1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * ARM64 Spinlock support 4 */ 5 #include <stdint.h> 6 7 #include "spinlock.h" 8 9 void spin_lock(struct spinlock *lock) 10 { 11 int val, res; 12 13 asm volatile( 14 "1: ldaxr %w0, [%2]\n" 15 " cbnz %w0, 1b\n" 16 " mov %w0, #1\n" 17 " stxr %w1, %w0, [%2]\n" 18 " cbnz %w1, 1b\n" 19 : "=&r" (val), "=&r" (res) 20 : "r" (&lock->v) 21 : "memory"); 22 } 23 24 void spin_unlock(struct spinlock *lock) 25 { 26 asm volatile("stlr wzr, [%0]\n" : : "r" (&lock->v) : "memory"); 27 } 28