Re: [PATCH] ARM: bcm2836: Send event when onlining other cores

From: Stefan Wahren
Date: Mon Aug 14 2017 - 14:41:23 EST


Hi Eric,

> Stefan Wahren <stefan.wahren@xxxxxxxx> hat am 14. August 2017 um 19:11 geschrieben:
>
>
> Hi Florian,
>
> > Florian Fainelli <f.fainelli@xxxxxxxxx> hat am 14. August 2017 um 18:25 geschrieben:
> >
> >
> >
> >
> > On 08/08/2017 04:04 AM, Phil Elwell wrote:
> > > Secondary cores should enter a low-power idle state when waiting to
> > > be started. The "wfe" instruction causes a core to wait until an event
> > > or interrupt arrives before continuing to the next instruction, and
> > > the "sev" instruction sends a wakeup event to the other cores.
> > >
> > > Add an "sev" (and a memory barrier) to bcm2836_boot_secondary, the
> > > function that wakes the waiting cores during booting. This is required
> > > if the secondary cores are sitting in "wfe", and harmless if not.
> >
> > Eric, should I just pick this up for the upcoming ARM SoC pull requests
> > that I am preparing, or do you have more changes aside from the two tags
> > I already merged?
>
> this patch depends on series "ARM: bcm2836: Move SMP startup code to arch/arm".
>
> I didn't had the time to test Phil's patch in all relevant cases. But i could at least prepare a branch with my changes with the acks.

i prepared the branches bcm2835-dt-next-v2 and bcm2835-soc-next.

Stefan