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Message-ID: <1426276250.27998.6.camel@freescale.com>
Subject: Re: [PATCH 1/2] powerpc: Add a proper syscall for switching endianness
From: Scott Wood <scottwood@freescale.com>
To: Michael Ellerman <mpe@ellerman.id.au>
Date: Fri, 13 Mar 2015 14:50:50 -0500
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Cc: linuxppc-dev@ozlabs.org, Jeremy Kerr <jk@ozlabs.org>
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On Fri, 2015-03-13 at 17:38 +1100, Michael Ellerman wrote:
> On Fri, 2015-03-13 at 15:39 +1100, Michael Ellerman wrote:
> > We currently have a "special" syscall for switching endianness. This is
> > syscall number 0x1ebe, which is handled explicitly in the 64-bit syscall
> > exception entry.
> > 
> > diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
> > index 91062eef582f..c3ee21a1d9cf 100644
> > --- a/arch/powerpc/include/asm/systbl.h
> > +++ b/arch/powerpc/include/asm/systbl.h
> > @@ -367,3 +367,4 @@ SYSCALL_SPU(getrandom)
> >  SYSCALL_SPU(memfd_create)
> >  SYSCALL_SPU(bpf)
> >  COMPAT_SYS(execveat)
> > +PPC_SYS(switch_endian)
> 
> And of course I forgot about 32-bit.
> 
> According to Paul there are no working implementations of LE on 32-bit cpus, so
> the syscall doesn't really make sense there.
> 
> Scott does that sound right to you for FSL stuff?

We don't support LE on FSL chips.

-Scott