On Apr 4, 2005, at 9:57 PM, Tim Kelly wrote:

> On Mon, 4 Apr 2005 21:35:55 -0400
> Michael <macallan18@earthlink.net> wrote:
>
>>
>> What kind of card is it ( besides sitting in the L2 slot ) - does it
>> need any additional software to be recognized by MacOS? If so - does
>> it leave anything funny in OF's nvramrc or something like that? If
>> you're lucky this thing can be enabled with some OF voodoo ( Tim?
>> You're the OF guru. )
>
> Dan LaBell clearly knows more than I do about OF and Forth. I do know
Maybe, forth, but as far as the mac specific voodoo, I think you do.
And openfirmware is ANS forth, while I learned Forth-83.
The docs for sparc claim that they have switch-cpu, doesn't look like 
we do though.  Maybe try:
   show-devs /cpus
Also try:
   sifting cpu
One standout in the list is find-unused-cpu, also noticed a start-cpu1.


> that OF does expect to be on one CPU only, so I don't think it's set up
> to switch CPUs. I have a 7200 that used to have a Sonnet G3 upgrade 
> card
> (which was horribly unreliable) and as far as I could tell, the switch
> to the PCI card-based CPU only occured after the extension was loaded
> by MacOS. If I had to guess, there has to be some write to a PCI
> register that then turns the CPU on, and from there some renegotiation
> of PCI bus mastering occurs or something that allows the second CPU to
> become the primary one. The new CPU gets the same register contents as
> the old one and resumes execution of the OS. Sort of a fork of the OS,
> with the parent then turning off external interrupts on the old CPU.
>
What came with the upgrade in question?  An extension ? Or a firmware 
patch?
If firmware, maybe they just patched mac-boot...