROM active region checksum read as aadd, vs aadd calculated value.
Index #3: Found a NatSemi DP83815 adapter at 0xe200.
Natsemi 83815 series with station address 00:00:24:c2:c4:be
Transceiver setting Autonegotation advertise 10/100 Mbps half and full 
duplex.
EEPROM address length 6, 64 words.
EEPROM contents (64 words):
0x00:  100b 0020 0b34 41f3 0000 0000 0000 0000
0x08:  6112 5f62 1905 aa3c ffff ffff ffff ffff
0x10:  ffff ffff ffff ffff ffff ffff ffff ffff
0x18:  ffff ffff ffff ffff ffff ffff ffff ffff
0x20:  ffff ffff ffff ffff ffff ffff ffff ffff
0x28:  ffff ffff ffff ffff ffff ffff ffff ffff
0x30:  ffff ffff ffff ffff ffff ffff ffff ffff
0x38:  ffff ffff ffff ffff ffff ffff ffff ffff
Decoded EEPROM contents:
PCI Subsystem IDs -- Vendor 0x100b, Device 0x0020.
PCI timer settings -- minimum grant 11, maximum latency 52.
Ethernet MAC Station Address 00:00:24:c2:c4:be.
Wake-On-LAN password 00:00:00:00:00:00.
Transceiver setting 0x--f-: advertise 10/100 Mbps half and full duplex.
Flow control enabled.
EEPROM active region checksum read as aa3c, vs aa3c calculated value. 

I then modified natsemi-diag.c so that the "emergency-rewrite" option wrote 
these values, used it to rewrite the three EEPROMs and their MAC addresses: 

natsemi-diag -# 1 -E -H xx:xx:xx:xx:xx:xx -w
natsemi-diag -# 2 -E -H xx:xx:xx:xx:xx:xy -w
natsemi-diag -# 3 -E -H xx:xx:xx:xx:xx:xz -w 

and hey presto after a hard reboot it worked :-) 

Regards, 

Brian. 

 --- natsemi-diag.c.orig 2007-12-13 11:22:12.000000000 +0000
+++ natsemi-diag.c      2007-12-13 11:14:37.000000000 +0000
@@ -823,8 +841,9 @@ 

     if (set_hwaddr) {
             u16 backup_ee_contents[] = {
 -                       0x1385, 0xf311, 0x0b34, 0x41f3, 0x0000, 0x0000, 
0x0000, 0x0000,
 -                       0x0000, 0x0000, 0x1915, };
+                       /* MODIFIED TO MATCH GOOD SOEKRIS NET4501 */
+                       0x100b, 0x0020, 0x0b34, 0x41f3, 0x0000, 0x0000, 
0x0000, 0x0000,
+                       0x0000, 0x0000, 0x1905, };
             if (emergency_rewrite)
                     memcpy(new_ee_contents, backup_ee_contents,
                                sizeof backup_ee_contents);