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* x86: hpet: fix periodic mode programming on AMD 81xxAndreas Herrmann2009-04-221-1/+17
| | | | | | | | | | | | | | | | | | | | | | | (See http://bugzilla.kernel.org/show_bug.cgi?id=12961) It partially reverts commit c23e253e67c9d8a91a0ffa33c1f571a17f0a2403 (x86: hpet: stop HPET_COUNTER when programming periodic mode) HPET on AMD 81xx chipset needs a second write (with HPET_TN_SETVAL cleared) to T0_CMP register to set the period in periodic mode. With this patch HPET_COUNTER is still stopped but not reset when HPET is programmed in periodic mode. This should help to avoid races when HPET is programmed in periodic mode and fixes a boot time hang that I've observed on a machine when using 1000HZ. [ Impact: fix boot time hang on machines with AMD 81xx chipset ] Reported-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Tested-by: Jeff Mahoney <jeffm@suse.com> LKML-Reference: <20090421180037.GA2763@alberich.amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* clocksource: pass clocksource to read() callbackMagnus Damm2009-04-211-3/+3
| | | | | | | | | | | | | | 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>
* x86: hpet: stop HPET_COUNTER when programming periodic modeAndreas Herrmann2009-02-221-10/+3
| | | | | | | | | | | | | | | | | | Impact: fix system hang on some systems operating with HZ_1000 On a system that stalled with HZ_1000, the first value written to T0_CMP (when the main counter was not stopped) did not trigger an interrupt. Instead after the main counter wrapped around (after several minutes) an interrupt was triggered and afterwards the periodic interrupt took effect. This can be fixed by implementing HPET spec recommendation for programming the periodic mode (i.e. stopping the main counter). Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Mark Hounschell <markh@compro.net> Cc: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: hpet: provide separate functions to stop and start the counterAndreas Herrmann2009-02-221-6/+16
| | | | | | | | | By splitting up existing hpet_start_counter function. Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Mark Hounschell <markh@compro.net> Cc: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: hpet: print HPET registers during setup (if hpet=verbose is used)Andreas Herrmann2009-02-221-0/+45
| | | | | | | Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Mark Hounschell <markh@compro.net> Cc: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds2009-02-171-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, vm86: fix preemption bug x86, olpc: fix model detection without OFW x86, hpet: fix for LS21 + HPET = boot hang x86: CPA avoid repeated lazy mmu flush x86: warn if arch_flush_lazy_mmu_cpu is called in preemptible context x86/paravirt: make arch_flush_lazy_mmu/cpu disable preemption x86, pat: fix warn_on_once() while mapping 0-1MB range with /dev/mem x86/cpa: make sure cpa is safe to call in lazy mmu mode x86, ptrace, mm: fix double-free on race
| * x86, hpet: fix for LS21 + HPET = boot hangjohn stultz2009-02-131-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Between 2.6.23 and 2.6.24-rc1 a change was made that broke IBM LS21 systems that had the HPET enabled in the BIOS, resulting in boot hangs for x86_64. Specifically commit b8ce33590687888ebb900d09557b8807c4539022, which merges the i386 and x86_64 HPET code. Prior to this commit, when we setup the HPET timers in x86_64, we did the following: hpet_writel(HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL | HPET_TN_32BIT, HPET_T0_CFG); However after the i386/x86_64 HPET merge, we do the following: cfg = hpet_readl(HPET_Tn_CFG(timer)); cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL | HPET_TN_32BIT; hpet_writel(cfg, HPET_Tn_CFG(timer)); However on LS21s with HPET enabled in the BIOS, the HPET_T0_CFG register boots with Level triggered interrupts (HPET_TN_LEVEL) enabled. This causes the periodic interrupt to be not so periodic, and that results in the boot time hang I reported earlier in the delay calibration. My fix: Always disable HPET_TN_LEVEL when setting up periodic mode. Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: clean up hpet timer reinitPavel Emelyanov2009-02-061-2/+10
