summaryrefslogtreecommitdiff
path: root/drivers/clocksource
AgeCommit message (Collapse)Author
2014-11-19clockevent: sun4i: Fix race condition in the probe codeMaxime Ripard
The interrupts were activated and the handler registered before the clockevent was registered in the probe function. The interrupt handler, however, was making the assumption that the clockevent device was registered. That could cause a null pointer dereference if the timer interrupt was firing during this narrow window. Fix that by moving the clockevent registration before the interrupt is enabled. Reported-by: Roman Byshko <rbyshko@gmail.com> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Cc: stable@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-10-26ARM/ARM64: arch-timer: fix arch_timer_probed logicMarc Zyngier
Commit c387f07e6205 (clocksource: arm_arch_timer: Discard unavailable timers correctly) changed the way the driver makes sure both the memory and system-register timers have been probed before finalizing the probing. There is a interesting flaw in this logic that leads to this final step never to be executed. Things seems to work pretty well until something actually needs the data that is produced during this final stage. For example, KVM explodes on the first run of a guest when executed on a platform that has both memory and sysreg nodes (Juno, for example). Just fix the damned logic, and enjoy booting VMs again. Tested on a Juno system. Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Christoffer Dall <christoffer.dall@linaro.org> Reported-by: Riku Voipio <riku.voipio@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-10-15Merge branch 'for-3.18-consistent-ops' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu consistent-ops changes from Tejun Heo: "Way back, before the current percpu allocator was implemented, static and dynamic percpu memory areas were allocated and handled separately and had their own accessors. The distinction has been gone for many years now; however, the now duplicate two sets of accessors remained with the pointer based ones - this_cpu_*() - evolving various other operations over time. During the process, we also accumulated other inconsistent operations. This pull request contains Christoph's patches to clean up the duplicate accessor situation. __get_cpu_var() uses are replaced with with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr(). Unfortunately, the former sometimes is tricky thanks to C being a bit messy with the distinction between lvalues and pointers, which led to a rather ugly solution for cpumask_var_t involving the introduction of this_cpu_cpumask_var_ptr(). This converts most of the uses but not all. Christoph will follow up with the remaining conversions in this merge window and hopefully remove the obsolete accessors" * 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits) irqchip: Properly fetch the per cpu offset percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write. percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t Revert "powerpc: Replace __get_cpu_var uses" percpu: Remove __this_cpu_ptr clocksource: Replace __this_cpu_ptr with raw_cpu_ptr sparc: Replace __get_cpu_var uses avr32: Replace __get_cpu_var with __this_cpu_write blackfin: Replace __get_cpu_var uses tile: Use this_cpu_ptr() for hardware counters tile: Replace __get_cpu_var uses powerpc: Replace __get_cpu_var uses alpha: Replace __get_cpu_var ia64: Replace __get_cpu_var uses s390: cio driver &__get_cpu_var replacements s390: Replace __get_cpu_var uses mips: Replace __get_cpu_var uses MIPS: Replace __get_cpu_var uses in FPU emulator. arm: Replace __this_cpu_ptr with raw_cpu_ptr ...
