I am using custom mx28 board with 5V only supply. It has powersupply for RTC as below. Board has 32.768 KHz and 24 MHz crystal. I would like to run the RTC on power down via 32 KHz crystal instead of 24 MHz crystal.
At the U-Boot prompt, when I tried setting the HW_RTC_PERSISTENT0 register value to 0x121 (Keeping Clock source as 32 KHz and powering up xtal 32 KHz via setting bits CLOCKSOURCE and XTAL32KHZ_PWRUP) as below:
MX28EVK U-Boot > mm 0x80056060
80056060: 00020100 ? 121
After that, I can see the Clock on 32 KHz and 24 MHz which is good. Now when I power down the board, I still see both Clocks running instead of only 32 KHz for RTC. Can anyone share some comments or concerns?