linux/drivers/clocksource
David Woodhouse 70e6b7d9ae x86/i8253: Disable PIT timer 0 when not in use
Leaving the PIT interrupt running can cause noticeable steal time for
virtual guests. The VMM generally has a timer which toggles the IRQ input
to the PIC and I/O APIC, which takes CPU time away from the guest. Even
on real hardware, running the counter may use power needlessly (albeit
not much).

Make sure it's turned off if it isn't going to be used.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mhkelley@outlook.com>
Link: https://lore.kernel.org/all/20240802135555.564941-1-dwmw2@infradead.org
2024-08-02 18:27:05 +02:00
..
acpi_pm.c clocksource: Verify HPET and PMTMR when TSC unverified 2023-02-02 14:23:02 -08:00
arc_timer.c clocksource/drivers/arc_timer: Eliminate redefined macro error 2021-10-16 22:15:01 +02:00
arm_arch_timer.c clocksource/drivers/arm_arch_timer: Remove unnecessary ‘0’ values from irq 2024-07-12 16:07:05 +02:00
arm_global_timer.c clocksource/driver/arm_global_timer: Remove unnecessary ‘0’ values from err 2024-07-12 16:07:05 +02:00
armv7m_systick.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
asm9260_timer.c clocksource/drivers/asm9260: Add a check for of_clk_get 2019-11-04 10:40:10 +01:00
bcm2835_timer.c clocksource: Explicitly include correct DT includes 2023-08-28 13:30:57 -05:00
bcm_kona_timer.c clocksource/drivers/bcm_kona: Convert to SPDX identifier 2022-05-18 11:08:59 +02:00
clksrc_st_lpc.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
clksrc-dbx500-prcmu.c timekeeping, clocksource: Fix various typos in comments 2021-03-22 23:06:48 +01:00
clps711x-timer.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
dummy_timer.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
dw_apb_timer_of.c clocksource/drivers/dw_apb_timer_of: Fix probe failure 2021-12-10 17:46:54 +01:00
dw_apb_timer.c clocksource: dw_apb_timer: Make CPU-affiliation being optional 2020-05-23 00:02:41 +02:00
em_sti.c clocksource: remove MODULE_LICENSE in non-modules 2023-04-13 13:13:51 -07:00
exynos_mct.c clocksource/drivers/exynos_mct: Explicitly return 0 for shared timer 2023-04-24 16:56:13 +02:00
hyperv_timer.c hyperv-tlfs: Change prefix of generic HV_REGISTER_* MSRs to HV_MSR_* 2024-03-04 06:59:18 +00:00
i8253.c x86/i8253: Disable PIT timer 0 when not in use 2024-08-02 18:27:05 +02:00
ingenic-ost.c clocksource/drivers/ingenic-ost: Define pm functions properly in platform_driver struct 2022-12-01 11:56:36 +01:00
ingenic-sysost.c clocksource/drivers/ingenic: Use bitfield macro helpers 2021-08-14 02:44:35 +02:00
ingenic-timer.c clocksource/drivers/ingenic-timer: Use pm_sleep_ptr() macro 2023-06-19 16:17:42 +02:00
jcore-pit.c clocksource/drivers/jcore: Convert to SPDX identifier 2022-05-18 11:08:59 +02:00
Kconfig clocksource/drivers/realtek: Add timer driver for rtl-otto platforms 2024-07-12 16:07:06 +02:00
Makefile clocksource/drivers/realtek: Add timer driver for rtl-otto platforms 2024-07-12 16:07:06 +02:00
mips-gic-timer.c clocksource/drivers/mips-gic-timer: Correct sched_clock width 2024-07-12 16:07:05 +02:00
mmio.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
mps2-timer.c clocksource/drivers/mps2-timer: Use semicolons rather than commas to separate statements 2020-10-01 10:07:26 +02:00
