Instead of directly calling RISC-V timer interrupt handler from
RISC-V local interrupt conntroller driver, this patch implements
RISC-V timer interrupt as a per-CPU interrupt using per-CPU APIs
of Linux IRQ subsystem.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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
The MIPS GIC timer is well suited for use as sched_clock, so register it
as such.
Whilst the existing gic_read_count() function matches the prototype
needed by sched_clock_register() already, we split it into 2 functions
in order to remove the need to evaluate the mips_cm_is64 condition
within each call since sched_clock should be as fast as possible.
Note the sched clock framework needs the clock source being stable in
order to rely on it. So we register the MIPS GIC timer as schedule clocks
only if it's, if either the system doesn't have CPU-frequency enabled or
the CPU frequency is changed by means of the CPC core clock divider
available on the platforms with CM3 or newer.
Signed-off-by: Paul Burton <paulburton@kernel.org>
Co-developed-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
[Sergey.Semin@baikalelectronics.ru: Register sched-clock if CM3 or !CPU-freq]
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
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/20200521204818.25436-8-Sergey.Semin@baikalelectronics.ru
Commit 1002148899 ("clocksource: dw_apb_timer_of: use
clocksource_of_init") replaced a publicly available driver
initialization method with one called by the timer_probe() method
available after CLKSRC_OF. In current implementation it traverses
all the timers available in the system and calls their initialization
methods if corresponding devices were either in dtb or in acpi. But
if before the commit any number of available timers would be installed
as clockevent and clocksource devices, after that there would be at most
two. The rest are just ignored since default case branch doesn't do
anything. I don't see a reason of such behaviour, neither the commit
message explains it. Moreover this might be wrong if on some platforms
these timers might be used for different purpose, as virtually CPU-local
clockevent timers and as an independent broadcast timer. So in order
to keep the compatibility with the platforms where the order of the
timers detection has some meaning, lets add the secondly discovered
timer to be of clocksource/sched_clock type, while the very first and
the others would provide the clockevents service.
Fixes: 1002148899 ("clocksource: dw_apb_timer_of: use clocksource_of_init")
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/20200521204818.25436-7-Sergey.Semin@baikalelectronics.ru
Currently the DW APB Timer driver binds each clockevent timers to a
particular CPU. This isn't good for multiple reasons. First of all seeing
the device is placed on APB bus (which makes it accessible from any CPU
core), accessible over MMIO and having the DYNIRQ flag set we can be sure
that manually binding the timer to any CPU just isn't correct. By doing
so we just set an extra limitation on device usage. This also doesn't
reflect the device actual capability, since by setting the IRQ affinity
we can make it virtually local to any CPU. Secondly imagine if you had a
real CPU-local timer with the same rating and the same CPU-affinity.
In this case if DW APB timer was registered first, then due to the
clockevent framework tick-timer selection procedure we'll end up with the
real CPU-local timer being left unselected for clock-events tracking. But
on most of the platforms (MIPS/ARM/etc) such timers are normally embedded
into the CPU core and are accessible with much better performance then
devices placed on APB. For instance in MIPS architectures there is
r4k-timer, which is CPU-local, assigned with the same rating, and normally
its clockevent device is registered after the platform-specific one.
So in order to fix all of these issues let's make the DW APB Timer CPU
affinity being optional and deactivated by passing a negative CPU id,
which will effectively set the DW APB clockevent timer cpumask to
'cpu_possible_mask'.
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/20200521204818.25436-5-Sergey.Semin@baikalelectronics.ru
We can get a warning for dmtimer_clocksource_init() with 'pa' set but
not used. This was used in the earlier revisions of the code but no
longer needed, so let's remove the unused pa and of_translate_address().
Let's also do it for dmtimer_clockevent_init() that has a similar issue.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200519155157.12804-1-tony@atomide.com
We can move the TI dmtimer clockevent and clocksource to live under
drivers/clocksource if we rely only on the clock framework, and handle
the module configuration directly in the clocksource driver based on the
device tree data.
This removes the early dependency with system timers to the interconnect
related code, and we can probe pretty much everything else later on at
the module_init level.
