On 23/06/2019 14:38, Anson.Huang@xxxxxxx wrote:
> From: Anson Huang <Anson.Huang@xxxxxxx>
>
> On some i.MX8M platforms, clock driver uses platform driver
> model and it is NOT ready during timer initialization phase,
> the clock operations will fail and system counter driver will
> fail too. As all the i.MX8M platforms' system counter clock
> are from OSC which is always enabled, so it is no need to enable
> clock for system counter driver, the ONLY thing is to pass
> clock frequence to driver.
>
> To make system counter driver work for upper scenario, add an
> option of skipping of_clk operation for system counter driver,
> an optional property "clock-frequency" is introduced to pass
> the frequency value to system counter driver and indicate driver
> to skip of_clk operations.
>
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> ---
> Changes since V1:
> - improve commit log, no content change.
> ---
> drivers/clocksource/timer-imx-sysctr.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/clocksource/timer-imx-sysctr.c b/drivers/clocksource/timer-imx-sysctr.c
> index fd7d680..8ff3d7e 100644
> --- a/drivers/clocksource/timer-imx-sysctr.c
> +++ b/drivers/clocksource/timer-imx-sysctr.c
> @@ -129,6 +129,14 @@ static void __init sysctr_clockevent_init(void)
> static int __init sysctr_timer_init(struct device_node *np)
> {
> int ret = 0;
> + u32 rate;
> +
> + if (!of_property_read_u32(np, "clock-frequency",
> + &rate)) {
> + to_sysctr.of_clk.rate = rate;
> + to_sysctr.of_clk.period = DIV_ROUND_UP(rate, HZ);
> + to_sysctr.flags &= ~TIMER_OF_CLOCK;
> + }
Please take the opportunity to add the TIMER_OF_CLOCK_FREQUENCY flag in
timer-of and the corresponding code above.
Then check the clock-frequency presence and add TIMER_OF_CLOCK or
TIMER_OF_CLOCK_FREQUENCY flag to the timer-of structure.
eg:
to_sysctr.flags |= of_find_property(np, "clock-frequency", NULL) ?
TIMER_OF_CLOCK_FREQUENCY : TIMER_OF_CLOCK;
> ret = timer_of_init(np, &to_sysctr);
> if (ret)
>
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