On Mon, Jul 24, 2017 at 11:47:47AM -0400, Marti Bolivar wrote:
It's likely future work, but it seems inevitable we'll have to defineI don't think so. Part of the definition of the bootloader needs to
be to describe what state it leaves things in. For most
compatibility, it would seem best to leave things in as close to reset
state as possible. Ideally, that would shut down any clocks, etc.
Unfortunately, when booting apps that do use the serial port, turning
off the clock like this will usually result in gibberish coming over
the serial port. This probably doesn't hurt much, but can be
The Mynewt approach has been to not use the serial port in the
bootloader. We could consider the uart use to be a debugging feature,
and recommend it be turned off for production.
Otherwise, we would want to add code to disable any clocks that were
started. I'm not sure there is an easy way to do this in the mcuboot
code without introducing target-specific code.