xref: /OK3568_Linux_fs/kernel/arch/m68k/include/asm/div64.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef _M68K_DIV64_H
3*4882a593Smuzhiyun #define _M68K_DIV64_H
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun #ifdef CONFIG_CPU_HAS_NO_MULDIV64
6*4882a593Smuzhiyun #include <asm-generic/div64.h>
7*4882a593Smuzhiyun #else
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <linux/types.h>
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun /* n = n / base; return rem; */
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #define do_div(n, base) ({					\
14*4882a593Smuzhiyun 	union {							\
15*4882a593Smuzhiyun 		unsigned long n32[2];				\
16*4882a593Smuzhiyun 		unsigned long long n64;				\
17*4882a593Smuzhiyun 	} __n;							\
18*4882a593Smuzhiyun 	unsigned long __rem, __upper;				\
19*4882a593Smuzhiyun 	unsigned long __base = (base);				\
20*4882a593Smuzhiyun 								\
21*4882a593Smuzhiyun 	__n.n64 = (n);						\
22*4882a593Smuzhiyun 	if ((__upper = __n.n32[0])) {				\
23*4882a593Smuzhiyun 		asm ("divul.l %2,%1:%0"				\
24*4882a593Smuzhiyun 		     : "=d" (__n.n32[0]), "=d" (__upper)	\
25*4882a593Smuzhiyun 		     : "d" (__base), "0" (__n.n32[0]));		\
26*4882a593Smuzhiyun 	}							\
27*4882a593Smuzhiyun 	asm ("divu.l %2,%1:%0"					\
28*4882a593Smuzhiyun 	     : "=d" (__n.n32[1]), "=d" (__rem)			\
29*4882a593Smuzhiyun 	     : "d" (__base), "1" (__upper), "0" (__n.n32[1]));	\
30*4882a593Smuzhiyun 	(n) = __n.n64;						\
31*4882a593Smuzhiyun 	__rem;							\
32*4882a593Smuzhiyun })
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun #endif /* CONFIG_CPU_HAS_NO_MULDIV64 */
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun #endif /* _M68K_DIV64_H */
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