ref: e81c54ba2ecc673a4d5f8aed0e9b52841fe07b0d
dir: /os/ks32/trap.c/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "ureg.h"
#include "../port/error.h"
#define waslo(sr) (!((sr) & (PsrDirq|PsrDfiq)))
typedef struct IrqEntry {
void (*r)(Ureg*, void*);
void *a;
int v;
} IrqEntry;
enum {
NumIRQbits = MaxIRQbit+1,
};
static IrqEntry Irq[NumIRQbits];
Instr BREAK = 0xE6BAD010;
int (*breakhandler)(Ureg*, Proc*);
int (*catchdbg)(Ureg *, uint);
void dumperrstk(void);
/*
* Interrupt sources not masked by splhi() -- these are special
* interrupt handlers (e.g. profiler or watchdog), not allowed
* to share regular kernel data structures. All interrupts are
* masked by splfhi(), which should only be used herein.
*/
int splfhi(void); /* disable all */
int splflo(void); /* enable FIQ */
static int actIrq = -1; /* Active Irq handler, 0-31, or -1 if none */
static int wasIrq = -1; /* Interrupted Irq handler */
static Proc *iup; /* Interrupted kproc */
void
intrmask(int v, int tbdf)
{
USED(tbdf);
if(v < 0 || v > MaxIRQbit)
panic("intrmask: irq source %d out of range\n", v);
INTREG->msk |= (1 << v);
}
void
intrunmask(int v, int tbdf)
{
USED(tbdf);
if(v < 0 || v > MaxIRQbit)
panic("intrunmask: irq source %d out of range\n", v);
INTREG->msk &= ~(1 << v);
}
void
intrclear(int v, int tbdf)
{
USED(tbdf);
if(v < 0 || v > MaxIRQbit)
panic("intrclear: irq source %d out of range\n", v);
INTREG->pnd = (1 << v);
}
void
intrenable(int v, void (*f)(Ureg*, void*), void* a, int tbdf)
{
int x;
USED(tbdf);
if(v < 0 || v > MaxIRQbit)
panic("intrenable: irq source %d out of range\n", v);
Irq[v].r = f;
Irq[v].a = a;
x = splfhi();
/* Enable the interrupt by clearing the mask bit */
INTREG->msk &= ~(1 << v);
splx(x);
}
ulong fiqstack[4];
ulong irqstack[4];
ulong abtstack[4];
ulong undstack[4];
static void
safeintr(Ureg *, void *a)
{
int v = (int)a;
int x;
/* No handler - clear the mask so we don't loop */
x = splfhi();
intrmask(v, 0);
splx(x);
iprint("SPURIOUS INTERRUPT %d\n", v);
}
static void
trapv(int off, void (*f)(void))
{
ulong *vloc;
int offset;
vloc = (ulong *)off;
offset = (((ulong *) f) - vloc)-2;
*vloc = (0xea << 24) | offset;
}
static void
maskallints(void)
{
INTREG->msk = 0x3fffff; /* mask out all interrupts */
}
void
trapinit(void)
{
int v;
IntReg *intr = INTREG;
intr->mod = 0; /* all interrupts to be done in IRQ mode */
/* set up stacks for various exceptions */
setr13(PsrMfiq, fiqstack+nelem(fiqstack));
setr13(PsrMirq, irqstack+nelem(irqstack));
setr13(PsrMabt, abtstack+nelem(abtstack));
setr13(PsrMund, undstack+nelem(undstack));
for (v = 0; v < nelem(Irq); v++) {
Irq[v].r = safeintr;
Irq[v].a = (void *)v;
Irq[v].v = v;
}
trapv(0x0, _vsvccall);
trapv(0x4, _vundcall);
trapv(0xc, _vpabcall);
trapv(0x10, _vdabcall);
trapv(0x18, _virqcall);
trapv(0x1c, _vfiqcall);
trapv(0x8, _vsvccall);
serwrite = uartputs;
}
static char *_trap_str[PsrMask+1] = {
[ PsrMfiq ] "Fiq interrupt",
[ PsrMirq ] "Mirq interrupt",
[ PsrMsvc ] "SVC/SWI Exception",
[ PsrMabt ] "Prefetch Abort/Data Abort",
[ PsrMabt+1 ] "Data Abort",
[ PsrMund ] "Undefined instruction",
[ PsrMsys ] "Sys trap"
};
static char *
trap_str(int psr)
{
char *str = _trap_str[psr & PsrMask];
if (!str)
str = "Undefined trap";
return(str);
}
static void
sys_trap_error(int type)
{
char errbuf[ERRMAX];
sprint(errbuf, "sys: trap: %s\n", trap_str(type));
error(errbuf);
}
void
dflt(Ureg *ureg, ulong far)
{
char buf[ERRMAX];
dumpregs(ureg);
sprint(buf, "trap: fault pc=%8.8lux addr=0x%lux", (ulong)ureg->pc, far);
disfault(ureg, buf);
}
/*
* All traps come here. It is slower to have all traps ca)
* rather than directly vectoring the handler.
