28 lines
462 B
C
28 lines
462 B
C
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// SPDX-License-Identifier: GPL-2.0
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/*
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* ARM64 Spinlock support
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*/
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#include <stdint.h>
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#include "spinlock.h"
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void spin_lock(struct spinlock *lock)
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{
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int val, res;
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asm volatile(
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"1: ldaxr %w0, [%2]\n"
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" cbnz %w0, 1b\n"
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" mov %w0, #1\n"
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" stxr %w1, %w0, [%2]\n"
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" cbnz %w1, 1b\n"
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: "=&r" (val), "=&r" (res)
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: "r" (&lock->v)
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: "memory");
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}
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void spin_unlock(struct spinlock *lock)
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{
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asm volatile("stlr wzr, [%0]\n" : : "r" (&lock->v) : "memory");
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}
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