diff options
Diffstat (limited to 'include/asm-m68k/delay.h')
-rw-r--r-- | include/asm-m68k/delay.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/include/asm-m68k/delay.h b/include/asm-m68k/delay.h new file mode 100644 index 000000000000..5ed92851bc6f --- /dev/null +++ b/include/asm-m68k/delay.h | |||
@@ -0,0 +1,57 @@ | |||
1 | #ifndef _M68K_DELAY_H | ||
2 | #define _M68K_DELAY_H | ||
3 | |||
4 | #include <asm/param.h> | ||
5 | |||
6 | /* | ||
7 | * Copyright (C) 1994 Hamish Macdonald | ||
8 | * | ||
9 | * Delay routines, using a pre-computed "loops_per_jiffy" value. | ||
10 | */ | ||
11 | |||
12 | static inline void __delay(unsigned long loops) | ||
13 | { | ||
14 | __asm__ __volatile__ ("1: subql #1,%0; jcc 1b" | ||
15 | : "=d" (loops) : "0" (loops)); | ||
16 | } | ||
17 | |||
18 | extern void __bad_udelay(void); | ||
19 | |||
20 | /* | ||
21 | * Use only for very small delays ( < 1 msec). Should probably use a | ||
22 | * lookup table, really, as the multiplications take much too long with | ||
23 | * short delays. This is a "reasonable" implementation, though (and the | ||
24 | * first constant multiplications gets optimized away if the delay is | ||
25 | * a constant) | ||
26 | */ | ||
27 | static inline void __const_udelay(unsigned long xloops) | ||
28 | { | ||
29 | unsigned long tmp; | ||
30 | |||
31 | __asm__ ("mulul %2,%0:%1" | ||
32 | : "=d" (xloops), "=d" (tmp) | ||
33 | : "d" (xloops), "1" (loops_per_jiffy)); | ||
34 | __delay(xloops * HZ); | ||
35 | } | ||
36 | |||
37 | static inline void __udelay(unsigned long usecs) | ||
38 | { | ||
39 | __const_udelay(usecs * 4295); /* 2**32 / 1000000 */ | ||
40 | } | ||
41 | |||
42 | #define udelay(n) (__builtin_constant_p(n) ? \ | ||
43 | ((n) > 20000 ? __bad_udelay() : __const_udelay((n) * 4295)) : \ | ||
44 | __udelay(n)) | ||
45 | |||
46 | static inline unsigned long muldiv(unsigned long a, unsigned long b, | ||
47 | unsigned long c) | ||
48 | { | ||
49 | unsigned long tmp; | ||
50 | |||
51 | __asm__ ("mulul %2,%0:%1; divul %3,%0:%1" | ||
52 | : "=d" (tmp), "=d" (a) | ||
53 | : "d" (b), "d" (c), "1" (a)); | ||
54 | return a; | ||
55 | } | ||
56 | |||
57 | #endif /* defined(_M68K_DELAY_H) */ | ||