I've noticed a difference in behavior between the latest Angstrom Linux 
image and the latest Debian image available for the BeagleBone Black when 
it comes to enumerating the real-time clocks present when a RTC "Cape" is 
"present". [I have the actual clock present by use of a generic breakout 
board, but not the actual cape.]

I am trying to determine if Angstrom Linux has a patch that is not present 
in Debian, as I prefer the RTC behavior I am seeing in Angstrom. (I'd think 
Debian would want the Angstrom behavior, because if the user has attached 
an RTC, then there is most likely a battery backing it; the BBB currently 
does not support shutdown to the RTC rail only, so the on-board RTC is 
going to be wrong on a cold boot.)

When I tell Angstrom that I have a "BB-BONE-RTC" cape attached, my RTC (the 
DS1307) is enumerated as /dev/rtc0. As such, my clock becomes the clock 
that is used to set the system clock, and is otherwise going to get all of 
the privileges of being the first RTC.

When I tell Debian that I have a "BBB-RTC-01" cape attached, the on-board 
RTC is still enumerated as /dev/rtc0. My RTC is enumerated as /dev/rtc1. As 
such, the clock is wrong on boot.

I used different capes because I was going for firmware already on the BBB. 
I don't see anything about either DTO that explains the difference in 
behavior.

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