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2021-06-16arm: zynq: don't disable CONFIG_ARM_GLOBAL_TIMER due to CONFIG_CPU_FREQ anymoreAndrea Merello
Now ARM global timer driver could work even if it's source clock rate changes, so we don't need to disable that driver when cpu frequency scaling is in use. This cause Zynq arch to get support for timer delay and get_cycles(). Signed-off-by: Andrea Merello <andrea.merello@gmail.com> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: Michal Simek <michal.simek@xilinx.com> Cc: Sören Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210406130045.15491-3-andrea.merello@gmail.com
2021-06-16clocksource/drivers/arm_global_timer: Implement rate compensation whenever ↵Andrea Merello
source clock changes This patch adds rate change notification support for the parent clock; should that clock change, then we try to adjust the our prescaler in order to compensate (i.e. we adjust to still get the same timer frequency). This is loosely based on what it's done in timer-cadence-ttc. timer-sun51, mips-gic-timer and smp_twd.c also seem to look at their parent clock rate and to perform some kind of adjustment whenever needed. In this particular case we have only one single counter and prescaler for all clocksource, clockevent and timer_delay, and we just update it for all (i.e. we don't let it go and call clockevents_update_freq() to notify to the kernel that our rate has changed). Note that, there is apparently no other way to fixup things, because once we call register_current_timer_delay(), specifying the timer rate, it seems that that rate is not supposed to change ever. In order for this mechanism to work, we have to make assumptions about how much the initial clock is supposed to eventually decrease from the initial one, and set our initial prescaler to a value that we can eventually decrease enough to compensate. We provide an option in KConfig for this. In case we end up in a situation in which we are not able to compensate the parent clock change, we fail returning NOTIFY_BAD. This fixes a real-world problem with Zynq arch not being able to use this driver and CPU_FREQ at the same time (because ARM global timer is fed by the CPU clock, which may keep changing when CPU_FREQ is enabled). Signed-off-by: Andrea Merello <andrea.merello@gmail.com> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: Michal Simek <michal.simek@xilinx.com> Cc: Sören Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210406130045.15491-2-andrea.merello@gmail.com
2021-02-22Merge tag 'timers-urgent-2021-02-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "A small set of clockevent fixes which fell through the cracks before the 5.11 release: - Ensure a clock is enabled on sh_cmt - Trivial compile fail and compile warning fixes" * tag 'timers-urgent-2021-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/drivers/mxs_timer: Add missing semicolon when DEBUG is defined clocksource/drivers/sh_cmt: Make sure channel clock supply is enabled clocksource/drivers/ixp4xx: Select TIMER_OF when needed
2021-02-10Merge tag 'timers-v5.12-rc1' of ↵Thomas Gleixner
https://git.linaro.org/people/daniel.lezcano/linux into timers/core Pull clocksource/events updates from Daniel Lezcano: - Drop dead code on efm32 (Uwe Kleine-König) - Move pr_fmt() before the includes on davinci driver (Bartosz Golaszewski) - Clarified timer interrupt must be specified on nuvoton DT bindings (Jonathan Neuschäfer) - Remove tango, sirf, u300 and atlas timer drivers (Arnd Bergman) - Add suspend/resume on pit64b (Claudiu Beznea) Link: https://lore.kernel.org/r/3747fbde-134f-5e1d-47d5-8776c1a52aa1@linaro.org
2021-02-03clocksource/drivers/prima: Remove sirf prima driverArnd Bergmann
The CSR SiRF prima2/atlas platforms are getting removed, so this driver is no longer needed. Cc: Barry Song <baohua@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Barry Song <baohua@kernel.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210120131559.1971359-5-arnd@kernel.org
2021-02-03clocksource/drivers/atlas: Remove sirf atlas driverArnd Bergmann
The CSR SiRF prima2/atlas platforms are getting removed, so this driver is no longer needed. Cc: Barry Song <baohua@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Barry Song <baohua@kernel.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210120131559.1971359-4-arnd@kernel.org
2021-02-03clocksource/drivers/tango: Remove tango driverArnd Bergmann
The tango platform is getting removed, so the driver is no longer needed. Cc: Marc Gonzalez <marc.w.gonzalez@free.fr> Cc: Mans Rullgard <mans@mansr.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Mans Rullgard <mans@mansr.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210120131559.1971359-3-arnd@kernel.org
2021-02-03clocksource/drivers/u300: Remove the u300 driverArnd Bergmann
The ST-Ericsson U300 platform is getting removed, so this driver is no longer needed. Cc: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210120131559.1971359-2-arnd@kernel.org
2021-01-18clocksource/drivers/efm32: Drop unused timer codeUwe Kleine-König
