Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751836AbdFITt6 (ORCPT ); Fri, 9 Jun 2017 15:49:58 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:41536 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751639AbdFITtz (ORCPT ); Fri, 9 Jun 2017 15:49:55 -0400 From: Babu Moger To: ysato@users.sourceforge.jp, geert@linux-m68k.org, jonas@southpole.se, stefan.kristiansson@saunalahti.fi, shorne@gmail.com, jejb@parisc-linux.org, deller@gmx.de, davem@davemloft.net, viro@zeniv.linux.org.uk Cc: mpe@ellerman.id.au, peterz@infradead.org, mingo@redhat.com, jcmvbkbc@gmail.com, linux-kernel@vger.kernel.org, uclinux-h8-devel@lists.sourceforge.jp, linux-m68k@vger.kernel.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org Subject: [PATCH v2 1/2] arch: Define CPU_BIG_ENDIAN for all fixed big endian archs Date: Fri, 9 Jun 2017 12:48:06 -0700 Message-Id: <1497037687-107638-2-git-send-email-babu.moger@oracle.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1497037687-107638-1-git-send-email-babu.moger@oracle.com> References: <1497037687-107638-1-git-send-email-babu.moger@oracle.com> X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3165 Lines: 124 While working on enabling queued rwlock on SPARC, found this following code in include/asm-generic/qrwlock.h which uses CONFIG_CPU_BIG_ENDIAN to clear a byte. static inline u8 *__qrwlock_write_byte(struct qrwlock *lock) { return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN); } Problem is many of the fixed big endian architectures don't define CPU_BIG_ENDIAN and clears the wrong byte. Define CPU_BIG_ENDIAN for all the fixed big endian architecture to fix it. Also found few more references of this config parameter in drivers/of/base.c drivers/of/fdt.c drivers/tty/serial/earlycon.c drivers/tty/serial/serial_core.c Be aware that this may cause regressions if someone has worked-around problems in the above code already. Remove the work-around. Here is our original discussion https://lkml.org/lkml/2017/5/24/620 Signed-off-by: Babu Moger Suggested-by: Arnd Bergmann Acked-by: Geert Uytterhoeven Acked-by: David S. Miller --- arch/frv/Kconfig | 3 +++ arch/h8300/Kconfig | 3 +++ arch/m68k/Kconfig | 3 +++ arch/openrisc/Kconfig | 3 +++ arch/parisc/Kconfig | 3 +++ arch/sparc/Kconfig | 3 +++ 6 files changed, 18 insertions(+), 0 deletions(-) diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig index eefd9a4..1cce824 100644 --- a/arch/frv/Kconfig +++ b/arch/frv/Kconfig @@ -17,6 +17,9 @@ config FRV select HAVE_DEBUG_STACKOVERFLOW select ARCH_NO_COHERENT_DMA_MMAP +config CPU_BIG_ENDIAN + def_bool y + config ZONE_DMA bool default y diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index 3ae8525..5380ac8 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -23,6 +23,9 @@ config H8300 select HAVE_ARCH_HASH select CPU_NO_EFFICIENT_FFS +config CPU_BIG_ENDIAN + def_bool y + config RWSEM_GENERIC_SPINLOCK def_bool y diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index d140206..029a58b 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -23,6 +23,9 @@ config M68K select OLD_SIGSUSPEND3 select OLD_SIGACTION +config CPU_BIG_ENDIAN + def_bool y + config RWSEM_GENERIC_SPINLOCK bool default y diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig index 1e95920..a0f2e4a 100644 --- a/arch/openrisc/Kconfig +++ b/arch/openrisc/Kconfig @@ -29,6 +29,9 @@ config OPENRISC select CPU_NO_EFFICIENT_FFS if !OPENRISC_HAVE_INST_FF1 select NO_BOOTMEM +config CPU_BIG_ENDIAN + def_bool y + config MMU def_bool y diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 531da9e..dda1f55 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -47,6 +47,9 @@ config PARISC and later HP3000 series). The PA-RISC Linux project home page is at . +config CPU_BIG_ENDIAN + def_bool y + config MMU def_bool y diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 58243b0..eb213b5 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -92,6 +92,9 @@ config ARCH_DEFCONFIG config ARCH_PROC_KCORE_TEXT def_bool y +config CPU_BIG_ENDIAN + def_bool y + config ARCH_ATU bool default y if SPARC64 -- 1.7.1