On 08/23/2013 02:54 AM, Scott Wood wrote: > On Thu, 2013-08-22 at 11:20 +0530, Deepthi Dharwar wrote: >> On 08/22/2013 01:38 AM, Scott Wood wrote: >>> On Wed, 2013-08-21 at 10:23 +0530, Deepthi Dharwar wrote: >>>> On 08/19/2013 11:47 PM, Scott Wood wrote: >>>>> What actual functionality is common to all powerpc but not common to >>>>> other arches? >>> >> >> The functionality here is idle states on powerpc like the snooze loop >> that is common. >> Also, the basic registration of the driver, hotplug notifier etc for >> powerpc. > > The snooze loop uses things like SPRN_PURR, get_lppaca(), and CTRL which > aren't common to all PPC (they might be common to all book3s64). I also > don't see any hook for the low power mode entry -- is "snooze" just a > busy loop plus the de-emphasis stuff like HMT and CTRL[RUN]? I'm not > familiar with the term "snooze" in this context. I don't think we'd use > anything like that on our chips; we'd always at least "wait" or "doze" > depending on the chip. > Duly noted. Lot of stuff are common across book3s64. So my later versions of this patchset does just that. (V5 posted out yesterday). The driver is common only to IBM-POWER platform. Other PPC variants can have their own driver. > It's not clear what is powerpc-specific about the notifier -- perhaps it > should go in drivers/cpuidle/. Currently all the arcs have their own hotplug notifier. Unifying this across all archs is a challenge that needs to be taken going forward. Thanks for the review. Regards, Deepthi >>> The way forward is to give this file a more appropriate name based on >>> the hardware that it actually targets -- and to refactor it so that the >>> answer to that question is not complicated. >> >> Sure, thanks. >> Our idea was to have POWER archs idle states merged at the first go. >> Only that is what is enabled in the current version (V4 posted out) >> ( Code is enabled for PSERIES and POWERNV only) >> If needed, other POWERPC archs might benefit by extending the same >> driver, that is why it is named cpuidle-powerpc.c >> >> But if having cpuidle backend-driver separately for other powerpc arcs >> makes sense such that each one have their own state information etc >> then it makes sense to name the files as cpuidle-power.c, >> cpuilde-ppc32.c and so on. > > Thanks. > > -Scott > > > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@xxxxxxxxxxxxxxxx > https://lists.ozlabs.org/listinfo/linuxppc-dev > >