Support for this machine was just removed, so drop the now unused timer code, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210115155130.185010-4-u.kleine-koenig@pengutronix.de
2021-01-18clocksource/drivers/ixp4xx: Select TIMER_OF when neededArnd Bergmann
Compile-testing the ixp4xx timer with CONFIG_OF enabled but CONFIG_TIMER_OF disabled leads to a harmless warning: arm-linux-gnueabi-ld: warning: orphan section `__timer_of_table' from `drivers/clocksource/timer-ixp4xx.o' being placed in section `__timer_of_table' Move the select statement from the platform code into the driver so it always gets enabled in configurations that rely on it. Fixes: 40df14cc5cc0 ("clocksource/drivers/ixp4xx: Add OF initialization support") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20210103135955.3808976-1-arnd@kernel.org
2020-12-16Merge tag 'asm-generic-timers-5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic cross-architecture timer cleanup from Arnd Bergmann: "This cleans up two ancient timer features that were never completed in the past, CONFIG_GENERIC_CLOCKEVENTS and CONFIG_ARCH_USES_GETTIMEOFFSET. There was only one user left for the ARCH_USES_GETTIMEOFFSET variant of clocksource implementations, the ARM EBSA110 platform. Rather than changing to use modern timekeeping, we remove the platform entirely as Russell no longer uses his machine and nobody else seems to have one any more. The conditional code for using arch_gettimeoffset() is removed as a result. For CONFIG_GENERIC_CLOCKEVENTS, there are still a couple of platforms not using clockevent drivers: parisc, ia64, most of m68k, and one Arm platform. These all do timer ticks slighly differently, and this gets cleaned up to the point they at least all call the same helper function. Instead of most platforms using 'select GENERIC_CLOCKEVENTS' in Kconfig, the polarity is now reversed, with the few remaining ones selecting LEGACY_TIMER_TICK instead" * tag 'asm-generic-timers-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: timekeeping: default GENERIC_CLOCKEVENTS to enabled timekeeping: remove xtime_update m68k: remove timer_interrupt() function m68k: change remaining timers to legacy_timer_tick m68k: m68328: use legacy_timer_tick() m68k: sun3/sun3c: use legacy_timer_tick m68k: split heartbeat out of timer function m68k: coldfire: use legacy_timer_tick() parisc: use legacy_timer_tick ARM: rpc: use legacy_timer_tick ia64: convert to legacy_timer_tick timekeeping: add CONFIG_LEGACY_TIMER_TICK timekeeping: remove arch_gettimeoffset net: remove am79c961a driver ARM: remove ebsa110 platform
2020-12-03clocksource/drivers/riscv: Make RISCV_TIMER depends on RISCV_SBIKefeng Wang
The riscv timer is set via SBI timer call, let's make RISCV_TIMER depends on RISCV_SBI, and it also fixes some build issue. Fixes: d5be89a8d118 ("RISC-V: Resurrect the MMIO timer implementation for M-mode systems") Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20201028131230.72907-1-wangkefeng.wang@huawei.com
2020-12-03clocksource/drivers/nps: Remove EZChip NPS clocksource driverVineet Gupta
NPS platform has been removed from ARC port and there are no in-tree users of it now. So RIP ! Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20201105212210.1891598-2-vgupta@synopsys.com
2020-10-30timekeeping: remove arch_gettimeoffsetArnd Bergmann
With Arm EBSA110 gone, nothing uses it any more, so the corresponding code and the Kconfig option can be removed. Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-08-20RISC-V: Remove CLINT related code from timer and archAnup Patel
Right now the RISC-V timer driver is convoluted to support: 1. Linux RISC-V S-mode (with MMU) where it will use TIME CSR for clocksource and SBI timer calls for clockevent device. 2. Linux RISC-V M-mode (without MMU) where it will use CLINT MMIO counter register for clocksource and CLINT MMIO compare register for clockevent device. We now have a separate CLINT timer driver which also provide CLINT based IPI operations so let's remove CLINT MMIO related code from arch/riscv directory and RISC-V timer driver. Signed-off-by: Anup Patel <anup.patel@wdc.com> Tested-by: Emil Renner Berhing <kernel@esmil.dk> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-08-20clocksource/drivers: Add CLINT timer driverAnup Patel
We add a separate CLINT timer driver for Linux RISC-V M-mode (i.e. RISC-V NoMMU kernel). The CLINT MMIO device provides three things: 1. 64bit free running counter register 2. 64bit per-CPU time compare registers 3. 