mxs_timer.c clocksource/drivers/mxs_timer: Add missing semicolon when DEBUG is defined 2021-01-18 22:28:59 +01:00
nomadik-mtu.c clocksource: Explicitly include correct DT includes 2023-08-28 13:30:57 -05:00
numachip.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
renesas-ostm.c clocksource/drivers/renesas-ostm: Avoid reprobe after successful early probe 2024-05-10 10:41:52 +02:00
samsung_pwm_timer.c of: remove internal arguments from of_property_for_each_u32() 2024-07-25 06:53:47 -05:00
scx200_hrt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
sh_cmt.c clocksource/drivers/sh_cmt: Address race condition for clock events 2024-07-12 16:07:05 +02:00
sh_mtu2.c Timekeeping and clocksource/event driver updates the second batch: 2023-04-29 10:24:30 -07:00
sh_tmu.c clocksource: remove MODULE_LICENSE in non-modules 2023-04-13 13:13:51 -07:00
timer-armada-370-xp.c clocksource/drivers/armada-370-xp: Convert to SPDX identifier 2022-05-18 11:08:59 +02:00
timer-atmel-pit.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
timer-atmel-st.c clocksource/drivers/atmel-st: Remove useless 'status' 2020-04-15 10:57:15 +02:00
timer-atmel-tcb.c clocksource/drivers/timer-atmel-tcb: Fix initialization on SAM9 hardware 2023-10-13 12:56:50 +02:00
timer-cadence-ttc.c clocksource/drivers/cadence-ttc: Fix some kernel-doc warnings 2023-12-27 15:37:11 +01:00
timer-clint.c riscv: Use IPIs for remote cache/TLB flushes by default 2024-04-29 10:49:26 -07:00
timer-cs5535.c clocksource/drivers/timer-cs5535: Request irq with non-NULL dev_id 2020-03-12 19:23:06 +01:00
timer-davinci.c clocksource/drivers/davinci: Fix memory leak in davinci_timer_register when init fails 2023-04-24 16:56:13 +02:00
timer-digicolor.c clocksource/drivers/digicolor: Convert to SPDX identifier 2022-05-18 11:08:59 +02:00
timer-ep93xx.c clocksource/drivers/ep93xx: Fix error handling during probe 2023-12-27 15:37:11 +01:00
timer-fsl-ftm.c timekeeping, clocksource: Fix various typos in comments 2021-03-22 23:06:48 +01:00
timer-fttmr010.c clocksource/drivers/fttmr010: Pass around less pointers 2021-08-14 10:49:49 +02:00
timer-goldfish.c clocksource/drivers: Add a goldfish-timer clocksource 2022-04-11 11:48:01 +02:00
timer-gx6605s.c clocksource/drivers/timer-gx6605s: Fixup counter reload 2020-08-24 13:01:39 +02:00
timer-gxp.c clocksource: Explicitly include correct DT includes 2023-08-28 13:30:57 -05:00
timer-imx-gpt.c clocksource/drivers/imx: Fix -Wunused-but-set-variable warning 2024-01-22 13:11:02 +01:00
timer-imx-sysctr.c clocksource/drivers/imx-sysctr: Add i.MX95 support 2024-02-18 10:45:36 +01:00
timer-imx-tpm.c clocksource/drivers/imx-tpm: Move tpm_read_sched_clock() under CONFIG_ARM 2022-03-07 18:27:22 +01:00
timer-integrator-ap.c clocksource: Explicitly include correct DT includes 2023-08-28 13:30:57 -05:00
timer-ixp4xx.c clocksource/drivers/ixp4xx: Drop boardfile probe path 2022-05-18 11:08:52 +02:00
timer-keystone.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
timer-loongson1-pwm.c clocksource/drivers/loongson1: Set variable ls1x_timer_lock storage-class-specifier to static 2023-08-18 12:13:03 +02:00
timer-lpc32xx.c clocksource/drivers/lpc32xx: Convert to SPDX identifier 2022-05-18 11:08:59 +02:00