Let's first add a new driver for timer-ti-dm-systimer based on existing
arch/arm/mach-omap2/timer.c. Then let's start moving SoCs to probe with
device tree data while still keeping the old timer.c. And eventually we
can just drop the old timer.c.
Let's take the opportunity to switch to use readl/writel as pointed out
by Daniel Lezcano <daniel.lezcano@linaro.org>. This allows further
clean-up of the timer-ti-dm code the a lot of the shared helpers can
just become static to the non-syster related code.
Note the boards can optionally configure different timer source clocks
if needed with assigned-clocks and assigned-clock-parents.
Cc: linux-kernel@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200507172330.18679-3-tony@atomide.com
We can get a warning for dmtimer_clocksource_init() with 'pa' set but
not used. This was used in the earlier revisions of the code but no
longer needed, so let's remove the unused pa and of_translate_address().
Let's also do it for dmtimer_clockevent_init() that has a similar issue.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200519155157.12804-1-tony@atomide.com
We can move the TI dmtimer clockevent and clocksource to live under
drivers/clocksource if we rely only on the clock framework, and handle
the module configuration directly in the clocksource driver based on the
device tree data.
This removes the early dependency with system timers to the interconnect
related code, and we can probe pretty much everything else later on at
the module_init level.
Let's first add a new driver for timer-ti-dm-systimer based on existing
arch/arm/mach-omap2/timer.c. Then let's start moving SoCs to probe with
device tree data while still keeping the old timer.c. And eventually we
can just drop the old timer.c.
Let's take the opportunity to switch to use readl/writel as pointed out
by Daniel Lezcano <daniel.lezcano@linaro.org>. This allows further
clean-up of the timer-ti-dm code the a lot of the shared helpers can
just become static to the non-syster related code.
Note the boards can optionally configure different timer source clocks
if needed with assigned-clocks and assigned-clock-parents.
Cc: linux-kernel@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200507172330.18679-3-tony@atomide.com
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
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: 625022a5f1 ("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
pr_xxx() functions usually have '\n' at the end of the logging message.
Here, this '\n' is added via the 'pr_fmt' macro.
In order to be more consistent with other files, use a more standard
convention and put these '\n' back in the messages themselves and remove it
from the pr_fmt macro.
While at it, remove a useless message in case of 'kzalloc' failure,
especially with a __GFP_NOFAIL flag.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200409092543.14727-1-christophe.jaillet@wanadoo.fr
Pull arm64 updates from Catalin Marinas:
"The bulk is in-kernel pointer authentication, activity monitors and
lots of asm symbol annotations. I also queued the sys_mremap() patch
commenting the asymmetry in the address untagging.
Summary:
- In-kernel Pointer Authentication support (previously only offered
to user space).
- ARM Activity Monitors (AMU) extension support allowing better CPU
utilisation numbers for the scheduler (frequency invariance).
- Memory hot-remove support for arm64.
- Lots of asm annotations (SYM_*) in preparation for the in-kernel
Branch Target Identification (BTI) support.
- arm64 perf updates: ARMv8.5-PMU 64-bit counters, refactoring the
PMU init callbacks, support for new DT compatibles.
- IPv6 header checksum optimisation.
- Fixes: SDEI (software delegated exception interface) double-lock on
hibernate with shared events.
- Minor clean-ups and refactoring: cpu_ops accessor,
cpu_do_switch_mm() converted to C, cpufeature finalisation helper.
- sys_mremap() comment explaining the asymmetric address untagging
behaviour"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (81 commits)
mm/mremap: Add comment explaining the untagging behaviour of mremap()
arm64: head: Convert install_el2_stub to SYM_INNER_LABEL
arm64: Introduce get_cpu_ops() helper function
arm64: Rename cpu_read_ops() to init_cpu_ops()
arm64: Declare ACPI parking protocol CPU operation if needed
arm64: move kimage_vaddr to .rodata
arm64: use mov_q instead of literal ldr
arm64: Kconfig: verify binutils support for ARM64_PTR_AUTH
lkdtm: arm64: test kernel pointer authentication
arm64: compile the kernel with ptrauth return address signing
kconfig: Add support for 'as-option'
arm64: suspend: restore the kernel ptrauth keys
arm64: __show_regs: strip PAC from lr in printk
arm64: unwind: strip PAC from kernel addresses
arm64: mask PAC bits of __builtin_return_address
arm64: initialize ptrauth keys for kernel booting task
arm64: initialize and switch ptrauth kernel keys
arm64: enable ptrauth earlier
arm64: cpufeature: handle conflicts based on capability
arm64: cpufeature: Move cpu capability helpers inside C file
...