32bit per-CPU inter-processor interrupt registers Unlike other timer devices, CLINT provides IPI registers along with timer registers. To use CLINT IPI registers, the CLINT timer driver provides IPI related callbacks to arch/riscv. Signed-off-by: Anup Patel <anup.patel@wdc.com> Tested-by: Emil Renner Berhing <kernel@esmil.dk> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-08-15Merge tag 'mfd-next-5.9-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd Pull MFD updates from Lee Jones: "Core Frameworks - Make better attempt at matching device with the correct OF node - Allow batch removal of hierarchical sub-devices New Drivers - Add STM32 Clocksource driver - Add support for Khadas System Control Microcontroller Driver Removal - Remove unused driver for TI's SMSC ECE1099 New Device Support - Add support for Intel Emmitsburg PCH to Intel LPSS PCI - Add support for Intel Tiger Lake PCH-H to Intel LPSS PCI - Add support for Dialog DA revision to Dialog DA9063 New Functionality - Add support for AXP803 to be probed by I2C Fix-ups - Numerous W=1 warning fixes - Device Tree changes (stm32-lptimer, gateworks-gsc, khadas,mcu, stmfx, cros-ec, j721e-system-controller) - Enabled Regmap 'fast I/O' in stm32-lptimer - Change BUG_ON to WARN_ON in arizona-core - Remove superfluous code/initialisation (madera, max14577) - Trivial formatting/spelling issues (madera-core, madera-i2c, da9055, max77693-private) - Switch to of_platform_populate() in sprd-sc27xx-spi - Expand out set/get brightness/pwm macros in lm3533-ctrlbank - Disable IRQs on suspend in motorola-cpcap - Clean-up error handling in intel_soc_pmic_mrfld - Ensure correct removal order of sub-devices in madera - Many s/HTTP/HTTPS/ link changes - Ensure name used with Regmap is unique in syscon Bug Fixes - Properly 'put' clock on unbind and error in arizona-core - Fix revision handling in da9063 - Fix 'assignment of read-only location' error in kempld-core - Avoid using the Regmap API when atomic in rn5t618 - Redefine volatile register description in rn5t618 - Use locking to protect event handler in dln2" * tag 'mfd-next-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (76 commits) mfd: syscon: Use a unique name with regmap_config mfd: Replace HTTP links with HTTPS ones mfd: dln2: Run event handler loop under spinlock mfd: madera: Improve handling of regulator unbinding mfd: mfd-core: Add mechanism for removal of a subset of children mfd: intel_soc_pmic_mrfld: Simplify the return expression of intel_scu_ipc_dev_iowrite8() mfd: max14577: Remove redundant initialization of variable current_bits mfd: rn5t618: Fix caching of battery related registers mfd: max77693-private: Drop a duplicated word mfd: da9055: pdata.h: Drop a duplicated word mfd: rn5t618: Make restart handler atomic safe mfd: kempld-core: Fix 'assignment of read-only location' error mfd: axp20x: Allow the AXP803 to be probed by I2C mfd: da9063: Add support for latest DA silicon revision mfd: da9063: Fix revision handling to correctly select reg tables dt-bindings: mfd: st,stmfx: Remove I2C unit name dt-bindings: mfd: ti,j721e-system-controller.yaml: Add J721e system controller mfd: motorola-cpcap: Disable interrupt for suspend mfd: smsc-ece1099: Remove driver mfd: core: Add OF_MFD_CELL_REG() helper ...
2020-07-23clocksource/drivers/ingenic: Add support for the Ingenic X1000 OST.周琰杰 (Zhou Yanjie)
X1000 and SoCs after X1000 (such as X1500 and X1830) had a separate OST, it no longer belongs to TCU. This driver will register both a clocksource and a sched_clock to the system. Tested-by: 周正 (Zhou Zheng) <sernia.zhou@foxmail.com> Co-developed-by: 漆鹏振 (Qi Pengzhen) <aric.pzqi@ingenic.com> Signed-off-by: 漆鹏振 (Qi Pengzhen) <aric.pzqi@ingenic.com> Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com> Reviewed-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20200722171804.97559-3-zhouyanjie@wanyeetech.com
2020-07-23clocksource/drivers/imx: Add support for i.MX TPM driver with ARM64Anson Huang
Allows building and compile-testing the i.MX TPM driver for ARM64. Signed-off-by: Anson Huang <Anson.Huang@nxp.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/1594178168-13007-1-git-send-email-Anson.Huang@nxp.com
2020-06-18clocksource: Add Low Power STM32 timers driverBenjamin Gaignard
Implement clock event driver using low power STM32 timers. Low power timer counters running even when CPUs are stopped. It could be used as clock event broadcaster to wake up CPUs but not like a clocksource because each it rise an interrupt the counter restart from 0. Low power timers have a 16 bits counter and a prescaler which allow to divide the clock per power of 2 to up 128 to target a 32KHz rate. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Signed-off-by: Pascal Paillet <p.paillet@st.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-05-23clocksource: mips-gic-timer: Mark GIC timer as unstable if ref clock changesSerge Semin
Currently clocksource framework doesn't support the clocks with variable frequency. Since MIPS GIC timer ticks rate might be unstable on some platforms, we must make sure that it justifies the clocksource requirements. MIPS GIC timer is incremented with the CPU cluster reference clocks rate. So in case if CPU frequency changes, the MIPS GIC tick rate changes synchronously. Due to this the clocksource subsystem can't rely on the timer to measure system clocks anymore. This commit marks the MIPS GIC based clocksource as unstable if reference clock (normally it's a CPU reference clocks) rate changes. The clocksource will execute a watchdog thread, which lowers the MIPS GIC timer rating to zero and fallbacks to a new stable one. Note we don't need to set the CLOCK_SOURCE_MUST_VERIFY flag to the MIPS GIC clocksource since normally the timer is stable. The only reason why it gets unstable is due to the ref clock rate change, which event we detect here in the driver by means of the clocks event notifier. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Paul Burton <paulburton@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: linux-mips@vger.kernel.org Cc: linux-rtc@vger.kernel.org Cc: devicetree@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20200521204818.25436-9-Sergey.Semin@baikalelectronics.ru
