'esp_wake_deep_sleep' GPIO ISR initialization

[malachib]

Similar to what's going on here viewtopic.php?t=1674

I would like to register a GPIO-listening ISR as soon as I get an EXT1 deep sleep wakeup. Is it possible to use something like gpio_isr_handler_add within esp_wake_deep_sleep?

[ESP_igrr]

No, the earliest you can register a GPIO ISR is when app_main starts. When deep sleep wake stub is running, FreeRTOS has not started yet, so interrupt servicing using the driver is not possible.

[malachib]

OK, that is helpful to know, thank you.

Presumably one can hook into a bare-metal ISR at this point? My concern would then be: does FreeRTOS blast it away on startup?