Jason R. Thorpe <thorpej@zembu.com> asked;

> sd0(xasc0:0:0:0): xasc0: timed out [ecb 0x80991000 (flags 0x1, dleft 2c, stat 0)], <state 5, nexus 0x80991000, phase(l 1, c 1, p 1), resid 2c, msg(q 0,o 80) DMA active>
> sd0(xasc0:0:0:0): xasc0: timed out [ecb 0x80991000 (flags 0x41, dleft 2c, stat 0)], <state 5, nexus 0x80991000, phase(l 1, c 1, p 1), resid 2c, msg(q 20,o 80) DMA active> AGAIN
>
> Anyone have any idea why those happen before mounting the root FS?  Full
> dmesg below.

Triggered by the async nature of your RZ57 disk drive, I suspect.

My MAXINE has 7 RZ28 disks on PMAZ TC option card.  Excerpt from dmesg is;

NetBSD 1.5V (MAXINE) #0: Tue May  8 13:28:54 JST 2001
    nisimura@build:/usr/src/sys/arch/pmax/compile/MAXINE
Personal DECstation 5000/25 (MAXINE)
...
xasc0 at ioasic0 offset 0x300000: NCR53C94, 25MHz, SCSI ID 7
scsibus0 at xasc0: 8 targets, 8 luns per target
...
xasc1 at tc0 slot 1 offset 0x0: NCR53C94, 12MHz, SCSI ID 7
scsibus1 at xasc1: 8 targets, 8 luns per target
...
scsibus0: waiting 2 seconds for devices to settle...
sd0 at scsibus0 target 0 lun 0: <QUANTUM, LPS540S, 590S> SCSI2 0/direct fixed
sd0: 516 MB, 2740 cyl, 4 head, 96 sec, 512 bytes/sect x 1057616 sectors
sd0: Sync (200.0ns offset 8), 8-bit (5.000MB/s) transfers
scsibus1: waiting 2 seconds for devices to settle...
sd1 at scsibus1 target 0 lun 0: <DEC, RZ28     (C) DEC, 442D> SCSI2 0/direct fixed
sd1: 2007 MB, 3045 cyl, 16 head, 84 sec, 512 bytes/sect x 4110480 sectors
sd1: Sync (416.0ns offset 15), 8-bit (2.403MB/s) transfers
sd2 at scsibus1 target 1 lun 0: <DEC, RZ28     (C) DEC, D41C> SCSI2 0/direct fixed
sd2: 2007 MB, 3045 cyl, 16 head, 84 sec, 512 bytes/sect x 4110480 sectors
sd2: Sync (416.0ns offset 15), 8-bit (2.403MB/s) transfers
...

MAXINE TC is clocked at the half rate of 12.5MHz and that's the reason
why transfer parameters differ from builtin IOASIC SCSI.  I've no
trouble to run disklabel(8), newfs(8) and iozone on the fresh RZ28
disks so far.  The write performance is just horrible, but it's
another story.

Tohru Nishimura