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* [PATCH] Time: i386 Conversion - part 4: Remove Old timer_opts Codejohn stultz2006-06-261-439/+0
| | | | | | | | | | | | | Remove the old timers/timer_opts infrastructure which has been disabled. It is a fairly straightforward set of deletions Note that this does not provide any i386 clocksources, so you will only have the jiffies clocksource. To get full replacements for the code being removed here, the timeofday-clocks-i386 patch will be needed. Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Time: i386 Conversion - part 2: Rework TSC Supportjohn stultz2006-06-261-178/+0
| | | | | | | | | | | | | | | | | | | | | | | As part of the i386 conversion to the generic timekeeping infrastructure, this introduces a new tsc.c file. The code in this file replaces the TSC initialization, management and access code currently in timer_tsc.c (which will be removed) that we want to preserve. The code also introduces the following functionality: o tsc_khz: like cpu_khz but stores the TSC frequency on systems that do not change TSC frequency w/ CPU frequency o check/mark_tsc_unstable: accessor/modifier flag for TSC timekeeping usability o minor cleanups to calibration math. This patch also includes a one line __cpuinitdata fix from Zwane Mwaikambo. Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] timer TSC check suspend notifier changeShaohua Li2006-05-011-2/+2
| | | | | | | | | | | At suspend time, the TSC CPUFREQ_SUSPENDCHANGE notifier change might wrongly enable interrupt. cpufreq driver suspend/resume is in interrupt disabled environment. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] x86: mark cyc2ns_scale readmostlyRavikiran G Thirumalai2006-03-221-1/+1
| | | | | | | | | This variable is rarely written to. Mark the variable accordingly. Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org> Signed-off-by: Shai Fultheim <shai@scalex86.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreqLinus Torvalds2006-02-131-0/+5
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| * [CPUFREQ] Check for not initialized freq on cpufreq changesThomas Renninger2006-02-021-0/+5
| | | | | | | | | | | | | | | | | | | | Test for old_freq equals 0 to insure not to divide by 0: ______________________________________________ Check for not initialized freq on cpufreq changes Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* | [PATCH] disable lost tick compensation before TSCs are syncedjohn stultz2006-02-011-2/+12
|/ | | | | | | | | | | | | | | | Avoid lost tick compensation early in boot before the TSCs are synchronized. Currently timekeeping is enabled before the TSCs are synchronized, thus when the TSCs are synched (reset to zero), it appears that a number of lost ticks have occurred. This can cause premature expiry of timers and in extreme cases can cause the soft lockup detection to fire. This resolves issues reported by Andy Whitcroft as well as bug #5366 reported by Tim Mann. Signed-off-by: John Stultz <johnstul@us.ibm.com> Acked-by: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix cpu frequency detection in ↵Larry Finger2006-01-061-0/+2
| | | | | | | | | | | | | | | | | arch/i386/kernel/timers/timer_tsc.c::recalibrate_cpu_khz() When we re-calibrate the frequency, it is likely that an interrupt (as for example the main system clock) will be triggered by the system. Therefore the calibration may not be accurate. This will also provide a fix to bug #5266. Many thanks to Larry Finger for helping resolving this issue. Signed-off-by: Bruno Ducrot <ducrot@poupinou.org> Cc: john stultz <johnstul@us.ibm.com> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] i386 and x86_64 TSC set_cyc2ns_scale imprecisionMathieu Desnoyers2005-10-301-8/+13
| | | | | | | | | | | | | | | | | I just found out that some precision is unnecessarily lost in the arch/i386/kernel/timers/timer_tsc.c:set_cyc2ns_scale function. It uses a cpu_mhz parameter when it could use a cpu_khz. In the specific case of an Intel P4 running at 3001.171 Mhz, the truncation to 3001 Mhz leads to an imprecision of 19 microseconds per second : this is very sad for a timer with nearly nanosecond accuracy. Fix the x86_64 architecture too. Cc: george anzinger <george@mvista.com> Cc: john stultz <johnstul@us.ibm.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] add suspend/resume for timerShaohua Li2005-09-051-0/+14
