Book Image

Modern Computer Architecture and Organization – Second Edition - Second Edition

By : Jim Ledin
Book Image

Modern Computer Architecture and Organization – Second Edition - Second Edition

By: Jim Ledin

Overview of this book

Are you a software developer, systems designer, or computer architecture student looking for a methodical introduction to digital device architectures, but are overwhelmed by the complexity of modern systems? This step-by-step guide will teach you how modern computer systems work with the help of practical examples and exercises. You’ll gain insights into the internal behavior of processors down to the circuit level and will understand how the hardware executes code developed in high-level languages. This book will teach you the fundamentals of computer systems including transistors, logic gates, sequential logic, and instruction pipelines. You will learn details of modern processor architectures and instruction sets including x86, x64, ARM, and RISC-V. You will see how to implement a RISC-V processor in a low-cost FPGA board and write a quantum computing program and run it on an actual quantum computer. This edition has been updated to cover the architecture and design principles underlying the important domains of cybersecurity, blockchain and bitcoin mining, and self-driving vehicles. By the end of this book, you will have a thorough understanding of modern processors and computer architecture and the future directions these technologies are likely to take.
Table of Contents (21 chapters)
18
Other Books You May Enjoy
19
Index

Privileged processor modes

Most operating systems running on 32-bit and 64-bit processors control access to system resources using the concept of privilege levels. The primary reasons for managing access in this manner are to enhance system stability, prevent unauthorized interactions with system hardware, and prevent unauthorized access to data.

Privileged execution improves system stability by ensuring only trusted code is allowed to execute instructions that provide unrestricted access to resources such as processor configuration registers and I/O devices. The operating system kernel and related modules, including device drivers, require privileged access to perform their functions. Because any crash of a kernel process or a device driver is likely to halt the entire system immediately, these software components generally undergo a careful design process and rigorous testing before being released for general use.

Running the operating system in a privileged context prevents...