Clean up lapic code.

One initialization function now, not three. Use #defines instead of enums (consistent with other code, but sigh). Still boots in Bochs in SMP mode.

Clean up lapic code.
b63bb0fd · rsc · 112873bc · b63bb0fd · b63bb0fd · b63bb0fd
--- a/defs.h
+++ b/defs.h
@@ -69,12 +69,12 @@ void            kinit(void);
 // lapic.c
 int             cpu(void);
-extern uint*    lapicaddr;
+extern volatile uint*    lapic;
 void            lapic_disableintr(void);
 void            lapic_enableintr(void);
 void            lapic_eoi(void);
 void            lapic_init(int);
-void            lapic_startap(uchar, int);
+void            lapic_startap(uchar, uint);
 void            lapic_timerinit(void);
 void            lapic_timerintr(void);

--- a/lapic.c
+++ b/lapic.c
--- a/main.c
+++ b/main.c
@@ -37,7 +37,6 @@ main0(void)
  asm volatile("movl %0, %%ebp" : : "r" (cpus[bcpu].mpstack+MPSTACK));
  lapic_init(bcpu);
  cprintf("\ncpu%d: starting xv6\n\n", cpu());
  pinit();         // process table
@@ -53,10 +52,7 @@ main0(void)
  console_init();  // I/O devices & their interrupts
  ide_init();      // disk
  mp_startthem();  // other CPUs
-  if(ismp){
+  if(!ismp)
-    lapic_timerinit();   // smp timer
-    lapic_enableintr();  // local interrupts
-  }else
    pit8253_timerinit(); // uniprocessor timer
  userinit();      // first user process
@@ -74,8 +70,6 @@ mpmain(void)
  cprintf("cpu%d: starting\n", cpu());
  idtinit();
  lapic_init(cpu());
-  lapic_timerinit();
-  lapic_enableintr();
  setupsegs(0);
  cpuid(0, 0, 0, 0, 0);  // memory barrier