[-mm PATCH 10/11] Time: i386 conversion part 4 - del timer_tsc.c

[john stultz]

Somehow the deletion of timer_tsc.c got dropped. This removes the file.

Signed-off-by: John Stultz <johnstul@xxxxxxxxxx>
 arch/i386/kernel/timers/timer_tsc.c |  439 ------------------------------------
 1 files changed, 439 deletions(-)

Index: mm-merge/arch/i386/kernel/timers/timer_tsc.c
===================================================================
--- mm-merge.orig/arch/i386/kernel/timers/timer_tsc.c
+++ /dev/null
@@ -1,439 +0,0 @@
-/*
- * This code largely moved from arch/i386/kernel/time.c.
- * See comments there for proper credits.
- *
- * 2004-06-25    Jesper Juhl
- *      moved mark_offset_tsc below cpufreq_delayed_get to avoid gcc 3.4
- *      failing to inline.
- */
-
-#include <linux/spinlock.h>
-#include <linux/init.h>
-#include <linux/timex.h>
-#include <linux/errno.h>
-#include <linux/cpufreq.h>
-#include <linux/string.h>
-#include <linux/jiffies.h>
-
-#include <asm/timer.h>
-#include <asm/io.h>
-/* processor.h for distable_tsc flag */
-#include <asm/processor.h>
-
-#include "io_ports.h"
-#include "mach_timer.h"
-
-#include <asm/hpet.h>
-#include <asm/i8253.h>
-
-#ifdef CONFIG_HPET_TIMER
-static unsigned long hpet_usec_quotient;
-static unsigned long hpet_last;
-static struct timer_opts timer_tsc;
-#endif
-
-static int use_tsc;
-/* Number of usecs that the last interrupt was delayed */
-static int delay_at_last_interrupt;
-
-static unsigned long last_tsc_low; /* lsb 32 bits of Time Stamp Counter */
-static unsigned long last_tsc_high; /* msb 32 bits of Time Stamp Counter */
-static unsigned long long monotonic_base;
-static seqlock_t monotonic_lock = SEQLOCK_UNLOCKED;
-
-/* Avoid compensating for lost ticks before TSCs are synched */
-static int detect_lost_ticks;
-static int __init start_lost_tick_compensation(void)
-{
-	detect_lost_ticks = 1;
-	return 0;
-}
-late_initcall(start_lost_tick_compensation);
-
-/* convert from cycles(64bits) => nanoseconds (64bits)
- *  basic equation:
- *		ns = cycles / (freq / ns_per_sec)
- *		ns = cycles * (ns_per_sec / freq)
- *		ns = cycles * (10^9 / (cpu_khz * 10^3))
- *		ns = cycles * (10^6 / cpu_khz)
- *
- *	Then we use scaling math (suggested by george@xxxxxxxxxx) to get:
- *		ns = cycles * (10^6 * SC / cpu_khz) / SC
- *		ns = cycles * cyc2ns_scale / SC
- *
- *	And since SC is a constant power of two, we can convert the div
- *  into a shift.
- *
- *  We can use khz divisor instead of mhz to keep a better percision, since
- *  cyc2ns_scale is limited to 10^6 * 2^10, which fits in 32 bits.
- *  (mathieu.desnoyers@xxxxxxxxxx)
- *
- *			-johnstul@xxxxxxxxxx "math is hard, lets go shopping!"
- */
-static unsigned long cyc2ns_scale; 
-#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */
-
-static inline void set_cyc2ns_scale(unsigned long cpu_khz)
-{
-	cyc2ns_scale = (1000000 << CYC2NS_SCALE_FACTOR)/cpu_khz;
-}
-
-static inline unsigned long long cycles_2_ns(unsigned long long cyc)
-{
-	return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR;
-}
-
-static int count2; /* counter for mark_offset_tsc() */
-
-/* Cached *multiplier* to convert TSC counts to microseconds.
- * (see the equation below).
- * Equal to 2^32 * (1 / (clocks per usec) ).
- * Initialized in time_init.
