Hi, Willy
Here is the v5, purely include the ppc parts, with two critical fixups
for the latest gcc 13.1.0 toolchain, now, both run and run-user pass.
Here is the run-user test report:
// with local toolchains
$ for arch in ppc ppc64 ppc64le; do make run-user XARCH=$arch | grep "status: "; done
165 test(s): 157 passed, 8 skipped, 0 failed => status: warning
165 test(s): 157 passed, 8 skipped, 0 failed => status: warning
165 test(s): 157 passed, 8 skipped, 0 failed => status: warning
// with latest toolchains
$ for arch in ppc ppc64 ppc64le; do make run-user XARCH=$arch CC=/path/to/gcc-13.1.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc | grep status; file nolibc-test; done
165 test(s): 157 passed, 8 skipped, 0 failed => status: warning
nolibc-test: ELF 32-bit MSB executable, PowerPC or cisco 4500, version 1 (SYSV), statically linked, stripped
165 test(s): 157 passed, 8 skipped, 0 failed => status: warning
nolibc-test: ELF 64-bit MSB executable, 64-bit PowerPC or cisco 7500, version 1 (SYSV), statically linked, stripped
165 test(s): 157 passed, 8 skipped, 0 failed => status: warning
nolibc-test: ELF 64-bit LSB executable, 64-bit PowerPC or cisco 7500, version 1 (SYSV), statically linked, stripped
Since the missing serial console enabling patch [1] for ppc32 has
already gotten a Reviewed-by line from the ppc maintainer, now, the ppc
defconfig aligns with the others', and it is able to simply move the
nolibc-test-config related stuff to the next tinyconfig series.
Based on v4 [2], beside removing several nolibc-test-config related
patches, two bugs with the latest gcc 13.1.0 have been fixed.
Changes from v4 --> v5:
* tools/nolibc: add support for powerpc64
selftests/nolibc: add XARCH and ARCH mapping support
selftests/nolibc: add test support for ppc64
selftests/nolibc: allow customize CROSS_COMPILE by architecture
selftests/nolibc: customize CROSS_COMPILE for 32/64-bit powerpc
Almost the same as v4.
* tools/nolibc: add support for powerpc
For 32-bit PowerPC, with newer gcc compilers (e.g. gcc 13.1.0),
"omit-frame-pointer" fails with __attribute__((no_stack_protector)) but
works with __attribute__((__optimize__("-fno-stack-protector")))
Using the later for ppc32 to workaround the issue.
* selftests/nolibc: add test support for ppc
Add default CFLAGS for ppc to allow build with the
latest powerpc64-linux-gcc toolchain from
https://mirrors.edge.kernel.org/pub/tools/crosstool/
* selftests/nolibc: add test support for ppc64le
Align with kernel, prefer elfv2 ABI to elfv1 ABI when the toolchain
support, otherwise, ABI mismatched binary will not run.
Best regards,
Zhangjin Wu
---
[1]: https://lore.kernel.org/lkml/bb7b5f9958b3e3a20f6573ff7ce7c5dc566e7e32.1690982937.git.tanyuan@tinylab.org/
[2]: https://lore.kernel.org/lkml/[email protected]/
Zhangjin Wu (8):
tools/nolibc: add support for powerpc
tools/nolibc: add support for powerpc64
selftests/nolibc: add XARCH and ARCH mapping support
selftests/nolibc: add test support for ppc
selftests/nolibc: add test support for ppc64le
selftests/nolibc: add test support for ppc64
selftests/nolibc: allow customize CROSS_COMPILE by architecture
selftests/nolibc: customize CROSS_COMPILE for 32/64-bit powerpc
tools/include/nolibc/arch-powerpc.h | 213 ++++++++++++++++++++++++
tools/include/nolibc/arch.h | 2 +
tools/testing/selftests/nolibc/Makefile | 74 ++++++--
3 files changed, 277 insertions(+), 12 deletions(-)
create mode 100644 tools/include/nolibc/arch-powerpc.h
--
2.25.1
Kernel uses ARCH=powerpc for both 32-bit and 64-bit PowerPC, here adds a
ppc64le variant for little endian 64-bit PowerPC, users can pass
XARCH=ppc64le to test it.
