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

Message ID 20181015123112.9379-5-m.szyprowski@samsung.com
State New
Headers show
Series
  • Proper arch timer support for Exynos5433-based TM2(e) boards
Related show

Commit Message

Marek Szyprowski Oct. 15, 2018, 12:31 p.m.
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(-)

-- 
2.17.1

Comments

Chanwoo Choi Oct. 16, 2018, 12:59 a.m. | #1
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

Patch

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,