Copyright © 2015 ARM. All rights reserved.
ARM DEN0024A (ID050815)
ARM
®
Cortex
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-A Series
Version: 1.0
Programmer’s Guide for ARMv8-A
ARM DEN0024A Copyright © 2015 ARM. All rights reserved. ii
ID050815 Non-Confidential
ARM Cortex-A Series
Programmer’s Guide for ARMv8-A
Copyright © 2015 ARM. All rights reserved.
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Contents
ARM Cortex-A Series Programmer’s Guide for
ARMv8-A
Preface
Glossary ...................................................................................................................... ix
References ............................................................................................................... xiii
Feedback on this book ............................................................................................... xv
Chapter 1 Introduction
1.1 How to use this book ............................................................................................... 1-3
Chapter 2 ARMv8-A Architecture and Processors
2.1 ARMv8-A ................................................................................................................. 2-3
2.2 ARMv8-A Processor properties ............................................................................... 2-5
Chapter 3 Fundamentals of ARMv8
3.1 Execution states ...................................................................................................... 3-4
3.2 Changing Exception levels ...................................................................................... 3-5
3.3 Changing execution state ........................................................................................ 3-8
Chapter 4 ARMv8 Registers
4.1 AArch64 special registers ........................................................................................ 4-3
4.2 Processor state ........................................................................................................ 4-6
4.3 System registers ...................................................................................................... 4-7
4.4 Endianness ............................................................................................................ 4-12
4.5 Changing execution state (again) .......................................................................... 4-13
4.6 NEON and floating-point registers ......................................................................... 4-17
Contents
ARM DEN0024A Copyright © 2015 ARM. All rights reserved. v
ID050815 Non-Confidential
Chapter 5 An Introduction to the ARMv8 Instruction Sets
5.1 The ARMv8 instruction sets ..................................................................................... 5-2
5.2 C/C++ inline assembly ............................................................................................. 5-9
5.3 Switching between the instruction sets .................................................................. 5-10
Chapter 6 The A64 instruction set
6.1 Instruction mnemonics ............................................................................................. 6-2
6.2 Data processing instructions .................................................................................... 6-3
6.3 Memory access instructions .................................................................................. 6-12
6.4 Flow control ........................................................................................................... 6-19
6.5 System control and other instructions .................................................................... 6-21
Chapter 7 AArch64 Floating-point and NEON
7.1 New features for NEON and Floating-point in AArch64 ........................................... 7-2
7.2 NEON and Floating-Point architecture .................................................................... 7-4
7.3 AArch64 NEON instruction format ........................................................................... 7-9
7.4 NEON coding alternatives ..................................................................................... 7-14
Chapter 8 Porting to A64
8.1 Alignment ................................................................................................................. 8-3
8.2 Data types ................................................................................................................ 8-4
8.3 Issues when porting code from a 32-bit to 64-bit environment ................................ 8-8
8.4 Recommendations for new C code ........................................................................ 8-10
Chapter 9 The ABI for ARM 64-bit Architecture
9.1 Register use in the AArch64 Procedure Call Standard ............................................ 9-3
Chapter 10 AArch64 Exception Handling
10.1 Exception handling registers .................................................................................. 10-4
10.2 Synchronous and asynchronous exceptions ......................................................... 10-7
10.3 Changes to execution state and Exception level caused by exceptions ............. 10-10
10.4 AArch64 exception table ...................................................................................... 10-12
10.5 Interrupt handling ................................................................................................. 10-14
10.6 The Generic Interrupt Controller .......................................................................... 10-17
Chapter 11 Caches
11.1 Cache terminology ................................................................................................. 11-3
11.2 Cache controller ..................................................................................................... 11-8
11.3 Cache policies ....................................................................................................... 11-9
11.4 Point of coherency and unification ....................................................................... 11-11
11.5 Cache maintenance ............................................................................................. 11-13
11.6 Cache discovery .................................................................................................. 11-18
Chapter 12 The Memory Management Unit
12.1 The Translation Lookaside Buffer .......................................................................... 12-4
12.2 Separation of kernel and application Virtual Address spaces ................................ 12-7
12.3 Translating a Virtual Address to a Physical Address ............................................. 12-9
12.4 Translation tables in ARMv8-A ............................................................................ 12-14
12.5 Translation table configuration ............................................................................. 12-18
12.6 Translations at EL2 and EL3 ............................................................................... 12-20
12.7 Access permissions ............................................................................................. 12-23
12.8 Operating system use of translation table descriptors ........................................ 12-25
12.9 Security and the MMU ......................................................................................... 12-26
12.10 Context switching ................................................................................................. 12-27
12.11 Kernel access with user permissions ................................................................... 12-29
Chapter 13 Memory Ordering
13.1 Memory types ........................................................................................................ 13-3