The powernv machine of qemu-system-ppc64le is used for there is just a
working powernv_defconfig.
As the document [1] shows:
PowerNV (as Non-Virtualized) is the “bare metal” platform using the
OPAL firmware. It runs Linux on IBM and OpenPOWER systems and it can be
used as an hypervisor OS, running KVM guests, or simply as a host OS.
Notes,
- since the VSX support may be disabled in kernel side, to avoid
"illegal instruction" errors due to missing VSX kernel support, let's
simply let compiler not generate vector/scalar (VSX) instructions via
the '-mno-vsx' option.
- little endian ppc64 prefers elfv2 to elfv1 if the toolchain (e.g. gcc
13.1.0) supports it, let's align with kernel, otherwise, our elfv1
binary will not run on kernel with elfv2 ABI.
[1]: https://qemu.readthedocs.io/en/latest/system/ppc/powernv.html
Suggested-by: Willy Tarreau <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Reviewed-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Zhangjin Wu <[email protected]>
---
tools/testing/selftests/nolibc/Makefile | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 53f55aad8f5c..4d71393e75ef 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -35,6 +35,7 @@ XARCH = $(or $(XARCH_$(ARCH)),$(ARCH))
# map from user input variants to their kernel supported architectures
ARCH_ppc = powerpc
+ARCH_ppc64le = powerpc
ARCH := $(or $(ARCH_$(XARCH)),$(XARCH))
# kernel image names by architecture
@@ -45,6 +46,7 @@ IMAGE_arm64 = arch/arm64/boot/Image
IMAGE_arm = arch/arm/boot/zImage
IMAGE_mips = vmlinuz
IMAGE_ppc = vmlinux
+IMAGE_ppc64le = arch/powerpc/boot/zImage
IMAGE_riscv = arch/riscv/boot/Image
IMAGE_s390 = arch/s390/boot/bzImage
IMAGE_loongarch = arch/loongarch/boot/vmlinuz.efi
@@ -59,6 +61,7 @@ DEFCONFIG_arm64 = defconfig
DEFCONFIG_arm = multi_v7_defconfig
DEFCONFIG_mips = malta_defconfig
DEFCONFIG_ppc = pmac32_defconfig
+DEFCONFIG_ppc64le = powernv_defconfig
DEFCONFIG_riscv = defconfig
DEFCONFIG_s390 = defconfig
DEFCONFIG_loongarch = defconfig
@@ -75,6 +78,7 @@ QEMU_ARCH_arm64 = aarch64
QEMU_ARCH_arm = arm
QEMU_ARCH_mips = mipsel # works with malta_defconfig
QEMU_ARCH_ppc = ppc
+QEMU_ARCH_ppc64le = ppc64le
QEMU_ARCH_riscv = riscv64
QEMU_ARCH_s390 = s390x
QEMU_ARCH_loongarch = loongarch64
@@ -88,6 +92,7 @@ QEMU_ARGS_arm64 = -M virt -cpu cortex-a53 -append "panic=-1 $(TEST:%=NOLIBC
QEMU_ARGS_arm = -M virt -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_mips = -M malta -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_ppc = -M g3beige -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
+QEMU_ARGS_ppc64le = -M powernv -append "console=hvc0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_riscv = -M virt -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_s390 = -M s390-ccw-virtio -m 1G -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_loongarch = -M virt -append "console=ttyS0,115200 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
@@ -104,6 +109,7 @@ Q=@
endif
CFLAGS_ppc = -m32 -mbig-endian -Wl,-EB,-melf32ppc -mmultiple -mno-vsx
+CFLAGS_ppc64le = -m64 -mlittle-endian -Wl,-EL,-melf64lppc -mno-vsx $(call cc-option,-mabi=elfv2)
CFLAGS_s390 = -m64
CFLAGS_mips = -EL
CFLAGS_STACKPROTECTOR ?= $(call cc-option,-mstack-protector-guard=global $(call cc-option,-fstack-protector-all))
--
2.25.1
Kernel uses ARCH=powerpc for both 32-bit and 64-bit PowerPC, here adds a
ppc64 variant for big endian 64-bit PowerPC, users can pass XARCH=ppc64
to test it.