2014-10-09Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Nothing really exciting this time: - a few fixlets in the NOHZ code - a new ARM SoC timer abomination. One should expect that we have enough of them already, but they insist on inventing new ones. - the usual bunch of ARM SoC timer updates. That feels like herding cats" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: arm_arch_timer: Consolidate arch_timer_evtstrm_enable clocksource: arm_arch_timer: Enable counter access for 32-bit ARM clocksource: arm_arch_timer: Change clocksource name if CP15 unavailable clocksource: sirf: Disable counter before re-setting it clocksource: cadence_ttc: Add support for 32bit mode clocksource: tcb_clksrc: Sanitize IRQ request clocksource: arm_arch_timer: Discard unavailable timers correctly clocksource: vf_pit_timer: Support shutdown mode ARM: meson6: clocksource: Add Meson6 timer support ARM: meson: documentation: Add timer documentation clocksource: sh_tmu: Document r8a7779 binding clocksource: sh_mtu2: Document r7s72100 binding clocksource: sh_cmt: Document SoC specific bindings timerfd: Remove an always true check nohz: Avoid tick's double reprogramming in highres mode nohz: Fix spurious periodic tick behaviour in low-res dynticks mode
2014-10-08Merge tag 'drivers-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC driver updates from Arnd Bergmann: "These are changes for drivers that are intimately tied to some SoC and for some reason could not get merged through the respective subsystem maintainer tree. Most of the new code is for the Keystone Navigator driver, which is new base support that is going to be needed for their hardware accelerated network driver and other units. Most of the commits are for moving old code around from at91 and omap for things that are done in device drivers nowadays. - at91: move reset, poweroff, memory and clocksource code into drivers directories - socfpga: add edac driver (through arm-soc, as requested by Boris) - omap: move omap-intc code to drivers/irqchip - sunxi: added an RTC driver for sun6i - omap: mailbox driver related changes - keystone: support for the "Navigator" component - versatile: new reboot, led and soc drivers" * tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (92 commits) bus: arm-ccn: Fix spurious warning message leds: add device tree bindings for register bit LEDs soc: add driver for the ARM RealView power: reset: driver for the Versatile syscon reboot leds: add a driver for syscon-based LEDs drivers/soc: ti: fix build break with modules MAINTAINERS: Add Keystone Multicore Navigator drivers entry soc: ti: add Keystone Navigator DMA support Documentation: dt: soc: add Keystone Navigator DMA bindings soc: ti: add Keystone Navigator QMSS driver Documentation: dt: soc: add Keystone Navigator QMSS bindings rtc: sunxi: Depend on platforms sun4i/sun7i that actually have the rtc rtc: sun6i: Add sun6i RTC driver irqchip: omap-intc: remove unnecessary comments irqchip: omap-intc: correct maximum number or MIR registers irqchip: omap-intc: enable TURBO idle mode irqchip: omap-intc: enable IP protection irqchip: omap-intc: remove unnecesary of_address_to_resource() call irqchip: omap-intc: comment style cleanup irqchip: omap-intc: minor improvement to omap_irq_pending() ...
2014-09-29clocksource: arm_arch_timer: Consolidate arch_timer_evtstrm_enableNathan Lynch
The arch_timer_evtstrm_enable hooks in arm and arm64 are substantially similar, the only difference being a CONFIG_COMPAT-conditional section which is relevant only for arm64. Copy the arm64 version to the driver, removing the arch-specific hooks. Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com>
2014-09-29clocksource: arm_arch_timer: Enable counter access for 32-bit ARMNathan Lynch
The only difference between arm and arm64's implementations of arch_counter_set_user_access is that 32-bit ARM does not enable user access to the virtual counter. We want to enable this access for the 32-bit ARM VDSO, so copy the arm64 version to the driver itself, and remove the arch-specific implementations. Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com>
2014-09-29clocksource: arm_arch_timer: Change clocksource name if CP15 unavailableNathan Lynch
The arm and arm64 VDSOs need CP15 access to the architected counter. If this is unavailable (which is allowed by ARM v7), indicate this by changing the clocksource name to "arch_mem_counter" before registering the clocksource. Suggested by Stephen Boyd. Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com>
2014-09-29clocksource: sirf: Disable counter before re-setting itHao Liu
According to HW spec, we have to disable the counter before setting it, if we don't this, in pressure test, sometimes the timer might not generate interrupt any more. And this patch also fixes a typo for register set by changing 0x7 to 0x3. 0x7 is loop mode in HW, but here we are using oneshot 0x3. Signed-off-by: Hao Liu <Hao.Liu@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-09-29clocksource: cadence_ttc: Add support for 32bit modeMichal Simek
New TTCs support 32bit mode. Older versions support only 16bit modes. Keep 16bit mode as default and 32bit optional. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-09-29clocksource: tcb_clksrc: Sanitize IRQ requestGael Portay
The clock is not unprepared in case of the request IRQ fails. Also update to request_irq. Signed-off-by: Gaël PORTAY <gael.portay@gmail.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-09-29clocksource: arm_arch_timer: Discard unavailable timers correctlySudeep Holla
