Hi,

I tried to add an Adaptec 1542B to a pc I hope to
use as a cpu server (to support DAT and CDROM drives)
and I get a panic (This is a dual Pentium Pro machine,
though I still have *nomp=1).

I have an ata disk but this is for swap.

I am booting the current installation floppy - but
I guess it must have an aha1542 driver as its doing
somthing!

Without the scsi0=aha1542 port=0x330 in plan9.ini
the machine boots fine.

The error I get is:

    panic: what ? up is zero pc 0x801a413d
    ktrace /kernel/path 80106720 800005c50
   <stack dump...>

I cannot see this error in ther kernel though there is
somthing similar in trap.c - maybe the error message
is getting overwritten by somthing else?

The card is setup for its default configuration from the adaptec manual
(apart from the BIOS and floppy being disabled, and the DMA
speed of 8MB/s) IE port=0x330 dma=5 irq=11.

Looking at the source (below) I wonder if the interrupt structure
has changed a bit since this code was written and the kernel
is more strict about stray interrupts than it used to be?

This is purely a guess. anyone any other / more concrete ideas?

ioalloc and irqalloc attached - BTW I get an error when I cat'ed
these devices: qlock 80186a14 nlocks 1. Dont know if this is relevant.
also the ports reported in /dev/sdstat don't tally with those in
/dev/ioalloc...

-Steve

sdmylex.c:
/*
  * Get the id, DMA and IRQ info from the board. This will
  * cause an interrupt which will hopefully not cause any
  * trouble because the interrupt number isn't known yet.
  * This is necessary as the DMA won't be set up if the
  * board has the BIOS disabled.
  *
  * If the IRQ is already known, this must be a 32-bit PCI
  * or EISA card, in which case the returned DMA and IRQ can
  * be ignored.
  */