[PATCH 0/3] tools/nolibc: add support for SuperH

[PATCH 0/3] tools/nolibc: add support for SuperH

[Thomas Weißschuh]

Add support for SuperH/"sh" to nolibc.
Only sh4 is tested for now.

This is only tested on QEMU so far.
Additional testing would be very welcome.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
Thomas Weißschuh (3):
      selftests/nolibc: fix EXTRACONFIG variables ordering
      selftests/nolibc: use file driver for QEMU serial
      tools/nolibc: add support for SuperH

 tools/include/nolibc/arch-sh.h              | 162 ++++++++++++++++++++++++++++
 tools/include/nolibc/arch.h                 |   2 +
 tools/testing/selftests/nolibc/Makefile     |  15 ++-
 tools/testing/selftests/nolibc/run-tests.sh |   3 +-
 4 files changed, 177 insertions(+), 5 deletions(-)
---
base-commit: 6275a61db2f0586b8a5d651dfc7b4aacf9d0b2d6
change-id: 20250528-nolibc-sh-8b4e3bb8efcb

Best regards,
-- 
Thomas Weißschuh <linux@weissschuh.net>

[PATCH 1/3] selftests/nolibc: fix EXTRACONFIG variables ordering

[Thomas Weißschuh]

The variable block got disordered at some point.

Use the correct ordering.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 853f3a846d4c0fb187922d3063ec3d1a9a30ae46..22da78a4bfea0274f66abec319d34b3d2a2824ac 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -107,10 +107,10 @@ DEFCONFIG_sparc64    = sparc64_defconfig
 DEFCONFIG_m68k       = virt_defconfig
 DEFCONFIG            = $(DEFCONFIG_$(XARCH))
 
-EXTRACONFIG_m68k      = -e CONFIG_BLK_DEV_INITRD
-EXTRACONFIG           = $(EXTRACONFIG_$(XARCH))
 EXTRACONFIG_arm       = -e CONFIG_NAMESPACES
 EXTRACONFIG_armthumb  = -e CONFIG_NAMESPACES
+EXTRACONFIG_m68k      = -e CONFIG_BLK_DEV_INITRD
+EXTRACONFIG           = $(EXTRACONFIG_$(XARCH))
 
 # optional tests to run (default = all)
 TEST =

-- 
2.49.0

[PATCH 2/3] selftests/nolibc: use file driver for QEMU serial

[Thomas Weißschuh]

For the test implementation of the SuperH architecture a second serial
serial port needs to be used. Unfortunately the currently used 'stdio'
driver does not support multiple serial ports at the same time.

Switch to the 'file' driver which does support multiple ports and is
sufficient for the nolibc-test usecase.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 22da78a4bfea0274f66abec319d34b3d2a2824ac..238acaa7bb06dcdbcadd9d3190c2de726e1a40b1 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -315,12 +315,12 @@ kernel-standalone: initramfs | defconfig
 
 # run the tests after building the kernel
 run: kernel initramfs.cpio
-	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out"
+	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial file:/dev/stdout $(QEMU_ARGS) > "$(CURDIR)/run.out"
 	$(Q)$(REPORT) $(CURDIR)/run.out
 
 # re-run the tests from an existing kernel
 rerun:
-	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out"
+	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial file:/dev/stdout $(QEMU_ARGS) > "$(CURDIR)/run.out"
 	$(Q)$(REPORT) $(CURDIR)/run.out
 
 # report with existing test log

-- 
2.49.0

Re: [PATCH 2/3] selftests/nolibc: use file driver for QEMU serial

[Willy Tarreau]

