xref: /openbmc/linux/arch/m68k/include/asm/div64.h (revision c900529f3d9161bfde5cca0754f83b4d3c3e0220)
1b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */
2d20f5aa3SGreg Ungerer #ifndef _M68K_DIV64_H
3d20f5aa3SGreg Ungerer #define _M68K_DIV64_H
4d20f5aa3SGreg Ungerer 
584f3fb7aSGreg Ungerer #ifdef CONFIG_CPU_HAS_NO_MULDIV64
684f3fb7aSGreg Ungerer #include <asm-generic/div64.h>
784f3fb7aSGreg Ungerer #else
8d20f5aa3SGreg Ungerer 
9d20f5aa3SGreg Ungerer #include <linux/types.h>
10d20f5aa3SGreg Ungerer 
11d20f5aa3SGreg Ungerer /* n = n / base; return rem; */
12d20f5aa3SGreg Ungerer 
13d20f5aa3SGreg Ungerer #define do_div(n, base) ({					\
14d20f5aa3SGreg Ungerer 	union {							\
15d20f5aa3SGreg Ungerer 		unsigned long n32[2];				\
16d20f5aa3SGreg Ungerer 		unsigned long long n64;				\
17d20f5aa3SGreg Ungerer 	} __n;							\
18d20f5aa3SGreg Ungerer 	unsigned long __rem, __upper;				\
19ea077b1bSAndreas Schwab 	unsigned long __base = (base);				\
20d20f5aa3SGreg Ungerer 								\
21d20f5aa3SGreg Ungerer 	__n.n64 = (n);						\
22d20f5aa3SGreg Ungerer 	if ((__upper = __n.n32[0])) {				\
23d20f5aa3SGreg Ungerer 		asm ("divul.l %2,%1:%0"				\
24d20f5aa3SGreg Ungerer 		     : "=d" (__n.n32[0]), "=d" (__upper)	\
25ea077b1bSAndreas Schwab 		     : "d" (__base), "0" (__n.n32[0]));		\
26d20f5aa3SGreg Ungerer 	}							\
27d20f5aa3SGreg Ungerer 	asm ("divu.l %2,%1:%0"					\
28d20f5aa3SGreg Ungerer 	     : "=d" (__n.n32[1]), "=d" (__rem)			\
29ea077b1bSAndreas Schwab 	     : "d" (__base), "1" (__upper), "0" (__n.n32[1]));	\
30d20f5aa3SGreg Ungerer 	(n) = __n.n64;						\
31d20f5aa3SGreg Ungerer 	__rem;							\
32d20f5aa3SGreg Ungerer })
33d20f5aa3SGreg Ungerer 
34*668a9202SArnd Bergmann /* defining this stops the unused helper function from being built */
35*668a9202SArnd Bergmann #define __div64_32 __div64_32
36*668a9202SArnd Bergmann 
3784f3fb7aSGreg Ungerer #endif /* CONFIG_CPU_HAS_NO_MULDIV64 */
38d20f5aa3SGreg Ungerer 
39d20f5aa3SGreg Ungerer #endif /* _M68K_DIV64_H */
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