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path: root/include/asm-powerpc/time.h
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2007-12-06[POWERPC] Fix hardware IRQ time accounting problem.Tony Breeds
The commit fa13a5a1f25f671d084d8884be96fc48d9b68275 (sched: restore deterministic CPU accounting on powerpc), unconditionally calls update_process_tick() in system context. In the deterministic accounting case this is the correct thing to do. However, in the non-deterministic accounting case we need to not do this, since doing this results in the time accounted as hardware irq time being artificially elevated. Also this collapses 2 consecutive '#ifdef CONFIG_VIRT_CPU_ACCOUNTING' checks in time.h into one for neatness. Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-11-08[POWERPC] Fix off-by-one error in setting decrementer on Book E/4xx (v2)Paul Mackerras
The decrementer in Book E and 4xx processors interrupts on the transition from 1 to 0, rather than on the 0 to -1 transition as on 64-bit server and 32-bit "classic" (6xx/7xx/7xxx) processors. At the moment we subtract 1 from the count of how many decrementer ticks are required before the next interrupt before putting it into the decrementer, which is correct for server/classic processors, but could possibly cause the interrupt to happen too early on Book E and 4xx if the timebase/decrementer frequency is low. This fixes the problem by making set_dec subtract 1 from the count for server and classic processors, instead of having the callers subtract 1. Since set_dec already had a bunch of ifdefs to handle different processor types, there is no net increase in ugliness. :) Note that calling set_dec(0) may not generate an interrupt on some processors. To make sure that decrementer_set_next_event always calls set_dec with an interval of at least 1 tick, we set min_delta_ns of the decrementer_clockevent to correspond to 2 ticks (2 rather than 1 to compensate for truncations in the conversions between ticks and ns). This also removes a redundant call to set the decrementer to 0x7fffffff - it was already set to that earlier in timer_interrupt. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-10-03[POWERPC] Implement clockevents driver for powerpcTony Breeds
This registers a clock event structure for the decrementer and turns on CONFIG_GENERIC_CLOCKEVENTS, which means that we now don't need most of timer_interrupt(), since the work is done in generic code. For secondary CPUs, their decrementer clockevent is registered when the CPU comes up (the generic code automatically removes the clockevent when the CPU goes down). Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-09-20Merge branch 'linux-2.6'Paul Mackerras
2007-09-19[POWERPC] Fix timekeeping on PowerPC 601Benjamin Herrenschmidt
Recent changes to the timekeeping code broke support for the PowerPC 601 processor which doesn't have the usual timebase facility but a slightly different thing called (yuck) the RTC. This fixes it, boot tested on an old 601 based PowerMac 7200. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-08-20[POWERPC] 40x decrementer fixesJosh Boyer
Allow generic_calibrate_decr to work for 40x platforms. Given that the hardware behavior is identical, this also changes the set_dec function to reload the PIT on 40x to match the behavior 44x currently has. Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2007-06-28[POWERPC] Move iSeries_tb_recal into its own late_initcall.Tony Breeds
Currently iSeries will recalibrate the cputime_factors in the first settimeofday() call. It seems the reason for doing this is to ensure a resaonable time delta after time_init(). On current kernels (with udev), this call is made 40-60 seconds into the boot process, by moving it to a late initcall it is called approximately 5 seconds after time_init() is called. This is sufficient to recalibrate the timebase. Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> CC: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-06-25[POWERPC] Fix stolen time for SMT without LPARMichael Neuling
For POWERPC, stolen time accounts for cycles lost to the hypervisor or PURR cycles attributed to the other SMT thread. Hence, when a PURR is available, we should still calculate stolen time, irrespective of being virtualised. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07[POWERPC] 8xx: powerpc port of core CPM PICVitaly Bordug
This covers common CPM access functions, CPM interrupt controller code, micropatch and a few compatibility things to kee the same driver base working with arch/ppc. This version is refined with all the comments (mostly PIC-related) addressed. Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-11-22[POWERPC] Revert "[POWERPC] Add powerpc get/set_rtc_time interface to new ↵Kim Phillips
generic rtc class" This reverts commit 7a69af63e788a324d162201a0b23df41bcf158dd. As advised by David Brownell: http://marc.theaimsgroup.com/?l=linux-kernel&m=116387226902131&w=2 Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-10-25[POWERPC] Cell timebase bug workaroundBenjamin Herrenschmidt
The Cell CPU timebase has an erratum. When reading the entire 64 bits of the timebase with one mftb instruction, there is a handful of cycles window during which one might read a value with the low order 32 bits already reset to 0x00000000 but the high order bits not yet incremeted by one. This fixes it by reading the timebase again until the low order 32 bits is no longer 0. That might introduce occasional latencies if hitting mftb just at the wrong time, but no more than 70ns on a cell blade, and that was considered acceptable. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-10-02[POWERPC] Add powerpc get/set_rtc_time interface to new generic rtc classKim Phillips
