[PATCH] tools/nolibc: add 64-bit parisc support

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 <[email protected]>
---
 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 <[email protected]>