The Amlogic Linux 5.15 SDK support for Yocto. We will introduce how to build VIM4 firmware using the Amlogic Linux5.15 SDK here. For readability, the subsequent Amlogic Linux SDK will be referred to as SDK.

Install essential dependencies. It is recommended to use Ubuntu 22.04 for compilation.

sudo apt-get update && sudo apt-get install git ssh make gcc libssl-dev \
liblz4-tool expect expect-dev g++ patchelf chrpath gawk texinfo chrpath \
diffstat binfmt-support qemu-user-static live-build bison flex fakeroot \
cmake gcc-multilib g++-multilib unzip device-tree-compiler ncurses-dev \
libgucharmap-2-90-dev bzip2 expat gpgv2 cpp-aarch64-linux-gnu libgmp-dev \
libmpc-dev bc python-is-python3 python2 libstdc++-12-dev xz-utils repo

1. Download the base SDK packages here: [khadas_vims_yocto_sdk_base.tar.gz* ](https://dl.khadas.com/development/yocto/khadas_vims_yocto_sdk_base)

2. Create and enter the working directory:

 ```
 mkdir ~/project && cd ~/project
 ```

3. Copy khadas_vims_yocto_sdk_base.tar.gz* to ~/project folder

 ```
 cp khadas_vims_yocto_sdk_base.tar.gz* ~/project
 ```

4. Decompress base SDK:

 ```
 cat ~/project/khadas_vims_yocto_sdk_release.tar.gz* | tar -zxv
 ```

5. Then you can see `.repo` derctory in `~/project` directory by using `ls -la` command.

6. Sync and update code:

 ```
 .repo/repo/repo sync -l 
 .repo/repo/repo sync -c
 ```

7. Create a work branch for each repository:

 ```
 .repo/repo/repo start vims_yocto --all
 ```

1.Select Configuration：

kvim1s board: mesons4-kvim1s-5.15

kvim3 board: mesong12b-kvim3-k5.15

kvim3l board: mesongsm1-kvim3l-k5.15

kvim4 board: mesont7c-kvim4-5.15

source meta-meson/aml-setenv.sh
You're building on Linux
Lunch menu...pick a combo:
1.	mesong12b-kvim3-k5.15
2.	mesongsm1-kvim3l-k5.15
3.	mesons4-kvim1s-5.15
4.	mesont7c-kvim4-5.15

Which would you like? [2] 

2.Build:

bitbake amlogic-yocto

3.The constructed image path：

SDK/build/tmp/deploy/images/$Configuration/vimx-yocto-xxxxxx.img

Please refer to: [固件烧录](https://docs.khadas.com/products/sbc/vim4/install-os/install-os-into-emmc-via-usb-tool#tab__vim4)