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linux/arch/m68k/include/asm/div64.h

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m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 12:50:08 +08:00
#ifndef _M68K_DIV64_H
#define _M68K_DIV64_H
m68k: handle presence of 64bit mul/div instructions cleanly The traditional 68000 processors and the newer reduced instruction set ColdFire processors do not support the 32*32->64 multiply or the 64/32->32 divide instructions. This is not a difference based on the presence of a hardware MMU or not. Create a new config symbol to mark that a CPU type doesn't support the longer multiply/divide instructions. Use this then as a basis for using the fast 64bit based divide (in div64.h) and for linking in the extra libgcc functions that may be required (mulsi3, divsi3, etc). Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2011-11-11 13:13:08 +08:00
#ifdef CONFIG_CPU_HAS_NO_MULDIV64
#include <asm-generic/div64.h>
#else
m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 12:50:08 +08:00
#include <linux/types.h>
/* n = n / base; return rem; */
#define do_div(n, base) ({ \
union { \
unsigned long n32[2]; \
unsigned long long n64; \
} __n; \
unsigned long __rem, __upper; \
\
__n.n64 = (n); \
if ((__upper = __n.n32[0])) { \
asm ("divul.l %2,%1:%0" \
: "=d" (__n.n32[0]), "=d" (__upper) \
: "d" (base), "0" (__n.n32[0])); \
} \
asm ("divu.l %2,%1:%0" \
: "=d" (__n.n32[1]), "=d" (__rem) \
: "d" (base), "1" (__upper), "0" (__n.n32[1])); \
(n) = __n.n64; \
__rem; \
})
m68k: handle presence of 64bit mul/div instructions cleanly The traditional 68000 processors and the newer reduced instruction set ColdFire processors do not support the 32*32->64 multiply or the 64/32->32 divide instructions. This is not a difference based on the presence of a hardware MMU or not. Create a new config symbol to mark that a CPU type doesn't support the longer multiply/divide instructions. Use this then as a basis for using the fast 64bit based divide (in div64.h) and for linking in the extra libgcc functions that may be required (mulsi3, divsi3, etc). Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2011-11-11 13:13:08 +08:00
#endif /* CONFIG_CPU_HAS_NO_MULDIV64 */
m68k: merge the mmu and non-mmu versions of div64.h Trivial merge of the mmu and non-mmu versions of div64.h Signed-off-by: Greg Ungerer <gerg@uclinux.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2009-02-06 12:50:08 +08:00
#endif /* _M68K_DIV64_H */