[PATCH] tools/nolibc: add 64-bit parisc support
From: Thomas Weißschuh
Date: Thu Aug 20 2026 - 05:39:42 EST
Extend the existing parisc support to also handle 64-bit mode.
Some peculiarities:
* The nonstandard ftruncate64 system call requires a workaround.
* The linker defaults to main() as entry point, which needs to be
switched to _start() explicitly.
* The linker defaults to dynamic linking, which needs to be disabled
explicitly.
* With the default -Os, gcc does not use 64-bit multiplication
instructions, requiring libgcc. Use -O2 instead.
* There is no qemu-user available.
* CONFIG_COMPAT needs to be disabled to avoid build errors due to a
missing 32-bit vDSO compiler.
Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
tools/include/nolibc/arch-parisc.h | 26 +++++++++++++++++++++++---
tools/include/nolibc/stdlib.h | 2 +-
tools/testing/selftests/nolibc/Makefile.nolibc | 5 +++++
tools/testing/selftests/nolibc/run-tests.sh | 7 ++++---
4 files changed, 33 insertions(+), 7 deletions(-)
diff --git a/tools/include/nolibc/arch-parisc.h b/tools/include/nolibc/arch-parisc.h
index 417043ecbc53..fd0d1dccabf3 100644
--- a/tools/include/nolibc/arch-parisc.h
+++ b/tools/include/nolibc/arch-parisc.h
@@ -7,9 +7,7 @@
#ifndef _NOLIBC_ARCH_PARISC_H
#define _NOLIBC_ARCH_PARISC_H
-#if defined(__LP64__)
-#error 64-bit not supported
-#endif
+#include <linux/unistd.h>
#include "compiler.h"
#include "crt.h"
@@ -167,9 +165,15 @@
void __attribute__((weak, noreturn)) __nolibc_entrypoint __nolibc_no_stack_protector _start(void)
{
__asm__ volatile (
+#ifdef __LP64__
+ ".import __gp\n" /* Set up the dp register */
+ "ldil L%__gp, %dp\n"
+ "ldo R%__gp(%r27), %dp\n"
+#else
".import $global$\n" /* Set up the dp register */
"ldil L%$global$, %dp\n"
"ldo R%$global$(%r27), %dp\n"
+#endif
"b _start_c\n" /* Call _start_c, the load below is executed first */
@@ -182,4 +186,20 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __nolibc_no_stack_prote
}
#endif /* NOLIBC_NO_RUNTIME */
+#ifdef __LP64__
+/*
+ * This override is normally only meant for 32-bit architectures.
+ * Put parisc 64-bit has __NR_ftruncate64, so this path is taken.
+ * Add an unused second argument to satisfy the calling convention.
+ */
+static __attribute__((unused))
+int _sys_ftruncate64(int fd, uint64_t length, uint64_t unused)
+{
+ (void)unused;
+
+ return __nolibc_syscall2(__NR_ftruncate64, fd, length);
+}
+#define _sys_ftruncate64 _sys_ftruncate64
+#endif
+
#endif /* _NOLIBC_ARCH_PARISC_H */
diff --git a/tools/include/nolibc/stdlib.h b/tools/include/nolibc/stdlib.h
index 1816c2368b68..6c3c620a04cf 100644
--- a/tools/include/nolibc/stdlib.h
+++ b/tools/include/nolibc/stdlib.h
@@ -230,7 +230,7 @@ int _nolibc_u64toa_base(uint64_t in, char *buffer, unsigned int base, uint64_t r
/* Generate least significant digit first */
do {
-#if defined(__SIZEOF_INT128__) && !defined(__mips__) && !defined(__sparc__)
+#if defined(__SIZEOF_INT128__) && !defined(__mips__) && !defined(__sparc__) && !defined(__hppa__)
q = ((unsigned __int128)in * recip) >> 64;
#else
uint64_t p = (uint32_t)in * (recip >> 32);