2020-05-22clocksource/drivers/rda: drop redundant Kconfig dependencyJohan Hovold
Since commit 2f8a26c166eb ("clocksource: Improve GENERIC_CLOCKEVENTS dependency") all clocksource drivers depend on GENERIC_CLOCKEVENTS so drop the redundant attribute from the RDA-timer entry which was added later. Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20200513122548.16974-1-johan@kernel.org
2020-04-27clocksource/drivers/versatile: Allow CONFIG_CLKSRC_VERSATILE to be disabledRob Herring
The timer-versatile driver provides a sched_clock for certain Arm Ltd. reference platforms. Specifically, it is used on Versatile and 32-bit VExpress. It is not needed for those platforms with an arch timer (all the 64-bit ones) yet CONFIG_MFD_VEXPRESS_SYSREG does still need to be enabled. In that case, the timer-versatile can only be disabled when COMPILE_TEST is enabled which is not desirable. Let's use the sub-arch kconfig symbols instead. Realview platforms don't have the sysregs that this driver uses so correct the help text. Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20200417212045.16917-1-robh@kernel.org
2020-04-27clocksource/drivers/timer-microchip-pit64b: Select CONFIG_TIMER_OFMichael Ellerman
This driver is an OF driver, it depends on OF, and uses TIMER_OF_DECLARE, so it should select CONFIG_TIMER_OF. Without CONFIG_TIMER_OF enabled this can lead to warnings such as: powerpc-linux-ld: warning: orphan section `__timer_of_table' from `drivers/clocksource/timer-microchip-pit64b.o' being placed in section `__timer_of_table'. Because TIMER_OF_TABLES in vmlinux.lds.h doesn't emit anything into the linker script when CONFIG_TIMER_OF is not enabled. Fixes: 625022a5f160 ("clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support") Cc: stable@vger.kernel.org # v5.6+ Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20200426124356.3929682-1-mpe@ellerman.id.au
2020-02-27clocksource: Add driver for the Ingenic JZ47xx OSTMaarten ter Huurne
OST is the OS Timer, a 64-bit timer/counter with buffered reading. SoCs before the JZ4770 had (if any) a 32-bit OST; the JZ4770 and JZ4780 have a 64-bit OST. This driver will register both a clocksource and a sched_clock to the system. Signed-off-by: Maarten ter Huurne <maarten@treewalker.org> Signed-off-by: Paul Cercueil <paul@crapouillou.net> Tested-by: Mathieu Malaterre <malat@debian.org> Tested-by: Artur Rojek <contact@artur-rojek.eu> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20200212180408.30872-1-paul@crapouillou.net
2020-01-16clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B supportClaudiu Beznea
Add driver for Microchip PIT64B timer. Timer could be used in continuous mode or oneshot mode. The hardware has 2x32 bit registers for period emulating a 64 bit timer. The LSB_PR and MSB_PR registers are used to set the period value (compare value). TLSB and TMSB keeps the current value of the counter. After a compare the TLSB and TMSB register resets. The driver uses PIT64B timer for clocksource or clockevent. First requested timer would be registered as clockevent, second one would be registered as clocksource. Individual PIT64B hardware resources were used for clocksource and clockevent to be able to support high resolution timers with this hardware implementation. Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/1576235962-30123-3-git-send-email-claudiu.beznea@microchip.com
2020-01-16clocksource: Fix Kconfig miscuesRandy Dunlap
Fix lots of typo, spelling, punctuation, and grammar miscues in drivers/clocksource/Kconfig. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Stephen Boyd <sboyd@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/4deb42a9-82f2-72f9-891f-972a9a399f4f@infradead.org
2020-01-16clocksource: Fix Kconfig indentationKrzysztof Kozlowski
Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20191120134236.15959-1-krzk@kernel.org
2019-11-04clocksource/drivers/renesas-ostm: Convert to timer_ofGeert Uytterhoeven
Convert the Renesas OSTM driver to use the timer_of framework. This reduces the driver object size by 367 bytes (with gcc 7.4.0). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20191016144747.29538-4-geert+renesas@glider.be
2019-09-22Merge tag 'mips_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linuxLinus Torvalds