Currently we wait until both cp15 and mem timers are probed if we have both timer device nodes present in the device tree without checking if the device is actually available. If one of the timer device node present is disabled, the system locks up on the boot as no timer gets registered. This patch adds the check for the availability of the timer device so that unavailable timers are discarded correctly. It also adds the missing of_node_put. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-09-29clocksource: vf_pit_timer: Support shutdown modeStefan Agner
In order to avoid waking up the system in a low power mode, the clocksource should not generate interrupts anymore. Disable the PIT timer interrupt when changing into the CLOCK_EVT_MODE_SHUTDOWN mode. [dlezcano] : remove superfluous empty line Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Bill Pringlemeir <bpringlemeir@nbsps.com>
2014-09-29ARM: meson6: clocksource: Add Meson6 timer supportCarlo Caione
Meson6 SoCs are equipped with 5 32-bit timers, called TIMER_A, TIMER_B, TIMER_C, TIMER_D and TIMER_E. The driver is providing clocksource support for the 32-bit counter using TIMER_E. Clockevents are also supported using TIMER_A. Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Carlo Caione <carlo@caione.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
2014-09-15ARM: at91: PIT: Move the driver to drivers/clocksourceMaxime Ripard
Now that we don't depend on anyting in the mach-at91 directory, we can just move the driver to where it belongs. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Boris BREZILLON <boris.brezillon@free-electrons.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Conflicts: arch/arm/mach-at91/Kconfig arch/arm/mach-at91/Makefile
2014-09-08clocksource: tcb_clksrc: sanitize IRQ requestGaël PORTAY
The clock is not unprepared in case of the request IRQ fails. Also update to request_irq. Signed-off-by: Gaël PORTAY <gael.portay@gmail.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-09-08ARM: at91/tclib: move initialization from alloc to probeGaël PORTAY
Move resource retrieval from atmel_tc_alloc to tc_probe to avoid lately reporting resource related issues when a TC block user request a TC block. Moreover, resources retrieval are usually done in the probe function, thus moving them add some consistency with other drivers. Initialization is done once, ie not every time a tc block is requested. If it fails, the device is not appended to the list of tc blocks. Furhermore, the device id is retrieved at probe as well, avoiding parsing DT every time the user requests of tc block. Signed-off-by: Gaël PORTAY <gael.portay@gmail.com> Acked-by: Thierry Reding <thierry.reding@gmail.com> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-08-26clocksource: Replace __this_cpu_ptr with raw_cpu_ptrChristoph Lameter
One newly introduced __this_cpu_ptr should be raw_cpu_ptr. Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26drivers/clocksource: Replace __get_cpu_var used for address calculationChristoph Lameter
Replace __get_cpu_var used for address calculation with this_cpu_ptr. Acked-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26time: Replace __get_cpu_var usesChristoph Lameter
Convert uses of __get_cpu_var for creating a address from a percpu offset to this_cpu_ptr. The two cases where get_cpu_var is used to actually access a percpu variable are changed to use this_cpu_read/raw_cpu_read. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-08Merge tag 'soc-for-3.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC platform changes from Olof Johansson: "This is the bulk of new SoC enablement and other platform changes for 3.17: - Samsung S5PV210 has been converted to DT and multiplatform - Clock drivers and bindings for some of the lower-end i.MX 1/2 platforms - Kirkwood, one of the popular Marvell platforms, is folded into the mvebu platform code, removing mach-kirkwood - Hwmod data for TI AM43xx and DRA7 platforms - More additions of Renesas shmobile platform support - Removal of plat-samsung contents that can be removed with S5PV210 being multiplatform/DT-enabled and the other two old platforms being removed New platforms (most with only basic support right now): - Hisilicon X5HD2 settop box chipset is introduced - Mediatek MT6589 (mobile chipset) is introduced - Broadcom BCM7xxx settop box chipset is introduced + as usual a lot other pieces all over the platform code" * tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits) ARM: hisi: remove smp from machine descriptor power: reset: move hisilicon reboot code ARM: dts: Add hix5hd2-dkb dts file. ARM: debug: Rename Hi3716 to HIX5HD2 ARM: hisi: enable hix5hd2 SoC ARM: hisi: add ARCH_HISI MAINTAINERS: add entry for Broadcom ARM STB architecture ARM: brcmstb: select GISB arbiter and interrupt drivers ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs ARM: configs: enable SMP in bcm_defconfig ARM: add SMP support for Broadcom mobile SoCs Documentation: arm: misc updates to Marvell EBU SoC status Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC ARM: mvebu: fix build without platforms selected ARM: mvebu: add cpuidle support for Armada 38x ARM: mvebu: add cpuidle support for Armada 370 cpuidle: mvebu: add Armada 38x support cpuidle: mvebu: add Armada 370 support cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7 ARM: mvebu: export the SCU address ...
