Re: [PATCH] MIPS: kernel: only use i8253 clocksource with periodic clockevent

From: Thomas Bogendoerfer
Date: Wed Jul 17 2019 - 05:04:04 EST


On Mon, May 13, 2019 at 01:47:25PM +0200, Thomas Bogendoerfer wrote:
> i8253 clocksource needs a free running timer. This could only
> be used, if i8253 clockevent is set up as periodic.
>
> Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@xxxxxxx>
> ---
> arch/mips/kernel/i8253.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/mips/kernel/i8253.c b/arch/mips/kernel/i8253.c
> index 5f209f111e59..df7ddd246eaa 100644
> --- a/arch/mips/kernel/i8253.c
> +++ b/arch/mips/kernel/i8253.c
> @@ -32,7 +32,8 @@ void __init setup_pit_timer(void)
>
> static int __init init_pit_clocksource(void)
> {
> - if (num_possible_cpus() > 1) /* PIT does not scale! */
> + if (num_possible_cpus() > 1 || /* PIT does not scale! */
> + !clockevent_state_periodic(&i8253_clockevent))
> return 0;
>
> return clocksource_i8253_init();
> --
> 2.13.7

Paul,

can you take it into 5.3 ? This fixes a boot ang on mips/jazz and
is the same as x86 does for quite some time.

Thomas.

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