[PATCH v3 05/62] acpi: Don't do traditional BIOS table scan for ARM64

[Jan Beulich]

>>> On 23.11.15 at 12:24, <stefano.stabellini at eu.citrix.com> wrote:
> On Tue, 17 Nov 2015, shannon.zhao at linaro.org wrote:
>> From: Shannon Zhao <shannon.zhao at linaro.org>
>> 
>> With the addition of ARM64 that does not have a traditional BIOS to
>> scan, add a #ifdef option for x86 to do the traditional BIOS scanning
>> for tables.
>> 
>> Signed-off-by: Shannon Zhao <shannon.zhao at linaro.org>
>> ---
>>  xen/drivers/acpi/osl.c | 2 ++
>>  1 file changed, 2 insertions(+)
>> 
>> diff --git a/xen/drivers/acpi/osl.c b/xen/drivers/acpi/osl.c
>> index ce15470..db74a90 100644
>> --- a/xen/drivers/acpi/osl.c
>> +++ b/xen/drivers/acpi/osl.c
>> @@ -78,7 +78,9 @@ acpi_physical_address __init acpi_os_get_root_pointer(void)
>>  	} else {
>>  		acpi_physical_address pa = 0;
>>  
>> +		#ifdef CONFIG_X86
>>  		acpi_find_root_pointer(&pa);
>> +		#endif
>>  		return pa;
>>  	}
> 
> I think it might be best to error out earlier if acpi and !efi_enabled
> on arm and arm64.  If we do that we'll never enter this "else".
> 
> If acpi_find_root_pointer doesn't build on arm, we should move it to an
> x86 specific location, such as xen/arch/x86/efi.

No, definitely not (or if anything, then xen/arch/x86/acpi/). Instead
the function itself should be stubbed out to do nothing on ARM. (And
of course also the #ifdef placement is rather odd).

Jan