The System Timer peripheral provides four 32-bit timer channels and a
single 64-bit free running counter. Each channel has an output compare
register, which is compared against the 32 least significant bits of the
free running counter values, and generates an interrupt.
Timer 3 is used as the Linux timer.
The BCM2835 also contains an SP804-based timer module. However, it
apparently has significant differences from the standard SP804 IP block,
and Broadcom's documentation recommends using the system timer instead.
This patch was extracted from git://github.com/lp0/linux.git branch
rpi-split as of 2012/09/08, and modified as follows:
* s/bcm2708/bcm2835/.
* Modified device tree vendor prefix.
* Moved to drivers/clocksource/. This looks like the desired location for
such code now.
* Added DT binding docs.
* Moved struct sys_timer bcm2835_timer into time.c to encapsulate it more.
* Simplified bcm2835_time_init() to find one matching node and operate on
it, rather than looping over all matching nodes. This seems more
consistent with other clocksource code.
* Simplified bcm2835_time_init() using of_iomap().
* Renamed struct bcm2835_timer.index to match_mask to better represent its
purpose.
* s/printk(PR_INFO/pr_info(/
Signed-off-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Dom Cobley <popcornmix@gmail.com>
Signed-off-by: Dom Cobley <dc4@broadcom.com>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This patch adds support for the ARM generic timers with A64 instructions
for accessing the timer registers. It uses the physical counter as the
clock source and the virtual counter as sched_clock.
The timer frequency can be specified via DT or read from the CNTFRQ_EL0
register. The physical counter is also accessible from user space
allowing fast gettimeofday() implementation.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Modify the SH MTU2 clock event device driver to support runtime PM at
a basic level (i.e. device clocks can be disabled and enabled, but
domain power must be on, because the device has to be marked as
"irq safe").
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Modify the SH CMT clock source/clock event device driver to support
runtime PM at a basic level (i.e. device clocks can be disabled and
enabled, but domain power must be on, because the devices have to
be marked as "irq safe").
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Modify the SH TMU clock source/clock event device driver to support
runtime PM at a basic level (i.e. device clocks can be disabled and
enabled, but domain power must be on, because the devices have to
be marked as "irq safe").
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
The syscore device PM flag is used to mark the devices (belonging to
a PM domain) that should never be turned off, except for the system
core (syscore) suspend/hibernation and resume stages. That flag is
stored in the device's struct pm_subsys_data object whose address is
available from struct device. However, in some situations it may be
convenient to set that flag before the device is added to a PM
domain, so it is better to move it directly to the "power" member of
struct device. Then, it can be checked by the routines in
drivers/base/power/runtime.c and drivers/base/power/main.c, which is
more straightforward.
This also reduces the number of dev_gpd_data() invocations in the
generic PM domains framework, so the overhead related to the syscore
flag is slightly smaller.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
The always_on device flag is used to mark the devices (belonging to
a PM domain) that should never be turned off, except for the system
core (syscore) suspend/hibernation and resume stages. Change name
of that flag to "syscore" to better reflect its purpose.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Introduce suspend/resume routines for SH MTU2 clock event devices
such that if those devices belong to a PM domain, the generic PM
domains framework will be notified that the given domain may be
turned off (during system suspend) or that it has to be turned on
(during system resume).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Introduce suspend/resume routines for SH CMT clock event devices and
modify the suspend/resume routines for SH CMT clock sources such that
if those devices belong to a PM domain, the generic PM domains
framework will be notified that the given domain may be turned off
(during system suspend) or that it has to be turned on (during system
resume).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Introduce suspend/resume routines for SH TMU clock source and
clock event device such that if those devices belong to a PM domain,
the generic PM domains framework will be notified that the given
domain may be turned off (during system suspend) or that it has to
be turned on (during system resume).
This change allows the A4R domain on SH7372 to be turned off during
system suspend (tested on the Mackerel board) if the TMU clock source
and/or clock event device is in use.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
Make a common device tree glue for clocksource/dw_apb_timer.
Move mach-picoxcell/time.c to be a generic device tree application
of the dw_apb_timer.
Configure mach-picoxcell to use the dw_apb_timer_of device tree
implementation in drivers/clocksource.
Signed-off-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Timer 0 is used as free-running clocksource, while timer 1 is used as
clock_event_device.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Lior Amsalem <alior@marvell.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Yehuda Yitschak <yehuday@marvell.com>
Tested-by: Lior Amsalem <alior@marvell.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: John Stultz <johnstul@us.ibm.com>
This switches over to the now exported clockevents_config() and
clockevents_config_and_register() helpers. This knocks off a
long-standing TMU TODO item.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This platform has been obsoleted and was only available inside of
ST-Ericsson, no users of this code are left in the world. This
deletes the core U5500 support entirely in the same manner as the
obsoleted U8500 silicon was previously deleted.
The cpu_is_u5500() macros that can read out the CPU ID is left
until the next kernel cycle, this makes it possible to merge
deletion of dependent drivers without breakage.
