New version of the Cortex-A Series Programmer's Guide is Available

The ARM® Cortex®-A Series Programmer’s Guide has proved to be a very popular addition to the ARM documentation set, and now also forms the reference textbook for the ARM Accredited Engineer(AAE) examinations.

The updated ARM® Cortex®-A Series Programmer’s Guide (requires registration for an ARM account) is still for programmers using ARM Cortex-A series processors conforming to the ARMv7-A architecture, but you will find some sections moved, some extensively rewritten, and some with minor changes:

• The chapter on Registers has been largely rewritten to include the effects of the Security and Virtualization Extensions and the introduction of Privilege levels.
• Chapters that covered the same areas have been combined. The chapters on Exception Handling have been consolidated, so that they now tell a coherent story. A similar approach has been applied to multiprocessing and parallelization.
• The Large Physical Address Extension(LPAE) is now covered in the chapter on Virtualization.
• The chapter on big.LITTLE technology has been extensively revised to keep pace with rapidly changing technology.
• ARM has added another processor to the ARMv7 Cortex-A series, and the new Cortex-A12 processor is covered in this new edition.
• The NEON/VFP Appendix and the chapter on Writing NEON Code have been removed. We said that the information on NEON would need a book of its own. It now has that in the form of the NEON™ Programmer’s Guide.
• Additional information has also been provided in the form of programming hints and tips, for developers using the Cortex-A series processors. While these cannot cover everything, we hope the included examples will prove useful to explain the concepts and give you a starting point to a bigger project.

You will also notice that what we call the devices has changed. The terms CPU and processor were ambiguous so:

• Processor now only refers to the marketed device, such as the Cortex®-A15 processor,
• Core refers to a single implementation of a processor. This was sometimes called a CPU in the past.
• Clusters are groups of multiple cores sharing an L2 cache
• A big.LITTLE system typically refers to two clusters of cores, although it could be a single big core and a cluster of several LITTLE cores.

The programmer's guide complements rather than replaces other ARM documentation for the Cortex-A series processors.

For information on a specific processor, see the appropriate ARM Technical Reference Manual:

• ARM® Cortex®-A7 MPCore Technical Reference Manual
• ARM® Cortex®-A8 Technical Reference Manual
• ARM® Cortex®-A9 Technical Reference Manual
• ARM® Cortex®-A15 MPCore Processor Technical Reference Manual.

The most important and definitive reference for the ARMv7A architecture remains the ARM® Architecture Reference Manual ARMv7-A and ARMv7-R edition.