The powernv machine of qemu-system-ppc64 is used with
powernv_be_defconfig.
As the document [1] shows:
PowerNV (as Non-Virtualized) is the “bare metal” platform using the
OPAL firmware. It runs Linux on IBM and OpenPOWER systems and it can be
used as an hypervisor OS, running KVM guests, or simply as a host OS.
Notes,
- differs from little endian 64-bit PowerPC, vmlinux is used instead of
zImage, because big endian zImage [2] only boot on qemu with x-vof=on
(added from qemu v7.0) and a fixup patch [3] for qemu v7.0.51:
- since the VSX support may be disabled in kernel side, to avoid
"illegal instruction" errors due to missing VSX kernel support, let's
simply let compiler not generate vector/scalar (VSX) instructions via
the '-mno-vsx' option.
- as 'man gcc' shows, '-mmultiple' is used to generate code that uses
the load multiple word instructions and the store multiple word
instructions. Those instructions do not work when the processor is in
little-endian mode (except PPC740/PPC750), so, we only enable it
for big endian powerpc.
- for big endian ppc64, as the help message from arch/powerpc/Kconfig
shows, the V2 ABI is standard for 64-bit little-endian, but for
big-endian it is less well tested by kernel and toolchain, so, use
elfv1 as-is, no need to explicitly ask toolchain to use elfv2 here.
[1]: https://qemu.readthedocs.io/en/latest/system/ppc/powernv.html
[2]: https://github.com/linuxppc/issues/issues/402
[3]: https://lore.kernel.org/qemu-devel/[email protected]/
Suggested-by: Willy Tarreau <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Link: https://lore.kernel.org/lkml/[email protected]/
Reviewed-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Zhangjin Wu <[email protected]>
---
tools/testing/selftests/nolibc/Makefile | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 4d71393e75ef..ec290cd82e21 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -35,6 +35,7 @@ XARCH = $(or $(XARCH_$(ARCH)),$(ARCH))
# map from user input variants to their kernel supported architectures
ARCH_ppc = powerpc
+ARCH_ppc64 = powerpc
ARCH_ppc64le = powerpc
ARCH := $(or $(ARCH_$(XARCH)),$(XARCH))
@@ -46,6 +47,7 @@ IMAGE_arm64 = arch/arm64/boot/Image
IMAGE_arm = arch/arm/boot/zImage
IMAGE_mips = vmlinuz
IMAGE_ppc = vmlinux
+IMAGE_ppc64 = vmlinux
IMAGE_ppc64le = arch/powerpc/boot/zImage
IMAGE_riscv = arch/riscv/boot/Image
IMAGE_s390 = arch/s390/boot/bzImage
@@ -61,6 +63,7 @@ DEFCONFIG_arm64 = defconfig
DEFCONFIG_arm = multi_v7_defconfig
DEFCONFIG_mips = malta_defconfig
DEFCONFIG_ppc = pmac32_defconfig
+DEFCONFIG_ppc64 = powernv_be_defconfig
DEFCONFIG_ppc64le = powernv_defconfig
DEFCONFIG_riscv = defconfig
DEFCONFIG_s390 = defconfig
@@ -78,6 +81,7 @@ QEMU_ARCH_arm64 = aarch64
QEMU_ARCH_arm = arm
QEMU_ARCH_mips = mipsel # works with malta_defconfig
QEMU_ARCH_ppc = ppc
+QEMU_ARCH_ppc64 = ppc64
QEMU_ARCH_ppc64le = ppc64le
QEMU_ARCH_riscv = riscv64
QEMU_ARCH_s390 = s390x
@@ -92,6 +96,7 @@ QEMU_ARGS_arm64 = -M virt -cpu cortex-a53 -append "panic=-1 $(TEST:%=NOLIBC
QEMU_ARGS_arm = -M virt -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_mips = -M malta -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_ppc = -M g3beige -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
+QEMU_ARGS_ppc64 = -M powernv -append "console=hvc0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_ppc64le = -M powernv -append "console=hvc0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_riscv = -M virt -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_s390 = -M s390-ccw-virtio -m 1G -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
@@ -109,6 +114,7 @@ Q=@
endif
CFLAGS_ppc = -m32 -mbig-endian -Wl,-EB,-melf32ppc -mmultiple -mno-vsx
+CFLAGS_ppc64 = -m64 -mbig-endian -Wl,-EB,-melf64ppc -mmultiple -mno-vsx
CFLAGS_ppc64le = -m64 -mlittle-endian -Wl,-EL,-melf64lppc -mno-vsx $(call cc-option,-mabi=elfv2)
CFLAGS_s390 = -m64
CFLAGS_mips = -EL
--
2.25.1
Some cross compilers may not just be prefixed with ARCH, customize them
by architecture may simplify the test a lot, especially, when iterate
with ARCH.
