diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-arm/delay.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-arm/delay.h')
-rw-r--r-- | include/asm-arm/delay.h | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/include/asm-arm/delay.h b/include/asm-arm/delay.h new file mode 100644 index 000000000000..1704360e9699 --- /dev/null +++ b/include/asm-arm/delay.h | |||
@@ -0,0 +1,42 @@ | |||
1 | /* | ||
2 | * Copyright (C) 1995-2004 Russell King | ||
3 | * | ||
4 | * Delay routines, using a pre-computed "loops_per_second" value. | ||
5 | */ | ||
6 | #ifndef __ASM_ARM_DELAY_H | ||
7 | #define __ASM_ARM_DELAY_H | ||
8 | |||
9 | extern void __delay(int loops); | ||
10 | |||
11 | /* | ||
12 | * This function intentionally does not exist; if you see references to | ||
13 | * it, it means that you're calling udelay() with an out of range value. | ||
14 | * | ||
15 | * With currently imposed limits, this means that we support a max delay | ||
16 | * of 2000us and 671 bogomips | ||
17 | */ | ||
18 | extern void __bad_udelay(void); | ||
19 | |||
20 | /* | ||
21 | * division by multiplication: you don't have to worry about | ||
22 | * loss of precision. | ||
23 | * | ||
24 | * Use only for very small delays ( < 1 msec). Should probably use a | ||
25 | * lookup table, really, as the multiplications take much too long with | ||
26 | * short delays. This is a "reasonable" implementation, though (and the | ||
27 | * first constant multiplications gets optimized away if the delay is | ||
28 | * a constant) | ||
29 | */ | ||
30 | extern void __udelay(unsigned long usecs); | ||
31 | extern void __const_udelay(unsigned long); | ||
32 | |||
33 | #define MAX_UDELAY_MS 2 | ||
34 | |||
35 | #define udelay(n) \ | ||
36 | (__builtin_constant_p(n) ? \ | ||
37 | ((n) > (MAX_UDELAY_MS * 1000) ? __bad_udelay() : \ | ||
38 | __const_udelay((n) * 0x68dbul)) : \ | ||
39 | __udelay(n)) | ||
40 | |||
41 | #endif /* defined(_ARM_DELAY_H) */ | ||
42 | |||