On 2014-8-20 22:56, Catalin Marinas wrote:
> On Tue, Aug 19, 2014 at 09:37:34AM +0100, Hanjun Guo wrote:
>> On 2014-8-18 22:27, Catalin Marinas wrote:
>>> On Mon, Aug 04, 2014 at 04:28:16PM +0100, Hanjun Guo wrote:
>>>> diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
>>>> index e32321c..4007313 100644
>>>> --- a/drivers/acpi/processor_core.c
>>>> +++ b/drivers/acpi/processor_core.c
>>>> @@ -64,6 +64,38 @@ static int map_lsapic_id(struct acpi_subtable_header 
>>>> *entry,
>>>>    return 0;
>>>>  }
>>>>  
>>>> +/*
>>>> + * On ARM platform, MPIDR value is the hardware ID as apic ID
>>>> + * on Intel platforms
>>>> + */
>>>> +static int map_gicc_mpidr(struct acpi_subtable_header *entry,
>>>> +          int device_declaration, u32 acpi_id, int *mpidr)
>>>> +{
>>>> +  struct acpi_madt_generic_interrupt *gicc =
>>>> +      container_of(entry, struct acpi_madt_generic_interrupt, header);
>>>> +
>>>> +  if (!(gicc->flags & ACPI_MADT_ENABLED))
>>>> +          return -ENODEV;
>>>> +
>>>> +  /* In the GIC interrupt model, logical processors are
>>>> +   * required to have a Processor Device object in the DSDT,
>>>> +   * so we should check device_declaration here
>>>> +   */
>>>> +  if (device_declaration && (gicc->uid == acpi_id)) {
>>>> +          /*
>>>> +           * Only bits [0:7] Aff0, bits [8:15] Aff1, bits [16:23] Aff2
>>>> +           * and bits [32:39] Aff3 are meaningful, so pack the Affx
>>>> +           * fields into a single 32 bit identifier to accommodate the
>>>> +           * acpi processor drivers.
>>>> +           */
>>>> +          *mpidr = ((gicc->arm_mpidr & 0xff00000000) >> 8)
>>>> +                   | gicc->arm_mpidr;
>>>
>>> You can use pack_mpidr_into_32_bits().
>>
>> processor_core.c will be used by x86 and ia64 too, it will cause
>> compile error on !ARM64 platforms.
> 
> Oh. So we do we have an ARM-specific function in core ACPI code?

Yes, GICC is ARM-specific, but all the mapping functions (get apic_id/mpidr
via acpi_id in MADT) including x86/ia64 are all there, so it's better to put it
here to keep consistency.

Thanks
Hanjun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to