System Register XML
for Armv9
(2021-03)

31 March 2021


1. Introduction

This is the 2021-03 release of the System Register XML for Armv9 describing:

The Proprietary Notice gives details of the terms and conditions under which this package is provided.

If you have comments on the content of this package, please send them by e-mail to support@arm.com. Give:

Please see the Documentation for more information on the general structure of these descriptions.

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2. Contents

This Version 2021-03 [HTML] [PDF] [XML]

3. Release notes

Armv9 change history

Armv9 known issues

Armv8.7 change history

Known issues

All issues identified in the below list would be fixed in a future release.

Potential upcoming changes

We are looking in improvements to the information that is provided in the XML. In some cases these changes may impact users. Here is a list of areas where we may make change in a future release:


4. Documentation

General

A description within the XML contains the following sections:

Purpose
A short description of the purpose of the register in the Architecture.
Configuration
How the register is architecturally mapped onto another System register or a memory-mapped register. If the configuration of the PE affects the implementation of the register, then information about this is also included here. This section also summarizes the behavior of the register on a reset.
Attributes
The size of the register. For registers where the layouts of the fields differ based on configuration, or other state within the PE, this section also summarizes the different layouts.
Field descriptions
The register diagram, and a description of the behavior of each field within the register.

Memory-mapped registers

A memory-mapped register description also contains the following sections:

Accessing the ...
The address or offset of the register in the memory map, and the accessibility.

System registers

A System register description also contains an "Accessing the ..." section, that includes: