Yeah- see this excellent collection:

ftp://ftp.netbsd.org/pub/NetBSD/misc/dec-docs/index.html



On Mon, 3 Jan 2000, Jeff Roberson wrote:

> I tried forcing the rev to 2, and commenting out that one line which it
> hangs on.  In both cases the kernel boots and detects all devices
> succesfully, but in both cases I get weird errors accessing devices on the
> PCI bus.  For instance, I can configure my nic, but I can not send any
> data through it.  Does any one have any pointers to documentation for this
> chipset?  And for these problems specifically?  I'm just poking around in
> the dark here.  I'm going to look through the freebsd source tomorrow to
> see if I can find anything particularly enlightening. 
> 
> Thanks,
> Jeff
> 
> On Mon, 3 Jan 2000, Matthew Jacob wrote:
> 
> > Date: Mon, 3 Jan 2000 22:44:27 -0800 (PST)
> > From: Matthew Jacob <mjacob@feral.com>
> > To: Jeff Roberson <nomad@nop.aliensystems.com>
> > Cc: port-alpha@netbsd.org
> > Subject: Re: More pyxis/500a info..
> > 
> > 
> > Ummm- the same trick is used in a number of places- it may be that we all
> > die here because we're fooling with CIA setup that the prom is using, but
> > I'm a bit rusty at this end of the code for NetBSD to know for sure.
> > 
> > There've been a lot of unexplained issues/problems with a lot of this
> > goop- I'll be looking at the 8200 breakage this week or next (finally) to
> > try and fix that end of it.
> > 
> > Have you tried commenting this code out (i.e., forcing the rev to > 1)?
> > 
> > On Mon, 3 Jan 2000, Jeff Roberson wrote:
> > 
> > > So I found out the exact line that my machine hangs on.  It's in
> > > cia_dma_init (cia_dma.c) at aproximately line 215.  The line reads:
> > >  
> > >                REGVAL(CIA_PCI_W2BASE) = CIA_PYXIS_BUG_BASE |
> > >                     CIA_PCI_WnBASE_SG_EN | CIA_PCI_WnBASE_W_EN;
> > >  
> > > I found this simply by adding printf's here and there around suspicious
> > > portions of code.  Interestingly enough, if I comment this out the kernel
> > > boots, but I don't know how reliable it is.  I'll try installing from this
> > > kernel in a bit.  Anyway, would anyone care to guess at why this causes my
> > > machine to hang?
> > > 
> > > Thanks,
> > > Jeff 
> > > 
> > 
> > 
>