CPU C-state storange on Panasonic TOUGH BOOK CF-R9

[Taku YAMAMOTO]

On Tue, 14 Sep 2010 11:44:45 +0300
Andriy Gapon <avg at freebsd.org> wrote:

> Additionally, it seems that we do not currently have any support for Functional
> Fixed Hardware (FFH) way of providing C states.  In this case _CST returns GAS
> of a register used to enter a C state with address space ID set to
> ACPI_ADR_SPACE_FIXED_HARDWARE (0x7f/127).  Such addresses should be handled in a
> special way:
> ftp://download.intel.com/technology/IAPC/acpi/downloads/30222305.pdf
> 
> Currently we simply (and silently) ignore such _CST entries.
> I think that this should be useful (if not necessary) with mwait.

I have a proof-of-concept, quick'n'dirty patch against pre-r212541
to utilize FFH _CST.

Unfortunately I have no time to catch up the latest and fantastic work by mav,
though.

-- 
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 | __ <     <taku at tackymt.homeip.net>

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