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diff --git a/arch/xtensa/include/asm/atomic.h b/arch/xtensa/include/asm/atomic.h
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+/*
+ * 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 - 2008 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/cmpxchg.h>
+#include <asm/barrier.h>
+
+#define ATOMIC_INIT(i) { (i) }
+
+/*
+ * This Xtensa implementation assumes that the right mechanism
+ * for exclusion is for locking interrupts to level EXCM_LEVEL.
+ *
+ * Locking interrupts looks like this:
+ *
+ * rsil a15, LOCKLEVEL
+ * <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) ACCESS_ONCE((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))
+
+#if XCHAL_HAVE_S32C1I
+#define ATOMIC_OP(op) \
+static inline void atomic_##op(int i, atomic_t * v) \
+{ \
+ unsigned long tmp; \
+ int result; \
+ \
+ __asm__ __volatile__( \
+ "1: l32i %1, %3, 0\n" \
+ " wsr %1, scompare1\n" \
+ " " #op " %0, %1, %2\n" \
+ " s32c1i %0, %3, 0\n" \
+ " bne %0, %1, 1b\n" \
+ : "=&a" (result), "=&a" (tmp) \
+ : "a" (i), "a" (v) \
+ : "memory" \
+ ); \
+} \
+
+#define ATOMIC_OP_RETURN(op) \
+static inline int atomic_##op##_return(int i, atomic_t * v) \
+{ \
+ unsigned long tmp; \
+ int result; \
+ \
+ __asm__ __volatile__( \
+ "1: l32i %1, %3, 0\n" \
+ " wsr %1, scompare1\n" \
+ " " #op " %0, %1, %2\n" \
+ " s32c1i %0, %3, 0\n" \
+ " bne %0, %1, 1b\n" \
+ " " #op " %0, %0, %2\n" \
+ : "=&a" (result), "=&a" (tmp) \
+ : "a" (i), "a" (v) \
+ : "memory" \
+ ); \
+ \
+ return result; \
+}
+
+#else /* XCHAL_HAVE_S32C1I */
+
+#define ATOMIC_OP(op) \
+static inline void atomic_##op(int i, atomic_t * v) \
+{ \
+ unsigned int vval; \
+ \
+ __asm__ __volatile__( \
+ " rsil a15, "__stringify(LOCKLEVEL)"\n"\
+ " l32i %0, %2, 0\n" \
+ " " #op " %0, %0, %1\n" \
+ " s32i %0, %2, 0\n" \
+ " wsr a15, ps\n" \
+ " rsync\n" \
+ : "=&a" (vval) \
+ : "a" (i), "a" (v) \
+ : "a15", "memory" \
+ ); \
+} \
+
+#define ATOMIC_OP_RETURN(op) \
+static inline int atomic_##op##_return(int i, atomic_t * v) \
+{ \
+ unsigned int vval; \
+ \
+ __asm__ __volatile__( \
+ " rsil a15,"__stringify(LOCKLEVEL)"\n" \
+ " l32i %0, %2, 0\n" \
+ " " #op " %0, %0, %1\n" \
+ " s32i %0, %2, 0\n" \
+ " wsr a15, ps\n" \
+ " rsync\n" \
+ : "=&a" (vval) \
+ : "a" (i), "a" (v) \
+ : "a15", "memory" \
+ ); \
+ \
+ return vval; \
+}
+
+#endif /* XCHAL_HAVE_S32C1I */
+
+#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
+
+ATOMIC_OPS(add)
+ATOMIC_OPS(sub)
+
+#undef ATOMIC_OPS
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+/**
+ * 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 the old value of @v.
+ */
+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;
+}
+
+
+static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
+{
+#if XCHAL_HAVE_S32C1I
+ unsigned long tmp;
+ int result;
+
+ __asm__ __volatile__(
+ "1: l32i %1, %3, 0\n"
+ " wsr %1, scompare1\n"
+ " and %0, %1, %2\n"
+ " s32c1i %0, %3, 0\n"
+ " bne %0, %1, 1b\n"
+ : "=&a" (result), "=&a" (tmp)
+ : "a" (~mask), "a" (v)
+ : "memory"
+ );
+#else
+ unsigned int all_f = -1;
+ unsigned int vval;
+
+ __asm__ __volatile__(
+ " rsil a15,"__stringify(LOCKLEVEL)"\n"
+ " l32i %0, %2, 0\n"
+ " xor %1, %4, %3\n"
+ " and %0, %0, %4\n"
+ " s32i %0, %2, 0\n"
+ " wsr a15, ps\n"
+ " rsync\n"
+ : "=&a" (vval), "=a" (mask)
+ : "a" (v), "a" (all_f), "1" (mask)
+ : "a15", "memory"
+ );
+#endif
+}
+
+static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
+{
+#if XCHAL_HAVE_S32C1I
+ unsigned long tmp;
+ int result;
+
+ __asm__ __volatile__(
+ "1: l32i %1, %3, 0\n"
+ " wsr %1, scompare1\n"
+ " or %0, %1, %2\n"
+ " s32c1i %0, %3, 0\n"
+ " bne %0, %1, 1b\n"
+ : "=&a" (result), "=&a" (tmp)
+ : "a" (mask), "a" (v)
+ : "memory"
+ );
+#else
+ unsigned int vval;
+
+ __asm__ __volatile__(
+ " rsil a15,"__stringify(LOCKLEVEL)"\n"
+ " l32i %0, %2, 0\n"
+ " or %0, %0, %1\n"
+ " s32i %0, %2, 0\n"
+ " wsr a15, ps\n"
+ " rsync\n"
+ : "=&a" (vval)
+ : "a" (mask), "a" (v)
+ : "a15", "memory"
+ );
+#endif
+}
+
+#endif /* __KERNEL__ */
+
+#endif /* _XTENSA_ATOMIC_H */
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