Pull MIPS updates from Paul Burton: "Main MIPS changes: - boot_mem_map is removed, providing a nice cleanup made possible by the recent removal of bootmem. - Some fixes to atomics, in general providing compiler barriers for smp_mb__{before,after}_atomic plus fixes specific to Loongson CPUs or MIPS32 systems using cmpxchg64(). - Conversion to the new generic VDSO infrastructure courtesy of Vincenzo Frascino. - Removal of undefined behavior in set_io_port_base(), fixing the behavior of some MIPS kernel configurations when built with recent clang versions. - Initial MIPS32 huge page support, functional on at least Ingenic SoCs. - pte_special() is now supported for some configurations, allowing among other things generic fast GUP to be used. - Miscellaneous fixes & cleanups. And platform specific changes: - Major improvements to Ingenic SoC support from Paul Cercueil, mostly enabled by the inclusion of the new TCU (timer-counter unit) drivers he's spent a very patient year or so working on. Plus some fixes for X1000 SoCs from Zhou Yanjie. - Netgear R6200 v1 systems are now supported by the bcm47xx platform. - DT updates for BMIPS, Lantiq & Microsemi Ocelot systems" * tag 'mips_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (89 commits) MIPS: Detect bad _PFN_SHIFT values MIPS: Disable pte_special() for MIPS32 with RiXi MIPS: ralink: deactivate PCI support for SOC_MT7621 mips: compat: vdso: Use legacy syscalls as fallback MIPS: Drop Loongson _CACHE_* definitions MIPS: tlbex: Remove cpu_has_local_ebase MIPS: tlbex: Simplify r3k check MIPS: Select R3k-style TLB in Kconfig MIPS: PCI: refactor ioc3 special handling mips: remove ioremap_cachable mips/atomic: Fix smp_mb__{before,after}_atomic() mips/atomic: Fix loongson_llsc_mb() wreckage mips/atomic: Fix cmpxchg64 barriers MIPS: Octeon: remove duplicated include from dma-octeon.c firmware: bcm47xx_nvram: Allow COMPILE_TEST firmware: bcm47xx_nvram: Correct size_t printf format MIPS: Treat Loongson Extensions as ASEs MIPS: Remove dev_err() usage after platform_get_irq() MIPS: dts: mscc: describe the PTP ready interrupt MIPS: dts: mscc: describe the PTP register range ...
2019-08-27clocksource/drivers/tcb_clksrc: Register delay timerAlexandre Belloni
Implement and register delay timer to allow get_cycles() to work properly. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-08-08clocksource: Add a new timer-ingenic driverPaul Cercueil
This driver handles the TCU (Timer Counter Unit) present on the Ingenic JZ47xx SoCs, and provides the kernel with a system timer, a clocksource and a sched_clock. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Tested-by: Mathieu Malaterre <malat@debian.org> Tested-by: Artur Rojek <contact@artur-rojek.eu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <jhogan@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lee Jones <lee.jones@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: linux-clk@vger.kernel.org Cc: od@zcrc.me
2019-06-25clocksource/drivers/davinci: Add support for clockeventsBartosz Golaszewski
Currently the clocksource and clockevent support for davinci platforms lives in mach-davinci. It hard-codes many things, uses global variables, implements functionalities unused by any platform and has code fragments scattered across many (often unrelated) files. Implement a new, modern and simplified timer driver and put it into drivers/clocksource. We still need to support legacy board files so export a config structure and a function that allows machine code to register the timer. The timer we're using is 64-bit but can be programmed in dual 32-bit mode (both chained and unchained). On all davinci SoCs except for da830 we're using both halves. Lower half for clockevents and upper half for clocksource. On da830 we're using the lower half for both with the help of a compare register. This patch contains the core code and support for clockevent. The clocksource code will be included in a subsequent patch. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-06-25clocksource/drivers/sysctr: Add nxp system counter timer driver supportBai Ping
The system counter (sys_ctr) is a programmable system counter which provides a shared time base to the Cortex A15, A7, A53 etc cores. It is intended for use in applications where the counter is always powered on and supports multiple, unrelated clocks. The sys_ctr hardware supports: - 56-bit counter width (roll-over time greater than 40 years) - compare frame(64-bit compare value) contains programmable interrupt generation when compare value <= counter value. [dlezcano] Fixed over 80 chars length warning Signed-off-by: Bai Ping <ping.bai@nxp.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-06-25clocksource/drivers/tegra: Support COMPILE_TEST universallyDmitry Osipenko