* However, this avoids
* a lot of code dup and possible bugs.
* trap is called splfhi().
*/
void
trap(Ureg* ureg)
{
//
// This is here to make sure that a clock interrupt doesn't
// cause the process we just returned into to get scheduled
// before it single stepped to the next instruction.
//
static struct {int callsched;} c = {1};
int itype;
/*
* All interrupts/exceptions should be resumed at ureg->pc-4,
* except for Data Abort which resumes at ureg->pc-8.
*/
itype = ureg->type;
if(itype == PsrMabt+1)
ureg->pc -= 8;
else
ureg->pc -= 4;
ureg->sp = (ulong)(ureg+1);
if (itype == PsrMirq || itype == PsrMfiq) { /* Interrupt Request */
Proc *saveup;
int t;
SET(t);
SET(saveup);
if (itype == PsrMirq) {
splflo(); /* Allow nonmasked interrupts */
if (saveup = up) {
t = m->ticks; /* CPU time per proc */
saveup->pc = ureg->pc; /* debug info */
saveup->dbgreg = ureg;
}
} else {
/* for profiler(wasbusy()): */
wasIrq = actIrq; /* Save ID of interrupted handler */
iup = up; /* Save ID of interrupted proc */
}
while (1) { /* Use up all the active interrupts */
ulong hpip;
IrqEntry *curIrq;
IntReg *intr = INTREG;
hpip = itype == PsrMirq ? intr->oset_irq : intr->oset_fiq;
if (hpip == 0x54)
break;
curIrq = Irq + (hpip >> 2);
actIrq = curIrq->v; /* show active interrupt handler */
up = 0; /* Make interrupted process invisible */
curIrq->r(ureg, curIrq->a); /* Call handler */
}
if (itype == PsrMirq) {
up = saveup; /* Make interrupted process visible */
actIrq = -1; /* No more interrupt handler running */
preemption(m->ticks - t);
saveup->dbgreg = nil;
} else {
actIrq = wasIrq;
up = iup;
}
return;
}
setled7ascii('E');
/* All other traps */
if (ureg->psr & PsrDfiq)
goto faultpanic;
if (up)
up->dbgreg = ureg;
// setled7ascii('0' + itype);
switch(itype) {
case PsrMund: /* Undefined instruction */
if(*(ulong*)ureg->pc == BREAK && breakhandler) {
int s;
Proc *p;
p = up;
/* if (!waslo(ureg->psr) || (ureg->pc >= (ulong)splhi && ureg->pc < (ulong)islo))
p = 0; */
s = breakhandler(ureg, p);
if(s == BrkSched) {
c.callsched = 1;
sched();
} else if(s == BrkNoSched) {
c.callsched = 0;
if(up)
up->dbgreg = 0;
return;
}
break;
}
if (!up)
goto faultpanic;
spllo();
if (waserror()) {
if(waslo(ureg->psr) && (up->type == Interp))
disfault(ureg, up->env->errstr);
setpanic();
dumpregs(ureg);
panic("%s", up->env->errstr);
}
if (!fpiarm(ureg)) {
dumpregs(ureg);
sys_trap_error(ureg->type);
}
poperror();
break;
case PsrMsvc: /* Jump through 0 or SWI */
if (waslo(ureg->psr) && up && (up->type == Interp)) {
spllo();
dumpregs(ureg);
sys_trap_error(ureg->type);
}
goto faultpanic;
case PsrMabt: /* Prefetch abort */
if (catchdbg && catchdbg(ureg, 0))
break;
ureg->pc -= 4;
case PsrMabt+1: { /* Data abort */
if (waslo(ureg->psr) && up && (up->type == Interp)) {
spllo();
dflt(ureg, 0);
}
goto faultpanic;
}
default: /* ??? */
faultpanic:
setpanic();
dumpregs(ureg);
panic("exception %uX %s\n", ureg->type, trap_str(ureg->type));
break;
}
splhi();
if(up)
up->dbgreg = 0; /* becomes invalid after return from trap */
}
void
setpanic(void)
{
extern void screenon(int);
