diff options
Diffstat (limited to 'arch/um/sys-x86_64/delay.c')
| -rw-r--r-- | arch/um/sys-x86_64/delay.c | 54 |
1 files changed, 42 insertions, 12 deletions
diff --git a/arch/um/sys-x86_64/delay.c b/arch/um/sys-x86_64/delay.c index dee5be66da82..f3fe1a688f7e 100644 --- a/arch/um/sys-x86_64/delay.c +++ b/arch/um/sys-x86_64/delay.c @@ -1,30 +1,60 @@ /* - * Copyright 2003 PathScale, Inc. - * Copied from arch/x86_64 + * Copyright (C) 2011 Richard Weinberger <richrd@nod.at> + * Mostly copied from arch/x86/lib/delay.c * - * Licensed under the GPL + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. */ #include <linux/module.h> +#include <linux/kernel.h> #include <linux/delay.h> -#include <asm/processor.h> #include <asm/param.h> void __delay(unsigned long loops) { - unsigned long i; + asm volatile( + "test %0,%0\n" + "jz 3f\n" + "jmp 1f\n" - for(i = 0; i < loops; i++) - cpu_relax(); + ".align 16\n" + "1: jmp 2f\n" + + ".align 16\n" + "2: dec %0\n" + " jnz 2b\n" + "3: dec %0\n" + + : /* we don't need output */ + : "a" (loops) + ); } +EXPORT_SYMBOL(__delay); -void __udelay(unsigned long usecs) +inline void __const_udelay(unsigned long xloops) { - unsigned long i, n; + int d0; - n = (loops_per_jiffy * HZ * usecs) / MILLION; - for(i=0;i<n;i++) - cpu_relax(); + xloops *= 4; + asm("mull %%edx" + : "=d" (xloops), "=&a" (d0) + : "1" (xloops), "0" + (loops_per_jiffy * (HZ/4))); + + __delay(++xloops); } +EXPORT_SYMBOL(__const_udelay); +void __udelay(unsigned long usecs) +{ + __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */ +} EXPORT_SYMBOL(__udelay); + +void __ndelay(unsigned long nsecs) +{ + __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */ +} +EXPORT_SYMBOL(__ndelay); |