The dw_apb_timer only "supports PERIODIC mode and their drivers emulate
ONESHOT over that" as described in commit 8fff52fd50 ("clockevents:
Introduce CLOCK_EVT_STATE_ONESHOT_STOPPED state").
Inspired by Viresh, I think the dw_apb_timer also needs to implement
the set_state_oneshot_stopped() which is called by the clkevt core,
when the next event is required at an expiry time of 'KTIME_MAX'. This
normally happens with NO_HZ_{IDLE|FULL} in both LOWRES/HIGHRES modes.
This patch makes the clockevent device to stop on such an event, to
avoid spurious interrupts, as explained by the above commit.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
It seems gcc can automatically inline apbt_writel() for us, but
apbt_real isn't inlined. This patch makes them inline to get a trivial
performance improvement: 4096 rounds of __apbt_read_clocksource() call
spend time on Marvell BG4CT platform:
before the patch 1275240ns on average
after the patch 1263240ns on average
so we get 1% performance improvement.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
It's safe to use the relaxed version. From another side, the relaxed io
accessor macros are available on all architectures now, so we can use
the relaxed versions to get a trivial system performance improvement,
we measured time the following functions spent on Marvell BG4CT:
4096 rounds of __apbt_read_clocksource() call:
before the patch: 1263240ns on average
after the patch: 1250080ns on average
improved by 1%
4096 rounds of apbt_eoi() call:
before the patch: 1290960ns on average
after the patch: 1248240ns on average
4096 rounds of apbt_next_event() call:
before the patch: 3333660ns on average
after the patch: 1322040ns on average
improved by 60%!
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
On Marvell BG4CT platform, we observed the __apbt_read_clocksource()
return wrong value: Let's assume the APBTMR_N_CURRENT_VALUE value is
0xf0000000, we got 0xffffffff0fffffff, but it should be 0xfffffff.
This issue should be common on all 64bit platforms. We fix the issue
by letting aptb_readl() return u32. apbt_writel() is also updated
to write u32 val rather than unsigned long.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Migrate dw_apb driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.
This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Thanks to spatch, plus manual removal of "&*". Then a sweep for
for_each_cpu_mask => for_each_cpu.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: netdev@vger.kernel.org
This patch removes the use of the IRQF_DISABLED flag
It's a NOOP since 2.6.35 and it will be removed one day.
[dlezcano] : slightly changed the changelog
Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
This reverts commit 55a68c23e0.
In order to avoid a collision with dw_apb_timer changes in
the arm-soc tree, revert this change.
I'm leaving it to the arm-soc folks to sort out if they want
to keep the other side of the collision or if they're just going
to back it all out and try again during the next release cycle.
Reported-by: Dinh Nguyen <dinguyen@altera.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
It seems we made a mistake when creating dw_apb_timer_of.c:
picoxcell sched_clock had parts that were not related to
dw_apb_timer, yet we moved them to dw_apb_timer_of, and tried to
use them on socfpga.
This results in system where user/system time is not measured
properly, as demonstrated by
time dd if=/dev/urandom of=/dev/zero bs=100000 count=100
So this patch switches sched_clock to hardware that exists on both
platforms, and adds missing of_node_put() in dw_apb_timer_init().
Signed-off-by: Pavel Machek <pavel@denx.de>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
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>
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>
Jisheng Zhang
Viresh Kumar
Rusty Russell
Michael Opdenacker
John Stultz
Pavel Machek
Thomas Gleixner
Jamie Iles