clocksource/drivers/imx-tpm: Add imx tpm timer support
authorDong Aisheng <aisheng.dong@nxp.com>
Tue, 1 Aug 2017 08:40:17 +0000 (16:40 +0800)
committerDaniel Lezcano <daniel.lezcano@linaro.org>
Tue, 29 Aug 2017 09:07:56 +0000 (11:07 +0200)
commit059ab7b82eecfc23bc58c491d72ee6b424163578
treeadf2612e76cf6331fae6abb7ccab324808941a80
parent34b0c26cd5458a991626bc8424e029562dceed21
clocksource/drivers/imx-tpm: Add imx tpm timer support

IMX Timer/PWM Module (TPM) supports both timer and pwm function while
this patch only adds the timer support. PWM would be added later.

The TPM counter, compare and capture registers are clocked by an
asynchronous clock that can remain enabled in low power modes.

NOTE: We observed in a very small probability, the bus fabric
contention between GPU and A7 may results a few cycles delay
of writing CNT registers which may cause the min_delta event got
missed, so we need add a ETIME check here in case it happened.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Anson Huang <Anson.Huang@nxp.com>
Cc: Bai Ping <ping.bai@nxp.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
drivers/clocksource/Kconfig
drivers/clocksource/Makefile
drivers/clocksource/timer-imx-tpm.c [new file with mode: 0644]