Hi Thomas,

On Mon, Jun 09, 2025 at 11:28:58AM +0200, Thomas Weißschuh wrote:
> For the test implementation of the SuperH architecture a second serial
> serial port needs to be used. Unfortunately the currently used 'stdio'
> driver does not support multiple serial ports at the same time.
> 
> Switch to the 'file' driver which does support multiple ports and is
> sufficient for the nolibc-test usecase.
> 
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> ---
>  tools/testing/selftests/nolibc/Makefile | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
> index 22da78a4bfea0274f66abec319d34b3d2a2824ac..238acaa7bb06dcdbcadd9d3190c2de726e1a40b1 100644
> --- a/tools/testing/selftests/nolibc/Makefile
> +++ b/tools/testing/selftests/nolibc/Makefile
> @@ -315,12 +315,12 @@ kernel-standalone: initramfs | defconfig
>  
>  # run the tests after building the kernel
>  run: kernel initramfs.cpio
> -	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out"
> +	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial file:/dev/stdout $(QEMU_ARGS) > "$(CURDIR)/run.out"
>  	$(Q)$(REPORT) $(CURDIR)/run.out
>  
>  # re-run the tests from an existing kernel
>  rerun:
> -	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out"
> +	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(IMAGE)" -initrd initramfs.cpio -serial file:/dev/stdout $(QEMU_ARGS) > "$(CURDIR)/run.out"

I'm cautious every time we touch the -serial output after having faced
issues earlier when trying to use pipes. Here I think it's OK, however,
I'm wondering if "file:$(CURDIR)/run.out" wouldn't be clearer, and also
encourage future changes to stick to a file and avoid piping the output
to a filter command. No strong opinion though.

In any case: Acked-by: Willy Tarreau <w@1wt.eu>

Thanks,
Willy

[PATCH 3/3] tools/nolibc: add support for SuperH

[Thomas Weißschuh]

Add support for SuperH/"sh" to nolibc.
Only sh4 is tested for now.

The startup code is special:

__nolibc_entrypoint_epilogue() calls __builtin_unreachable() which emits
a call to abort(). To make this work a function prologue is generated to
set up a GOT pointer which corrupts "sp".
__builtin_unreachable() is necessary for __attribute__((noreturn)).
Also depending on compiler flags (for example -fPIC) even more prologue
is generated.