| | | | | | | | | | | | | | | | | | | | | | Implement Linus's suggestion: introduce the hpet_cnt_ahead() helper function to compare hpet time values - like other wrapping counter comparisons are abstracted away elsewhere. (jiffies, ktime_t, etc.) Reported-by: Kirill Korotaev <dev@openvz.org> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: fix hpet timer reinit for x86_64Pavel Emelyanov2009-02-051-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | There's a small problem with hpet_rtc_reinit function - it checks for the: hpet_readl(HPET_COUNTER) - hpet_t1_cmp > 0 to continue increasing both the HPET_T1_CMP (register) and the hpet_t1_cmp (variable). But since the HPET_COUNTER is always 32-bit, if the hpet_t1_cmp is 64-bit this condition will always be FALSE once the latter hits the 32-bit boundary, and we can have a situation, when we don't increase the HPET_T1_CMP register high enough. The result - timer stops ticking, since HPET_T1_CMP becomes less, than the COUNTER and never increased again. The solution is (based on Linus's suggestion) to not compare 64-bits (on 64-bit x86), but to do the comparison on 32-bit signed integers. Reported-by: Kirill Korotaev <dev@openvz.org> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* debugobjects: add and use INIT_WORK_ON_STACKThomas Gleixner2009-01-221-1/+2
| | | | | | | | | | | | Impact: Fix debugobjects warning debugobject enabled kernels spit out a warning in hpet code due to a workqueue which is initialized on stack. Add INIT_WORK_ON_STACK() which calls init_timer_on_stack() and use it in hpet. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Merge branch 'cpus4096-for-linus-2' of ↵Linus Torvalds2009-01-021-4/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits) x86: export vector_used_by_percpu_irq x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and() sched: nominate preferred wakeup cpu, fix x86: fix lguest used_vectors breakage, -v2 x86: fix warning in arch/x86/kernel/io_apic.c sched: fix warning in kernel/sched.c sched: move test_sd_parent() to an SMP section of sched.h sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0 sched: activate active load balancing in new idle cpus sched: bias task wakeups to preferred semi-idle packages sched: nominate preferred wakeup cpu sched: favour lower logical cpu number for sched_mc balance sched: framework for sched_mc/smt_power_savings=N sched: convert BALANCE_FOR_xx_POWER to inline functions x86: use possible_cpus=NUM to extend the possible cpus allowed x86: fix cpu_mask_to_apicid_and to include cpu_online_mask x86: update io_apic.c to the new cpumask code x86: Introduce topology_core_cpumask()/topology_thread_cpumask() x86: xen: use smp_call_function_many() x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c ... Fixed up trivial conflict in kernel/time/tick-sched.c manually
| * cpumask: convert struct clock_event_device to cpumask pointers.Rusty Russell2008-12-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * cpumask: make irq_set_affinity() take a const struct cpumaskRusty Russell2008-12-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: change existing irq_chip API Not much point with gentle transition here: the struct irq_chip's setaffinity method signature needs to change. Fortunately, not widely used code, but hits a few architectures. Note: In irq_select_affinity() I save a temporary in by mangling irq_desc[irq].affinity directly. Ingo, does this break anything? (Folded in fix from KOSAKI Motohiro) Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Grant Grundler <grundler@parisc-linux.org> Acked-by: Ingo Molnar <mingo@redhat.com> Cc: ralf@linux-mips.org Cc: grundler@parisc-linux.org Cc: jeremy@xensource.com Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
* | Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2008-12-301-3/+4
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimers: fix warning in kernel/hrtimer.c x86: make sure we really have an hpet mapping before using it x86: enable HPET on Fujitsu u9200 linux/timex.h: cleanup for userspace posix-timers: simplify de_thread()->exit_itimers() path posix-timers: check ->it_signal instead of ->it_pid to validate the timer posix-timers: use "struct pid*" instead of "struct task_struct*" nohz: suppress needless timer reprogramming clocksource, acpi_pm.c: put acpi_pm_read_slow() under CONFIG_PCI nohz: no softirq pending warnings for offline cpus hrtimer: removing all ur callback modes, fix hrtimer: removing all ur callback modes, fix hotplug hrtimer: removing all ur callback modes x86: correct link to HPET timer specification rtc-cmos: export second NVRAM bank Fixed up conflicts in sound/drivers/pcsp/pcsp.c and sound/core/hrtimer.c manually.
