OpenCloudOS-Kernel/drivers/clocksource
Oliver Upton 44affb5b69 clocksource/drivers/arm_arch_timer: Fix masking for high freq counters
Unfortunately, the architecture provides no means to determine the bit
width of the system counter. However, we do know the following from the
specification:

 - the system counter is at least 56 bits wide
 - Roll-over time of not less than 40 years

To date, the arch timer driver has depended on the first property,
assuming any system counter to be 56 bits wide and masking off the rest.
However, combining a narrow clocksource mask with a high frequency
counter could result in prematurely wrapping the system counter by a
significant margin. For example, a 56 bit wide, 1GHz system counter
would wrap in a mere 2.28 years!

This is a problem for two reasons: v8.6+ implementations are required to
provide a 64 bit, 1GHz system counter. Furthermore, before v8.6,
implementers may select a counter frequency of their choosing.

Fix the issue by deriving a valid clock mask based on the second
property from above. Set the floor at 56 bits, since we know no system
counter is narrower than that.

[maz: fixed width computation not to lose the last bit, added
      max delta generation for the timer]

Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210807191428.3488948-1-oupton@google.com
Link: https://lore.kernel.org/r/20211017124225.3018098-13-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: hongrongxuan <hongrongxuan@huawei.com>
2024-06-12 13:16:41 +08:00
..
Kconfig tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
Makefile clocksource: Add a new timer-ingenic driver 2019-08-08 15:30:08 -07:00
acpi_pm.c tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
arc_timer.c Merge branch 'timers/vdso' into timers/core 2019-07-03 10:50:21 +02:00
arm_arch_timer.c clocksource/drivers/arm_arch_timer: Fix masking for high freq counters 2024-06-12 13:16:41 +08:00
arm_global_timer.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +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 tkernel: add base tlinux kernel interfaces 2024-06-11 20:09:33 +08:00
bcm2835_timer.c tkernel: add base tlinux kernel interfaces 2024-06-11 20:09:33 +08:00
bcm_kona_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
clksrc-dbx500-prcmu.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 197 2019-05-30 11:29:22 -07:00
clksrc_st_lpc.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
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.c ock: sync codes to ock 5.4.119-20.0009.21 2024-06-11 20:27:38 +08:00
dw_apb_timer_of.c ock: sync codes to ock 5.4.119-20.0009.21 2024-06-11 20:27:38 +08:00
em_sti.c clocksource: Remove dev_err() usage after platform_get_irq() 2019-08-27 00:31:39 +02:00
exynos_mct.c Merge branch 'timers/vdso' into timers/core 2019-07-03 10:50:21 +02:00
h8300_timer8.c ock: sync codes to ock 5.4.119-20.0009.21 2024-06-11 20:27:38 +08:00
h8300_timer16.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
h8300_tpu.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hyperv_timer.c tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
i8253.c clockevents/drivers/i8253: Add support for PIT shutdown quirk 2018-11-04 11:04:46 +01:00
ingenic-timer.c clocksource: Add a new timer-ingenic driver 2019-08-08 15:30:08 -07:00
jcore-pit.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
mips-gic-timer.c clocksource/drivers/mips-gic-timer: Make gic_compare_irqaction static 2019-03-22 22:59:33 +01:00
mmio.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
mps2-timer.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
mxs_timer.c ock: sync codes to ock 5.4.119-20.0009.21 2024-06-11 20:27:38 +08:00
nomadik-mtu.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
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: Use DIV_ROUND_CLOSEST() helper 2019-08-27 00:31:39 +02:00
samsung_pwm_timer.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
scx200_hrt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
sh_cmt.c tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
sh_mtu2.c clocksource/drivers/sh_mtu2: Do not loop using platform_get_irq_by_name() 2019-10-18 07:55:16 +02:00
sh_tmu.c clocksource: Remove dev_err() usage after platform_get_irq() 2019-08-27 00:31:39 +02:00
timer-armada-370-xp.c clocksource/drivers: Unify the names to timer-* format 2018-10-03 14:37:02 +02:00
timer-atcpit100.c clocksource/drivers: Set clockevent device cpumask to cpu_possible_mask 2018-07-26 11:26:30 +02:00
