Re: [PATCH v6 4/5] arm64: add support for ACPI Low Power Idle(LPI)

[Sudeep Holla]

On 27/06/16 18:07, Sudeep Holla wrote:
> On 27/06/16 17:29, Daniel Lezcano wrote:

[...]

> > acpi_disabled - acpi_disabled - acpi_disabled everywhere :/
> >
> > The enable-method approach is not straightforward and now it is polluted
> > by acpi-disabled.
> >
> > So IIUC,
> >
> > smp_init_cpus (contains acpi_disabled)
> >    smp_cpu_setup
> >      cpu_read_ops
> >        cpu_read_enable_method (contains acpi_disabled)
> >          acpi_get_enable_method (returns 'psci' after checking
> > psci_is_present)
> >
> > Then psci_cpu_init_idle is called... and check again acpi_disabled.
> >
> > IMO, the circumlocution with the psci vs acpi vs acpi_disabled is
> > getting unnecessary too complex, is prone to error and will lead to
> > unmaintainable code very soon.
> >
> > I suggest to sort out encapsulation and self-contained code before
> > adding more feature in this area.
>
> I understand your concern but I have no idea on how to clean up. Lorenzo
> asked to factor our common code between psci_{dt,acpi}_cpu_init_idle and
> I think you might not like the refactoring[1]. I didn't want to change
> cpuidle_ops and hence psci_dt_cpu_init_idle parameters. I will see if
> changing that simplifies things.

One of the reasons for adding acpi_disabled check is to keep the other
logic at the same place. Otherwise we end up duplicating that code which
is what I have done in psci_{dt,acpi}_cpu_init_idle at the first place.

--
Regards,
Sudeep