Hello John,
2013/7/29 John Crispin <blogic@xxxxxxxxxxx>:
> On ralink SoC a secondary cevt exists, that shares irq 7 with the r4k timer.
> For this to work, we first need to teach cevt-r4k to not hog the irq.
It is not clear to me whether this secondary cevt is also a r4k-cevt
device, or if it is something else? If the IRQ is shared, is there any
way to differentiate the ralink cevt from the r4k cevt, such that both
could request the same irq with the IRQF_SHARED flag?
It looks to me like you are moving the irq setup later just to ensure
that your ralink clockevent device has been registered before and has
set cp0_timer_irq_installed when the set_mode() r4k clockevent device
runs, such that it won't register the same IRQ that your platforms
uses. If that it the case, cannot you just ensure that you run your
cevt device registration before mips_clockevent_init() is called?
>
> Signed-off-by: John Crispin <blogic@xxxxxxxxxxx>
> ---
> arch/mips/kernel/cevt-r4k.c | 39 ++++++++++++++++++++++++++-------------
> 1 file changed, 26 insertions(+), 13 deletions(-)
>
> diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c
> index 50d3f5a..b726422 100644
> --- a/arch/mips/kernel/cevt-r4k.c
> +++ b/arch/mips/kernel/cevt-r4k.c
> @@ -38,12 +38,6 @@ static int mips_next_event(unsigned long delta,
>
> #endif /* CONFIG_MIPS_MT_SMTC */
>
> -void mips_set_clock_mode(enum clock_event_mode mode,
> - struct clock_event_device *evt)
> -{
> - /* Nothing to do ... */
> -}
> -
> DEFINE_PER_CPU(struct clock_event_device, mips_clockevent_device);
> int cp0_timer_irq_installed;
>
> @@ -90,6 +84,32 @@ struct irqaction c0_compare_irqaction = {
> .name = "timer",
> };
>
> +void mips_set_clock_mode(enum clock_event_mode mode,
> + struct clock_event_device *evt)
> +{
> + switch (mode) {
> + case CLOCK_EVT_MODE_ONESHOT:
> + if (cp0_timer_irq_installed)
> + break;
> +
> + cp0_timer_irq_installed = 1;
> +
> + setup_irq(evt->irq, &c0_compare_irqaction);
> + break;
> +
> + case CLOCK_EVT_MODE_SHUTDOWN:
> + if (!cp0_timer_irq_installed)
> + break;
> +
> + cp0_timer_irq_installed = 0;
> + free_irq(evt->irq, &c0_compare_irqaction);
> + break;
> +
> + default:
> + pr_err("Unhandeled mips clock_mode\n");
> + break;
> + }
> +}
>
> void mips_event_handler(struct clock_event_device *dev)
> {
> @@ -215,13 +235,6 @@ int r4k_clockevent_init(void)
> #endif
> clockevents_register_device(cd);
>
> - if (cp0_timer_irq_installed)
> - return 0;
> -
> - cp0_timer_irq_installed = 1;
> -
> - setup_irq(irq, &c0_compare_irqaction);
> -
> return 0;
> }
>
> --
> 1.7.10.4
--
Florian
