From: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Subject: powerpc: Use generic checksum code in little endian
Git-commit: 7a332b0c9a59e0b0777dec55eefdda0f9a24ac52
Patch-mainline: v3.13-rc1
References: bnc#856774 fate#315275, LTC#92305

Summary:     powerpc: add little-endian support
Description: Add little-endian support for POWER8.

Upstream-Description:

    powerpc: Use generic checksum code in little endian

    We need to fix some endian issues in our checksum code. For now
    just enable the generic checksum routines for little endian builds.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Acked-by: Torsten Duwe <duwe@suse.de>
---
 arch/powerpc/Kconfig                |    3 +++
 arch/powerpc/include/asm/checksum.h |    5 +++++
 arch/powerpc/kernel/ppc_ksyms.c     |    2 ++
 arch/powerpc/lib/Makefile           |    9 +++++++--
 4 files changed, 17 insertions(+), 2 deletions(-)

--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -140,6 +140,9 @@ config PPC
 	select HAVE_DEBUG_STACKOVERFLOW
 	select ARCH_SUPPORTS_ATOMIC_RMW
 
+config GENERIC_CSUM
+	def_bool CPU_LITTLE_ENDIAN
+
 config EARLY_PRINTK
 	bool
 	default y
--- a/arch/powerpc/include/asm/checksum.h
+++ b/arch/powerpc/include/asm/checksum.h
@@ -14,6 +14,9 @@
  * which always checksum on 4 octet boundaries.  ihl is the number
  * of 32-bit words and is always >= 5.
  */
+#ifdef CONFIG_GENERIC_CSUM
+#include <asm-generic/checksum.h>
+#else
 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
 
 /*
@@ -123,5 +126,7 @@ static inline __wsum csum_tcpudp_nofold(
 	return sum;
 #endif
 }
+
+#endif
 #endif /* __KERNEL__ */
 #endif
--- a/arch/powerpc/kernel/ppc_ksyms.c
+++ b/arch/powerpc/kernel/ppc_ksyms.c
@@ -79,10 +79,12 @@ EXPORT_SYMBOL(strlen);
 EXPORT_SYMBOL(strcmp);
 EXPORT_SYMBOL(strncmp);
 
+#ifndef CONFIG_GENERIC_CSUM
 EXPORT_SYMBOL(csum_partial);
 EXPORT_SYMBOL(csum_partial_copy_generic);
 EXPORT_SYMBOL(ip_fast_csum);
 EXPORT_SYMBOL(csum_tcpudp_magic);
+#endif
 
 EXPORT_SYMBOL(__copy_tofrom_user);
 EXPORT_SYMBOL(__clear_user);
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -10,15 +10,20 @@ CFLAGS_REMOVE_code-patching.o = -pg
 CFLAGS_REMOVE_feature-fixups.o = -pg
 
 obj-y			:= string.o alloc.o \
-			   checksum_$(CONFIG_WORD_SIZE).o crtsavres.o
+			   crtsavres.o
 obj-$(CONFIG_PPC32)	+= div64.o copy_32.o
 obj-$(CONFIG_HAS_IOMEM)	+= devres.o
 
 obj-$(CONFIG_PPC64)	+= copypage_64.o copyuser_64.o \
 			   memcpy_64.o usercopy_64.o mem_64.o string.o \
-			   checksum_wrappers_64.o hweight_64.o \
+			   hweight_64.o \
 			   copyuser_power7.o string_64.o copypage_power7.o \
 			   memcpy_power7.o
+ifeq ($(CONFIG_GENERIC_CSUM),)
+obj-y			+= checksum_$(CONFIG_WORD_SIZE).o
+obj-$(CONFIG_PPC64)	+= checksum_wrappers_64.o
+endif
+
 obj-$(CONFIG_PPC_EMULATE_SSTEP)	+= sstep.o ldstfp.o
 
 ifeq ($(CONFIG_PPC64),y)
