On Wed, Apr 29, 2026 at 05:20:45PM +0200, Thomas Weißschuh wrote: > Add support for OpenRISC / or1k to nolibc. > > _start() uses the same wrapper construct as in arch-sh.h. > libgcc is necessary as OpenRISC is missing 64-bit multiplication. > > Signed-off-by: Thomas Weißschuh <[email protected]>
Acked-by: Stafford Horne <[email protected]> Do you want me to pick this up to send via the openrisc queue? Or do you prefer it go via the selftests queue? > --- > Changes in v2: > - Drop useless l.nop from __nolibc_syscallX(). > - Use the delay slot after l.jal _start_c. > - Fix some typos. > - Use a single register variable for system call number and return. > - Use 'r1' register name over non-idiomatic 'sp' alias. > - Link to v1: > https://patch.msgid.link/[email protected] Thanks, I am ok with these. I didn't realize the 'sp' mnemonic worked. I don't have any opinion either way as to whether we should use it or not, as I suspect we have supported it in binutils/gas for a while. But I guess it's safer to leave it out as I haven't seen it used before now. -Stafford > --- > tools/include/nolibc/Makefile | 2 +- > tools/include/nolibc/arch-openrisc.h | 160 > +++++++++++++++++++++++++ > tools/include/nolibc/arch.h | 2 + > tools/testing/selftests/nolibc/Makefile.nolibc | 5 + > tools/testing/selftests/nolibc/run-tests.sh | 4 +- > 5 files changed, 171 insertions(+), 2 deletions(-) > > diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile > index 872c318f50d4..2cb4d610fe53 100644 > --- a/tools/include/nolibc/Makefile > +++ b/tools/include/nolibc/Makefile > @@ -17,7 +17,7 @@ endif > # it defaults to this nolibc directory. > OUTPUT ?= $(CURDIR)/ > > -architectures := arm arm64 loongarch m68k mips powerpc riscv s390 sh sparc > x86 > +architectures := arm arm64 loongarch m68k mips openrisc powerpc riscv s390 > sh sparc x86 > arch_files := arch.h $(addsuffix .h, $(addprefix arch-, $(architectures))) > all_files := \ > alloca.h \ > diff --git a/tools/include/nolibc/arch-openrisc.h > b/tools/include/nolibc/arch-openrisc.h > new file mode 100644 > index 000000000000..5ef82fd9cc64 > --- /dev/null > +++ b/tools/include/nolibc/arch-openrisc.h > @@ -0,0 +1,160 @@ > +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ > +/* > + * OpenRISC specific definitions for NOLIBC > + * Copyright (C) 2026 Thomas Weißschuh <[email protected]> > + */ > + > +#ifndef _NOLIBC_ARCH_OPENRISC_H > +#define _NOLIBC_ARCH_OPENRISC_H > + > +#include "compiler.h" > +#include "crt.h" > + > +/* > + * Syscalls for OpenRISC: > + * - syscall number is passed in r11 > + * - arguments are in r3, r4, r5, r6, r7, r8 > + * - the system call is performed by calling l.sys 1 > + * - syscall return value is in r11 > + */ > + > +#define _NOLIBC_SYSCALL_CLOBBERLIST \ > + "r12", "r13", "r15", "r17", "r19", "r21", "r23", "r25", "r27", "r29", > "r31", "memory" > + > +#define __nolibc_syscall0(num) > \ > +({ > \ > + register long _num __asm__ ("r11") = (num); \ > + \ > + __asm__ volatile ( \ > + "l.sys 1\n" \ > + : "+r"(_num) \ > + : \ > + : "r3", "r4", "r5", "r6", "r7", "r8", \ > + _NOLIBC_SYSCALL_CLOBBERLIST \ > + ); \ > + _num; \ > +}) > + > +#define __nolibc_syscall1(num, arg1) > \ > +({ > \ > + register long _num __asm__ ("r11") = (num); \ > + register long _arg1 __asm__ ("r3") = (long)(arg1); \ > + \ > + __asm__ volatile ( \ > + "l.sys 1\n" \ > + : "+r"(_num) \ > + : "r"(_arg1) \ > + : "r4", "r5", "r6", "r7", "r8", _NOLIBC_SYSCALL_CLOBBERLIST \ > + ); \ > + _num; \ > +}) > + > +#define __nolibc_syscall2(num, arg1, arg2) > \ > +({ > \ > + register long _num __asm__ ("r11") = (num); \ > + register long _arg1 __asm__ ("r3") = (long)(arg1); \ > + register long _arg2 __asm__ ("r4") = (long)(arg2); \ > + \ > + __asm__ volatile ( \ > + "l.sys 1\n" \ > + : "+r"(_num) \ > + : "r"(_arg1), "r"(_arg2) \ > + : "r5", "r6", "r7", "r8", _NOLIBC_SYSCALL_CLOBBERLIST \ > + ); \ > + _num; \ > +}) > + > +#define __nolibc_syscall3(num, arg1, arg2, arg3) > \ > +({ > \ > + register long _num __asm__ ("r11") = (num); \ > + register long _arg1 __asm__ ("r3") = (long)(arg1); \ > + register long _arg2 __asm__ ("r4") = (long)(arg2); \ > + register long _arg3 __asm__ ("r5") = (long)(arg3); \ > + \ > + __asm__ volatile ( \ > + "l.sys 1\n" \ > + : "+r"(_num) \ > + : "r"(_arg1), "r"(_arg2), "r"(_arg3) \ > + : "r6", "r7", "r8", _NOLIBC_SYSCALL_CLOBBERLIST \ > + ); \ > + _num; \ > +}) > + > +#define __nolibc_syscall4(num, arg1, arg2, arg3, arg4) > \ > +({ > \ > + register long _num __asm__ ("r11") = (num); \ > + register long _arg1 __asm__ ("r3") = (long)(arg1); \ > + register long _arg2 __asm__ ("r4") = (long)(arg2); \ > + register long _arg3 __asm__ ("r5") = (long)(arg3); \ > + register long _arg4 __asm__ ("r6") = (long)(arg4); \ > + \ > + __asm__ volatile ( \ > + "l.sys 1\n" \ > + : "+r"(_num) \ > + : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4) \ > + : "r7", "r8", _NOLIBC_SYSCALL_CLOBBERLIST \ > + ); \ > + _num; \ > +}) > + > +#define __nolibc_syscall5(num, arg1, arg2, arg3, arg4, arg5) > \ > +({ > \ > + register long _num __asm__ ("r11") = (num); \ > + register long _arg1 __asm__ ("r3") = (long)(arg1); \ > + register long _arg2 __asm__ ("r4") = (long)(arg2); \ > + register long _arg3 __asm__ ("r5") = (long)(arg3); \ > + register long _arg4 __asm__ ("r6") = (long)(arg4); \ > + register long _arg5 __asm__ ("r7") = (long)(arg5); \ > + \ > + __asm__ volatile ( \ > + "l.sys 1\n" \ > + : "+r"(_num) \ > + : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5) \ > + : "r8", _NOLIBC_SYSCALL_CLOBBERLIST \ > + ); \ > + _num; \ > +}) > + > +#define __nolibc_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) > \ > +({ > \ > + register long _num __asm__ ("r11") = (num); \ > + register long _arg1 __asm__ ("r3") = (long)(arg1); \ > + register long _arg2 __asm__ ("r4") = (long)(arg2); \ > + register long _arg3 __asm__ ("r5") = (long)(arg3); \ > + register long _arg4 __asm__ ("r6") = (long)(arg4); \ > + register long _arg5 __asm__ ("r7") = (long)(arg5); \ > + register long _arg6 __asm__ ("r8") = (long)(arg6); \ > + \ > + __asm__ volatile ( \ > + "l.sys 1\n" \ > + : "+r"(_num) \ > + : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \ > + "r"(_arg6) \ > + : _NOLIBC_SYSCALL_CLOBBERLIST \ > + ); \ > + _num; \ > +}) > + > +#ifndef NOLIBC_NO_RUNTIME > +/* startup code */ > +void _start_wrapper(void); > +void __attribute__((weak,noreturn)) > +__nolibc_entrypoint __nolibc_no_stack_protector > +_start_wrapper(void) > +{ > + __asm__ volatile ( > + ".global _start\n" /* The C function will have a > prologue, */ > + ".type _start, @function\n" /* corrupting "sp/r1" > */ > + ".weak _start\n" > + "_start:\n" > + > + "l.jal _start_c\n" /* transfer to c runtime > */ > + "l.or r3,r1,r1\n" /* save stack pointer to r3, as > arg1 of _start_c */ > + > + ".size _start, .