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2009-08-21x86: Do not unregister PIT clocksource on PIT oneshot setup/shutdownThomas Gleixner
This basically reverts commit 1a0c009ac (x86: unregister PIT clocksource when PIT is disabled) because the problem which was tried to address with that patch has been solved by commit 3f68535ada (clocksource: sanity check sysfs clocksource changes). The problem addressed by the original patch is that PIT could be selected as clocksource after the system switched the PIT off or set the PIT into one shot mode which would result in complete timekeeping wreckage. Now with the sysfs sanity check in place PIT cannot be selected again when the system is in oneshot mode. The system will not switch to one shot mode as long as PIT is installed because PIT is not suitable for one shot. The shutdown case which happens when the lapic timer is installed is covered by the fact that init_pit_clocksource() is called after the lapic timer take over and then does not install the PIT clocksource at all. We should have done the sanity checks back then, but ... This also solves the locking problem which was reported vs. the clocksource rework. LKML-Reference: <new-submission> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-06-16time: move PIT_TICK_RATE to linux/timex.hArnd Bergmann
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>
2009-04-21clocksource: pass clocksource to read() callbackMagnus Damm
Pass clocksource pointer to the read() callback for clocksources. This allows us to share the callback between multiple instances. [hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods] [akpm@linux-foundation.org: cleanup] Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-21x86: i8253 cleanupJaswinder Singh Rajput
Impact: cleanup - fix various style problems - fix header file issues Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2008-12-13cpumask: convert struct clock_event_device to cpumask pointers.Rusty Russell
Impact: change calling convention of existing clock_event APIs struct clock_event_timer's cpumask field gets changed to take pointer, as does the ->broadcast function. Another single-patch change. For safety, we BUG_ON() in clockevents_register_device() if it's not set. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@elte.hu>
2008-04-26x86: cleanup div_sc() usageAkinobu Mita
Remove the magic number in the third argment of div_sc(). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26x86: cleanup clocksource_hz2mult usageAkinobu Mita
Remove the magic number in the second argument of clocksource_hz2mult() Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-13x86: pit_clockevent can be staticHarvey Harrison
arch/x86/kernel/i8253.c:98:27: warning: symbol 'pit_clockevent' was not declared. Should it be static? Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30x86: isolate PIC/PIT in/out callsAlan Cox
Rather than remove and/or mangle inb_p/outb_p we want to remove the use of them from inappropriate places. For the PIC/PIT this may eventually depend on 32/64bitism or similar so start by adding inb/outb_pit and inb/outb_pic so that we can make them use any scheme we settle on without disturbing the existing, correct (for ISA), port 0x80 usage. (eg we can make inb_pit use udelay without messing up inb_p). Floppy already does this for the fdc. That really only leaves the CMOS as a core logic item to tackle, and bits of parallel port handling in the chipset layers. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30mips, x86: optimize the i8259 code a bitRalf Baechle
The timer code always calls the clock_event_device set_net_event and set_mode methods with interrupts disabled, so no need to use spin_lock_irqsave / spin_unlock_irqrestore for those. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Acked-by:Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30x86: unregister PIT clocksource when PIT is disabledThomas Gleixner
The following scenario might leave PIT as a disfunctional clock source: PIT is registered as clocksource PM_TIMER is registered as clocksource and enables highres/dyntick mode PIT is switched to oneshot mode -> now the readout of PIT is bogus, but the user might select PIT via the sysfs override, which would break the box as the time readout is unusable. Unregister the PIT clocksource when the PIT clock event device is switched into shutdown / oneshot mode. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30clocksource: add unregister function to disable unusable clocksourcesThomas Gleixner
On x86 the PIT might become an unusable clocksource. Add an unregister function to provide a possibilty to remove the PIT from the list of available clock sources. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30x86: restrict PIT clocksource usageThomas Gleixner
PIT clocksource is registered unconditionally even when HPET is enabled or when PIT is replaced by the local APIC timer. In both cases PIT can not be used as it is stopped and the readout would be stale. Prevent registering PIT in those cases. patch depends on: x86: offer is_hpet_enabled() on !CONFIG_HPET_TIMER too Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-20spelling fixes: arch/i386/Simon Arlott
Spelling fixes in arch/i386/. Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-13Delete filenames in comments.Dave Jones
Since the x86 merge, lots of files that referenced their own filenames are no longer correct. Rather than keep them up to date, just delete them, as they add no real value. Additionally: - fix up comment formatting in scx200_32.c - Remove a credit from myself in setup_64.c from a time when we had no SCM - remove longwinded history from tsc_32.c which can be figured out from git. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-12x86_64: remove now unused codeThomas Gleixner
Remove the unused code after the switch to clock events. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>