Pull timekeeping and timer updates from Thomas Gleixner:
"Core:
- Consolidation of the vDSO build infrastructure to address the
difficulties of cross-builds for ARM64 compat vDSO libraries by
restricting the exposure of header content to the vDSO build.
This is achieved by splitting out header content into separate
headers. which contain only the minimaly required information which
is necessary to build the vDSO. These new headers are included from
the kernel headers and the vDSO specific files.
- Enhancements to the generic vDSO library allowing more fine grained
control over the compiled in code, further reducing architecture
specific storage and preparing for adopting the generic library by
PPC.
- Cleanup and consolidation of the exit related code in posix CPU
timers.
- Small cleanups and enhancements here and there
Drivers:
- The obligatory new drivers: Ingenic JZ47xx and X1000 TCU support
- Correct the clock rate of PIT64b global clock
- setup_irq() cleanup
- Preparation for PWM and suspend support for the TI DM timer
- Expand the fttmr010 driver to support ast2600 systems
- The usual small fixes, enhancements and cleanups all over the
place"
* tag 'timers-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits)
Revert "clocksource/drivers/timer-probe: Avoid creating dead devices"
vdso: Fix clocksource.h macro detection
um: Fix header inclusion
arm64: vdso32: Enable Clang Compilation
lib/vdso: Enable common headers
arm: vdso: Enable arm to use common headers
x86/vdso: Enable x86 to use common headers
mips: vdso: Enable mips to use common headers
arm64: vdso32: Include common headers in the vdso library
arm64: vdso: Include common headers in the vdso library
arm64: Introduce asm/vdso/processor.h
arm64: vdso32: Code clean up
linux/elfnote.h: Replace elf.h with UAPI equivalent
scripts: Fix the inclusion order in modpost
common: Introduce processor.h
linux/ktime.h: Extract common header for vDSO
linux/jiffies.h: Extract common header for vDSO
linux/time64.h: Extract common header for vDSO
linux/time32.h: Extract common header for vDSO
linux/time.h: Extract common header for vDSO
...
Pull clockevent/clocksource updates from Daniel Lezcano:
- Avoid creating dead devices by flagging the driver with OF_POPULATED
in order to prevent the platform to create another device (Saravana Kannan)
- Remove unused includes from imx family drivers (Anson Huang)
- timer-dm-ti rework to prepare for pwm and suspend support (Lokesh Vutla)
- Fix the rate for the global clock on the pit64b (Claudiu Beznea)
- Fix timer-cs5535 by requesting an irq with non-NULL dev_id (Afzal Mohammed)
- Replace setup_irq() by request_irq() (Afzal Mohammed)
- Add support for the TCU of X1000 (Zhou Yanjie)
- Drop the bogus omap_dm_timer_of_set_source() function (Suman Anna)
- Do not update the counter when updating the period in order to
prevent a disruption when the pwm is used (Lokesh Vutla)
- Improve owl_timer_init() failure messages (Matheus Castello)
- Add driver for the Ingenic JZ47xx OST (Maarten ter Huurne)
- Pass the interrupt and the shutdown callbacks in the init function
for ast2600 support (Joel Stanley)
- Add the ast2600 compatible string for the fttmr010 (Joel Stanley)
Timer initialization is done during early boot way before the driver
core starts processing devices and drivers. Timers initialized during
this early boot period don't really need or use a struct device.
