[PATCH] LoongArch: Enable initial Rust support

From: WANG Rui <wangrui@loongson.cn>
To: Miguel Ojeda <ojeda@kernel.org>,
	Alex Gaynor <alex.gaynor@gmail.com>,
	Wedson Almeida Filho <wedsonaf@gmail.com>,
	Huacai Chen <chenhuacai@kernel.org>,
	Jonathan Corbet <corbet@lwn.net>
Cc: "Boqun Feng" <boqun.feng@gmail.com>,
	"Gary Guo" <gary@garyguo.net>,
	"Björn Roy Baron" <bjorn3_gh@protonmail.com>,
	"Benno Lossin" <benno.lossin@proton.me>,
	"Andreas Hindborg" <a.hindborg@samsung.com>,
	"Alice Ryhl" <aliceryhl@google.com>,
	"WANG Xuerui" <kernel@xen0n.name>,
	rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
	loongarch@lists.linux.dev, linux-doc@vger.kernel.org,
	loongson-kernel@lists.loongnix.cn,
	"WANG Rui" <wangrui@loongson.cn>
Subject: [PATCH] LoongArch: Enable initial Rust support
Date: Sat,  6 Jan 2024 14:59:41 +0800	[thread overview]
Message-ID: <20240106065941.180796-1-wangrui@loongson.cn> (raw)

Add initial Rust support for LoongArch.

Signed-off-by: WANG Rui <wangrui@loongson.cn>
---
 Documentation/rust/arch-support.rst |  1 +
 arch/loongarch/Kconfig              |  1 +
 arch/loongarch/Makefile             |  3 +++
 scripts/generate_rust_target.rs     | 10 ++++++++++
 4 files changed, 15 insertions(+)

diff --git a/Documentation/rust/arch-support.rst b/Documentation/rust/arch-support.rst
index b91e9ef4d0c2..e89c8b2efbff 100644
--- a/Documentation/rust/arch-support.rst
+++ b/Documentation/rust/arch-support.rst
@@ -15,6 +15,7 @@ support corresponds to ``S`` values in the ``MAINTAINERS`` file.
 ============  ================  ==============================================
 Architecture  Level of support  Constraints
 ============  ================  ==============================================
+``loongarch`` Maintained
 ``um``        Maintained        ``x86_64`` only.
 ``x86``       Maintained        ``x86_64`` only.
 ============  ================  ==============================================
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 15d05dd2b7f3..6d39ec3077da 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -142,6 +142,7 @@ config LOONGARCH
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_RETHOOK
 	select HAVE_RSEQ
+	select HAVE_RUST
 	select HAVE_SAMPLE_FTRACE_DIRECT
 	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
 	select HAVE_SETUP_PER_CPU_AREA if NUMA
diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile
index 4ba8d67ddb09..ba45cb7b621c 100644
--- a/arch/loongarch/Makefile
+++ b/arch/loongarch/Makefile
@@ -81,8 +81,11 @@ KBUILD_AFLAGS_MODULE		+= -Wa,-mla-global-with-abs
 KBUILD_CFLAGS_MODULE		+= -fplt -Wa,-mla-global-with-abs,-mla-local-with-abs
 endif
 
+KBUILD_RUSTFLAGS_MODULE		+= -Crelocation-model=pic
+
 ifeq ($(CONFIG_RELOCATABLE),y)
 KBUILD_CFLAGS_KERNEL		+= -fPIE
+KBUILD_RUSTFLAGS_KERNEL		+= -Crelocation-model=pie
 LDFLAGS_vmlinux			+= -static -pie --no-dynamic-linker -z notext $(call ld-option, --apply-dynamic-relocs)
 endif
 
diff --git a/scripts/generate_rust_target.rs b/scripts/generate_rust_target.rs
index 3c6cbe2b278d..3edda6a10dd0 100644
--- a/scripts/generate_rust_target.rs
+++ b/scripts/generate_rust_target.rs
@@ -161,6 +161,16 @@ fn main() {
         ts.push("features", features);
         ts.push("llvm-target", "x86_64-linux-gnu");
         ts.push("target-pointer-width", "64");
+    } else if cfg.has("LOONGARCH") {
+        ts.push("arch", "loongarch64");
+        ts.push(
+            "data-layout",
+            "e-m:e-p:64:64-i64:64-i128:128-n64-S128",
+        );
+        ts.push("features", "-f,-d");
+        ts.push("llvm-target", "loongarch64-linux-gnusf");
+        ts.push("llvm-abiname", "lp64s");
+        ts.push("target-pointer-width", "64");
     } else {
         panic!("Unsupported architecture");
     }
-- 
2.43.0

