After ESP32S3 uses UF2 to install micropython firmware, the file system reports error

[Wind-stormger]

I opened an issue on Mar 25 #8453.
Maybe I could come here to ask a question and discuss this.

Briefly:

1. Get a UF2 firmware that supports EPS32S3 from here adafruit/tinyuf2/releases, use esptool to install it (0x0 combined.bin).
2. Get a micropython firmware with .uf2 extension that supports EPS32S3 from here https://micropython.org/download/, copy the .uf2 file to UF2 BootLoader as you would with rp2040.
3. Use any tool that has access to the REPL, such as mpremote, enter REPL, soft reset, get the following error:

>>>
MPY: soft reboot
Performing initial setup
Traceback (most recent call last):
  File "_boot.py", line 11, in <module>
  File "inisetup.py", line 36, in setup
OSError: [Errno 22] EINVAL
MicroPython v1.19.1 on 2022-11-14; ESP32S3 module (spiram) with ESP32S3
Type "help()" for more information.
>>>

The error message points to this piece of code, which is used to format the entire flash using littlefs v2.

micropython/ports/esp32/modules/inisetup.py

Lines 33 to 38 in d9bca30

	def setup():
	check_bootsec()
	print("Performing initial setup")
	uos.VfsLfs2.mkfs(bdev)
	vfs = uos.VfsLfs2(bdev)
	uos.mount(vfs, "/")

But the file system format used by UF2 is FAT, so here is error.

[Wind-stormger]

Solved by manually formatting to FAT filesystem, but could there be a better way?

>>> os.VfsFat.mkfs(bdev)
>>> os.mount(bdev,'/')
>>>
MPY: soft reboot
MicroPython v1.19.1 on 2022-11-14; ESP32S3 module (spiram) with ESP32S3
Type "help()" for more information.
>>>

[Wind-stormger]

Whenever people download micropython firmware, at the top of the list is the UF2 firmware.

But in the UF2 Bootloader, if you have not installed the circuitpython.uf2 firmware before, but directly installed the micropython.uf2, this error must occur.

Performing initial setup
Traceback (most recent call last):
  File "_boot.py", line 11, in <module>
  File "inisetup.py", line 40, in setup
OSError: [Errno 22] EINVAL

I want to add code that can format the partition as fat in ports/esp32/modules/inisetup.py.

micropython/ports/esp32/modules/inisetup.py

Lines 37 to 53 in ca79b49

	def setup():
	check_bootsec()
	print("Performing initial setup")
	os.VfsLfs2.mkfs(bdev)
	vfs = os.VfsLfs2(bdev)
	os.mount(vfs, "/")
	with open("boot.py", "w") as f:
	f.write(
	"""\
	# This file is executed on every boot (including wake-boot from deepsleep)
	#import esp
	#esp.osdebug(None)
	#import webrepl
	#webrepl.start()
	"""
	)
	return vfs

like this:

def setup():
    from esp32 import Partition
    check_bootsec()
    print("Performing initial setup")
    if Partition.info(bdev)[4] == "vfs":
        os.VfsLfs2.mkfs(bdev)
        vfs = os.VfsLfs2(bdev)
    elif Partition.info(bdev)[4] == "ffat":
        os.VfsFat.mkfs(bdev)
        vfs = os.VfsFat(bdev)
    os.mount(vfs, "/")
    with open("boot.py", "w") as f:
        f.write(
            """\
# This file is executed on every boot (including wake-boot from deepsleep)
#import esp
#esp.osdebug(None)
#import webrepl
#webrepl.start()
"""
        )
    return vfs

@robert-hh , @jimmo

Would you please，could I submit a PR on this?

[peterhinch]

The instructions suggest using esptool.py, with the command line specifying the .bin file. This has always worked perfectly for me.

[Wind-stormger]

Yes, I did that too.

I'm just trying to get .uf2 to work as well. 😃