[PATCH v3 0/3] Define CPU_BIG_ENDIAN or warn for inconsistencies

From: Babu Moger
Date: Thu Jul 06 2017 - 12:36:13 EST

Resending the series per Greg KH's request.

Found this problem while enabling queued rwlock on SPARC.
The parameter CONFIG_CPU_BIG_ENDIAN is used to clear the
specific byte in qrwlock structure. Without this parameter,
we clear the wrong byte.
Here is the code in include/asm-generic/qrwlock.h

static inline u8 *__qrwlock_write_byte(struct qrwlock *lock)
return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);

Also found few more references of this parameter in

Here is our previous discussion.

Based on the discussion, it was decided to add CONFIG_CPU_BIG_ENDIAN
for all the fixed big endian architecture(frv, h8300, m68k, openrisc,
parisc and sparc). And warn if there are inconsistencies in this definition.

v2 -> v3:
Added the choice statement for endianness selection for microblaze.
Updated the Makefile for microblaze(Suggested by Arnd Bergmann) to
properly compile for the correct format.
Updated acks.

v1 -> v2:
Updated the commit messages and acks.

Babu Moger (3):
arch: Define CPU_BIG_ENDIAN for all fixed big endian archs
arch/microblaze: Add choice for endianness and update Makefile
include: warn for inconsistent endian config definition

arch/frv/Kconfig | 3 +++
arch/h8300/Kconfig | 3 +++
arch/m68k/Kconfig | 3 +++
arch/microblaze/Kconfig | 16 ++++++++++++++++
arch/microblaze/Makefile | 2 ++
arch/openrisc/Kconfig | 3 +++
arch/parisc/Kconfig | 3 +++
arch/sparc/Kconfig | 3 +++
include/linux/byteorder/big_endian.h | 4 ++++
include/linux/byteorder/little_endian.h | 4 ++++
10 files changed, 44 insertions(+), 0 deletions(-)