Arm Architecture: Memory Model and Barriers [Author's Lecture Part 3-3]

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1. 30% discount coupon issued when 200 people sign up

To celebrate reaching 200 students (Part 1 and 2), we are issuing a 30% discount coupon. Thank you. First 100 people.

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2. Roadmap Guide 🎯

This lecture is a roadmap 'Arm - advanced course for system software developers ' This lecture is included in .

If you want to learn Arm architecture (Armv8-A, Armv7-A) systematically , it is recommended to use the roadmap ( 30% discount on all lectures ). For reference, the Arm architecture roadmap (all author lectures) is Basic Course and Advanced Course It consists of two parts.

In the latest system software
The most important Arm architecture

The Arm processors used in smartphones, AI SoC system semiconductors, electric vehicles (autonomous driving, infotainment), cloud servers, and MacBooks are all Armv8-A based 64-bit Cortex-A processors (Cortex-A53, Cortex-A57, Cortex-A72, etc.). It can be said that the area requiring the most basic knowledge in the current system software industry is the Armv8-A architecture.

The first step to becoming an advanced system SW developer!
Understanding memory management methods 🙋‍♂

However, in order to become an advanced system software developer, you need to understand how to manage memory, which is one of the main functions that make up the Arm architecture. The core of how to manage memory is the 'virtual memory system', 'cache operation principles', and 'memory model and barrier' .

Why learn 'Memory Model and Barrier'?

1⃣ First, if you know the memory model and barriers well, you can develop a good device driver . Most device drivers control peripheral devices in a memory-mapped I/O manner, and the memory model (normal memory, device memory) covers device memory, which is the basis of the memory-mapped I/O method, in detail.

2⃣ Second, you need to understand the device memory (one of the memory models), which is the basis of memory-mapped I/O, to be able to efficiently control the hardware that makes up the system semiconductor in programming. This is because most independent modules (IPs) that make up the system semiconductor are designed using the memory-mapped I/O method in system semiconductors (fabless).

3⃣ Third, if you know the memory model and barriers well, you can understand the working principles inside the Arm processor in detail . In particular, you will often encounter situations where barriers are used to solve concurrency problems in multi-core systems, and 'memory models and barriers' can be basic knowledge.

4⃣ Fourth, in order to do well in technical interviews related to system software development, you need to know 'memory models and barriers' well. One of the questions that comes up frequently in interviews for experienced developers is about memory reordering and memory-mapped I/O.

A lecture directly written by the author containing the know-how of a 12-year system engineer!

The book 'Arm Architecture Structure and Principles for System Software Development' (Chapter 17) covers 'Memory Model and Barrier' in detail. I hope that you will grow further as a system software developer through the author's lectures.

Learn about these things

Introduces the types of memory models defined in the Arm architecture and normal memory.

By analyzing the Arm specification document in detail, we introduce the types of memory models (normal memory and device memory).

We will detail the device memory, which is a memory-mapped I/O interface, and review the memory-mapped I/O of the BCM2711 (used on a Raspberry Pi).

Analyzing memory-mapped I/O interfaces with debugging (Crash-Utility).

Introduces barriers and provides detailed examples of barriers.

Describes the scope of barriers and data consistency in multi-core systems.

This article details how barriers are actually utilized in the Linux kernel and XEN hypervisor.

Based on my experience writing books and giving lectures
More in-depth and detailed than anyone else!

The author of the unprecedented 'Arm Architecture (Armv8-A, Armv7-A)' and 'Linux Kernel' books in the domestic system software field. He is also a working developer who knows the latest system software trends (electric vehicles, system semiconductors - system software) the best, and an educator who is most active in spreading knowledge in the system software field.

• Author of 'Structure and Principles of Arm Architecture for System Software Development' ( 2024, Korean Academy of Sciences Outstanding Book Award )

• Author of 'Learning the Structure and Principles of the Linux Kernel through Debugging' ( 2021, Korean Academy of Sciences Outstanding Book Award )

• 'Programmers Dev Course: Linux System and Kernel Expert' Main Instructor

• June 2022, Korea Computer Conference (KCC2022) - Tutorial presentation [Conquering the Linux Kernel using ftrace]

• LG Electronics 'Linux Kernel' and 'Armv8 Architecture' In-house Instructor ( including domestic and overseas developers ) - (2020~2024)

I can confidently say that I am the educator who can explain the key features of the Arm architecture (Armv8-A, Armv7-A) better than anyone else in Korea.

Vivid course reviews left by students

<Structure and Principles of Arm Architecture for System Software Development - Part 1/2 Author's Lecture>

Things to note before taking the class