After customizing this for every architecture, the minimal test argument
will be architecture itself, no CROSS_COMPILE required to be passed.
If the prefix of installed cross compiler is not the same as the one
customized, we can also pass CROSS_COMPILE as before or even pass
CROSS_COMPILE_<ARCH>.
Signed-off-by: Zhangjin Wu <[email protected]>
---
tools/testing/selftests/nolibc/Makefile | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index ec290cd82e21..6e34d364a177 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -55,6 +55,12 @@ IMAGE_loongarch = arch/loongarch/boot/vmlinuz.efi
IMAGE = $(IMAGE_$(XARCH))
IMAGE_NAME = $(notdir $(IMAGE))
+# CROSS_COMPILE: cross toolchain prefix by architecture
+CROSS_COMPILE ?= $(CROSS_COMPILE_$(XARCH))
+
+# make sure CC is prefixed with CROSS_COMPILE
+$(call allow-override,CC,$(CROSS_COMPILE)gcc)
+
# default kernel configurations that appear to be usable
DEFCONFIG_i386 = defconfig
DEFCONFIG_x86_64 = defconfig
--
2.25.1
The little-endian powerpc64le compilers provided by Ubuntu and Fedora
are able to compile big endian kernel and big endian nolibc-test [1].
These default CROSS_COMPILE settings allow to test target architectures
with:
$ cd /path/to/tools/testing/selftests/nolibc/
$ for arch in ppc ppc64 ppc64le; do \
make run-user XARCH=$arch | grep "status: "; \
done
If want to use another cross compiler, please simply pass CROSS_COMPILE
or CC as before.
For example, it is able to build 64-bit nolibc-test with the big endian
powerpc64-linux-gcc crosstool from [2]:
$ wget -c https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/13.1.0/x86_64-gcc-13.1.0-nolibc-powerpc64-linux.tar.xz
$ tar xvf x86_64-gcc-13.1.0-nolibc-powerpc64-linux.tar.xz
$ export PATH=$PWD/gcc-13.1.0-nolibc/powerpc64-linux/bin/:$PATH
$ export CROSS_COMPILE_ppc=powerpc64-linux-
$ export CROSS_COMPILE_ppc64=powerpc64-linux-
$ export CROSS_COMPILE_ppc64le=powerpc64-linux-
$ for arch in ppc ppc64 ppc64le; do \
make run-user XARCH=$arch | grep "status: "; \
done
Or specify CC directly with full path:
$ export CC=$PWD/gcc-13.1.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc
$ for arch in ppc ppc64 ppc64le; do \
make run-user XARCH=$arch | grep "status: "; \
done
[1]: https://github.com/open-power/skiboot
[2]: https://mirrors.edge.kernel.org/pub/tools/crosstool/
Signed-off-by: Zhangjin Wu <[email protected]>
---
tools/testing/selftests/nolibc/Makefile | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 6e34d364a177..16cc33db54e3 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -56,6 +56,9 @@ IMAGE = $(IMAGE_$(XARCH))
IMAGE_NAME = $(notdir $(IMAGE))
# CROSS_COMPILE: cross toolchain prefix by architecture
+CROSS_COMPILE_ppc ?= powerpc-linux-gnu-
+CROSS_COMPILE_ppc64 ?= powerpc64le-linux-gnu-
+CROSS_COMPILE_ppc64le ?= powerpc64le-linux-gnu-
CROSS_COMPILE ?= $(CROSS_COMPILE_$(XARCH))
# make sure CC is prefixed with CROSS_COMPILE
--
2.25.1
This follows the 64-bit PowerPC ABI [1], refers to the slides: "A new
ABI for little-endian PowerPC64 Design & Implementation" [2] and the
musl code in arch/powerpc64/crt_arch.h.
