linux-stable-rt/arch/sparc64/lib/delay.c

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/* delay.c: Delay loops for sparc64
*
* Copyright (C) 2004 David S. Miller <davem@redhat.com>
*
* Based heavily upon x86 variant which is:
* Copyright (C) 1993 Linus Torvalds
* Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
*/
#include <linux/delay.h>
void __delay(unsigned long loops)
{
__asm__ __volatile__(
" b,pt %%xcc, 1f\n"
" cmp %0, 0\n"
" .align 32\n"
"1:\n"
" bne,pt %%xcc, 1b\n"
" subcc %0, 1, %0\n"
: "=&r" (loops)
: "0" (loops)
: "cc");
}
/* We used to multiply by HZ after shifting down by 32 bits
* but that runs into problems for higher values of HZ and
* slow cpus.
*/
void __const_udelay(unsigned long n)
{
n *= 4;
n *= (cpu_data(_smp_processor_id()).udelay_val * (HZ/4));
n >>= 32;
__delay(n + 1);
}
void __udelay(unsigned long n)
{
__const_udelay(n * 0x10c7UL);
}
void __ndelay(unsigned long n)
{
__const_udelay(n * 0x5UL);
}