Subject: Re: Booting from 2940UW Controller
To: NetBSD <firstname.lastname@example.org>
From: Donald Lee <email@example.com>
Date: 04/27/2001 08:20:02
Let me weigh in with some information.
The 2940UW flashers that are probably available to you are:
v 3.0 - no open firmware
v 4.1 "A/V"
v 4.1 "standard"
The difference between the AV and non-AV versions, as I understand it, is
that there were some bugs in Apple's Open Firmware that did not
allow us to do the Open Firmware in the A/V PowerMacs. As I recall,
the non-AV version would work on the "newer" machines, which at the time
was the B&W G3s, which _required_ OF for bootability. The A/V version was
created to work around bugs in some subset of PMacs that were loosely
characterized as A/V. I believe that the A/V version did *not*
have OF, but relied on the MacOS ROMs to load the driver.
The Open Firmware on the 2940UW has not been updated since 4.1, and
the most recent cards have OF based on the 2940UW. The more recent
cards have had to be fixed to repair various OF bugs in Adaptec's
OF. The fixes were required on the newer machines so that stuff like
Apple's "picker" would work. It does not surprise me that the 2940UW
does not work to boot NetBSD. That OF was built and tested only with
MacOS in mind, although the authors *thought* they wrote it properly
and so that it was correct and complete, MacOS was the only test vehicle
It is not likely that the 2940UW for Macintosh will get a rev any time
I hope this is helpful.
At 11:13 PM -0500 4/24/01, Michael Wolfson wrote:
>At 9:57 PM -0700 4/23/01, James Tuman Nelson wrote:
>:)Let me guess: because I have a 7500, I have to use the AV version of
>:)v4.1 for flashing the 2940, regardless of whether the machine was
>:)configured with AV or not when purchased. Thus, I will not be able to
>:)use the 2940UW to boot, unless some sort of new development comes about,
>:)or I procure a nonAV machine, such as a G4.
>That is how I read the Adaptec install notes. And, since I don't have
>access to a non-"A/V" mac, I'm hesitant to flash my 2940 in case something
>goes wrong. The term "A/V" is wholly Adaptec's, and has nothing to do with
>whether there are A/V capabilities or not on youre model. AFAICT, they
>were referring to the first generation of PCI powermacs.
>:)However, when I look at the words and .properties, they are identical
>:)for both AV and non-AV versions! Further, the number of bytes is
>:)identical. It is as though both flash programs are identical. I will
>:)check sources of these firmware flashes.
>That's a bit weird. Maybe it's just the part of the program that flashes
>it is different on different models.
>:)So, how would one set up a floppy or Jaz disk to boot the kernel and
>:)then mount the 2940 scsi drive root, /usr, and so forth partitions?
>Using the boot floppy, install onto your drive attached to the adaptec bus
>disklabel and create a filesystem on your Jaz disk
>copy the kernel over to the Jaz
>run installboot on the Jaz to install the bootloader
>Now, you'd type:
>boot /path/to/Jaz -a
>and once the kernel is loaded, you specify that the filesystems are located
>on your adaptec drive
>Once you're happy with this, you can compile a new kernel with the
>adaptec-based hard drive hard wired in as the root partition (you probably
>also want a copy of the kernel in the root level of your adaptec-based
>drive so 'top' and 'ps' work)
>Let me know if you need more detailed instructions.
>:)Are you able to boot from your 2940?
>No, I'm not. I've just been using a drive on the external slow-narrow bus
>:)I suppose I could set up a root device on an external scsi Jaz drive
>:)and just use the 2940 device as /usr, /var, /home, /work, and so forth,
>:)but that is kind of crude. Plus, I lose access to the Jaz.
>No, you could remove the Jaz once the kernel is loaded. Only the
>bootloader looks at that filesystem.
>:)I will move my 2940UW to the other end of the PCI expansion bus and see
>:)if that changes anything.
>That should make no difference -- Adaptec never provided the support you're
>looking for on this model of SCSI adapters in your model of mac.
> -- MW