David Howells | 3bed8d6 | 2012-03-12 23:36:56 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2004-2011 Analog Devices Inc. |
| 3 | * |
| 4 | * Licensed under the GPL-2 or later. |
| 5 | */ |
| 6 | |
| 7 | #ifndef __ARCH_BLACKFIN_CMPXCHG__ |
| 8 | #define __ARCH_BLACKFIN_CMPXCHG__ |
| 9 | |
| 10 | #ifdef CONFIG_SMP |
| 11 | |
| 12 | #include <linux/linkage.h> |
| 13 | |
| 14 | asmlinkage unsigned long __raw_xchg_1_asm(volatile void *ptr, unsigned long value); |
| 15 | asmlinkage unsigned long __raw_xchg_2_asm(volatile void *ptr, unsigned long value); |
| 16 | asmlinkage unsigned long __raw_xchg_4_asm(volatile void *ptr, unsigned long value); |
| 17 | asmlinkage unsigned long __raw_cmpxchg_1_asm(volatile void *ptr, |
| 18 | unsigned long new, unsigned long old); |
| 19 | asmlinkage unsigned long __raw_cmpxchg_2_asm(volatile void *ptr, |
| 20 | unsigned long new, unsigned long old); |
| 21 | asmlinkage unsigned long __raw_cmpxchg_4_asm(volatile void *ptr, |
| 22 | unsigned long new, unsigned long old); |
| 23 | |
| 24 | static inline unsigned long __xchg(unsigned long x, volatile void *ptr, |
| 25 | int size) |
| 26 | { |
| 27 | unsigned long tmp; |
| 28 | |
| 29 | switch (size) { |
| 30 | case 1: |
| 31 | tmp = __raw_xchg_1_asm(ptr, x); |
| 32 | break; |
| 33 | case 2: |
| 34 | tmp = __raw_xchg_2_asm(ptr, x); |
| 35 | break; |
| 36 | case 4: |
| 37 | tmp = __raw_xchg_4_asm(ptr, x); |
| 38 | break; |
| 39 | } |
| 40 | |
| 41 | return tmp; |
| 42 | } |
| 43 | |
| 44 | /* |
| 45 | * Atomic compare and exchange. Compare OLD with MEM, if identical, |
| 46 | * store NEW in MEM. Return the initial value in MEM. Success is |
| 47 | * indicated by comparing RETURN with OLD. |
| 48 | */ |
| 49 | static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, |
| 50 | unsigned long new, int size) |
| 51 | { |
| 52 | unsigned long tmp; |
| 53 | |
| 54 | switch (size) { |
| 55 | case 1: |
| 56 | tmp = __raw_cmpxchg_1_asm(ptr, new, old); |
| 57 | break; |
| 58 | case 2: |
| 59 | tmp = __raw_cmpxchg_2_asm(ptr, new, old); |
| 60 | break; |
| 61 | case 4: |
| 62 | tmp = __raw_cmpxchg_4_asm(ptr, new, old); |
| 63 | break; |
| 64 | } |
| 65 | |
| 66 | return tmp; |
| 67 | } |
| 68 | #define cmpxchg(ptr, o, n) \ |
| 69 | ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \ |
| 70 | (unsigned long)(n), sizeof(*(ptr)))) |
| 71 | |
| 72 | #else /* !CONFIG_SMP */ |
| 73 | |
| 74 | #include <mach/blackfin.h> |
| 75 | #include <asm/irqflags.h> |
| 76 | |
| 77 | struct __xchg_dummy { |
| 78 | unsigned long a[100]; |
| 79 | }; |
| 80 | #define __xg(x) ((volatile struct __xchg_dummy *)(x)) |
| 81 | |
| 82 | static inline unsigned long __xchg(unsigned long x, volatile void *ptr, |
| 83 | int size) |
| 84 | { |
| 85 | unsigned long tmp = 0; |
| 86 | unsigned long flags; |
| 87 | |
| 88 | flags = hard_local_irq_save(); |
| 89 | |
| 90 | switch (size) { |
| 91 | case 1: |
| 92 | __asm__ __volatile__ |
| 93 | ("%0 = b%2 (z);\n\t" |
| 94 | "b%2 = %1;\n\t" |
| 95 | : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); |
| 96 | break; |
| 97 | case 2: |
| 98 | __asm__ __volatile__ |
| 99 | ("%0 = w%2 (z);\n\t" |
| 100 | "w%2 = %1;\n\t" |
| 101 | : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); |
| 102 | break; |
| 103 | case 4: |
| 104 | __asm__ __volatile__ |
| 105 | ("%0 = %2;\n\t" |
| 106 | "%2 = %1;\n\t" |
| 107 | : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); |
| 108 | break; |
| 109 | } |
| 110 | hard_local_irq_restore(flags); |
| 111 | return tmp; |
| 112 | } |
| 113 | |
| 114 | #include <asm-generic/cmpxchg-local.h> |
| 115 | |
| 116 | /* |
| 117 | * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make |
| 118 | * them available. |
| 119 | */ |
| 120 | #define cmpxchg_local(ptr, o, n) \ |
| 121 | ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ |
| 122 | (unsigned long)(n), sizeof(*(ptr)))) |
| 123 | #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) |
| 124 | |
Paul Gortmaker | 1512cdc | 2012-04-01 16:38:41 -0400 | [diff] [blame] | 125 | #define cmpxchg(ptr, o, n) cmpxchg_local((ptr), (o), (n)) |
| 126 | #define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n)) |
David Howells | 3bed8d6 | 2012-03-12 23:36:56 +0000 | [diff] [blame] | 127 | |
| 128 | #endif /* !CONFIG_SMP */ |
| 129 | |
| 130 | #define xchg(ptr, x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr)))) |
| 131 | #define tas(ptr) ((void)xchg((ptr), 1)) |
| 132 | |
| 133 | #endif /* __ARCH_BLACKFIN_CMPXCHG__ */ |