Commit graph

5 commits

Author SHA1 Message Date
Ezequiel Garcia
1b18fd2023 clocksource/drivers/lpc32xx: Support timer-based ARM delay
This commit implements the ARM timer-based delay timer for the
LPC32xx, LPC18xx, LPC43xx family of SoCs.

Also, add a dependency to restrict compiling this driver for
the ARM architecture.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Joachim Eastwood <manabian@gmail.com>
Tested-by: Joachim Eastwood <manabian@gmail.com>
2016-02-25 14:33:58 +01:00
Ezequiel Garcia
32f32d982f clocksource/drivers/lpc32xx: Support periodic mode
This commit adds the support for periodic mode. This is done by not
setting the MR0S (Stop on TnMR0) bit on MCR, thus allowing
interrupts to be periodically generated on MR0 matches.

In order to do this, move the initial configuration that is specific to
the one-shot mode to set_state_oneshot().

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Joachim Eastwood <manabian@gmail.com>
Tested-by: Joachim Eastwood <manabian@gmail.com>
2016-02-25 14:30:20 +01:00
Ezequiel Garcia
751db1a6ea clocksource/drivers/lpc32xx: Don't use the prescaler counter for clockevents
This commit switches the clockevents one-shot current implementation
to avoid using the prescaler counter. The clockevents timer currently
uses MR0=1, PR=ticks; and after this commit is uses MR0=ticks, PR=0.

While using the prescaler with PR=1 works fine in one-shot mode,
it seems it doesn't work as expected in periodic mode.

By using the only match channel register (MR0) for the timer we make
the periodic mode introduction easier, and consistent with one-shot mode.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Joachim Eastwood <manabian@gmail.com>
Tested-by: Joachim Eastwood <manabian@gmail.com>
2016-02-25 14:30:19 +01:00
Vladimir Zapolskiy
d662ed2043 clocksource/drivers/lpc32: Correct pr_err() output format
If by some reason timerclk is not available, both clockevent and
clocksource initializations correctly exit, but output of errno to
kernel log buffer may be confusing:

  lpc32xx_clk_init: failed to map system control block registers
  lpc32xx_clocksource_init: clock get failed (4294966779)
  lpc32xx_clockevent_init: clock get failed (4294966779)

Use signed integer output in the correspondent pr_err() string formats:

  lpc32xx_clocksource_init: clock get failed (-517)
  lpc32xx_clockevent_init: clock get failed (-517)

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-12-16 09:59:41 +01:00
Joachim Eastwood
050dd3222b clocksource/drivers/lpc32xx: Add the lpc32xx timer driver
Add support for using the NXP LPC timer as clocksource and clock
event. These timers are present on many NXP devices including
LPC32xx, LPC17xx, LPC18xx and LPC43xx.

The timer has a 32-bit timer counter register with a programmable
32-bit prescaler. It supports up to 4 compare match values with
interrupt generation and reset/stop timer counter action.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-06-02 12:10:10 +02:00