time: move PIT_TICK_RATE to linux/timex.h

PIT_TICK_RATE is currently defined in four architectures, but in three different places. While linux/timex.h is not the perfect place for it, it is still a reasonable replacement for those drivers that traditionally use asm/timex.h to get CLOCK_TICK_RATE and expect it to be the PIT frequency. Note that for Alpha, the actual value changed from 1193182UL to 1193180UL. This is unlikely to make a difference, and probably can only improve accuracy. There was a discussion on the correct value of CLOCK_TICK_RATE a few years ago, after which every existing instance was getting changed to 1193182. According to the specification, it should be 1193181.818181... Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Len Brown <lenb@kernel.org> Cc: john stultz <johnstul@us.ibm.com> Cc: Dmitry Torokhov <dtor@mail.ru> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
joolstorrentecalo · Jun 17, 2009 · 08604bd · 08604bd
1 parent 03347e2
commit 08604bd
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Showing 13 changed files with 12 additions and 21 deletions.
diff --git a/arch/alpha/include/asm/8253pit.h b/arch/alpha/include/asm/8253pit.h
@@ -1,10 +1,3 @@
 /*
  * 8253/8254 Programmable Interval Timer
  */
-
-#ifndef _8253PIT_H
-#define _8253PIT_H
-
-#define PIT_TICK_RATE 	1193180UL
-
-#endif
diff --git a/arch/alpha/kernel/sys_ruffian.c b/arch/alpha/kernel/sys_ruffian.c
@@ -14,6 +14,7 @@
 #include <linux/sched.h>
 #include <linux/pci.h>
 #include <linux/ioport.h>
+#include <linux/timex.h>
 #include <linux/init.h>
 
 #include <asm/ptrace.h>

diff --git a/arch/mips/include/asm/i8253.h b/arch/mips/include/asm/i8253.h
@@ -12,8 +12,6 @@
 #define PIT_CH0			0x40
 #define PIT_CH2			0x42
 
-#define PIT_TICK_RATE		1193182UL
-
 extern spinlock_t i8253_lock;
 
 extern void setup_pit_timer(void);

diff --git a/arch/powerpc/include/asm/8253pit.h b/arch/powerpc/include/asm/8253pit.h
@@ -1,10 +1,3 @@
-#ifndef _ASM_POWERPC_8253PIT_H
-#define _ASM_POWERPC_8253PIT_H
-
 /*
  * 8253/8254 Programmable Interval Timer
  */
-
-#define PIT_TICK_RATE	1193182UL
-
-#endif	/* _ASM_POWERPC_8253PIT_H */
diff --git a/arch/x86/include/asm/timex.h b/arch/x86/include/asm/timex.h
@@ -4,9 +4,7 @@
 #include <asm/processor.h>
 #include <asm/tsc.h>
 
-/* The PIT ticks at this frequency (in HZ): */
-#define PIT_TICK_RATE		1193182
-
+/* Assume we use the PIT time source for the clock tick */
 #define CLOCK_TICK_RATE		PIT_TICK_RATE
 
 #define ARCH_HAS_READ_CURRENT_TIMER

diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c
@@ -7,6 +7,7 @@
 #include <linux/spinlock.h>
 #include <linux/jiffies.h>
 #include <linux/module.h>
+#include <linux/timex.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/io.h>

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
@@ -9,6 +9,7 @@
 #include <linux/delay.h>
 #include <linux/clocksource.h>
 #include <linux/percpu.h>
+#include <linux/timex.h>
 
 #include <asm/hpet.h>
 #include <asm/timer.h>

diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
@@ -18,6 +18,7 @@
 
 #include <linux/acpi_pmtmr.h>
 #include <linux/clocksource.h>
+#include <linux/timex.h>
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/pci.h>

diff --git a/drivers/input/joystick/analog.c b/drivers/input/joystick/analog.c
@@ -35,7 +35,7 @@
 #include <linux/input.h>
 #include <linux/gameport.h>
 #include <linux/jiffies.h>
-#include <asm/timex.h>
+#include <linux/timex.h>
 
 #define DRIVER_DESC	"Analog joystick and gamepad driver"
 

diff --git a/drivers/input/misc/pcspkr.c b/drivers/input/misc/pcspkr.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/input.h>
 #include <linux/platform_device.h>
+#include <linux/timex.h>
 #include <asm/io.h>
 
 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");

diff --git a/include/linux/timex.h b/include/linux/timex.h
@@ -280,6 +280,9 @@ extern int do_adjtimex(struct timex *);
 
 int read_current_timer(unsigned long *timer_val);
 
+/* The clock frequency of the i8253/i8254 PIT */
+#define PIT_TICK_RATE 1193182ul
+
 #endif /* KERNEL */
 
 #endif /* LINUX_TIMEX_H */
diff --git a/sound/drivers/pcsp/pcsp.h b/sound/drivers/pcsp/pcsp.h
@@ -10,6 +10,7 @@
 #define __PCSP_H__
 
 #include <linux/hrtimer.h>
+#include <linux/timex.h>
 #if defined(CONFIG_MIPS) || defined(CONFIG_X86)
 /* Use the global PIT lock ! */
 #include <asm/i8253.h>

diff --git a/sound/oss/pas2_pcm.c b/sound/oss/pas2_pcm.c
@@ -17,7 +17,7 @@
 
 #include <linux/init.h>
 #include <linux/spinlock.h>
-#include <asm/timex.h>
+#include <linux/timex.h>
 #include "sound_config.h"
 
 #include "pas2.h"