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@@ -1,128 +0,0 @@
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-/*
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- * Precise Delay Loops for x86-64
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- *
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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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- * The __delay function must _NOT_ be inlined as its execution time
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- * depends wildly on alignment on many x86 processors.
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- */
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-
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-#include <linux/module.h>
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-#include <linux/sched.h>
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-#include <linux/timex.h>
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-#include <linux/preempt.h>
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-#include <linux/delay.h>
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-#include <linux/init.h>
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-
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-#include <asm/delay.h>
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-#include <asm/msr.h>
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-
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-#ifdef CONFIG_SMP
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-#include <asm/smp.h>
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-#endif
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-
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-/* simple loop based delay: */
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-static void delay_loop(unsigned long loops)
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-{
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- asm volatile(
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- " test %0,%0 \n"
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- " jz 3f \n"
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- " jmp 1f \n"
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-
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- ".align 16 \n"
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- "1: jmp 2f \n"
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-
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- ".align 16 \n"
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- "2: dec %0 \n"
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- " jnz 2b \n"
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- "3: dec %0 \n"
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-
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- : /* we don't need output */
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- :"a" (loops)
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- );
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-}
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-
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-static void delay_tsc(unsigned long loops)
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-{
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- unsigned bclock, now;
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- int cpu;
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-
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- preempt_disable();
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- cpu = smp_processor_id();
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- rdtscl(bclock);
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- for (;;) {
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- rdtscl(now);
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- if ((now - bclock) >= loops)
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- break;
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-
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- /* Allow RT tasks to run */
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- preempt_enable();
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- rep_nop();
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- preempt_disable();
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-
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- /*
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- * It is possible that we moved to another CPU, and
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- * since TSC's are per-cpu we need to calculate
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- * that. The delay must guarantee that we wait "at
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- * least" the amount of time. Being moved to another
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- * CPU could make the wait longer but we just need to
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- * make sure we waited long enough. Rebalance the
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- * counter for this CPU.
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- */
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- if (unlikely(cpu != smp_processor_id())) {
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- loops -= (now - bclock);
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- cpu = smp_processor_id();
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- rdtscl(bclock);
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- }
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- }
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- preempt_enable();
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-}
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-
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-static void (*delay_fn)(unsigned long) = delay_loop;
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-
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-void use_tsc_delay(void)
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-{
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- delay_fn = delay_tsc;
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-}
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-
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-int __devinit read_current_timer(unsigned long *timer_value)
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-{
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- if (delay_fn == delay_tsc) {
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- rdtscll(*timer_value);
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- return 0;
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- }
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- return -1;
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-}
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-
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-void __delay(unsigned long loops)
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-{
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- delay_fn(loops);
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-}
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-EXPORT_SYMBOL(__delay);
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-
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-inline void __const_udelay(unsigned long xloops)
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-{
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- int d0;
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- xloops *= 4;
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- __asm__("mull %%edx"
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- :"=d" (xloops), "=&a" (d0)
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- :"1" (xloops), "0"
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- (cpu_data(raw_smp_processor_id()).loops_per_jiffy * (HZ/4)));
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-
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- __delay(++xloops);
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-}
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-
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-EXPORT_SYMBOL(__const_udelay);
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-
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-void __udelay(unsigned long usecs)
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-{
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- __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
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-}
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-EXPORT_SYMBOL(__udelay);
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-
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-void __ndelay(unsigned long nsecs)
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-{
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- __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
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-}
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-EXPORT_SYMBOL(__ndelay);
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