Re: [update][PATCH v10 06/21] ACPI / sleep: Introduce CONFIG_ACPI_GENERIC_SLEEP

From: Rafael J. Wysocki
Date: Mon Mar 16 2015 - 22:59:27 EST


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 2015å03æ14æ 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?

Perhaps we can use ACPI_REDUCED_HARDWARE_ONLY for that? ARM64 will be the
only arch setting it at least for the time being, is that correct?


--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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