Re: [PATCH 01/12] ACPI: introduce CONFIG_ACPI_REDUCED_HARDWARE to enable this ACPI mode

[Hanjun Guo <hanjun.guo@linaro.org>]

On 2013-11-19 21:10, Rafael J. Wysocki wrote:
> On Tuesday, November 19, 2013 03:32:57 PM Hanjun Guo wrote:
>> +CC Robert Moore
>>
>> On 2013-11-18 21:37, Rafael J. Wysocki wrote:
>>> On Monday, November 18, 2013 09:21:30 PM Hanjun Guo wrote:
>> [...]
>>>>>>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>>>>>>> Signed-off-by: Al Stone <al.stone@linaro.org>
>>>>>>>> ---
>>>>>>>>  drivers/acpi/Kconfig            | 8 ++++++++
>>>>>>>>  include/acpi/platform/aclinux.h | 4 ++++
>>>>>>>>  2 files changed, 12 insertions(+)
>>>>>>>>
>>>>>>>> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
>>>>>>>> index 589da05..7bbd3b0 100644
>>>>>>>> --- a/drivers/acpi/Kconfig
>>>>>>>> +++ b/drivers/acpi/Kconfig
>>>>>>>> @@ -354,6 +354,14 @@ config ACPI_BGRT
>>>>>>>>         data from the firmware boot splash. It will appear under
>>>>>>>>         /sys/firmware/acpi/bgrt/ .
>>>>>>>>
>>>>>>>> +config ACPI_REDUCED_HARDWARE
>>>>>>>> +     bool "Hardware-reduced ACPI support"
>>>>>>>> +     depends on !(IA64 || X86)
>>>>>>>
>>>>>>> Why don't you use
>>>>>>>
>>>>>>>         depends on (ARM || ARM64)
>>>>>>>
>>>>>>> here instead?
>>>>>>>
>>>>>>
>>>>>> hardware-reduced is not restricted to ARM platforms, that's why
>>>>>>
>>>>>> I used depends on !(IA64 || X86) here.
>>>>>
>>>>> So what exactly are the other platforms using ACPI in the Linux kernel?
>>>>>
>>>>
>>>> To telling the truth, I didn't see any other platform using ACPI except
>>>> IA64, X86 and ARM/ARM64, I just used depends on !(IA64 || x86) for
>>>> future purpose.
>>>
>>> However, if you used "depends on ARM || ARM64" (the parens are not needed BTW),
>>> the subsequent patches wouldn't need to check CONFIG_ARM/CONFIG_ARM64 in
>>> addition to CONFIG_ACPI_REDUCED_HARDWARE.  That would simplify stuff somewhat.
>>
>> Yes, you are right :)
>> It is ok for me to use "depends on ARM || ARM64", but Robert Moore also
>> suggested that hardware-reduced is not restricted to ARM platforms.
> 
> From the ACPICA's point of view, it isn't.
> 
> In the kernel, however, x86 and ia64 are the only users of ACPI in addition to ARM.

Ok, will update it in next version, thanks for the guidance.

Hanjun