previously we just panic'd (which is actually the right behavior
for this type of error) but because we now have a reason for it
to fail (e.g. testing the encryption key) we make this fallible.
in all other places we just unwrap() - there is no fallback if
decryption fails, boot should just halt.
but this allows us to check which decryption key is deployed
in phase 1.
- loader heap is now fixed in a "throw-away" region of memory.
this means the heap should only be used sparingly, and somewhat
dangerously, because the values can't persist beyond the lifetime
of the loader.
- signature validation moved earlier
- fixup swap structures to refer to the API so that image creation
is easier/consistent
this is a fairly complicated bit of legacy code that we're
trying to make slightly better/more readable.
some docs are added, as well as getting rid of a bunch of
"magic" constants, instead preferring to map things into
structured data where possible.
also fixed the location of the heap allocation relative to
the boot flow. It's now in a spot where I think we can
safely put dynamically allocated kernel arguments.
The loader grew a lot of hair over the past few months as it
was abused as a baremetal environment for chip bring-up.
A baremetal environment was explicitly created to help with that,
so we don't have to pollute the loader with lots of unused features
and ancilliary code.
Furthermore, a decision was made to eliminate updates from the
loader code base - the loader is just for setting up Xous. This
allows the loader to be more platform-agnostic.
Boot1 instead contains all the platform-specific code for doing updates.
For completeness, we note that boot0 is a minimal piece of code that is the
first step in the chain of trust and is intended to be a read-only
segment of code that has public keys baked into it that are used
to bootstrap the rest of the ecosystem.
At this point, the loader is now slimmed down and runs. Still needs
testing to make sure the culling wasn't too aggressive, but I am
much happier with where this is landing as the loader is once again
just focused on getting Xous up and running.
The code base had evolved through several code names, interim
names, company names and chip names that alternatively did or did
not exist.
Baochip is the definitive name of the company, and the Baochip1x
(full part number BAO1X2S4F-WA) is the definitivey part number of
the SoC. For convenience, the part number is shortened to 'bao1x'
in most feature flags and variable references.
This commit fixes all of the odd names and removes some unmaintained
early targets.
the switch based on target is now absorbed into the new() function.
This paves the way for us to add more CSR ranges into the global
configuration object, i.e. IRQ csrs for I2C.
add a note about the dirty flag - it's not "dead" per se, I
think it is helpful to leave a bread crumb for future hw revs
that might have hardware-enforced dirty bit setting on the PTE.
KB_C2 pin on this test board just got shorted to ground internally
in the chip. I think it may have been due to power glitches
when the ammeter was switching modes feeding through and causing
trouble for the system.
Anyawys, disable that row and remap some keys so we can continue
with testing. MPW boards will hopefully be retired soon enough...
This loop was useful in bringing up the GC2145 camera, so
we should keep this code around. had to be refactored/shuffled
around a bit to compensate for e.g. bitrot.