This also has the upside of removing the mailbox driver which was
our only driver that was outside the drivers/* hiearchy, now the
machine directory only handles machines and nothing else.
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: Jonas Aberg <jonas.aberg@stericsson.com>
Cc: Per Forlin <per.forlin@stericsson.com>
Cc: Ulf Hansson <ulf.hansson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This reverts commit b519508298.
The reason for this revert is that making the frequency verification
preemptible and interruptible is not working reliably. Michaels
machine failed to use PM-timer with the message:
PM-Timer running at invalid rate: 113% of normal - aborting.
That's not a surprise as the frequency verification does rely on
interrupts being disabled. With a async scheduled thread there is no
guarantee to achieve the same result. Also some driver might fiddle
with the CTC channel 2 during the verification period, which makes the
result even more random and unpredictable.
This can be solved by using the same mechanism as we use in the
deferred TSC validation code, but that only will work if we verified a
working HPET _BEFORE_ trying to do the PM-Timer lazy validation.
So for now reverting is the safe option.
Bisected-by: Michael Witten <mfwitten@gmail.com>
Cc: Arjan van de Ven <arjanvandeven@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <alpine.LFD.2.02.1204112303270.2542@ionos>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Make the MTU2 clocksource driver mark its device as "always on"
using pm_genpd_dev_always_on() to protect it from surprise power
removals.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Simon Horman <horms@verge.net.au>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: stable@vger.kernel.org
Make the CMT clocksource driver mark its device as "always on"
using pm_genpd_dev_always_on() to protect it from surprise power
removals.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Simon Horman <horms@verge.net.au>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: stable@vger.kernel.org
Make the TMU clocksource driver mark its device as "always on"
using pm_genpd_dev_always_on() to protect it from surprise power
removals and make sh7372_add_standard_devices() add TMU devices on
sh7372 to the A4R power domain so that their "always on" flags
are taken into account as appropriate.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Simon Horman <horms@verge.net.au>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: stable@vger.kernel.org
Shared timer IRQs are not a good solution, however the Geode platform has
no APIC, IRQs are a scarce resource and there is no technical reason to
forbid it rightaway. Increased latencies and overhead due to sharing are
still better than a driver refusing to load.
Signed-off-by: Jens Rottmann <JRottmann@LiPPERTEmbedded.de>
Acked-by: Andres Salomon <dilinger@queued.net>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
On SMP-capable kernels (e.g. generic distro kernel) the cs5535-clockevt
driver loads but is not actually used.
Setting cpumask to cpu_all_mask works for UP-only kernels, but if compiled
for SMP - though still running on the same UP hardware -
kernel/time/tick-common.c:tick_check_new_device() reads this as
"non-cpu-local" and silently ignores the device.
If we leave cpumask unset clockevents_register_device() will initialize it
and the cs5535-clockevt driver will be used no matter how the kernel was
compiled. Should anyone ever manage to stick a CS553x in an SMP system
(is this even possible?) then a warning will be printed. This is fine as
the cs5535-clockevt driver was never written/tested for SMP.
If bisecting led you here this patch may have exposed a pre-existing MFGPT
problem. Configure for UP-only and re-check.
Signed-off-by: Jens Rottmann <JRottmann@LiPPERTEmbedded.de>
Acked-by: Andres Salomon <dilinger@queued.net>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Some SoC have a 32 bit variant of Timer Counter Blocks. We do not
need the chaining of two 16 bit counters anymore for them.
The SoC nature is deduced from the device tree "compatible" string.
For non-device-tree configurations, backward compatibility is maintained
by using the default 16 bit counter configuration.
This patch addresses both the atmel_tclib and its user: tcb_clksrc
clocksource.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
This commit:
12d6d41276de: clocksource: scx200_hrt: Convert scx200 to use clocksource_register_hz
Breaks the build on x86-32:
drivers/clocksource/scx200_hrt.c: In function ‘init_hrt_clocksource’:
drivers/clocksource/scx200_hrt.c:95:0: error: unterminated argument list invoking macro "pr_info"
drivers/clocksource/scx200_hrt.c:84:2: error: ‘pr_info’ undeclared (first use in this function)
It could not possibly have been build tested, because it had this mismerge:
pr_info("enabling scx200 high-res timer (%s MHz +%d ppm)\n",
printk(KERN_INFO "enabling scx200 high-res timer (%s MHz +%d ppm)\n",
mhz27 ? "27":"1", ppm);
Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/n/tip-jceb26fns5w7tv8edlivhxpa@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The ACPI clocksource takes quite some time to initialize,
and this increases the boot time of the kernel for a
double digit percentage. This while almost all modern
systems will be using the HPET already anyway.
This patch turns the clocksource loading into an asynchronous
operation; which means it won't hold up the boot while
still becoming available normally.
To make this work well, an udelay() had to be turned into an
usleep_range() so that on UP systems, we yield the CPU to
regular boot tasks instead of spinning.