First, stdu and clrrdi are used instead of stwu and clrrwi for
powerpc64.
Second, the stack frame size is increased to 32 bytes for powerpc64, 32
bytes is the minimal stack frame size supported described in [2].
Besides, the TOC pointer (GOT pointer) must be saved to r2.
This works on both little endian and big endian 64-bit PowerPC.
[1]: https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.pdf
[2]: https://www.llvm.org/devmtg/2014-04/PDFs/Talks/Euro-LLVM-2014-Weigand.pdf
Reviewed-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Zhangjin Wu <[email protected]>
---
tools/include/nolibc/arch-powerpc.h | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/tools/include/nolibc/arch-powerpc.h b/tools/include/nolibc/arch-powerpc.h
index 8332c9d3e5d6..76c3784f9dc7 100644
--- a/tools/include/nolibc/arch-powerpc.h
+++ b/tools/include/nolibc/arch-powerpc.h
@@ -172,6 +172,7 @@
_ret; \
})
+#ifndef __powerpc64__
/* FIXME: For 32-bit PowerPC, with newer gcc compilers (e.g. gcc 13.1.0),
* "omit-frame-pointer" fails with __attribute__((no_stack_protector)) but
* works with __attribute__((__optimize__("-fno-stack-protector")))
@@ -180,10 +181,24 @@
#undef __no_stack_protector
#define __no_stack_protector __attribute__((__optimize__("-fno-stack-protector")))
#endif
+#endif /* !__powerpc64__ */
/* startup code */
void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
{
+#ifdef __powerpc64__
+ /* On 64-bit PowerPC, save TOC/GOT pointer to r2 */
+ extern char TOC __asm__ (".TOC.");
+ register volatile long r2 __asm__ ("r2") = (void *)&TOC - (void *)_start;
+
+ __asm__ volatile (
+ "mr 3, 1\n" /* save stack pointer to r3, as arg1 of _start_c */
+ "clrrdi 1, 1, 4\n" /* align the stack to 16 bytes */
+ "li 0, 0\n" /* zero the frame pointer */
+ "stdu 1, -32(1)\n" /* the initial stack frame */
+ "bl _start_c\n" /* transfer to c runtime */
+ );
+#else
__asm__ volatile (
"mr 3, 1\n" /* save stack pointer to r3, as arg1 of _start_c */
"clrrwi 1, 1, 4\n" /* align the stack to 16 bytes */
@@ -191,6 +206,7 @@ void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_
"stwu 1, -16(1)\n" /* the initial stack frame */
"bl _start_c\n" /* transfer to c runtime */
);
+#endif
__builtin_unreachable();
}
--
2.25.1
Both syscall declarations and _start code definition are added for
powerpc to nolibc.
Like mips, powerpc uses a register (exactly, the summary overflow bit)
to record the error occurred, and uses another register to return the
value [1]. So, the return value of every syscall declaration must be
normalized to match the __sysret() helper, return -value when there is
an error, otheriwse, return value directly.
Glibc and musl use different methods to check the summary overflow bit,
glibc (sysdeps/unix/sysv/linux/powerpc/sysdep.h) saves the cr register
to r0 at first, and then check the summary overflow bit in cr0:
mfcr r0
r0 & (1 << 28) ? -r3 : r3
-->
10003c14: 7c 00 00 26 mfcr r0
10003c18: 74 09 10 00 andis. r9,r0,4096
10003c1c: 41 82 00 08 beq 0x10003c24
10003c20: 7c 63 00 d0 neg r3,r3
Musl (arch/powerpc/syscall_arch.h) directly checks the summary overflow
bit with the 'bns' instruction, it is smaller:
/* no summary overflow bit means no error, return value directly */
bns+ 1f
/* otherwise, return negated value */
neg r3, r3
1:
-->
10000418: 40 a3 00 08 bns 0x10000420
1000041c: 7c 63 00 d0 neg r3,r3
Like musl, Linux (arch/powerpc/include/asm/vdso/gettimeofday.h) uses the
same method for do_syscall_2() too.
