Sharing EXTI interrupt between A7 and M4 cores.

OskarM · ‎2025-07-08

Hi,

is there any way to share an external interrupt, coming from two separate GPIOs, between M4 and A7 cores in stm32mp15x family?

thanks

Olivier GALLIEN · ‎2025-07-18

Hi @OskarM ,

Sorry can you please add further contex and detail about your question ?

Thanks

Olivier

Olivier GALLIEN
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OskarM · ‎2025-07-22

Olivier,

the general context is that we almost used out all GPIOs and we have a conflict between M4 and A7 cores on one EXTI "signal". In cores like M4 and any other, simpler cores, when both GPIOs are on the same core, you could just read the current state of both GPIO lines in the interrupt routine and decide which GPIO triggered the acutal EXTI interrupt, provided that we have some knowledge (control) on the external trigger duration etc. It's not perfect, but it's possible to do. Now, when the same situation happens on two, separate cores, each core would have to be triggered on the same EXTI interrupt, maybe use HSEM to protect EXTI registers from clearing the INT flag or...? Quite complicated I guess.

b.r.