> how can we get this tool.so we can exactly know which C and P states the > system using. > then, > how can we set the CPU into Deeper sleep。like pxa270，we can change cpu > mode by writting cp15 register > > we check the datasheet of both z5xx and SCH(us15wx) ,but find no > description of how can we generate the signals which can force CPU enter > Deeper sleep. Why not google :) http://www.lesswatts.org/projects/powertop/
Again, like arjan said, when you are trying to 'setting' it, that means your cpu is working, so at this kind of situation, you CAN NOT enter into deep c because cpu is working to your task. Please let OS/CPU decide when and which level it should go to rather than 'setting' it. > my purpose is to check the cpu Actual power loss when cpu work in Deeper > sleep(C4)（or Deep power down(C6)）. Maybe you should use some physical device like power meter rather than by 'setting something and check it' for this purpose. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of 刘应杰 Sent: Wednesday, September 16, 2009 2:20 PM To: Arjan van de Ven Cc: dev Subject: Re: [Moblin Dev] low power state of atom Hi： thanks for your answer。 first， “I suspect that your system WILL go into C4. If you are not sure, you can run the powertop tool,”how can we get this tool.so we can exactly know which C and P states the system using. then, how can we set the CPU into Deeper sleep。like pxa270，we can change cpu mode by writting cp15 register we check the datasheet of both z5xx and SCH(us15wx) ,but find no description of how can we generate the signals which can force CPU enter Deeper sleep. 在2009-09-16?13:43:30，"Arjan?van?de?Ven"?<[email protected]>?写道： >刘应杰?wrote: >>?Hi?zhang: >>?? >>?????my?purpose?is?to?check?the?cpu?Actual?power?loss?when?cpu?work?in?Deeper?sleep(C4)（or?Deep?power?down(C6)）.? >>?????as?you?say:"Which?cstate?will?be?entered?is?the?responsibility?of?cpu?idle?state?driver?of?OS,"?So?which?driver?of?moblin?work?on?this?function,and?how?can?we?change?the?cstate?in?usrspace?of?linux,the?driver?should?have?interface?which?we?can?use?in?my?applications. >>?? >>?????looking?forward?your?answer > >you?fundamentally?CANNOT?change?that?state?from?userspace...?because?when?you?are?executing?in?userspace,?your?computer?is?not?idle?and?thus? >cannot?be?in?an?idle?(C)?state... _______________________________________________ Moblin dev Mailing List [email protected] To manage or unsubscribe from this mailing list visit: http://lists.moblin.org/listinfo/dev or your user account on http://moblin.org once logged in. For more information on the Moblin Developer Mailing lists visit: http://moblin.org/community/mailing-lists _______________________________________________ Moblin dev Mailing List [email protected] To manage or unsubscribe from this mailing list visit: http://lists.moblin.org/listinfo/dev or your user account on http://moblin.org once logged in. For more information on the Moblin Developer Mailing lists visit: http://moblin.org/community/mailing-lists
