Re: [PATCH v2 13/20] tests/tcg: enable basic testing for aarch64_be-linux-user

[Pierrick Bouvier <pierrick.bouvier@linaro.org>]

On 10/22/24 03:56, Alex Bennée wrote:
> We didn't notice breakage of aarch64_be because we don't have any TCG
> tests for it. However while the existing aarch64 compiler can target
> big-endian builds no one packages a BE libc. Instead we bang some
> rocks together to do the most basic of hello world with a nostdlib
> syscall test.
> 
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> 
> ---
> v2
>    - fix checkpatch complaints
> ---
>   configure                            |  5 ++++
>   tests/tcg/aarch64_be/hello.c         | 35 ++++++++++++++++++++++++++++
>   tests/tcg/Makefile.target            |  7 +++++-
>   tests/tcg/aarch64_be/Makefile.target | 17 ++++++++++++++
>   4 files changed, 63 insertions(+), 1 deletion(-)
>   create mode 100644 tests/tcg/aarch64_be/hello.c
>   create mode 100644 tests/tcg/aarch64_be/Makefile.target
> 
> diff --git a/configure b/configure
> index 72d1a94225..7dd3400ccb 100755
> --- a/configure
> +++ b/configure
> @@ -1418,6 +1418,7 @@ probe_target_compiler() {
>     target_arch=${1%%-*}
>     case $target_arch in
>       aarch64) container_hosts="x86_64 aarch64" ;;
> +    aarch64_be) container_hosts="x86_64 aarch64" ;;
>       alpha) container_hosts=x86_64 ;;
>       arm) container_hosts="x86_64 aarch64" ;;
>       hexagon) container_hosts=x86_64 ;;
> @@ -1447,6 +1448,10 @@ probe_target_compiler() {
>       case $target_arch in
>         # debian-all-test-cross architectures
>   
> +      aarch64_be)
> +        container_image=debian-all-test-cross
> +        container_cross_prefix=aarch64-linux-gnu-
> +        ;;
>         hppa|m68k|mips|riscv64|sparc64)
>           container_image=debian-all-test-cross
>           ;;
> diff --git a/tests/tcg/aarch64_be/hello.c b/tests/tcg/aarch64_be/hello.c
> new file mode 100644
> index 0000000000..a9b2ab45de
> --- /dev/null
> +++ b/tests/tcg/aarch64_be/hello.c
> @@ -0,0 +1,35 @@
> +/*
> + * Non-libc syscall hello world for Aarch64 BE
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#define __NR_write 64
> +#define __NR_exit 93
> +
> +int write(int fd, char *buf, int len)
> +{
> +    register int x0 __asm__("x0") = fd;
> +    register char *x1 __asm__("x1") = buf;
> +    register int x2 __asm__("x2") = len;
> +    register int x8 __asm__("x8") = __NR_write;
> +
> +    asm volatile("svc #0" : : "r"(x0), "r"(x1), "r"(x2), "r"(x8));
> +
> +    return len;
> +}
> +
> +void exit(int ret)
> +{
> +    register int x0 __asm__("x0") = ret;
> +    register int x8 __asm__("x8") = __NR_exit;
> +
> +    asm volatile("svc #0" : : "r"(x0), "r"(x8));
> +    __builtin_unreachable();
> +}
> +
> +void _start(void)
> +{
> +    write(1, "Hello World\n", 12);
> +    exit(0);
> +}
> diff --git a/tests/tcg/Makefile.target b/tests/tcg/Makefile.target
> index 2da70b2fcf..9722145b97 100644
> --- a/tests/tcg/Makefile.target
> +++ b/tests/tcg/Makefile.target
> @@ -103,9 +103,14 @@ ifeq ($(filter %-softmmu, $(TARGET)),)
>   # then the target. If there are common tests shared between
>   # sub-targets (e.g. ARM & AArch64) then it is up to
>   # $(TARGET_NAME)/Makefile.target to include the common parent
> -# architecture in its VPATH.
> +# architecture in its VPATH. However some targets are so minimal we
> +# can't even build the multiarch tests.
> +ifneq ($(filter $(TARGET_NAME),aarch64_be),)
> +-include $(SRC_PATH)/tests/tcg/$(TARGET_NAME)/Makefile.target
> +else
>   -include $(SRC_PATH)/tests/tcg/multiarch/Makefile.target
>   -include $(SRC_PATH)/tests/tcg/$(TARGET_NAME)/Makefile.target
> +endif
>   
>   # Add the common build options
>   CFLAGS+=-Wall -Werror -O0 -g -fno-strict-aliasing
> diff --git a/tests/tcg/aarch64_be/Makefile.target b/tests/tcg/aarch64_be/Makefile.target
> new file mode 100644
> index 0000000000..297d2cf71c
> --- /dev/null
> +++ b/tests/tcg/aarch64_be/Makefile.target
> @@ -0,0 +1,17 @@
> +# -*- Mode: makefile -*-
> +#
> +# A super basic AArch64 BE makefile. As we don't have any big-endian
> +#l ibc available the best we can do is a basic Hello World.
> +

s/l ibc/ libc/

> +AARCH64BE_SRC=$(SRC_PATH)/tests/tcg/aarch64_be
> +VPATH += $(AARCH64BE_SRC)
> +
> +AARCH64BE_TEST_SRCS=$(notdir $(wildcard $(AARCH64BE_SRC)/*.c))
> +AARCH64BE_TESTS=$(AARCH64BE_TEST_SRCS:.c=)
> +#MULTIARCH_TESTS = $(MULTIARCH_SRCS:.c=)
> +
> +# We need to specify big-endian cflags
> +CFLAGS +=-mbig-endian -ffreestanding
> +LDFLAGS +=-nostdlib
> +
> +TESTS += $(AARCH64BE_TESTS)

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>