diff options
| -rw-r--r-- | src/doc/rustc/src/platform-support.md | 7 | ||||
| -rw-r--r-- | src/doc/rustc/src/platform-support/aarch64-unknown-none-hermitkernel.md | 77 |
2 files changed, 81 insertions, 3 deletions
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md index b6ae8c9333f..1cdc1372c21 100644 --- a/src/doc/rustc/src/platform-support.md +++ b/src/doc/rustc/src/platform-support.md @@ -204,7 +204,8 @@ target | std | host | notes `aarch64-apple-tvos` | * | | ARM64 tvOS [`aarch64-kmc-solid_asp3`](platform-support/kmc-solid.md) | ✓ | | ARM64 SOLID with TOPPERS/ASP3 `aarch64-unknown-freebsd` | ✓ | ✓ | ARM64 FreeBSD -`aarch64-unknown-hermit` | ? | | +`aarch64_unknown_hermit` | ✓ | |ARM64 HermitCore +[`aarch64_unknown_none_hermitkernel`](platform-support/aarch64-unknown-none-hermitkernel.md) | * | | ARM64 HermitCore kernel `aarch64-unknown-uefi` | * | | ARM64 UEFI `aarch64-unknown-linux-gnu_ilp32` | ✓ | ✓ | ARM64 Linux (ILP32 ABI) `aarch64-unknown-netbsd` | ✓ | ✓ | @@ -286,10 +287,10 @@ target | std | host | notes `x86_64-sun-solaris` | ? | | Deprecated target for 64-bit Solaris 10/11, illumos `x86_64-unknown-dragonfly` | ✓ | ✓ | 64-bit DragonFlyBSD `x86_64-unknown-haiku` | ✓ | ✓ | 64-bit Haiku -`x86_64-unknown-hermit` | ? | | +`x86_64-unknown-hermit` | ✓ | | HermitCore `x86_64-unknown-l4re-uclibc` | ? | | [`x86_64-unknown-none`](platform-support/x86_64-unknown-none.md) | * | | Freestanding/bare-metal x86_64, softfloat -`x86_64-unknown-none-hermitkernel` | ? | | HermitCore kernel +`x86_64-unknown-none-hermitkernel` | * | | HermitCore kernel `x86_64-unknown-none-linuxkernel` | * | | Linux kernel modules [`x86_64-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 64-bit OpenBSD `x86_64-unknown-uefi` | * | | 64-bit UEFI diff --git a/src/doc/rustc/src/platform-support/aarch64-unknown-none-hermitkernel.md b/src/doc/rustc/src/platform-support/aarch64-unknown-none-hermitkernel.md new file mode 100644 index 00000000000..b8967f63187 --- /dev/null +++ b/src/doc/rustc/src/platform-support/aarch64-unknown-none-hermitkernel.md @@ -0,0 +1,77 @@ +# `aarch64-unknown-none-hermitkernel` + +**Tier: 3** + +Required to build the kernel for [HermitCore](https://github.com/hermitcore/hermit-playground) +or [RustyHermit](https://github.com/hermitcore/rusty-hermit). +The result is a bare-metal aarch64 binary in ELF format. + +## Target maintainers + +- Stefan Lankes, https://github.com/stlankes + +## Requirements + +This target is cross-compiled. There is no support for `std`, but the +library operating system provides a simple allocator to use `alloc`. + +By default, Rust code generated for this target does not use any vector or +floating-point registers. This allows the generated code to build the library +operaring system, which may need to avoid the use of such +registers or which may have special considerations about the use of such +registers (e.g. saving and restoring them to avoid breaking userspace code +using the same registers). In contrast to `aarch64-unknown-none-softfloat`, +the target is completly relocatable, which is a required feature of RustyHermit. + +By default, code generated with this target should run on any `aarch64` +hardware; enabling additional target features may raise this baseline. +On `aarch64-unknown-none-hermitkernel`, `extern "C"` uses the [standard System V calling +convention](https://github.com/ARM-software/abi-aa/releases/download/2021Q3/sysvabi64.pdf), +without red zones. + +This target generated binaries in the ELF format. + +## Building the target + +Typical you should not use the target directly. The target `aarch64-unknown-hermit` +builds the _user space_ of RustyHermit and supports red zones and floating-point +operations. +To build and link the kernel to the application, the crate +[hermit-sys](https://github.com/hermitcore/rusty-hermit/tree/master/hermit-sys) +should be used by adding the following lines to the `Cargo.toml` file of +your application. + +```toml +[target.'cfg(target_os = "hermit")'.dependencies] +hermit-sys = "0.1.*" +``` + +The crate `hermit-sys` uses the target `aarch64-unknown-none-hermitkernel` +to build the kernel. + +## Building Rust programs + +Rust does not yet ship pre-compiled artifacts for this target. To compile for +this target, you need to build the crate `hermit-sys` (see +"Building the target" above). + +## Testing + +As `aarch64-unknown-none-hermitkernel` does not support `std` +and does not support running any Rust testsuite. + +## Cross-compilation toolchains and C code + +If you want to compile C code along with Rust you will need an +appropriate `aarch64` toolchain. + +Rust *may* be able to use an `aarch64-linux-gnu-` toolchain with appropriate +standalone flags to build for this toolchain (depending on the assumptions of +that toolchain, see below), or you may wish to use a separate +`aarch64-unknown-none` (or `aarch64-elf-`) toolchain. + +On some `aarch64` hosts that use ELF binaries, you *may* be able to use the host +C toolchain, if it does not introduce assumptions about the host environment +that don't match the expectations of a standalone environment. Otherwise, you +may need a separate toolchain for standalone/freestanding development, just as +when cross-compiling from a non-`aarch64` platform. |