Re: [PATCH 0/1] OMAP3 PM Add C0 state

["Peter 'p2' De Schrijver" <peter.de-schrijver@nokia.com>]

On Mon, Feb 23, 2009 at 07:24:24PM +0100, ext Kevin Hilman wrote:
> "Peter 'p2' De Schrijver" <peter.de-schrijver@nokia.com> writes:
> 
> > This patch introduces a new C state C0 which keeps both core and mpu
> > powerdomains in ON state. This gives us low latency at a cost of higher
> > power consumption.
> >
> 
> I don't like the name 'C0' for an idle-state.  In ACPI terms, C0 is an
> active state, not an idle state.  I know this is not an ACPI system,
> but since we're using ACPI names, we should be consistent.
> 
> Is there a real benefit to having an additional state here?  Shouldn't
> we just make these changes or C1?
> 

C1 has a too high wakeup latency (10s of us) for some cases, but C0 (which has
a 3us wakeup latency) keeps core on which implies little powersavings. So
I think we need both.

Cheers,

Peter.

-- 
goa is a state of mind