xref: /OK3568_Linux_fs/kernel/arch/mips/include/asm/div64.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (C) 2000, 2004, 2021  Maciej W. Rozycki
3*4882a593Smuzhiyun  * Copyright (C) 2003, 07 Ralf Baechle (ralf@linux-mips.org)
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * This file is subject to the terms and conditions of the GNU General Public
6*4882a593Smuzhiyun  * License.  See the file "COPYING" in the main directory of this archive
7*4882a593Smuzhiyun  * for more details.
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun #ifndef __ASM_DIV64_H
10*4882a593Smuzhiyun #define __ASM_DIV64_H
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <asm/bitsperlong.h>
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun #if BITS_PER_LONG == 32
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun /*
17*4882a593Smuzhiyun  * No traps on overflows for any of these...
18*4882a593Smuzhiyun  */
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun #define do_div64_32(res, high, low, base) ({				\
21*4882a593Smuzhiyun 	unsigned long __cf, __tmp, __tmp2, __i;				\
22*4882a593Smuzhiyun 	unsigned long __quot32, __mod32;				\
23*4882a593Smuzhiyun 									\
24*4882a593Smuzhiyun 	__asm__(							\
25*4882a593Smuzhiyun 	"	.set	push					\n"	\
26*4882a593Smuzhiyun 	"	.set	noat					\n"	\
27*4882a593Smuzhiyun 	"	.set	noreorder				\n"	\
28*4882a593Smuzhiyun 	"	move	%2, $0					\n"	\
29*4882a593Smuzhiyun 	"	move	%3, $0					\n"	\
30*4882a593Smuzhiyun 	"	b	1f					\n"	\
31*4882a593Smuzhiyun 	"	 li	%4, 0x21				\n"	\
32*4882a593Smuzhiyun 	"0:							\n"	\
33*4882a593Smuzhiyun 	"	sll	$1, %0, 0x1				\n"	\
34*4882a593Smuzhiyun 	"	srl	%3, %0, 0x1f				\n"	\
35*4882a593Smuzhiyun 	"	or	%0, $1, %5				\n"	\
36*4882a593Smuzhiyun 	"	sll	%1, %1, 0x1				\n"	\
37*4882a593Smuzhiyun 	"	sll	%2, %2, 0x1				\n"	\
38*4882a593Smuzhiyun 	"1:							\n"	\
39*4882a593Smuzhiyun 	"	bnez	%3, 2f					\n"	\
40*4882a593Smuzhiyun 	"	 sltu	%5, %0, %z6				\n"	\
41*4882a593Smuzhiyun 	"	bnez	%5, 3f					\n"	\
42*4882a593Smuzhiyun 	"2:							\n"	\
43*4882a593Smuzhiyun 	"	 addiu	%4, %4, -1				\n"	\
44*4882a593Smuzhiyun 	"	subu	%0, %0, %z6				\n"	\
45*4882a593Smuzhiyun 	"	addiu	%2, %2, 1				\n"	\
46*4882a593Smuzhiyun 	"3:							\n"	\
47*4882a593Smuzhiyun 	"	bnez	%4, 0b					\n"	\
48*4882a593Smuzhiyun 	"	 srl	%5, %1, 0x1f				\n"	\
49*4882a593Smuzhiyun 	"	.set	pop"						\
50*4882a593Smuzhiyun 	: "=&r" (__mod32), "=&r" (__tmp),				\
51*4882a593Smuzhiyun 	  "=&r" (__quot32), "=&r" (__cf),				\
52*4882a593Smuzhiyun 	  "=&r" (__i), "=&r" (__tmp2)					\
53*4882a593Smuzhiyun 	: "Jr" (base), "0" (high), "1" (low));				\
54*4882a593Smuzhiyun 									\
55*4882a593Smuzhiyun 	(res) = __quot32;						\
56*4882a593Smuzhiyun 	__mod32;							\
57*4882a593Smuzhiyun })
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun #define __div64_32(n, base) ({						\
60*4882a593Smuzhiyun 	unsigned long __upper, __low, __high, __radix;			\
61*4882a593Smuzhiyun 	unsigned long long __quot;					\
62*4882a593Smuzhiyun 	unsigned long long __div;					\
63*4882a593Smuzhiyun 	unsigned long __mod;						\
64*4882a593Smuzhiyun 									\
65*4882a593Smuzhiyun 	__div = (*n);							\
66*4882a593Smuzhiyun 	__radix = (base);						\
67*4882a593Smuzhiyun 									\
68*4882a593Smuzhiyun 	__high = __div >> 32;						\
69*4882a593Smuzhiyun 	__low = __div;							\
70*4882a593Smuzhiyun 									\
71*4882a593Smuzhiyun 	if (__high < __radix) {						\
72*4882a593Smuzhiyun 		__upper = __high;					\
73*4882a593Smuzhiyun 		__high = 0;						\
74*4882a593Smuzhiyun 	} else {							\
75*4882a593Smuzhiyun 		__upper = __high % __radix;				\
76*4882a593Smuzhiyun 		__high /= __radix;					\
77*4882a593Smuzhiyun 	}								\
78*4882a593Smuzhiyun 									\
79*4882a593Smuzhiyun 	__mod = do_div64_32(__low, __upper, __low, __radix);		\
80*4882a593Smuzhiyun 									\
81*4882a593Smuzhiyun 	__quot = __high;						\
82*4882a593Smuzhiyun 	__quot = __quot << 32 | __low;					\
83*4882a593Smuzhiyun 	(*n) = __quot;							\
84*4882a593Smuzhiyun 	__mod;								\
85*4882a593Smuzhiyun })
86*4882a593Smuzhiyun 
87*4882a593Smuzhiyun #endif /* BITS_PER_LONG == 32 */
88*4882a593Smuzhiyun 
89*4882a593Smuzhiyun #include <asm-generic/div64.h>
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun #endif /* __ASM_DIV64_H */
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