Dean
Thu Jul 19 08:36:28 CDT 2007
The same as it was before. The kernel constantly transitions in and out of
Idle (meaning OEMIdle) whenever a thread blocks and nothing else is
scheduled to run. This happens at the millisecond level and is transparent
to the Power Manager, which works with system wide events on a much larger
time scale.
Maybe the key to understanding this is to recognize that the kernel Idle
refers to idling the processor at the thread level (microscopic) and the PM
refers to system level events (macroscopic). The two execute in parallel,
and the PM has no idea if the kernel has placed the processor in a low power
mode via OEMIdle.
--
Dean Ramsier - eMVP
BSQUARE Corporation
"Stanley" <Stanley@discussions.microsoft.com> wrote in message
news:D9EF19D7-A564-48D8-9746-A813F348FBB4@microsoft.com...
> Imaging a senario that if the kernel power state goes into idle, what is
> the
> system power state of PDA sample right now? I don't know the relation
> between
> them.
>
> Thank you,
>
> "Dean Ramsier" wrote:
>
>> Yes they are independent, although there is some interaction between the
>> two. The low level "kernel" power management refers to the device
>> support
>> for OEMIdle and the suspend/resume sequence. OEMIdle is totally
>> transparent
>> to applications and drivers. It allows the CPU to go into a low power
>> mode
>> if no threads are currently running and immediately go back to a higher
>> power mode when an interrupt occurs. This requires support from both the
>> cpu and the OAL (OEM portion of the kernel).
>>
>> The suspend/resume sequence is controlled by the kernel and occurs
>> *after*
>> the higher level Power Manager code triggers the sequence to begin. This
>> can happen due to a system timeout event or an application call to
>> SetSystemPowerState().
>> --
>> Dean Ramsier - eMVP
>> BSQUARE Corporation
>>
>>
>> "Stanley" <Stanley@discussions.microsoft.com> wrote in message
>> news:31C14CE6-6052-4FD5-A145-645A152409B5@microsoft.com...
>> > Excuse me, I don't understand exactly.
>> > Do you means that they are independent? Are there not conflict between
>> > them, if they are controlled separately?
>> > If OK, the system power state transition is controlled by whom. And,
>> > What
>> > are the trigger events?
>> >
>> > "Dean Ramsier" wrote:
>> >
>> >> Neither. This is separate (lower level) power management that is
>> >> controlled
>> >> by the kernel/hardware. It runs simultaneously with the functionality
>> >> provided by the Power Manager (PM.dll) component. The PM
>> >> functionality
>> >> occurs only during the block labeled On, but it can trigger events
>> >> that
>> >> cause transitions out of this block.
>> >>
>> >> --
>> >> Dean Ramsier - eMVP
>> >> BSQUARE Corporation
>> >>
>> >>
>> >> "Stanley" <Stanley@discussions.microsoft.com> wrote in message
>> >> news:D6324928-88A6-476A-BA20-2511454FA208@microsoft.com...
>> >> > Thanks for your kindly help.
>> >> > And, there is another question about the power state and
>> >> > transitions.
>> >> > The trasition between the power state which is described in
>> >> > "
http://msdn2.microsoft.com/en-us/library/aa450568.aspx" is the
>> >> > default
>> >> > model
>> >> > or PDA model? It is difficult to know what is the "real" system
>> >> > power
>> >> > state
>> >> > which I use and what is the condition of transition.
>> >> >
>> >> > Best wishes,
>> >> >
>> >> > "Bruce Eitman [eMVP]" wrote:
>> >> >
>> >> >> This points out why it is important to mention the version that you
>> >> >> are
>> >> >> using.
>> >> >>
>> >> >> So look for the PXA270 display driver in Public\Common\Oak\CSP for
>> >> >> CE
>> >> >> 5.0
>> >> >>
>> >> >> --
>> >> >> Bruce Eitman (eMVP)
>> >> >> Senior Engineer
>> >> >> beitman AT applieddata DOT net
>> >> >>
>> >> >> Applied Data Systems
>> >> >> www.applieddata.net
>> >> >> An ISO 9001:2000 Registered Company
>> >> >> Microsoft WEP Gold-level Member
>> >> >>
>> >> >> "Stanley" <Stanley@discussions.microsoft.com> wrote in message
>> >> >> news:FDEEB3DF-F084-45C6-947E-A3B60B23FF00@microsoft.com...
