Re: [PATCH v2 4/6] clocksource: Change CPU hotplug priority of exynos_mct driver

Chanwoo Choi
2018-10-16T00:59:32Z

On 2018년 10월 15일 21:31, Marek Szyprowski wrote:
> Exynos Multi-Core Timer driver (exynos_mct) must be started before
> ARM Architected Timers (arch_timer), because both timers share common
> hardware block and turning on MCT is needed to get ARM Architected
> Timer working properly.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
> ---
> include/linux/cpuhotplug.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
> index caf40ad0bbc6..5d9e4a6ea299 100644
> --- a/include/linux/cpuhotplug.h
> +++ b/include/linux/cpuhotplug.h
> @@ -115,10 +115,10 @@ enum cpuhp_state {
> CPUHP_AP_PERF_ARM_ACPI_STARTING,
> CPUHP_AP_PERF_ARM_STARTING,
> CPUHP_AP_ARM_L2X0_STARTING,
> + CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
> CPUHP_AP_ARM_ARCH_TIMER_STARTING,
> CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
> CPUHP_AP_JCORE_TIMER_STARTING,
> - CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
> CPUHP_AP_ARM_TWD_STARTING,
> CPUHP_AP_QCOM_TIMER_STARTING,
> CPUHP_AP_ARMADA_TIMER_STARTING,
>

On Exynos SoC, ARM architecture timer shares the block of Exynos MCT timer.
For using arch_timer, Exynos MCT timer should be initialized before arch_timer.
I agree about this.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>

--
Best Regards,
Chanwoo Choi
Samsung Electronics