On Thu, 2009-09-03 at 10:12 +0530, Arun R Bharadwaj wrote: > > OK, that's a start I guess. Best would be to replace all of pm_idle with > > cpuidle, which is what should have been done from the very start. > > > > If cpuidle cannot fully replace the pm_idle functionality, then it needs > > to fix that. But having two layers of idle functions is just silly. > > > > Looking at patch 2 and 3, you're making the same mistake on power, after > > those patches there are multiple ways of registering idle functions, one > > through some native interface and one through cpuidle, this strikes me > > as undesirable. > > > > If cpuidle is a good idle function manager, then it should be good > > enough to be the sole one, if its not, then why bother with it at all. > > > > Okay, I'm giving this approach a shot now. i.e. trying to make cpuidle > as _the_ sole idle function manager. This would mean doing away with > pm_idle and ppc_md.power_save. And, cpuidle_idle_call() which is the > main idle loop of cpuidle, present in drivers/cpuidle/cpuidle.c will > have to be called from arch specific code of cpu_idle() > > Also this would mean enabling cpuidle for all platforms, even if the > platform doesn't have multiple idle states. So suppose a platform doesnt > have multiple states, it wouldn't want the bloated code of cpuidle > governors, and would want just a simple cpuidle loop.
Do talk to the powerpc maintainers about this. But yes, something like that should be doable. AFAICT the whole governor thing is optional and cpuidle provides a spinning idle loop by default, and platforms can always register a simple alternative when they set up bits -- the only thing to be careful about is not creating a chicken-egg problem where the platform setup runs before cpuidle is able to register a new handler or something. I'd be delighted to see the end of pm_idle on x86. _______________________________________________ Linuxppc-dev mailing list [email protected] https://lists.ozlabs.org/listinfo/linuxppc-dev
