kernel/linux.git/drivers/clocksource/Kconfig, branch v3.18.62

Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2014-10-09T10:35:05+00:00

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

ARM: meson6: clocksource: Add Meson6 timer support

2014-09-28T23:50:05+00:00

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 Signed-off-by: Carlo Caione Signed-off-by: Daniel Lezcano Reviewed-by: Matthias Brugger

ARM: at91: PIT: Move the driver to drivers/clocksource

2014-09-15T15:55:48+00:00

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 Acked-by: Boris BREZILLON Acked-by: Alexandre Belloni Acked-by: Daniel Lezcano Signed-off-by: Nicolas Ferre Conflicts: arch/arm/mach-at91/Kconfig arch/arm/mach-at91/Makefile

clocksource: exynos_mct: Only use 32-bits where possible

2014-07-23T10:02:41+00:00

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 Acked-by Vincent Guittot Signed-off-by: Kukjin Kim Signed-off-by: Daniel Lezcano

clocksource: Kconfig: Let EM_TIMER_STI depend on HAS_IOMEM

2014-07-23T10:02:33+00:00

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 Signed-off-by: Daniel Lezcano

clocksource: Add support for the Mediatek SoCs

2014-07-23T10:02:31+00:00

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 Acked-by: Thomas Gleixner Signed-off-by: Daniel Lezcano

clocksource: sh_mtu2: Tidy up Kconfig typo for MTU2

2014-07-23T10:02:29+00:00

It should be "MTU2" instead of "TMU2" Signed-off-by: Kuninori Morimoto Acked-by: Wolfram Sang Acked-by: Simon Horman Signed-off-by: Daniel Lezcano

clocksource: Add a Kconfig menu

2014-06-21T20:32:42+00:00

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 Cc: Daniel Lezcano Link: http://lkml.kernel.org/r/20140616114845.343e9960@endymion.delvare Signed-off-by: Thomas Gleixner

Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next

2014-06-04T22:57:20+00:00

Pull timer core updates from Thomas Gleixner: "This time you get nothing really exciting: - A huge update to the sh* clocksource drivers - Support for two more ARM SoCs - Removal of the deprecated setup_sched_clock() API - The usual pile of fixlets all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) clocksource: Add Freescale FlexTimer Module (FTM) timer support ARM: dts: vf610: Add Freescale FlexTimer Module timer node. clocksource: ftm: Add FlexTimer Module (FTM) Timer devicetree Documentation clocksource: sh_tmu: Remove unnecessary OOM messages clocksource: sh_mtu2: Remove unnecessary OOM messages clocksource: sh_cmt: Remove unnecessary OOM messages clocksource: em_sti: Remove unnecessary OOM messages clocksource: dw_apb_timer_of: Do not trace read_sched_clock clocksource: Fix clocksource_mmio_readX_down clocksource: Fix type confusion for clocksource_mmio_readX_Y clocksource: sh_tmu: Fix channel IRQ retrieval in legacy case clocksource: qcom: Implement read_current_timer for udelay ntp: Make is_error_status() use its argument ntp: Convert simple_strtol to kstrtol timer_stats/doc: Fix /proc/timer_stats documentation sched_clock: Remove deprecated setup_sched_clock() API ARM: sun6i: a31: Add support for the High Speed Timers clocksource: sun5i: Add support for reset controller clocksource: efm32: use $vendor,$device scheme for compatible string KConfig: Vexpress: build the ARM_GLOBAL_TIMER with vexpress platform ...

ARM: vexpress: refine dependencies for new code

2014-05-26T19:26:52+00:00

The versatile express changes for 3.16 introduced a number of build regressions for randconfig kernels by not tracking dependencies between the components right. This patch tries to rectify that: * the mach-vexpress code cannot link without the syscfg driver, which in turn needs MFD_VEXPRESS_SYSREG * various drivers call devm_regmap_init_vexpress_config(), which has to be exported so it can be used by loadable modules * the configuration bus uses OF DT helper functions that are not available to platforms disable CONFIG_OF * The sysreg driver exports GPIOs through gpiolib, which can be disabled on some platforms. * The clocksource code cannot be built on platforms that don't use modern timekeeping but rely on gettimeoffset. Signed-off-by: Arnd Bergmann