diff --git a/tools/testing/selftests/nolibc/Makefile.nolibc b/tools/testing/selftests/nolibc/Makefile.nolibc
index d8b71cbfc173..3ca473ec35ef 100644
--- a/tools/testing/selftests/nolibc/Makefile.nolibc
+++ b/tools/testing/selftests/nolibc/Makefile.nolibc
@@ -65,6 +65,7 @@ ARCH_sparc32 = sparc
ARCH_sparc64 = sparc
ARCH_sh4 = sh
ARCH_parisc32 = parisc
+ARCH_parisc64 = parisc64
ARCH := $(or $(ARCH_$(XARCH)),$(XARCH))
# kernel image names by architecture
@@ -113,6 +114,7 @@ EXTRACONFIG_sparc32 = -e CONFIG_TMPFS
EXTRACONFIG_m68k = -e CONFIG_BLK_DEV_INITRD
EXTRACONFIG_sh4 = -e CONFIG_BLK_DEV_INITRD -e CONFIG_CMDLINE_FROM_BOOTLOADER
EXTRACONFIG_alpha = -e CONFIG_BLK_DEV_INITRD
+EXTRACONFIG_parisc64 = -d CONFIG_COMPAT
EXTRACONFIG = $(EXTRACONFIG_$(XARCH))
# optional tests to run (default = all)
@@ -134,6 +136,7 @@ QEMU_ARCH_loongarch = loongarch64
QEMU_ARCH_sparc32 = sparc
QEMU_ARCH_openrisc = or1k
QEMU_ARCH_parisc32 = hppa
+QEMU_ARCH_parisc64 = hppa
QEMU_ARCH = $(or $(QEMU_ARCH_$(XARCH)),$(XARCH))
QEMU_ARCH_USER_ppc64le = ppc64le
@@ -175,6 +178,7 @@ QEMU_ARGS_m68k = -M virt -append "console=ttyGF0,115200 panic=-1 $(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_parisc32 = -M B160L -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
+QEMU_ARGS_parisc64 = -M C3700 -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_alpha = -M clipper -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS = -m 1G $(QEMU_ARGS_$(XARCH)) $(QEMU_ARGS_BIOS) $(QEMU_ARGS_EXTRA)
@@ -193,6 +197,7 @@ CFLAGS_x32 = -mx32
CFLAGS_arm = -marm
CFLAGS_armthumb = -mthumb -march=armv6t2
CFLAGS_parisc32 = -mfast-indirect-calls
+CFLAGS_parisc64 = -Wl,--no-dynamic-linker -Wl,--entry=_start -O2
CFLAGS_ppc = -m32 -mbig-endian -mno-vsx $(call cc-option,-mmultiple)
CFLAGS_ppc64 = -m64 -mbig-endian -mno-vsx $(call cc-option,-mmultiple)
CFLAGS_ppc64le = -m64 -mlittle-endian -mno-vsx $(call cc-option,-mabi=elfv2)
diff --git a/tools/testing/selftests/nolibc/run-tests.sh b/tools/testing/selftests/nolibc/run-tests.sh
index 3da806e2b302..a50a47d9df2c 100755
--- a/tools/testing/selftests/nolibc/run-tests.sh
+++ b/tools/testing/selftests/nolibc/run-tests.sh
@@ -29,7 +29,7 @@ all_archs=(
sparc32 sparc64
m68k
sh4
- parisc32
+ parisc32 parisc64
alpha
hexagon
)
@@ -122,6 +122,7 @@ crosstool_arch() {
sparc*) echo sparc64;;
x32*) echo x86_64;;
parisc32) echo hppa;;
+ parisc64) echo hppa64;;
*) echo "$1";;
esac
}
@@ -206,11 +207,11 @@ test_arch() {
exit 1
esac
printf '%-15s' "$arch:"
- if [ "$arch" = "m68k" -o "$arch" = "sh4" -o "$arch" = "openrisc" -o "$arch" = "parisc32" -o "$arch" = "alpha" ] && [ "$llvm" = "1" ]; then
+ if [ "$arch" = "m68k" -o "$arch" = "sh4" -o "$arch" = "openrisc" -o "$arch" = "parisc*" -o "$arch" = "alpha" ] && [ "$llvm" = "1" ]; then
echo "Unsupported configuration"
return
fi
- if [ "$arch" = "x32" ] && [ "$test_mode" = "user" ]; then
+ if [ "$arch" = "x32" -o "$arch" = "parisc64" ] && [ "$test_mode" = "user" ]; then
echo "Unsupported configuration"
return
fi
---
base-commit: 7f4233794df172ab1d286dc0fbd70da2cc837654
change-id: 20260407-nolibc-parisc64-3ca0547c2af9
Best regards,
--
Thomas Weißschuh <linux@xxxxxxxxxxxxxx>