zynqmp, ultra96v2: add linux images

[chrisguikema]

This commit adds Petalinux-2021.1 prebuilt images for the zynqmp and ultra96v2 platforms.

[axel-h]

Please provide a README.md in each folder also with a bit if information, e.g. what the images are, where they come from or how to build them. See also the readme file in the other platform folder.

[chrisguikema]

I added a README as seen in other directories. @lsf37 Any insight on how to get the License check to pass?

[lsf37]

@lsf37 Any insight on how to get the License check to pass?

For files that don't allow inline comments, you can add a license and copyright to the .reuse/dep5 file of the same repo. You can also add a filename.license file in the same directory, which would usually be preferred, but in this repo, since there are a bunch of images, I think adding to the dep5 file is nicer.

[chrisguikema]

Thanks, that was really straight forward!

[axel-h]

This PR looks ok now, but what is the merge criterion? There seems a ZCU102 board in CI, having this images now allows activation the VM tests. So passing at least the minimal VM example would be the goal?

[chrisguikema]

See my comment in seL4/camkes-vm#42 for why a minimal example isn't yet feasible.

[chrisguikema]

@lsf37 @kent-mcleod what is the criteria to merge this? These images won't run until the SMC RFC is handled, so is it okay to let this sit? Or would it be better to merge, and then they'll be used in an example in the future?

[kent-mcleod]

@lsf37 @kent-mcleod what is the criteria to merge this? These images won't run until the SMC RFC is handled, so is it okay to let this sit? Or would it be better to merge, and then they'll be used in an example in the future?

Maybe let them sit as they can't break due to other code changes

[chrisguikema]

@kent-mcleod Now that the SMC commits have been reviewed, this could probably be merged. I'll create a PR for a vm_minimal and vm_virtio_net for the zynqmp platform.

[axel-h]

Seems the files in the folders ultra96v2 and zynqmp the same, can't we use just zynqmp here? It seems in seL4/camkes-vm-examples#46 there is no reference to ultra96v2 anyway, so at the moment this is then unused anyway?

[chrisguikema]

Seems the files in the folders ultra96v2 and zynqmp the same

They're different:

chrisguikema: ~/seL4/UPSTREAM/camkes-vm/projects/camkes-vm-images/ultra96v2/2021_1 [zynqmp_ultra96_support] $ md5sum linux rootfs-minimal.cpio.gz 
583ede6e15ce69093fd8800f9d229b8f  linux
a4b5352379915edd286b927d9c55d24e  rootfs-minimal.cpio.gz
chrisguikema: ~/seL4/UPSTREAM/camkes-vm/projects/camkes-vm-images/zynqmp/2021_1 [zynqmp_ultra96_support] $ md5sum linux rootfs-minimal.cpio.gz 
edbad6a15dded2b7e7ffc4aa9e91bfc8  linux
3c46cc201f3a96e007fa090d435b3205  rootfs-minimal.cpio.gz

The big difference with the Ultra96 is that the serial port is on the ff010000 device. There's some files in the rootfs to allow the getty to default to the secondary serial port. But I understand that there isn't an example project for the ultra96 yet, so I can remove those images from this commit.

[axel-h]

Looks ok to me to merge this.

For the Ultra96 (where you removed the files) I am not sure how to handle it. It is a nice board actually, but unfortunately no longer available - so that puts it at a dead end somehow. But there is some support for this platform, so I think we could also merge these images then for more completness?

[chrisguikema]

Yeah, that's unfortunate about the U96. Though i'm sure there are other cheap development platforms that use the ZUS+ processor.

@lsf37 can this be merged?