2014-08-05Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer and time updates from Thomas Gleixner: "A rather large update of timers, timekeeping & co - Core timekeeping code is year-2038 safe now for 32bit machines. Now we just need to fix all in kernel users and the gazillion of user space interfaces which rely on timespec/timeval :) - Better cache layout for the timekeeping internal data structures. - Proper nanosecond based interfaces for in kernel users. - Tree wide cleanup of code which wants nanoseconds but does hoops and loops to convert back and forth from timespecs. Some of it definitely belongs into the ugly code museum. - Consolidation of the timekeeping interface zoo. - A fast NMI safe accessor to clock monotonic for tracing. This is a long standing request to support correlated user/kernel space traces. With proper NTP frequency correction it's also suitable for correlation of traces accross separate machines. - Checkpoint/restart support for timerfd. - A few NOHZ[_FULL] improvements in the [hr]timer code. - Code move from kernel to kernel/time of all time* related code. - New clocksource/event drivers from the ARM universe. I'm really impressed that despite an architected timer in the newer chips SoC manufacturers insist on inventing new and differently broken SoC specific timers. [ Ed. "Impressed"? I don't think that word means what you think it means ] - Another round of code move from arch to drivers. Looks like most of the legacy mess in ARM regarding timers is sorted out except for a few obnoxious strongholds. - The usual updates and fixlets all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits) timekeeping: Fixup typo in update_vsyscall_old definition clocksource: document some basic timekeeping concepts timekeeping: Use cached ntp_tick_length when accumulating error timekeeping: Rework frequency adjustments to work better w/ nohz timekeeping: Minor fixup for timespec64->timespec assignment ftrace: Provide trace clocks monotonic timekeeping: Provide fast and NMI safe access to CLOCK_MONOTONIC seqcount: Add raw_write_seqcount_latch() seqcount: Provide raw_read_seqcount() timekeeping: Use tk_read_base as argument for timekeeping_get_ns() timekeeping: Create struct tk_read_base and use it in struct timekeeper timekeeping: Restructure the timekeeper some more clocksource: Get rid of cycle_last clocksource: Move cycle_last validation to core code clocksource: Make delta calculation a function wireless: ath9k: Get rid of timespec conversions drm: vmwgfx: Use nsec based interfaces drm: i915: Use nsec based interfaces timekeeping: Provide ktime_get_raw() hangcheck-timer: Use ktime_get_ns() ...
2014-08-05Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: "Included in this update: - perf updates from Will Deacon: The main changes are callchain stability fixes from Jean Pihet and event mapping and PMU name rework from Mark Rutland The latter is preparatory work for enabling some code re-use with arm64 in the future. - updates for nommu from Uwe Kleine-König: Two different fixes for the same problem making some ARM nommu configurations not boot since 3.6-rc1. The problem is that user_addr_max returned the biggest available RAM address which makes some copy_from_user variants fail to read from XIP memory. - deprecate legacy OMAP DMA API, in preparation for it's removal. The popular drivers have been converted over, leaving a very small number of rarely used drivers, which hopefully can be converted during the next cycle with a bit more visibility (and hopefully people popping out of the woodwork to help test) - more tweaks for BE systems, particularly with the kernel image format. In connection with this, I've cleaned up the way we generate the linker script for the decompressor. - removal of hard-coded assumptions of the kernel stack size, making everywhere depend on the value of THREAD_SIZE_ORDER. - MCPM updates from Nicolas Pitre. - Make it easier for proper CPU part number checks (which should always include the vendor field). - Assembly code optimisation - use the "bx" instruction when returning from a function on ARMv6+ rather than "mov pc, reg". - Save the last kernel misaligned fault location and report it via the procfs alignment file. - Clean up the way we create the initial stack frame, which is a repeated pattern in several different locations. - Support for 8-byte get_user(), needed for some DRM implementations. - mcs