| * | x86: make sure we really have an hpet mapping before using itJeremy Fitzhardinge2008-12-161-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: prepare the hpet code for Xen dom0 booting When booting in Xen dom0, the hpet isn't really accessible, so make sure the mapping is non-NULL before use. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86: enable HPET on Fujitsu u9200Janne Kulmala2008-12-161-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | Impact: auto-enable HPET on Fujitsu u9200 HPET timer is listed in the ACPI table, but needs a quirk entry in order to work. Unfortunately, the quirk code runs after first HPET hpet_enable() which has already determined that the timer doesn't work (reads 0xFFFFFFFF). This patch allows hpet_enable() to be called again after running the quirk code. Signed-off-by: Janne Kulmala <janne.t.kulmala@tut.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: fix unused variable warning in arch/x86/kernel/hpet.cIngo Molnar2008-11-251-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | Impact: fix build warning this warning: arch/x86/kernel/hpet.c:36: warning: ‘hpet_num_timers’ defined but not used Triggers because hpet_num_timers is unused in the !CONFIG_PCI_MSI case. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: HPET: fix sparse warningHannes Eder2008-11-231-1/+1
|/ | | | | | | | | | | | Impact: make global variable static Fix this sparse warning: arch/x86/kernel/hpet.c:36:18: warning: symbol 'hpet_num_timers' was not declared. Should it be static? Signed-off-by: Hannes Eder <hannes@hanneseder.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: HPET: enter hpet_interrupt_handler with interrupts disabledMatt Fleming2008-11-101-1/+1
| | | | | | | | | | | | | Some functions that may be called from this handler require that interrupts are disabled. Also, combining IRQF_DISABLED and IRQF_SHARED does not reliably disable interrupts in a handler, so remove IRQF_SHARED from the irq flags (this irq is not shared anyway). Signed-off-by: Matt Fleming <mjf@gentoo.org> Cc: mingo@elte.hu Cc: venkatesh.pallipadi@intel.com Cc: "Will Newton" <will.newton@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: HPET: read from HPET_Tn_CMP() not HPET_T0_CMPMatt Fleming2008-11-101-1/+1
| | | | | | | | | | | | In hpet_next_event() we check that the value we just wrote to HPET_Tn_CMP(timer) has reached the chip. Currently, we're checking that the value we wrote to HPET_Tn_CMP(timer) is in HPET_T0_CMP, which, if timer is anything other than timer 0, is likely to fail. Signed-off-by: Matt Fleming <mjf@gentoo.org> Cc: mingo@elte.hu Cc: venkatesh.pallipadi@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: HPET: convert WARN_ON to WARN_ON_ONCEMatt Fleming2008-11-101-1/+1
| | | | | | | | | | | It is possible to flood the console with call traces if the WARN_ON condition is true because of the frequency with which this function is called. Signed-off-by: Matt Fleming <mjf@gentoo.org> Cc: mingo@elte.hu Cc: venkatesh.pallipadi@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* hpet: clean up warningVenki Pallipadi2008-10-161-22/+35
| | | | | | | | | | | Fix the below compile warnings due to recent HPET MSI changes arch/x86/kernel/hpet.c:48: warning: 'hpet_devs' defined but not used arch/x86/kernel/hpet.c:50: warning: 'per_cpu__cpu_hpet_dev' defined but not used Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: print out irq nr for msi/ht, v3Yinghai Lu2008-10-161-0/+3
| | | | | | | | | | v2: fix hpet compiling error v3: Bjorn want to use dev_printk instead Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: fix HPET compiler error when not using CONFIG_PCI_MSISteven Noonan2008-10-161-0/+4
