Re: [PATCH v4 20/28] ARM: owl: Implement CPU enable-method for S500

[Arnd Bergmann]

On Thu, Jun 29, 2017 at 5:22 PM, Andreas FÃrber <afaerber@xxxxxxx> wrote:
> Am 29.06.2017 um 17:07 schrieb Arnd Bergmann:
>>
>> It seems you missed my question here. Can you please follow up, and
>> if possible send a patch to remove the pen_release logic that appears
>> to be unnecessary here?
>
> I do not have any documentation on these registers, only the downstream
> code that I forward-ported here. If you tell me what you mean exactly, I
> can do some testing and if it still works submit a patch to simplify it.
>
> Comments from the so far quiet Actions Semi side would help, too.

IIRC, there are two ways to implement SMP bootup: either you have
registers to tell the secondary CPU how to start up out of reset or they
get put into a holding pen during early boot where they spin waiting
for a variable to get written.

However, doing both is not necessary. See for example mach-sunxi
for an example without the holding pen. I think you can just delete
half of your file to do the same.

        Arnd