How do I disable the cache?

Thanks,
Chris.
ccraft@cncc.cc.co.us

Gunnar Helliesen wrote:
> 
> Chris Craft wrote:
> >
> > Here's what I get with the netbsd kernel from subzero:
> > //some chopping//
> > NetBSD 1.3G (GENERIC) #760: Fri Aug 28 23:47:43 CEST 1998
> >     ragge@vs4000:/usr/src/sys/arch/vax/compile/GENERIC
> >
> > VAXstation 3100/m76
> > realmem = 12447744
> > avail mem = 9375744
> > Using 151 buffers containing 618496 bytes of memory.
> > backplane0 (root)
> > cpu0 at backplane0: KA43
> > memory error!
> > primary cache status: panic: ptelen fault in system space: addr panic
> > ptelen fault in system space ...et cetera for a few lines then...
> > ?24 UNXINT 00BDF281 040A0000 054
> 
> Hm, looks familiar...
> 
> > Is this a hardware problem? The test kernel netbsd.test also fails but
> > not quite the same way due to a memory error, primary cache status:
> > 1228<BCHIT,DPERR,INTR,REFRESH>, secondary cache status:
> > ffe1<TPE,DPE,MISS,ENABLE> three times, then a panic: ptelen fault in
> > system space: addr 0 pc 0, syncing disks... done
> 
> I have been having problems getting a uVAX 3300 to boot _any_ version of
> NetBSD. The hardware is known good, i.e. it boots and runs VMS just
> fine. When I try to boot NetBSD the kernel crashes with almost the same
> error that you're reporting:
> 
> cpu0 at backplane0: KA640, CVAX microcode rev 4 Firmware rev 83
> panic: ptelen fault in system space: addr 0 pc 0
> syncing disks... done
> 
> ?06 HLT INST
>         PC = 800A8121
> 
> The netbsd.test kernel was made by Ragge for me to test on my 3300 and
> see exactly where it crashes. From the results Ragge concluded that the
> kernel crashes as it tries to enable the level-2 cache.
> 
> This information may or may not apply to your problem. As others seem to
> boot M76's with 1.3.2 successfully I think perhaps you should consider
> the possibility that you may have corrupt cache in your machine. Perhaps
> you should try booting a kernel with all caches disabled?
> 
> Gunnar
> 
> --
> Gunnar Helliesen   | Bergen IT Consult AS  | NetBSD/VAX on a uVAX II
> Systems Consultant | Bergen, Norway        | '86 Jaguar Sovereign 4.2
> gunnar@bitcon.no   | http://www.bitcon.no/ | '73 Mercedes 280 (240D)