Hey, On Mon, Dec 14, 2009 at 05:02:00AM -0500, Youquan,Song wrote: > > > That's true, if CPU has more 3 states such as C3, C6, C7, there are > > > all mapped to ACPI C3. But the current situation is that if platform > > > does NOT support ACPI C2, the user interface /sys show us ACPI C2 is > > > supported which actual is ACPI C3. > > > > > > As you know, ACPI C3 and ACPI C2 have much different, such as: BUS SNOOP > > > or not, ACPI C3 has better power saving etc. we should not mix them. > > > > Yes, but what happens if there are two states of type C2? The whole concept > > of "type C<number>" and "state C<number>" was broken from the beginning... > > Sorry. In my mind, there is no two states of ACPI C2. If processor C3 > above are mapped to ACPI C3, so processor C1 is mapped to ACPI C1, > processor C2 is mapped to ACPI C2. Well, there may be none now, but the ACPI spec 4.0 provides for it in section 8.1.5... The whole mapping of ACPI C-state Types to C-state numbers _is_ confusing. Best, Dominik -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
