# QEMU Arm Virt for Standard System Tutorial

## 1. Overview

The `arm_virt/linux` directory contains code that has been verified on the QEMU Arm Virt platform for adapting to Linux kernel. The code includes the driver and board configurations.

The Arm Virt platform is a `qemu-system-arm` target device that simulates a general-purpose board running on the Arm architecture.
The board whose **machine** is **virt** in QEMU is configurable. For example, you can select the core type and quantity, memory size, and security extensions when configuring the board.

This tutorial guides you through the configuration of a board based on the Cortex-A7 architecture, with one CPU, extended secure features, Generic Interrupt Controller versions 2 (GICv2), and 1 GB memory.
The system memory is hardcoded to 1024 MB.

## 2. Setting Up the Environment

For details, see [Environment Setup](https://gitee.com/openharmony/docs/blob/HEAD/en/device-dev/quick-start/quickstart-standard.md)

## 3. Obtaining the Source Code

For details, see [Source Code Acquisition](https://gitee.com/openharmony/docs/blob/HEAD/en/device-dev/get-code/sourcecode-acquire.md).

## 4. Building the Source Code

In the root directory of the obtained source code, run the following command:

```
./build.sh --product-name qemu-arm-linux-min --ccache --jobs 4
```

After this command is executed, the image files for standard system are generated in out/qemu-arm-linux/packages/phone/images/ directory.

## 5. Running an Image in QEMU

a) If `qemu-system-arm` has not been installed, install it. For details, see [Qemu Installation](https://gitee.com/openharmony/device_qemu/blob/HEAD/README.md).

Note: The introduced functions have been tested on the target machine of virt-5.1, but are not available for all QEMU versions. Therefore, you must ensure that the qemu-system-arm version is 5.1 or later.


b) Run the images.

After the source code is built, run the `./vendor/ohemu/qemu_arm_linux_min/qemu_run.sh` command, the images built in step 4 will be started.

c) Exit QEMU.

Press `Ctrl-A + x` to exit the QEMU virtual environment.

# Qemu ARM Virt 标准系统教程

## 1. 简介

`arm_virt/linux` 子目录包含部分Qemu ARM虚拟化平台验证的Linux kernel的适配代码，含驱动配置、板端配置等。

ARM 虚拟化平台是一个 `qemu-system-arm` 的目标设备，通过它来模拟一个通用的、基于ARM架构的单板。
Qemu中machine为 **virt** 的单板就是这种可配置的，例如：选择核的类型、核的个数、内存的大小和安全特性等，单板设备的配置。

这次模拟的配置是：Cortex-A7架构，1个CPU，带安全扩展，GICv2，1G内存。
提示: 系统内存硬编码为1024MB。

## 2. 环境搭建

参考链接: [环境搭建](https://gitee.com/openharmony/docs/blob/HEAD/zh-cn/device-dev/quick-start/quickstart-standard.md)

## 3. 获取源码

参考链接: [代码获取](https://gitee.com/openharmony/docs/blob/HEAD/zh-cn/device-dev/get-code/sourcecode-acquire.md)

## 4. 源码构建

在已经获取的源码根目录，请输入：

```
./build.sh --product-name qemu-arm-linux-min --ccache --jobs 4
```

在构建完成之后，对应的镜像文件在out/qemu-arm-linux/packages/phone/images/目录下。


## 5. 在Qemu中运行镜像

a) 如果没有安装 `qemu-system-arm` ，安装请参考链接 [Qemu installation](https://gitee.com/openharmony/device_qemu/blob/HEAD/README_zh.md)

提示：当前引入的功能在virt-5.1的目标machine已经完成测试，不保证所有的Qemu版本都能够运行成功，因此需要保证你的qemu-system-arm
版本尽可能在5.1及以上。

b) 运行镜像

执行`./vendor/ohemu/qemu_arm_linux_min/qemu_run.sh`即可运行步骤4生成的镜像。

c) 退出qemu环境

按下`Ctrl-A + x`可退出qemu虚拟环境。