add experimental support for android platform images

[Alexander Sack]

partition layout would be
 + boot (vfat) - 128M - not mounted
 + rootfs (ext4) - 128M - mounted: /
 + system (ext4) - 256M - mounted /system
 + cache (ext4) - 256M - mounted /cache
 + userdata (ext4) - 512M - mounted /data
 + sdcard (ext4) - rest of size - mounted as /sdcard

artifacts for userspace from here https://android-build.linaro.org/jenkins/job/linaro-android_beagle/
 + after mounting the partitions like above, just unpack all tarballs (system, root, userdata) to /

also we said we will have an experimental hwpack tarball thing for now that would have two main directories:

 + boot/
 + overlay/

 * with boot/ being what needs to go on the boot partition (e.g. u-boot.bin, uImage)
 * and overlay/ being a tree structure that you have to copy to / after combining the other tarballs from above.

[James Westby (james-w)]

Hi,

salgado estimates that putting together a linaro-android-media-create prototype that

  * Partitions the image in that layout
  * Installs the artefacts
  * Writes it to an SD card

will be about a days work.

It's not clear how you want to generate the hwpacks at this stage.

Installing them as you describe should be straightforward, but we can't estimate anything
about their creation without knowing more about your thoughts there.

Thanks,

James

[Alexander Sack (asac)]

I think creation of hwpacks is out of scoped for this bug.

We dont even know yet how we will create the kernel etc.

Most likely we will have something that uses manifest mechanism to branch a source tree - including kernel - and then builds it and produces the tarball described. That thing should then be easy to deploy in linaro clouds build service I would hope.

[Alexander Sack (asac)]

in other words: atm i dont see us requiring support for android hwpack creation in l-i-t.
... but as you know things might change ;)

[Scott Bambrough (scottb)]

If I remember correctly, Android in general generates 3 artefacts, a rootfs, data fs, kernel, and for some targets possibly some bootloader bits. The rootfs will contain all the hardware related bits. I know we use HWPACK's to separate out hardware bits from our Linux rootfs, but this is not a good idea for Android if we want to achieve Linaro's goals regarding Android. I would not deviate from the expected Android workflow to allow us to gain some traction with Google. The closer we are to stock Android workflow, the easier it is for Google to look at what we have done, without a lot of education on our part.

[James Westby (james-w)]

On Fri, 25 Feb 2011 12:26:05 -0000, Alexander Sack <email address hidden> wrote:
> I think creation of hwpacks is out of scoped for this bug.
>
> We dont even know yet how we will create the kernel etc.
>
> Most likely we will have something that uses manifest mechanism to
> branch a source tree - including kernel - and then builds it and
> produces the tarball described. That thing should then be easy to deploy
> in linaro clouds build service I would hope.

Ok. Do we want to have the code to install hwpacks in the first
iteration, or just the partitioning and installation of the three
artefacts?

Thanks,

James

[Scott Bambrough (scottb)]

You don't want hardware packs at all for Android. If you want to build a tool, it should take the kernel, and the files generated for the target in the Android source tree, and install them properly. What is created and required to make things work is target dependent. You might want to examine the output for number of targets first before creating this tool.

[Jeremy Chang (jeremychang)]

I created a branch, lp:~jeremychang/linaro-image-tools/android,

Right now it can just do as the following command does:
$ sudo ./linaro-android-media-create --dev beagle --system system.tar.bz2 --userdata userdata.tar.bz2 --root root.tar.bz2 --mmc /dev/sdb

boot partition is not considered and deployed yet.

[Alexander Sack (asac)]

------------------------------------------------------------
revno: 312 [merge]
committer: Alexander Sack <email address hidden>
branch nick: linaro-image-tools
timestamp: Tue 2011-04-05 11:26:47 +0200
message:
  Merge lp:~jeremychang/linaro-image-tools/android adding experimental linaro
  android platform image support; LP: #724207
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