timer-atlas7.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 4 2019-05-21 11:28:40 +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 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
timer-atmel-tcb.c clocksource/drivers/tcb_clksrc: Register delay timer 2019-08-27 00:31:39 +02:00
timer-cadence-ttc.c ock: sync codes to ock 5.4.119-20.0009.21 2024-06-11 20:27:38 +08:00
timer-cs5535.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
timer-davinci.c tkernel: add base tlinux kernel interfaces 2024-06-11 20:09:33 +08:00
timer-digicolor.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-efm32.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
timer-fsl-ftm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
timer-fttmr010.c clocksource/drivers/fttmr010: Fix invalid interrupt register access 2018-12-18 22:22:23 +01:00
timer-gx6605s.c ock: sync codes to ock 5.4.119-20.0009.21 2024-06-11 20:27:38 +08:00
timer-imx-gpt.c clocksource/drivers/imx-gpt: Remove unnecessary irq protection 2018-12-18 22:22:23 +01:00
timer-imx-sysctr.c clocksource/drivers/imx-sysctr: Add internal clock divider handle 2019-08-27 00:31:39 +02:00
timer-imx-tpm.c clocksource/drivers/timer-imx-tpm: Specify clock name for timer-of 2018-12-18 22:22:23 +01:00
timer-integrator-ap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
timer-ixp4xx.c tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
timer-keystone.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
timer-lpc32xx.c clocksource/drivers: Unify the names to timer-* format 2018-10-03 14:37:02 +02:00
timer-mediatek.c clocksource/drivers/mediatek: Fix error handling 2019-10-16 17:04:50 +02:00
timer-meson6.c clocksource/drivers/timer-meson6: Update with SPDX Licence identifier 2019-06-25 19:49:18 +02:00
timer-milbeaut.c clocksource/drivers/timer-milbeaut: Cleanup common register accesses 2019-05-02 21:55:58 +02:00
timer-mp-csky.c clocksource/drivers/c-sky: fixup ftrace call-graph panic 2018-12-31 23:17:23 +08:00
timer-npcm7xx.c clocksource/drivers/npcm: Fix GENMASK and timer operation 2019-08-27 00:31:39 +02:00
timer-nps.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-of.c tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
timer-of.h clocksource/drivers/timer-of: Store the device node pointer in 'struct timer_of' 2018-01-08 17:57:24 +01:00
timer-orion.c ock: sync codes to ock 5.4.119-20.0009.21 2024-06-11 20:27:38 +08:00
timer-owl.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
timer-oxnas-rps.c tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
timer-pistachio.c clocksource/drivers: Unify the names to timer-* format 2018-10-03 14:37:02 +02:00
timer-prima2.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 4 2019-05-21 11:28:40 +02:00
timer-probe.c clocksource/drivers: Do not warn on probe defer 2019-08-27 00:31:39 +02:00
timer-pxa.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
timer-qcom.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
timer-rda.c clocksource/drivers/rda: Add clock driver for RDA8810PL SoC 2018-12-18 22:22:23 +01:00
timer-riscv.c tkernel: add base tlinux kernel interfaces 2024-06-11 20:09:33 +08:00
timer-rockchip.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
timer-sp.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
timer-sp804.c tkernel: sync code to the same with tk4 pub/lts/0017-kabi 2024-06-12 13:13:20 +08:00
timer-sprd.c clocksource/drivers/sprd: Register one always-on timer to compensate suspend time 2018-07-26 11:26:34 +02:00
timer-stm32.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
timer-sun4i.c clocksource: sun4i: Add missing compatibles 2019-08-27 00:31:39 +02:00
timer-sun5i.c clocksource/drivers/sun5i: Fail gracefully when clock rate is unavailable 2019-02-23 12:13:45 +01:00
timer-tango-xtal.c clocksource/drivers/tango-xtal: Rename the file for consistency 2019-02-23 12:13:45 +01:00
timer-tegra.c clocksource/drivers/tegra: Set up maximum-ticks limit properly 2019-06-25 19:49:18 +02:00
timer-ti-32k.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 341 2019-06-05 17:37:07 +02:00
timer-ti-dm.c clocksource/drivers/timer-ti-dm: Change to new style declaration 2019-05-24 15:51:30 +02:00
timer-u300.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
timer-versatile.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
timer-vf-pit.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
timer-vt8500.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
timer-zevio.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00