ref: 5e010fd8a82ec3b6552b4002bcd4be0586081e9a
dir: /sys/src/9/pc/irq.c/
#include "u.h"
#include "tos.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "ureg.h"
#include "../port/error.h"
static Lock vctllock;
static Vctl *vclock, *vctl[256];
enum
{
Ntimevec = 20 /* number of time buckets for each intr */
};
ulong intrtimes[256][Ntimevec];
/*
* keep histogram of interrupt service times
*/
static void
intrtime(Mach*, int vno)
{
ulong diff;
ulong x;
x = perfticks();
diff = x - m->perf.intrts;
m->perf.intrts = x;
m->perf.inintr += diff;
if(up == nil && m->perf.inidle > diff)
m->perf.inidle -= diff;
diff /= m->cpumhz*100; /* quantum = 100µsec */
if(diff >= Ntimevec)
diff = Ntimevec-1;
intrtimes[vno][diff]++;
}
int
irqhandled(Ureg *ureg, int vno)
{
Vctl *ctl, *v;
int i;
ctl = vctl[vno];
if(ctl != nil){
if(vno < VectorPIC){
(*ctl->f)(ureg, ctl->a);
return 1;
}
m->perf.intrts = perfticks();
m->intr++;
m->lastintr = ctl->irq;
if(ctl->isr != nil)
(*ctl->isr)(vno);
for(v = ctl; v != nil; v = v->next)
(*v->f)(ureg, v->a);
if(ctl->eoi != nil)
(*ctl->eoi)(vno);
intrtime(m, vno);
preempted(ctl == vclock);
return 1;
}
if(vno < VectorPIC || vno == VectorSYSCALL)
return 0;
m->spuriousintr++;
if(arch->intrspurious != nil && (*arch->intrspurious)(vno) == 0)
return 1; /* false alarm */
iprint("cpu%d: spurious interrupt %d, last %d\n",
m->machno, vno, m->lastintr);
/* call all non-local interrupt routines, just in case */
for(i = VectorPIC; i < nelem(vctl); i++){
ctl = vctl[i];
if(ctl == nil || ctl == vclock || ctl->local)
continue;
for(v = ctl; v != nil; v = v->next)
(*v->f)(ureg, v->a);
}
return -1;
}
void
trapenable(int vno, void (*f)(Ureg*, void*), void* a, char *name)
{
Vctl *v;
if(f == nil){
print("trapenable: nil handler for %d, for %s\n",
vno, name);
return;
}
if(vno < 0 || vno >= VectorPIC){
print("trapenable: vno %d out of range", vno);
return;
}
if((v = xalloc(sizeof(Vctl))) == nil)
panic("trapenable: out of memory");
v->f = f;
v->a = a;
v->tbdf = BUSUNKNOWN;
v->irq = -1;
v->vno = vno;
v->cpu = -1;
strncpy(v->name, name, KNAMELEN-1);
v->name[KNAMELEN-1] = 0;
ilock(&vctllock);
if(vctl[vno] != nil){
print("trapenable: vno %d assigned twice: %s %s\n",
vno, vctl[vno]->name, v->name);
iunlock(&vctllock);
xfree(v);
return;
}
vctl[vno] = v;
iunlock(&vctllock);
}
static Vctl*
delayfree(Vctl *v)
{
static Vctl *q[4];
static uint x;
Vctl *r;
r = q[x], q[x] = v;
x = (x+1) % nelem(q);
return r;
}
void
intrenable(int irq, void (*f)(Ureg*, void*), void* a, int tbdf, char *name)
{
Vctl **pv, *v;
if(f == nil){
print("intrenable: nil handler for %d, tbdf 0x%uX for %s\n",
irq, tbdf, name);
return;
}
if(arch->intrirqno != nil)
irq = (*arch->intrirqno)(irq, tbdf);
if((v = xalloc(sizeof(Vctl))) == nil)
panic("intrenable: out of memory");
v->f = f;
v->a = a;
v->tbdf = tbdf;
v->irq = irq;
v->vno = -1;
v->cpu = -1;
strncpy(v->name, name, KNAMELEN-1);
v->name[KNAMELEN-1] = 0;
ilock(&vctllock);
v->vno = (*arch->intrassign)(v);
if(v->vno < VectorPIC || v->vno >= nelem(vctl)){
print("intrenable: couldn't assign irq %d, tbdf 0x%uX for %s\n",
irq, tbdf, v->name);
Unlockandfree:
iunlock(&vctllock);
if(v != nil)
xfree(v);
return;
}
pv = &vctl[v->vno];
if(*pv != nil){
if((*pv)->isr != v->isr || (*pv)->eoi != v->eoi){
print("intrenable: incompatible handler: %s %s %#p %#p %#p %#p\n",
(*pv)->name, v->name,
(*pv)->isr, v->isr,
(*pv)->eoi, v->eoi);
goto Unlockandfree;
}
if(*pv == vclock)
pv = &vclock->next;
v->next = *pv;
}
if(strcmp(name, "clock") == 0)
vclock = v;
*pv = v;
if(v->enable != nil){
coherence();
if((*v->enable)(v, pv != &vctl[v->vno] || v->next != nil) < 0){
print("intrenable: couldn't enable irq %d, tbdf 0x%uX for %s\n",
irq, tbdf, v->name);
*pv = v->next;
if(v == vclock)
vclock = nil;
if(conf.nmach > 1)
v = delayfree(v);
goto Unlockandfree;
}
}
iunlock(&vctllock);
}
void
intrdisable(int irq, void (*f)(Ureg *, void *), void *a, int tbdf, char *name)
{
Vctl **pv, *v;
int vno;
if(arch->intrirqno != nil)
irq = (*arch->intrirqno)(irq, tbdf);
if(irq != -1 && arch->intrvecno != nil) {
vno = (*arch->intrvecno)(irq);
if(vno < VectorPIC || vno >= nelem(vctl)){
irq = -1;
vno = VectorPIC;
}
} else {
irq = -1;
vno = VectorPIC;
}
ilock(&vctllock);
do {
for(pv = &vctl[vno]; (v = *pv) != nil; pv = &v->next){
if((v->irq == irq || irq == -1)
&& v->tbdf == tbdf && v->f == f && v->a == a
&& strcmp(v->name, name) == 0)
break;
}
if(v != nil){
if(v->disable != nil){
if((*v->disable)(v, pv != &vctl[vno] || v->next != nil) < 0){
print("intrdisable: couldn't disable irq %d, tbdf 0x%uX for %s\n",
irq, tbdf, name);
}
coherence();
}
*pv = v->next;
if(v == vclock)
vclock = nil;
if(conf.nmach > 1)
v = delayfree(v);
iunlock(&vctllock);
if(v != nil)
xfree(v);
return;
}
} while(irq == -1 && ++vno < nelem(vctl));
iunlock(&vctllock);
}
static long
irqallocread(Chan*, void *a, long n, vlong offset)
{
char buf[2*(11+1)+KNAMELEN+1+1];
int vno, m;
Vctl *v;
if(n < 0 || offset < 0)
error(Ebadarg);
for(vno = 0; vno < nelem(vctl); vno++){
for(v = vctl[vno]; v != nil; v = v->next){
m = snprint(buf, sizeof(buf), "%11d %11d %.*s\n", vno, v->irq, KNAMELEN, v->name);
offset -= m;
if(offset >= 0)
continue;
if(n > -offset)
n = -offset;
offset += m;
memmove(a, buf+offset, n);
return n;
}
}
return 0;
}
void
irqinit(void)
{
addarchfile("irqalloc", 0444, irqallocread, nil);
}