[PATCH V3 0/6] ARM64: Add support for FSL's LS2085A SoC

[mark.rutland@arm.com (Mark Rutland)]

On Sat, Sep 20, 2014 at 09:35:08PM +0100, bhupesh.sharma at freescale.com wrote:
> Ping?

Hi Bhupesh,

> > -----Original Message-----
> > From: Sharma Bhupesh-B45370
> > Sent: Tuesday, September 09, 2014 5:16 PM
> > To: 'Arnd Bergmann'; Mark Rutland
> > Cc: linux-arm-kernel at lists.infradead.org; rob.herring at linaro.org; Catalin
> > Marinas; Will Deacon; Yoder Stuart-B08248; grant.likely at secretlab.ca;
> > Marc Zyngier; Basu Arnab-B45036; Geoff Levand
> > Subject: RE: [PATCH V3 0/6] ARM64: Add support for FSL's LS2085A SoC
> > 
> > Hi Mark, Arnd
> > 
> > > -----Original Message-----
> > > From: Arnd Bergmann [mailto:arnd at arndb.de]
> > > Sent: Thursday, September 04, 2014 3:09 PM
> > > To: Mark Rutland
> > > Cc: linux-arm-kernel at lists.infradead.org; rob.herring at linaro.org;
> > > Sharma Bhupesh-B45370; Catalin Marinas; Will Deacon; Yoder
> > > Stuart-B08248; grant.likely at secretlab.ca; Marc Zyngier; Basu
> > > Arnab-B45036; Geoff Levand
> > > Subject: Re: [PATCH V3 0/6] ARM64: Add support for FSL's LS2085A SoC
> > >
> > > On Thursday 04 September 2014 10:13:19 Mark Rutland wrote:
> > > > On Wed, Sep 03, 2014 at 07:31:44PM +0100, Arnd Bergmann wrote:
> > > > > On Wednesday 03 September 2014 17:31:30 Mark Rutland wrote:
> > > > > >
> > > > > > However, I'm not sure I follow the reasoning for making this
> > > > > > significantly harder, and even ignoring that I don't think this
> > > > > > does make things significantly harder. Especially so if we have
> > > > > > a PSCI node but not an enable method -- in that case its trivial
> > > > > > to patch in an unrelated enable-method anyhow.
> > > > >
> > > > > Right, it's not actually much harder. A better way to look at it
> > > > > is probably that we document what which parts we expect to stay
> > > > > constant and which parts are to be filled out by the boot loader.
> > > > > Independent of what PSCI implementation the boot loader provides,
> > > > > we would like to see enable-method="psci".
> > > >
> > > > So in the /cpus node, have a comment like:
> > > >
> > > > /*
> > > >  * We expect the enable-method to be "psci", but this is dependent
> > > > on
> > > >  * the FW, which will fill this in.
> > > >  */
> > >
> > > I was thinking of leaving the enable-method in the cpus node, but
> > > having an empty psci node with a similar comment.
> > >
> > > > Or, should we put together a soc-guidance.txt with that, ensuring
> > > > things are initialised correctly (CNTVOFF, CNTFREQ), etc?
> > >
> > > I would very much welcome documentation like that!
> > 
> > Is this documentation planned (already being worked upon), or should I
> > try to spin-out a RFC patch which tries to add this guidance
> > documentation.

If you'd be willing to put together an RFC, that would be welcomed. It
has so far been a TODO item that no-one has had the time for.

Mark.