Work around this by defining a nested function in asm.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70216
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-sh.h              | 162 ++++++++++++++++++++++++++++
 tools/include/nolibc/arch.h                 |   2 +
 tools/testing/selftests/nolibc/Makefile     |   7 ++
 tools/testing/selftests/nolibc/run-tests.sh |   3 +-
 4 files changed, 173 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-sh.h b/tools/include/nolibc/arch-sh.h
new file mode 100644
index 0000000000000000000000000000000000000000..1ad006cba0f627f663eea36b41bc7399cca4addb
--- /dev/null
+++ b/tools/include/nolibc/arch-sh.h
@@ -0,0 +1,162 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * SuperH specific definitions for NOLIBC
+ * Copyright (C) 2025 Thomas Weißschuh <linux@weissschuh.net>
+ */
+
+#ifndef _NOLIBC_ARCH_SH_H
+#define _NOLIBC_ARCH_SH_H
+
+#include "compiler.h"
+#include "crt.h"
+
+/*
+ * Syscalls for SuperH:
+ *   - registers are 32bit wide
+ *   - syscall number is passed in r3
+ *   - arguments are in r4, r5, r6, r7, r0, r1, r2
+ *   - the system call is performed by calling trapa #31
+ *   - syscall return value is in r0
+ */
+
+#define my_syscall0(num)                                                      \
+({                                                                            \
+	register long _num __asm__ ("r3") = (num);                            \
+	register long _ret __asm__ ("r0");                                    \
+									      \
+	__asm__ volatile (                                                    \
+		"trapa #31"                                                   \
+		: "+r"(_ret)                                                  \
+		: "r"(_num)                                                   \
+		: "memory", "cc"                                              \
+	);                                                                    \
+	_ret;                                                                 \
+})
+
+#define my_syscall1(num, arg1)                                                \
+({                                                                            \
+	register long _num __asm__ ("r3") = (num);                            \
+	register long _ret __asm__ ("r0");                                    \
+	register long _arg1 __asm__ ("r4") = (long)(arg1);                    \
+									      \
+	__asm__ volatile (                                                    \
+		"trapa #31"                                                   \
+		: "=r"(_ret)                                                  \
+		: "r"(_num), "r"(_arg1)                                       \
+		: "memory", "cc"                                              \
+	);                                                                    \
+	_ret;                                                                 \
+})
+
+#define my_syscall2(num, arg1, arg2)                                          \
+({                                                                            \
+	register long _num __asm__ ("r3") = (num);                            \
+	register long _ret __asm__ ("r0");                                    \
+	register long _arg1 __asm__ ("r4") = (long)(arg1);                    \
+	register long _arg2 __asm__ ("r5") = (long)(arg2);                    \
+									      \
+	__asm__ volatile (                                                    \
+		"trapa #31"                                                   \
+		: "=r"(_ret)                                                  \
+		: "r"(_num), "r"(_arg1), "r"(_arg2)                           \
+		: "memory", "cc"                                              \
+	);                                                                    \
+	_ret;                                                                 \
+})
+
+#define my_syscall3(num, arg1, arg2, arg3)                                    \
+({                                                                            \
+	register long _num __asm__ ("r3") = (num);                            \
+	register long _ret __asm__ ("r0");                                    \
+	register long _arg1 __asm__ ("r4") = (long)(arg1);                    \
+	register long _arg2 __asm__ ("r5") = (long)(arg2);                    \
+	register long _arg3 __asm__ ("r6") = (long)(arg3);                    \
+									      \
+	__asm__ volatile (                                                    \
+		"trapa #31"                                                   \
+		: "=r"(_ret)                                                  \
+		: "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3)               \
+		: "memory", "cc"                                              \
+	);                                                                    \
+	_ret;                                                                 \
+})
+
+#define my_syscall4(num, arg1, arg2, arg3, arg4)                              \
+({                                                                            \
+	register long _num __asm__ ("r3") = (num);                            \
+	register long _ret __asm__ ("r0");                                    \
+	register long _arg1 __asm__ ("r4") = (long)(arg1);                    \
+	register long _arg2 __asm__ ("r5") = (long)(arg2);                    \
+	register long _arg3 __asm__ ("r6") = (long)(arg3);                    \
+	register long _arg4 __asm__ ("r7") = (long)(arg4);                    \
+									      \
+	__asm__ volatile (                                                    \
+		"trapa #31"                                                   \
+		: "=r"(_ret)                                                  \
+		: "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4)   \
+		: "memory", "cc"                                              \
+	);                                                                    \
+	_ret;                                                                 \
+})
+
+#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5)                        \
+({                                                                            \
+	register long _num __asm__ ("r3") = (num);                            \
+	register long _ret __asm__ ("r0");                                    \
+	register long _arg1 __asm__ ("r4") = (long)(arg1);                    \
+	register long _arg2 __asm__ ("r5") = (long)(arg2);                    \
+	register long _arg3 __asm__ ("r6") = (long)(arg3);                    \
+	register long _arg4 __asm__ ("r7") = (long)(arg4);                    \
+	register long _arg5 __asm__ ("r0") = (long)(arg5);                    \
+									      \
+	__asm__ volatile (                                                    \
+		"trapa #31"                                                   \
+		: "=r"(_ret)                                                  \
+		: "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4),  \
+		  "r"(_arg5)                                                  \
+		: "memory", "cc"                                              \
+	);                                                                    \
+	_ret;                                                                 \
+})
+
+#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6)                  \
+({                                                                            \
+	register long _num __asm__ ("r3") = (num);                            \
+	register long _ret __asm__ ("r0");                                    \
+	register long _arg1 __asm__ ("r4") = (long)(arg1);                    \
+	register long _arg2 __asm__ ("r5") = (long)(arg2);                    \
+	register long _arg3 __asm__ ("r6") = (long)(arg3);                    \
+	register long _arg4 __asm__ ("r7") = (long)(arg4);                    \
+	register long _arg5 __asm__ ("r0") = (long)(arg5);                    \
+	register long _arg6 __asm__ ("r1") = (long)(arg6);                    \
+									      \
+	__asm__ volatile (                                                    \
+		"trapa #31"                                                   \
+		: "=r"(_ret)                                                  \
+		: "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4),  \
+		  "r"(_arg5), "r"(_arg6)                                      \
+		: "memory", "cc"                                              \
+	);                                                                    \
+	_ret;                                                                 \
+})
+
+/* startup code */
+void _start_wrapper(void);
+void __attribute__((weak,noreturn)) __nolibc_entrypoint __no_stack_protector _start_wrapper(void)
+{
+	__asm__ volatile (
+		".global _start\n"           /* The C function will have a prologue,         */
+		".type _start, @function\n"  /* corrupting "sp"                              */
+		".weak _start\n"
+		"_start:\n"
+
+		"mov sp, r4\n"               /* save argc pointer to r4, as arg1 of _start_c */
+		"bsr _start_c\n"             /* transfer to c runtime                        */
+		"nop\n"                      /* delay slot                                   */
+
+		".size _start, .-_start\n"
+	);
+	__nolibc_entrypoint_epilogue();
+}
+
+#endif /* _NOLIBC_ARCH_SH_H */
diff --git a/tools/include/nolibc/arch.h b/tools/include/nolibc/arch.h
index d20b2304aac21bf817f02a085653d5a170546072..4cd10ebf2addca9a2a1f5ab5bb691ac7dfd4aa29 100644
--- a/tools/include/nolibc/arch.h
+++ b/tools/include/nolibc/arch.h
@@ -37,6 +37,8 @@
 #include "arch-sparc.h"
 #elif defined(__m68k__)
 #include "arch-m68k.h"
+#elif defined(__sh__)
+#include "arch-sh.h"
 #else
 #error Unsupported Architecture
 #endif
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 238acaa7bb06dcdbcadd9d3190c2de726e1a40b1..65a2442c6709241e410dd08af9ab6b0b0691e7a7 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -58,6 +58,7 @@ ARCH_riscv64     = riscv
 ARCH_s390x       = s390
 ARCH_sparc32     = sparc
 ARCH_sparc64     = sparc
+ARCH_sh4         = sh
 ARCH            := $(or $(ARCH_$(XARCH)),$(XARCH))
 
