[U-Boot] [PATCH v4 2/4]: arm: Make arm bitops endianness-independent

[Simon Kagstrom]

arm: Make arm bitops endianness-independent

Bring over the bitop implementations from the Linux
include/asm-generic/bitops/non-atomic.h to provide
endianness-independence.

Signed-off-by: Simon Kagstrom <simon.kagstrom at netinsight.net>
---
ChangeLog:
    v2: Use generic __set_bit and __clear_bit for ARM

 include/asm-arm/bitops.h |   47 ++++++++++++++++++---------------------------
 1 files changed, 19 insertions(+), 28 deletions(-)

diff --git a/include/asm-arm/bitops.h b/include/asm-arm/bitops.h
index 1549da1..854e225 100644
--- a/include/asm-arm/bitops.h
+++ b/include/asm-arm/bitops.h
@@ -25,61 +25,52 @@
  */
 extern void set_bit(int nr, volatile void * addr);
 
-static inline void __set_bit(int nr, volatile void *addr)
-{
-	((unsigned char *) addr)[nr >> 3] |= (1U << (nr & 7));
-}
-#define __set_bit
-
 extern void clear_bit(int nr, volatile void * addr);
 
-static inline void __clear_bit(int nr, volatile void *addr)
-{
-	((unsigned char *) addr)[nr >> 3] &= ~(1U << (nr & 7));
-}
-#define __clear_bit
-
 extern void change_bit(int nr, volatile void * addr);
 
 static inline void __change_bit(int nr, volatile void *addr)
 {
-	((unsigned char *) addr)[nr >> 3] ^= (1U << (nr & 7));
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+
+	*p ^= mask;
 }
 
 extern int test_and_set_bit(int nr, volatile void * addr);
 
 static inline int __test_and_set_bit(int nr, volatile void *addr)
 {
-	unsigned int mask = 1 << (nr & 7);
-	unsigned int oldval;
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+	unsigned long old = *p;
 
-	oldval = ((unsigned char *) addr)[nr >> 3];
-	((unsigned char *) addr)[nr >> 3] = oldval | mask;
-	return oldval & mask;
+	*p = old | mask;
+	return (old & mask) != 0;
 }
 
 extern int test_and_clear_bit(int nr, volatile void * addr);
 
 static inline int __test_and_clear_bit(int nr, volatile void *addr)
 {
-	unsigned int mask = 1 << (nr & 7);
-	unsigned int oldval;
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+	unsigned long old = *p;
 
-	oldval = ((unsigned char *) addr)[nr >> 3];
-	((unsigned char *) addr)[nr >> 3] = oldval & ~mask;
-	return oldval & mask;
+	*p = old & ~mask;
+	return (old & mask) != 0;
 }
 
 extern int test_and_change_bit(int nr, volatile void * addr);
 
 static inline int __test_and_change_bit(int nr, volatile void *addr)
 {
-	unsigned int mask = 1 << (nr & 7);
-	unsigned int oldval;
+	unsigned long mask = BIT_MASK(nr);
+	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+	unsigned long old = *p;
 
-	oldval = ((unsigned char *) addr)[nr >> 3];
-	((unsigned char *) addr)[nr >> 3] = oldval ^ mask;
-	return oldval & mask;
+	*p = old ^ mask;
+	return (old & mask) != 0;
 }
 
 extern int find_first_zero_bit(void * addr, unsigned size);
-- 
1.6.0.4