linux/drivers/clocksource
Benjamin Gaignard 4744daa10d clocksource/drivers/stm32: Compute a prescaler value with a targeted rate
The prescaler value is arbitrarily set to 1024 without any regard to the
timer frequency. For 32-bit timers, there is no need to set a prescaler
value as they wrap in an acceptable interval and give the opportunity to
have precise timers on this platform. However, for 16-bit timers a prescaler
value is needed if we don't want to wrap too often per second which is
inefficient and adds more and more error margin. With a targeted clock
of 10MHz, the 16 bits are precise enough whatever the timer frequency is
as we will compute the prescaler.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-15-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:25 +01:00
..
acpi_pm.c clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
arc_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
arm_arch_timer.c First batch of KVM changes for 4.15 2017-11-16 13:00:24 -08:00
arm_global_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
armv7m_systick.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
asm9260_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
bcm2835_timer.c locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() 2017-10-25 11:01:08 +02:00
bcm_kona_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
cadence_ttc_timer.c Merge branch 'timers/urgent' into timers/core 2017-06-21 09:07:52 +02:00
clksrc_st_lpc.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
clksrc-dbx500-prcmu.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
clps711x-timer.c clocksource/drivers: Rename CLKSRC_OF to TIMER_OF 2017-06-14 12:01:03 +02:00
cs5535-clockevt.c clockevents/drivers/cs5535: Improve resilience to spurious interrupts 2017-10-20 13:41:52 +02:00
dummy_timer.c cpu/hotplug: Cleanup state names 2016-12-25 10:47:44 +01:00
dw_apb_timer_of.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
dw_apb_timer.c Merge branch 'clockevents/4.12' of https://git.linaro.org/people/daniel.lezcano/linux into timers/core 2017-04-17 10:55:14 +02:00
em_sti.c clocksource/drivers/em_sti: Fix error return codes in em_sti_probe() 2017-08-10 14:48:18 +02:00
exynos_mct.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
fsl_ftm_timer.c clocksource/drivers/fsl_ftm_timer: Unmap region obtained by of_iomap 2017-06-27 11:25:39 +02:00
h8300_timer8.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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
i8253.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
jcore-pit.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
Kconfig clocksource/drivers/stm32: Convert the driver to timer_of primitives 2018-01-08 17:57:25 +01:00
Makefile clocksource/drivers/spreadtrum: Add timer driver for the Spreadtrum SC9860 platform 2018-01-08 17:57:24 +01:00
meson6_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
metag_generic.c clockevents/drivers/metag: Set ->min_delta_ticks and ->max_delta_ticks 2017-04-14 13:11:13 -07:00
mips-gic-timer.c clocksource/drivers/mips-gic-timer: Add fastpath for local timer updates 2017-10-19 23:51:31 +02:00
mmio.c clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
mps2-timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
mtk_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
mxs_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
nomadik-mtu.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
numachip.c x86/numachip: Add const and __initconst to numachip2_clockevent 2017-09-25 09:36:15 +02:00
owl-timer.c clocksource/drivers/owl: Add the S700 timer 2018-01-08 17:57:23 +01:00
pxa_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
qcom-timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
renesas-ostm.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
rockchip_timer.c clocksource/drivers/rockchip: pr_err() strings should end with newlines 2017-10-19 23:49:02 +02:00
samsung_pwm_timer.c clocksource/drivers: Rename CLKSRC_OF to TIMER_OF 2017-06-14 12:01:03 +02:00
scx200_hrt.c clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
sh_cmt.c clocksource/drivers/sh_cmt: Use of_device_get_match_data() helper 2017-10-19 23:48:59 +02:00
sh_mtu2.c clocksource/drivers/sh_mtu2: Fix multiple shutdown call issue 2015-10-28 15:22:56 +01:00
sh_tmu.c clocksource: sh_tmu: Compute rate before registration again 2017-03-23 12:14:01 -07:00
sun4i_timer.c clocksource/drivers/sun4i: Switch to the timer-of common init 2017-06-26 18:32:04 +02:00
tango_xtal.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tcb_clksrc.c clocksource/drivers/tcb_clksrc: Fix clock speed message 2018-01-08 17:57:23 +01:00
tegra20_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
time-armada-370-xp.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
time-efm32.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
time-lpc32xx.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
time-orion.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
time-pistachio.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-atlas7.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-atmel-pit.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-atmel-st.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-digicolor.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-fttmr010.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
timer-imx-gpt.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-imx-tpm.c clocksource/drivers/imx-tpm: Add imx tpm timer support 2017-08-29 11:07:56 +02:00
timer-integrator-ap.c clocksource/integrator: Fix section mismatch warning 2017-09-18 09:37:33 +02:00
timer-keystone.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +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 clocksource/drivers/timer-of: Don't request the resource by name 2018-01-08 17:57:24 +01:00
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-oxnas-rps.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-prima2.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-probe.c clocksource: Convert to using %pOF instead of full_name 2017-08-31 15:56:17 +02:00
timer-sp804.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +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-sprd.c clocksource/drivers/spreadtrum: Add timer driver for the Spreadtrum SC9860 platform 2018-01-08 17:57:24 +01:00
timer-stm32.c clocksource/drivers/stm32: Compute a prescaler value with a targeted rate 2018-01-08 17:57:25 +01:00
timer-sun5i.c Merge branch 'timers/urgent' into timers/core 2017-06-21 09:07:52 +02:00
timer-ti-32k.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
timer-u300.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
versatile.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
vf_pit_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
vt8500_timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00
zevio-timer.c clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE 2017-06-14 11:58:45 +02:00