 # kernel image names by architecture
@@ -81,6 +82,7 @@ IMAGE_loongarch  = arch/loongarch/boot/vmlinuz.efi
 IMAGE_sparc32    = arch/sparc/boot/image
 IMAGE_sparc64    = arch/sparc/boot/image
 IMAGE_m68k       = vmlinux
+IMAGE_sh4        = arch/sh/boot/zImage
 IMAGE            = $(objtree)/$(IMAGE_$(XARCH))
 IMAGE_NAME       = $(notdir $(IMAGE))
 
@@ -105,11 +107,13 @@ DEFCONFIG_loongarch  = defconfig
 DEFCONFIG_sparc32    = sparc32_defconfig
 DEFCONFIG_sparc64    = sparc64_defconfig
 DEFCONFIG_m68k       = virt_defconfig
+DEFCONFIG_sh4        = rts7751r2dplus_defconfig
 DEFCONFIG            = $(DEFCONFIG_$(XARCH))
 
 EXTRACONFIG_arm       = -e CONFIG_NAMESPACES
 EXTRACONFIG_armthumb  = -e CONFIG_NAMESPACES
 EXTRACONFIG_m68k      = -e CONFIG_BLK_DEV_INITRD
+EXTRACONFIG_sh4       = -e CONFIG_BLK_DEV_INITRD -e CONFIG_CMDLINE_FROM_BOOTLOADER
 EXTRACONFIG           = $(EXTRACONFIG_$(XARCH))
 
 # optional tests to run (default = all)
@@ -136,6 +140,7 @@ QEMU_ARCH_loongarch  = loongarch64
 QEMU_ARCH_sparc32    = sparc
 QEMU_ARCH_sparc64    = sparc64
 QEMU_ARCH_m68k       = m68k
+QEMU_ARCH_sh4        = sh4
 QEMU_ARCH            = $(QEMU_ARCH_$(XARCH))
 
 QEMU_ARCH_USER_ppc64le = ppc64le
@@ -169,6 +174,7 @@ QEMU_ARGS_loongarch  = -M virt -append "console=ttyS0,115200 panic=-1 $(TEST:%=N
 QEMU_ARGS_sparc32    = -M SS-5 -m 256M -append "console=ttyS0,115200 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
 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            = -m 1G $(QEMU_ARGS_$(XARCH)) $(QEMU_ARGS_BIOS) $(QEMU_ARGS_EXTRA)
 
