run without lapic and ioapic, if they are not present

if no lapic available, use 8253pit for clock
now xv6 runs both on qemu (uniprocessor) and bochs (uniprocessor and MP)

1 files changed, 6 insertions, 0 deletions

diff --git a/defs.h b/defs.h
index 85f0085..fb48700 100644
--- a/defs.h
+++ b/defs.h
@@ -49,9 +49,15 @@ int checkstring(uint);
 int putint(struct proc*, uint, int);
 
 // picirq.c
+extern ushort irq_mask_8259A;
 void pic_init(void);
+void irq_setmask_8259A(ushort);
+
+// 8253pit.c
+void pit8253_timerinit(void);
 
 // mp.c
+extern int ismp;
 void mp_init(void);
 void mp_startthem(void);
 int mp_bcpu(void);