[PATCH 9/16] This patch add provisions for time related functions so they

Glauber de Oliveira Costa
2007-10-31T19:14:54Z

can be later replaced by paravirt versions.

it basically encloses {g,s}et_wallclock inside the
already existent functions update_persistent_clock and
read_persistent_clock, and defines {s,g}et_wallclock
to the core of such functions.

it also allow for a later-on-game time initialization, as done
by i386. Paravirt guests can set a function to do their own
initialization this way.

Signed-off-by: Glauber de Oliveira Costa <gcosta-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Steven Rostedt <rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org>
Acked-by: Jeremy Fitzhardinge <jeremy-8XJ3FbD+ij9l57MIdRCFDg@public.gmane.org>
---
arch/x86/kernel/time_64.c | 42 ++++++++++++++++++++++++++++--------------
include/asm-x86/time.h | 26 ++++++++++++++++++++++----
2 files changed, 50 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kernel/time_64.c b/arch/x86/kernel/time_64.c
index c821edc..85ec401 100644
--- a/arch/x86/kernel/time_64.c
+++ b/arch/x86/kernel/time_64.c
@@ -33,9 +33,12 @@
#include <acpi/acpi_bus.h>
#endif
#include <asm/i8253.h>
+#include <asm/arch_hooks.h>
#include <asm/pgtable.h>
#include <asm/vsyscall.h>
+#include <asm/time.h>
#include <asm/timex.h>
+#include <asm/timer.h>
#include <asm/proto.h>
#include <asm/hpet.h>
#include <asm/sections.h>
@@ -77,18 +80,12 @@ EXPORT_SYMBOL(profile_pc);
* sheet for details.
*/

-static int set_rtc_mmss(unsigned long nowtime)
+int do_set_rtc_mmss(unsigned long nowtime)
{
int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
unsigned char control, freq_select;

-/*
- * IRQs are disabled when we're called from the timer interrupt,
- * no need for spin_lock_irqsave()
- */
-
- spin_lock(&rtc_lock);

/*
* Tell the clock it's being set and stop it.
@@ -138,14 +135,22 @@ static int set_rtc_mmss(unsigned long nowtime)
CMOS_WRITE(control, RTC_CONTROL);
CMOS_WRITE(freq_select, RTC_FREQ_SELECT);

- spin_unlock(&rtc_lock);
-
return retval;
}

int update_persistent_clock(struct timespec now)
{
- return set_rtc_mmss(now.tv_sec);
+ int retval;
+
+/*
+ * IRQs are disabled when we're called from the timer interrupt,
+ * no need for spin_lock_irqsave()
+ */
+ spin_lock(&rtc_lock);
+ retval = set_wallclock(now.tv_sec);
+ spin_unlock(&rtc_lock);
+
+ return retval;
}

static irqreturn_t timer_event_interrupt(int irq, void *dev_id)
@@ -157,7 +162,7 @@ static irqreturn_t timer_event_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}

-unsigned long read_persistent_clock(void)
+unsigned long do_get_cmos_time(void)
{
unsigned int year, mon, day, hour, min, sec;
unsigned long flags;
@@ -208,10 +213,15 @@ unsigned long read_persistent_clock(void)
return mktime(year, mon, day, hour, min, sec);
}

+unsigned long read_persistent_clock(void)
+{
+ return get_wallclock();
+}
+
/* calibrate_cpu is used on systems with fixed rate TSCs to determine
* processor frequency */
#define TICK_COUNT 100000000
-static unsigned int __init tsc_calibrate_cpu_khz(void)
+unsigned long __init native_calculate_cpu_khz(void)
{
int tsc_start, tsc_now;
int i, no_ctr_free;
@@ -261,20 +271,23 @@ static struct irqaction irq0 = {
.name = "timer"
};

-void __init time_init(void)
+void __init hpet_time_init(void)
{
if (!hpet_enable())
setup_pit_timer();

setup_irq(0, &irq0);
+}

+void __init time_init(void)
+{
tsc_calibrate();

cpu_khz = tsc_khz;
if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&
boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
boot_cpu_data.x86 == 16)
- cpu_khz = tsc_calibrate_cpu_khz();
+ cpu_khz = calculate_cpu_khz();

if (unsynchronized_tsc())
mark_tsc_unstable("TSCs unsynchronized");
@@ -287,4 +300,5 @@ void __init time_init(void)
printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
cpu_khz / 1000, cpu_khz % 1000);
init_tsc_clocksource();
+ late_time_init = choose_time_init();
}
diff --git a/include/asm-x86/time.h b/include/asm-x86/time.h
index eac0113..0d18c78 100644
--- a/include/asm-x86/time.h
+++ b/include/asm-x86/time.h
@@ -1,6 +1,10 @@
-#ifndef _ASMi386_TIME_H
-#define _ASMi386_TIME_H
+#ifndef _ASMX86_TIME_H
+#define _ASMX86_TIME_H

+extern void (*late_time_init)(void);
+extern void hpet_time_init(void);
+
+#ifndef CONFIG_X86_64
#include <linux/efi.h>
#include "mach_time.h"

@@ -28,8 +32,22 @@ static inline int native_set_wallclock(unsigned long nowtime)
return retval;
}

-extern void (*late_time_init)(void);
-extern void hpet_time_init(void);
+#else
+extern unsigned long do_get_cmos_time(void);
+extern int do_set_rtc_mmss(unsigned long nowtime);
+extern void native_time_init_hook(void);
+
+static inline unsigned long native_get_wallclock(void)
+{
+ return do_get_cmos_time();
+}
+
+static inline int native_set_wallclock(unsigned long nowtime)
+{
+ return do_set_rtc_mmss(nowtime);
+}
+
+#endif

#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
--
1.4.4.2

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