We have seen some generic code use config parameter CONFIG_CPU_BIG_ENDIAN to decide the endianness.
Here are the few examples. include/asm-generic/qrwlock.h drivers/of/base.c drivers/of/fdt.c drivers/tty/serial/earlycon.c drivers/tty/serial/serial_core.c Display warning if CPU_BIG_ENDIAN is not defined on big endian architecture and also warn if it defined on little endian architectures. Here is our original discussion https://lkml.org/lkml/2017/5/24/620 Signed-off-by: Babu Moger <babu.mo...@oracle.com> Suggested-by: Arnd Bergmann <a...@arndb.de> Acked-by: Geert Uytterhoeven <ge...@linux-m68k.org> --- include/linux/byteorder/big_endian.h | 4 ++++ include/linux/byteorder/little_endian.h | 4 ++++ 2 files changed, 8 insertions(+), 0 deletions(-) diff --git a/include/linux/byteorder/big_endian.h b/include/linux/byteorder/big_endian.h index 3920414..ffd2159 100644 --- a/include/linux/byteorder/big_endian.h +++ b/include/linux/byteorder/big_endian.h @@ -3,5 +3,9 @@ #include <uapi/linux/byteorder/big_endian.h> +#ifndef CONFIG_CPU_BIG_ENDIAN +#warning inconsistent configuration, needs CONFIG_CPU_BIG_ENDIAN +#endif + #include <linux/byteorder/generic.h> #endif /* _LINUX_BYTEORDER_BIG_ENDIAN_H */ diff --git a/include/linux/byteorder/little_endian.h b/include/linux/byteorder/little_endian.h index 0805737..ba910bb 100644 --- a/include/linux/byteorder/little_endian.h +++ b/include/linux/byteorder/little_endian.h @@ -3,5 +3,9 @@ #include <uapi/linux/byteorder/little_endian.h> +#ifdef CONFIG_CPU_BIG_ENDIAN +#warning inconsistent configuration, CONFIG_CPU_BIG_ENDIAN is set +#endif + #include <linux/byteorder/generic.h> #endif /* _LINUX_BYTEORDER_LITTLE_ENDIAN_H */ -- 1.7.1