Here applies the second method to get smaller size.
[1]: https://man7.org/linux/man-pages/man2/syscall.2.html
Reviewed-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Zhangjin Wu <[email protected]>
---
tools/include/nolibc/arch-powerpc.h | 197 ++++++++++++++++++++++++++++
tools/include/nolibc/arch.h | 2 +
2 files changed, 199 insertions(+)
create mode 100644 tools/include/nolibc/arch-powerpc.h
diff --git a/tools/include/nolibc/arch-powerpc.h b/tools/include/nolibc/arch-powerpc.h
new file mode 100644
index 000000000000..8332c9d3e5d6
--- /dev/null
+++ b/tools/include/nolibc/arch-powerpc.h
@@ -0,0 +1,197 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * PowerPC specific definitions for NOLIBC
+ * Copyright (C) 2023 Zhangjin Wu <[email protected]>
+ */
+
+#ifndef _NOLIBC_ARCH_POWERPC_H
+#define _NOLIBC_ARCH_POWERPC_H
+
+#include "compiler.h"
+#include "crt.h"
+
+/* Syscalls for PowerPC :
+ * - stack is 16-byte aligned
+ * - syscall number is passed in r0
+ * - arguments are in r3, r4, r5, r6, r7, r8, r9
+ * - the system call is performed by calling "sc"
+ * - syscall return comes in r3, and the summary overflow bit is checked
+ * to know if an error occurred, in which case errno is in r3.
+ * - the arguments are cast to long and assigned into the target
+ * registers which are then simply passed as registers to the asm code,
+ * so that we don't have to experience issues with register constraints.
+ */
+
+#define _NOLIBC_SYSCALL_CLOBBERLIST \
+ "memory", "cr0", "r12", "r11", "r10", "r9"
+
+#define my_syscall0(num) \
+({ \
+ register long _ret __asm__ ("r3"); \
+ register long _num __asm__ ("r0") = (num); \
+ \
+ __asm__ volatile ( \
+ " sc\n" \
+ " bns+ 1f\n" \
+ " neg %0, %0\n" \
+ "1:\n" \
+ : "=r"(_ret), "+r"(_num) \
+ : \
+ : _NOLIBC_SYSCALL_CLOBBERLIST, "r8", "r7", "r6", "r5", "r4" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall1(num, arg1) \
+({ \
+ register long _ret __asm__ ("r3"); \
+ register long _num __asm__ ("r0") = (num); \
+ register long _arg1 __asm__ ("r3") = (long)(arg1); \
+ \
+ __asm__ volatile ( \
+ " sc\n" \
+ " bns+ 1f\n" \
+ " neg %0, %0\n" \
+ "1:\n" \
+ : "=r"(_ret), "+r"(_num) \
+ : "0"(_arg1) \
+ : _NOLIBC_SYSCALL_CLOBBERLIST, "r8", "r7", "r6", "r5", "r4" \
+ ); \
+ _ret; \
+})
+
+
+#define my_syscall2(num, arg1, arg2) \
+({ \
+ register long _ret __asm__ ("r3"); \
+ register long _num __asm__ ("r0") = (num); \
+ register long _arg1 __asm__ ("r3") = (long)(arg1); \
+ register long _arg2 __asm__ ("r4") = (long)(arg2); \
+ \
+ __asm__ volatile ( \
+ " sc\n" \
+ " bns+ 1f\n" \
+ " neg %0, %0\n" \
+ "1:\n" \
+ : "=r"(_ret), "+r"(_num), "+r"(_arg2) \
+ : "0"(_arg1) \
+ : _NOLIBC_SYSCALL_CLOBBERLIST, "r8", "r7", "r6", "r5" \
+ ); \
+ _ret; \
+})
+
+
+#define my_syscall3(num, arg1, arg2, arg3) \
+({ \
+ register long _ret __asm__ ("r3"); \
+ register long _num __asm__ ("r0") = (num); \
+ register long _arg1 __asm__ ("r3") = (long)(arg1); \
+ register long _arg2 __asm__ ("r4") = (long)(arg2); \
