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2019-06-29x86/timer: Skip PIT initialization on modern chipsetsThomas Gleixner1-1/+24
Recent Intel chipsets including Skylake and ApolloLake have a special ITSSPRC register which allows the 8254 PIT to be gated. When gated, the 8254 registers can still be programmed as normal, but there are no IRQ0 timer interrupts. Some products such as the Connex L1430 and exone go Rugged E11 use this register to ship with the PIT gated by default. This causes Linux to fail to boot: Kernel panic - not syncing: IO-APIC + timer doesn't work! Boot with apic=debug and send a report. The panic happens before the framebuffer is initialized, so to the user, it appears as an early boot hang on a black screen. Affected products typically have a BIOS option that can be used to enable the 8254 and make Linux work (Chipset -> South Cluster Configuration -> Miscellaneous Configuration -> 8254 Clock Gating), however it would be best to make Linux support the no-8254 case. Modern sytems allow to discover the TSC and local APIC timer frequencies, so the calibration against the PIT is not required. These systems have always running timers and the local APIC timer works also in deep power states. So the setup of the PIT including the IO-APIC timer interrupt delivery checks are a pointless exercise. Skip the PIT setup and the IO-APIC timer interrupt checks on these systems, which avoids the panic caused by non ticking PITs and also speeds up the boot process. Thanks to Daniel for providing the changelog, initial analysis of the problem and testing against a variety of machines. Reported-by: Daniel Drake <drake@endlessm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Daniel Drake <drake@endlessm.com> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: linux@endlessm.com Cc: rafael.j.wysocki@intel.com Cc: hdegoede@redhat.com Link: https://lkml.kernel.org/r/20190628072307.24678-1-drake@endlessm.com
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-14x86/kernel: Audit and remove any unnecessary uses of module.hPaul Gortmaker1-1/+1
Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance for the presence of either and replace as needed. Build testing revealed some implicit header usage that was fixed up accordingly. Note that some bool/obj-y instances remain since module.h is the header for some exception table entry stuff, and for things like __init_or_module (code that is tossed when MODULES=n). Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160714001901.31603-4-paul.gortmaker@windriver.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-10clockevents/drivers/i8253: Migrate to new 'set-state' interfaceViresh Kumar1-1/+1
Migrate i8253 driver to the new 'set-state' interface provided by clockevents core, the earlier 'set-mode' interface is marked obsolete now. This also enables us to implement callbacks for new states of clockevent devices, for example: ONESHOT_STOPPED. Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2011-07-01x86: Use common i8253 clockeventThomas Gleixner1-90/+3
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20110609130622.026152527@linutronix.de
2011-06-09x86: i8253: Consolidate definitions of global_clock_eventRalf Baechle1-0/+1
There are multiple declarations of global_clock_event in header files specific to particular clock event implementations. Consolidate them in <asm/time.h> and make sure all users include that header. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Venkatesh Pallipadi (Venki) <venki@google.com> Link: http://lkml.kernel.org/r/20110601180610.762763451@duck.linux-mips.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-06-09i8253: Consolidate all kernel definitions of i8253_lockRalf Baechle1-3/+0
Move them to drivers/clocksource/i8253.c and remove the implementations in arch/ [ tglx: Avoid the extra file in lib - folded arch patches in. The export will become conditional in a later step ] Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Link: http://lkml.kernel.org/r/20110601180610.221426078@duck.linux-mips.net Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-06-09i8253: Create linux/i8253.h and use it in all 8253 related filesRalf Baechle1-1/+1
Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Link: http://lkml.kernel.org/r/20110601180610.054254048@duck.linux-mips.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de> arch/arm/mach-footbridge/isa-timer.c | 2 +- arch/mips/cobalt/time.c | 2 +- arch/mips/jazz/irq.c | 2 +- arch/mips/kernel/i8253.c | 2 +- arch/mips/mti-malta/malta-time.c | 2 +- arch/mips/sgi-ip22/ip22-time.c | 2 +- arch/mips/sni/time.c | 2 +- arch/x86/kernel/apic/apic.c | 2 +- arch/x86/kernel/apm_32.c | 2 +- arch/x86/kernel/hpet.c | 2 +- arch/x86/kernel/i8253.c | 2 +- arch/x86/kernel/time.c | 2 +- drivers/block/hd.c | 2 +- drivers/clocksource/i8253.c | 2 +- drivers/input/gameport/gameport.c | 2 +- drivers/input/joystick/analog.c | 2 +- drivers/input/misc/pcspkr.c | 2 +- include/linux/i8253.h | 11 +++++++++++ sound/drivers/pcsp/pcsp.h | 2 +- 19 files changed, 29 insertions(+), 18 deletions(-)
2011-05-19x86: Convert PIT to clockevents_config_and_register()Thomas Gleixner1-5/+1
Let the core do the work. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Link: http://lkml.kernel.org/r/%3C20110518210136.545615675%40linutronix.de%3E
2011-05-14Merge branch 'consolidate-clksrc-i8253' of ↵Thomas Gleixner1-75/+1
master.kernel.org:~rmk/linux-2.6-arm into timers/clocksource Conflicts: arch/ia64/kernel/cyclone.c arch/mips/kernel/i8253.c arch/x86/kernel/i8253.c Reason: Resolve conflicts so further cleanups do not conflict further Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-14clocksource: convert x86 to generic i8253 clocksourceRussell King1-78/+1
Convert x86 i8253 clocksource code to use generic i8253 clocksource. Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-21x86: Convert remaining x86 clocksources to clocksource_register_hz/khzJohn Stultz1-5/+1
This converts the remaining x86 clocksources to use clocksource_register_hz/khz. CC: jacob.jun.pan@intel.com CC: Glauber Costa <glommer@redhat.com> CC: Dimitri Sivanich <sivanich@sgi.com> CC: Rusty Russell <rusty@rustcorp.com.au> CC: Jeremy Fitzhardinge <jeremy@xensource.com> CC: Chris McDermott <lcm@us.ibm.com> CC: Thomas Gleixner <tglx@linutronix.de> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen] Signed-off-by: John Stultz <johnstul@us.ibm.com>
2010-03-02i8253: Convert i8253_lock to raw_spinlockThomas Gleixner1-7/+7
i8253_lock needs to be a real spinlock in preempt-rt, i.e. it can not be converted to a sleeping lock. Convert it to raw_spinlock and fix up all users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Takashi Iwai <tiwai@suse.de> Cc: Jens Axboe <jens.axboe@oracle.com> LKML-Reference: <20100217163751.030764372@linutronix.de>
2009-08-21x86: Do not unregister PIT clocksource on PIT oneshot setup/shutdownThomas Gleixner1-19/+0
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 Bergmann1-0/+1
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 Damm1-1/+1
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 Rajput1-35/+33
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 Russell1-1/+1
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 Mita1-1/+2
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 Mita1-1/+2
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 Harrison1-1/+1
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 Cox1-15/+15
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 Baechle1-8/+4
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 Gleixner1-0/+19
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 Gleixner1-0/+1
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 Gleixner1-1/+9
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 Arlott1-1/+1
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 Jones1-1/+1
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 Gleixner1-0/+208
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>