ref: 26e00d014cebde8bc07725700b5ac9c0cade8171
dir: /sys/src/cmd/aux/realemu/main.c/
#include <u.h>
#include <libc.h>
#include "dat.h"
#include "fns.h"
/* for fs */
#include <auth.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
#include "/386/include/ureg.h"
enum {
MEMSIZE = 0x100000,
RMBUF = 0x9000,
RMCODE = 0x8000,
PITHZ = 1193182,
PITNS = 1000000000/PITHZ,
};
static Cpu cpu;
static uchar memory[MEMSIZE+4];
static uchar pageregtmp[0x10];
static int portfd[5];
static int realmemfd;
static int cputrace;
static int porttrace;
static Pit pit[3];
static uchar rtcaddr;
static vlong pitclock;
static void
startclock(void)
{
pitclock = nsec();
}
static void
runclock(void)
{
vlong now, dt;
now = nsec();
dt = now - pitclock;
if(dt >= PITNS){
clockpit(pit, dt/PITNS);
pitclock = now;
}
}
static ulong
gw1(uchar *p)
{
return p[0];
}
static ulong
gw2(uchar *p)
{
return (ulong)p[0] | (ulong)p[1]<<8;
}
static ulong
gw4(uchar *p)
{
return (ulong)p[0] | (ulong)p[1]<<8 | (ulong)p[2]<<16 | (ulong)p[3]<<24;
}
static ulong (*gw[5])(uchar *p) = {
[1] gw1,
[2] gw2,
[4] gw4,
};
static void
pw1(uchar *p, ulong w)
{
p[0] = w & 0xFF;
}
static void
pw2(uchar *p, ulong w)
{
p[0] = w & 0xFF;
p[1] = (w>>8) & 0xFF;
}
static void
pw4(uchar *p, ulong w)
{
p[0] = w & 0xFF;
p[1] = (w>>8) & 0xFF;
p[2] = (w>>16) & 0xFF;
p[3] = (w>>24) & 0xFF;
}
static void (*pw[5])(uchar *p, ulong w) = {
[1] pw1,
[2] pw2,
[4] pw4,
};
static ulong
rbad(void *, ulong off, int)
{
fprint(2, "bad mem read %.5lux\n", off);
trap(&cpu, EMEM);
/* not reached */
return 0;
}
static void
wbad(void *, ulong off, ulong, int)
{
fprint(2, "bad mem write %.5lux\n", off);
trap(&cpu, EMEM);
}
static ulong
rmem(void *, ulong off, int len)
{
return gw[len](memory + off);
}
static void
wmem(void *, ulong off, ulong w, int len)
{
pw[len](memory + off, w);
}
static ulong
rrealmem(void *, ulong off, int len)
{
uchar data[4];
if(pread(realmemfd, data, len, off) != len){
fprint(2, "bad real mem read %.5lux: %r\n", off);
trap(&cpu, EMEM);
}
return gw[len](data);
}
static void
wrealmem(void *, ulong off, ulong w, int len)
{
uchar data[4];
pw[len](data, w);
if(pwrite(realmemfd, data, len, off) != len){
fprint(2, "bad real mem write %.5lux: %r\n", off);
trap(&cpu, EMEM);
}
}
static ulong
rport(void *, ulong p, int len)
{
uchar data[4];
ulong w;
switch(p){
case 0x20: /* PIC 1 */
case 0x21:
w = 0;
break;
case 0x40:
case 0x41:
case 0x42:
case 0x43:
runclock();
w = rpit(pit, p - 0x40);
break;
case 0x60: /* keyboard data output buffer */
w = 0;
break;
case 0x61: /* keyboard controller port b */
runclock();
w = pit[2].out<<5 | pit[2].gate;
break;
case 0x62: /* PPI (XT only) */
runclock();
w = pit[2].out<<5;
break;
case 0x63: /* PPI (XT only) read dip switches */
w = 0;
break;
case 0x65: /* A20 gate */
w = 1 << 2;
break;
case 0x70: /* RTC addr */
w = rtcaddr;
break;
case 0x71: /* RTC data */
w = 0xFF;
break;
case 0x80: /* extra dma registers (temp) */
case 0x84:
case 0x85:
case 0x86:
case 0x88:
case 0x8c:
case 0x8d:
case 0x8e:
w = pageregtmp[p-0x80];
break;
case 0x92: /* A20 gate (system control port a) */
w = 1 << 1;
break;
case 0xa0: /* PIC 2 */
case 0xa1:
w = 0;
break;
default:
if(pread(portfd[len], data, len, p) != len){
