[PATCH] powerpc/fsl-booke: Work around erratum A-006958

[Scott Wood]

On 07/15/2013 11:53:54 AM, Scott Wood wrote:
> On 07/15/2013 03:45:36 AM, David Laight wrote:
>> Also, if the high word changes, there is no need to loop.
>> Just return the second value with a low word of zero
>> (the returned count happened while the function was active).
> 
> That would be more complicated than looping.

That said, it's since been confirmed internally that the low word  
should always be zero when this happens, so we could share the Cell  
workaround code -- as long as we do something special in the timebase  
sync code so that we don't get stuck if the timebase happens to be  
frozen with TBL==0.  This would avoid the need for scratch registers  
(other than CR0).

-Scott