Need help on memory_banks.json for custom targets

[wdx04]

Hi, I have several custom boards which used to work, but failed to build after the Mbed Memory Bank Information PR was merged.

For example, when building an application for my STM32F407ZG board, I got the following error:

[build] memap.py: error: argument -m/--memory-banks-json: C:/Develop/Mbed/mbed-ce-app/build/STM32F407ZG_M144Z-Develop/memory_banks.json does not exist in the filesystem.

It seems that a custom target should have a memory_banks.json file, unless the memory bank information of its MCU is already included in the cmsis_mcu_descriptions.json5 file.

Questions:

1. Is there an existing example of 'memory_banks.json'?
2. Where should I put the 'memory_banks.json'? It seems to be not good to put it directly into a 'build' folder.
3. Currently, startup file and linker script for STM32F407xG do exist in the Mbed targets source tree, but the memory bank information of STM32F407xG is not included in the cmsis_mcu_descriptions.json5 file. This is also true for many other STM32 targets, where there is no supported board for that MCU family. This is not very convenient for custom board users. Does it make sense to add the memory bank information for those MCU families to the cmsis_mcu_descriptions.json5 file?

Thanks.

[multiplemonomials]

Ah, this should not be causing a build error like this, that is a bug and I will take a look

You should be able to supply memory banks information directly in custom_targets.json via a memory_banks attribute. There's an example of this in the memory banks wiki page under the "Adding Flash Information to RP2040" section