On Mon, Jun 4, 2012 at 11:02 AM, Martin Peres <martin.peres@xxxxxxx> wrote: > Le 04/06/2012 16:31, Jerome Glisse a écrit : > >> >> I don't think sysfs is the way to go, i am pretty sure that power >> management will change drasticly again in the future especialy btw >> discret and integrated GPU. I would rather have hardware specific >> ioctl. >> >> Cheers, >> Jerome > > Any particular idea of what may change? > > The proposed interface would work even on entirely dynamic > reclocking (per-domain frequency scaling) as opposed to > perflvl-based reclocking. It is unlikely to happen though. > > A more realistic possibility could be that engines would be reclocked > independently according to their internal load. > If that was to happen, then the already-existing API could be used as > a master control and engines could specify the performance level policy > they want (follow master, always min, always max, conservative, dynamic). > > I'm pretty sure voltage domains will soon appear but I don't see what could > possibly be changed that wouldn't be covered by what I proposed. > > As for the reason we would like to use IOCTLs instead of sysfs, I really > don't understand what is the rationale. I personally want to empower the > users to let them decide what is best for them. Sysfs is way easier to > work with! > > Although my idea may be sketchy, I am dead-serious about coming up with > a good API. > > Martin My experience is that things that are true today for GPU, are not tomorrow. Yes there will still be clock/voltage, but there could be new complete different things, like shutting down block. I am not even mentioning things like complex value range dependency btw things (for instance if a domain as clock/voltage in certain range than some other domain can only have clock in a restricted range value). While i agree that sysfs looks easy for user to play with, i believe that gui is what you really after and afaik closed source driver all expose a gui for their power management. Using ioctl allow better overall control, like atomic setting of several domain ... Cheers, Jerome _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
