Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef __ASM_SPINLOCK_H |
| 2 | #define __ASM_SPINLOCK_H |
| 3 | |
| 4 | #include <asm/system.h> |
| 5 | |
| 6 | /* |
| 7 | * Simple spin lock operations. |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 8 | * |
| 9 | * (the type definitions are in asm/raw_spinlock_types.h) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | */ |
| 11 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 12 | #define __raw_spin_is_locked(x) ((x)->lock != 0) |
| 13 | #define __raw_spin_unlock_wait(lock) \ |
| 14 | do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0) |
| 15 | #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 17 | static inline void __raw_spin_lock(raw_spinlock_t *lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | { |
| 19 | unsigned long tmp; |
| 20 | |
| 21 | __asm__ __volatile__( |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 22 | "b 1f # __raw_spin_lock\n\ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | 2: lwzx %0,0,%1\n\ |
| 24 | cmpwi 0,%0,0\n\ |
| 25 | bne+ 2b\n\ |
| 26 | 1: lwarx %0,0,%1\n\ |
| 27 | cmpwi 0,%0,0\n\ |
| 28 | bne- 2b\n" |
| 29 | PPC405_ERR77(0,%1) |
| 30 | " stwcx. %2,0,%1\n\ |
| 31 | bne- 2b\n\ |
| 32 | isync" |
| 33 | : "=&r"(tmp) |
| 34 | : "r"(&lock->lock), "r"(1) |
| 35 | : "cr0", "memory"); |
| 36 | } |
| 37 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 38 | static inline void __raw_spin_unlock(raw_spinlock_t *lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | { |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 40 | __asm__ __volatile__("eieio # __raw_spin_unlock": : :"memory"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | lock->lock = 0; |
| 42 | } |
| 43 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 44 | #define __raw_spin_trylock(l) (!test_and_set_bit(0,&(l)->lock)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | |
| 46 | /* |
| 47 | * Read-write spinlocks, allowing multiple readers |
| 48 | * but only one writer. |
| 49 | * |
| 50 | * NOTE! it is quite common to have readers in interrupts |
| 51 | * but no interrupt writers. For those circumstances we |
| 52 | * can "mix" irq-safe locks - any writer needs to get a |
| 53 | * irq-safe write-lock, but readers can get non-irqsafe |
| 54 | * read-locks. |
| 55 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 57 | #define __raw_read_can_lock(rw) ((rw)->lock >= 0) |
| 58 | #define __raw_write_can_lock(rw) (!(rw)->lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 60 | static __inline__ int __raw_read_trylock(raw_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | { |
| 62 | signed int tmp; |
| 63 | |
| 64 | __asm__ __volatile__( |
| 65 | "2: lwarx %0,0,%1 # read_trylock\n\ |
| 66 | addic. %0,%0,1\n\ |
| 67 | ble- 1f\n" |
| 68 | PPC405_ERR77(0,%1) |
| 69 | " stwcx. %0,0,%1\n\ |
| 70 | bne- 2b\n\ |
| 71 | isync\n\ |
| 72 | 1:" |
| 73 | : "=&r"(tmp) |
| 74 | : "r"(&rw->lock) |
| 75 | : "cr0", "memory"); |
| 76 | |
| 77 | return tmp > 0; |
| 78 | } |
| 79 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 80 | static __inline__ void __raw_read_lock(raw_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | { |
| 82 | signed int tmp; |
| 83 | |
| 84 | __asm__ __volatile__( |
| 85 | "b 2f # read_lock\n\ |
| 86 | 1: lwzx %0,0,%1\n\ |
| 87 | cmpwi 0,%0,0\n\ |
| 88 | blt+ 1b\n\ |
| 89 | 2: lwarx %0,0,%1\n\ |
| 90 | addic. %0,%0,1\n\ |
| 91 | ble- 1b\n" |
| 92 | PPC405_ERR77(0,%1) |
| 93 | " stwcx. %0,0,%1\n\ |
| 94 | bne- 2b\n\ |
| 95 | isync" |
| 96 | : "=&r"(tmp) |
| 97 | : "r"(&rw->lock) |
| 98 | : "cr0", "memory"); |
| 99 | } |
| 100 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 101 | static __inline__ void __raw_read_unlock(raw_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | { |
| 103 | signed int tmp; |
| 104 | |
| 105 | __asm__ __volatile__( |
| 106 | "eieio # read_unlock\n\ |
| 107 | 1: lwarx %0,0,%1\n\ |
| 108 | addic %0,%0,-1\n" |
| 109 | PPC405_ERR77(0,%1) |
| 110 | " stwcx. %0,0,%1\n\ |
| 111 | bne- 1b" |
| 112 | : "=&r"(tmp) |
| 113 | : "r"(&rw->lock) |
| 114 | : "cr0", "memory"); |
| 115 | } |
| 116 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 117 | static __inline__ int __raw_write_trylock(raw_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | { |
| 119 | signed int tmp; |
| 120 | |
| 121 | __asm__ __volatile__( |
| 122 | "2: lwarx %0,0,%1 # write_trylock\n\ |
| 123 | cmpwi 0,%0,0\n\ |
| 124 | bne- 1f\n" |
| 125 | PPC405_ERR77(0,%1) |
| 126 | " stwcx. %2,0,%1\n\ |
| 127 | bne- 2b\n\ |
| 128 | isync\n\ |
| 129 | 1:" |
| 130 | : "=&r"(tmp) |
| 131 | : "r"(&rw->lock), "r"(-1) |
| 132 | : "cr0", "memory"); |
| 133 | |
| 134 | return tmp == 0; |
| 135 | } |
| 136 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 137 | static __inline__ void __raw_write_lock(raw_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | { |
| 139 | signed int tmp; |
| 140 | |
| 141 | __asm__ __volatile__( |
| 142 | "b 2f # write_lock\n\ |
| 143 | 1: lwzx %0,0,%1\n\ |
| 144 | cmpwi 0,%0,0\n\ |
| 145 | bne+ 1b\n\ |
| 146 | 2: lwarx %0,0,%1\n\ |
| 147 | cmpwi 0,%0,0\n\ |
| 148 | bne- 1b\n" |
| 149 | PPC405_ERR77(0,%1) |
| 150 | " stwcx. %2,0,%1\n\ |
| 151 | bne- 2b\n\ |
| 152 | isync" |
| 153 | : "=&r"(tmp) |
| 154 | : "r"(&rw->lock), "r"(-1) |
| 155 | : "cr0", "memory"); |
| 156 | } |
| 157 | |
Ingo Molnar | fb1c8f9 | 2005-09-10 00:25:56 -0700 | [diff] [blame] | 158 | static __inline__ void __raw_write_unlock(raw_rwlock_t *rw) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | { |
| 160 | __asm__ __volatile__("eieio # write_unlock": : :"memory"); |
| 161 | rw->lock = 0; |
| 162 | } |
| 163 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | #endif /* __ASM_SPINLOCK_H */ |