| | | | | | | | | | | The timers lack .suspend/.resume methods. Because of this, jiffies got a big compensation after a S3 resume. And then softlockup watchdog reports an oops. This occured with HPET enabled, but it's also possible for other timers. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] x86: i8253/i8259A lock cleanupIngo Molnar2005-06-301-2/+1
| | | | | | | | Introduce proper declarations for i8253_lock and i8259A_lock. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] init call cleanupLi Shaohua2005-06-251-1/+1
| | | | | | | | | Trival patch for CPU hotplug. In CPU identify part, only did cleaup for intel CPUs. Need do for other CPUs if they support S3 SMP. Signed-off-by: Li Shaohua<shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] x86: cpu_khz type fixAndrew Morton2005-06-231-3/+4
| | | | | | | | | | x86_64's cpu_khz is unsigned int and there is no reason why x86 needs to use unsigned long. So make cpu_khz unsigned int on x86 as well. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Platform SMIs and their interferance with tsc based delay calibrationVenkatesh Pallipadi2005-06-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Issue: Current tsc based delay_calibration can result in significant errors in loops_per_jiffy count when the platform events like SMIs (System Management Interrupts that are non-maskable) are present. This could lead to potential kernel panic(). This issue is becoming more visible with 2.6 kernel (as default HZ is 1000) and on platforms with higher SMI handling latencies. During the boot time, SMIs are mostly used by BIOS (for things like legacy keyboard emulation). Description: The psuedocode for current delay calibration with tsc based delay looks like (0) Estimate a value for loops_per_jiffy (1) While (loops_per_jiffy estimate is accurate enough) (2) wait for jiffy transition (jiffy1) (3) Note down current tsc (tsc1) (4) loop until tsc becomes tsc1 + loops_per_jiffy (5) check whether jiffy changed since jiffy1 or not and refine loops_per_jiffy estimate Consider the following cases Case 1: If SMIs happen between (2) and (3) above, we can end up with a loops_per_jiffy value that is too low. This results in shorted delays and kernel can panic () during boot (Mostly at IOAPIC timer initialization timer_irq_works() as we don't have enough timer interrupts in a specified interval). Case 2: If SMIs happen between (3) and (4) above, then we can end up with a loops_per_jiffy value that is too high. And with current i386 code, too high lpj value (greater than 17M) can result in a overflow in delay.c:__const_udelay() again resulting in shorter delay and panic(). Solution: The patch below makes the calibration routine aware of asynchronous events like SMIs. We increase the delay calibration time and also identify any significant errors (greater than 12.5%) in the calibration and notify it to user. Patch below changes both i386 and x86-64 architectures to use this new and improved calibrate_delay_direct() routine. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [CPUFREQ] Recalibrate cpu_khz [2/2]Dave Jones2005-05-311-0/+20
| | | | | | | | | | Some cpufreq drivers (at that time, only powernow-k7) need to recalibrate the cpu_khz at runtime. Signed-off-by: Bruno Ducrot <ducrot@poupinou.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Dave Jones <davej@redhat.com>
* [PATCH] i386: fix hpet for systems that don't support legacy replacementjohn stultz2005-05-011-1/+1
| | | | | | | | | | | | | | | Currently the i386 HPET code assumes the entire HPET implementation from the spec is present. This breaks on boxes that do not implement the optional legacy timer replacement functionality portion of the spec. This patch, which is very similar to my x86-64 patch for the same issue, fixes the problem allowing i386 systems that cannot use the HPET for the timer interrupt and RTC to still use the HPET as a time source. I've tested this patch on a system systems without HPET, with HPET but without legacy timer replacement, as well as HPET with legacy timer replacement. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+560
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!