On Fri, Feb 26, 1999 at 12:20:16PM -0700, Justin T. Gibbs wrote:
> >thanks for the info Bill, I'll see what I can dig up when I get home.  The
> >annoying this is, there was an Adaptec AIC7xxx mailing list at one time
> >(circa 95-97) which is now AWOL it seems.  I even got a hit on a post
> >entitled "Re: # of SCBs" which I can't find.  ack!  :)
> 
> Try aic7xxx@FreeBSD.org.
> 
> My first guess at this problem would be some issue with how the chip
> is mapped in, causing the software to fail when attempting to access
> the on-chip SCB space.
> 
> --
> Justin
> 

It does seem to be a problem with how the chip is mapped in;  I wasn't
able to work on this for a bit because of the bootblock problems (wanted
to use a serial console), but I've been poking around for the last couple
of days.  Most of my time has been spent learning how to set up gdb via
serial, but now it's working great.

Anyway, I compiled a kernel with AHC_DEBUG set, and got this:

ahc1 at pci0 dev 11 function 0
ahc1: interrupting at irq 11
ahc1: Reading SEEPROM...checksum error
ahc1: No SEEPROM availible
ahc1: Using left over BIOS settings
ahc1: aic7880 Wide Channel, SCSI Id=7, 1 SCBs
ahc1: hardware scb 26 bytes; kernel scb 2148 bytes; ahc_dma 8 bytes
ahc1: Resetting Channel A
NEEDSDTR == 0xb
NEEDWDTR == 0xa
DISCENABLE == 0xffff
ahc1: Downloading Sequencer Program...Done
scsibus0 at ahc1 channel 0: 16 targets, 8 luns per target

[crash]


I also loaded FreeBSD 3.1 on the system as a test;  it seems to work OK.
Not to disparage FreeBSD, NetBSD's what I've got on all my other systems,
and by gum, I'd like it here!   So, the hardware itself seems OK.  Just
in case it triggers anything for anyone, here's what a FreeBSD kernel
with AHC_DEBUG says (though I had to edit some stuff out, as it didn't
compile cleanly with AHC_DEBUG):

ahc0: <Adaptec aic7880 Ultra SCSI adapter> rev 0x00 int a irq 11 on pci0.11.0
ahc0: aic7880 Wide Channel A, SCSI Id=7, 16/255 SCBs
ahc0: hardware scb 64 bytes; kernel scb 32 bytes; ahc_dma 8 bytes
DISCENABLE == 0xffff
ULTRAENB == 0xffff



...I got all excited when I saw the difference in the "hardware scb" line,
before I realized it's just the size of internal data structures.

So, anyway, I'm at the point now where I'm slowly sifting through the 
attachment of the ahc device using GDB, but I'm afraid my skills might
not be up to the task.  Anyone got any further pointers of what I might
look at?


Thanks in advance,
+j


-- 
Jeff Rizzo                                         http://boogers.sf.ca.us/~riz