timer-mediatek-cpux.c clocksource/drivers/timer-mediatek: Split out CPUXGPT timers 2023-04-24 16:56:13 +02:00
timer-mediatek.c clocksource/drivers/timer-mediatek: Split out CPUXGPT timers 2023-04-24 16:56:13 +02:00
timer-meson6.c clocksource: Replace setup_irq() by request_irq() 2020-02-27 12:15:24 +01:00
timer-microchip-pit64b.c clocksource/drivers/timer-microchip-pit64b: Add delay timer 2023-02-13 13:10:17 +01:00
timer-milbeaut.c clocksource/drivers/timer-milbeaut: Cleanup common register accesses 2019-05-02 21:55:58 +02:00
timer-mp-csky.c
timer-msc313e.c clocksource/drivers/msc313e: Add support for ssd20xd-based platforms 2021-12-20 13:28:39 +01:00
timer-npcm7xx.c clocksource/drivers/timer-npcm7xx: Enable timer 1 clock before use 2022-12-02 12:48:28 +01:00
timer-of.c clocksource/drivers/timer-of: Check return value of of_iomap in timer_of_base_init() 2022-03-07 19:21:25 +01:00
timer-of.h
timer-orion.c clocksource/drivers/orion: Convert to SPDX identifier 2022-05-18 11:08:59 +02:00
timer-owl.c clocksource/drivers/owl: Improve owl_timer_init fail messages 2020-02-27 09:42:00 +01:00
timer-pistachio.c clocksource/drivers/pistachio: Convert to SPDX identifier 2022-05-18 11:08:59 +02:00
timer-probe.c treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
timer-pxa.c clocksource: Replace setup_irq() by request_irq() 2020-02-27 12:15:24 +01:00
timer-qcom.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
timer-rda.c
timer-riscv.c A set of updates for clocksource and clockevent drivers: 2024-03-23 14:42:45 -07:00
timer-rockchip.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
timer-rtl-otto.c clocksource/drivers/realtek: Add timer driver for rtl-otto platforms 2024-07-12 16:07:06 +02:00
timer-sp804.c clocksource/drivers/sp804: Do not use timer namespace for timer_shutdown() function 2022-11-24 15:09:10 +01:00
timer-sp.h clocksource/drivers/sp804: Enable Hisilicon sp804 timer 64bit mode 2020-09-24 10:51:04 +02:00
timer-sprd.c
timer-stm32-lp.c Timekeeping and clocksource/event driver updates the second batch: 2023-04-29 10:24:30 -07:00
timer-stm32.c clocksource/drivers/stm32: Fix all kernel-doc warnings 2024-01-22 13:15:38 +01:00
timer-sun4i.c clocksource/drivers/timer-sun4i: Add CLOCK_EVT_FEAT_DYNIRQ 2023-02-13 13:10:17 +01:00
timer-sun5i.c clocksource/drivers/sun5i: Remove surplus dev_err() when using platform_get_irq() 2023-10-11 12:06:41 +02:00
timer-tegra186.c clocksource: Explicitly include correct DT includes 2023-08-28 13:30:57 -05:00
timer-tegra.c clocksource/drivers/tegra: Set up maximum-ticks limit properly 2019-06-25 19:49:18 +02:00
timer-ti-32k.c clocksource/drivers/ti-32K: Fix misuse of "/**" comment 2024-01-22 13:16:32 +01:00
timer-ti-dm-systimer.c clocksource/drivers/ti: Use of_property_read_bool() for boolean properties 2023-04-24 16:56:14 +02:00
timer-ti-dm.c clocksource/drivers/timer-ti-dm: Remove an unused field in struct dmtimer 2024-05-10 10:41:52 +02:00
timer-versatile.c clocksource/drivers/timer-versatile: Clear OF_POPULATED flag 2020-05-23 00:03:25 +02:00
timer-vf-pit.c timekeeping, clocksource: Fix various typos in comments 2021-03-22 23:06:48 +01:00
timer-vt8500.c clocksource: Replace setup_irq() by request_irq() 2020-02-27 12:15:24 +01:00
timer-zevio.c clocksource: Replace setup_irq() by request_irq() 2020-02-27 12:15:24 +01:00