diff options
| author | Miguel Ojeda <ojeda@kernel.org> | 2024-04-09 18:25:16 +0100 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-04-28 14:50:34 -0700 |
| commit | 70a57b247251aabadd67795c3097c0fcc616e533 (patch) | |
| tree | 67d97ccdefffbbf84a4ba3cb750739ac25cba0a5 /arch/riscv | |
| parent | 300ce44cbe2924aa83330fc5f24e035665f51b03 (diff) | |
RISC-V: enable building 64-bit kernels with rust support
The rust modules work on 64-bit RISC-V, with no twiddling required.
Select HAVE_RUST and provide the required flags to kbuild so that the
modules can be used. The Makefile and Kconfig changes are lifted from
work done by Miguel in the Rust-for-Linux tree, hence his authorship.
Following the rabbit hole, the Makefile changes originated in a script,
created based on config files originally added by Gary, hence his
co-authorship.
32-bit is broken in core rust code, so support is limited to 64-bit:
ld.lld: error: undefined symbol: __udivdi3
As 64-bit RISC-V is now supported, add it to the arch support table.
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Co-developed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240409-silencer-book-ce1320f06aab@spud
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv')
| -rw-r--r-- | arch/riscv/Kconfig | 1 | ||||
| -rw-r--r-- | arch/riscv/Makefile | 7 |
2 files changed, 8 insertions, 0 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index be09c8836d56..cad31864fd0f 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -155,6 +155,7 @@ config RISCV select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RETHOOK if !XIP_KERNEL select HAVE_RSEQ + select HAVE_RUST if 64BIT select HAVE_SAMPLE_FTRACE_DIRECT select HAVE_SAMPLE_FTRACE_DIRECT_MULTI select HAVE_STACKPROTECTOR diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index a74e70405d3f..1a2dca1e6a96 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -34,6 +34,9 @@ ifeq ($(CONFIG_ARCH_RV64I),y) KBUILD_AFLAGS += -mabi=lp64 KBUILD_LDFLAGS += -melf64lriscv + + KBUILD_RUSTFLAGS += -Ctarget-cpu=generic-rv64 --target=riscv64imac-unknown-none-elf \ + -Cno-redzone else BITS := 32 UTS_MACHINE := riscv32 @@ -68,6 +71,10 @@ riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c riscv-march-$(CONFIG_RISCV_ISA_V) := $(riscv-march-y)v +ifneq ($(CONFIG_RISCV_ISA_C),y) + KBUILD_RUSTFLAGS += -Ctarget-feature=-c +endif + ifdef CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC KBUILD_CFLAGS += -Wa,-misa-spec=2.2 KBUILD_AFLAGS += -Wa,-misa-spec=2.2 |