 # OUTPUT is only set when run from the main makefile, otherwise
@@ -192,6 +198,7 @@ CFLAGS_s390 = -m31
 CFLAGS_mips32le = -EL -mabi=32 -fPIC
 CFLAGS_mips32be = -EB -mabi=32
 CFLAGS_sparc32 = $(call cc-option,-m32)
+CFLAGS_sh4 = -ml -m4
 ifeq ($(origin XARCH),command line)
 CFLAGS_XARCH = $(CFLAGS_$(XARCH))
 endif
diff --git a/tools/testing/selftests/nolibc/run-tests.sh b/tools/testing/selftests/nolibc/run-tests.sh
index 8277599e6441a933d9c1ec5003acf49b06df226f..8f6addb01d22d9532e2ef367692168787c23dc1f 100755
--- a/tools/testing/selftests/nolibc/run-tests.sh
+++ b/tools/testing/selftests/nolibc/run-tests.sh
@@ -27,6 +27,7 @@ all_archs=(
 	loongarch
 	sparc32 sparc64
 	m68k
+	sh4
 )
 archs="${all_archs[@]}"
 
@@ -187,7 +188,7 @@ test_arch() {
 		echo "Unsupported configuration"
 		return
 	fi
-	if [ "$arch" = "m68k" ] && [ "$llvm" = "1" ]; then
+	if [ "$arch" = "m68k" -o "$arch" = "sh4" ] && [ "$llvm" = "1" ]; then
 		echo "Unsupported configuration"
 		return
 	fi

-- 
2.49.0

Re: [PATCH 0/3] tools/nolibc: add support for SuperH

[John Paul Adrian Glaubitz]

Hi Thomas,

On Mon, 2025-06-09 at 11:28 +0200, Thomas Weißschuh wrote:
> Add support for SuperH/"sh" to nolibc.
> Only sh4 is tested for now.
> 
> This is only tested on QEMU so far.
> Additional testing would be very welcome.
> 
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> ---
> Thomas Weißschuh (3):
>       selftests/nolibc: fix EXTRACONFIG variables ordering
>       selftests/nolibc: use file driver for QEMU serial
>       tools/nolibc: add support for SuperH
> 
>  tools/include/nolibc/arch-sh.h              | 162 ++++++++++++++++++++++++++++
>  tools/include/nolibc/arch.h                 |   2 +
>  tools/testing/selftests/nolibc/Makefile     |  15 ++-
>  tools/testing/selftests/nolibc/run-tests.sh |   3 +-
>  4 files changed, 177 insertions(+), 5 deletions(-)
> ---
> base-commit: 6275a61db2f0586b8a5d651dfc7b4aacf9d0b2d6
> change-id: 20250528-nolibc-sh-8b4e3bb8efcb

I have no experience with the selftest code but I can definitely test
on real hardware if you can point me to some instructions on how to
run the tests.

CC Geert.

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913

Re: [PATCH 0/3] tools/nolibc: add support for SuperH

[Thomas Weißschuh]

Hi Adrian,

On 2025-06-09 11:53:25+0200, John Paul Adrian Glaubitz wrote:
> On Mon, 2025-06-09 at 11:28 +0200, Thomas Weißschuh wrote:
> > Add support for SuperH/"sh" to nolibc.
> > Only sh4 is tested for now.
> > 
> > This is only tested on QEMU so far.
> > Additional testing would be very welcome.
> > 
> > Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> > ---
> > Thomas Weißschuh (3):
> >       selftests/nolibc: fix EXTRACONFIG variables ordering
> >       selftests/nolibc: use file driver for QEMU serial
> >       tools/nolibc: add support for SuperH
> > 
> >  tools/include/nolibc/arch-sh.h              | 162 ++++++++++++++++++++++++++++
> >  tools/include/nolibc/arch.h                 |   2 +
> >  tools/testing/selftests/nolibc/Makefile     |  15 ++-
> >  tools/testing/selftests/nolibc/run-tests.sh |   3 +-
> >  4 files changed, 177 insertions(+), 5 deletions(-)
> > ---
> > base-commit: 6275a61db2f0586b8a5d651dfc7b4aacf9d0b2d6
> > change-id: 20250528-nolibc-sh-8b4e3bb8efcb
> 
> I have no experience with the selftest code but I can definitely test
> on real hardware if you can point me to some instructions on how to
> run the tests.

