From mboxrd@z Thu Jan  1 00:00:00 1970
From: guohanjun@huawei.com (Hanjun Guo)
Date: Wed, 18 Mar 2015 09:56:43 +0800
Subject: [update][PATCH v10 06/21] ACPI / sleep: Introduce
 CONFIG_ACPI_GENERIC_SLEEP
In-Reply-To: <16235723.xVJ1Rfp9tM@vostro.rjw.lan>
References: <1426234469-6434-1-git-send-email-hanjun.guo@linaro.org>
 <10995588.scpoK3KRg2@vostro.rjw.lan> <5507A91A.1090206@huawei.com>
 <16235723.xVJ1Rfp9tM@vostro.rjw.lan>
Message-ID: <5508DB5B.2060600@huawei.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 2015/3/17 22:33, Rafael J. Wysocki wrote:
> On Tuesday, March 17, 2015 12:10:02 PM Hanjun Guo wrote:
>> On 2015/3/17 11:23, Rafael J. Wysocki wrote:
>>> On Tuesday, March 17, 2015 10:36:47 AM Hanjun Guo wrote:
>>>> On 2015/3/17 10:28, Rafael J. Wysocki wrote:
>>>>> On Tuesday, March 17, 2015 09:08:45 AM Hanjun Guo wrote:
>>>>>> On 2015/3/17 7:15, Rafael J. Wysocki wrote:
>>>>>>> On Monday, March 16, 2015 08:14:52 PM Hanjun Guo wrote:
>>>>>>>> On 2015?03?14? 05:49, Rafael J. Wysocki wrote:
>>>>>>>>> On Friday, March 13, 2015 04:14:29 PM Hanjun Guo wrote:
>>>>>> [...]
>>>>>>>>>> diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
>>>>>>>>>> index 074e52b..e8728d7 100644
>>>>>>>>>> --- a/arch/ia64/Kconfig
>>>>>>>>>> +++ b/arch/ia64/Kconfig
>>>>>>>>>> @@ -10,6 +10,7 @@ config IA64
>>>>>>>>>>   	select ARCH_MIGHT_HAVE_PC_SERIO
>>>>>>>>>>   	select PCI if (!IA64_HP_SIM)
>>>>>>>>>>   	select ACPI if (!IA64_HP_SIM)
>>>>>>>>>> +	select ACPI_GENERIC_SLEEP if ACPI
>>>>>>>>>>   	select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
>>>>>>>>>>   	select HAVE_UNSTABLE_SCHED_CLOCK
>>>>>>>>>>   	select HAVE_IDE
>>>>>>>>>> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
>>>>>>>>>> index b7d31ca..9804431 100644
>>>>>>>>>> --- a/arch/x86/Kconfig
>>>>>>>>>> +++ b/arch/x86/Kconfig
>>>>>>>>>> @@ -22,6 +22,7 @@ config X86_64
>>>>>>>>>>   ### Arch settings
>>>>>>>>>>   config X86
>>>>>>>>>>   	def_bool y
>>>>>>>>>> +	select ACPI_GENERIC_SLEEP if ACPI
>>>>>>>>> One more nit.  If you did
>>>>>>>>>
>>>>>>>>> +	select ACPI_GENERIC_SLEEP if ACPI_SLEEP
>>>>>>>>>
>>>>>>>>> here (and above for ia64), you'd avoid having to make ACPI_SLEEP
>>>>>>>>> depend on ACPI_GENERIC_SLEEP which goes somewhat backwards.
>>>>>>>> In sleep.c,
>>>>>>>>
>>>>>>>> #ifdef CONFIG_ACPI_SLEEP
>>>>>>>> acpi_target_system_state()
>>>>>>>> {
>>>>>>>> }
>>>>>>>> #endif
>>>>>>>>
>>>>>>>> and CONFIG_ACPI_SLEEP depends on SUSPEND || HIBERNATION,
>>>>>>>> which one of them will be enabled on ARM64 so ACPI_SLEEP
>>>>>>>> will also enabled too.
>>>>>>>>
>>>>>>>> So if we
>>>>>>>>
>>>>>>>> +select ACPI_GENERIC_SLEEP if ACPI_SLEEP
>>>>>>>>
>>>>>>>> and
>>>>>>>>
>>>>>>>> +acpi-$(CONFIG_ACPI_GENERIC_SLEEP) += sleep.o
>>>>>>>>
>>>>>>>> it will lead to errors for acpi_target_system_state() that
>>>>>>>> is declared but not defined, so I will keep the code as
>>>>>>>> it is, what do you think?
>>>>>>> No, we need to hash this out.  Having two different Kconfig options meaning
>>>>>>> almost the same thing (ACPI_SLEEP and ACPI_GENERIC_SLEEP) is beyond ugly.
>>>>>>>
>>>>>>> Do you need ACPI_SLEEP on ARM64 at all?
>>>>>> No, at least for now we don't need it, the spec for sleep is not ready for
>>>>>> ARM64 arch, so ACPI_SLEEP will not work at all on ARM64.
>>>>> Well, so what about selecting ACPI_SLEEP from the architectures that use it?
>>>> Do you mean remove CONFIG_ACPI_GENERIC_SLEEP and
>>>>
>>>> +acpi-$(CONFIG_ACPI_SLEEP) += sleep.o
>>>>
>>>> as well (also need to remove duplicate #ifdef CONFIG_ACPI_SLEEP in sleep.c if
>>>> we doing so)?
>>> Well, almost.  There is one problem with that, becuase sleep.c contains code
>>> outside of the ACPI_SLEEP-dependent blocks.  That code is used for powering
>>> off ACPI platforms.
>>>
>>> I guess you don't want that code on ARM too, right?
>> Yes, you are right.
>>
>>> Perhaps we can use ACPI_REDUCED_HARDWARE_ONLY for that?  ARM64 will be the
>> Sorry, I can't fully understand your intention here, could you please
>> explain it more?
>>
>> Let me guess a little bit. Do you mean use ACPI_REDUCED_HARDWARE_ONLY for
>> powering off ACPI platforms? if so, I guess it's not a good idea, ACPI spec
>> only says that S4BIOS is not supported on HW-reduced ACPI platforms, S5
>> has no such limitation, if I miss something here, please let me know.
> OK, so in your current patch, please replace ACPI_GENERIC_SLEEP with
> ACPI_SYSTEM_POWER_STATES_SUPPORT and all should be clear.

OK, I will send a updated patch.

Thanks
Hanjun