Re: [PATCH RFC 2/2] soc: Add a basic ACPI generic driver

[Rafael J. Wysocki]

On Tue, Jan 28, 2020 at 8:28 PM John Garry <john.garry@xxxxxxxxxx> wrote:
>
>
> >>>>
> >>>> Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
> >>>> ---
> >>>>    drivers/soc/Makefile       |   1 +
> >>>>    drivers/soc/acpi_generic.c | 102 +++++++++++++++++++++++++++++++++++++
> >>>>    2 files changed, 103 insertions(+)
> >>>>    create mode 100644 drivers/soc/acpi_generic.c
> >>>>
> >>>> diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
> >>>> index 8b49d782a1ab..2a59a30a22cd 100644
> >>>> --- a/drivers/soc/Makefile
> >>>> +++ b/drivers/soc/Makefile
> >>>> @@ -3,6 +3,7 @@
> >>>>    # Makefile for the Linux Kernel SOC specific device drivers.
> >>>>    #
> >>>>
> >>>> +obj-$(CONFIG_ACPI_PPTT)                += acpi_generic.o
> >>>>    obj-$(CONFIG_ARCH_ACTIONS)     += actions/
> >>>>    obj-$(CONFIG_SOC_ASPEED)       += aspeed/
> >>>>    obj-$(CONFIG_ARCH_AT91)                += atmel/
> >>>
> >>> Based on everything I've seen so far, this should go under drivers/acpi instead.
> >>
> >> soc drivers seem to live in drivers/soc (non-arm32, anyway), so I
> >> decided on this location. But drivers/acpi would also seem reasonable now.
> >
>
> Hi Rafael,
>
> > Any reasons for not putting it into drivers/acpi/pptt.c specifically?
> > .
>
> I don't think so.
>
> One thing is that the code does a one-time scan of the PPTT to find all
> processor package nodes with ID structures to register the soc devices -
> so we would need some new call from from acpi_init() for that.

Or an extra initcall or similar. [Calls from acpi_init() are basically
for things that need to be strictly ordered in a specific way for some
reason.]

Why would that be a problem?