projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| ae473946 DH |
1 | /* |
| 2 | * Atomic operations that C can't guarantee us. Useful for | |
| 3 | * resource counting etc. | |
| 4 | * | |
| 5 | * But use these as seldom as possible since they are slower than | |
| 6 | * regular operations. | |
| 7 | * | |
| 8 | * Copyright (C) 2004-2006 Atmel Corporation | |
| 9 | * | |
| 10 | * This program is free software; you can redistribute it and/or modify | |
| 11 | * it under the terms of the GNU General Public License version 2 as | |
| 12 | * published by the Free Software Foundation. | |
| 13 | */ | |
| 14 | #ifndef __ASM_AVR32_CMPXCHG_H | |
| 15 | #define __ASM_AVR32_CMPXCHG_H | |
| 16 | ||
| 17 | #define xchg(ptr,x) \ | |
| 18 | ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) | |
| 19 | ||
| 20 | extern void __xchg_called_with_bad_pointer(void); | |
| 21 | ||
| 22 | static inline unsigned long xchg_u32(u32 val, volatile u32 *m) | |
| 23 | { | |
| 24 | u32 ret; | |
| 25 | ||
| 26 | asm volatile("xchg %[ret], %[m], %[val]" | |
| 27 | : [ret] "=&r"(ret), "=m"(*m) | |
| 28 | : "m"(*m), [m] "r"(m), [val] "r"(val) | |
| 29 | : "memory"); | |
| 30 | return ret; | |
| 31 | } | |
| 32 | ||
| 33 | static inline unsigned long __xchg(unsigned long x, | |
| 34 | volatile void *ptr, | |
| 35 | int size) | |
| 36 | { | |
| 37 | switch(size) { | |
| 38 | case 4: | |
| 39 | return xchg_u32(x, ptr); | |
| 40 | default: | |
| 41 | __xchg_called_with_bad_pointer(); | |
| 42 | return x; | |
| 43 | } | |
| 44 | } | |
| 45 | ||
| 46 | static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old, | |
| 47 | unsigned long new) | |
| 48 | { | |
| 49 | __u32 ret; | |
| 50 | ||
| 51 | asm volatile( | |
| 52 | "1: ssrf 5\n" | |
| 53 | " ld.w %[ret], %[m]\n" | |
| 54 | " cp.w %[ret], %[old]\n" | |
| 55 | " brne 2f\n" | |
| 56 | " stcond %[m], %[new]\n" | |
| 57 | " brne 1b\n" | |
| 58 | "2:\n" | |
| 59 | : [ret] "=&r"(ret), [m] "=m"(*m) | |
| 392c5174 | 60 | : "m"(m), [old] "Ks21r"(old), [new] "r"(new) |
| ae473946 DH |
61 | : "memory", "cc"); |
| 62 | return ret; | |
| 63 | } | |
| 64 | ||
| 65 | extern unsigned long __cmpxchg_u64_unsupported_on_32bit_kernels( | |
| 66 | volatile int * m, unsigned long old, unsigned long new); | |
| 67 | #define __cmpxchg_u64 __cmpxchg_u64_unsupported_on_32bit_kernels | |
| 68 | ||
| 69 | /* This function doesn't exist, so you'll get a linker error | |
| 70 | if something tries to do an invalid cmpxchg(). */ | |
| 71 | extern void __cmpxchg_called_with_bad_pointer(void); | |
| 72 | ||
| ae473946 DH |
73 | static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, |
| 74 | unsigned long new, int size) | |
| 75 | { | |
| 76 | switch (size) { | |
| 77 | case 4: | |
| 78 | return __cmpxchg_u32(ptr, old, new); | |
| 79 | case 8: | |
| 80 | return __cmpxchg_u64(ptr, old, new); | |
| 81 | } | |
| 82 | ||
| 83 | __cmpxchg_called_with_bad_pointer(); | |
| 84 | return old; | |
| 85 | } | |
| 86 | ||
| 87 | #define cmpxchg(ptr, old, new) \ | |
| 88 | ((typeof(*(ptr)))__cmpxchg((ptr), (unsigned long)(old), \ | |
| 89 | (unsigned long)(new), \ | |
| 90 | sizeof(*(ptr)))) | |
| 91 | ||
| 92 | #include <asm-generic/cmpxchg-local.h> | |
| 93 | ||
| 94 | static inline unsigned long __cmpxchg_local(volatile void *ptr, | |
| 95 | unsigned long old, | |
| 96 | unsigned long new, int size) | |
| 97 | { | |
| 98 | switch (size) { | |
| 99 | case 4: | |
| 100 | return __cmpxchg_u32(ptr, old, new); | |
| 101 | default: | |
| 102 | return __cmpxchg_local_generic(ptr, old, new, size); | |
| 103 | } | |
| 104 | ||
| 105 | return old; | |
| 106 | } | |
| 107 | ||
| 108 | #define cmpxchg_local(ptr, old, new) \ | |
| 109 | ((typeof(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(old), \ | |
| 110 | (unsigned long)(new), \ | |
| 111 | sizeof(*(ptr)))) | |
| 112 | ||
| 113 | #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) | |
| 114 | ||
| 115 | #endif /* __ASM_AVR32_CMPXCHG_H */ |