Re: [PATCH] powerpc/8xx: use SPRN_EIE and SPRN_EID to enable/disable interrupts

[Christophe Leroy <christophe.leroy@c-s.fr>]

Le 18/08/2016 à 18:34, Segher Boessenkool a écrit :
> On Thu, Aug 18, 2016 at 05:56:02PM +0200, Christophe Leroy wrote:
>> The 8xx has two special registers called EID (External Interrupt
>> Disable) and EIE (External Interrupt Enable) for clearing/setting
>> EE in MSR. It avoids the three instructions set mfmsr/ori/mtmsr or
>> mfmsr/rlwinm/mtmsr.
>
> All 8xx?  What other models?  (5xx for example).

At least 823, 860, 866 and 885 have it.

Looks like the 5xx have it too (at least the 565). Does Linux supports 
that one at all ?

8272 and 8323 don't have it.

>
>> +/* Special MSR manipulation registers */
>> +#define SPRN_EIE	80	/* External interrupt enable (EE=1, RI=1) */
>> +#define SPRN_EID	81	/* External interrupt disable (EE=0, RI=1) */
>> +#define SPRN_NRI	81	/* Non Recoverable interrupt (EE=0, RI=0) */
>
> This is wrong (NRI is 82).  Don't write code you cannot test / don't submit
> code you haven't tested?  :-)

Oops. You're right, copy/paste failure.
Was tested on an 885. Unfortunatly SPRN_NRI is not used (yet) :-(

Christophe