-_start\n" > + ); > + __nolibc_entrypoint_epilogue(); > +} > +#endif /* NOLIBC_NO_RUNTIME */ > + > +#endif /* _NOLIBC_ARCH_OPENRISC_H */ > diff --git a/tools/include/nolibc/arch.h b/tools/include/nolibc/arch.h > index a3adaf433f2c..55009dcafe9e 100644 > --- a/tools/include/nolibc/arch.h > +++ b/tools/include/nolibc/arch.h > @@ -28,6 +28,8 @@ > #include "arch-m68k.h" > #elif defined(__sh__) > #include "arch-sh.h" > +#elif defined(__or1k__) > +#include "arch-openrisc.h" > #else > #error Unsupported Architecture > #endif > diff --git a/tools/testing/selftests/nolibc/Makefile.nolibc > b/tools/testing/selftests/nolibc/Makefile.nolibc > index f30bc68470cc..91f5a284f4e6 100644 > --- a/tools/testing/selftests/nolibc/Makefile.nolibc > +++ b/tools/testing/selftests/nolibc/Makefile.nolibc > @@ -92,6 +92,7 @@ IMAGE_sparc32 = arch/sparc/boot/image > IMAGE_sparc64 = arch/sparc/boot/image > IMAGE_m68k = vmlinux > IMAGE_sh4 = arch/sh/boot/zImage > +IMAGE_openrisc = vmlinux > IMAGE = $(objtree)/$(IMAGE_$(XARCH)) > IMAGE_NAME = $(notdir $(IMAGE)) > > @@ -121,6 +122,7 @@ DEFCONFIG_sparc32 = sparc32_defconfig > DEFCONFIG_sparc64 = sparc64_defconfig > DEFCONFIG_m68k = virt_defconfig > DEFCONFIG_sh4 = rts7751r2dplus_defconfig > +DEFCONFIG_openrisc = virt_defconfig > DEFCONFIG = $(DEFCONFIG_$(XARCH)) > > EXTRACONFIG_x32 = -e CONFIG_X86_X32_ABI > @@ -159,6 +161,7 @@ QEMU_ARCH_sparc32 = sparc > QEMU_ARCH_sparc64 = sparc64 > QEMU_ARCH_m68k = m68k > QEMU_ARCH_sh4 = sh4 > +QEMU_ARCH_openrisc = or1k > QEMU_ARCH = $(QEMU_ARCH_$(XARCH)) > > QEMU_ARCH_USER_ppc64le = ppc64le > @@ -199,6 +202,7 @@ QEMU_ARGS_sparc32 = -M SS-5 -m 256M -append > "console=ttyS0,115200 panic=-1 $( > QEMU_ARGS_sparc64 = -M sun4u -append "console=ttyS0,115200 panic=-1 > $(TEST:%=NOLIBC_TEST=%)" > QEMU_ARGS_m68k = -M virt -append "console=ttyGF0,115200 panic=-1 > $(TEST:%=NOLIBC_TEST=%)" > QEMU_ARGS_sh4 = -M r2d -serial file:/dev/stdout -append > "console=ttySC1,115200 panic=-1 $(TEST:%=NOLIBC_TEST=%)" > +QEMU_ARGS_openrisc = -M virt -m 512M -append "console=ttyS0 panic=-1 > $(TEST:%=NOLIBC_TEST=%)" > QEMU_ARGS = -m 1G $(QEMU_ARGS_$(XARCH)) $(QEMU_ARGS_BIOS) > $(QEMU_ARGS_EXTRA) > > # OUTPUT is only set when run from the main makefile, otherwise > @@ -233,6 +237,7 @@ CFLAGS_XARCH = $(CFLAGS_$(XARCH)) > endif > > LDLIBS_ppc = $(if $(LLVM),,-lgcc) > +LDLIBS_openrisc = $(if $(LLVM),,-lgcc) > LDLIBS = $(LDLIBS_$(XARCH)) > > include Makefile.include > diff --git a/tools/testing/selftests/nolibc/run-tests.sh > b/tools/testing/selftests/nolibc/run-tests.sh > index cd439096fdf3..c25ee4be2df4 100755 > --- a/tools/testing/selftests/nolibc/run-tests.sh > +++ b/tools/testing/selftests/nolibc/run-tests.sh > @@ -21,6 +21,7 @@ all_archs=( > i386 x86_64 x32 > arm64 arm armthumb > mips32le mips32be mipsn32le mipsn32be mips64le mips64be > + openrisc > ppc ppc64 ppc64le > riscv32 riscv64 > s390x > @@ -107,6 +108,7 @@ crosstool_arch() { > case "$1" in > arm64) echo aarch64;; > armthumb) echo arm;; > + openrisc) echo or1k;; > ppc) echo powerpc;; > ppc64) echo powerpc64;; > ppc64le) echo powerpc64;; > @@ -185,7 +187,7 @@ test_arch() { > exit 1 > esac > printf '%-15s' "$arch:" > - if [ "$arch" = "m68k" -o "$arch" = "sh4" ] && [ "$llvm" = "1" ]; then > + if [ "$arch" = "m68k" -o "$arch" = "sh4" -o "$arch" = "openrisc" ] && [ > "$llvm" = "1" ]; then > echo "Unsupported configuration" > return > fi > > --- > base-commit: 8bf37d924968cf26ab95f644c981a28086e372af > change-id: 20260415-nolibc-openrisc-a1ab91c41fe5 > > Best regards, > -- > Thomas Weißschuh <[email protected]> >
