[PATCH v2 3/3] clocksource/drivers/lpc32xx: Support timer-based ARM delay

[Joachim Eastwood]

On 10 February 2016 at 02:54, Ezequiel Garcia
<ezequiel at vanguardiasur.com.ar> wrote:
> 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 at vanguardiasur.com.ar>
> ---
>  drivers/clocksource/Kconfig        |  1 +
>  drivers/clocksource/time-lpc32xx.c | 12 ++++++++++++
>  2 files changed, 13 insertions(+)
>
> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
> index 33db7406c0e2..c346be650892 100644
> --- a/drivers/clocksource/Kconfig
> +++ b/drivers/clocksource/Kconfig
> @@ -160,6 +160,7 @@ config CLKSRC_EFM32
>  config CLKSRC_LPC32XX
>         bool "Clocksource for LPC32XX" if COMPILE_TEST
>         depends on GENERIC_CLOCKEVENTS && HAS_IOMEM
> +       depends on ARM
>         select CLKSRC_MMIO
>         select CLKSRC_OF
>         help
> diff --git a/drivers/clocksource/time-lpc32xx.c b/drivers/clocksource/time-lpc32xx.c
> index 5694eddade15..daae61e8c820 100644
> --- a/drivers/clocksource/time-lpc32xx.c
> +++ b/drivers/clocksource/time-lpc32xx.c
> @@ -18,6 +18,7 @@
>  #include <linux/clk.h>
>  #include <linux/clockchips.h>
>  #include <linux/clocksource.h>
> +#include <linux/delay.h>
>  #include <linux/interrupt.h>
>  #include <linux/irq.h>
>  #include <linux/kernel.h>
> @@ -54,6 +55,15 @@ static u64 notrace lpc32xx_read_sched_clock(void)
>         return readl(clocksource_timer_counter);
>  }
>
> +static unsigned long lpc32xx_delay_timer_read(void)
> +{
> +       return readl(clocksource_timer_counter);
> +}
> +
> +static struct delay_timer lpc32xx_delay_timer = {
> +       .read_current_timer = lpc32xx_delay_timer_read,
> +};
> +
>  static int lpc32xx_clkevt_next_event(unsigned long delta,
>                                      struct clock_event_device *evtdev)
>  {
> @@ -192,6 +202,8 @@ static int __init lpc32xx_clocksource_init(struct device_node *np)
>         }
>
>         clocksource_timer_counter = base + LPC32XX_TIMER_TC;
> +       lpc32xx_delay_timer.freq = rate;
> +       register_current_timer_delay(&lpc32xx_delay_timer);
>         sched_clock_register(lpc32xx_read_sched_clock, 32, rate);
>
>         return 0;

Reviewed-by: Joachim Eastwood <manabian at gmail.com>
Tested-by: Joachim Eastwood <manabian at gmail.com>

Boot tested on EA4357.

regards,
Joachim Eastwood