- */
-static unsigned long fast_gettimeoffset_quotient;
-
-static unsigned long get_offset_tsc(void)
-{
-	register unsigned long eax, edx;
-
-	/* Read the Time Stamp Counter */
-
-	rdtsc(eax,edx);
-
-	/* .. relative to previous jiffy (32 bits is enough) */
-	eax -= last_tsc_low;	/* tsc_low delta */
-
-	/*
-         * Time offset = (tsc_low delta) * fast_gettimeoffset_quotient
-         *             = (tsc_low delta) * (usecs_per_clock)
-         *             = (tsc_low delta) * (usecs_per_jiffy / clocks_per_jiffy)
-	 *
-	 * Using a mull instead of a divl saves up to 31 clock cycles
-	 * in the critical path.
-         */
-
-	__asm__("mull %2"
-		:"=a" (eax), "=d" (edx)
-		:"rm" (fast_gettimeoffset_quotient),
-		 "0" (eax));
-
-	/* our adjusted time offset in microseconds */
-	return delay_at_last_interrupt + edx;
-}
-
-static unsigned long long monotonic_clock_tsc(void)
-{
-	unsigned long long last_offset, this_offset, base;
-	unsigned seq;
-	
-	/* atomically read monotonic base & last_offset */
-	do {
-		seq = read_seqbegin(&monotonic_lock);
-		last_offset = ((unsigned long long)last_tsc_high<<32)|last_tsc_low;
-		base = monotonic_base;
-	} while (read_seqretry(&monotonic_lock, seq));
-
-	/* Read the Time Stamp Counter */
-	rdtscll(this_offset);
-
-	/* return the value in ns */
-	return base + cycles_2_ns(this_offset - last_offset);
-}
-
-static void delay_tsc(unsigned long loops)
-{
-	unsigned long bclock, now;
-	
-	rdtscl(bclock);
-	do
-	{
-		rep_nop();
-		rdtscl(now);
-	} while ((now-bclock) < loops);
-}
-
-#ifdef CONFIG_HPET_TIMER
-static void mark_offset_tsc_hpet(void)
-{
-	unsigned long long this_offset, last_offset;
- 	unsigned long offset, temp, hpet_current;
-
-	write_seqlock(&monotonic_lock);
-	last_offset = ((unsigned long long)last_tsc_high<<32)|last_tsc_low;
-	/*
-	 * It is important that these two operations happen almost at
-	 * the same time. We do the RDTSC stuff first, since it's
-	 * faster. To avoid any inconsistencies, we need interrupts
-	 * disabled locally.
-	 */
-	/*
-	 * Interrupts are just disabled locally since the timer irq
-	 * has the SA_INTERRUPT flag set. -arca
-	 */
-	/* read Pentium cycle counter */
-
-	hpet_current = hpet_readl(HPET_COUNTER);
-	rdtsc(last_tsc_low, last_tsc_high);
-
-	/* lost tick compensation */
-	offset = hpet_readl(HPET_T0_CMP) - hpet_tick;
-	if (unlikely(((offset - hpet_last) > hpet_tick) && (hpet_last != 0))
-					&& detect_lost_ticks) {
-		int lost_ticks = (offset - hpet_last) / hpet_tick;
-		jiffies_64 += lost_ticks;
-	}
-	hpet_last = hpet_current;
-
-	/* update the monotonic base value */
-	this_offset = ((unsigned long long)last_tsc_high<<32)|last_tsc_low;
-	monotonic_base += cycles_2_ns(this_offset - last_offset);
-	write_sequnlock(&monotonic_lock);
-
-	/* calculate delay_at_last_interrupt */
-	/*
-	 * Time offset = (hpet delta) * ( usecs per HPET clock )
-	 *             = (hpet delta) * ( usecs per tick / HPET clocks per tick)
-	 *             = (hpet delta) * ( hpet_usec_quotient ) / (2^32)
-	 * Where,
-	 * hpet_usec_quotient = (2^32 * usecs per tick)/HPET clocks per tick
-	 */
-	delay_at_last_interrupt = hpet_current - offset;
-	ASM_MUL64_REG(temp, delay_at_last_interrupt,
-			hpet_usec_quotient, delay_at_last_interrupt);
-}
-#endif
-
-static void mark_offset_tsc(void)
-{
-	unsigned long lost,delay;
-	unsigned long delta = last_tsc_low;
-	int count;
-	int countmp;
-	static int count1 = 0;
-	unsigned long long this_offset, last_offset;
-	static int lost_count = 0;
-
-	write_seqlock(&monotonic_lock);
-	last_offset = ((unsigned long long)last_tsc_high<<32)|last_tsc_low;
-	/*
-	 * It is important that these two operations happen almost at
-	 * the same time. We do the RDTSC stuff first, since it's
-	 * faster. To avoid any inconsistencies, we need interrupts
-	 * disabled locally.
