NOTE!!
======

Since the tools are going to access real hardware registers and may result in
unexpected behaviors, it is absolutely not allowed to be used in production
environment, but ONLY for TEST and DEBUG.

system-register-tools Build
===========================

		0. install MSR-ARM module
		1. make & make install system-register-tools

Introduction
============

system-register-tools is aiming to access the system registers for arm64
platform. It was designed by SMC (self-modify code) method to read or write
date to registers. We use this tool to replace x86 MSR-tools, and depends on
MSR-ARM module on use.

In addition, we make the usage of system-register-tools similar to MSR-tools.
For engineers familiar with MSR-tools, they can quickly install and use this
tool.

HOW-TO
======

Firstly, the system should make sure have installed the MSR-ARM module.

Next, MSR-ARM module is already installed, install system-register-tools as
follows:

		make && make install

To run this program, like follows:

		rdasr -p0 -r MPIDR_EL1

The log here:

register: MPIDR_EL1
0x80000000

For another core, likes: rdasr -p<core> -r MPIDR_EL1

In addition, writing to registers likes:

		wrasr -p0 -r <register name> <write data>

MSR TEST
========

The script in scripts/ directory is mainly used to start multiple threads to
read registers.

In addition, there is a test for all system registers:

		rdasr -t

The log here:

 0: OSDTRRX_EL1         : UNDEFINED or unreadable!
 1: DBGBVR0_EL1         : 0x0
 2: DBGBCR0_EL1         : 0x1e0
 3: DBGWVR0_EL1         : 0x0
 4: DBGWCR0_EL1         : 0x0
 5: DBGBVR1_EL1         : 0x0
 6: DBGBCR1_EL1         : 0x1e0
 7: DBGWVR1_EL1         : 0x0
 8: DBGWCR1_EL1         : 0x0
 9: MDCCINT_EL1         : 0x0
10: MDSCR_EL1           : 0x1000
11: DBGBVR2_EL1         : 0x0
...
598: ICC_IGRPEN1_EL3     : UNDEFINED or unreadable!
599: TPIDR_EL3           : UNDEFINED or unreadable!
600: SCXTNUM_EL3         : UNDEFINED or unreadable!
601: CNTPS_TVAL_EL1      : UNDEFINED or unreadable!
602: CNTPS_CTL_EL1       : UNDEFINED or unreadable!
603: CNTPS_CVAL_EL1      : UNDEFINED or unreadable!
604: CNTPS_CVAL_EL1      : UNDEFINED or unreadable!

The test ended and no system exception occurred!
Undefined or unreadable registers: 409
Readable registers: 196

Contribution
============

0. Read docs/coding_style.txt in docs/

1. Do NOT use master/dev branch for development directly:

   a. Checkout your branch from dev
   b. Doing something...
   c. Submit ONLY merge request to dev branch
   d. After reviewed by maintainers, the patch(es) will be merged into dev
   e. Only merge dev into master branch when releasing a formal version

Contributors
============

Rongwei Wang, Cao Zou, Zhuo Song