Re: [PATCH v2 3/3] Add custom isar-initramfs example

[Jan Kiszka <jan.kiszka@siemens.com>]

On 25.09.20 13:28, Harald Seiler wrote:
> On Fri, 2020-09-25 at 11:13 +0200, Jan Kiszka wrote:
>> On 23.09.20 18:20, Harald Seiler wrote:
>>> isar-initramfs is a custom initramfs which additionally has the
>>> initramfs-example module installed.
>>>
>>> Signed-off-by: Harald Seiler <hws@denx.de>
>>> ---
>>>
>>> Notes:
>>>      Maybe this initramfs should be tested in CI somewhere?  I'm unsure what
>>>      makes sense, and how to "force" this custom initramfs into a CI target.
>>>
>>>   .../recipes-initramfs/images/isar-initramfs.bb | 18 ++++++++++++++++++
>>>   1 file changed, 18 insertions(+)
>>>   create mode 100644 meta-isar/recipes-initramfs/images/isar-initramfs.bb
>>>
>>> diff --git a/meta-isar/recipes-initramfs/images/isar-initramfs.bb b/meta-isar/recipes-initramfs/images/isar-initramfs.bb
>>> new file mode 100644
>>> index 000000000000..aaa0350aab20
>>> --- /dev/null
>>> +++ b/meta-isar/recipes-initramfs/images/isar-initramfs.bb
>>> @@ -0,0 +1,18 @@
>>> +# Example of a custom initramfs image recipe.  The image will be deployed to
>>> +#
>>> +#   build/tmp/deploy/images/${MACHINE}/isar-initramfs-${DISTRO}-${MACHINE}.initrd.img
>>> +#
>>> +# This software is a part of ISAR.
>>> +
>>> +inherit initramfs
>>> +
>>> +# Debian packages that should be installed into the system for building the
>>> +# initramfs.  E.g. the cryptsetup package which contains initramfs scripts for
>>> +# decrypting a root filesystem.
>>> +INITRAMFS_PREINSTALL += " \
>>> +    "
>>> +
>>> +# Recipes that should be installed into the initramfs build rootfs.
>>> +INITRAMFS_INSTALL += " \
>>> +    initramfs-example \
>>> +    "
>>>
>>
>> If this recipe is not pulled somewhere, it's dead.
> 
> Right, that's why I was asking where to put it.
> 
>> Some test-only dependencies we had to local.conf in scripts/ci_build.sh.
>> Or you add it to meta-isar/conf/local.conf.sample.
>>
>> If added, will it simply replace the default initramfs? Or is more needed?
> 
> Well, there really isn't such a thing as the default initramfs right now.
> `image.bbclass` deploys its own initramfs (the one debian installed to
> /boot) to `${IMAGE_FULLNAME}-initrd.img` which further tasks could then
> reference when building e.g. a fitImage or it could be added to
> IMAGE_BOOT_FILES for WIC.
> 
> Similarly, the new `initramfs.bbclass` deploys the final artifact to
> `${INITRAMFS_FULLNAME}.initrd.img`.  What happens after that is entirely
> up to the integrator.  After all, this image-class is meant for cases
> where customization beyond the abilities of the current in-rootfs
> initramfs are needed.  As an example, a fitImage recipe could use this
> like
> 
>     INITRAMFS_RECIPE = "isar-initramfs"
> 
>     INITRD_IMG = "${PP_DEPLOY}/${INITRAMFS_RECIPE}-${DISTRO}-${MACHINE}.initrd.img"
>     do_fit_image[depends] += "${INITRAMFS_RECIPE}:do_build"
> 
> ---
> 
> Now, for CI if we want to include this custom initramfs, we'd need to
> either modify some image recipe to pull it in as shown above or build it
> separately and then start qemu with
> 
>     -initrd build/tmp/deploy/images/qemuamd64/isar-initramfs-debian-buster-qemuamd64.initrd.img
> 
> somewhere.  But I'm not sure if that's easily integrated into the current
> setup?
> 
> IMO the next best thing would be to just build test it.  Would adding
> 
>     mc:qemuamd64-buster:isar-initramfs
> 
> to TARGETS_SET in ci_build.sh work?
> 

We already have fit/ubi example. Could that be expanded better to stress
this? Otherwise, I'm find with your suggestion above.

Jan

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