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* Merge commit 'v2.6.27-rc6' into timers/hpetIngo Molnar2008-09-141-6/+37
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| * x86: HPET: read back compare register before reading counterThomas Gleixner2008-09-061-0/+7
| | | | | | | | | | | | | | | | | | | | After fixing the u32 thinko I sill had occasional hickups on ATI chipsets with small deltas. There seems to be a delay between writing the compare register and the transffer to the internal register which triggers the interrupt. Reading back the value makes sure, that it hit the internal match register befor we compare against the counter value. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * x86: HPET fix moronic 32/64bit thinkoThomas Gleixner2008-09-061-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We use the HPET only in 32bit mode because: 1) some HPETs are 32bit only 2) on i386 there is no way to read/write the HPET atomic 64bit wide The HPET code unification done by the "moron of the year" did not take into account that unsigned long is different on 32 and 64 bit. This thinko results in a possible endless loop in the clockevents code, when the return comparison fails due to the 64bit/332bit unawareness. unsigned long cnt = (u32) hpet_read() + delta can wrap over 32bit. but the final compare will fail and return -ETIME causing endless loops. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * HPET: make minimum reprogramming delta usefulThomas Gleixner2008-09-051-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The minimum reprogramming delta was hardcoded in HPET ticks, which is stupid as it does not work with faster running HPETs. The C1E idle patches made this prominent on AMD/RS690 chipsets, where the HPET runs with 25MHz. Set it to 5us which seems to be a reasonable value and fixes the problems on the bug reporters machines. We have a further sanity check now in the clock events, which increases the delta when it is not sufficient. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br> Tested-by: Dmitry Nezhevenko <dion@inhex.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: hpet: workaround SB700 BIOSThomas Gleixner2008-08-141-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AMD SB700 based systems with spread spectrum enabled use a SMM based HPET emulation to provide proper frequency setting. The SMM code is initialized with the first HPET register access and takes some time to complete. During this time the config register reads 0xffffffff. We check for max. 1000 loops whether the config register reads a non 0xffffffff value to make sure that HPET is up and running before we go further. A counting loop is safe, as the HPET access takes thousands of CPU cycles. On non SB700 based machines this check is only done once and has no side effects. Based on a quirk patch from: crane cai <crane.cai@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | hpet: /dev/hpet - fixes and cleanupDavid Brownell2008-07-311-1/+5
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Minor /dev/hpet updates and bugfixes: * Remove dead code, mostly remnants of an incomplete/unusable kernel interface ... noted when addressing "sparse" warnings: + hpet_unregister() and a routine it calls + hpet_task and all references, including hpet_task_lock + hpet_data.hd_flags (and HPET_DATA_PLATFORM) * Correct and improve boot message: + displays *counter* (shared between comparators) bit width, not *timer* bit widths (which are often mixed) + relabel "timers" as "comparators"; this is less confusing, they are not independent like normal timers are (sigh) + display MHz not Hz; it's never less than 10 MHz. * Tighten and correct the userspace interface code + don't accidentally program comparators in 64-bit mode using 32-bit values ... always force comparators into 32-bit mode + provide the correct bit definition flagging comparators with periodic capability ... the ABI is unchanged * Update Documentation/hpet.txt + be more correct and current + expand description a bit + don't mention that now-gone kernel interface Plus, add a FIXME comment for something that could cause big trouble on systems with more capable HPETs than at least Intel seems to ship. It seems that few folk use this userspace interface; it's not very usable given the general lack of HPET IRQ routing. I'm told that the only real point of it any more is to mmap for fast timestamps; IMO that's handled better through the gettimeofday() vsyscall. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* rtc-cmos: avoid spurious irqsDavid Brownell2008-07-241-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | This fixes kernel http://bugzilla.kernel.org/show_bug.cgi?id=11112 (bogus RTC update IRQs reported) for rtc-cmos, in two ways: - When HPET is stealing the IRQs, use the first IRQ to grab the seconds counter which will be monitored (instead of using whatever was previously in that memory); - In sane IRQ handling modes, scrub out old IRQ status before enabling IRQs. That latter is done by tightening up IRQ handling for rtc-cmos everywhere, also ensuring that when HPET is used it's the only thing triggering IRQ reports to userspace; net object shrink. Also fix a bogus HPET message related to its RTC emulation. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Report-by: W Unruh <unruh@physics.ubc.ca> Cc: Andrew Victor <avictor.za@gmail.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: make 64bit hpet_set_mapping to use ioremap too, v2Yinghai Lu2008-07-141-16/+4
