mirror of https://gitee.com/openkylin/linux.git
50 lines
893 B
C
50 lines
893 B
C
/* delay.c: Delay loops for sparc64
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*
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* Copyright (C) 2004 David S. Miller <davem@redhat.com>
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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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void __delay(unsigned long loops)
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{
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__asm__ __volatile__(
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" b,pt %%xcc, 1f\n"
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" cmp %0, 0\n"
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" .align 32\n"
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"1:\n"
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" bne,pt %%xcc, 1b\n"
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" subcc %0, 1, %0\n"
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: "=&r" (loops)
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: "0" (loops)
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: "cc");
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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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