I have a BeagleBone Black (REV C) and I have been running the "demo" starterware program. I have noticed that in the PM demo the "Standby", "DS0" and "DS1" modes seem to work for the most part (DS1 does exit to full power mode but UART state does not recover).
I was under the assumption that when entering any of the low power modes the VDD1 (MPU power supply) is ether shut off or reduced (from its normal 1.325v) and the frequency is reduced in alignment to operating at OPP50. When I measure the supplies when it is in any low power state Standby, DS0 or DS1 I see VDD1 (MPU) is still at 1.325v and VDD2 core is still at 1.1v.
Looking at the code it does call ConfigMinimumOPP() function in demoDvfs.c as part of the suspend procedure but this function just looks at the device version ..probably because of the OPP50 issues with silicon 1.0. But it returns OPP_NONE and does not reconfigure any of the supplies or pll's.
Is this wrong? would you not get better power savings if you reduced or cut supplies and frequency prior to suspend or am I missing something?
