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5 commits

Author SHA1 Message Date
Colin Ian King
3d95c576aa clocksource/drivers/fsl_ftm_timer: Fix error return checking
[ Upstream commit f287eb9013ccf199cbfa4eabd80c36fedfc15a73 ]

The error checks on freq for a negative error return always fails because
freq is unsigned and can never be negative. Fix this by making freq a
signed long.

Detected with Coccinelle:
drivers/clocksource/fsl_ftm_timer.c:287:5-9: WARNING: Unsigned expression
compared with zero: freq <= 0
drivers/clocksource/fsl_ftm_timer.c:291:5-9: WARNING: Unsigned expression
compared with zero: freq <= 0

Fixes: 2529c3a330 ("clocksource: Add Freescale FlexTimer Module (FTM) timer support")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: kernel-janitors@vger.kernel.org
Link: https://lkml.kernel.org/r/20180226113614.3092-1-colin.king@canonical.com
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:49:01 +02:00
Arnd Bergmann
dde7632ed0 clocksource/fsl: Avoid harmless 64-bit warnings
The ftm_clockevent_init passes the value of "~0UL" into a function
that takes a 32-bit argument, which drops the upper 32 bits, as
gcc warns about on ARM64:

clocksource/fsl_ftm_timer.c: In function 'ftm_clockevent_init':
clocksource/fsl_ftm_timer.c:206:13: warning: large integer implicitly truncated to unsigned type [-Woverflow]

This was obviously unintended behavior, and is easily avoided by
using '~0u' as the integer literal, because that is 32-bit wide
on all architectures.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Xiubo Li <Li.Xiubo@freescale.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: http://lkml.kernel.org/r/3990834.xnjhm37Grs@wuerfel
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-11-16 19:07:08 +01:00
Jisheng Zhang
bd859a44b2 clocksource/drivers/fsl_ftm_timer: Prevent ftrace recursion
Having a traceable function in the sched_clock() path leads to a recursion
within ftrace and a kernel crash.

We should not trace the ftm_read_sched_clock() function.

Fix this by adding the notrace attribute to this function.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-10-27 01:34:07 +01:00
Viresh Kumar
7376634018 clockevents/drivers/fsl_ftm: Migrate to new 'set-state' interface
Migrate fsl_ftm 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: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-08-10 11:40:29 +02:00
Xiubo Li
2529c3a330 clocksource: Add Freescale FlexTimer Module (FTM) timer support
The Freescale FlexTimer Module time reference is a 16-bit counter
that can be used as an unsigned or signed increase counter.

CNTIN defines the starting value of the count and MOD defines the
final value of the count. The value of CNTIN is loaded into the FTM
counter, and the counter increments until the value of MOD is reached,
at which point the counter is reloaded with the value of CNTIN. That's
also when an overflow interrupt will be generated.

Here using the 'evt' prefix or postfix as clock event device and
the 'src' as clock source device.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Jingchang Lu <b35083@freescale.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-05-23 10:12:04 +02:00