>> >> >> > Excuse me, would you please tell me what the version of PB is?
>> >> >> > I can't find the path in PB 5.0 .
>> >> >> > Thank you,
>> >> >> >
>> >> >> >
>> >> >> > "Bruce Eitman [eMVP]" wrote:
>> >> >> >
>> >> >> >> Search for "power" in the PXA270 display driver.
>> >> >> >> (PLATFORM\COMMON\SRC\SOC\PXA27X_MS_V1\DISPLAY\PXA27X_LCD)
>> >> >> >>
>> >> >> >> --
>> >> >> >> Bruce Eitman (eMVP)
>> >> >> >> Senior Engineer
>> >> >> >> beitman AT applieddata DOT net
>> >> >> >>
>> >> >> >> Applied Data Systems
>> >> >> >> www.applieddata.net
>> >> >> >> An ISO 9001:2000 Registered Company
>> >> >> >> Microsoft WEP Gold-level Member
>> >> >> >>
>> >> >> >> "Stanley" <Stanley@discussions.microsoft.com> wrote in message
>> >> >> >> news:0C58F206-1E57-4410-B943-F7F96C092114@microsoft.com...
>> >> >> >> > Thanks for your response.
>> >> >> >> > Further, the driver must implement the IO control function for
>> >> >> >> > handing
>> >> >> >> > the
>> >> >> >> > power state changing. Is it the same for the GWES driver? Is
>> >> >> >> > there
>> >> >> >> > any
>> >> >> >> > sample
>> >> >> >> > of power manager for display driver ?
>> >> >> >> >
>> >> >> >> > Thanks a lot
>> >> >> >> >
>> >> >> >> > "Dean Ramsier" wrote:
>> >> >> >> >
>> >> >> >> >> The components are selected in
>> >> >> >> >> WINCE600\PUBLIC\CEBASE\OAK\MISC\winceos.bat
>> >> >> >> >> based on sysgen variables. In that file, you can see that
>> >> >> >> >> the
>> >> >> >> >> PM
>> >> >> >> >> PDA
>> >> >> >> >> component adds support for pda version, otherwise the default
>> >> >> >> >> version
>> >> >> >> >> is
>> >> >> >> >> used. So if you have PDA is selected, that should be the one
>> >> >> >> >> you
>> >> >> >> >> get.
>> >> >> >> >>
>> >> >> >> >> You can modify the mappings by adding entries for them in
>> >> >> >> >> platform.reg.
>> >> >> >> >> Platform.reg overrides common.reg.
>> >> >> >> >>
>> >> >> >> >> --
>> >> >> >> >> Dean Ramsier - eMVP
>> >> >> >> >> BSQUARE Corporation
>> >> >> >> >>
>> >> >> >> >>
>> >> >> >> >> "Stanley" <Stanley@discussions.microsoft.com> wrote in
>> >> >> >> >> message
>> >> >> >> >> news:1685435C-22D4-4DFB-A6E3-AAB1481F5B8B@microsoft.com...
>> >> >> >> >> >I have some questions.
>> >> >> >> >> > How do I know what kind of system power which I use, If I
>> >> >> >> >> > add
>> >> >> >> >> > two
>> >> >> >> >> > PM
>> >> >> >> >> > models
>> >> >> >> >> > (Default and PDA)?
>> >> >> >> >> > How to modify the mapping of system power state to device
>> >> >> >> >> > power
>> >> >> >> >> > state
>> >> >> >> >> > without
>> >> >> >> >> > modify common.reg?
>> >> >> >> >> >
>> >> >> >> >> > Please give me advise.
>> >> >> >> >> >
>> >> >> >> >> > Best regards
>> >> >> >> >>
>> >> >> >> >>
>> >> >> >> >>
>> >> >> >>
>> >> >> >>
>> >> >> >>
>> >> >>
>> >> >>
>> >> >>
>> >>
>> >>
>> >>
>>
>>
>>