linux/arch/sparc64/lib/delay.c
David S. Miller 3763be32d5 [SPARC64]: Define ARCH_HAS_READ_CURRENT_TIMER.
This gives more consistent bogomips and delay() semantics,
especially on sun4v.  It gives weird looking values though...

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:13:29 -08:00

47 lines
889 B
C

/* delay.c: Delay loops for sparc64
*
* Copyright (C) 2004, 2006 David S. Miller <davem@davemloft.net>
*
* 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>
#include <asm/timer.h>
void __delay(unsigned long loops)
{
unsigned long bclock, now;
bclock = tick_ops->get_tick();
do {
now = tick_ops->get_tick();
} while ((now-bclock) < loops);
}
/* 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(raw_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);
}