[PATCH v2] powerpc/powernv: Use darn instr for random_seed on p9
Segher Boessenkool
segher at kernel.crashing.org
Tue Aug 1 22:57:36 AEST 2017
On Mon, Jul 31, 2017 at 07:10:15PM +1000, Michael Ellerman wrote:
> And ___PPC_RA() is not quite right. The L field is only 2 bits wide, not
> the 5 that ___PPC_RA() allows.
>
> We don't have a __PPC_L() macro, because L fields vary in size and
> location. So I think you're best of open coding it, eg:
>
> +#define PPC_DARN(t, l) stringify_in_c(.long PPC_INST_DARN | \
> + __PPC_RT(t) | \
> + (((l) & 0x3) << 16))
It would be better if you could do a compile-time error if the L value
is out of range. Hrm, nothing else does such checking either?
Segher
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