locking from Will Deacon. - Save and restore a few more Cortex-A9 registers (for errata workarounds) - Fix various aspects of the SWP emulation, and the ELF hwcap for the SWP instruction. - Update LPAE logic for pte_write and pmd_write to make it more correct. - Support for Broadcom Brahma15 CPU cores. - ARM assembly crypto updates from Ard Biesheuvel" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (53 commits) ARM: add comments to the early page table remap code ARM: 8122/1: smp_scu: enable SCU standby support ARM: 8121/1: smp_scu: use macro for SCU enable bit ARM: 8120/1: crypto: sha512: add ARM NEON implementation ARM: 8119/1: crypto: sha1: add ARM NEON implementation ARM: 8118/1: crypto: sha1/make use of common SHA-1 structures ARM: 8113/1: remove remaining definitions of PLAT_PHYS_OFFSET from <mach/memory.h> ARM: 8111/1: Enable erratum 798181 for Broadcom Brahma-B15 ARM: 8110/1: do CPU-specific init for Broadcom Brahma15 cores ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear ARM: hwcap: disable HWCAP_SWP if the CPU advertises it has exclusives ARM: SWP emulation: only initialise on ARMv7 CPUs ARM: SWP emulation: always enable when SMP is enabled ARM: 8103/1: save/restore Cortex-A9 CP15 registers on suspend/resume ARM: 8098/1: mcs lock: implement wfe-based polling for MCS locking ARM: 8091/2: add get_user() support for 8 byte types ARM: 8097/1: unistd.h: relocate comments back to place ARM: 8096/1: Describe required sort order for textofs-y (TEXT_OFFSET) ARM: 8090/1: add revision info for PL310 errata 588369 and 727915 ...
2014-07-23clocksource: exynos_mct: Only use 32-bits where possibleDoug Anderson
The MCT has a nice 64-bit counter. That means that we _can_ register as a 64-bit clocksource and sched_clock. ...but that doesn't mean we should. The 64-bit counter is read by reading two 32-bit registers. That means reading needs to be something like: - Read upper half - Read lower half - Read upper half and confirm that it hasn't changed. That wouldn't be terrible, but: - THe MCT isn't very fast to access (hundreds of nanoseconds). - The clocksource is queried _all the time_. In total system profiles of real workloads on ChromeOS, we've seen exynos_frc_read() taking 2% or more of CPU time even after optimizing the 3 reads above to 2 (see below). The MCT is clocked at ~24MHz on all known systems. That means that the 32-bit half of the counter rolls over every ~178 seconds. This inspired an optimization in ChromeOS to cache the upper half between calls, moving 3 reads to 2. ...but we can do better! Having a 32-bit timer that flips every 178 seconds is more than sufficient for Linux. Let's just use the lower half of the MCT. Times on 5420 to do 1000000 gettimeofday() calls from userspace: * Original code: 1323852 us * ChromeOS cache upper half: 1173084 us * ChromeOS + ldmia to optimize: 1045674 us * Use lower 32-bit only (this code): 1014429 us As you can see, the time used doesn't increase linearly with the number of reads and we can make 64-bit work almost as fast as 32-bit with a bit of assembly code. But since there's no real gain for 64-bit, let's go with the simplest and fastest implementation. Note: with this change roughly half the time for gettimeofday() is spent in exynos_frc_read(). The rest is timer / system call overhead. Also note: this patch disables the use of the MCT on ARM64 systems until we've sorted out how to make "cycles_t" always 32-bit. Really ARM64 systems should be using arch timers anyway. Signed-off-by: Doug Anderson <dianders@chromium.org> Acked-by Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: exynos_mct: Use readl_relaxed/writel_relaxedDoug Anderson
Using the __raw functions is discouraged. Update the file to consistently use the proper functions. Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: pxa: Add device-tree support for PXA timerRobert Jarzmik
Add device-tree support to PXA platforms. The driver still needs to maintain backward non device-tree compatibility as well, which implies : - a non device-tree init function - a static registers base address in the driver Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: pxa: Move PXA timer to clocksource frameworkRobert Jarzmik
Move time.c from arch/arm/mach-pxa/time.c to drivers/clocksource/pxa_timer.c. Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: clps711x: Add CLPS711X clocksource driverAlexander Shiyan