| | | | | | | keep the one for VSYSCALL_HPET Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: clean up computation of HPET .mult variablesCarlos R. Mafra2008-05-121-25/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While reading through the HPET code I realized that the computation of .mult variables could be done with less lines of code, resulting in a 1.6% text size saving for hpet.o So I propose the following patch, which applies against today's Linus -git tree. >From 0c6507e400e9ca5f7f14331e18f8c12baf75a9d3 Mon Sep 17 00:00:00 2001 From: Carlos R. Mafra <crmafra@ift.unesp.br> Date: Mon, 5 May 2008 19:38:53 -0300 The computation of clocksource_hpet.mult tmp = (u64)hpet_period << HPET_SHIFT; do_div(tmp, FSEC_PER_NSEC); clocksource_hpet.mult = (u32)tmp; can be streamlined if we note that it is equal to clocksource_hpet.mult = div_sc(hpet_period, FSEC_PER_NSEC, HPET_SHIFT); Furthermore, the computation of hpet_clockevent.mult uint64_t hpet_freq; hpet_freq = 1000000000000000ULL; do_div(hpet_freq, hpet_period); hpet_clockevent.mult = div_sc((unsigned long) hpet_freq, NSEC_PER_SEC, hpet_clockevent.shift); can also be streamlined with the observation that hpet_period and hpet_freq are inverse to each other (in proper units). So instead of computing hpet_freq and using (schematically) div_sc(hpet_freq, 10^9, shift) we use the trick of calling with the arguments in reverse order, div_sc(10^6, hpet_period, shift). The different power of ten is due to frequency being in Hertz (1/sec) and the period being in units of femtosecond. Explicitly, mult = (hpet_freq * 2^shift)/10^9 (before) mult = (10^6 * 2^shift)/hpet_period (after) because hpet_freq = 10^15/hpet_period. The comments in the code are also updated to reflect the changes. As a result, text data bss dec hex filename 2957 425 92 3474 d92 arch/x86/kernel/hpet.o 3006 425 92 3523 dc3 arch/x86/kernel/hpet.o.old a 1.6% reduction in text size. Signed-off-by: Carlos R. Mafra <crmafra@ift.unesp.br> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* hpet: fixIngo Molnar2008-04-301-2/+3
| | | | | | | | Al Viro pointed out that there's a missing readl() of timer->hpet_config, found by Sparse. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: cleanup div_sc() usageAkinobu Mita2008-04-261-1/+1
| | | | | | | 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>
* x86: revert assign IRQs to hpet timerThomas Gleixner2008-04-041-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commits: commit 37a47db8d7f0f38dac5acf5a13abbc8f401707fa Author: Balaji Rao <balajirrao@gmail.com> Date: Wed Jan 30 13:30:03 2008 +0100 x86: assign IRQs to HPET timers, fix and commit e3f37a54f690d3e64995ea7ecea08c5ab3070faf Author: Balaji Rao <balajirrao@gmail.com> Date: Wed Jan 30 13:30:03 2008 +0100 x86: assign IRQs to HPET timers have been identified to cause a regression on some platforms due to the assignement of legacy IRQs which makes the legacy devices connected to those IRQs disfunctional. Revert them. This fixes http://bugzilla.kernel.org/show_bug.cgi?id=10382 Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: hpet fix docbook commentPavel Machek2008-02-261-2/+2
| | | | | | Signed-off-by: Pavel Machek <Pavel@suse.cz> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* rtc: use the IRQ callback interface in (old) RTC driverBernhard Walle2008-01-301-2/+0
| | | | | | | | | | | | | | | | | | | | the previous patch in the old RTC driver. It also removes the direct rtc_interrupt() call from arch/x86/kernel/hpetc.c so that there's finally no (code) dependency to CONFIG_RTC in arch/x86/kernel/hpet.c. Because of this, it's possible to compile the drivers/char/rtc.ko driver as module and still use the HPET emulation functionality. This is also expressed in Kconfig. Signed-off-by: Bernhard Walle <bwalle@suse.de> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Robert Picco <Robert.Picco@hp.com> 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>
* x86, rtc: make CONFIG_HPET_EMULATE_RTC usable from modulesBernhard Walle2008-01-301-1/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | enabled, then interrupts don't work for the rtc-cmos driver which results in RTC_AIE*, RTC_PIE* and RTC_ALM being unusable. This affects hwclock from util-linux-ng at least on i386 since that uses RTC_PIE_ON. (For x86-64, a polling method is used for unknown reasons.) This patch series now 1. export the functions from arch/x86/kernel/hpet.c that the old char/rtc driver uses to work around that problem, 2. makes it possible to compile the old rtc driver as module, while still having CONFIG_HPET_EMULATE_RTC enabled and 3. makes use of the exported functions in (1) in the new rtc-cmos driver. This patch: This patch makes the RTC emulation functions in arch/x86/kernel/hpet.c usable for kernel modules. It - exports the functions (EXPORT_SYMBOL_GPL()), - adds an interface to register the interrupt callback function instead of using only a fixed callback function and - replaces the rtc_get_rtc_time() function which depends on CONFIG_RTC with a call to get_rtc_time() which is defined in include/asm-generic/rtc.h. The only dependency to CONFIG_RTC is the call to rtc_interrupt() which is removed by the next patch. After this, there's no (code) dependency of this functions to CONFIG_RTC=y any more. Signed-off-by: Bernhard Walle <bwalle@suse.de> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Robert Picco <Robert.Picco@hp.com> 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>
