From 6672aebfe46c2ce8fa61f1ad9919e0ea570b3a9d Mon Sep 17 00:00:00 2001
From: Jeffrey Pfau <jeffrey@endrift.com>
Date: Tue, 30 Sep 2014 10:08:43 +0000
Subject: [PATCH] Proper endian swapping on older PPC ISAs

---
 src/arm/common.h | 43 ++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 38 insertions(+), 5 deletions(-)

diff --git a/src/arm/common.h b/src/arm/common.h
index ff13735c1..a1d42d1dc 100644
--- a/src/arm/common.h
+++ b/src/arm/common.h
@@ -16,11 +16,44 @@
 
 #define UNUSED(V) (void)(V)
 
-#ifdef __POWERPC__
-#define LOAD_32(DEST, ADDR, ARR) asm("lwbrx %0, %1, %2" : "=r"(DEST) : "r"(ADDR), "r"(ARR))
-#define LOAD_16(DEST, ADDR, ARR) asm("lhbrx %0, %1, %2" : "=r"(DEST) : "r"(ADDR), "r"(ARR))
-#define STORE_32(SRC, ADDR, ARR) asm("stwbrx %0, %1, %2" : : "r"(SRC), "r"(ADDR), "r"(ARR))
-#define STORE_16(SRC, ADDR, ARR) asm("sthbrx %0, %1, %2" : : "r"(SRC), "r"(ADDR), "r"(ARR))
+#ifdef __BIG_ENDIAN__
+
+#if defined(__PPC__) || defined(__POWERPC__)
+#define SWAP_32(DEST, VAR) asm(\
+	"rlwinm %0, %1, 8, 24, 31\n" \
+	"rlwimi %0, %1, 24, 16, 23\n" \
+	"rlwimi %0, %1, 8, 8, 15\n" \
+	"rlwimi %0, %1, 24, 0, 7\n" \
+	: "+r"(DEST) : "r"(VAR) : )
+
+#define SWAP_16(DEST, VAR) asm(\
+	"rlwinm %0, %1, 24, 24, 31\n" \
+	"rlwimi %0, %1, 8, 16, 23\n" \
+	: "+r"(DEST) : "r"(VAR) : )
+#endif
+
+#define LOAD_32(DEST, ADDR, ARR) { \
+	uint32_t _tmp = ((uint32_t*) ARR)[(ADDR) >> 2]; \
+	SWAP_32(DEST, _tmp); \
+}
+
+#define LOAD_16(DEST, ADDR, ARR) { \
+	uint16_t _tmp = ((uint16_t*) ARR)[(ADDR) >> 1]; \
+	SWAP_16(DEST, _tmp); \
+}
+
+#define STORE_32(SRC, ADDR, ARR) { \
+	uint32_t _tmp; \
+	SWAP_32(_tmp, SRC); \
+	((uint32_t*) ARR)[(ADDR) >> 2] = _tmp; \
+}
+
+#define STORE_16(SRC, ADDR, ARR) { \
+	uint16_t _tmp; \
+	SWAP_16(_tmp, SRC); \
+	((uint16_t*) ARR)[(ADDR) >> 2] = _tmp; \
+}
+
 #else
 #define LOAD_32(DEST, ADDR, ARR) DEST = ((uint32_t*) ARR)[(ADDR) >> 2]
 #define LOAD_16(DEST, ADDR, ARR) DEST = ((uint16_t*) ARR)[(ADDR) >> 1]