On 30/05/2019 12:50, Marek Szyprowski wrote: > Exynos SoCs based on CA7/CA15 have 2 timer interfaces: custom Exynos MCT > (Multi Core Timer) and standard ARM Architected Timers. > > There are use cases, where both timer interfaces are used simultanously. > One of such examples is using Exynos MCT for the main system timer and > ARM Architected Timers for the KVM and virtualized guests (KVM requires > arch timers). > > Exynos Multi-Core Timer driver (exynos_mct) must be however started > before ARM Architected Timers (arch_timer), because they both share some > common hardware blocks (global system counter) and turning on MCT is > needed to get ARM Architected Timer working properly. > > To ensure selecting Exynos MCT as the main system timer, increase MCT > timer rating. To ensure proper starting order of both timers during > suspend/resume cycle, increase MCT hotplug priority over ARM Archictected > Timers. > > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx> > Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx> > --- Applied thanks! -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog
