Here is a list of all documented files with brief descriptions:

sdk
include
ds
bits.h	Bit manipulation utilities
linked_list.h	A (circular) doubly linked list, abstracted over cons cell representations
pointer.h	Pointer utilities
ring_buffer.h	Ring/circular buffer state machine
xoroshiro.h	Pseudo random number generator based on Xoroshiro algorithm
FreeRTOS-Compat	A (mostly complete) compatibility layer for core FreeRTOS APIs
event_groups.h	FreeRTOS event-group compatibility APIs
FreeRTOS.h	FreeRTOS porting layer
FreeRTOS_errno.h	FreeRTOS-compatible errno values
queue.h	FreeRTOS queue compatibility APIs
semphr.h	FreeRTOS semaphore compatibility layer
stream_buffer.h	FreeRTOS stream compatibility APIs
task.h	Minimal FreeRTOS task compatibility APIs
microvium
microvium_port.h	Port specific definitions for port of Microvium to CHERIoT RTOS
platform
arty-a7
platform-entropy.hh
platform-ethernet.hh
platform-gpio.hh
concepts
entropy.h	Concept for an Entropy sources and a trivial, insecure implementation using xoroshiro PRNG
ethernet.hh
hardware_revoker.hh
uart.hh
generic-riscv
platform-entropy.hh
platform-plic.hh
platform-rdcycle.h
platform-simulation_exit.hh
platform-time.h	` defines the interface for the timer that is used to implement a monotonic clock
platform-timer.hh
platform-uart.hh
ibex
ibex-csr.h	Ibex defines some custom M-mode CSRs to control some of its extensions:
platform-hardware_revoker.hh
platform-rdcycle.h
kudu
platform-rdcycle.h
microsoft_cheriot_safe
platform-simulation_exit.hh
sail
platform-rdcycle.h
sunburst
v0.2
platform-ethernet.hh
platform-gpio.hh
platform-i2c.hh
platform-spi.hh
platform-adc.hh
platform-early_boot.inc
platform-entropy.hh
platform-ethernet.hh
platform-gpio.hh
platform-i2c.hh
platform-pinmux.hh
platform-pwm.hh
platform-rgbctrl.hh
platform-simulation_exit.hh
platform-spi.hh
platform-uart.hh
platform-usbdev.hh
synopsis
platform-uart.hh
priv
riscv.h
revoker
bitmap_direct.hh
__cheri_sealed.h
__compartment-macros.h	Helper macros used by compartment-macros.h
__debug.h
__macro_map.h
allocator.h	CHERIoT RTOS heap allocator interface
assembly-helpers.h	Helpers for exposing field offsets and structure sizes into assembly
assert.h
bitpack.hh
cdefs.h
cheri-builtins.h
cheri.h	C definitions for CHERI specific functionality
cheri.hh	C++ helpers for operating on capabilities
compartment-macros.h	Macros for interacting with the compartmentalisation model in CHERIoT
compartment.h
ctype.h	ASCII-only definition of C standard C functions
debug.h
debug.hh	C++ APIs for assertions, invariants, and writing formatted debug messages to a UART
errno.h
event.h	Event-group APIs
fail-simulator-on-error.h
float.h
float_to_string_helpers.hh
function_wrapper.hh
futex.h	Futex (compare-and-wait) APIs
interrupt.h	This file describes the interfaces for compartments to wait for interrupts
inttypes.h
limits.h
locks.h	C compatible interface to synchronisation primitives
locks.hh	C++ wrappers for synchronisation primitives
multiwaiter.h	This file provides interfaces to the multi-waiter system
queue.h	This file contains the interface for a simple message queue
randombytes.h	API for accessing a shared entropy source in the randombytes compartment
ring_buffer.hh
riscvreg.h
setjmp-assembly.h
setjmp.h
simulator.h
stdalign.h
stdarg.h
stdatomic.h	This file implements the C11 and C++23 C atomics interfaces
stdbool.h
stddef.h
stdint.h
stdio.h
stdlib.h
stdnoreturn.h
string.h
strings.h
switcher.h	APIs for interacting with the switcher
thread.h	Functions and types used for thread management
thread_pool.h	APIs for an example thread pool
tick_macros.h
time.h
timeout.h	This file contains the types used for timeouts across scheduler APIs
timeout.hh
token.h	APIs for dealing with type-safe opaque handles (sealed objects)
unwind-assembly.h
unwind.h	APIs for synchronously handling traps
utils.hh	Miscellaneous utility functions and classes