fprint(2, "bad %d bit port read %.4lux: %r\n", len*8, p);
trap(&cpu, EIO);
}
w = gw[len](data);
}
if(porttrace)
fprint(2, "rport %.4lux %.*lux\n", p, len<<1, w);
return w;
}
static void
wport(void *, ulong p, ulong w, int len)
{
uchar data[4];
if(porttrace)
fprint(2, "wport %.4lux %.*lux\n", p, len<<1, w);
switch(p){
case 0x20: /* PIC 1 */
case 0x21:
break;
case 0x40:
case 0x41:
case 0x42:
case 0x43:
runclock();
wpit(pit, p - 0x40, w);
break;
case 0x60: /* keyboard controller data port */
break;
case 0x61: /* keyboard controller port B */
setgate(&pit[2], w & 1);
break;
case 0x62: /* PPI (XT only) */
case 0x63:
case 0x64: /* KB controller input buffer (ISA, EISA) */
case 0x65: /* A20 gate (bit 2) */
break;
case 0x70: /* RTC addr */
rtcaddr = w & 0xFF;
break;
case 0x71: /* RTC data */
break;
case 0x80:
case 0x84:
case 0x85:
case 0x86:
case 0x88:
case 0x8c:
case 0x8d:
case 0x8e:
pageregtmp[p-0x80] = w & 0xFF;
break;
case 0x92: /* system control port a */
case 0x94: /* system port enable setup register */
case 0x96:
break;
case 0xA0: /* PIC 2 */
case 0xA1:
break;
default:
pw[len](data, w);
if(pwrite(portfd[len], data, len, p) != len){
fprint(2, "bad %d bit port write %.4lux: %r\n", len*8, p);
trap(&cpu, EIO);
}
}
}
static Bus memio[] = {
/* 0 */ memory, rmem, wmem, /* RAM: IVT, BIOS data area */
/* 1 */ memory, rmem, wmem, /* custom */
/* 2 */ nil, rbad, wbad,
/* 3 */ nil, rbad, wbad,
/* 4 */ nil, rbad, wbad,
/* 5 */ nil, rbad, wbad,
/* 6 */ nil, rbad, wbad,
/* 7 */ nil, rbad, wbad,
/* 8 */ nil, rbad, wbad,
/* 9 */ memory, rmem, wmem, /* RAM: extended BIOS data area */
/* A */ nil, rrealmem, wrealmem, /* RAM: VGA framebuffer */
/* B */ nil, rrealmem, wrealmem, /* RAM: VGA framebuffer */
/* C */ memory, rmem, wmem, /* ROM: VGA BIOS */
/* D */ nil, rbad, wbad,
/* E */ memory, rmem, wmem, /* ROM: BIOS */
/* F */ memory, rmem, wbad, /* ROM: BIOS */
};
static Bus portio = {
nil, rport, wport,
};
static void
cpuinit(void)
{
int i;
fmtinstall('I', instfmt);
fmtinstall('J', flagfmt);
fmtinstall('C', cpufmt);
if((portfd[1] = open("#P/iob", ORDWR)) < 0)
sysfatal("open iob: %r");
if((portfd[2] = open("#P/iow", ORDWR)) < 0)
sysfatal("open iow: %r");
if((portfd[4] = open("#P/iol", ORDWR)) < 0)
sysfatal("open iol: %r");
if((realmemfd = open("#P/realmodemem", ORDWR)) < 0)
sysfatal("open realmodemem: %r");
for(i=0; i<nelem(memio); i++){
ulong off;
if(memio[i].r != rmem)
continue;
off = (ulong)i << 16;
seek(realmemfd, off, 0);
if(readn(realmemfd, memory + off, 0x10000) != 0x10000)
sysfatal("read real mem %lux: %r\n", off);
}
cpu.ic = 0;
cpu.mem = memio;
cpu.port = &portio;
cpu.alen = cpu.olen = cpu.slen = 2;
}
static char Ebusy[] = "device is busy";
static char Eintr[] = "interrupted";
static char Eperm[] = "permission denied";
static char Eio[] = "i/o error";
static char Emem[] = "bad memory access";
static char Enonexist[] = "file does not exist";
static char Ebadspec[] = "bad attach specifier";
static char Ewalk[] = "walk in non directory";
static char Ebadureg[] = "write a Ureg";
static char Ebadoff[] = "invalid offset";
static char Ebadtrap[] = "bad trap";
static char *trapstr[] = {
[EDIV0] "division by zero",
[EDEBUG] "debug exception",
[ENMI] "not maskable interrupt",
