/* asm/bitops.h for Linux/CRIS
*
* TODO: asm versions if speed is needed
*
* All bit operations return 0 if the bit was cleared before the
* operation and != 0 if it was not.
*
* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
*/
#ifndef _CRIS_BITOPS_H
#define _CRIS_BITOPS_H
/* Currently this is unsuitable for consumption outside the kernel. */
#ifdef __KERNEL__
#include <asm/arch/bitops.h>
#include <asm/system.h>
#include <asm/atomic.h>
#include <linux/compiler.h>
/*
* Some hacks to defeat gcc over-optimizations..
*/
struct __dummy { unsigned long a[100]; };
#define ADDR (*(struct __dummy *) addr)
#define CONST_ADDR (*(const struct __dummy *) addr)
/*
* set_bit - Atomically set a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
*
* This function is atomic and may not be reordered. See __set_bit()
* if you do not require the atomic guarantees.
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
#define set_bit(nr, addr) (void)test_and_set_bit(nr, addr)
/*
* clear_bit - Clears a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* clear_bit() is atomic and may not be reordered. However, it does
* not contain a memory barrier, so if it is used for locking purposes,
* you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
* in order to ensure changes are visible on other processors.
*/
#define clear_bit(nr, addr) (void)test_and_clear_bit(nr, addr)
/*
* change_bit - Toggle a bit in memory
* @nr: Bit to change
* @addr: Address to start counting from
*
* change_bit() is atomic and may not be reordered.
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
#define change_bit(nr, addr) (void)test_and_change_bit(nr, addr)
/**
* test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_set_bit(int nr, volatile unsigned long *addr)
{
unsigned int mask, retval;
unsigned long flags;
unsigned int *adr = (unsigned int *)addr;
adr += nr >> 5;
mask = 1 << (nr & 0x1f);
cris_atomic_save(addr, flags);
retval = (mask & *adr) != 0;
*adr |= mask;
cris_atomic_restore(addr, flags);
return retval;
}
/*
* clear_bit() doesn't provide any barrier for the compiler.
*/
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
/**
* test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to clear
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_clear_bit(int nr, volatile unsigned long *addr)
{
unsigned int mask, retval;
unsigned long flags;
unsigned int *adr = (unsigned int *)addr;
adr += nr >> 5;
mask = 1 << (nr & 0x1f);
cris_atomic_save(addr, flags);
retval = (mask & *adr) != 0;
*adr &= ~mask;
cris_atomic_restore(addr, flags);
return retval;
}
/**
* test_and_change_bit - Change a bit and return its old value
* @nr: Bit to change
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_change_bit(int nr, volatile unsigned long *addr)
{
unsigned int mask, retval;
unsigned long flags;
unsigned int *adr = (unsigned int *)addr;
adr += nr >> 5;
mask = 1 << (nr & 0x1f);
cris_atomic_save(addr, flags);
retval = (mask & *adr) != 0;
*adr ^= mask;
cris_atomic_restore(addr, flags);
return retval;
}
#include <asm-generic/bitops/non-atomic.h>
/*
* Since we define it "external", it collides with the built-in
* definition, which doesn't have the same semantics. We don't want to
* use -fno-builtin, so just hide the name ffs.
*/
#define ffs kernel_ffs
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/find.h>
#include <asm-generic/bitops/ext2-non-atomic.h>
#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a)
#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
#include <asm-generic/bitops/minix.h>
#include <asm-generic/bitops/sched.h>
#endif /* __KERNEL__ */
#endif /* _CRIS_BITOPS_H */
