[ryanclem]

Thank you!! I must not have searched the -SM specific forum before posting this. That thread was very helpful in diagnosing my problem.

To help anyone else in the future –
My issue was that the RTC oscillator (OSC1) was not starting up properly. I had not noticed that on the OSD3358-C-Sip-RED schematic that R24 (1M resistor in parallel with 32k crystal Y1) was DNI. Apparently the RTC has an internal resistor that is used by default in most images and the R24 is not needed and will inhibit the oscillator from functioning properly. (https://e2e.ti.com/support/processors/f/791/t/316906?AM335X-External-RTC-crystal-doesn-t-oscillate-)

[ryanclem]

Very clear! Thank you for the detailed response.

[ryanclem]

I noticed that the src/arm directory in my image has an am335x-osd3358-sm-red.dts that seems to be compatible with the CSIP. My boards aren’t in yet so I can’t confirm it will actually work, but my plan is to modify that file to create my custom device tree for my custom board.

For what it’s worth I was able to get their dts to compile for 4.19-ti by changing the following:

1) Add #include <dt-bindings/pinctrl/am33xx.h> to the top of osd335x-sm.dtsi
2) At the bottom of osd335x-sm.dtsi change /include/ “am33xx-clocks.dtsi” to #include “am33xx-clocks.dtsi”
3) In bsm-refdesign.dts in the &rtc section change clkdiv32k_ick to clkdiv32k_ck

I ended up getting a lot of warnings and since my boards aren’t ready for testing yet so I don’t know if it will end up working as expected on an actual target.

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