tools/nolibc: add support for OpenRISC / or1k

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 <linux@weissschuh.net>
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260429-nolibc-openrisc-v2-1-8d7d7a2f3fec@weissschuh.net

diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile
index 872c318f50d41a949e4b29ba37a8a683b2026b78..2cb4d610fe535cef7171a2dff26d41a08d6b3aaf 100644 (file)
--- 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 (file)
index 0000000..5ef82fd
--- /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 <linux@weissschuh.net>
+ */
+
+#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 a3adaf433f2cccfdd9df70839ef764cc07331eff..55009dcafe9e16e9c6c9ef89cc563ef43acb466b 100644 (file)
--- 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 41d616a01db5b0677197b6c9e9eae221ca4c023e..26cc976536257a5e190feaa99acee20c92432181 100644 (file)
--- a/tools/testing/selftests/nolibc/Makefile.nolibc
+++ b/tools/testing/selftests/nolibc/Makefile.nolibc
@@ -102,6 +102,7 @@ DEFCONFIG_sparc32    = sparc32_defconfig
 DEFCONFIG_sparc64    = sparc64_defconfig
 DEFCONFIG_m68k       = virt_defconfig
 DEFCONFIG_sh4        = rts7751r2dplus_defconfig
+DEFCONFIG_openrisc   = virt_defconfig
 DEFCONFIG            = $(or $(DEFCONFIG_$(XARCH)),defconfig)
 
 EXTRACONFIG_x32       = -e CONFIG_X86_X32_ABI
@@ -128,6 +129,7 @@ QEMU_ARCH_mips64be   = mips64
 QEMU_ARCH_ppc64le    = ppc64
 QEMU_ARCH_loongarch  = loongarch64
 QEMU_ARCH_sparc32    = sparc
+QEMU_ARCH_openrisc   = or1k
 QEMU_ARCH            = $(or $(QEMU_ARCH_$(XARCH)),$(XARCH))
 
 QEMU_ARCH_USER_ppc64le = ppc64le
@@ -167,6 +169,7 @@ 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
@@ -201,6 +204,7 @@ 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 cd439096fdf35dfad1be5cb7677b02fcffe4c7c9..c25ee4be2df43282d4d266e801e5ee9228d70bea 100755 (executable)
--- 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