Re: [RFD] Automatic suspend

Matthew Garrett
2009-02-17T14:19:24Z

On Tue, Feb 17, 2009 at 06:14:34AM -0800, Brian Swetland wrote:
> [Matthew Garrett <mjg59@srcf.ucam.org>]
> > https://lists.linux-foundation.org/pipermail/linux-pm/2009-January/019493.html
> > says that they're the same on their current platform.
>
> Well on the Qualcomm MSM72xx SoCs, yeah they're pretty similar -- we can
> reasonably enter power collapse (full shutdown of the ARM11 and
> peripherals) from idle. But this is not (to my knowledge) true of *all*
> SoCs out there. Also, resuming from this state can take 5-30ms
> (depending on how distracted the baseband processor is by what's going
> on on the network).

Mm. Resume from deep idle on x86 is typically in the usec range, but
this is the kind of constraint that pm_qos exposes nicely.

--
Matthew Garrett | mjg59@srcf.ucam.org