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>
These files all make use of one of the EXPORT_SYMBOL variants
or the THIS_MODULE macro. So they will need <linux/export.h>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
There's no need to include linux/sched.h more than once
in arch/arm/plat-iop/time.c
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Convert iop platforms to use the new sched_clock() infrastructure for
extending 32bit counters to full 64-bit nanoseconds.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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>
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.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Ensure that no interrupt is pending before registering the clock
event device, and properly initialize the periodic tick in the
->set_mode callback.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Include sched.h to ensure sched_clock() has the notrace
annotation, and mark any functions it calls as notrace
too.
Include sched.h to ensure sched_clock() has the notrace
annotation, and mark any functions it calls as notrace
too.
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since the infrastructure for determining shift/mult values from a
clock rate and a minimum programmable rate is now in the kernel,
lets remove this custom code.
Cc: Deepak Saxena <dsaxena@plexity.net>
Acked-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This adds a better sched_clock() to the IOP platform,
implemented using its new clocksource support.
Tested on n2100, compile-tested for all plat-iop machines.
[dan.j.williams@intel.com: allow early cp6 access]
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This updates the IOP platform to use the kernel's generic time
framework. With clockevent support in place, this reduces to
selecting GENERIC_TIME and removing the platform's private timer
->offset() operation (iop_gettimeoffset).
Tested on n2100, compile-tested for all plat-iop machines.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This updates the IOP platform to expose the interrupting
timer 0 as a clockevent object. The timer interrupt handler
is changed to call the clockevent ->event_handler() instead
of timer_tick(), and ->set_next_event() and ->set_mode()
operations are added to allow the mode of the timer to be
updated (required for ONESHOT/NOHZ mode).
Timer 0 must now be properly initialised, which requires
a new write_tcr0() function from the mach-specific code.
The mode of timer 0 must be read at the start of ->set_mode(),
which requires a new read_tmr0() function from the mach-
specific code.
Initial setup of timer 0 is also rewritten to be more robust.
Tested on n2100, compile-tested for all plat-iop machines.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This updates the IOP platform to expose the free-running
timer 1 as a clocksource object. This timer is now also
properly initialised, which requires a new write_tcr1()
function from the mach-specific code. Apart from the
explicit initialisation, there is no functional change
in how timer 1 is programmed.
Tested on n2100, compile-tested for all plat-iop machines.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The kernel.h macro DIV_ROUND_CLOSEST performs the computation (x + d/2)/d
but is perhaps more readable.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@haskernel@
@@
#include <linux/kernel.h>
@depends on haskernel@
expression x,__divisor;
@@
- (((x) + ((__divisor) / 2)) / (__divisor))
+ DIV_ROUND_CLOSEST(x,__divisor)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h.
Then, since asm/hardware.h only exists to include asm/arch/hardware.h,
update everything to directly include asm/arch/hardware.h and remove
asm/hardware.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
move update_process_times() out from under xtime_lock.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In order for this driver to be shared across the iop architectures the
iop3xx and iop13xx header files are modified to present a common interface
for the iop_wdt driver.
Details:
* iop13xx supports disabling the timer while iop3xx does not. This requires
a few 'compatibility' definitions in include/asm-arm/hardware/iop3xx.h to
preclude adding #ifdef CONFIG_ARCH_IOP13XX blocks to the driver code.
* The heartbeat interval is derived from the internal bus clock rate, so this
this patch also exports the tick rate to the iop_wdt driver.
Cc: Curt Bruns <curt.e.bruns@intel.com>
Cc: Peter Milne <peter.milne@d-tacq.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add IRQF_IRQPOLL for each timer interrupt.
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a typo which causes a necessary cpwait to be missed on iop3xx, Michael
Brunner <mibru@gmx.de>
Save a register in the assembly routine, rmk
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* architecture specific details are handled in asm/arch/time.h
* ARCH_IOP13XX now selects PLAT_IOP
* as suggested by Lennert use ifdef CONFIG_XSCALE to skip the cp_wait on
XSC3
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This functionality is replaced by cp6_trap
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Untested, but this should fix up the bulk of the totally mechanical
issues, and should make the actual detail fixing easier.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since the iop32x code isn't iop321-specific, and the iop33x code isn't
iop331-specfic, do a s/iop321/iop32x/ and s/iop331/iop33x/, and tidy up
the code to conform to the coding style guidelines somewhat better.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add CP6 enable/disable sequences to the timekeeping code and the IRQ
code. As a result, we can't depend on CP6 access being enabled when
we enter get_irqnr_and_base anymore, so switch the latter over to
using memory-mapped accesses for now.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Merge and rewrite the iop32x/iop33x time code to do lost jiffy
tracking properly, and put the result in plat-iop/time.c.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Marc Zyngier