On Sun, 08 Jul 2012 12:11:32 +0300 Andriy Gapon <[email protected]> wrote:
> > acpi_cpu.c has a block of code to write CST_CNT to SMI_CMD, but the block is > under #ifdef notyet. It seems that the code was added that many years ago and > never enabled. > Now, judging from the reports I've seen on this mailing list, it appears that > _CST changes do happen and the driver seem to handle them sufficiently well. > I think that a lot of modern platforms do not even provide CST_CNT and assume > that an OS is able to handle C-state change notifications. > So, I guess that it should be safe to enable the code in question now. > > Could anyone with a FreeBSD laptop and non-zero CST_CNT in FADT please test > this? My Thinkpad X60 (Core 2 Duo) is such one of them. Enabling that code makes this laptop correctly raise _CST change notification on AC status change without a single problem. Without enabling that, this laptop never generates such notifications. In fact, I have been enabling that code locally for more than a couple of years without a problem :) In addition, that does not interfere with jkim's acpi_cx_native2.diff; I've been enjoying MWAIT C3 with varying sleep depth based upon AC availability. -- -|-__ YAMAMOTO, Taku | __ < <[email protected]> - A chicken is an egg's way of producing more eggs. - _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-acpi To unsubscribe, send any mail to "[email protected]"