CC: John Stultz <johnstul@us.ibm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Len Brown <lenb@kernel.org>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Converts the scx200 clocksource to using clocksource_register_hz.
CC: Jim Cromie <jim.cromie@gmail.com>
Tested-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Switch from printk to using pr_<level>.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
[added commit msg & tweaked subject -jstultz]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Add missing iounmap in error handling code, in a case where the function
already preforms iounmap on some other execution path.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e;
statement S,S1;
int ret;
@@
e = \(ioremap\|ioremap_nocache\)(...)
... when != iounmap(e)
if (<+...e...+>) S
... when any
when != iounmap(e)
*if (...)
{ ... when != iounmap(e)
return ...; }
... when any
iounmap(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
[fixed up subject -jstultz]
Signed-off-by: John Stultz <john.stultz@linaro.org>
commit 2f0778afac adding
runtime-selectable sched_clock() forgot to patch this
driver down in drivers/clocksource, this patch fixes
the problem.
Reported-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The i8253 clockevent & clocksource driver uses PIT_LATCH
except for two cases where it uses LATCH:
1)
/* VIA686a test code... reset the latch if count > max + 1 */
if (count > LATCH) {
LATCH is based on CLOCK_TICK_RATE which is defined as
PIT_TICK_RATE on x86 so this should just be the later.
2)
...
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
/* binary, mode 2, LSB/MSB, ch 0 */
outb_p(0x34, PIT_MODE);
outb_p(LATCH & 0xff , PIT_CH0); /* LSB */
outb_p(LATCH >> 8 , PIT_CH0); /* MSB */
...
MIPS and ARM are the only other arches that use this driver. In
the MIPS case CLOCK_TICK_RATE is defined as the same value as
PIT_TICK_RATE. For ARM, the only machine that uses it is
Footbridge which has a totally bogus CLOCK_TICK_RATE according
to the comments. Furthermore, the clockevent_i8253_init()
initializes the clockevent with PIT_TIC_RATE, so there's
no reason to use the generic LATCH.
This is part of work to remove and depecrate the global
CLOCK_TICK_RATE symbol.
Signed-off-by: Deepak Saxena <dsaxena@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The acpi_pm clocksource driver uses CLOCK_TICK_RATE which is
defined as PIT_TICK_RATE on x86. This patch cleans it up to
just use the later so that CLOCK_TICK_RATE can be depecrated.
Signed-off-by: Deepak Saxena <dsaxena@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
A pending cleanup will mean that module.h won't be implicitly
everywhere anymore. Make sure the modular drivers in clocksource
are actually calling out for <module.h> explicitly in advance.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The clocksource name should be const for correctness.
Cc: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Based on a patch from Arnd Bergmann this fixes up the build
problem of assigning a non-existing global when the ux500 PRCMU
timer is not linked in by passing its base address to the init
function. We also add a missing <linux/errno.h> inclusion and
staticize the dummy function.
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch adds the DBX500 PRCMU Timer driver as a clocksource
and as sched_clock.
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add code to the CMT driver to wait for CMCNT V2. This to let
the register value settle before starting the timer channel.
Makes the driver more robust.
Needed for CMT2 on sh7372 and certain CMT channels on sh73a0.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
arm, mips and x86 implement i8253 based clockevents. All the same code
copied. Create a common implementation in drivers/clocksource/i8253.c.
About time to rename drivers/clocksource/ to something else.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20110609130621.921710458@linutronix.de
The APB timers are an IP block from Synopsys (DesignWare APB timers)
and are also found in other systems including ARM SoC's. This patch
adds functions for creating clock_event_devices and clocksources from
APB timers but does not do the resource allocation. This is handled
in a higher layer to allow the timers to be created from multiple
methods such as platform_devices.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Now that all extra ifdeffed implementations are gone, depend the lock
export on PCSPKR_PLATFORM
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@arm.linux.org.uk>
Move them to drivers/clocksource/i8253.c and remove the
implementations in arch/
[ tglx: Avoid the extra file in lib - folded arch patches in. The
export will become conditional in a later step ]
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Link: http://lkml.kernel.org/r/20110601180610.221426078@duck.linux-mips.net
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This reverts commit 1b842e91fe.
There is a fundamental ordering race between the early and late probe
paths and the runtime PM tie-in that results in __pm_runtime_resume()
attempting to take a lock that hasn't been initialized yet (which by
proxy also suggests that pm_runtime_init() hasn't yet been run on the
device either, making the entire thing unsafe) -- resulting in instant
death on SMP or on UP with spinlock debugging enabled:
sh_tmu.0: used for clock events
sh_tmu.0: used for periodic clock events
BUG: spinlock trylock failure on UP on CPU#0, swapper/0
lock: 804db198, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
...
Revert it for now until the ordering issues can be resolved, or we can get
some more help from the runtime PM framework to make this possible.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Simon Arlott