Remove build dependency on ARM for compile-testing to allow non-arch specific build-bots (like Intel's test robot) to compile the driver and report about problems. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Acked-By: Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-19Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull clocksource updates from Ingo Molnar: "Misc clocksource/clockevent driver updates that came in a bit late but are ready for v5.2" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: misc: atmel_tclib: Do not probe already used TCBs clocksource/drivers/timer-atmel-tcb: Convert tc_clksrc_suspend|resume() to static clocksource/drivers/tcb_clksrc: Rename the file for consistency clocksource/drivers/timer-atmel-pit: Rework Kconfig option clocksource/drivers/tcb_clksrc: Move Kconfig option ARM: at91: Implement clocksource selection clocksource/drivers/tcb_clksrc: Use tcb as sched_clock clocksource/drivers/tcb_clksrc: Stop depending on atmel_tclib ARM: at91: move SoC specific definitions to SoC folder clocksource/drivers/timer-milbeaut: Cleanup common register accesses clocksource/drivers/timer-milbeaut: Add shutdown function clocksource/drivers/timer-milbeaut: Fix to enable one-shot timer clocksource/drivers/tegra: Rework for compensation of suspend time clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804 clocksource/drivers/sun4i: Add a compatible for suniv dt-bindings: timer: Add Allwinner suniv timer
2019-05-15Merge branch 'fixes' into arm/socOlof Johansson
Merge in a few pending fixes from pre-5.1 that didn't get sent in: MAINTAINERS: update arch/arm/mach-davinci ARM: dts: ls1021: Fix SGMII PCS link remaining down after PHY disconnect ARM: dts: imx6q-logicpd: Reduce inrush current on USBH1 ARM: dts: imx6q-logicpd: Reduce inrush current on start ARM: dts: imx: Fix the AR803X phy-mode ARM: dts: sun8i: a33: Reintroduce default pinctrl muxing arm64: dts: allwinner: a64: Rename hpvcc-supply to cpvdd-supply ARM: sunxi: fix a leaked reference by adding missing of_node_put ARM: sunxi: fix a leaked reference by adding missing of_node_put Signed-off-by: Olof Johansson <olof@lixom.net>
2019-05-02clocksource/drivers/timer-atmel-pit: Rework Kconfig optionAlexandre Belloni
Allow building the PIT driver when COMPILE_TEST is enabled. Also remove its default value so it can be disabled. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-05-02clocksource/drivers/tcb_clksrc: Move Kconfig optionAlexandre Belloni
Move the ATMEL_TCB_CLKSRC option to drivers/clocksource and make it silent if COMPILE_TEST is not selected. Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-05-02clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804David Abdurachmanov
This is only used on arm and arm64 platforms. Add COMPILE_TEST option. Tested with 5.1-rc3+ on Fedora/RISCV. CONFIG_ARM_TIMER_SP804 no more shows up in riscv config. Signed-off-by: David Abdurachmanov <david.abdurachmanov@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-04-23clocksource/drivers/ixp4xx: Add driverLinus Walleij
This adds a new slightly rewritten timer driver for the Intel IXP4xx clocksource, clockevent and delay timer. Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-11clocksource/drivers/npcm: select TIMER_OFArnd Bergmann
When this is disabled, we get a link failure: drivers/clocksource/timer-npcm7xx.o: In function `npcm7xx_timer_init': timer-npcm7xx.c:(.init.text+0xf): undefined reference to `timer_of_init' Fixes: 1c00289ecd12 ("clocksource/drivers/npcm: Add NPCM7xx timer driver") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-03-06Merge tag 'armsoc-newsoc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull ARM new SoC family support from Arnd Bergmann: "Two new SoC families are added this time. Sugaya Taichi submitted support for the Milbeaut SoC family from Socionext and explains: "SC2000 is a SoC of the Milbeaut series. equipped with a DSP optimized for computer vision. It also features advanced functionalities such as 360-degree, real-time spherical stitching with multi cameras, image stabilization for without mechanical gimbals, and rolling shutter correction. More detail is below: https://www.socionext.com/en/products/assp/milbeaut/SC2000.html" Interestingly, this one has a history dating back to older chips made by Socionext and previously Matsushita/Panasonic based on their own mn10300 CPU architecture that was removed from the kernel last year. Manivannan Sadhasivam adds support for another SoC family, this is the Bitmain BM1880 chip used in the Sophon Edge TPU developer board. The chip is intended for Deep Learning applications, and comes with dual-core Arm Cortex-A53 to run Linux as well as a RISC-V microcontroller core to control the tensor unit. For the moment, the TPU is not accessible in mainline Linux, so we treat it as a generic Arm SoC. More information is available at https://www.sophon.ai/" * tag 'armsoc-newsoc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: ARM: multi_v7_defconfig: add ARCH_MILBEAUT and ARCH_MILBEAUT_M10V ARM: configs: Add Milbeaut M10V defconfig ARM: dts: milbeaut: Add device tree set for the Milbeaut M10V board clocksource/drivers/timer-milbeaut: Introduce timer for Milbeaut SoCs dt-bindings: timer: Add Milbeaut M10V timer description ARM: milbeaut: Add basic support for Milbeaut m10v SoC dt-bindings: Add documentation for Milbeaut SoCs dt-bindings: arm: Add SMP enable-method for Milbeaut dt-bindings: sram: milbeaut: Add binding for Milbeaut smp-sram MAINTAINERS: Add entry for Bitmain SoC platform arm64: dts: bitmain: Add Sophon Egde board support arm64: dts: bitmain: Add BM1880 SoC support arm64: Add ARCH_BITMAIN platform dt-bindings: arm: Document Bitmain BM1880 SoC