However, for timers represented as device tree nodes, the struct devices
are still created and sit around unused and wasting memory. This change
avoid this by marking the device tree nodes as "populated" if the
corresponding timer is successfully initialized.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200111052125.238212-1-saravanak@google.com
dm timer ops set_load() api allows to configure the load value and to
set the auto reload feature. But auto reload feature is independent of
load value and should be part of configuring pwm. This way pwm can be
disabled by disabling auto reload feature using set_pwm() so that the
current pwm cycle will be completed. Else pwm disabling causes the
cycle to be stopped abruptly.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200305082715.15861-7-lokeshvutla@ti.com
Write to trigger register(OMAP_TIMER_TRIGGER_REG) will load the value
in Load register(OMAP_TIMER_LOAD_REG) into Counter register
(OMAP_TIMER_COUNTER_REG).
omap_dm_timer_set_load() writes into trigger register every time load
register is updated. When timer is configured in pwm mode, this causes
disruption in current pwm cycle, which is not expected especially when
pwm is used as PPS signal for synchronized PTP clocks. So do not write
into trigger register on updating the period.
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200305082715.15861-5-lokeshvutla@ti.com
omap_dm_timer_enable() restores the entire context(including counter)
based on 2 conditions:
- If get_context_loss_count is populated and context is lost.
- If get_context_loss_count is not populated update unconditionally.
Case2 has a side effect of updating the counter register even though
context is not lost. When timer is configured in pwm mode, this is
causing undesired behaviour in the pwm period.
Instead of using get_context_loss_count call back, implement cpu_pm
notifier with context save and restore support. And delete the
get_context_loss_count callback all together.
Suggested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
[tony@atomide.com: removed pm_runtime calls from cpuidle calls]
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200316111453.15441-1-lokeshvutla@ti.com
Let's add runtime_suspend and resume functions and atomic enabled
flag. This way we can use these when converting to use cpuidle
for saving and restoring device context.
And we need to maintain the driver state in the driver as documented
in "9. Autosuspend, or automatically-delayed suspends" in the
Documentation/power/runtime_pm.rst document related to using driver
private lock and races with runtime_suspend().
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200305082715.15861-3-lokeshvutla@ti.com
Recently all usages of setup_irq() was replaced by request_irq().
request_irq() does a few sanity checks that were not done in
setup_irq(), if they fail irq registration will fail. One of the check
is to ensure that non-NULL dev_id is passed in the case of shared irq.
Fix it by passing non-NULL dev_id while registering the shared irq.
Fixes: cc2550b421 ("clocksource: Replace setup_irq() by request_irq()")
Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200312064817.19000-1-afzal.mohd.ma@gmail.com
Using an arch timer with a frequency of less than 1MHz can potentially
result in incorrect functionality in systems that assume a reasonable
rate of the arch timer of 1 to 50MHz, described as typical in the
architecture specification.
Therefore, warn if the arch timer rate is below 1MHz, which is
considered atypical and worth emphasizing.
Suggested-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The function omap_dm_timer_of_set_source() was originally added in
commit 31a7448f4f ("ARM: OMAP: dmtimer: Add clock source from DT"),
and is designed to set a clock source from DT using the clocks property
of a timer node. This design choice is okay for clk provider nodes but
otherwise is a bad design as typically the clocks property is used to
specify the functional clocks for a device, and not its parents.
The timer nodes now all define a timer functional clock after the
conversion to ti-sysc and the new clkctrl layout, and this results
in an attempt to set the same functional clock as its parent when a
consumer driver attempts to acquire any of these timers in the
omap_dm_timer_prepare() function. This was masked and worked around
in commit 983a5a43ec ("clocksource: timer-ti-dm: Fix pwm dmtimer
usage of fck reparenting"). Fix all of this by simply dropping the
entire function.
Any DT configuration of clock sources should be achieved using
assigned-clocks and assigned-clock-parents properties provided
by the Common Clock Framework.
Cc: Tony Lindgren <tony@atomide.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Ladislav Michl <ladis@linux-mips.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Suman Anna <s-anna@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200213053504.22638-1-s-anna@ti.com
Write to trigger register(OMAP_TIMER_TRIGGER_REG) will load the value
in Load register(OMAP_TIMER_LOAD_REG) into Counter register
(OMAP_TIMER_COUNTER_REG).
omap_dm_timer_set_load() writes into trigger register every time load
register is updated. When timer is configured in pwm mode, this causes
disruption in current pwm cycle, which is not expected especially when
pwm is used as PPS signal for synchronized PTP clocks. So do not write
into trigger register on updating the period.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200224050753.17784-3-lokeshvutla@ti.com
