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/*
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/*
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 * Copyright (c) 2005 Ondrej Palkovsky
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 * Copyright (c) 2007 Michal Kebrt
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 * All rights reserved.
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 * All rights reserved.
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 *
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * are met:
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 */
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 */
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/** @addtogroup arm32  
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/** @addtogroup arm32  
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 * @{
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 * @{
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 */
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 */
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/** @file
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/** @file
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 *  @brief Atomic operations.
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 */
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 */
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#ifndef KERN_arm32_ATOMIC_H_
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#ifndef KERN_arm32_ATOMIC_H_
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#define KERN_arm32_ATOMIC_H_
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#define KERN_arm32_ATOMIC_H_
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/** Atomic addition.
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 *
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 * @param val Where to add.
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#define atomic_inc(x)   ((void) atomic_add(x, 1))
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 * @param i   Value to be added.
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 *
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 * @return Value after addition.
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 */
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#define atomic_dec(x)   ((void) atomic_add(x, -1))
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static inline long atomic_add(atomic_t *val, int i)
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{
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    int ret;
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    volatile long *mem = &(val->count);
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    asm volatile (
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    "1:\n"
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        "ldr r2, [%1]       \n"
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        "add r3, r2, %2     \n"
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        "str r3, %0         \n"
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        "swp r3, r3, [%1]   \n"
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        "cmp r3, r2         \n"
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#define atomic_postinc(x) (atomic_add(x, 1) - 1)
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        "bne 1b             \n"
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        : "=m" (ret)
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#define atomic_postdec(x) (atomic_add(x, -1) + 1)
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        : "r" (mem), "r" (i)
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        : "r3", "r2"
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    );
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#define atomic_preinc(x) atomic_add(x, 1)
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    return ret;
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#define atomic_predec(x) atomic_add(x, -1)
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}
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/* Atomic addition of immediate value.
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/** Atomic increment.
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 *
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 *
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 * @param val Memory location to which will be the immediate value added.
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 * @param val Variable to be incremented.
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 */
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 * @param i Signed immediate that will be added to *val.
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static inline void atomic_inc(atomic_t *val)
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{
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    atomic_add(val, 1);
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}
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/** Atomic decrement.
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 *
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 *
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 * @return Value after addition.
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 * @param val Variable to be decremented.
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 */
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 */
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static inline void atomic_dec(atomic_t *val) {
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    atomic_add(val, -1);
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}
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/** Atomic pre-increment.
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 *
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 * @param val Variable to be incremented.
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 * @return    Value after incrementation.
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 */
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static inline long atomic_preinc(atomic_t *val)
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{
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    return atomic_add(val, 1);
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}
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/** Atomic pre-decrement.
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 *
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 * @param val Variable to be decremented.
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 * @return    Value after decrementation.
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 */
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static inline long atomic_add(atomic_t *val, int i)
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static inline long atomic_predec(atomic_t *val)
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{
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    return atomic_add(val, -1);
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}
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/** Atomic post-increment.
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 *
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 * @param val Variable to be incremented.
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 * @return    Value before incrementation.
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 */
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static inline long atomic_postinc(atomic_t *val)
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{
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    return atomic_add(val, 1) - 1;
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}
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/** Atomic post-decrement.
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 *
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 * @param val Variable to be decremented.
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 * @return    Value before decrementation.
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 */
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static inline long atomic_postdec(atomic_t *val)
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{
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{
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    /* TODO */
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    return (val->count += i);
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    return atomic_add(val, -1) + 1;
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}
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}
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#endif
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#endif
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/** @}
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/** @}