Mention how to include initramfs when building the kernel

Signed-off-by: Ann Yun <by.ann.yun@gmail.com>
---
 Documentation/arch/openrisc/openrisc_port.rst | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/arch/openrisc/openrisc_port.rst b/Documentation/arch/openrisc/openrisc_port.rst
index a8f307a3b499..4ab28879d7ed 100644
--- a/Documentation/arch/openrisc/openrisc_port.rst
+++ b/Documentation/arch/openrisc/openrisc_port.rst
@@ -40,6 +40,10 @@ Build the Linux kernel as usual::
 	make ARCH=openrisc CROSS_COMPILE="or1k-linux-" defconfig
 	make ARCH=openrisc CROSS_COMPILE="or1k-linux-"
 
+If you want to embed initramfs in the kernel, also pass ``CONFIG_INITRAMFS_SOURCE``. For example::
+
+	make ARCH=openrisc CROSS_COMPILE="or1k-linux-" CONFIG_INITRAMFS_SOURCE="path/to/rootfs path/to/devnodes"
+
 3) Running on FPGA (optional)
 
 The OpenRISC community typically uses FuseSoC to manage building and programming
-- 
2.37.2

On Fri, Apr 25, 2025 at 04:10:18PM -0400, Ann Yun wrote:
> Mention how to include initramfs when building the kernel
> 
> Signed-off-by: Ann Yun <by.ann.yun@gmail.com>
> ---
>  Documentation/arch/openrisc/openrisc_port.rst | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/Documentation/arch/openrisc/openrisc_port.rst b/Documentation/arch/openrisc/openrisc_port.rst
> index a8f307a3b499..4ab28879d7ed 100644
> --- a/Documentation/arch/openrisc/openrisc_port.rst
> +++ b/Documentation/arch/openrisc/openrisc_port.rst
> @@ -40,6 +40,10 @@ Build the Linux kernel as usual::
>  	make ARCH=openrisc CROSS_COMPILE="or1k-linux-" defconfig
>  	make ARCH=openrisc CROSS_COMPILE="or1k-linux-"
>  
> +If you want to embed initramfs in the kernel, also pass ``CONFIG_INITRAMFS_SOURCE``. For example::
> +
> +	make ARCH=openrisc CROSS_COMPILE="or1k-linux-" CONFIG_INITRAMFS_SOURCE="path/to/rootfs path/to/devnodes"
> +

I think this is good, but maybe we can mention to refer to Documentation/filesystems/ramfs-rootfs-initramfs.rst
for more details on this?

Also, it may be helpful to mention we can get pre-built busybox rootfs images
here:

  https://github.com/stffrdhrn/or1k-rootfs-build/releases

But if we do that then it would be better to show how to use thos rootfs images,
which maybe something better we have in our openrisc/tutorials[0].

-Stafford

[0] https://github.com/openrisc/tutorials

>  3) Running on FPGA (optional)
>  
>  The OpenRISC community typically uses FuseSoC to manage building and programming
> -- 
> 2.37.2
>

Hi Stafford,

I am sending my same reply to the whole group again, because I
previously did not do "Reply All".

On Sat, Apr 26, 2025 at 4:50 AM Stafford Horne <shorne@gmail.com> wrote:
>
> I think this is good, but maybe we can mention to refer to Documentation/filesystems/ramfs-rootfs-initramfs.rst
> for more details on this?

Thanks for pointing that out. That is an excellent idea, I will add that.

> Also, it may be helpful to mention we can get pre-built busybox rootfs images
> here:
>
>   https://github.com/stffrdhrn/or1k-rootfs-build/releases
>
> But if we do that then it would be better to show how to use thos rootfs images,
> which maybe something better we have in our openrisc/tutorials[0].
>
> -Stafford
>
> [0] https://github.com/openrisc/tutorials

Exactly! I was working on a QEMU tutorial inside openrisc/tutorials
and that prompted me to add that one line here.

Ann