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-rw-r--r--include/asm-arm/spinlock.h224
1 files changed, 0 insertions, 224 deletions
diff --git a/include/asm-arm/spinlock.h b/include/asm-arm/spinlock.h
deleted file mode 100644
index 2b41ebb..0000000
--- a/include/asm-arm/spinlock.h
+++ /dev/null
@@ -1,224 +0,0 @@
-#ifndef __ASM_SPINLOCK_H
-#define __ASM_SPINLOCK_H
-
-#if __LINUX_ARM_ARCH__ < 6
-#error SMP not supported on pre-ARMv6 CPUs
-#endif
-
-/*
- * ARMv6 Spin-locking.
- *
- * We exclusively read the old value. If it is zero, we may have
- * won the lock, so we try exclusively storing it. A memory barrier
- * is required after we get a lock, and before we release it, because
- * V6 CPUs are assumed to have weakly ordered memory.
- *
- * Unlocked value: 0
- * Locked value: 1
- */
-
-#define __raw_spin_is_locked(x) ((x)->lock != 0)
-#define __raw_spin_unlock_wait(lock) \
- do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0)
-
-#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
-
-static inline void __raw_spin_lock(raw_spinlock_t *lock)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
-"1: ldrex %0, [%1]\n"
-" teq %0, #0\n"
-#ifdef CONFIG_CPU_32v6K
-" wfene\n"
-#endif
-" strexeq %0, %2, [%1]\n"
-" teqeq %0, #0\n"
-" bne 1b"
- : "=&r" (tmp)
- : "r" (&lock->lock), "r" (1)
- : "cc");
-
- smp_mb();
-}
-
-static inline int __raw_spin_trylock(raw_spinlock_t *lock)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
-" ldrex %0, [%1]\n"
-" teq %0, #0\n"
-" strexeq %0, %2, [%1]"
- : "=&r" (tmp)
- : "r" (&lock->lock), "r" (1)
- : "cc");
-
- if (tmp == 0) {
- smp_mb();
- return 1;
- } else {
- return 0;
- }
-}
-
-static inline void __raw_spin_unlock(raw_spinlock_t *lock)
-{
- smp_mb();
-
- __asm__ __volatile__(
-" str %1, [%0]\n"
-#ifdef CONFIG_CPU_32v6K
-" mcr p15, 0, %1, c7, c10, 4\n" /* DSB */
-" sev"
-#endif
- :
- : "r" (&lock->lock), "r" (0)
- : "cc");
-}
-
-/*
- * RWLOCKS
- *
- *
- * Write locks are easy - we just set bit 31. When unlocking, we can
- * just write zero since the lock is exclusively held.
- */
-
-static inline void __raw_write_lock(raw_rwlock_t *rw)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
-"1: ldrex %0, [%1]\n"
-" teq %0, #0\n"
-#ifdef CONFIG_CPU_32v6K
-" wfene\n"
-#endif
-" strexeq %0, %2, [%1]\n"
-" teq %0, #0\n"
-" bne 1b"
- : "=&r" (tmp)
- : "r" (&rw->lock), "r" (0x80000000)
- : "cc");
-
- smp_mb();
-}
-
-static inline int __raw_write_trylock(raw_rwlock_t *rw)
-{
- unsigned long tmp;
-
- __asm__ __volatile__(
-"1: ldrex %0, [%1]\n"
-" teq %0, #0\n"
-" strexeq %0, %2, [%1]"
- : "=&r" (tmp)
- : "r" (&rw->lock), "r" (0x80000000)
- : "cc");
-
- if (tmp == 0) {
- smp_mb();
- return 1;
- } else {
- return 0;
- }
-}
-
-static inline void __raw_write_unlock(raw_rwlock_t *rw)
-{
- smp_mb();
-
- __asm__ __volatile__(
- "str %1, [%0]\n"
-#ifdef CONFIG_CPU_32v6K
-" mcr p15, 0, %1, c7, c10, 4\n" /* DSB */
-" sev\n"
-#endif
- :
- : "r" (&rw->lock), "r" (0)
- : "cc");
-}
-
-/* write_can_lock - would write_trylock() succeed? */
-#define __raw_write_can_lock(x) ((x)->lock == 0)
-
-/*
- * Read locks are a bit more hairy:
- * - Exclusively load the lock value.
- * - Increment it.
- * - Store new lock value if positive, and we still own this location.
- * If the value is negative, we've already failed.
- * - If we failed to store the value, we want a negative result.
- * - If we failed, try again.
- * Unlocking is similarly hairy. We may have multiple read locks
- * currently active. However, we know we won't have any write
- * locks.
- */
-static inline void __raw_read_lock(raw_rwlock_t *rw)
-{
- unsigned long tmp, tmp2;
-
- __asm__ __volatile__(
-"1: ldrex %0, [%2]\n"
-" adds %0, %0, #1\n"
-" strexpl %1, %0, [%2]\n"
-#ifdef CONFIG_CPU_32v6K
-" wfemi\n"
-#endif
-" rsbpls %0, %1, #0\n"
-" bmi 1b"
- : "=&r" (tmp), "=&r" (tmp2)
- : "r" (&rw->lock)
- : "cc");
-
- smp_mb();
-}
-
-static inline void __raw_read_unlock(raw_rwlock_t *rw)
-{
- unsigned long tmp, tmp2;
-
- smp_mb();
-
- __asm__ __volatile__(
-"1: ldrex %0, [%2]\n"
-" sub %0, %0, #1\n"
-" strex %1, %0, [%2]\n"
-" teq %1, #0\n"
-" bne 1b"
-#ifdef CONFIG_CPU_32v6K
-"\n cmp %0, #0\n"
-" mcreq p15, 0, %0, c7, c10, 4\n"
-" seveq"
-#endif
- : "=&r" (tmp), "=&r" (tmp2)
- : "r" (&rw->lock)
- : "cc");
-}
-
-static inline int __raw_read_trylock(raw_rwlock_t *rw)
-{
- unsigned long tmp, tmp2 = 1;
-
- __asm__ __volatile__(
-"1: ldrex %0, [%2]\n"
-" adds %0, %0, #1\n"
-" strexpl %1, %0, [%2]\n"
- : "=&r" (tmp), "+r" (tmp2)
- : "r" (&rw->lock)
- : "cc");
-
- smp_mb();
- return tmp2 == 0;
-}
-
-/* read_can_lock - would read_trylock() succeed? */
-#define __raw_read_can_lock(x) ((x)->lock < 0x80000000)
-
-#define _raw_spin_relax(lock) cpu_relax()
-#define _raw_read_relax(lock) cpu_relax()
-#define _raw_write_relax(lock) cpu_relax()
-
-#endif /* __ASM_SPINLOCK_H */