diff options
Diffstat (limited to 'arch/arm/include/asm/delay.h')
-rw-r--r-- | arch/arm/include/asm/delay.h | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/arch/arm/include/asm/delay.h b/arch/arm/include/asm/delay.h index b2deda181549..dc6145120de3 100644 --- a/arch/arm/include/asm/delay.h +++ b/arch/arm/include/asm/delay.h | |||
@@ -6,9 +6,22 @@ | |||
6 | #ifndef __ASM_ARM_DELAY_H | 6 | #ifndef __ASM_ARM_DELAY_H |
7 | #define __ASM_ARM_DELAY_H | 7 | #define __ASM_ARM_DELAY_H |
8 | 8 | ||
9 | #include <asm/memory.h> | ||
9 | #include <asm/param.h> /* HZ */ | 10 | #include <asm/param.h> /* HZ */ |
10 | 11 | ||
11 | extern void __delay(int loops); | 12 | #define MAX_UDELAY_MS 2 |
13 | #define UDELAY_MULT ((UL(2199023) * HZ) >> 11) | ||
14 | #define UDELAY_SHIFT 30 | ||
15 | |||
16 | #ifndef __ASSEMBLY__ | ||
17 | |||
18 | extern struct arm_delay_ops { | ||
19 | void (*delay)(unsigned long); | ||
20 | void (*const_udelay)(unsigned long); | ||
21 | void (*udelay)(unsigned long); | ||
22 | } arm_delay_ops; | ||
23 | |||
24 | #define __delay(n) arm_delay_ops.delay(n) | ||
12 | 25 | ||
13 | /* | 26 | /* |
14 | * This function intentionally does not exist; if you see references to | 27 | * This function intentionally does not exist; if you see references to |
@@ -23,22 +36,27 @@ extern void __bad_udelay(void); | |||
23 | * division by multiplication: you don't have to worry about | 36 | * division by multiplication: you don't have to worry about |
24 | * loss of precision. | 37 | * loss of precision. |
25 | * | 38 | * |
26 | * Use only for very small delays ( < 1 msec). Should probably use a | 39 | * Use only for very small delays ( < 2 msec). Should probably use a |
27 | * lookup table, really, as the multiplications take much too long with | 40 | * lookup table, really, as the multiplications take much too long with |
28 | * short delays. This is a "reasonable" implementation, though (and the | 41 | * short delays. This is a "reasonable" implementation, though (and the |
29 | * first constant multiplications gets optimized away if the delay is | 42 | * first constant multiplications gets optimized away if the delay is |
30 | * a constant) | 43 | * a constant) |
31 | */ | 44 | */ |
32 | extern void __udelay(unsigned long usecs); | 45 | #define __udelay(n) arm_delay_ops.udelay(n) |
33 | extern void __const_udelay(unsigned long); | 46 | #define __const_udelay(n) arm_delay_ops.const_udelay(n) |
34 | |||
35 | #define MAX_UDELAY_MS 2 | ||
36 | 47 | ||
37 | #define udelay(n) \ | 48 | #define udelay(n) \ |
38 | (__builtin_constant_p(n) ? \ | 49 | (__builtin_constant_p(n) ? \ |
39 | ((n) > (MAX_UDELAY_MS * 1000) ? __bad_udelay() : \ | 50 | ((n) > (MAX_UDELAY_MS * 1000) ? __bad_udelay() : \ |
40 | __const_udelay((n) * ((2199023U*HZ)>>11))) : \ | 51 | __const_udelay((n) * UDELAY_MULT)) : \ |
41 | __udelay(n)) | 52 | __udelay(n)) |
42 | 53 | ||
54 | /* Loop-based definitions for assembly code. */ | ||
55 | extern void __loop_delay(unsigned long loops); | ||
56 | extern void __loop_udelay(unsigned long usecs); | ||
57 | extern void __loop_const_udelay(unsigned long); | ||
58 | |||
59 | #endif /* __ASSEMBLY__ */ | ||
60 | |||
43 | #endif /* defined(_ARM_DELAY_H) */ | 61 | #endif /* defined(_ARM_DELAY_H) */ |
44 | 62 | ||