On Fri, Feb 4, 2011 at 3:02 PM, Michael Williamson <[email protected]> wrote: > On 2/4/2011 12:15 PM, Steve Chen wrote: > >> On Fri, Feb 4, 2011 at 10:52 AM, Nori, Sekhar <[email protected]> wrote: >>> Hi Steve, >>> >>> On Fri, Feb 04, 2011 at 21:42:41, Steve Chen wrote: >>> >>>>> rtcwake -s 40 rtc0 >>>> rtcwake: /dev/rtc not enabled for wakeup events >>> >>> I have a feeling rtcwake is looking at the wrong device >>> node. Can you try: >>> >>> $ rtcwake -d /dev/rtc0 -s 20 -m mem >>> >> >> Doh!!. Sekhar, you are right. I did not include the "-d" flag. >> After passing the correct parameter to rtcwake, I'm able to wake up >> from sleep with NFS rootfs. I'm running the kernel/filesystem from >> PSP 03.20.00.14. >> > > > I was wondering if you (or anyone) have numbers for how much power the > AM1808 you have is drawing while sleeping? I was able to run the same > command as above with an AM1808 module here today, and the power draw > I am seeing by the module was still pretty high. About 1/2 normal > operation, but still pretty high. > > Does sleeping to disk / MMC reduce the consumption? Or are there other > tricks with the regulators (e.g., allowing them to actually be shut down > with the constraints flags) that need to be done? > > Thanks for any clues.
Mike, I have the Logic PD AM1808 EVM (I'm not sure if there are any others out there). Looking at the SOM-M1 schematic, power to AM1808 and DRAM can be measured at u14 and u16 (pin 1 and 2). With SoC frequency at 300MHz, it uses about 315mW (please note that I turned off audio, video, SATA, and a few other controllers). At suspend, AM1808 + DRAM draws 27 mW. I have not done anything other then the "echo mem..". Also, if I measure the power on R84, I get roughly 45% power saving. Regards, Steve _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
