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3763be32d5
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>
47 lines
889 B
C
47 lines
889 B
C
/* delay.c: Delay loops for sparc64
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*
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* Copyright (C) 2004, 2006 David S. Miller <davem@davemloft.net>
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*
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* Based heavily upon x86 variant which is:
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* Copyright (C) 1993 Linus Torvalds
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* Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
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*/
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#include <linux/delay.h>
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#include <asm/timer.h>
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void __delay(unsigned long loops)
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{
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unsigned long bclock, now;
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bclock = tick_ops->get_tick();
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do {
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now = tick_ops->get_tick();
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} while ((now-bclock) < loops);
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}
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/* We used to multiply by HZ after shifting down by 32 bits
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* but that runs into problems for higher values of HZ and
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* slow cpus.
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*/
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void __const_udelay(unsigned long n)
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{
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n *= 4;
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n *= (cpu_data(raw_smp_processor_id()).udelay_val * (HZ/4));
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n >>= 32;
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__delay(n + 1);
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}
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void __udelay(unsigned long n)
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{
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__const_udelay(n * 0x10c7UL);
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}
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void __ndelay(unsigned long n)
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{
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__const_udelay(n * 0x5UL);
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}
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