> This Thinkpad T23 with latest (Oct2006) BIOS & EC shows no FADT .. but > FACP has CST_CNT=0xf4. Is that relevant at all?
An oddity of ACPI -- the FADT has the signature "FACP". > -----Original Message----- > From: owner-freebsd-a...@freebsd.org [mailto:owner-freebsd- > a...@freebsd.org] On Behalf Of Ian Smith > Sent: Monday, July 09, 2012 9:06 AM > To: Nate Lawson > Cc: freebsd-acpi@freebsd.org; Andriy Gapon > Subject: Re: disabled CST_CNT write > > On Sun, 8 Jul 2012 09:49:57 -0700, Nate Lawson wrote: > > On Jul 8, 2012, at 2:11 AM, Andriy Gapon 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? > > This Thinkpad T23 with latest (Oct2006) BIOS & EC shows no FADT .. but > FACP has CST_CNT=0xf4. Is that relevant at all? > > > It was only under an #ifdef because at the time our CST > > implementation couldn't handle CST changes cleanly. I had added some > > support for it, but since it couldn't be tested, I wasn't sure how > > actual hardware would behave. > > > > I think it's fine to enable now. I think 2007-era Thinkpads were > some > of the first to add this feature. > > T43? Maybe it's time I upgraded :) > > cheers, Ian > _______________________________________________ > freebsd-acpi@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-acpi > To unsubscribe, send any mail to "freebsd-acpi-unsubscr...@freebsd.org" _______________________________________________ freebsd-acpi@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-acpi To unsubscribe, send any mail to "freebsd-acpi-unsubscr...@freebsd.org"