This adds the clocksource driver for Cirrus Logic CLPS711X series SoCs. Designed primarily for migration CLPS711X subarch for multiplatform & DT, for this as the "OF" and "non-OF" calls implemented. Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: sirf: Fix incorrect clock enable counter for timerZhiwu Song
In the clocksource driver, we didn't explicitly enable the clock. it makes the clk reference counter wrong. We didn't encounter any hang issue because the tick's clock input has been open and is shared by some other hardware components, but if we don't enable those components in kernel, in the stage of disabling unused clk in kernel boot, Linux tick hangs. This patch fixes it. it does an explicit prepare and enable to the clock input, and increases the usage counter of the clk. Signed-off-by: Zhiwu Song <Zhiwu.Song@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: Kconfig: Let EM_TIMER_STI depend on HAS_IOMEMChen Gang
In 'em_sti.c', it will call devm_ioremap_resource() which need HAS_IOMEM. So need let EM_TIMER_STI depend on HAS_IOMEM, too. The related error (with allmodconfig under score): LD init/built-in.o em_sti.c:(.text.em_sti_probe+0x84): undefined reference to `devm_ioremap_resource' make: *** [vmlinux] Error 1 Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: Add support for the Mediatek SoCsMatthias Brugger
This patch adds a clock source and clock event for the timer found on the Mediatek SoCs. The Mediatek General Purpose Timer block provides five 32 bit timers and one 64 bit timer. Two 32 bit timers are used by this driver: TIMER1: clock events supporting periodic and oneshot events TIMER2: clock source configured as a free running counter The General Purpose Timer block can be run with two clocks. A 13 MHz system clock and the RTC clock running at 32 KHz. This implementation uses the system clock with no clock source divider. The interrupts are shared between the different timers and have to be read back from a register. We just enable one interrupt for the clock event. The clock event timer is used by all cores. Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23clocksource: sh_mtu2: Tidy up Kconfig typo for MTU2Kuninori Morimoto
It should be "MTU2" instead of "TMU2" Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Acked-by: Wolfram Sang <wsa@sang-engineering.com> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-07-23Merge branch 'clockevents/renesas-timers-dt' into clockevents/3.17Daniel Lezcano
2014-07-19Merge tag 'exynos-cpuidle' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into next/soc Merge "Samsung exynos cpuidle update for v3.17" from Kukjin Kim: - add callbacks exynos_suspend() and exynos_powered_up() for support cpuidle through mcpm - skip exynos_cpuidle for exynos5420 because is uses cpuidle-big-liggle generic cpuidle driver - add generic functions to calculate cpu number is used for pmu and this is required for exynos5420 multi-cluster - add of_device_id structure for big.LITTLE cpuidle and add "samsung,exynos5420" compatible string for exynos5420 * tag 'exynos-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung: ARM: EXYNOS: populate suspend and powered_up callbacks for mcpm ARM: EXYNOS: do not allow cpuidle registration for exynos5420 cpuidle: big.LITTLE: init driver for exynos5420 cpuidle: big.LITTLE: Add ARCH_EXYNOS entry in config ARM: EXYNOS: add generic function to calculate cpu number cpuidle: big.LITTLE: add of_device_id structure + Linux 3.16-rc5 Signed-off-by: Olof Johansson <olof@lixom.net>
2014-07-18ARM: make it easier to check the CPU part number correctlyRussell King
Ensure that platform maintainers check the CPU part number in the right manner: the CPU part number is meaningless without also checking the CPU implement(e|o)r (choose your preferred spelling!) Provide an interface which returns both the implementer and part number together, and update the definitions to include the implementer. Mark the old function as being deprecated... indeed, using the old function with the definitions will now always evaluate as false, so people must update their un-merged code to the new function. While this could be avoided by adding new definitions, we'd also have to create new names for them which would be awkward. Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-16Merge tag 'v3.16-rc5' into timers/coreThomas Gleixner
Reason: Bring in upstream modifications, so the pending changes which depend on them can be queued.