[EBRK] "breakpoint",
[EINTO] "into overflow",
[EBOUND] "bounds check",
[EBADOP] "bad opcode",
[ENOFPU] "no fpu installed",
[EDBLF] "double fault",
[EFPUSEG] "fpu segment overflow",
[EBADTSS] "invalid task state segment",
[ENP] "segment not present",
[ESTACK] "stack fault",
[EGPF] "general protection fault",
[EPF] "page fault",
};
static int flushed(void *);
#define GETUREG(x) gw[sizeof(u->x)]((uchar*)&u->x)
#define PUTUREG(x,y) pw[sizeof(u->x)]((uchar*)&u->x,y)
static char*
realmode(Cpu *cpu, struct Ureg *u, void *r)
{
char *err;
int i;
cpu->reg[RDI] = GETUREG(di);
cpu->reg[RSI] = GETUREG(si);
cpu->reg[RBP] = GETUREG(bp);
cpu->reg[RBX] = GETUREG(bx);
cpu->reg[RDX] = GETUREG(dx);
cpu->reg[RCX] = GETUREG(cx);
cpu->reg[RAX] = GETUREG(ax);
cpu->reg[RGS] = GETUREG(gs);
cpu->reg[RFS] = GETUREG(fs);
cpu->reg[RES] = GETUREG(es);
cpu->reg[RDS] = GETUREG(ds);
cpu->reg[RFL] = GETUREG(flags);
if(i = GETUREG(trap)){
cpu->reg[RSS] = 0x0000;
cpu->reg[RSP] = 0x7C00;
cpu->reg[RCS] = (RMCODE>>4)&0xF000;
cpu->reg[RIP] = RMCODE & 0xFFFF;
memory[RMCODE] = 0xf4; /* HLT instruction */
if(intr(cpu, i) < 0)
return Ebadtrap;
} else {
cpu->reg[RSS] = GETUREG(ss);
cpu->reg[RSP] = GETUREG(sp);
cpu->reg[RCS] = GETUREG(cs);
cpu->reg[RIP] = GETUREG(pc);
}
startclock();
for(;;){
if(cputrace)
fprint(2, "%C\n", cpu);
switch(i = xec(cpu, (porttrace | cputrace) ? 1 : 100000)){
case -1:
if(flushed(r)){
err = Eintr;
break;
}
runclock();
continue;
/* normal interrupts */
default:
if(intr(cpu, i) < 0){
err = Ebadtrap;
break;
}
continue;
/* pseudo-interrupts */
case EHALT:
err = nil;
break;
case EIO:
err = Eio;
break;
case EMEM:
err = Emem;
break;
/* processor traps */
case EDIV0:
case EDEBUG:
case ENMI:
case EBRK:
case EINTO:
case EBOUND:
case EBADOP:
case ENOFPU:
case EDBLF:
case EFPUSEG:
case EBADTSS:
case ENP:
case ESTACK:
case EGPF:
case EPF:
PUTUREG(trap, i);
err = trapstr[i];
break;
}
break;
}
if(err)
fprint(2, "%s\n%C\n", err, cpu);
PUTUREG(di, cpu->reg[RDI]);
PUTUREG(si, cpu->reg[RSI]);
PUTUREG(bp, cpu->reg[RBP]);
PUTUREG(bx, cpu->reg[RBX]);
PUTUREG(dx, cpu->reg[RDX]);
PUTUREG(cx, cpu->reg[RCX]);
PUTUREG(ax, cpu->reg[RAX]);
PUTUREG(gs, cpu->reg[RGS]);
PUTUREG(fs, cpu->reg[RFS]);
PUTUREG(es, cpu->reg[RES]);
PUTUREG(ds, cpu->reg[RDS]);
PUTUREG(flags, cpu->reg[RFL]);
PUTUREG(pc, cpu->reg[RIP]);
PUTUREG(cs, cpu->reg[RCS]);
PUTUREG(sp, cpu->reg[RSP]);
PUTUREG(ss, cpu->reg[RSS]);
return err;
}
enum {
Qroot,
Qcall,
Qmem,
Nqid,
};
static struct Qtab {
char *name;
int mode;
int type;
int length;
} qtab[Nqid] = {
"/",
DMDIR|0555,
QTDIR,
0,
"realmode",
0666,
0,
0,
"realmodemem",
0666,
0,
MEMSIZE,
};
static int
fillstat(ulong qid, Dir *d)
{
struct Qtab *t;
memset(d, 0, sizeof(Dir));
d->uid = "realemu";
d->gid = "realemu";
d->muid = "";
d->qid = (Qid){qid, 0, 0};
d->atime = time(0);
t = qtab + qid;
d->name = t->name;
d->qid.type = t->type;
d->mode = t->mode;
d->length = t->length;
return 1;
}
static void
fsattach(Req *r)
{
char *spec;
spec = r->ifcall.aname;
if(spec && spec[0]){
respond(r, Ebadspec);
return;
}
r->fid->qid = (Qid){Qroot, 0, QTDIR};
r->ofcall.qid = r->fid->qid;
respond(r, nil);
}
static void
fsstat(Req *r)
{
fillstat((ulong)r->fid->qid.path, &r->d);
r->d.name = estrdup9p(r->d.name);
