Re: Improve kernelci setup for RISC-V

[Alistair Francis <Alistair.Francis@wdc.com>]

On Thu, 2020-07-02 at 10:12 +0300, David Abdurachmanov wrote:
> Hi,
> 
> I am adding Karsten Merker, Aurelien Jarno and Manuel A. Fernandez
> who
> are working on Debian RISCV.
> 
> Recap: KernelCI uses Debian debootstrap for their test
> infrastructure.
> I believe they are using Buster for it now.
> 
> On Thu, Jul 2, 2020 at 10:02 AM Atish Patra <Atish.Patra@wdc.com>
> wrote:
> > On Wed, 2020-07-01 at 17:17 -0700, Kevin Hilman wrote:
> > > [ + kernelci list ]
> > > 
> > > Hi Atish,
> > > 
> > > Atish Patra <Atish.Patra@wdc.com> writes:
> > > 
> > > > I just want to follow up the discussions we had in the risc-v
> > > > slack
> > > > channel related to improving kernelci setup for RISC-V.
> > > > 
> > > > 1. Adding Qemu target for RISC-V: As per out latest
> > > > conversation,
> > > > this
> > > > won't be an issue anymore as Qemu supports -bios and -kernel
> > > > separately.
> > > 
> > > Yes, this looks straight forward now.  We should be able to get
> > > this
> > > going for our basic tests without too much more work.
> > > 
> > > > 2. Running more tests in addition to boot tests on unleashed
> > > > target:
> > > > 
> > > > The main blocker here is the rootfs. As kernelci only supports
> > > > debian
> > > > based rootfs to actually run tests. I think it is not that
> > > > difficult to
> > > > bootstrap a debian rootfs for RISC-V but I have not done that
> > > > in
> > > > ages.
> > > > I think palmer uses debian rootfs for his testing. I have cc'd
> > > > him
> > > > for
> > > > his inputs.
> > > 
> > > For every other arch, we debootstrap a buster rootfs, and this
> > > doesn't
> > > work for riscv.  But, I just discovered[1] that this should work
> > > for
> > > unstable using debian-ports, so we'll need to update our rootfs
> > > builder
> > > to support unstable/debian-ports.
> > > 
> > > I've cc'd Lakshmipathi from Collabora who has been doing work on
> > > our
> > > rootfs builder tool to see how we can extend this.
> > > 
> > 
> > Thanks.
> > 
> > > > But Alistair & khem (cc'd) expressed interest to add OE to
> > > > kernelci
> > > > as
> > > > well. Can you share some pointers on what needs to be done ?
> > > 
> > > The main tricky/annoying part with yocto is that builds are per-
> > > board,
> > > where as we like to build rootfs images per-arch.  Maybe there's
> > > a
> > > way
> > > to build an arch-generic yocto rootfs using a qemu target or
> > > something,
> > > though.
> > > 
> > > The place to start would be to look at the kci_rootfs tool in the
> > > kernelci-core repo[2] along with the rootfs-config.yaml file and
> > > figure
> > > out how to extend that for yocto/OE.
> > > 
> > > Again, Lakshmipathi may have some ideas there.
> > > 
> > > OTOH, I'm not quite sure what we would gain by using yocto
> > > instead of
> > > debian?  Are there more packages for yocto available than for
> > > debian
> > > currently?
> > > 
> > 
> > TBH, I am not quite sure. I think Khem proposed adding OE support
> > assuming that debian rootfs support may not be possible. If
> > debootstrap
> > can be done from unstable tree, we may not required OE support.
> 
> If we want to test riscv32 you most likely need to go with OE. I
> don't
> think anything else supports RISC-V 32-bit and I don't know if any
> other distro (not targeting embedded market) will work on it.

I think for a RV32 test, OE is probably the best way to go. That should
come after we have a 64-bit test running and upstream support for RV32
in glibc though.

So let's get RV64 up and running first.

Alistair

> 
> I don't know if there will be a Debian riscv32 port.
> 
> Cheers,
> david
> 
> > @Alistair/Khem : Any thoughts ?
> > 
> > > > 3. How difficult is to setup kernelci from scratch locally ?
> > > 
> > > Not really, but it's not well documented. :(
> > > 
> > > But it depends on which parts you want to setup.  There are
> > > several
> > > moving parts:
> > > 
> > > 1) lab / board-farm
> > > 2) backend / storage
> > > 3) frontend
> > > 4) kernel builds (centralized, published publically to
> > >   storage.kernelci.org)
> > > 
> > > We have some rudimentary docs for 2-4 here[3], but the compute
> > > part
> > > for
> > > builds is currently centralized.
> > > 
> > 
> > Thanks for the links. I will go through them.
> > 
> > > Kevin
> > > 
> > > 
> > > [1] https://wiki.debian.org/RISC-V#debootstrap
> > > [2] https://github.com/kernelci/kernelci-core/
> > > [3]
> > > https://github.com/kernelci/kernelci-doc/wiki/Setting-up-a-local-development-instance
> > 
> > --
> > Regards,
> > Atish