Commit Graph

17 Commits

Author SHA1 Message Date
Marc Zyngier 2f0778afac ARM: 7205/2: sched_clock: allow sched_clock to be selected at runtime
sched_clock() is yet another blocker on the road to the single
image. This patch implements an idea by Russell King:

http://www.spinics.net/lists/linux-omap/msg49561.html

Instead of asking the platform to implement both sched_clock()
itself and the rollover callback, simply register a read()
function, and let the ARM code care about sched_clock() itself,
the conversion to ns and the rollover. sched_clock() uses
this read() function as an indirection to the platform code.
If the platform doesn't provide a read(), the code falls back
to the jiffy counter (just like the default sched_clock).

This allow some simplifications and possibly some footprint gain
when multiple platforms are compiled in. Among the drawbacks,
the removal of the *_fixed_sched_clock optimization which could
negatively impact some platforms (sa1100, tegra, versatile
and omap).

Tested on 11MPCore, OMAP4 and Tegra.

Cc: Imre Kaloz <kaloz@openwrt.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Colin Cross <ccross@android.com>
Cc: Erik Gilling <konkers@android.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Alessandro Rubini <rubini@unipv.it>
Cc: STEricsson <STEricsson_nomadik_linux@list.st.com>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Tested-by: Jamie Iles <jamie@jamieiles.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Krzysztof Halasa <khc@pm.waw.pl>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-18 23:00:26 +00:00
Jonas Aaberg 05387a9fbf ARM: plat-nomadik: timer: Export reset functions
We make the reset function from the driver public, then
we also move of all register defines from the public header
file into driver, where they belong.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-09-22 15:44:17 +02:00
Jonas Aaberg 2f73a06843 ARM: plat-nomadik: timer: Add support for periodic timers
This adds support for a periodic mode in the MTU (Nomadik)
timer clockevent driver. It also include changes needed for
deeper powerstates where MTU block gets powered off.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-09-22 15:44:10 +02:00
Mattias Wallin cba13830d3 ARM: plat-nomadik: MTU sched_clock as an option
This patch makes it possible to configure away the sched_clock
part of the MTU timer.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Signed-off-by: Jonas Aberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-09-22 15:42:33 +02:00
Russell King bfe45e0be8 clocksource: convert ARM 32-bit down counting clocksources
Convert SP804, MXC, Nomadik and Orion 32-bit down-counting clocksources
to generic mmio clocksource infrastructure.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Alessandro Rubini <rubini@unipv.it>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-05-23 18:04:51 +01:00
Russell King ec05aa1399 ARM: nomadik: convert sched_clock() to use new infrastructure
Convert nomadik platforms to use the new sched_clock() infrastructure
for extending 32bit counters to full 64-bit nanoseconds.

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-22 22:44:48 +00:00
Russell King 5e06b6492e ARM: ensure all sched_clock() implementations are notrace marked
ftrace requires sched_clock() to be notrace.  Ensure that all
implementations are so marked.  Also make sure that they include
linux/sched.h

Also ensure OMAP clocksource read functions are marked notrace as
they're used for sched_clock() too.

Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Tested-by: Eric Miao <eric.y.miao@gmail.com>
Tested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-22 22:44:42 +00:00
Russell King 8492fd2898 ARM: nomadik: update clock source registration
In d7e81c2 (clocksource: Add clocksource_register_hz/khz interface) new
interfaces were added which simplify (and optimize) the selection of the
divisor shift/mult constants.  Switch over to using this new interface.

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-22 22:44:39 +00:00
Linus Walleij 8fbb97a2bc ARM: 6488/1: nomadik: prevent sched_clock() wraparound
The current implementation of sched_clock() for the Nomadik
family is based on the clock source that will wrap around without
any compensation. Currently on the Ux500 after 1030 seconds.

