README.md
1# QEMU(Tutorials of ESP32)
2
3## 1.Introduction
4
5QEMU can simulate the kernel to run on different boards ,eliminate dependence on physical development boards. The esp32 subdirectory contains part of the OpenHarmony kernel\_liteos\_m code verified by the Qemu esp32 virtualization platform, it can be used to simulate a single-core esp32 single board.
6
7## 2.Setup Environment
8
9 1. Install esp-idf
10
11 Please refer to the installation instructions: (https://docs.espressif.com/projects/esp-idf/en/release-v4.1/get-started/index.html)
12
13 Annotation: The installation of esp-idf can be skipped. The bootloader.bin and partition-table.bin generated have been placed in the vendor\ohemu\qemu_xtensa_mini_system_demo\image folder.
14
15 Annotation: If you skip the installation of esp-idf, you can install the toolchain as follows:
16
17 Tip: Users can also skip this step by using the following instructions directly to use the compiler configured in the default environment.
18
19 To use the default environment, execute '3.Get source code' and then install the default compiler in the root directory by executing the following instructions.
20
21 ```shell
22 sh build/prebuilts_download.sh
23 ```
24
25 Optional compiler installation process:
26
27 a) Download the esp official release the SDK package: https://www.espressif.com/zh-hans/support/download/sdks-demos?keys=&field_type_tid%5B%5D=13
28
29 b) Put the downloaded SDK package into the Linux system, go to the directory, and run the following commands:
30
31 ```shell
32 unzip esp-idf-v4.3.1.zip
33 cd esp-idf-v4.3.1/
34 ./install.sh
35 . ./export.sh
36 ```
37
38 c) Delete the default compiler path:
39
40 change esp32\liteos_m\config.gni:
41
42 ```c
43 board_toolchain_path = "$ohos_root_path/prebuilts/gcc/linux-x86/esp/esp-2019r2-8.2.0/xtensa-esp32-elf/bin/"
44 ```
45
46 to
47
48 ```c
49 board_toolchain_path = ""
50 ```
51
52 Annotation: The version of the toolchain used in the test is GCC Version 8.2.0 (Crosstool-ng ESP-2019R2) or GCC Version 8.4.0 (Crosstool-ng ESP-2021R1).
53
54 2. Install esptool
55
56 a) In step 1, the export.sh script will set the esptool in the environment path, you need to ensure that the esptool version is 3.1 and above.
57 ```shell
58 esptool.py version
59 ```
60 b) If the version of the esptool that comes with esp-idf is too low, delete the environment variable corresponding to the current esptool path and run the following commands. (The recommended python version is 3.8 and above)
61 ```shell
62 python -m pip install esptool
63 ```
64
65 3. Compile qemu-system-xtensa
66
67 a) Install and compile
68
69 ```shell
70 git clone https://github.com/espressif/qemu.git
71 cd qemu
72 ./configure --target-list=xtensa-softmmu \
73 --enable-gcrypt \
74 --enable-debug --enable-sanitizers \
75 --disable-strip --disable-user \
76 --disable-capstone --disable-vnc \
77 --disable-sdl --disable-gtk
78 ```
79
80 b) Waitting for the completion of the compilation and executing the installation command (If the compilation fail, please refer to https://github.com/espressif/qemu/issues/21):
81
82 ```shell
83 ninja -C build
84 ```
85
86 c) Add qemu to the environment variable (modify user_qemu_xxx_path to your own installation path)：
87
88 ```shell
89 vim ~/.bashrc
90 export QEMU=user_qemu_xxx_path/qemu/build
91 source ~/.bashrc
92 ```
93
94 d) Installation dependencies
95
96 ```shell
97 ldd $QEMU/qemu-system-xtensa
98 ```
99
100 According to the execution result of ldd, install the missing dependent libraries
101
102 (Annotation: For more installation instructions, please refer to the following link: [Home · espressif/qemu Wiki · GitHub](https://github.com/espressif/qemu/wiki#configure))
103
104## 3.Get source code
105
106[code acquisition ](https://gitee.com/openharmony/docs/blob/master/en/device-dev/get-code/sourcecode-acquire.md)
107
108Hint : You can use the `repo` command to get the source code.
109
110## 4.Source buildding
111
112 1. Execute the hb set command and select the project `qemu_xtensa_mini_system_demo`.
113
114 2. Execute the hb clean && hb build command to build the executable file that produces `OHOS_Image`.
115
116 ```shell
117 hb set
118 hb clean && hb build
119 ```
120
121 3. After the buildding is complete, the corresponding executable file is in the home directory：
122
123 ```
124 out/esp32/qemu_xtensa_mini_system_demo/
125 ```
126
127## 5.Run the image in Qemu
128
129 1. Run qemu(Don't cooperate with GDB )
130
131 ```shell
132 ./qemu-run
133 ```
134
135 2. Run qemu(Cooperate with GDB)
136
137 a) Start the GDB server and wait for the connection
138
139 ```shell
140 ./qemu-run -g
141 ```
142
143 b) Create a new terminal and use GDB to connect to qemu
144
145 ```shell
146 xtensa-esp32-elf-gdb out/esp32/qemu_xtensa_mini_system_demo/OHOS_Image -ex "target remote :1234"
147 ```
148
149 Annotation：Since the qemu-system-xtensa tool of qemu has the same name as the qemu-system-xtensa tool of esp32, the absolute path is used to execute the qemu-system-xtensa tool of esp32.
150 Annotation：The way to exit qemu : press ctrl and a, then release and press x.
151
152(Annotation：For more operating instructions, please refer to：[Home · espressif/qemu Wiki · GitHub](https://github.com/espressif/qemu/wiki#configure))
153