add main branch files

website/docs/guide/how-to-build.md

@@ -0,0 +1,71 @@
+# How to build
+
+First, you should read the official Android documentation for kernel build:
+
+1. [Build kernels](https://source.android.com/docs/setup/build/building-kernels)
+2. [GKI release builds](https://source.android.com/docs/core/architecture/kernel/gki-release-builds)
+
+::: warning
+This page is for GKI devices, if you use an old kernel, please refer [Intergrate for non-GKI devices](how-to-integrate-for-non-gki).
+:::
+
+## Build kernel
+
+### Sync the kernel source code
+
+```sh
+repo init -u https://android.googlesource.com/kernel/manifest
+mv <kernel_manifest.xml> .repo/manifests
+repo init -m manifest.xml
+repo sync
+```
+
+The `<kernel_manifest.xml>` file is a manifest that uniquely identifies a build, allowing you to make it reproducible. To do this, you should download the manifest file from [GKI release builds](https://source.android.com/docs/core/architecture/kernel/gki-release-builds).
+
+### Build
+
+Please check the [Building kernels](https://source.android.com/docs/setup/build/building-kernels) first.
+
+For example, to build an `aarch64` kernel image:
+
+```sh
+LTO=thin BUILD_CONFIG=common/build.config.gki.aarch64 build/build.sh
+```
+
+Don't forget to add the `LTO=thin` flag; otherwise, the build may fail if your computer has less than 24 GB of memory.
+
+Starting from Android 13, the kernel is built by `bazel`:
+
+```sh
+tools/bazel build --config=fast //common:kernel_aarch64_dist
+```
+
+::: info
+For some Android 14 kernels, to make Wi-Fi/Bluetooth work, it might be necessary to remove all GKI protected exports:
+
+```sh
+rm common/android/abi_gki_protected_exports_*
+```
+:::
+
+## Build kernel with KernelSU
+
+If you can successfully build the kernel, adding support for KernelSU will be relatively easy. In the root of kernel source directory, run any of the options listed below:
+
+::: code-group
+
+```sh[Latest tag (stable)]
+curl -LSs "https://raw.githubusercontent.com/tiann/KernelSU/main/kernel/setup.sh" | bash -
+```
+
+```sh[ main branch (dev)]
+curl -LSs "https://raw.githubusercontent.com/tiann/KernelSU/main/kernel/setup.sh" | bash -s main
+```
+
+```sh[Select tag (such as v0.5.2)]
+curl -LSs "https://raw.githubusercontent.com/tiann/KernelSU/main/kernel/setup.sh" | bash -s v0.5.2
+```
+
+:::
+
+Then, rebuild the kernel and you will get a kernel image with KernelSU!