Commit f59a48cf authored by John Stultz's avatar John Stultz Committed by David S. Miller

[PATCH] linux-2.5.41_timer-changes_A4 (3/3 - integration)

        This is the final part 3 of 3 of my timer-change patch. Part 3
integrates the moved code (from part 2) into the new infrastructure
(from part 1).
parent e8498001
......@@ -53,7 +53,7 @@ HEAD := arch/i386/kernel/head.o arch/i386/kernel/init_task.o
libs-y += arch/i386/lib/
core-y += arch/i386/kernel/ arch/i386/mm/ \
arch/i386/$(MACHINE)/
arch/i386/$(MACHINE)/ arch/i386/kernel/timers/
drivers-$(CONFIG_MATH_EMULATION) += arch/i386/math-emu/
drivers-$(CONFIG_PCI) += arch/i386/pci/
......
......@@ -53,6 +53,7 @@
#include <asm/mpspec.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
#include <asm/timer.h>
#include <linux/mc146818rtc.h>
#include <linux/timex.h>
......@@ -78,18 +79,10 @@ extern unsigned long wall_jiffies;
spinlock_t rtc_lock = SPIN_LOCK_UNLOCKED;
#define TICK_SIZE (tick_nsec / 1000)
spinlock_t i8253_lock = SPIN_LOCK_UNLOCKED;
EXPORT_SYMBOL(i8253_lock);
#ifndef CONFIG_X86_TSC
#else
#define do_gettimeoffset() do_fast_gettimeoffset()
#endif
struct timer_opts* timer;
/*
* This version of gettimeofday has microsecond resolution
......@@ -101,7 +94,7 @@ void do_gettimeofday(struct timeval *tv)
unsigned long usec, sec;
read_lock_irqsave(&xtime_lock, flags);
usec = do_gettimeoffset();
usec = timer->get_offset();
{
unsigned long lost = jiffies - wall_jiffies;
if (lost)
......@@ -129,7 +122,7 @@ void do_settimeofday(struct timeval *tv)
* wall time. Discover what correction gettimeofday() would have
* made, and then undo it!
*/
tv->tv_usec -= do_gettimeoffset();
tv->tv_usec -= timer->get_offset();
tv->tv_usec -= (jiffies - wall_jiffies) * (1000000 / HZ);
while (tv->tv_usec < 0) {
......@@ -295,7 +288,7 @@ void timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
*/
write_lock(&xtime_lock);
timer->mark_offset();
do_timer_interrupt(irq, NULL, regs);
......@@ -345,6 +338,7 @@ unsigned long get_cmos_time(void)
return mktime(year, mon, day, hour, min, sec);
}
/* XXX this driverfs stuff should probably go elsewhere later -john */
static struct sys_device device_i8253 = {
.name = "rtc",
.id = 0,
......@@ -368,5 +362,6 @@ void __init time_init(void)
xtime.tv_nsec = 0;
timer = select_timer();
time_init_hook();
}
#
# Makefile for x86 timers
#
obj-y := timer.o
obj-y += timer_tsc.o
obj-y += timer_pit.o
include $(TOPDIR)/Rules.make
......@@ -2,11 +2,17 @@
#include <asm/timer.h>
/* list of externed timers */
/* eg: extern struct timer_opts timer_XXX*/;
#ifndef CONFIG_X86_TSC
extern struct timer_opts timer_pit;
#endif
extern struct timer_opts timer_tsc;
/* list of timers, ordered by preference */
struct timer_opts* timers[] = {
/* eg: &timer_XXX */
&timer_tsc
#ifndef CONFIG_X86_TSC
,&timer_pit
#endif
};
#define NR_TIMERS (sizeof(timers)/sizeof(timers[0]))
......
/*
* This code largely moved from arch/i386/kernel/time.c.
* See comments there for proper credits.
*/
#include <linux/spinlock.h>
#include <linux/module.h>
#include <linux/device.h>
#include <asm/timer.h>
#include <asm/io.h>
extern spinlock_t i8259A_lock;
extern spinlock_t i8253_lock;
#include "do_timer.h"
static int init_pit(void)
{
return 1;
}
static void mark_offset_pit(void)
{
/* nothing needed */
}
/* This function must be called with interrupts disabled
* It was inspired by Steve McCanne's microtime-i386 for BSD. -- jrs
......@@ -31,7 +56,7 @@
* comp.protocols.time.ntp!
