1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_GENERIC_DELAY_H
3 #define __ASM_GENERIC_DELAY_H
4
5 /* Undefined functions to get compile-time errors */
6 extern void __bad_udelay(void);
7 extern void __bad_ndelay(void);
8
9 extern void __udelay(unsigned long usecs);
10 extern void __ndelay(unsigned long nsecs);
11 extern void __const_udelay(unsigned long xloops);
12 extern void __delay(unsigned long loops);
13
14 /*
15 * The weird n/20000 thing suppresses a "comparison is always false due to
16 * limited range of data type" warning with non-const 8-bit arguments.
17 */
18
19 /* 0x10c7 is 2**32 / 1000000 (rounded up) */
20 #define udelay(n) \
21 ({ \
22 if (__builtin_constant_p(n)) { \
23 if ((n) / 20000 >= 1) \
24 __bad_udelay(); \
25 else \
26 __const_udelay((n) * 0x10c7ul); \
27 } else { \
28 __udelay(n); \
29 } \
30 })
31
32 /* 0x5 is 2**32 / 1000000000 (rounded up) */
33 #define ndelay(n) \
34 ({ \
35 if (__builtin_constant_p(n)) { \
36 if ((n) / 20000 >= 1) \
37 __bad_ndelay(); \
38 else \
39 __const_udelay((n) * 5ul); \
40 } else { \
41 __ndelay(n); \
42 } \
43 })
44
45 #endif /* __ASM_GENERIC_DELAY_H */
46
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