ESP2S2: Resetting either programmatically or via watchdog causes device to go into SAFE_MODE

[dheera]

Running this:

import microcontroller
microcontroller.on_next_reset(microcontroller.RunMode.NORMAL)
microcontroller.reset()

causes the board to reset and go into safe mode instead of normal mode.

Similarly, setting up a watchdog with the following code.py:

from microcontroller import watchdog as w
from watchdog import WatchDogMode
w.timeout = 10.0
w.mode = WatchDogMode.RESET
w.feed()
while True:
    pass

causes the microcontroller to reset after 10.0 seconds (as expected), but the microcontroller resets into safe mode instead of resetting and re-running code.py, which is the usual intent of watchdog usage.

Product: FeatherS2
CircuitPython version: adafruit-circuitpython-unexpectedmaker_feathers2-en_US-6.1.0-beta.3.uf2

Related but not same issue: #3884

[microdev1]

There are two different issues here :-

1. microcontroller.on_next_reset() :- Only RunMode.SAFE_MODE is currently implemented.
2. The watchdog reset gets caught here :-
   

   circuitpython/ports/esp32s2/supervisor/port.c

   Lines 142 to 151 in 92a4398

   	switch (reason) {
   	case ESP_RST_BROWNOUT:
   	return BROWNOUT;
   	case ESP_RST_PANIC:
   	case ESP_RST_INT_WDT:
   	case ESP_RST_WDT:
   	return HARD_CRASH;
   	default:
   	break;
   	}

[dhalbert]

microcontroller.reset() works for me if I use the .bin, but not if TinyUF2 is present.

[dhalbert]

The reason is stored in a supposedly "reserved by ESP-IDF". Check if TinyUF2 is using the same RTC register as CircuitPython. Try a different one?

[dheera]

I believe this was already resolved by this pull request I made that was accepted
#4011
Thanks!

[dhalbert]

I believe this was already resolved by this pull request I made that was accepted

Thanks! We think there may still be a problem with UF2 builds and will re-test.

[ThinkTransit]

Hi,

I have tested this on the nightly build from last night - Adafruit CircuitPython 7.0.0-alpha.5-175-g8da98eb1f on 2021-08-10; FeatherS2 with ESP32S2

microcontroller.reset() works as expected however resetting from the watchdog still goes to safe mode on the FeatherS2

[FlorianBaumgartner]

Yes, same problem as @ThinkTransit described. My setup: Adafruit ESP32-S2 Metro, UF2 (0.5.2), cpy (7.0.0).
It's impossible to boot into the UF2-Bootloader from user code. Either by using circuit python:

import microcontroller
microcontroller.on_next_reset(microcontroller.RunMode.UF2)
microcontroller.reset()

or directly in Arduino CPP:

esp_reset_reason();
esp_reset_reason_set_hint((esp_reset_reason_t) 0x11F2);
esp_restart();

It acts just as a regular reset (single button press). By reading the reset reason I always get: "RTCWDT_RTC_RESET"

[FlorianBaumgartner]

Problem has been solved. The UF2 Bootloader must be completely reinstalled to update all partitions.
#5426