* x86: remove duplicate includesLucas Woods2008-01-301-1/+0
| | | | | | | | Signed-off-by: Lucas Woods <woodzy@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: assign IRQs to HPET timers, fixBalaji Rao2008-01-301-5/+5
| | | | | | | | | | | | | | Looks like IRQ 31 is assigned to timer 3, even without the patch! I wonder who wrote the number 31. But the manual says that it is zero by default. I think we should check whether the timer has been allocated an IRQ before proceeding to assign one to it. Here is a patch that does this. Signed-off-by: Balaji Rao <balajirrao@gmail.com> Tested-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: assign IRQs to HPET timersBalaji Rao2008-01-301-8/+5
| | | | | | | | | | | | | | | The userspace API for the HPET (see Documentation/hpet.txt) did not work. The HPET_IE_ON ioctl was failing as there was no IRQ assigned to the timer device. This patch fixes it by allocating IRQs to timer blocks in the HPET. arch/x86/kernel/hpet.c | 13 +++++-------- drivers/char/hpet.c | 45 ++++++++++++++++++++++++++++++++++++++------- include/linux/hpet.h | 2 +- 3 files changed, 44 insertions(+), 16 deletions(-) Signed-off-by: Balaji Rao <balajirrao@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* time: more timer related cleanupsPavel Machek2008-01-301-1/+2
| | | | | | | | | I was confused by FSEC = 10^15 NSEC statement, plus small whitespace fixes. When there's copyright, there should be GPL. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: fix RTC_AIE with CONFIG_HPET_EMULATE_RTCBernhard Walle2008-01-151-1/+1
| | | | | | | | | | | | | | | | | | | | In the current code, RTC_AIE doesn't work if the RTC relies on CONFIG_HPET_EMULATE_RTC because the code sets the RTC_AIE flag in hpet_set_rtc_irq_bit(). The interrupt handles does accidentally check for RTC_PIE and not RTC_AIE when comparing the time which was set in hpet_set_alarm_time(). I now verified on a test system here that without the patch applied, the attached test program fails on a system that has HPET with 2.6.24-rc7-default. That's not critical since I guess the problem has been there for several kernel releases, but as the fix is quite obvious. Configuration is CONFIG_RTC=y and CONFIG_HPET_EMULATE_RTC=y. Signed-off-by: Bernhard Walle <bwalle@suse.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: disable hpet on shutdownOGAWA Hirofumi2007-12-031-0/+14
| | | | | | | | | | | | | | | | If HPET was enabled by pci quirks, we use i8253 as initial clockevent because pci quirks doesn't run until pci is initialized. The above means the kernel (or something) is assuming HPET legacy replacement is disabled and can use i8253 at boot. If we used kexec, it isn't true. So, this patch disables HPET legacy replacement for kexec in machine_shutdown(). Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds2007-10-191-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (74 commits) fix do_sys_open() prototype sysfs: trivial: fix sysfs_create_file kerneldoc spelling mistake Documentation: Fix typo in SubmitChecklist. Typo: depricated -> deprecated Add missing profile=kvm option to Documentation/kernel-parameters.txt fix typo about TBI in e1000 comment proc.txt: Add /proc/stat field small documentation fixes Fix compiler warning in smount example program from sharedsubtree.txt docs/sysfs: add missing word to sysfs attribute explanation documentation/ext3: grammar fixes Documentation/java.txt: typo and grammar fixes Documentation/filesystems/vfs.txt: typo fix include/asm-*/system.h: remove unused set_rmb(), set_wmb() macros trivial copy_data_pages() tidy up Fix typo in arch/x86/kernel/tsc_32.c file link fix for Pegasus USB net driver help remove unused return within void return function Typo fixes retrun -> return x86 hpet.h: remove broken links ...
| * spelling fixes: arch/i386/Simon Arlott2007-10-201-1/+1
| | | | | | | | | | | | | | Spelling fixes in arch/i386/. Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Signed-off-by: Adrian Bunk <bunk@kernel.org>
* | x86: add force_hpet boot optionThomas Gleixner2007-10-191-0/+3
|/ | | | | | | | | add force_hpet boot option. (this will be useful to make the forced-enable quirks depend on.) Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: HPET force enable for ICH5Venki Pallipadi2007-10-121-1/+1
| | | | | | | | | | | | | | | force_enable hpet for ICH5. [ Build fixes from Andrew Morton ] Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: HPET try to activate force detected hpetVenki Pallipadi2007-10-121-2/+25
| | | | | | | | | | | | | | Enable HPET later during boot, after the force detect in PCI quirks. Also add a call to repeat the force enabling at resume time. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: HPET restructure hpet code for hpet force enableVenki Pallipadi2007-10-121-65/+83
| | | | | | | | | | | | | | | Restructure and rename legacy replacement mode HPET timer support. Just the code structural changes and should be zero functionality change. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* i386/x8664: cleanup the shared hpet codeChris Wright2007-10-121-5/+1
| | | | | | | | | | | Remove hpet_readl/writel from vsyscall.h, where it does not belong anyway. Use the hpet code itself. Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
* x86_64: remove now unused codeThomas Gleixner2007-10-121-0/+618
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>
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