+ register long _arg3 __asm__ ("r5") = (long)(arg3); \
+ \
+ __asm__ volatile ( \
+ " sc\n" \
+ " bns+ 1f\n" \
+ " neg %0, %0\n" \
+ "1:\n" \
+ : "=r"(_ret), "+r"(_num), "+r"(_arg2), "+r"(_arg3) \
+ : "0"(_arg1) \
+ : _NOLIBC_SYSCALL_CLOBBERLIST, "r8", "r7", "r6" \
+ ); \
+ _ret; \
+})
+
+
+#define my_syscall4(num, arg1, arg2, arg3, arg4) \
+({ \
+ register long _ret __asm__ ("r3"); \
+ register long _num __asm__ ("r0") = (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 ( \
+ " sc\n" \
+ " bns+ 1f\n" \
+ " neg %0, %0\n" \
+ "1:\n" \
+ : "=r"(_ret), "+r"(_num), "+r"(_arg2), "+r"(_arg3), \
+ "+r"(_arg4) \
+ : "0"(_arg1) \
+ : _NOLIBC_SYSCALL_CLOBBERLIST, "r8", "r7" \
+ ); \
+ _ret; \
+})
+
+
+#define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \
+({ \
+ register long _ret __asm__ ("r3"); \
+ register long _num __asm__ ("r0") = (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 ( \
+ " sc\n" \
+ " bns+ 1f\n" \
+ " neg %0, %0\n" \
+ "1:\n" \
+ : "=r"(_ret), "+r"(_num), "+r"(_arg2), "+r"(_arg3), \
+ "+r"(_arg4), "+r"(_arg5) \
+ : "0"(_arg1) \
+ : _NOLIBC_SYSCALL_CLOBBERLIST, "r8" \
+ ); \
+ _ret; \
+})
+
+#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \
+({ \
+ register long _ret __asm__ ("r3"); \
+ register long _num __asm__ ("r0") = (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 ( \
+ " sc\n" \
+ " bns+ 1f\n" \
+ " neg %0, %0\n" \
+ "1:\n" \
+ : "=r"(_ret), "+r"(_num), "+r"(_arg2), "+r"(_arg3), \
+ "+r"(_arg4), "+r"(_arg5), "+r"(_arg6) \
+ : "0"(_arg1) \
+ : _NOLIBC_SYSCALL_CLOBBERLIST \
+ ); \
+ _ret; \
+})
+
+/* FIXME: For 32-bit PowerPC, with newer gcc compilers (e.g. gcc 13.1.0),
+ * "omit-frame-pointer" fails with __attribute__((no_stack_protector)) but
+ * works with __attribute__((__optimize__("-fno-stack-protector")))
+ */
+#ifdef __no_stack_protector
+#undef __no_stack_protector
+#define __no_stack_protector __attribute__((__optimize__("-fno-stack-protector")))
+#endif
+
+/* startup code */
+void __attribute__((weak, noreturn, optimize("Os", "omit-frame-pointer"))) __no_stack_protector _start(void)
+{
+ __asm__ volatile (
+ "mr 3, 1\n" /* save stack pointer to r3, as arg1 of _start_c */
+ "clrrwi 1, 1, 4\n" /* align the stack to 16 bytes */
+ "li 0, 0\n" /* zero the frame pointer */
+ "stwu 1, -16(1)\n" /* the initial stack frame */
+ "bl _start_c\n" /* transfer to c runtime */
+ );
+ __builtin_unreachable();
+}
+
+#endif /* _NOLIBC_ARCH_POWERPC_H */
diff --git a/tools/include/nolibc/arch.h b/tools/include/nolibc/arch.h
index 82b43935650f..e276fb0680af 100644
--- a/tools/include/nolibc/arch.h
+++ b/tools/include/nolibc/arch.h
@@ -25,6 +25,8 @@
#include "arch-aarch64.h"
#elif defined(__mips__) && defined(_ABIO32)
#include "arch-mips.h"
+#elif defined(__powerpc__)
+#include "arch-powerpc.h"
#elif defined(__riscv)
#include "arch-riscv.h"
#elif defined(__s390x__)
--
2.25.1
Kernel uses ARCH=powerpc for both 32-bit and 64-bit PowerPC, here adds a
ppc variant for 32-bit PowerPC and uses it as the default variant of
powerpc architecture.
