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Diffstat (limited to 'include/asm-xtensa/atomic.h')
-rw-r--r-- | include/asm-xtensa/atomic.h | 299 |
1 files changed, 0 insertions, 299 deletions
diff --git a/include/asm-xtensa/atomic.h b/include/asm-xtensa/atomic.h deleted file mode 100644 index 67ad67b..0000000 --- a/include/asm-xtensa/atomic.h +++ /dev/null @@ -1,299 +0,0 @@ -/* - * include/asm-xtensa/atomic.h - * - * Atomic operations that C can't guarantee us. Useful for resource counting.. - * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Copyright (C) 2001 - 2005 Tensilica Inc. - */ - -#ifndef _XTENSA_ATOMIC_H -#define _XTENSA_ATOMIC_H - -#include <linux/stringify.h> -#include <linux/types.h> - -#ifdef __KERNEL__ -#include <asm/processor.h> -#include <asm/system.h> - -#define ATOMIC_INIT(i) { (i) } - -/* - * This Xtensa implementation assumes that the right mechanism - * for exclusion is for locking interrupts to level 1. - * - * Locking interrupts looks like this: - * - * rsil a15, 1 - * <code> - * wsr a15, PS - * rsync - * - * Note that a15 is used here because the register allocation - * done by the compiler is not guaranteed and a window overflow - * may not occur between the rsil and wsr instructions. By using - * a15 in the rsil, the machine is guaranteed to be in a state - * where no register reference will cause an overflow. - */ - -/** - * atomic_read - read atomic variable - * @v: pointer of type atomic_t - * - * Atomically reads the value of @v. - */ -#define atomic_read(v) ((v)->counter) - -/** - * atomic_set - set atomic variable - * @v: pointer of type atomic_t - * @i: required value - * - * Atomically sets the value of @v to @i. - */ -#define atomic_set(v,i) ((v)->counter = (i)) - -/** - * atomic_add - add integer to atomic variable - * @i: integer value to add - * @v: pointer of type atomic_t - * - * Atomically adds @i to @v. - */ -static inline void atomic_add(int i, atomic_t * v) -{ - unsigned int vval; - - __asm__ __volatile__( - "rsil a15, "__stringify(LOCKLEVEL)"\n\t" - "l32i %0, %2, 0 \n\t" - "add %0, %0, %1 \n\t" - "s32i %0, %2, 0 \n\t" - "wsr a15, "__stringify(PS)" \n\t" - "rsync \n" - : "=&a" (vval) - : "a" (i), "a" (v) - : "a15", "memory" - ); -} - -/** - * atomic_sub - subtract the atomic variable - * @i: integer value to subtract - * @v: pointer of type atomic_t - * - * Atomically subtracts @i from @v. - */ -static inline void atomic_sub(int i, atomic_t *v) -{ - unsigned int vval; - - __asm__ __volatile__( - "rsil a15, "__stringify(LOCKLEVEL)"\n\t" - "l32i %0, %2, 0 \n\t" - "sub %0, %0, %1 \n\t" - "s32i %0, %2, 0 \n\t" - "wsr a15, "__stringify(PS)" \n\t" - "rsync \n" - : "=&a" (vval) - : "a" (i), "a" (v) - : "a15", "memory" - ); -} - -/* - * We use atomic_{add|sub}_return to define other functions. - */ - -static inline int atomic_add_return(int i, atomic_t * v) -{ - unsigned int vval; - - __asm__ __volatile__( - "rsil a15,"__stringify(LOCKLEVEL)"\n\t" - "l32i %0, %2, 0 \n\t" - "add %0, %0, %1 \n\t" - "s32i %0, %2, 0 \n\t" - "wsr a15, "__stringify(PS)" \n\t" - "rsync \n" - : "=&a" (vval) - : "a" (i), "a" (v) - : "a15", "memory" - ); - - return vval; -} - -static inline int atomic_sub_return(int i, atomic_t * v) -{ - unsigned int vval; - - __asm__ __volatile__( - "rsil a15,"__stringify(LOCKLEVEL)"\n\t" - "l32i %0, %2, 0 \n\t" - "sub %0, %0, %1 \n\t" - "s32i %0, %2, 0 \n\t" - "wsr a15, "__stringify(PS)" \n\t" - "rsync \n" - : "=&a" (vval) - : "a" (i), "a" (v) - : "a15", "memory" - ); - - return vval; -} - -/** - * atomic_sub_and_test - subtract value from variable and test result - * @i: integer value to subtract - * @v: pointer