[PATCH v9 14/21] ACPI / processor: Make it possible to get CPU hardware ID via GICC

[Catalin Marinas]

On Thu, Mar 05, 2015 at 02:13:58PM +0100, Rafael J. Wysocki wrote:
> On Thu, Mar 5, 2015 at 12:27 PM, Catalin Marinas
> <catalin.marinas at arm.com> wrote:
> > On Thu, Mar 05, 2015 at 04:03:21PM +0800, Hanjun Guo wrote:
> >> On 2015/3/5 6:46, Rafael J. Wysocki wrote:
> >> > IMO, you really need to define phys_cpuid_t in a common place or people will
> >> > forget that it may be 64-bit, because they'll only be looking at their arch.
> >>
> >> Since x86 and ARM64 are using different types for phys_cpuid_t, we need to
> >> introduce something like following if define it in common place:
> >>
> >> in linux/acpi.h,
> >>
> >> #if defined(CONFIG_X86) || defined(CONFIG_IA64)
> >> typedef u32 phys_cpuid_t;
> >> #define PHYS_CPUID_INVALID (phys_cpuid_t)(-1)
> >> #else if defined(CONFIG_ARM64)
> >> typedef u64 phys_cpuid_t;
> >> #define PHYS_CPUID_INVALID INVALID_HWID
> >> #endif
> >>
> >> I think it's awful, did I miss something?
> 
> Well, you can define the type and PHYS_CPUID_INVALID in the arch
> code and then do this in a common header:
> 
> #ifndef PHYS_CPUID_INVALID
> typedef u32 phys_cpuid_t;
> #define PHYS_CPUID_INVALID (phys_cpuid_t)(-1)
> #endif
> 
> That would allow you to avoid the need to duplicate the
> definitions where it is not necessary.

It's fine by me.

-- 
Catalin