From nobody Sun Feb 8 19:30:22 2026 Received: from luna.linkmauve.fr (luna.linkmauve.fr [82.65.109.163]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1D76F23D7DC; Wed, 4 Feb 2026 03:05:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.65.109.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770174332; cv=none; b=ahmYOf3vxDxsQULwVznz9mOXprl+C2WTFm7ZHx07nMI3ToPvhEBO1Mxp9CvPLdYlz6WGq1b2ct2qgmKt07FRiHjtLmwqepLLNTw7GqnZUZnA/qGkZp5ERcD1QvcDo22f1xpBnPtsCyKfzSyMhINIjkeHipyBnoEAoIw7X9ruDQk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770174332; c=relaxed/simple; bh=cgCjVwbypryUVqc9Sw/brcR+Z7pSXhymG5eJERS31LM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=cP7RUTrF/H+7pGvwOxZ1lqTgzi1DUteN5/4febRLFSNMV/+S7CJkF6fgrPe6OEGTkCfFBvtZa90ysYog+7m51gVtOiAmaUqJCbemqJm7nOtuV/rTQCqosM0oq4EjP3znek6RyVgNVwOvFrpM7dRdV7FfFG4Pl+JVFHSc64Ahm/0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linkmauve.fr; spf=pass smtp.mailfrom=linkmauve.fr; arc=none smtp.client-ip=82.65.109.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linkmauve.fr Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linkmauve.fr Received: by luna.linkmauve.fr (Postfix, from userid 1000) id 081FBF43B32; Wed, 04 Feb 2026 04:05:19 +0100 (CET) From: Link Mauve To: rust-for-linux@vger.kernel.org Cc: Link Mauve , Miguel Ojeda , Boqun Feng , Gary Guo , =?UTF-8?q?Bj=C3=B6rn=20Roy=20Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich , Jonathan Corbet , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Peter Zijlstra , Josh Poimboeuf , Jason Baron , Steven Rostedt , Ard Biesheuvel , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, llvm@lists.linux.dev, officialTechflashYT@gmail.com, Ash Logan , Roberto Van Eeden , =?UTF-8?q?Jonathan=20Neusch=C3=A4fer?= Subject: [PATCH] rust: Add PowerPC support Date: Wed, 4 Feb 2026 04:05:04 +0100 Message-ID: <20260204030507.8203-1-linkmauve@linkmauve.fr> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable For now only Big Endian 32-bit PowerPC is supported, as that is the only hardware I have. This has been tested on the Nintendo Wii so far, but I plan on also using it on the GameCube, Wii U and Apple G4. These changes aren=E2=80=99t the only ones required to get the kernel to co= mpile and link on PowerPC, libcore will also have to be changed to not use integer division to format u64, u128 and core::time::Duration, otherwise __udivdi3() and __umoddi3() will have to be added. I have tested this change by replacing the three implementations with unimplemented!() and it linked just fine. Signed-off-by: Link Mauve --- Documentation/rust/arch-support.rst | 1 + arch/powerpc/Kconfig | 1 + arch/powerpc/Makefile | 2 ++ arch/powerpc/include/asm/jump_label.h | 16 ++++++++++------ rust/Makefile | 4 +++- scripts/generate_rust_target.rs | 10 ++++++++++ 6 files changed, 27 insertions(+), 7 deletions(-) diff --git a/Documentation/rust/arch-support.rst b/Documentation/rust/arch-= support.rst index 6e6a515d0899..70b9e192a7a0 100644 --- a/Documentation/rust/arch-support.rst +++ b/Documentation/rust/arch-support.rst @@ -18,6 +18,7 @@ Architecture Level of support Constraints ``arm`` Maintained ARMv7 Little Endian only. ``arm64`` Maintained Little Endian only. ``loongarch`` Maintained \- +``powerpc`` Maintained 32-bit Big Endian only. ``riscv`` Maintained ``riscv64`` and LLVM/Clang only. ``um`` Maintained \- ``x86`` Maintained ``x86_64`` only. diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 9537a61ebae0..17db23b82e91 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -283,6 +283,7 @@ config PPC select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RELIABLE_STACKTRACE select HAVE_RSEQ + select HAVE_RUST if PPC32 select HAVE_SAMPLE_FTRACE_DIRECT if HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_SAMPLE_FTRACE_DIRECT_MULTI if HAVE_DYNAMIC_FTRACE_WITH_DIRECT= _CALLS select HAVE_SETUP_PER_CPU_AREA if PPC64 diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index a58b1029592c..9fd82c75dcbd 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -61,6 +61,8 @@ else KBUILD_LDFLAGS_MODULE +=3D $(objtree)/arch/powerpc/lib/crtsavres.o endif =20 +KBUILD_RUSTFLAGS +=3D --target=3Dpowerpc-unknown-linux-gnu + ifdef CONFIG_CPU_LITTLE_ENDIAN KBUILD_CPPFLAGS +=3D -mlittle-endian KBUILD_LDFLAGS +=3D -EL diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/a= sm/jump_label.h index d4eaba459a0e..238f0f625a36 100644 --- a/arch/powerpc/include/asm/jump_label.h +++ b/arch/powerpc/include/asm/jump_label.h @@ -15,14 +15,18 @@ #define JUMP_ENTRY_TYPE stringify_in_c(FTR_ENTRY_LONG) #define JUMP_LABEL_NOP_SIZE 4 =20 +/* This macro is also expanded on the Rust side. */ +#define ARCH_STATIC_BRANCH_ASM(key, label) \ + "1:\n\t" \ + "nop # arch_static_branch\n\t" \ + ".pushsection __jump_table, \"aw\"\n\t" \ + ".long 1b - ., " label " - .\n\t" \ + JUMP_ENTRY_TYPE key " - .\n\t" \ + ".popsection \n\t" + static __always_inline bool arch_static_branch(struct static_key *key, boo= l branch) { - asm goto("1:\n\t" - "nop # arch_static_branch\n\t" - ".pushsection __jump_table, \"aw\"\n\t" - ".long 1b - ., %l[l_yes] - .\n\t" - JUMP_ENTRY_TYPE "%c0 - .\n\t" - ".popsection \n\t" + asm goto(ARCH_STATIC_BRANCH_ASM("%c0", "%l[l_yes]") : : "i" (&((char *)key)[branch]) : : l_yes); =20 return false; diff --git a/rust/Makefile b/rust/Makefile index 5c0155b83454..377e6fd68524 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -400,13 +400,15 @@ bindgen_skip_c_flags :=3D -mno-fp-ret-in-387 -mprefer= red-stack-boundary=3D% \ -fno-inline-functions-called-once -fsanitize=3Dbounds-strict \ -fstrict-flex-arrays=3D% -fmin-function-alignment=3D% \ -fzero-init-padding-bits=3D% -mno-fdpic \ - --param=3D% --param asan-% -fno-isolate-erroneous-paths-dereference + --param=3D% --param asan-% -fno-isolate-erroneous-paths-dereference \ + -ffixed-r2 -mmultiple -mno-readonly-in-sdata =20 # Derived from `scripts/Makefile.clang`. BINDGEN_TARGET_x86 :=3D x86_64-linux-gnu BINDGEN_TARGET_arm64 :=3D aarch64-linux-gnu BINDGEN_TARGET_arm :=3D arm-linux-gnueabi BINDGEN_TARGET_loongarch :=3D loongarch64-linux-gnusf +BINDGEN_TARGET_powerpc :=3D powerpc-linux-gnu BINDGEN_TARGET_um :=3D $(BINDGEN_TARGET_$(SUBARCH)) BINDGEN_TARGET :=3D $(BINDGEN_TARGET_$(SRCARCH)) =20 diff --git a/scripts/generate_rust_target.rs b/scripts/generate_rust_target= .rs index 38b3416bb979..0054880ba0ea 100644 --- a/scripts/generate_rust_target.rs +++ b/scripts/generate_rust_target.rs @@ -188,6 +188,16 @@ fn main() { panic!("arm uses the builtin rustc target"); } else if cfg.has("ARM64") { panic!("arm64 uses the builtin rustc aarch64-unknown-none target"); + } else if cfg.has("PPC32") { + ts.push("arch", "powerpc"); + ts.push("data-layout", "E-m:e-p:32:32-Fn32-i64:64-n32"); + ts.push("features", "+soft-float"); + ts.push("llvm-target", "powerpc-unknown-eabi"); + if cfg.rustc_version_atleast(1, 91, 0) { + ts.push("target-pointer-width", 32); + } else { + ts.push("target-pointer-width", "32"); + } } else if cfg.has("RISCV") { if cfg.has("64BIT") { panic!("64-bit RISC-V uses the builtin rustc riscv64-unknown-n= one-elf target"); --=20 2.52.0