extern int consoleprint;
if (breakhandler != 0) /* don't mess up debugger */
return;
maskallints();
// spllo();
/* screenon(!consoleprint); */
consoleprint = 1;
serwrite = uartputs;
}
int
isvalid_wa(void *v)
{
return((ulong)v >= 0x8000 && (ulong)v < conf.topofmem && !((ulong)v & 3));
}
int
isvalid_va(void *v)
{
return((ulong)v >= 0x8000 && (ulong)v < conf.topofmem);
}
void
dumplongs(char *msg, ulong *v, int n)
{
int ii;
int ll;
ll = print("%s at %ulx: ", msg, v);
for (ii = 0; ii < n; ii++)
{
if (ll >= 60)
{
print("\n");
ll = print(" %ulx: ", v);
}
if (isvalid_va(v))
ll += print(" %ulx", *v++);
else
{
ll += print(" invalid");
break;
}
}
print("\n");
USED(ll);
}
void
dumpregs(Ureg* ureg)
{
Proc *p;
print("TRAP: %s", trap_str(ureg->type));
if ((ureg->psr & PsrMask) != PsrMsvc)
print(" in %s", trap_str(ureg->psr));
/*
if ((ureg->type == PsrMabt) || (ureg->type == PsrMabt + 1))
print(" FSR %8.8luX FAR %8.8luX\n", mmuregr(CpFSR), mmuregr(CpFAR));
*/
print("\n");
print("PSR %8.8uX type %2.2uX PC %8.8uX LINK %8.8uX\n",
ureg->psr, ureg->type, ureg->pc, ureg->link);
print("R14 %8.8uX R13 %8.8uX R12 %8.8uX R11 %8.8uX R10 %8.8uX\n",
ureg->r14, ureg->r13, ureg->r12, ureg->r11, ureg->r10);
print("R9 %8.8uX R8 %8.8uX R7 %8.8uX R6 %8.8uX R5 %8.8uX\n",
ureg->r9, ureg->r8, ureg->r7, ureg->r6, ureg->r5);
print("R4 %8.8uX R3 %8.8uX R2 %8.8uX R1 %8.8uX R0 %8.8uX\n",
ureg->r4, ureg->r3, ureg->r2, ureg->r1, ureg->r0);
print("Stack is at: %8.8luX\n",ureg);
print("CPSR %8.8uX SPSR %8.8uX ", cpsrr(), spsrr());
print("PC %8.8lux LINK %8.8lux\n", (ulong)ureg->pc, (ulong)ureg->link);
p = (actIrq >= 0) ? iup : up;
if (p != nil)
print("Process stack: %lux-%lux\n",
p->kstack, p->kstack+KSTACK-4);
else
print("System stack: %lux-%lux\n",
(ulong)(m+1), (ulong)m+KSTACK-4);
dumplongs("stk", (ulong *)(ureg + 1), 16);
print("bl's: ");
dumpstk((ulong *)(ureg + 1));
if (isvalid_wa((void *)ureg->pc))
dumplongs("code", (ulong *)ureg->pc - 5, 12);
dumperrstk();
/* for(;;) ; */
}
void
dumpstack(void)
{
ulong l;
if (breakhandler != 0)
dumpstk(&l);
}
void
dumpstk(ulong *l)
{
ulong *v, i;
ulong inst;
ulong *estk;
uint len;
len = KSTACK/sizeof *l;
if (up == 0)
len -= l - (ulong *)m;
else
len -= l - (ulong *)up->kstack;
if (len > KSTACK/sizeof *l)
len = KSTACK/sizeof *l;
else if (len < 0)
len = 50;
i = 0;
for(estk = l + len; l<estk; l++) {
if (!isvalid_wa(l)) {
i += print("invalid(%lux)", l);
break;
}
v = (ulong *)*l;
if (isvalid_wa(v)) {
inst = *(v - 1);
if ( (
((inst & 0x0ff0f000) == 0x0280f000)
&&
((*(v-2) & 0x0ffff000) == 0x028fe000)
)
||
((inst & 0x0f000000) == 0x0b000000)
) {
i += print("%8.8lux ", v);
}
}
if (i >= 60) {
print("\n");
i = print(" ");
}
}
if (i)
print("\n");
}
void
dumperrstk(void)
{
int ii, ll;
if (!up)
return;
ll = print("err stk: ");
for (ii = 0; ii < NERR; ii++) {
if (ii == up->nerrlab)
ll += print("* ");
if (up->errlab[ii].pc) {
ll += print(" %lux/%8.8lux",
up->errlab[ii].sp, up->errlab[ii].pc);
if (ll >= 60) {
print("\n");
ll = 0;
}
}
}
if (ll)
print("\n");
}
void
trapspecial(int (*f)(Ureg *, uint))
{
catchdbg = f;
}