apic clockevents: per-cpu setup

The apic needs to be programmed on each cpu that is brought up.

arch/x64/apic-clock.cc

@@ -9,6 +9,7 @@ class apic_clock_events : public clock_event_driver {
 public:
     explicit apic_clock_events();
     ~apic_clock_events();
+    virtual void setup_on_cpu();
     virtual void set(u64 time);
 private:
     unsigned _vector;
@@ -17,15 +18,19 @@ private:
 apic_clock_events::apic_clock_events()
     : _vector(idt.register_handler([this] { _callback->fired(); }))
 {
-    processor::apic->write(apicreg::TMDCR, 0xb); // divide by 1
-    processor::apic->write(apicreg::TMICT, 0);
-    processor::apic->write(apicreg::LVTT, _vector); // one-shot
 }
 
 apic_clock_events::~apic_clock_events()
 {
 }
 
+void apic_clock_events::setup_on_cpu()
+{
+    processor::apic->write(apicreg::TMDCR, 0xb); // divide by 1
+    processor::apic->write(apicreg::TMICT, 0);
+    processor::apic->write(apicreg::LVTT, _vector); // one-shot
+}
+
 void apic_clock_events::set(u64 time)
 {
     u64 now = clock::get()->time();

core/sched.cc

@@ -64,6 +64,7 @@ void cpu::handle_incoming_wakeups()
 void cpu::init_on_cpu()
 {
     arch.init_on_cpu();
+    clock_event->setup_on_cpu();
 }
 
 void schedule(bool yield)

drivers/clockevent.hh

@@ -13,6 +13,7 @@ public:
 class clock_event_driver {
 public:
     virtual ~clock_event_driver();
+    virtual void setup_on_cpu() = 0;
     // set() is cpu-local: each processor has its own timer
     virtual void set(u64 time) = 0;
     void set_callback(clock_event_callback* callback);