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pyocd / pyOCD

Open source Python library for programming and debugging Arm Cortex-M microcontrollers
https://pyocd.io
Apache License 2.0
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Option to disable overriding of security #722

Open embed opened 5 years ago

embed commented 5 years ago

When flashing a Kinetis device, pyOCD overrides the Flash Configuration Field with safe defaults, in order to avoid breaking/bricking the device. This is implemented as the method override_security_bits.

This behaviour should be optional (and enabled by default, to be safe) and switchable via a command line option, so developers can implement their custom security settings.

flit commented 5 years ago

Good idea, thanks. This would be handled by a user option, so from the command line it would look something like -Oflash.override_security_bits=no.

embed commented 4 years ago

I can implement this but I am not familiar with the source. Can someone point me where the command line options are listed and parsed?

flit commented 4 years ago

The best way to implement this is to add a user option as described in the comment above.

  1. First add the option definition:

    • Add the definition to pyocd/core/options.py.
    • Document the option in docs/configuration.md.

    This documents the option, sets its type, and sets the default value. The option can now be set on the command line with the -O argument.

  2. Next, handle the option in the Flash class methods by skipping the call to self.override_security_bits(...) when enabled. To get the option value, use the self.target.session.options.get('flash.override_security_bits').

Unfortunately, there's not really a good way to automatically test it right now, as target-specific tests aren't supported (yet). So no additions to the functional tests are required.