On 2014-8-20 22:52, Catalin Marinas wrote: > On Tue, Aug 19, 2014 at 09:32:25AM +0100, Hanjun Guo wrote: >> On 2014-8-18 22:27, Catalin Marinas wrote: >>> On Mon, Aug 04, 2014 at 04:28:15PM +0100, Hanjun Guo wrote: >>>> +#ifdef CONFIG_ACPI >>>> +/* >>>> + * Get a cpu's boot method in the ACPI way. >>>> + */ >>>> +static char * __init acpi_get_cpu_boot_method(void) >>>> +{ >>>> + /* >>>> + * For ACPI 5.1, only two kind of methods are provided, >>>> + * Parking protocol and PSCI, but Parking protocol is >>>> + * specified for ARMv7 only, so make PSCI as the only method >>>> + * for SMP initialization before the ACPI spec or Parking >>>> + * protocol spec is updated. >>>> + */ >>>> + switch (smp_boot_protocol()) { >>>> + case ACPI_SMP_BOOT_PSCI: >>>> + return "psci"; >>>> + case ACPI_SMP_BOOT_PARKING_PROTOCOL: >>>> + default: >>>> + return NULL; >>>> + } >>>> +} >>> >>> Actually, do we even need to define smp_boot_protocol()? Is it used >>> anywhere else apart from this patch (I still haven't gone through all >>> patches)? >> >> It is just used in this patch. I think we can make the ACPI boot protocol >> scalable in this way, if we support another boot protocol in ACPI in the >> future, we can easily update the function to support it, does it make sense? > > Not really. You just add additional code, enums, functions when all you > do is check for acpi_psci_present() (or whatever new protocol you would > get). If the enum is never going to be used outside this file, don't > bother with additional functions. > > BTW, it would be nicer if the acpi related functions are contained in as > fewer files as possible. So here you could keep > acpi_get_cpu_boot_method() in the acpi.c file. It only returns a string. ok, I will update them. Thanks Hanjun -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html