*/
static unsigned long do_slow_gettimeoffset(void)
static unsigned long get_offset_pit(void)
{
int count;
......@@ -94,4 +119,10 @@ static unsigned long do_slow_gettimeoffset(void)
return count;
}
static unsigned long (*do_gettimeoffset)(void) = do_slow_gettimeoffset;
/* tsc timer_opts struct */
struct timer_opts timer_pit = {
init: init_pit,
mark_offset: mark_offset_pit,
get_offset: get_offset_pit
};
/*
* This code largely moved from arch/i386/kernel/time.c.
* See comments there for proper credits.
*/
#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/timex.h>
#include <asm/timer.h>
#include <asm/io.h>
extern int x86_udelay_tsc;
extern spinlock_t i8253_lock;
static int use_tsc;
/* Number of usecs that the last interrupt was delayed */
static int delay_at_last_interrupt;
......@@ -10,7 +26,7 @@ static unsigned long last_tsc_low; /* lsb 32 bits of Time Stamp Counter */
*/
unsigned long fast_gettimeoffset_quotient;
static inline unsigned long do_fast_gettimeoffset(void)
static unsigned long get_offset_tsc(void)
{
register unsigned long eax, edx;
......@@ -39,10 +55,9 @@ static inline unsigned long do_fast_gettimeoffset(void)
return delay_at_last_interrupt + edx;
}
if (use_tsc)
{
static void mark_offset_tsc(void)
{
int count;
/*
* It is important that these two operations happen almost at
* the same time. We do the RDTSC stuff first, since it's
......@@ -68,7 +83,7 @@ if (use_tsc)
count = ((LATCH-1) - count) * TICK_SIZE;
delay_at_last_interrupt = (count + LATCH/2) / LATCH;
}
}
/* ------ Calibrate the TSC -------
......@@ -83,7 +98,6 @@ if (use_tsc)
#define CALIBRATE_LATCH (5 * LATCH)
#define CALIBRATE_TIME (5 * 1000020/HZ)
#ifdef CONFIG_X86_TSC
static unsigned long __init calibrate_tsc(void)
{
/* Set the Gate high, disable speaker */
......@@ -148,7 +162,6 @@ static unsigned long __init calibrate_tsc(void)
bad_ctc:
return 0;
}
#endif /* CONFIG_X86_TSC */
#ifdef CONFIG_CPU_FREQ
......@@ -196,12 +209,9 @@ static struct notifier_block time_cpufreq_notifier_block = {
#endif
#ifdef CONFIG_X86_TSC
extern int x86_udelay_tsc;
#endif
/*
static int init_tsc(void)
{
/*
* 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
......@@ -215,7 +225,6 @@ static struct notifier_block time_cpufreq_notifier_block = {
* to disk; this won't break the kernel, though, 'cuz we're
* smart. See arch/i386/kernel/apm.c.
*/
#ifdef CONFIG_X86_TSC
/*
* Firstly we have to do a CPU check for chips with
* a potentially buggy TSC. At this point we haven't run
......@@ -239,9 +248,6 @@ static struct notifier_block time_cpufreq_notifier_block = {
* and just enable this for the next intel chips ?
*/
x86_udelay_tsc = 1;
#ifndef do_gettimeoffset
do_gettimeoffset = do_fast_gettimeoffset;
#endif
/* report CPU clock rate in Hz.
* The formula is (10^6 * 2^32) / (2^32 * 1 / (clocks/us)) =
......@@ -257,6 +263,17 @@ static struct notifier_block time_cpufreq_notifier_block = {
#ifdef CONFIG_CPU_FREQ
cpufreq_register_notifier(&time_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
#endif
return 1;
}
}
#endif /* CONFIG_X86_TSC */
return 0;
}
/************************************************************/
/* tsc timer_opts struct */
struct timer_opts timer_tsc = {
init: init_tsc,
mark_offset: mark_offset_tsc,
get_offset: get_offset_tsc
};
......@@ -9,6 +9,6 @@ struct timer_opts{
/* called by gettimeofday. returns # ms since the last timer interrupt */
unsigned long (*get_offset)(void);
};
#define TICK_SIZE (tick_nsec / 1000)
struct timer_opts* select_timer(void);
#endif
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