1 /* 1
2 * Copyright (C) 2000, 2004, 2021 Maciej W. R
3 * Copyright (C) 2003, 07 Ralf Baechle (ralf@l
4 *
5 * This file is subject to the terms and condi
6 * License. See the file "COPYING" in the mai
7 * for more details.
8 */
9 #ifndef __ASM_DIV64_H
10 #define __ASM_DIV64_H
11
12 #include <asm/bitsperlong.h>
13
14 #if BITS_PER_LONG == 32
15
16 /*
17 * No traps on overflows for any of these...
18 */
19
20 #define do_div64_32(res, high, low, base) ({
21 unsigned long __cf, __tmp, __tmp2, __i
22 unsigned long __quot32, __mod32;
23
24 __asm__(
25 " .set push
26 " .set noat
27 " .set noreorder
28 " move %2, $0
29 " move %3, $0
30 " b 1f
31 " li %4, 0x21
32 "0:
33 " sll $1, %0, 0x1
34 " srl %3, %0, 0x1f
35 " or %0, $1, %5
36 " sll %1, %1, 0x1
37 " sll %2, %2, 0x1
38 "1:
39 " bnez %3, 2f
40 " sltu %5, %0, %z6
41 " bnez %5, 3f
42 "2:
43 " addiu %4, %4, -1
44 " subu %0, %0, %z6
45 " addiu %2, %2, 1
46 "3:
47 " bnez %4, 0b
48 " srl %5, %1, 0x1f
49 " .set pop"
50 : "=&r" (__mod32), "=&r" (__tmp),
51 "=&r" (__quot32), "=&r" (__cf),
52 "=&r" (__i), "=&r" (__tmp2)
53 : "Jr" (base), "" (high), "1" (low));
54
55 (res) = __quot32;
56 __mod32;
57 })
58
59 #define __div64_32(n, base) ({
60 unsigned long __upper, __low, __high,
61 unsigned long long __quot;
62 unsigned long long __div;
63 unsigned long __mod;
64
65 __div = (*n);
66 __radix = (base);
67
68 __high = __div >> 32;
69 __low = __div;
70
71 if (__high < __radix) {
72 __upper = __high;
73 __high = 0;
74 } else {
75 __upper = __high % __radix;
76 __high /= __radix;
77 }
78
79 __mod = do_div64_32(__low, __upper, __
80
81 __quot = __high;
82 __quot = __quot << 32 | __low;
83 (*n) = __quot;
84 __mod;
85 })
86
87 #endif /* BITS_PER_LONG == 32 */
88
89 #include <asm-generic/div64.h>
90
91 #endif /* __ASM_DIV64_H */
92
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