Re: [RFC PATCH v2 0/5] Implement ARM PL011 in Rust

[Manos Pitsidianakis <manos.pitsidianakis@linaro.org>]

Good morning Daniel,

On Wed, 12 Jun 2024 11:37, "Daniel P. Berrangé" <berrange@redhat.com> wrote:
>On Tue, Jun 11, 2024 at 01:33:29PM +0300, Manos Pitsidianakis wrote:
>
>> 
>>  .gitignore                     |   2 +
>>  .gitlab-ci.d/buildtest.yml     |  64 ++--
>>  MAINTAINERS                    |  13 +
>>  configure                      |  12 +
>>  hw/arm/virt.c                  |   4 +
>>  meson.build                    | 102 ++++++
>>  meson_options.txt              |   4 +
>>  rust/meson.build               |  93 ++++++
>>  rust/pl011/.cargo/config.toml  |   2 +
>>  rust/pl011/.gitignore          |   2 +
>>  rust/pl011/Cargo.lock          | 120 +++++++
>>  rust/pl011/Cargo.toml          |  66 ++++
>>  rust/pl011/README.md           |  42 +++
>>  rust/pl011/build.rs            |  44 +++
>>  rust/pl011/deny.toml           |  57 ++++
>>  rust/pl011/meson.build         |   7 +
>>  rust/pl011/rustfmt.toml        |   1 +
>>  rust/pl011/src/definitions.rs  |  95 ++++++
>>  rust/pl011/src/device.rs       | 531 ++++++++++++++++++++++++++++++
>>  rust/pl011/src/device_class.rs |  95 ++++++
>>  rust/pl011/src/generated.rs    |   5 +
>>  rust/pl011/src/lib.rs          | 581 +++++++++++++++++++++++++++++++++
>>  rust/pl011/src/memory_ops.rs   |  38 +++
>>  rust/rustfmt.toml              |   7 +
>>  rust/wrapper.h                 |  39 +++
>>  scripts/cargo_wrapper.py       | 221 +++++++++++++
>>  scripts/meson-buildoptions.sh  |   6 +
>
>Given the priority of getting the build system correct, what's missing
>here is updates/integration into our standard GitLab CI pipeline. If
>that can be shown to be working, that'll give alot more confidence in
>the overall solution.
>
>Ideally this should not require anything more than updating the docker
>container definitions to add in the rust toolchain, plus the appropriate
>std library build for the given target - we cross compiler for every
>arch we officially care about.
>
>Most of our dockerfiles these days are managed by lcitool, and it has
>nearly sufficient support for cross compiling with the rust std library.
>So to start with, this series should modify tests/lcitool/projects/qemu.yml
>to add
>
>  - rust
>  - rust-std
>
>to the package list, and run 'make lcitool-refresh' to re-create the
>dockerfiles - see the docs/devel/testing.rst for more info about
>lcitool if needed.
>
>Assuming these 2 rust packages are in the container, I would then
>expect QEMU to just "do the right thing" when building this rust
>code. If it does not, then that's a sign of gaps that need closing.
>
>Getting rid of the need to use --rust-target-triple will be the
>immediate gap that needs fixing, as CI just passes --cross-prefix
>for cross-builds and expects everything to be set from that.
>
>The main gap we have is that for Windows I need to update lcitool
>to pull in the mingw std lib target for rust, which I something I
>missed when adding rust cross compiler support.
>


Thanks very much for the pointers! I will start dealing with this in the 
next RFC version.

Re: the target triple, I agree 100%. In fact it wasn't my addition, I 
kept it from the previous rust RFC patchset that was posted on the list 
some years ago. It should be possible to construct the triplets 
ourselves and let the user override if they want to as mentioned in 
another email.

The rust project has official Docker images, do you think it's something 
we could use or is it unnecessary? 

https://github.com/rust-lang/docker-rust

Thanks,
Manos