r->d.uid = estrdup9p(r->d.uid);
r->d.gid = estrdup9p(r->d.gid);
r->d.muid = estrdup9p(r->d.muid);
respond(r, nil);
}
static char*
fswalk1(Fid *fid, char *name, Qid *qid)
{
int i;
ulong path;
path = fid->qid.path;
switch(path){
case Qroot:
if (strcmp(name, "..") == 0) {
*qid = (Qid){Qroot, 0, QTDIR};
fid->qid = *qid;
return nil;
}
for(i = fid->qid.path; i<Nqid; i++){
if(strcmp(name, qtab[i].name) != 0)
continue;
*qid = (Qid){i, 0, 0};
fid->qid = *qid;
return nil;
}
return Enonexist;
default:
return Ewalk;
}
}
static void
fsopen(Req *r)
{
static int need[4] = { 4, 2, 6, 1 };
struct Qtab *t;
int n;
t = qtab + r->fid->qid.path;
n = need[r->ifcall.mode & 3];
if((n & t->mode) != n)
respond(r, Eperm);
else
respond(r, nil);
}
static int
readtopdir(Fid*, uchar *buf, long off, int cnt, int blen)
{
int i, m, n;
long pos;
Dir d;
n = 0;
pos = 0;
for (i = 1; i < Nqid; i++){
fillstat(i, &d);
m = convD2M(&d, &buf[n], blen-n);
if(off <= pos){
if(m <= BIT16SZ || m > cnt)
break;
n += m;
cnt -= m;
}
pos += m;
}
return n;
}
static Channel *reqchan;
static void
cpuproc(void *)
{
static struct Ureg rmu;
ulong path;
vlong o;
ulong n;
char *p;
Req *r;
threadsetname("cpuproc");
while(r = recvp(reqchan)){
if(flushed(r)){
respond(r, Eintr);
continue;
}
path = r->fid->qid.path;
p = r->ifcall.data;
n = r->ifcall.count;
o = r->ifcall.offset;
switch(((int)r->ifcall.type<<8)|path){
case (Tread<<8) | Qmem:
readbuf(r, memory, MEMSIZE);
respond(r, nil);
break;
case (Tread<<8) | Qcall:
readbuf(r, &rmu, sizeof rmu);
respond(r, nil);
break;
case (Twrite<<8) | Qmem:
if(o < 0 || o >= MEMSIZE || o+n > MEMSIZE){
respond(r, Ebadoff);
break;
}
memmove(memory + o, p, n);
r->ofcall.count = n;
respond(r, nil);
break;
case (Twrite<<8) | Qcall:
if(n != sizeof rmu){
respond(r, Ebadureg);
break;
}
memmove(&rmu, p, n);
if(p = realmode(&cpu, &rmu, r)){
respond(r, p);
break;
}
r->ofcall.count = n;
respond(r, nil);
break;
}
}
}
static Channel *flushchan;
static int
flushed(void *r)
{
return nbrecvp(flushchan) == r;
}
static void
fsflush(Req *r)
{
nbsendp(flushchan, r->oldreq);
respond(r, nil);
}
static void
dispatch(Req *r)
{
if(!nbsendp(reqchan, r))
respond(r, Ebusy);
}
static void
fsread(Req *r)
{
switch((ulong)r->fid->qid.path){
case Qroot:
r->ofcall.count = readtopdir(r->fid, (void*)r->ofcall.data, r->ifcall.offset,
r->ifcall.count, r->ifcall.count);
respond(r, nil);
break;
default:
dispatch(r);
}
}
static void
fsend(Srv*)
{
threadexitsall(nil);
}
static Srv fs = {
.attach= fsattach,
.walk1= fswalk1,
.open= fsopen,
.read= fsread,
.write= dispatch,
.stat= fsstat,
.flush= fsflush,
.end= fsend,
};
static void
usage(void)
{
fprint(2, "usgae:\t%s [-Dpt] [-s srvname] [-m mountpoint]\n", argv0);
exits("usage");
}
void
threadmain(int argc, char *argv[])
{
char *mnt = "/dev";
char *srv = nil;
ARGBEGIN{
case 'D':
chatty9p++;
break;
case 'p':
porttrace = 1;
break;
case 't':
cputrace = 1;
break;
case 's':
srv = EARGF(usage());
mnt = nil;
break;
case 'm':
mnt = EARGF(usage());
break;
default:
usage();
}ARGEND
cpuinit();
reqchan = chancreate(sizeof(Req*), 8);
flushchan = chancreate(sizeof(Req*), 8);
procrfork(cpuproc, nil, 16*1024, RFNAMEG|RFNOTEG);
threadpostmountsrv(&fs, srv, mnt, MBEFORE);
}