Utilize cnt32_to_63 to expand the sched_clock() counter to 63
bits and introduce a keepwarm() timer to assure that sched clock
and this cnt32_to_63 is called atleast once every half period.

When I print out the actual wrap-around time, and using
a year (3600*24*365 seconds) as minumum wrap limit I get an
actual wrap-around of:
sched_clock: using 55 bits @ 8333125 Hz wrap in 416 days

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-11-21 22:05:57 +00:00
Linus Walleij a0719f52d9 ARM: 6376/1: plat-nomadik: MTU: Change prescaler limit and comment updates
The prescaler 16 is now used only when the timer runs at 32 MHz
or more. Some comment updates as well.

Acked-by: Alessandro Rubini <rubini@unipv.it>
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-17 10:16:48 +01:00
Linus Walleij 99f76891a3 ARM: 6375/1: plat-nomadik: MTU timer trivial bug fix
timer0 to 3 are all on mtu block 0, so don't calculate the clock event
rate based upon mtu block 1's clock speed.

Acked-by: Alessandro Rubini <rubini@unipv.it>
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-17 10:16:47 +01:00
Linus Walleij 2917947a67 ARM: 6153/1: nomadik MTU to use dynamic shift and mult assignment
This removes the hard-coded shift values for the MTU timer, since
the different platforms using this has very different running
frequencies doing this dynamically is a better idea. Also take
this opportunity to make a more through shutdown of the MTU
clockevent when requested.

Acked-by: Alessandro Rubini <rubini@unipv.it>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-06-16 22:29:31 +01:00
Linus Walleij ba327b1e52 ARM: 6145/1: ux500 MTU clockrate correction
This adjusts the clockrate for the MTU timer. On the different
UX500 variants this rate is different. The platform can also have
been set up at hardware initialization, bootloader or early init
for different clock speeds. To have the clock framework available
early so the timers can use them, the clock initialization for
Nomadik and ux500 is moved to IRQ init time. A custom per-clock
callback is added to handle special cases like this.

This solves a user-visible bug: without this patch the current
UX500 platforms will not be synchronized to wall-clock time and
the platform will drift in time.

Acked-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-05-27 10:36:08 +01:00
Linus Walleij 2a847513cd ARM: 6107/1: plat-nomadik: use the MTU clocksrc for sched_clock
This provides some serious scheduling for the Nomadik family by
introducing a sched_clock() using the MTU clock source in the
same manner as e.g. OMAP or U300. This type of solutions has been
discussed at no end in the past, however we need this resolution
for making measurements and using HRTimers.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-05-13 12:22:42 +01:00
Alessandro Rubini b102c01fae ARM: 5978/1: plat-nomadik: use one-shot clock events
This is a complete rewrite of the MTU driver, using one-shot
for events and a free-running timer for stamping. It allows
CONFIG_NO_HZ and CONFIG_HIGH_RES_TIMERS to work on Nomadik and Ux500.

Signed-off-by: Alessandro Rubini <rubini@unipv.it>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Andrea Gallo <andrea.gallo@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-03-19 18:31:51 +00:00
Uwe Kleine-König a602f0f2f0 arm/{pxa,sa1100,nomadik}: Don't disable irqs in set_next_event and set_mode
These functions are called with irqs already off.  This commit removes
the calls to raw_local_irq_save and raw_local_irq_restore on platforms
that don't have to use a shared interrupt for their timekeeping.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2010-01-22 17:04:52 +01:00
Srinidhi Kasagar 59b559d7a3 ARM: 5786/1: Introduce plat-nomadik, MTU code re-organization
Introduce the plat-nomadik folder for ST-Ericsson
machines including the existing nomadik 8815 architecture.
This also moves the existing MTU (MultiTimerUnit)
of nomadik 8815 to the proposed plat-nomadik and adds
HAS_MTU. The patch has been re-based to 2.6.32-rc6

Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Alessandro Rubini <rubini@unipv.it>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-11-28 10:22:51 +00:00