Re: [PATCH v2 3/6] clocksource/drivers/tegra: Set and use timer's period

From: Jon Hunter
Date: Fri Jun 14 2019 - 11:53:28 EST



On 10/06/2019 17:43, Dmitry Osipenko wrote:
> The of_clk structure has a period field that is set up initially by
> timer_of_clk_init(), that period value need to be adjusted for a case of
> TIMER1-9 that are running at a fixed rate that doesn't match the clock's
> rate. Note that the period value is currently used only by some of the
> clocksource drivers internally and hence this is just a minor cleanup
> change that doesn't fix anything.
>
> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
> ---
> drivers/clocksource/timer-tegra.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clocksource/timer-tegra.c b/drivers/clocksource/timer-tegra.c
> index 810b4e7435cf..646b3530c2d2 100644
> --- a/drivers/clocksource/timer-tegra.c
> +++ b/drivers/clocksource/timer-tegra.c
> @@ -71,9 +71,9 @@ static int tegra_timer_shutdown(struct clock_event_device *evt)
> static int tegra_timer_set_periodic(struct clock_event_device *evt)
> {
> void __iomem *reg_base = timer_of_base(to_timer_of(evt));
> + unsigned long period = timer_of_period(to_timer_of(evt));
>
> - writel_relaxed(TIMER_PTV_EN | TIMER_PTV_PER |
> - ((timer_of_rate(to_timer_of(evt)) / HZ) - 1),
> + writel_relaxed(TIMER_PTV_EN | TIMER_PTV_PER | (period - 1),
> reg_base + TIMER_PTV);
>
> return 0;
> @@ -297,6 +297,7 @@ static int __init tegra_init_timer(struct device_node *np, bool tegra20,
> cpu_to->clkevt.rating = rating;
> cpu_to->clkevt.cpumask = cpumask_of(cpu);
> cpu_to->of_base.base = timer_reg_base + base;
> + cpu_to->of_clk.period = DIV_ROUND_UP(rate, HZ);

Any reason you made this a round-up?

Jon

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nvpublic