2019-03-01clocksource/drivers/timer-milbeaut: Introduce timer for Milbeaut SoCsSugaya Taichi
Add timer driver for Milbeaut SoCs series. The timer has two 32-bit width down counters, one of which is configured as a clockevent device and the other is configured as a clock source. Signed-off-by: Sugaya Taichi <sugaya.taichi@socionext.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-02-23clocksource/drivers/tegra: Add Tegra210 timer supportJoseph Lo
Add support for the Tegra210 timer that runs at oscillator clock (TMR10-TMR13). We need these timers to work as clock event device and to replace the ARMv8 architected timer due to it can't survive across the power cycle of the CPU core or CPUPORESET signal. So it can't be a wake-up source when CPU suspends in power down state. Also convert the original driver to use timer-of API. Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Joseph Lo <josephl@nvidia.com> Acked-by: Thierry Reding <treding@nvidia.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-02-23clocksource/drivers/arch_timer: Workaround for Allwinner A64 timer instabilitySamuel Holland
The Allwinner A64 SoC is known[1] to have an unstable architectural timer, which manifests itself most obviously in the time jumping forward a multiple of 95 years[2][3]. This coincides with 2^56 cycles at a timer frequency of 24 MHz, implying that the time went slightly backward (and this was interpreted by the kernel as it jumping forward and wrapping around past the epoch). Investigation revealed instability in the low bits of CNTVCT at the point a high bit rolls over. This leads to power-of-two cycle forward and backward jumps. (Testing shows that forward jumps are about twice as likely as backward jumps.) Since the counter value returns to normal after an indeterminate read, each "jump" really consists of both a forward and backward jump from the software perspective. Unless the kernel is trapping CNTVCT reads, a userspace program is able to read the register in a loop faster than it changes. A test program running on all 4 CPU cores that reported jumps larger than 100 ms was run for 13.6 hours and reported the following: Count | Event -------+--------------------------- 9940 | jumped backward 699ms 268 | jumped backward 1398ms 1 | jumped backward 2097ms 16020 | jumped forward 175ms 6443 | jumped forward 699ms 2976 | jumped forward 1398ms 9 | jumped forward 356516ms 9 | jumped forward 357215ms 4 | jumped forward 714430ms 1 | jumped forward 3578440ms This works out to a jump larger than 100 ms about every 5.5 seconds on each CPU core. The largest jump (almost an hour!) was the following sequence of reads: 0x0000007fffffffff → 0x00000093feffffff → 0x0000008000000000 Note that the middle bits don't necessarily all read as all zeroes or all ones during the anomalous behavior; however the low 10 bits checked by the function in this patch have never been observed with any other value. Also note that smaller jumps are much more common, with backward jumps of 2048 (2^11) cycles observed over 400 times per second on each core. (Of course, this is partially explained by lower bits rolling over more frequently.) Any one of these could have caused the 95 year time skip. Similar anomalies were observed while reading CNTPCT (after patching the kernel to allow reads from userspace). However, the CNTPCT jumps are much less frequent, and only small jumps were observed. The same program as before (except now reading CNTPCT) observed after 72 hours: Count | Event -------+--------------------------- 17 | jumped backward 699ms 52 | jumped forward 175ms 2831 | jumped forward 699ms 5 | jumped forward 1398ms Further investigation showed that the instability in CNTPCT/CNTVCT also affected the respective timer's TVAL register. The following values were observed immediately after writing CNVT_TVAL to 0x10000000: CNTVCT | CNTV_TVAL | CNTV_CVAL | CNTV_TVAL Error --------------------+------------+--------------------+----------------- 0x000000d4a2d8bfff | 0x10003fff | 0x000000d4b2d8bfff | +0x00004000 0x000000d4a2d94000 | 0x0fffffff | 0x000000d4b2d97fff | -0x00004000 0x000000d4a2d97fff | 0x10003fff | 0x000000d4b2d97fff | +0x00004000 0x000000d4a2d9c000 | 0x0fffffff | 0x000000d4b2d9ffff | -0x00004000 The pattern of errors in CNTV_TVAL seemed to depend on exactly which value was written to it. For example, after writing 0x10101010: CNTVCT | CNTV_TVAL | CNTV_CVAL | CNTV_TVAL Error --------------------+------------+--------------------+----------------- 0x000001ac3effffff | 0x1110100f | 0x000001ac4f10100f | +0x1000000 0x000001ac40000000 | 0x1010100f | 0x000001ac5110100f | -0x1000000 0x000001ac58ffffff | 0x1110100f | 0x000001ac6910100f | +0x1000000 0x000001ac66000000 | 0x1010100f | 0x000001ac7710100f | -0x1000000 0x000001ac6affffff | 0x1110100f | 0x000001ac7b10100f | +0x1000000 0x000001ac6e000000 | 0x1010100f | 0x000001ac7f10100f | -0x1000000 I was also twice able to reproduce the issue covered by Allwinner's workaround[4], that writing to TVAL sometimes fails, and both CVAL and TVAL are left with