Hi Anson,
why did you resend the series?
On 02/07/2019 09:55, Anson.Huang@xxxxxxx wrote:
> From: Anson Huang <Anson.Huang@xxxxxxx>
>
> More and more platforms use platform driver model for clock driver,
> so the clock driver is NOT ready during timer initialization phase,
> it will cause timer initialization failed.
>
> To support those platforms with upper scenario, introducing a new
> flag TIMER_OF_CLOCK_FREQUENCY which is mutually exclusive with
> TIMER_OF_CLOCK flag to support getting timer clock frequency from
> DT's timer node, the property name should be "clock-frequency",
> then of_clk operations can be skipped.
>
> User needs to select either TIMER_OF_CLOCK_FREQUENCY or TIMER_OF_CLOCK
> flag if want to use timer-of driver to initialize the clock rate.
>
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> ---
> Changes since V3:
> - use hardcoded "clock-frequency" instead of adding new variable prop_name;
> - add pre-condition check for TIMER_OF_CLOCK and TIMER_OF_CLOCK_FREQUENCY, they MUST be exclusive.
> ---
> drivers/clocksource/timer-of.c | 29 +++++++++++++++++++++++++++++
> drivers/clocksource/timer-of.h | 7 ++++---
> 2 files changed, 33 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/clocksource/timer-of.c b/drivers/clocksource/timer-of.c
> index 8054228..858f684 100644
> --- a/drivers/clocksource/timer-of.c
> +++ b/drivers/clocksource/timer-of.c
> @@ -161,11 +161,30 @@ static __init int timer_of_base_init(struct device_node *np,
> return 0;
> }
>
> +static __init int timer_of_clk_frequency_init(struct device_node *np,
> + struct of_timer_clk *of_clk)
> +{
> + int ret;
> + u32 rate;
> +
> + ret = of_property_read_u32(np, "clock-frequency", &rate);
> + if (!ret) {
> + of_clk->rate = rate;
> + of_clk->period = DIV_ROUND_UP(rate, HZ);
> + }
> +
> + return ret;
> +}
> +
> int __init timer_of_init(struct device_node *np, struct timer_of *to)
> {
> + unsigned long clock_flags = TIMER_OF_CLOCK | TIMER_OF_CLOCK_FREQUENCY;
> int ret = -EINVAL;
> int flags = 0;
>
> + if ((to->flags & clock_flags) == clock_flags)
> + return ret;
> +
> if (to->flags & TIMER_OF_BASE) {
> ret = timer_of_base_init(np, &to->of_base);
> if (ret)
> @@ -180,6 +199,13 @@ int __init timer_of_init(struct device_node *np, struct timer_of *to)
> flags |= TIMER_OF_CLOCK;
> }
>
> + if (to->flags & TIMER_OF_CLOCK_FREQUENCY) {
> + ret = timer_of_clk_frequency_init(np, &to->of_clk);
> + if (ret)
> + goto out_fail;
> + flags |= TIMER_OF_CLOCK_FREQUENCY;
> + }
> +
> if (to->flags & TIMER_OF_IRQ) {
> ret = timer_of_irq_init(np, &to->of_irq);
> if (ret)
> @@ -201,6 +227,9 @@ int __init timer_of_init(struct device_node *np, struct timer_of *to)
> if (flags & TIMER_OF_CLOCK)
> timer_of_clk_exit(&to->of_clk);
>
> + if (flags & TIMER_OF_CLOCK_FREQUENCY)
> + to->of_clk.rate = 0;
> +
> if (flags & TIMER_OF_BASE)
> timer_of_base_exit(&to->of_base);
> return ret;
> diff --git a/drivers/clocksource/timer-of.h b/drivers/clocksource/timer-of.h
> index a5478f3..a08e108 100644
> --- a/drivers/clocksource/timer-of.h
> +++ b/drivers/clocksource/timer-of.h
> @@ -4,9 +4,10 @@
>
> #include <linux/clockchips.h>
>
> -#define TIMER_OF_BASE 0x1
> -#define TIMER_OF_CLOCK 0x2
> -#define TIMER_OF_IRQ 0x4
> +#define TIMER_OF_BASE 0x1
> +#define TIMER_OF_CLOCK 0x2
> +#define TIMER_OF_IRQ 0x4
> +#define TIMER_OF_CLOCK_FREQUENCY 0x8
>
> struct of_timer_irq {
> int irq;
>
--
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