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060e352236
This patch cleans up the delay implementations a bit, makes the loops unoptimizable, and exports __udelay and __const_udelay. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
41 lines
701 B
C
41 lines
701 B
C
#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/delay.h>
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#include <asm/param.h>
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void __delay(unsigned long time)
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{
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/* Stolen from the i386 __loop_delay */
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int d0;
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__asm__ __volatile__(
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"\tjmp 1f\n"
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".align 16\n"
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"1:\tjmp 2f\n"
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".align 16\n"
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"2:\tdecl %0\n\tjns 2b"
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:"=&a" (d0)
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:"0" (time));
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}
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void __udelay(unsigned long usecs)
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{
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int i, n;
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n = (loops_per_jiffy * HZ * usecs) / MILLION;
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for(i=0;i<n;i++)
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cpu_relax();
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}
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EXPORT_SYMBOL(__udelay);
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void __const_udelay(unsigned long usecs)
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{
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int i, n;
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n = (loops_per_jiffy * HZ * usecs) / MILLION;
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for(i=0;i<n;i++)
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cpu_relax();
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}
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EXPORT_SYMBOL(__const_udelay);
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