2014-07-06Merge tag 'tegra-for-3.17-delay-timer' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into next/soc Merge "ARM: tegra: use us counter as delay timer" from Stephen Warren: Tegra has a micro-second counter whose rate doesn't vary with cpufreq changes. Register it so it can be used as the delay timer, so delays aren't influenced by cpufreq. * tag 'tegra-for-3.17-delay-timer' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux: clocksource: tegra: Use us counter as delay timer ARM: choose highest resolution delay timer kernel: add calibration_delay_done() Signed-off-by: Olof Johansson <olof@lixom.net>
2014-07-05clocksource: exynos_mct: Register the timer for stable udelayAmit Daniel Kachhap
This patch registers the exynos mct clocksource as the current timer as it has constant clock rate. This will generate correct udelay for the exynos platform and avoid using unnecessary calibrated jiffies. This change has been tested on exynos5420 based board and udelay is very close to expected. Without this patch udelay() on exynos5400 / exynos5800 is wildly inaccurate due to big.LITTLE not adjusting loops_per_jiffy correctly. Also without this patch udelay() on exynos5250 can be innacruate during transitions between frequencies < 800 MHz (you'll go 200 MHz -> 800 MHz -> 300 MHz and will run at 800 MHz for a time with the wrong loops_per_jiffy). [dianders: reworked and created version 3] Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com> Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2014-07-05clocksource: exynos_mct: Fix ftraceDoug Anderson
In (93bfb76 clocksource: exynos_mct: register sched_clock callback) we supported using the MCT as a scheduler clock. We properly marked exynos4_read_sched_clock() as notrace. However, we then went and called another function that _wasn't_ notrace. That means if you do: cd /sys/kernel/debug/tracing/ echo function_graph > current_tracer You'll get a crash. Fix this (but still let other readers of the MCT be trace-enabled) by adding an extra function. It's important to keep other users of MCT traceable because the MCT is actually quite slow to access and we want exynos4_frc_read() to show up in ftrace profiles if it's the bottleneck. Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2014-07-04clocksource: sh_mtu2: Add DT supportLaurent Pinchart
Document DT bindings and parse them in the MTU2 driver. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Wolfram Sang <wsa@sang-engineering.com>
2014-07-04clocksource: sh_tmu: Add DT supportLaurent Pinchart
Document DT bindings and parse them in the TMU driver. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Simon Horman <horms+renesas@verge.net.au>
2014-07-04clocksource: sh_cmt: Add DT supportLaurent Pinchart
Document DT bindings and parse them in the CMT driver. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Simon Horman <horms+renesas@verge.net.au>
2014-07-02clocksource: sh_mtu2: Replace global spinlock with a per-device spinlockLaurent Pinchart
The global spinlock is used to protect the shared start/stop register. Now that all MTU2 channels are handled by a single device instance, use a per-device spinlock. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Wolfram Sang <wsa@sang-engineering.com>
2014-07-02clocksource: sh_mtu2: Drop support for legacy platform dataLaurent Pinchart
Now that all platforms have switched to the new-style platform data, drop support for the legacy version. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Wolfram Sang <wsa@sang-engineering.com>
2014-07-02clocksource: sh_tmu: Replace global spinlock with a per-device spinlockLaurent Pinchart
The global spinlock is used to protect the shared start/stop register. Now that all TMU channels are handled by a single device instance, use a per-device spinlock. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Simon Horman <horms+renesas@verge.net.au>
2014-07-02clocksource: sh_tmu: Drop support for legacy platform dataLaurent Pinchart
Now that all platforms have switched to the new-style platform data, drop support for the legacy version. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Simon Horman <horms+renesas@verge.net.au>
2014-07-02clocksource: sh_cmt: Replace global spinlock with a per-device spinlockLaurent Pinchart
The global spinlock is used to protect the shared start/stop register. Now that all CMT channels are handled by a single device instance, use a per-device spinlock. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Simon Horman <horms+renesas@verge.net.au>
2014-07-02clocksource: sh_cmt: Drop support for legacy platform dataLaurent Pinchart
Now that all platforms have switched to the new-style platform data, drop support for the legacy version. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Simon Horman <horms+renesas@verge.net.au>
2014-06-21clocksource: Add a Kconfig menuJean Delvare
Move the clocksource Kconfig entries into their own menu, so that they don't pollute the main device driver menu. Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Link: http://lkml.kernel.org/r/20140616114845.343e9960@endymion.delvare Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-06-16clocksource: tegra: Use us counter as delay timerPeter De Schrijver
All Tegra SoCs have a freerunning microsecond counter which can be used as a delay timer. Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Stephen Warren <swarren@nvidia.com>