Issues with the Silab Gecko Module

I’m trying to flash a Silab MGM210PA32JIA2 module (same used in the Yellow) connected to a raspberry pi 4.
the module is connected to the pi this way:

GPIO 8: TX
GPIO 9: RX
GPIO 10: CTS
GPIO 11: RTS
GPIO 24: !BOOT
GPIO 25: !RESET

I enabled the uart4 with the cts/rts, and the pins configuration looks good:

$ raspi-gpio get 08-11
GPIO 8: level=1 alt=4 func=TXD4 pull=NONE
GPIO 9: level=1 alt=4 func=RXD4 pull=UP
GPIO 10: level=1 alt=4 func=CTS4 pull=UP
GPIO 11: level=0 alt=4 func=RTS4 pull=NONE

The flashing seems to be working correctly (note that I connected the !BOOT pin to the same GPIO used in yellow, so I can use the --bootloader-reset yellow):

$ universal-silabs-flasher --device /dev/ttyAMA4 --bootloader-reset yellow flash --allow-cross-flashing --firmware NabuCasa_Yellow_EZSP_v6.10.3.0_PA32_ncp-uart-hw_115200.gbl
INFO Triggering yellow bootloader
INFO Probing ApplicationType.GECKO_BOOTLOADER at 115200 baud
INFO Launched application from bootloader
INFO Detected bootloader version '1.9.0'
INFO Probing ApplicationType.CPC at 460800 baud
INFO Probing ApplicationType.CPC at 115200 baud
INFO Probing ApplicationType.CPC at 230400 baud
INFO Probing ApplicationType.EZSP at 115200 baud
INFO Probing ApplicationType.SPINEL at 460800 baud
INFO Triggering yellow bootloader
WARNING Bootloader did not launch a valid application
INFO Detected ApplicationType.GECKO_BOOTLOADER, version '1.9.0' at 115200 baudrate (bootloader baudrate 115200)
NabuCasa_Yellow_EZSP_v6.10.3.0_PA32_ncp-uart-hw_115200.gbl [####################################] 100%

Using the --verboseoption I can see the bootloader sends “upload completed succesfully”, then the flasher sends “2” that corresponds to “run application” but from that moment on the serial goes silent:

$ universal-silabs-flasher --device /dev/ttyAMA4 probe
INFO Probing ApplicationType.GECKO_BOOTLOADER at 115200 baud
INFO Probing ApplicationType.CPC at 460800 baud
INFO Probing ApplicationType.CPC at 115200 baud
INFO Probing ApplicationType.CPC at 230400 baud
INFO Probing ApplicationType.EZSP at 115200 baud
INFO Probing ApplicationType.SPINEL at 460800 baud
Error: Failed to probe running application type

If I connect to the serial and set the !BOOT pin to low I see the bootloader prompt:

Gecko Bootloader v1.9.0
1. upload gbl
2. run
3. ebl info
BL > 

Sending 2 or 3 will make the menu be printed again.
Looking up the bootloader documentation option 3 does nothing, option 2 reprints the menù if no application is found or if the last application upload was unsuccessful.

I notice from other people logs that the module shipped with the Yellow have the bootloader version 2.0.1. Can that be the issue?
Do I need to update the bootloader?
In this case how do I do it? Do I need to use the Simplicity Commander?

Suggest post the same question as a new issue to the universal silabs flasher repository on GitHub:

Unsure but bootloader normally needs to be flashed via JTAG using J-Link debug probe and similar.

If on a budget check out Silicon Labs Si-DBG1015A Simplicity Link Debugger and J-Link EDU Mini:

Thanks a lot!
I created the issue there: Flash successful but probe fails · Issue #70 · NabuCasa/universal-silabs-flasher · GitHub

I want have some confirmations that the issue could be the bootloader before investing time and money in the JTAG flasher