Есть железка на i.mx233 и по ряду причин желание загрузиться по nfs.

карточка на ASIX AX88772.

Linux version 2.6.31-626-g602af1c (andysm@debian-dell-d630) (gcc version 4.1.2) #38 PREEMPT Sat Mar 12 12:35:35 MSK 2011
Kernel command line: -e noinitrd console=ttyAM0,115200 root=/dev/nfs nfsroot=172.17.8.80:/home/andysm/work/ltib/rootfs rw ssp1=spi1 ip=172.17.8.178 gpmi

кусок лога...

TCP cubic registered
NET: Registered protocol family 17
RPC: Registered udp transport module.
RPC: Registered tcp transport module.
mxs-rtc mxs-rtc.0: setting system clock to 1970-01-01 00:11:59 UTC (719)
usb 1-1: new high speed USB device using fsl-ehci and address 2
usb 1-1: configuration #1 chosen from 1 choice
IP-Config: No network devices available.
eth0: register 'asix' at usb-fsl-ehci-1, ASIX AX88772 USB 2.0 Ethernet, 00:80:c8:3c:30:41
Looking up port of RPC 100003/2 on 172.17.8.80
rpcbind: server 172.17.8.80 not responding, timed out
Root-NFS: Unable to get nfsd port number from server, using default
Looking up port of RPC 100005/1 on 172.17.8.80
rpcbind: server 172.17.8.80 not responding, timed out
Root-NFS: Unable to get mountd port number from server, using default
Root-NFS: Server returned error -5 while mounting /home/andysm/work/ltib/rootfs
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "nfs" or unknown-block(2,0)
Please append a correct "root=" boot option; here are the available partitions:
1f00 40960 mtdblock0 (driver?)
1f01 1007616 mtdblock1 (driver?)
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)

Понятно что карточка появляется после попытки инициализации сети.
Вопрос как это победить. (При загрузке с SD того же ядра сетка работает.)

Добавить в строку загрузки параметр:
ipconfdelay=<sec>, where <sec> is the number of seconds to delay before attempting to configure the Ethernet adaptor.

UPD http://kerneltrap.org/mailarchive/linux-ne.../6271694/thread

Спасибо большое.
после патча заработало.