From ec5c8e429d07737ee94ee1fd2ae5029547484194 Mon Sep 17 00:00:00 2001 From: Julien Thierry Date: Fri, 13 Oct 2017 14:32:55 +0100 Subject: arm_arch_timer: Expose event stream status The arch timer configuration for a CPU might get reset after suspending said CPU. In order to reliably use the event stream in the kernel (e.g. for delays), we keep track of the state where we can safely consider the event stream as properly configured. After writing to cntkctl, we issue an ISB to ensure that subsequent delay loops can rely on the event stream being enabled. Signed-off-by: Julien Thierry Acked-by: Mark Rutland Cc: Marc Zyngier Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon --- include/clocksource/arm_arch_timer.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/clocksource') diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h index cc805b72994a..4e28283e2ec6 100644 --- a/include/clocksource/arm_arch_timer.h +++ b/include/clocksource/arm_arch_timer.h @@ -93,6 +93,7 @@ struct arch_timer_mem { extern u32 arch_timer_get_rate(void); extern u64 (*arch_timer_read_counter)(void); extern struct arch_timer_kvm_info *arch_timer_get_kvm_info(void); +extern bool arch_timer_evtstrm_available(void); #else @@ -106,6 +107,11 @@ static inline u64 arch_timer_read_counter(void) return 0; } +static inline bool arch_timer_evtstrm_available(void) +{ + return false; +} + #endif #endif -- cgit v1.2.3