of type atomic_t - * - * Atomically subtracts @i from @v and returns - * true if the result is zero, or false for all - * other cases. - */ -#define atomic_sub_and_test(i,v) (atomic_sub_return((i),(v)) == 0) - -/** - * atomic_inc - increment atomic variable - * @v: pointer of type atomic_t - * - * Atomically increments @v by 1. - */ -#define atomic_inc(v) atomic_add(1,(v)) - -/** - * atomic_inc - increment atomic variable - * @v: pointer of type atomic_t - * - * Atomically increments @v by 1. - */ -#define atomic_inc_return(v) atomic_add_return(1,(v)) - -/** - * atomic_dec - decrement atomic variable - * @v: pointer of type atomic_t - * - * Atomically decrements @v by 1. - */ -#define atomic_dec(v) atomic_sub(1,(v)) - -/** - * atomic_dec_return - decrement atomic variable - * @v: pointer of type atomic_t - * - * Atomically decrements @v by 1. - */ -#define atomic_dec_return(v) atomic_sub_return(1,(v)) - -/** - * atomic_dec_and_test - decrement and test - * @v: pointer of type atomic_t - * - * Atomically decrements @v by 1 and - * returns true if the result is 0, or false for all other - * cases. - */ -#define atomic_dec_and_test(v) (atomic_sub_return(1,(v)) == 0) - -/** - * atomic_inc_and_test - increment and test - * @v: pointer of type atomic_t - * - * Atomically increments @v by 1 - * and returns true if the result is zero, or false for all - * other cases. - */ -#define atomic_inc_and_test(v) (atomic_add_return(1,(v)) == 0) - -/** - * atomic_add_negative - add and test if negative - * @v: pointer of type atomic_t - * @i: integer value to add - * - * Atomically adds @i to @v and returns true - * if the result is negative, or false when - * result is greater than or equal to zero. - */ -#define atomic_add_negative(i,v) (atomic_add_return((i),(v)) < 0) - -#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n))) -#define atomic_xchg(v, new) (xchg(&((v)->counter), new)) - -/** - * atomic_add_unless - add unless the number is a given value - * @v: pointer of type atomic_t - * @a: the amount to add to v... - * @u: ...unless v is equal to u. - * - * Atomically adds @a to @v, so long as it was not @u. - * Returns non-zero if @v was not @u, and zero otherwise. - */ -static __inline__ int atomic_add_unless(atomic_t *v, int a, int u) -{ - int c, old; - c = atomic_read(v); - for (;;) { - if (unlikely(c == (u))) - break; - old = atomic_cmpxchg((v), c, c + (a)); - if (likely(old == c)) - break; - c = old; - } - return c != (u); -} - -#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) - -static inline void atomic_clear_mask(unsigned int mask, atomic_t *v) -{ - unsigned int all_f = -1; - unsigned int vval; - - __asm__ __volatile__( - "rsil a15,"__stringify(LOCKLEVEL)"\n\t" - "l32i %0, %2, 0 \n\t" - "xor %1, %4, %3 \n\t" - "and %0, %0, %4 \n\t" - "s32i %0, %2, 0 \n\t" - "wsr a15, "__stringify(PS)" \n\t" - "rsync \n" - : "=&a" (vval), "=a" (mask) - : "a" (v), "a" (all_f), "1" (mask) - : "a15", "memory" - ); -} - -static inline void atomic_set_mask(unsigned int mask, atomic_t *v) -{ - unsigned int vval; - - __asm__ __volatile__( - "rsil a15,"__stringify(LOCKLEVEL)"\n\t" - "l32i %0, %2, 0 \n\t" - "or %0, %0, %1 \n\t" - "s32i %0, %2, 0 \n\t" - "wsr a15, "__stringify(PS)" \n\t" - "rsync \n" - : "=&a" (vval) - : "a" (mask), "a" (v) - : "a15", "memory" - ); -} - -/* Atomic operations are already serializing */ -#define smp_mb__before_atomic_dec() barrier() -#define smp_mb__after_atomic_dec() barrier() -#define smp_mb__before_atomic_inc() barrier() -#define smp_mb__after_atomic_inc() barrier() - -#include <asm-generic/atomic.h> -#endif /* __KERNEL__ */ - -#endif /* _XTENSA_ATOMIC_H */ - |