On Tue, 12 Nov 2002, Jonathan Towne wrote:

> as noted in the subject, I need a stripped-down kernel compiled to
> get my vax working, it only has 4meg of RAM, and this seems to pose
> a problem, as I can't even get a netboot-install running.
>
> the only version I can really do all of this with that I've tried
> is 1.3.2, now, in reality, I don't mind running 1.3.2, but it
> would be nice to use 1.5.3 instead, the 1.6 MOP loader seems
> just plain broken, if anyone is interested, say so and I'll try
> it again and paste the errors in another thread.

Ah, indeed.  It looks like the bootloader in the 1.6 release,
<ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-1.6/vax/installation/netboot/boot>
has not been made moppable.

A release engineering oversight, and maybe related to the fact that 1.6
has replaced the `mopa.out' tool with `mopcopy'?  The new tool supports
converting ELF binaries to MOP; the bootloader is now being compiled ELF
instead of a.out... But, having just run `mopcopy' on that image using
my VAX results in a 67MB mop image of a 64KB bootloader. That can't be
good!  I wondered why it was taking so long.

> regardless, if anyone can do this for me, I could probably supply
> a kernel config file for the machine.. (having never done this
> for a vax ...) and we'll see if it works (?);
>
> alternatively, if anyone could give an explanation, in great
> detail, how I would cross-compile a vax kernel on my 1.5.3
> sparc (ss2) machine.. another interesting thing I'd like to
> learn to do, but maybe another day.

No need to resort to a cross-compile, necessarily.  Do you have a
fairly modern Linux or NetBSD PC system hanging around?  You could
install NetBSD/vax 1.5.3 on it under the SIMH emulator:

  http://www.netbsd.org/Ports/vax/emulator-howto.html

Alternatively, I can try compiling up a 1.5.3 kernel for you on my 1.6
system.  I believe that should work fine, though I've never actually
tried to compile a kernel for a release previous to the one on which my
system runs.  It may take another day; my MicroVAX 3100's batch queue is
loaded with a half dozen package compiles.

-brian.