A fair bit of reshuffling with include paths and overrides was necessary, as
the two RTOS SDKs (ESP8266 and ESP32) don't have the same header structure
(or even libraries for that matter). Uses the xtensa-esp108-elf toolchain
to build.
Completely untested beyond linking, as I still can't flash the ESP32 module
I have :( I'd be most surprised if it does anything useful at this point
considering I've spent almost no time on the linker script or UART setup.
Anything using espconn has been ifdef'd out since espconn is not (and
probably will not be) available. Notably this includes the entire net module
as well as coap, mqtt and enduser_setup.
Many (most?) hardware bus drivers and related modules are also ifdef'd
out for now due to hardware differences. Functions surrounding sleep,
rtc and RF modes have also been hit by the ifdef hammer. Grep'ing for
__ESP8266__ and/or FIXME is a quick way of finding these places. With
time I hope all of these will be reinstated.
This compiles, links, and starts the RTOS without crashing and burning.
Lua environment does not yet start due to the different task architecture.
Known pain points:
- task implementation needs to be rewritten for RTOS (next up on my TODO)
- secure espconn does not exist, all secure espconn stuff has been #if 0'd
- lwip now built from within the RTOS SDK, but does not appear to include
MDNS support. Investigation needed.
- there is no access to FRC1 NMI, not sure if we ever actually used that
however. Also #if 0'd out for now.
- new timing constraints introduced by the RTOS, all use of ets_delay_us()
and os_delay_us() needs to be reviewed (the tsl2561 driver in particular).
- even more confusion with ets_ vs os_ vs c_ vs non-prefixed versions.
In the long run everything should be switched to non-prefixed versions.
- system_set_os_print() not available, needs to be reimplemented
- all the RTOS rodata is loaded into RAM, as it apparently uses some
constants while the flash isn't mapped, so our exception handler can't
work its magic. This should be narrowed down to the minimum possible
at some point.
- with each task having its own stack in RTOS, we probably need change
flash-page buffers from the stack to the heap in a bunch of places.
A single, shared, page buffer *might* be possible if we limit ourselves
to running NodeMCU in a single task.
- there's a ton of junk in the sdk-overrides now; over time the core code
should be updated to not need those shims
Johny Mattsson
Johny Mattsson