Re: [PATCH v3 4/6] clocksource: exynos_mct: Add arch_timer cooperation mode for ARM64

From: Chanwoo Choi
Date: Wed Oct 17 2018 - 23:51:13 EST


Hi Marek,

On 2018ë 10ì 17ì 22:41, Marek Szyprowski wrote:
> To get ARM Architected Timers working on Samsung Exynos SoCs, one has to
> first configure and enable Exynos Multi-Core Timer, because they both
> share some common hardware blocks (global system counter). This patch
> adds a mode of cooperation with arch_timer driver, so kernel can use
> CP15 based timer interface via arch_timer driver, which is mandatory
> on ARM64. In such mode MCT driver only enables its clocks and starts
> global timer. Everything else will be handled by arch_timer driver.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> ---
> drivers/clocksource/exynos_mct.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
> index 02ad55db390b..1b19a4f03929 100644
> --- a/drivers/clocksource/exynos_mct.c
> +++ b/drivers/clocksource/exynos_mct.c
> @@ -606,6 +606,15 @@ static int __init mct_init_dt(struct device_node *np, unsigned int int_type)
> if (ret)
> return ret;
>
> + if (IS_ENABLED(CONFIG_ARM64) && IS_ENABLED(CONFIG_ARM_ARCH_TIMER)) {
> + struct device_node *np = of_find_compatible_node(NULL, NULL,
> + "arm,armv8-timer");
> + if (np) {
> + of_node_put(np);
> + exynos4_mct_frc_start();
> + return 0;
> + }
> + }
>
> ret = exynos4_timer_interrupts(np, int_type);
> if (ret)
>

I tested it on Exynos5433-based TM2 board.

Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Tested-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>


--
Best Regards,
Chanwoo Choi
Samsung Electronics