That would be much appreciated.
You can compile the selftests like this:

$ cd tools/testing/selftests/nolibc
$ make [CC= CFLAGS_EXTRA=] nolibc-test
$ ./nolibc-test

The test executable is fully self-contained, you can also cross-compile
it and copy it around.


Thomas

Re: [PATCH 0/3] tools/nolibc: add support for SuperH

[Rob Landley]

On 6/9/25 04:28, Thomas Weißschuh wrote:
> Add support for SuperH/"sh" to nolibc.
> Only sh4 is tested for now.
> 
> This is only tested on QEMU so far.
> Additional testing would be very welcome.

I ran this by Jeff Dionne (the j-core architect) who said:

 > Looks correct to me.  There are no endian assumptions that I can see.

So you can put

Acked-by: Rob Landley <rob@landley.net>
Acked-by: D. Jeff Dionne <jeff@coresemi.io>

But neither of us really have a build environment set up to do much with 
it. Is there a howto for this, or is just to run the kernel tests?

Rob

Re: [PATCH 0/3] tools/nolibc: add support for SuperH

[Thomas Weißschuh]

Hi Rob,

On 2025-06-24 21:41:14-0500, Rob Landley wrote:
> On 6/9/25 04:28, Thomas Weißschuh wrote:
> > Add support for SuperH/"sh" to nolibc.
> > Only sh4 is tested for now.
> > 
> > This is only tested on QEMU so far.
> > Additional testing would be very welcome.
> 
> I ran this by Jeff Dionne (the j-core architect) who said:
> 
> > Looks correct to me.  There are no endian assumptions that I can see.
> 
> So you can put
> 
> Acked-by: Rob Landley <rob@landley.net>
> Acked-by: D. Jeff Dionne <jeff@coresemi.io>

Thanks!

> But neither of us really have a build environment set up to do much with it.
> Is there a howto for this, or is just to run the kernel tests?

v2 of the series [0] has some test instructions.
These should also work with v1, except that "-f Makefile.nolibc" needs
to be removed.

$ cd tools/testings/selftests/nolibc/
$ make -f Makefile.nolibc ARCH=sh CROSS_COMPILE=sh4-linux- nolibc-test
$ file nolibc-test
nolibc-test: ELF 32-bit LSB executable, Renesas SH, version 1 (SYSV), statically linked, not stripped
$ ./nolibc-test
Running test 'startup'
0 argc = 1                                                        [OK]
...
Total number of errors: 0
Exiting with status 0

[0] https://lore.kernel.org/lkml/20250623-nolibc-sh-v2-0-0f5b4b303025@weissschuh.net/

Re: [PATCH 0/3] tools/nolibc: add support for SuperH

[John Paul Adrian Glaubitz]

Hi Thomas,

On Wed, 2025-06-25 at 16:13 +0200, Thomas Weißschuh wrote:
> > But neither of us really have a build environment set up to do much with it.
> > Is there a howto for this, or is just to run the kernel tests?
> 
> v2 of the series [0] has some test instructions.
> These should also work with v1, except that "-f Makefile.nolibc" needs
> to be removed.
> 
> $ cd tools/testings/selftests/nolibc/

There is a typo here. It should be "testing". But I guess since this text doesn't
end up in the commits anyway, it's nothing to worry about. Unless it's part of
the documentation.

> $ make -f Makefile.nolibc ARCH=sh CROSS_COMPILE=sh4-linux- nolibc-test
> $ file nolibc-test
> nolibc-test: ELF 32-bit LSB executable, Renesas SH, version 1 (SYSV), statically linked, not stripped
> $ ./nolibc-test
> Running test 'startup'
> 0 argc = 1                                                        [OK]
> ...
> Total number of errors: 0
> Exiting with status 0

Adrian

-- 
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