Add powerpc get/set_rtc_time interface to new generic rtc class. This abstracts rtc chip specific code from the platform code for rtc-over-i2c platforms. Specific RTC chip support is now configured under Device Drivers -> Real Time Clock. Setting time of day from the RTC on startup is also configurable. this time without the potentially platform breaking initcall. Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-08-30[PATCH] ppc32: fix last_jiffy time comparisonPaul Mackerras
This fixes a hang on ppc32. The problem was that I was comparing a 32-bit quantity with a 64-bit quantity, and consequently time wasn't advancing. This makes us use a 64-bit quantity on all platforms, which ends up simplifying the code since we can now get rid of the tb_last_stamp variable (which actually fixes another bug that Ben H and I noticed while going carefully through the code). This works fine on my G4 tibook. Let me know how it goes on your machines. Acked-by: Olaf Hering <olaf@aepfle.de> Acked-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28[POWERPC] update asm-powerpc/time.hStephen Rothwell
If we ever build a combined kernel including iSeries, then this will be needed. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-04-26Don't include linux/config.h from anywhere else in include/David Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-02-24powerpc: Implement accurate task and CPU time accountingPaul Mackerras
This implements accurate task and cpu time accounting for 64-bit powerpc kernels. Instead of accounting a whole jiffy of time to a task on a timer interrupt because that task happened to be running at the time, we now account time in units of timebase ticks according to the actual time spent by the task in user mode and kernel mode. We also count the time spent processing hardware and software interrupts accurately. This is conditional on CONFIG_VIRT_CPU_ACCOUNTING. If that is not set, we do tick-based approximate accounting as before. To get this accurate information, we read either the PURR (processor utilization of resources register) on POWER5 machines, or the timebase on other machines on * each entry to the kernel from usermode * each exit to usermode * transitions between process context, hard irq context and soft irq context in kernel mode * context switches. On POWER5 systems with shared-processor logical partitioning we also read both the PURR and the timebase at each timer interrupt and context switch in order to determine how much time has been taken by the hypervisor to run other partitions ("steal" time). Unfortunately, since we need values of the PURR on both threads at the same time to accurately calculate the steal time, and since we can only calculate steal time on a per-core basis, the apportioning of the steal time between idle time (time which we ceded to the hypervisor in the idle loop) and actual stolen time is somewhat approximate at the moment. This is all based quite heavily on what s390 does, and it uses the generic interfaces that were added by the s390 developers, i.e. account_system_time(), account_user_time(), etc. This patch doesn't add any new interfaces between the kernel and userspace, and doesn't change the units in which time is reported to userspace by things such as /proc/stat, /proc/<pid>/stat, getrusage(), times(), etc. Internally the various task and cpu times are stored in timebase units, but they are converted to USER_HZ units (1/100th of a second) when reported to userspace. Some precision is therefore lost but there should not be any accumulating error, since the internal accumulation is at full precision. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-13[PATCH] powerpc: Remove lppaca structure from the PACADavid Gibson
At present the lppaca - the structure shared with the iSeries hypervisor and phyp - is contained within the PACA, our own low-level per-cpu structure. This doesn't have to be so, the patch below removes it, making a separate array of lppaca structures. This saves approximately 500*NR_CPUS bytes of image size and kernel memory, because we don't need aligning gap between the Linux and hypervisor portions of every PACA. On the other hand it means an extra level of dereference in many accesses to the lppaca. The patch also gets rid of several places where we assign the paca address to a local variable for no particular reason. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-01merge filename and modify references to iseries/hv_call.hKelly Daly
Signed-off-by: Kelly Daly <kelly@au.ibm.com>
2005-10-23powerpc: Fix time code for 601 processorsPaul Mackerras
The 601 doesn't have the timebase register; instead it has an RTCL register that counts nanoseconds and wraps at 1000000000, and an RTCU register that counts seconds. This makes the necessary changes for the merged time code to use the RTCL/U registers when the kernel is running on a 601. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-22ppc64/powerpc: Fix time initialization on SMP systemsPaul Mackerras
This moves smp_space_timers from arch/ppc64/kernel/smp.c to arch/powerpc/kernel/time.c and makes it initialize last_jiffy[] instead of paca[].next_jiffy_update_tb, since last_jiffy[] is now what the time code uses. It also declares smp_space_timers in include/asm-powerpc/time.h and gets rid of an ifdef in div128_by_32. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-20powerpc: Fix some bugs in the new merged time codePaul Mackerras
I had the sense of the test for when to use the old 601-style RTC registers inverted. pmac_calibrate_decr and via_calibrate_decr weren't setting ppc_tb_freq, on which all the further calculations depended. Lastly, update_gtod was losing the top 32 bits of the new tb_to_xs value. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-20powerpc: Merge time.c and asm/time.h.Paul Mackerras
We now use the merged time.c for both 32-bit and 64-bit compilation with ARCH=powerpc, and for ARCH=ppc64, but not for ARCH=ppc32. This removes setup_default_decr (folds its function into time_init) and moves wakeup_decrementer into time.c. This also makes an asm-powerpc/rtc.h. Signed-off-by: Paul Mackerras <paulus@samba.org>