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