The latest Linux processor SDK version 6 supports 1PPS signals on both GMAC and PRU HSR/PRP ports. The test setup for 1PPS measurements using IDK is well documented. But it explains 1PPS inputs (latch) for PTP BC (Boundary Clock) only when, say, GMAC clock can sync to PRU clock or vice verse, and BC driver controls the direction.
In my setup I do not need the BC. I want to have ordinary clock PTP master on any of interfaces (GMAC or PRP/HSR) which is driven by external GPS 1PPS signal: GPS 1PPS -> PRU/GMAC 1PPS latch. This configuration is not documented.
Standard Linux way is to route 1PPS via GPIO (or other port pins). It is hardware independent, but it uses GPIO interrupts and involves kernel. This will have unacceptable jitter. So a hardware 1PPS processing using timers is much better, but is this supported? Will 1PPS inputs work if fed to latch inputs to sync PTP clocks without BC driver? I do not need to control which 1PPS is active (what BC driver does). But I am not sure if this configuration is possible and guaranteed to work.
