kernel/arm: fix system_time for generic timer

Change-Id: Ief7b0638f40ba5deee27f3551e8870bfb6216a4d
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5569
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Fredrik Holmqvist <[email protected]>

src/system/kernel/arch/arm/arch_timer_generic.cpp

@@ -35,7 +35,7 @@ get_counter(void)
 void
 ARMGenericTimer::SetTimeout(bigtime_t timeout)
 {
-	uint32_t timeout_ticks = timeout * fTimerFrequency / 1000000;
+	uint32_t timeout_ticks = timeout * fTimerFrequencyMHz;
 	asm volatile ("ISB\n"
 		"MCR p15, 0, %0, c14, c2, 0"
 		: : "r"(timeout_ticks));
@@ -58,7 +58,7 @@ ARMGenericTimer::Clear()
 bigtime_t
 ARMGenericTimer::Time()
 {
-	return get_counter() / fTimerFrequency;
+	return get_counter() / fTimerFrequencyMHz;
 }
 
 
@@ -85,6 +85,7 @@ ARMGenericTimer::ARMGenericTimer()
 		&ARMGenericTimer::_InterruptWrapper, this, 0);
 
 	fTimerFrequency = get_counter_freq();
+	fTimerFrequencyMHz = fTimerFrequency / 1000000;
 }
 
 

src/system/kernel/arch/arm/arch_timer_generic.h

@@ -30,6 +30,7 @@ private:
 	int32 HandleInterrupt();
 
 	uint32_t fTimerFrequency;
+	uint32_t fTimerFrequencyMHz;
 };
 
 #endif /* ARCH_ARM_TIMER_GENERIC_H */