All the clocksource drivers's init function are now converted to return
an error code. CLOCKSOURCE_OF_DECLARE is no longer used as well as the
clksrc-of table.

Let's convert back the names:
 - CLOCKSOURCE_OF_DECLARE_RET => CLOCKSOURCE_OF_DECLARE
 - clksrc-of-ret              => clksrc-of

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

For exynos_mct and samsung_pwm_timer:
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

For arch/arc:
Acked-by: Vineet Gupta <vgupta@synopsys.com>

For mediatek driver:
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>

For the Rockchip-part
Acked-by: Heiko Stuebner <heiko@sntech.de>

For STi :
Acked-by: Patrice Chotard <patrice.chotard@st.com>

For the mps2-timer.c and versatile.c changes:
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>

For the OXNAS part :
Acked-by: Neil Armstrong <narmstrong@baylibre.com>

For LPC32xx driver:
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>

For Broadcom Kona timer change:
Acked-by: Ray Jui <ray.jui@broadcom.com>

For Sun4i and Sun5i:
Acked-by: Chen-Yu Tsai <wens@csie.org>

For Meson6:
Acked-by: Carlo Caione <carlo@caione.org>

For Keystone:
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>

For NPS:
Acked-by: Noam Camus <noamca@mellanox.com>

For bcm2835:
Acked-by: Eric Anholt <eric@anholt.net>

The init functions do not return any error. They behave as the following:

 - panic, thus leading to a kernel crash while another timer may work and
   make the system boot up correctly

 or

 - print an error and let the caller unaware if the state of the system

Change that by converting the init functions to return an error conforming
to the CLOCKSOURCE_OF_RET prototype.

Proper error handling (rollback, errno value) will be changed later case
by case, thus this change just return back an error or success in the init
function.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Implement an ARM delay timer to be used for udelay(). This allows us to
skip the delay loop calibration at boot on Marvell BG2, BG2Q, BG2CD
platforms. And after this patch, udelay() will be unaffected by CPU
frequency changes.

Note: Although in case there are several possible delay timers, we may
not select the "best" delay timer. Take one Marvell Berlin platform for
example: we have arch timer and dw-apb timer. The arch timer freq is
25MHZ while the dw-apb timer freq is 100MHZ, current selection would
choose the dw-apb timer. But the dw apb timer is on the APB bus while
arch timer sits in CPU, the cost of accessing the apb timer is higher
than the arch timer. We could introduce "rating" concept to delay
timer, but this approach "brings a lot of complexity and workarounds
in the code for a small benefit" as pointed out by Daniel.

Later, Arnd pointed out "However, we could argue that this actually
doesn't matter at all, because the entire point of the ndelay()/
udelay()/mdelay() functions is to waste CPU cycles doing not much at
all, so we can just as well waste them reading the timer register
than spinning on the CPU reading the arch timer more often.", so we
just simply register the dw apb base delay timer.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

The dw_apb_timer_of timer is using __raw_readl() to access the
timer register, which is causing issues when the system is
running in big endian mode. Fix this by using readl_relaxed()
which should account for the endian settings.

This fixes issues where the time jumps around in the dmesg
output due to returnling __le32 values.

For an example, these two console lines show time running
backwards:

[   49.882572] CPU1: failed to come online
[   43.282457] Brought up 1 CPUs

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Linux ARM Kernel <linux-arm-kernel@lists.infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: digetx@gmail.com
Cc: hdegoede@redhat.com
Cc: laurent.pinchart+renesas@ideasonboard.com
Cc: maxime.ripard@free-electrons.com
Cc: viresh.kumar@linaro.org
Link: http://lkml.kernel.org/r/1427746633-9137-10-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

We do not need to trace read_sched_clock function,
so add notrace attribute for this function.

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

In commit 620f5e1cbf (dts: Rename DW APB timer compatible strings), both
"snps,dw-apb-timer-sp" and "snps,dw-apb-timer-osc" were deprecated in place
of "snps,dw-apb-timer". But the driver also needs to be udpated in order to
support this new binding "snps,dw-apb-timer".

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

The read_sched_clock should return the ~value because the clock is a
countdown implementation. read_sched_clock() should be the same as
 __apbt_read_clocksource().

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

These are all only called by dw_apb_timer_init which is an __init
function, too

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Instead of letting each driver call of_node_put do it centrally in the
loop that also calls the CLOCKSOURCE_OF_DECLARE callbacks. This is less
prone to error and also moves getting and putting the references into the
same function.

Consequently all respective of_node_put calls in drivers are removed.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: David Brown <davidb@codeaurora.org>

The 32 bit sched_clock interface now supports 64 bits. Upgrade to
the 64 bit function to allow us to remove the 32 bit registration
interface.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>