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Re: powerpc -mcpu=common equivalent ?


On Thu, Feb 9, 2017 at 10:00 AM, Daniel Walker <danielwa@cisco.com> wrote:
>
> Hi,
>
>
> It looks like -mcpu=common (on the powerpc architecture) was removed. My
> group is struggling to find a way to compile generic binaries for PowerPC.
> We have been getting an LWSYNC instruction included in the binaries, and
> some of our processors are getting a trap when this instructions is
> executed. The platforms we are using are all Freescale, they are p2020,
> t1042, and 8540.
>
> Freescale support informed us that we should use -mcpu=common , which is
> gone, we tried a number of other -mcpu setting including -mcpu=powerpc, but
> none of them allow us to have generic binaries for all the platforms.
>
> I suppose this is either a bug report that we're getting lwsync when we
> shouldn't be getting it, or just a question of what the typical tune is to
> make generic binaries ?

Since you have two majorly different classes of PowerPC here, the
answer is there is no way. Basically you have an e500 (8540) and an
e500mc/e5500 (p2020 t1042).  Note the e500 is not full compatible
standard PowerPC but rather a book-e PowerPC. book-e PowerPC are funny
and not fully compatible to the standard PowerPC spec; an example is
lwsync; another example is the floating point unit (e500 has SPE while
the e500mc is the standard PowerPC fp unit).

Thanks,
Andrew

>
> Thanks for any help,
>
> Daniel
>


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