Andriy Gapon wrote: > on 13/09/2010 20:07 Andriy Gapon said the following: >> I am also going to take a look how Linux and OpenSolaris name the C-states. > > Well, Linux does what you suggested, it uses index of a C-state as its name. > There is one difference from our current code - if a C-state is skipped for > some > reason, then its index is not re-used, but the entry is marked as non-valid. > So, if we skip "C2" for some reason, then "C3" will become "C2". Not so on > Linux. > Also, they print a type/class of a C state using C1, C2, C3 and "--" for > higher/unknown types. > > 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 added some FFHW support for ACPI P-states. You can see that in the cpufreq code or in the speedstep driver. -- Nate _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-acpi To unsubscribe, send any mail to "[email protected]"