-	 */
-
-	/*
-	 * Interrupts are just disabled locally since the timer irq
-	 * has the SA_INTERRUPT flag set. -arca
-	 */
-
-	/* read Pentium cycle counter */
-
-	rdtsc(last_tsc_low, last_tsc_high);
-
-	spin_lock(&i8253_lock);
-	outb_p(0x00, PIT_MODE);     /* latch the count ASAP */
-
-	count = inb_p(PIT_CH0);    /* read the latched count */
-	count |= inb(PIT_CH0) << 8;
-
-	/*
-	 * VIA686a test code... reset the latch if count > max + 1
-	 * from timer_pit.c - cjb
-	 */
-	if (count > LATCH) {
-		outb_p(0x34, PIT_MODE);
-		outb_p(LATCH & 0xff, PIT_CH0);
-		outb(LATCH >> 8, PIT_CH0);
-		count = LATCH - 1;
-	}
-
-	spin_unlock(&i8253_lock);
-
-	if (pit_latch_buggy) {
-		/* get center value of last 3 time lutch */
-		if ((count2 >= count && count >= count1)
-		    || (count1 >= count && count >= count2)) {
-			count2 = count1; count1 = count;
-		} else if ((count1 >= count2 && count2 >= count)
-			   || (count >= count2 && count2 >= count1)) {
-			countmp = count;count = count2;
-			count2 = count1;count1 = countmp;
-		} else {
-			count2 = count1; count1 = count; count = count1;
-		}
-	}
-
-	/* lost tick compensation */
-	delta = last_tsc_low - delta;
-	{
-		register unsigned long eax, edx;
-		eax = delta;
-		__asm__("mull %2"
-		:"=a" (eax), "=d" (edx)
-		:"rm" (fast_gettimeoffset_quotient),
-		 "0" (eax));
-		delta = edx;
-	}
-	delta += delay_at_last_interrupt;
-	lost = delta/(1000000/HZ);
-	delay = delta%(1000000/HZ);
-	if (lost >= 2 && detect_lost_ticks) {
-		jiffies_64 += lost-1;
-
-		/* sanity check to ensure we're not always losing ticks */
-		if (lost_count++ > 100) {
-			printk(KERN_WARNING "Losing too many ticks!\n");
-			printk(KERN_WARNING "TSC cannot be used as a timesource.  \n");
-			printk(KERN_WARNING "Possible reasons for this are:\n");
-			printk(KERN_WARNING "  You're running with Speedstep,\n");
-			printk(KERN_WARNING "  You don't have DMA enabled for your hard disk (see hdparm),\n");
-			printk(KERN_WARNING "  Incorrect TSC synchronization on an SMP system (see dmesg).\n");
-			printk(KERN_WARNING "Falling back to a sane timesource now.\n");
-
-			clock_fallback();
-		}
-	} else
-		lost_count = 0;
-	/* update the monotonic base value */
-	this_offset = ((unsigned long long)last_tsc_high<<32)|last_tsc_low;
-	monotonic_base += cycles_2_ns(this_offset - last_offset);
-	write_sequnlock(&monotonic_lock);
-
-	/* calculate delay_at_last_interrupt */
-	count = ((LATCH-1) - count) * TICK_SIZE;
-	delay_at_last_interrupt = (count + LATCH/2) / LATCH;
-
-	/* catch corner case where tick rollover occured
-	 * between tsc and pit reads (as noted when
-	 * usec delta is > 90% # of usecs/tick)
-	 */
-	if (lost && abs(delay - delay_at_last_interrupt) > (900000/HZ))
-		jiffies_64++;
-}
-
-static int __init init_tsc(char* override)
-{
-
-	/* check clock override */
-	if (override[0] && strncmp(override,"tsc",3)) {
-#ifdef CONFIG_HPET_TIMER
-		if (is_hpet_enabled()) {
-			printk(KERN_ERR "Warning: clock= override failed. Defaulting to tsc\n");
-		} else
-#endif
-		{
-			return -ENODEV;
-		}
-	}
-
-	/*
-	 * If we have APM enabled or the CPU clock speed is variable
-	 * (CPU stops clock on HLT or slows clock to save power)
-	 * then the TSC timestamps may diverge by up to 1 jiffy from
-	 * 'real time' but nothing will break.
