[U-Boot] [PATCH v3 2/4]: arm: Make arm bitops endianness-independent

Simon Kagstrom
2009-08-21T08:28:58Z

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.

v2: Use generic __set_bit and __clear_bit for ARM

Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
---
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