Re: Q: double Boot for SMP 7300
>I think that the answer to the original question is that when
>booting from BootX, you have to have a kernel that supports SMP, but
>the stock kernel does not, so you have to build your own, and put it
>where BootX can find it.
>
>I don't think there is anything that you need to do to your PRAM,
>whatever that is, or your nvram, if you are using BootX. I use
>BootX on my dual processor machine, it works fine, and I have never
The problem is more nasty. With the "old" MP mecanism (Apple/Daystar),
the kernel cannot take over the second CPU if MacOS already started it.
It was not a problem until MacOS 8.6 or so. At this point, Apple changed
MacOS nanokernel to be fully SMP and now starts the second CPU early during
boot, long before BootX takes over.
miBoot still works as it is started before the RAM-based nanokernel (out of
the ROM-based one which is still the old one).
I may have a way to work around the problem from BootX by sending an interrupt
to the second CPU to force it to reach the interrupt vector (provided
that MacOS
leaves it running with MSR:EE enabled). However, this would require some
hacking
I don't have the corresponding hardware to do.
Ben.
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