Users can pass XARCH=ppc (or ARCH=powerpc) to test 32-bit PowerPC.
The default qemu-system-ppc g3beige machine [1] is used to run 32-bit
powerpc kernel with pmac32_defconfig. The missing PMACZILOG serial tty
and console are enabled in another patch [2].
Note,
- zImage doesn't boot due to "qemu-system-ppc: Some ROM regions are
overlapping" error, so, vmlinux is used instead.
- since the VSX support may be disabled in kernel side, to avoid
"illegal instruction" errors due to missing VSX kernel support, let's
simply let compiler not generate vector/scalar (VSX) instructions via
the '-mno-vsx' option.
- as 'man gcc' shows, '-mmultiple' is used to generate code that uses
the load multiple word instructions and the store multiple word
instructions. Those instructions do not work when the processor is in
little-endian mode (except PPC740/PPC750), so, we only enable it
for big endian powerpc.
[1]: https://qemu.readthedocs.io/en/latest/system/ppc/powermac.html
[2]: https://lore.kernel.org/lkml/bb7b5f9958b3e3a20f6573ff7ce7c5dc566e7e32.1690982937.git.tanyuan@tinylab.org/
Suggested-by: Willy Tarreau <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Reviewed-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Zhangjin Wu <[email protected]>
---
tools/testing/selftests/nolibc/Makefile | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 46a2312b06f5..53f55aad8f5c 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -30,9 +30,11 @@ endif
# architectures where both are equal.
# configure default variants for target kernel supported architectures
+XARCH_powerpc = ppc
XARCH = $(or $(XARCH_$(ARCH)),$(ARCH))
# map from user input variants to their kernel supported architectures
+ARCH_ppc = powerpc
ARCH := $(or $(ARCH_$(XARCH)),$(XARCH))
# kernel image names by architecture
@@ -42,6 +44,7 @@ IMAGE_x86 = arch/x86/boot/bzImage
IMAGE_arm64 = arch/arm64/boot/Image
IMAGE_arm = arch/arm/boot/zImage
IMAGE_mips = vmlinuz
+IMAGE_ppc = vmlinux
IMAGE_riscv = arch/riscv/boot/Image
IMAGE_s390 = arch/s390/boot/bzImage
IMAGE_loongarch = arch/loongarch/boot/vmlinuz.efi
@@ -55,6 +58,7 @@ DEFCONFIG_x86 = defconfig
DEFCONFIG_arm64 = defconfig
DEFCONFIG_arm = multi_v7_defconfig
DEFCONFIG_mips = malta_defconfig
+DEFCONFIG_ppc = pmac32_defconfig
DEFCONFIG_riscv = defconfig
DEFCONFIG_s390 = defconfig
DEFCONFIG_loongarch = defconfig
@@ -70,6 +74,7 @@ QEMU_ARCH_x86 = x86_64
QEMU_ARCH_arm64 = aarch64
QEMU_ARCH_arm = arm
QEMU_ARCH_mips = mipsel # works with malta_defconfig
+QEMU_ARCH_ppc = ppc
QEMU_ARCH_riscv = riscv64
QEMU_ARCH_s390 = s390x
QEMU_ARCH_loongarch = loongarch64
@@ -82,6 +87,7 @@ QEMU_ARGS_x86 = -M pc -append "console=ttyS0,9600 i8042.noaux panic=-1 $(
QEMU_ARGS_arm64 = -M virt -cpu cortex-a53 -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_arm = -M virt -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_mips = -M malta -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
+QEMU_ARGS_ppc = -M g3beige -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_riscv = -M virt -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_s390 = -M s390-ccw-virtio -m 1G -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
QEMU_ARGS_loongarch = -M virt -append "console=ttyS0,115200 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
@@ -97,6 +103,7 @@ else
Q=@
endif
+CFLAGS_ppc = -m32 -mbig-endian -Wl,-EB,-melf32ppc -mmultiple -mno-vsx
CFLAGS_s390 = -m64
CFLAGS_mips = -EL
CFLAGS_STACKPROTECTOR ?= $(call cc-option,-mstack-protector-guard=global $(call cc-option,-fstack-protector-all))
--
2.25.1