[U-Boot] ARM: PSCI 0.1 vs 0.2

[bhupesh.sharma at freescale.com]

Hi, 

> -----Original Message-----
> From: u-boot-bounces at lists.denx.de [mailto:u-boot-bounces at lists.denx.de]
> On Behalf Of Jan Kiszka
> Sent: Monday, November 10, 2014 6:56 PM
> To: Marc Zyngier
> Cc: u-boot at lists.denx.de
> Subject: Re: [U-Boot] ARM: PSCI 0.1 vs 0.2
> 
> On 2014-11-10 14:08, Marc Zyngier wrote:
> > On 10/11/14 12:51, Jan Kiszka wrote:
> >> Hi Marc,
> >>
> >> what is the motivation to expose a PSCI 0.1 interface in U-boot,
> >> instead of 0.2? Support for preexisting users of 0.1? The kernel
> >> seems to be happy with both, and I'm now wondering if we should
> >> actually add the legacy version to Jailhouse as well (I hope we can
> avoid this).
> >
> > The initial rational was simple: at the time this code was written,
> > the
> > 0.2 spec still in review, and nobody was implementing it. Supporting
> > 0.1 was the only viable use-case.
> >
> >> Still studying the logic: Is it possible to provide both interfaces,
> >> and would it make sense?
> >
> > Supporting both is very easy. Just output the 0.2 function numbers
> > that actually make sense for 0.1 and have both compatible strings.
> 
> Ah, cool - parameters and return values of, say, CPU_ON/OFF are
> compatible across both versions?
> 
> Jan
> 
> --

We did send out some ARMv8 PSCI v0.2 u-boot patches, which can be seen here:

http://permalink.gmane.org/gmane.comp.boot-loaders.u-boot/194210

Regards,
Bhupesh