Messages in this thread | | | Date | Fri, 26 Apr 2013 17:10:12 +0100 | From | Will Deacon <> | Subject | Re: [PATCH v8 1/2] arm: introduce psci_smp_ops |
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On Fri, Apr 26, 2013 at 04:36:26PM +0100, Stefano Stabellini wrote: > On Thu, 25 Apr 2013, Nicolas Pitre wrote: > > On Thu, 25 Apr 2013, Will Deacon wrote: > > > I disagree. You're explicitly stating that we pass the `cpuid of target CPU, > > > as from MPIDR'. That's simply not true -- the firmware could choose any > > > numbering scheme to identify the CPUs. For KVM and Xen, it *is* the mpidr, > > > which is why psci-smp.c works at all, but that's where the comment belongs, > > > not in this header file. > > > > At some point, the _kernel_ API for interfacing with the firmware's PSCI > > will have to ensure uniformity somehow. The PSCI interface code could > > translate the passed MPIDR into whatever the firmware decided to use for > > identifying CPUs if needed, keeping this issue localized. > > That is what I had in mind when I said to keep the comment in psci.h > before. > We have to draw the line somewhere to expose a uniform internal kernel > API. However it is a bit difficult to do now given that we have only one > user of the API.
I see psci.h as representing the firmware interface, and psci-smp.c or whatever sits on top as exposing the kernel `API'.
> I don't feel to strongly about this, please let me know what is the > final decision and I'll update the code accordingly. I remind you that > the merge window is approaching :-)
I'd still like the comment to be in psci-smp.c, or a header separate from the firmware bits.
Will
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