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The USRP™ Hardware Driver Repository
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e320: Ensure GPSDO is cleanly reset upon radio power-on #757

Closed draeman-synoptic closed 3 months ago

draeman-synoptic commented 3 months ago

This patch performs an explicit reset on the GPSDO when the E320 MPM service is initialized upon boot. This ensures the GPSDO HW is always in a known power-on reset state when MPM starts up.

Description

It's worth noting that this PR doesn't address a specific known problem, but rather was a way to ensure the GPSDO HW is always brought into a known reinitialized state upon startup, using MPM functions that manage HW state. Previously initial pin levels were simply set when the FPGA is loaded, which may differ in timing/sequencing from MPM pin control logic.

I was on the fence about submitting as a PR since any benefit is unclear at best, but figured I'd defer to your judgement. I needed to ensure GPS was being initialized consistently across a cluster of E320 radios including upon soft reboot.

Which devices/areas does this affect?

MPM running on USRP E320.

Testing Done

Confirmed GPSDO operates as expected upon power-up. Confirmed GPSDO undergoes a HW reset if the USRP MPM service is restarted on the radio.

Checklist