[PATCH v2 8/8] Documentation: add howto build in macos

[Daniel Gomez (Samsung)]

On Sat, Sep 7, 2024 at 10:33 AM Masahiro Yamada <masahiroy at kernel.org> wrote:
>
> On Fri, Sep 6, 2024 at 8:01 PM Daniel Gomez via B4 Relay
> <devnull+da.gomez.samsung.com at kernel.org> wrote:
> >
> > From: Daniel Gomez <da.gomez at samsung.com>
> >
> > Add documentation under kbuild/llvm to inform about the experimental
> > support for building the Linux kernel in macOS hosts environments.
> >
> > Signed-off-by: Daniel Gomez <da.gomez at samsung.com>
>
>
> Instead, you can add this instruction to:
>
> https://github.com/bee-headers/homebrew-bee-headers/blob/main/README.md

Sure, that can be done as well. But the effort here is to have this
integrated. So, I think documentation should be in-tree.

>
>
>
>
>
> > ---
> >  Documentation/kbuild/llvm.rst | 78 +++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 78 insertions(+)
> >
> > diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst
> > index 6dc66b4f31a7..de3bde925793 100644
> > --- a/Documentation/kbuild/llvm.rst
> > +++ b/Documentation/kbuild/llvm.rst
> > @@ -186,6 +186,84 @@ yet. Bug reports are always welcome at the issue tracker below!
> >       - Supported
> >       - ``LLVM=1``
> >
> > +Experimental Build in macOS
> > +---------------------------
> > +
> > +Building on macOS with LLVM is experimental. This section provides steps to
> > +install dependencies via Homebrew, set up the environment, and start the build
> > +process.
> > +
> > +1. **Create a Case-Sensitive Volume**
> > +
> > +   For fetching and building the project, you need a case-sensitive volume. Use the following
> > +   command to create one:
> > +
> > +   .. code-block:: shell
> > +
> > +      diskutil apfs addVolume /dev/disk<N> "Case-sensitive APFS" linux
> > +
> > +   Replace `/dev/disk<N>` with the appropriate disk identifier.
> > +
> > +2. **Install Build Dependencies**
> > +
> > +Use Homebrew to install the required build dependencies.
> > +
> > +- **Core Utilities**: `coreutils`, `findutils`, `gnu-sed`, `gnu-tar`, `grep`,
> > +  `llvm`, `make`, and `pkg-config`.
> > +
> > +   .. code-block:: shell
> > +
> > +      brew install coreutils findutils gnu-sed gnu-tar grep llvm make pkg-config
> > +
> > +- **Bee Headers**: Install byteswap, elf and endian headers using the
> > +  `Bee Headers Project <https://github.com/bee-headers/headers>`_.
> > +
> > +   .. code-block:: shell
> > +
> > +      brew tap bee-headers/bee-headers
> > +      brew install bee-headers/bee-headers/bee-headers
> > +
> > +   After installation, verify the `CFLAGS` with `pkg-config`:
> > +
> > +   .. code-block:: shell
> > +
> > +      pkg-config --cflags bee-headers
> > +      -I/opt/homebrew/Cellar/bee-headers/0.1/include
> > +
> > +3. **Configure the PATH**
> > +
> > +   Include all the required GNU tools and LLVM in your `PATH`. This ensures that
> > +   the necessary tools are available during the build process.
> > +
> > +   .. code-block:: shell
> > +
> > +      PATH="/opt/homebrew/opt/coreutils/libexec/gnubin:$PATH"
> > +      PATH="/opt/homebrew/opt/findutils/libexec/gnubin:$PATH"
> > +      PATH="/opt/homebrew/opt/gnu-sed/libexec/gnubin:$PATH"
> > +      PATH="/opt/homebrew/opt/gnu-tar/libexec/gnubin:$PATH"
> > +      PATH="/opt/homebrew/opt/grep/libexec/gnubin:$PATH"
> > +      PATH="/opt/homebrew/opt/make/libexec/gnubin:$PATH"
> > +      PATH="/opt/homebrew/opt/llvm/bin:$PATH"
> > +
> > +Building the Project
> > +--------------------
> > +
> > +Once the environment is set up, you can start the build process using LLVM. Run
> > +the following commands to initiate the build:
> > +
> > +.. code-block:: shell
> > +
> > +   make LLVM=1 allyesconfig
> > +   make LLVM=1 -j$(nproc)
> > +
> > +Supported in macOS
> > +~~~~~~~~~~~~~~~~~~
> > +
> > +At the moment, only arm64 is supported and tested with `allyesconfig` Makefile
> > +configuration target. Other Kconfig options not included in `allyesconfig`
> > +target and architectures may be supported as well as support in macOS is based
> > +on LLVM effort and maintenance.
> > +
> >  Getting Help
> >  ------------
> >
> >
> > --
> > 2.46.0
> >
> >
>
>
> --
> Best Regards
> Masahiro Yamada