MPC8540 : What's "SPE used in kernel" ?

[Johannes Berg]

> I wonder why a kernel configured for E500 and compiled by a E500-specific gcc
> triggers this message.  Is it invalid to use SPE instructions in the kernel 
> or do I misunderstand the message ?

I think it's like floating point/altivec, we don't always save the FP
registers on kernel/userspace transitions and so have to explicitly save
them to use them in the kernel, otherwise we'd clobber the userspace
register state.

I guess there's something like kernel_enter_spe()?

johannes
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