[PATCH] Set cpu explicitly in kernel compiles

Kumar Gala kumar.gala at freescale.com
Sat May 7 01:47:14 EST 2005

On May 6, 2005, at 9:53 AM, Tom Rini wrote:

> On Fri, May 06, 2005 at 04:44:33PM +0200, Segher Boessenkool wrote:
>  > >Well, say you are compiling for 405.  You either need to have a gcc
>  > >that was configured with --with-cpu=405, or you need to have hacked
>  > >arch/ppc/Makefile to add -mcpu=405.  In both cases the problem 
> doesn't
>  > >arise.  It only arises if you have a biarch gcc4 that was 
> configured
>  > >without any --with-cpu=xxx option and is run without any -mcpu=xxx
> > >option.
>  >
> > It happens for any installation where the default chosen by the GCC
>  > used is not the -mcpu=XXX flag you need used for your kernel.  Which
>  > is a much more general statement than the biarch one.  Most people 
> just
>  > get lucky, because they compile code with a compiler that is 
> defaulted
>  > for their target, and userland and kernel use (about) the same 
> options
>  > on most targets.  Not so in biarch land (bleeech).
> Note that up until very recently (and just a bit before conflicting
>  opcodes were added), no -mcpu=XXX was required.  For example, I 
> compiled
>  a 44x kernel with a -mcpu=750 toolchain no problems shortly after Paul
>  posted this.  The only exception to this rule I can possibly think of 
> is
>  85xx.  But even that would be the "very recently" thing I mentioned as
>  I know you can use an 82xx-set toolchain to build for 85xx.
> Having said that..

I do the same thing as well and the only issue I have is that 85xx 
doesn't support strings thus the conditional we currently have for 

- kumar

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