| | | | | | | Added dummy function for hpet_setup_msi_irq(). Signed-off-by: Steven Noonan <steven@uplinklabs.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: using HPET in MSI mode and setting up per CPU HPET timers, fixVenki Pallipadi2008-10-161-9/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Sat, Sep 06, 2008 at 06:03:53AM -0700, Ingo Molnar wrote: > > it crashes two testsystems, the fault on a NULL pointer in hpet init, > with: > > initcall print_all_ICs+0x0/0x520 returned 0 after 26 msecs > calling hpet_late_init+0x0/0x1c0 > BUG: unable to handle kernel NULL pointer dereference at 000000000000008c > IP: [<ffffffff80d228be>] hpet_late_init+0xfe/0x1c0 > PGD 0 > Oops: 0000 [1] SMP > CPU 0 > Modules linked in: > Pid: 1, comm: swapper Not tainted 2.6.27-rc5 #29725 > RIP: 0010:[<ffffffff80d228be>] [<ffffffff80d228be>] hpet_late_init+0xfe/0x1c0 > RSP: 0018:ffff88003fa07dd0 EFLAGS: 00010246 > RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 > RDX: ffffc20000000160 RSI: 0000000000000000 RDI: 0000000000000003 > RBP: ffff88003fa07e90 R08: 0000000000000000 R09: ffff88003fa07dd0 > R10: 0000000000000001 R11: 0000000000000000 R12: ffff88003fa07dd0 > R13: 0000000000000002 R14: ffffc20000000000 R15: 000000006f57e511 > FS: 0000000000000000(0000) GS:ffffffff80cf6a80(0000) knlGS:0000000000000000 > CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b > CR2: 000000000000008c CR3: 0000000000201000 CR4: 00000000000006e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > Process swapper (pid: 1, threadinfo ffff88003fa06000, task ffff88003fa08000) > Stack: 00000000fed00000 ffffc20000000000 0000000100000003 0000000800000002 > 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > Call Trace: > [<ffffffff80d227c0>] ? hpet_late_init+0x0/0x1c0 > [<ffffffff80209045>] do_one_initcall+0x45/0x190 > [<ffffffff80296f39>] ? register_irq_proc+0x19/0xe0 > [<ffffffff80d0d140>] ? early_idt_handler+0x0/0x73 > [<ffffffff80d0dabc>] kernel_init+0x14c/0x1b0 > [<ffffffff80942ac1>] ? trace_hardirqs_on_thunk+0x3a/0x3f > [<ffffffff8020dbd9>] child_rip+0xa/0x11 > [<ffffffff8020ceee>] ? restore_args+0x0/0x30 > [<ffffffff80d0d970>] ? kernel_init+0x0/0x1b0 > [<ffffffff8020dbcf>] ? child_rip+0x0/0x11 > Code: 20 48 83 c1 01 48 39 f1 75 e3 44 89 e8 4c 8b 05 29 29 22 00 31 f6 48 8d 78 01 66 66 90 89 f0 48 8d 04 80 48 c1 e0 05 4a 8d 0c 00 <f6> 81 8c 00 00 00 08 74 26 8b 81 80 00 00 00 8b 91 88 00 00 00 > RIP [<ffffffff80d228be>] hpet_late_init+0xfe/0x1c0 > RSP <ffff88003fa07dd0> > CR2: 000000000000008c > Kernel panic - not syncing: Fatal exception There was one code path, with CONFIG_PCI_MSI disabled, where we were accessing hpet_devs without initialization. That resulted in the above crash. The change below adds a check for hpet_devs. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: HPET_MSI Initialise per-cpu HPET timersvenkatesh.pallipadi@intel.com2008-10-161-2/+293
| | | | | | | | | | | | | | | Initialize a per CPU HPET MSI timer when possible. We retain the HPET timer 0 (IRQ 0) and timer 1 (IRQ 8) as is when legacy mode is being used. We setup the remaining HPET timers as per CPU MSI based timers. This per CPU timer will eliminate the need for timer broadcasting with IRQ 0 when there is non-functional LAPIC timer across CPU deep C-states. If there are more CPUs than number of available timers, CPUs that do not find any timer to use will continue using LAPIC and IRQ 0 broadcast. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: HPET_MSI Basic HPET_MSI setup code, cleanupsIngo Molnar2008-10-161-25/+25
| | | | | | small style cleanups. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: HPET_MSI Basic HPET_MSI setup codevenkatesh.pallipadi@intel.com2008-10-161-0/+54
| | | | | | | | | Basic HPET MSI setup code. Routines to perform basic MSI read write in HPET memory map and setting up irq_chip for HPET MSI. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: HPET_MSI Refactor code in preparation for HPET_MSIvenkatesh.pallipadi@intel.com2008-10-161-15/+27
| | | | | | | | | | Preparatory patch before the actual HPET MSI changes. Sets up hpet_set_mode and hpet_next_event for the MSI related changes. Just the code refactoring and should be zero functional change. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge commit 'v2.6.27-rc6' into timers/hpetIngo Molnar2008-09-141-6/+37
|\
| * 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>
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