The Sweetman book on MIPS is one of the best to learn OS internals from and how exactly it interfaces to the hardware.

Complementing that is the excellent Unix Systems for Modern Architectures: Symmetric Multiprocessing and Caching for Kernel Programmers by Curt Schimmel.

Complementing the Furber book is the excellent Computer System Design: System-on-Chip by Michael Flynn and Wayne Luk.

And of course the classic ARM System Developer's Guide: Designing and Optimizing System Software by Andrew Sloss et al. is also a must read.

Thanks. I'll seek these out next time I get to a university library. I'd like to read more good books on multiprocessing.

Two other OS texts in my collection that I really enjoyed were:

UNIX Internals: The New Frontiers

by Uresh Vahalia

https://openlibrary.org/works/OL2938389W/Unix_Internals

and,

The Design and Implementation of the 4.4 BSD Operating System

by McKusick, Bostic, Karels, and Quarterman

https://openlibrary.org/works/OL19501888W/The_design_and_imp...