[Caml-list] Status of the OCaml RISC-V port

[Caml-list] Status of the OCaml RISC-V port

[Richard W.M. Jones]

Fedora has been maintaining an out of tree RISC-V patch in our OCaml
package for about 18 months, from:

  https://github.com/nojb/riscv-ocaml/commits/trunk

This has proven to be fairly stable, and I'm wondering when / under
what conditions it can go upstream?

RISC-V finally settled on a stable libc ABI (contributed to glibc
2.27) which has allowed us to start porting Fedora to RISC-V for real.
You can grab bootable disk images from:

  https://fedorapeople.org/groups/risc-v/disk-images/

and inside run 'dnf install ocaml' which will currently install
OCaml 4.06.0 with native RISC-V support.  There is also sshd,
systemd, gcc, etc., albeit lacking emacs :-(

At the moment you can run these on an out of tree qemu patch:

  https://github.com/riscv/riscv-qemu/tree/qemu-upstream-v6

which supports multiple virtual CPUs and (if you have fast enough
hardware) is fairly reasonable for development.

There are also development boards coming but it's likely you'll have
to wait til July for general availability and even then they will cost
$1000 and are not expected to have very good performance.  I notice
that avsm has signed up for one.

Rich.

Re: [Caml-list] Status of the OCaml RISC-V port

[SP]

On Sun, Feb 25, 2018 at 04:14:30PM +0000, Richard W.M. Jones wrote:
>Fedora has been maintaining an out of tree RISC-V patch in our OCaml
>package for about 18 months, from:
>
>  https://github.com/nojb/riscv-ocaml/commits/trunk

Is it possible to get with opam switch?

>There are also development boards coming but it's likely you'll have
>to wait til July for general availability and even then they will cost
>$1000 and are not expected to have very good performance.

I've been looking at this from the periphery, for 1k is a tall bill just
for messing around. What's the forecast for something more affordable
and usable?

-- 
	SP

Re: [Caml-list] Status of the OCaml RISC-V port

[Richard W.M. Jones]

On Sun, Feb 25, 2018 at 04:30:08PM +0000, SP wrote:
> On Sun, Feb 25, 2018 at 04:14:30PM +0000, Richard W.M. Jones wrote:
> > Fedora has been maintaining an out of tree RISC-V patch in our OCaml
> > package for about 18 months, from:
> > 
> >  https://github.com/nojb/riscv-ocaml/commits/trunk
> 
> Is it possible to get with opam switch?

Do you mean on an x86_64 host?  Given that I haven't finished
compiling all the deps for opam it definitely won't work in the Fedora
RISC-V image.  In any case we're developing a distribution, so my
primary concern is with the Fedora OCaml package.

> > There are also development boards coming but it's likely you'll have
> > to wait til July for general availability and even then they will cost
> > $1000 and are not expected to have very good performance.
> 
> I've been looking at this from the periphery, for 1k is a tall bill just
> for messing around. What's the forecast for something more affordable
> and usable?

Eventually, but not likely this year.

Rich.

RE: [Caml-list] Status of the OCaml RISC-V port

[David Allsopp]

Richard W.M. Jones wrote:
> Fedora has been maintaining an out of tree RISC-V patch in our OCaml
> package for about 18 months, from:
> 
>   https://github.com/nojb/riscv-ocaml/commits/trunk
> 
> This has proven to be fairly stable, and I'm wondering when / under what
> conditions it can go upstream?

Primary concern has been access to real hardware (Xavier has reasonable issues with maintaining via Qemu only), especially given that OCaml's cross-compilation support is not strong (enough).

<snip>

> There are also development boards coming but it's likely you'll have to
> wait til July for general availability and even then they will cost
> $1000 and are not expected to have very good performance.  I notice that
> avsm has signed up for one.

We do indeed have a development board coming to Cambridge, and this will hopefully start the process of upstreaming the RISC-V patches. Given timings, it clearly won't be part of OCaml 4.07 though there is a possibility the infrastructure could be in place to allow it to be in OCaml 4.08.


David

RE: [Caml-list] Status of the OCaml RISC-V port

[SP]

On 25 February 2018 19:29:45 GMT+00:00, David Allsopp <dra-news@metastack.com> wrote:
>will hopefully start the process of upstreaming the RISC-V patches.

Will you be looking for help from the wider community for this?

-- 
    SP

Re: [Caml-list] Status of the OCaml RISC-V port

[Nicolás Ojeda Bär]

[-- Attachment #1: Type: text/plain, Size: 655 bytes --]

Hello,

As a general rule, help from the community is always welcome :)

When the time comes, the patch will be submitted as a github PR and
everyone is warmly invited to take part in that discussion.

And of course, PRs are also welcome anytime at
https://github.com/nojb/riscv-ocaml !

Best wishes,
Nicolás


On Sun, Feb 25, 2018 at 10:35 PM, SP <sp@orbitalfox.eu> wrote:

>
>
> On 25 February 2018 19:29:45 GMT+00:00, David Allsopp <
> dra-news@metastack.com> wrote:
> >will hopefully start the process of upstreaming the RISC-V patches.
>
> Will you be looking for help from the wider community for this?
>
> --
>     SP
>

[-- Attachment #2: Type: text/html, Size: 1231 bytes --]

Re: [Caml-list] Status of the OCaml RISC-V port

[Xavier Leroy]

[-- Attachment #1: Type: text/plain, Size: 1144 bytes --]

On Sun, Feb 25, 2018 at 11:36 PM Nicolás Ojeda Bär <
nicolas.ojeda.bar@lexifi.com> wrote:

>
> When the time comes, the patch will be submitted as a github PR and
> everyone is warmly invited to take part in that discussion.
>
>
Absolutely.  Just to reinforce what's been said already: there is no doubt
in my mind that the RISC-V back-end will be part of the core OCaml
distribution.  What is not completely decided is when it will be merged.
I'm looking forward to playing with the first RISC-V hardware
implementation, thanks to OCaml Labs.  It's good to know about the
QEMU-based virtual environment mentioned by Rich Jones.

- Xavier Leroy


> And of course, PRs are also welcome anytime at
> https://github.com/nojb/riscv-ocaml !
>
> Best wishes,
> Nicolás
>
>
> On Sun, Feb 25, 2018 at 10:35 PM, SP <sp@orbitalfox.eu> wrote:
>
>>
>>
>> On 25 February 2018 19:29:45 GMT+00:00, David Allsopp <
>> dra-news@metastack.com> wrote:
>> >will hopefully start the process of upstreaming the RISC-V patches.
>>
>> Will you be looking for help from the wider community for this?
>>
>> --
>>     SP
>>
>
>

[-- Attachment #2: Type: text/html, Size: 2176 bytes --]

Re: [Caml-list] Status of the OCaml RISC-V port

[SP]

On Sun, Feb 25, 2018 at 11:35:25PM +0100, Nicolás Ojeda Bär wrote:
> When the time comes, the patch will be submitted as a github PR and
> everyone is warmly invited to take part in that discussion.

Is the development discussion taking place on some other discussion
list?

-- 
	SP

Re: [Caml-list] Status of the OCaml RISC-V port

[Richard W.M. Jones]

On Mon, Feb 26, 2018 at 02:13:21PM +0000, SP wrote:
> On Sun, Feb 25, 2018 at 11:35:25PM +0100, Nicolás Ojeda Bär wrote:
> > When the time comes, the patch will be submitted as a github PR and
> > everyone is warmly invited to take part in that discussion.
> 
> Is the development discussion taking place on some other discussion
> list?

TBH there's not been much discussion at all because it has
largely just worked for the past 18 months.

Rich.