Hi Marek, On 19. 3. 21. 오후 5:26, Marek Szyprowski wrote: > Exynos Multi-Core Timer driver (exynos_mct) must be 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. Increase MCT timer rating > and hotplug priority over ARM Archictected timer driver to achieve that. > > Signed-off-by: Marek Szyprowski <m.szyprow...@samsung.com> > Reviewed-by: Krzysztof Kozlowski <k...@kernel.org> > --- > v2: added comments about the relation to ARM arch timer > rebased onto v5.1-rc1 > v1: https://patchwork.kernel.org/patch/10814921/ > --- > drivers/clocksource/exynos_mct.c | 4 ++-- > include/linux/cpuhotplug.h | 2 +- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/clocksource/exynos_mct.c > b/drivers/clocksource/exynos_mct.c > index 34bd250d46c6..6aa10cbc1d59 100644 > --- a/drivers/clocksource/exynos_mct.c > +++ b/drivers/clocksource/exynos_mct.c > @@ -209,7 +209,7 @@ static void exynos4_frc_resume(struct clocksource *cs) > > static struct clocksource mct_frc = { > .name = "mct-frc", > - .rating = 400, > + .rating = 450, /* use value higher than ARM arch timer */ > .read = exynos4_frc_read, > .mask = CLOCKSOURCE_MASK(32), > .flags = CLOCK_SOURCE_IS_CONTINUOUS, > @@ -464,7 +464,7 @@ static int exynos4_mct_starting_cpu(unsigned int cpu) > evt->set_state_oneshot_stopped = set_state_shutdown; > evt->tick_resume = set_state_shutdown; > evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; > - evt->rating = 450; > + evt->rating = 500; /* use value higher than ARM arch timer */ > > exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET); > > diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h > index e78281d07b70..53fb48de9589 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_TEGRA_TIMER_STARTING, >
As the cover-letter, the arch-timer of Exynos SoC used the h/w block of MCT. I agree. Reviewed-by: Chanwoo Choi <cw00.c...@samsung.com> -- Best Regards, Chanwoo Choi Samsung Electronics