-	 * The most frequent case is that the CPU is "woken" from a halt
-	 * state by the timer interrupt itself, so we get 0 error. In the
-	 * rare cases where a driver would "wake" the CPU and request a
-	 * timestamp, the maximum error is < 1 jiffy. But timestamps are
-	 * still perfectly ordered.
-	 * Note that the TSC counter will be reset if APM suspends
-	 * to disk; this won't break the kernel, though, 'cuz we're
-	 * smart.  See arch/i386/kernel/apm.c.
-	 */
- 	/*
- 	 *	Firstly we have to do a CPU check for chips with
- 	 * 	a potentially buggy TSC. At this point we haven't run
- 	 *	the ident/bugs checks so we must run this hook as it
- 	 *	may turn off the TSC flag.
- 	 *
- 	 *	NOTE: this doesn't yet handle SMP 486 machines where only
- 	 *	some CPU's have a TSC. Thats never worked and nobody has
- 	 *	moaned if you have the only one in the world - you fix it!
- 	 */
-
-	count2 = LATCH; /* initialize counter for mark_offset_tsc() */
-
-	if (cpu_has_tsc) {
-		unsigned long tsc_quotient;
-#ifdef CONFIG_HPET_TIMER
-		if (is_hpet_enabled() && hpet_use_timer) {
-			unsigned long result, remain;
-			printk("Using TSC for gettimeofday\n");
-			tsc_quotient = calibrate_tsc_hpet(NULL);
-			timer_tsc.mark_offset = &mark_offset_tsc_hpet;
-			/*
-			 * Math to calculate hpet to usec multiplier
-			 * Look for the comments at get_offset_tsc_hpet()
-			 */
-			ASM_DIV64_REG(result, remain, hpet_tick,
-					0, KERNEL_TICK_USEC);
-			if (remain > (hpet_tick >> 1))
-				result++; /* rounding the result */
-
-			hpet_usec_quotient = result;
-		} else
-#endif
-		{
-			tsc_quotient = calibrate_tsc();
-		}
-
-		if (tsc_quotient) {
-			fast_gettimeoffset_quotient = tsc_quotient;
-			use_tsc = 1;
-			/*
-			 *	We could be more selective here I suspect
-			 *	and just enable this for the next intel chips ?
-			 */
-			/* report CPU clock rate in Hz.
-			 * The formula is (10^6 * 2^32) / (2^32 * 1 / (clocks/us)) =
-			 * clock/second. Our precision is about 100 ppm.
-			 */
-			{	unsigned long eax=0, edx=1000;
-				__asm__("divl %2"
-		       		:"=a" (cpu_khz), "=d" (edx)
-        	       		:"r" (tsc_quotient),
-	                	"0" (eax), "1" (edx));
-				printk("Detected %u.%03u MHz processor.\n",
-					cpu_khz / 1000, cpu_khz % 1000);
-			}
-			set_cyc2ns_scale(cpu_khz);
-			return 0;
-		}
-	}
-	return -ENODEV;
-}
-
-static int tsc_resume(void)
-{
-	write_seqlock(&monotonic_lock);
-	/* Assume this is the last mark offset time */
-	rdtsc(last_tsc_low, last_tsc_high);
-#ifdef CONFIG_HPET_TIMER
-	if (is_hpet_enabled() && hpet_use_timer)
-		hpet_last = hpet_readl(HPET_COUNTER);
-#endif
-	write_sequnlock(&monotonic_lock);
-	return 0;
-}
-
-
-
-
-/************************************************************/
-
-/* tsc timer_opts struct */
-static struct timer_opts timer_tsc = {
-	.name = "tsc",
-	.mark_offset = mark_offset_tsc, 
-	.get_offset = get_offset_tsc,
-	.monotonic_clock = monotonic_clock_tsc,
-	.delay = delay_tsc,
-	.read_timer = read_timer_tsc,
-	.resume	= tsc_resume,
-};
-
-struct init_timer_opts __initdata timer_tsc_init = {
-	.init = init_tsc,
-	.opts = &timer_tsc,
-};
-
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