entirely bogus values. One was the following values: CNTVCT | CNTV_TVAL | CNTV_CVAL --------------------+------------+-------------------------------------- 0x000000d4a2d6014c | 0x8fbd5721 | 0x000000d132935fff (615s in the past) Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> ======================================================================== Because the CPU can read the CNTPCT/CNTVCT registers faster than they change, performing two reads of the register and comparing the high bits (like other workarounds) is not a workable solution. And because the timer can jump both forward and backward, no pair of reads can distinguish a good value from a bad one. The only way to guarantee a good value from consecutive reads would be to read _three_ times, and take the middle value only if the three values are 1) each unique and 2) increasing. This takes at minimum 3 counter cycles (125 ns), or more if an anomaly is detected. However, since there is a distinct pattern to the bad values, we can optimize the common case (1022/1024 of the time) to a single read by simply ignoring values that match the error pattern. This still takes no more than 3 cycles in the worst case, and requires much less code. As an additional safety check, we still limit the loop iteration to the number of max-frequency (1.2 GHz) CPU cycles in three 24 MHz counter periods. For the TVAL registers, the simple solution is to not use them. Instead, read or write the CVAL and calculate the TVAL value in software. Although the manufacturer is aware of at least part of the erratum[4], there is no official name for it. For now, use the kernel-internal name "UNKNOWN1". [1]: https://github.com/armbian/build/commit/a08cd6fe7ae9 [2]: https://forum.armbian.com/topic/3458-a64-datetime-clock-issue/ [3]: https://irclog.whitequark.org/linux-sunxi/2018-01-26 [4]: https://github.com/Allwinner-Homlet/H6-BSP4.9-linux/blob/master/drivers/clocksource/arm_arch_timer.c#L272 Acked-by: Maxime Ripard <maxime.ripard@bootlin.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Samuel Holland <samuel@sholland.org> Cc: stable@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-12-18clocksource/drivers/rda: Add clock driver for RDA8810PL SoCManivannan Sadhasivam
Add clock driver for RDA Micro RDA8810PL SoC supporting OSTIMER and HWTIMER. RDA8810PL has two independent timers: OSTIMER (56 bit) and HWTIMER (64 bit). Each timer provides optional interrupt support. In this driver, OSTIMER is used for clockevents and HWTIMER is used for clocksource. Signed-off-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-12-18clocksource/drivers/riscv_timer: Provide the sched_clockAnup Patel
Currently, we don't have a sched_clock registered for RISC-V systems. This means Linux time keeping will use jiffies (running at HZ) as the default sched_clock. To avoid this, we explicity provide sched_clock using RISC-V rdtime instruction (similar to riscv_timer clocksource). Signed-off-by: Anup Patel <anup@brainfault.org> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2018-12-18clocksource/drivers/arc_timer: Utilize generic sched_clockAlexey Brodkin
It turned out we used to use default implementation of sched_clock() from kernel/sched/clock.c which was as precise as 1/HZ, i.e. by default we had 10 msec granularity of time measurement. Now given ARC built-in timers are clocked with the same frequency as CPU cores we may get much higher precision of time tracking. Thus we switch to generic sched_clock which really reads ARC hardware counters. This is especially helpful for measuring short events. That's what we used to have: ------------------------------>8------------------------ $ perf stat /bin/sh -c /root/lmbench-master/bin/arc/hello > /dev/null Performance counter stats for '/bin/sh -c /root/lmbench-master/bin/arc/hello': 10.000000 task-clock (msec) # 2.832 CPUs utilized 1 context-switches # 0.100 K/sec 1 cpu-migrations # 0.100 K/sec 63 page-faults # 0.006 M/sec 3049480 cycles # 0.305 GHz 1091259 instructions # 0.36 insn per cycle 256828 branches # 25.683 M/sec 27026 branch-misses # 10.52% of all branches 0.003530687 seconds time elapsed 0.000000000 seconds user 0.010000000 seconds sys ------------------------------>8------------------------ And now we'll see: ------------------------------>8------------------------ $ perf stat /bin/sh -c /root/lmbench-master/bin/arc/hello > /dev/null Performance counter stats for '/bin/sh -c /root/lmbench-master/bin/arc/hello': 3.004322 task-clock (msec) # 0.865 CPUs utilized 1 context-switches # 0.333 K/sec 1 cpu-migrations # 0.333 K/sec 63 page-faults # 0.021 M/sec 2986734 cycles # 0.994 GHz 1087466 instructions # 0.36 insn per cycle 255209 branches # 84.947 M/sec 26002 branch-misses # 10.19% of all branches 0.003474829 seconds time elapsed 0.003519000 seconds user 0.000000000 seconds sys ------------------------------>8------------------------ Note how much more meaningful is the second output - time spent for execution pretty much matches number of cycles spent (we're runnign @ 1GHz here). Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>