[PATCH 2/3] powerpc/85xx: Provide two functions to save/restore the core registers

Dongsheng.Wang at freescale.com Dongsheng.Wang at freescale.com
Thu Jan 23 13:49:09 EST 2014

> > >
> > > The whole point of calling enable_kernel_fp() in C code before
> > > suspending is to ensure that the FP state gets saved.  If FP is used
> > > after that point it is a bug.  If you're worried about such bugs, then
> > > clear MSR[FP] after calling enable_kernel_fp(), rather than adding
> > > redundant state saving.
> > >
> >
> > enable_kernel_fp() calling in MEM suspend flow.
> > Hibernation is different with MEM suspend, and I'm not sure where will call
> this
> > interface, so we need to ensure the integrity of the core saving. I don't
> think
> > this code is *redundant*. I trust that the kernel can keep the FP related
> > operations, that's why a judgment is here. :)
> For hibernation, save_processor_state() is called first, which does
> flush_fp_to_thread() which has a similar effect (though I wonder if it's
> being called on the correct task for non-SMP).
Yes, thanks, I miss this code.:)

But I still think we need to keep this judgment, because i provide an API.
If you still insist on I can remove *FP*, but I don't want to do this..:)

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