1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_MATH64_H
3#define _LINUX_MATH64_H
4
5#include <linux/types.h>
6
7#ifdef __x86_64__
8static inline u64 mul_u64_u64_div64(u64 a, u64 b, u64 c)
9{
10	u64 q;
11
12	asm ("mulq %2; divq %3" : "=a" (q)
13				: "a" (a), "rm" (b), "rm" (c)
14				: "rdx");
15
16	return q;
17}
18#define mul_u64_u64_div64 mul_u64_u64_div64
19#endif
20
21#ifdef __SIZEOF_INT128__
22static inline u64 mul_u64_u32_shr(u64 a, u32 b, unsigned int shift)
23{
24	return (u64)(((unsigned __int128)a * b) >> shift);
25}
26
27#else
28
29#ifdef __i386__
30static inline u64 mul_u32_u32(u32 a, u32 b)
31{
32	u32 high, low;
33
34	asm ("mull %[b]" : "=a" (low), "=d" (high)
35			 : [a] "a" (a), [b] "rm" (b) );
36
37	return low | ((u64)high) << 32;
38}
39#else
40static inline u64 mul_u32_u32(u32 a, u32 b)
41{
42	return (u64)a * b;
43}
44#endif
45
46static inline u64 mul_u64_u32_shr(u64 a, u32 b, unsigned int shift)
47{
48	u32 ah, al;
49	u64 ret;
50
51	al = a;
52	ah = a >> 32;
53
54	ret = mul_u32_u32(al, b) >> shift;
55	if (ah)
56		ret += mul_u32_u32(ah, b) << (32 - shift);
57
58	return ret;
59}
60
61#endif	/* __SIZEOF_INT128__ */
62
63#ifndef mul_u64_u64_div64
64static inline u64 mul_u64_u64_div64(u64 a, u64 b, u64 c)
65{
66	u64 quot, rem;
67
68	quot = a / c;
69	rem = a % c;
70
71	return quot * b + (rem * b) / c;
72}
73#endif
74
75#endif /* _LINUX_MATH64_H */
76