On Tue, Jul 12, 2016 at 2:59 PM, Sudeep Holla [off-list ref] wrote:

On 12/07/16 13:09, Rafael J. Wysocki wrote:

quoted

On Tuesday, July 12, 2016 12:42:06 PM Sudeep Holla wrote:

quoted

On 08/07/16 18:07, Sudeep Holla wrote:

quoted

ACPI 6.0 introduced LPI(Low Power Idle) states that provides an
alternate
method to describe processor idle states. It extends the specification
to allow the expression of idle states like C-states selectable by the
OSPM when a processor goes idle, but may affect more than one processor,
and may affect other system components.

LPI extensions leverages the processor container device(again introduced
in ACPI 6.0) allowing to express which parts of the system are affected
by a given LPI state. It defines the local power states for each node
in a hierarchical processor topology. The OSPM can use _LPI object to
select a local power state for each level of processor hierarchy in the
system. They used to produce a composite power state request that is
presented to the platform by the OSPM.

Since multiple processors affect the idle state for any non-leaf
hierarchy
node, coordination of idle state requests between the processors is
required. ACPI supports two different coordination schemes: Platform
coordinated and  OS initiated.

I was hoping to get this in v4.8 now that merge window is
delayed/extended if you have no further comments on this series.

I'll get to it in the next couple of days.  If it looks all good and there
are
no comments, I'll queue it up.

Thanks for the update.

I've just looked at patch [2/7] and there still are things I'm not
particularly liking in it.

Apart from a bunch of minor stuff, acpi_processor_get_lpi_info() is
not my favorite.  The way it creates all of those temporary data
structures and then walks them recursively seems a bit excessive.

I need to think about it a bit more, so I'll send my comments on that
patch later this week.

Thanks,
Rafael