Setup scheduler clock on ARM MXS platforms with a 32-bit timrot
such as i.MX28. This allows the scheduler to use sub-jiffy resolution.
The corresponding change for 16-bit v1 timrots is not possible
at the moment due to rounding issues with clock values wrapping
faster than once per several seconds in the common ARM platform code.
Signed-off-by: Stanislav Meduna <stano@meduna.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Rather than using the static timer irq definition, we should retrieve
timer irq from device tree for better.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
With old mxs clock support removed, the timer_clk argument of
mxs_timer_init is unused now, so remove it.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
When mxs_timer_init() does not have a timer_clk passed in, it should
try to request clock from clkdev system.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
The patch converts mxs platform code to clk_prepare/clk_unprepare
by using helper functions clk_prepare_enable/clk_disable_unprepare.
Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Convert the MXS timrotv2 32-bit down counting clocksource to the
generic clocksource infrastructure.
Cc: Sascha Hauer <kernel@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There are 2 versions of the timrot on Freescale MXS-based SoCs.
The v1 on MX23 only gets 16 bits counter, while v2 on MX28
extends the counter to 32 bits.
The implementation uses two timers, one for clock_event and
another for clocksource. MX28 uses timrot 0 and 1, while MX23
uses 0 and 2.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
