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Re: Supported Hardware ?

Le 25/10/2016 06:19, Lennart Sorensen a écrit :
That one would be powerpcspe, not powerpc, unless I have misunderstood
the e500v2.  e300, e500mc, e5500 and e6500 are all normal sane powerpc
designs, while e500v1 and e500v2 are the SPE chips that don't have normal
powerpc FPUs.

Whyever would they be playing with that chip?  I would expect them to
hit software compatibility problems.

I suppose since AmigaOS never really did worry about FPU (most Amigas
never had one), a powerpc build that doesn't use the FPU much would
run on either, and they could even use math libraries (which I seem to
recall AmigaOS always did anyhow) to hide the difference in architecture
of the hardware.

The only way I see they could be running Debian on that board, is with
a custom built kernel with MATH_EMULATION enabled.  That might be what
they have done.  I do see one of the blog pages running powerpcspe on
it instead, which makes more sense.


This is something I've been testing for years on SBCs with Freescale MPC8540 and MPC8548E.

MPC8540 (e500v1): the kernel must be compiled with -mcpu=8540 (with math emul of course); compiled for generic powerpc, even with math emul, it doesn't run. Then Debian for Powerpc runs OK. Means the illegal FP instructions which are trapped by kernel math emulation are the generic ppc FP instructions, not the e500v2. Those have been running in production for years.

MPC8548E (e500v2): compiling the kernel is no problem, but of course Debian for Powerpc doesn't work, and math emul is impossible. The only way is the powerpcspe port. Didn't exist when I needed it and I gave up.


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