ref: 4308f6e7e6586e3a27aa46c4d54c434b8533b16d
dir: /sys/src/9/mtx/devarch.c/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "../port/error.h"
typedef struct IOMap IOMap;
struct IOMap
{
IOMap *next;
char tag[13];
ulong start;
ulong end;
};
static struct
{
Lock;
IOMap *m;
IOMap *free;
IOMap maps[32]; // some initial free maps
QLock ql; // lock for reading map
} iomap;
enum {
Qdir = 0,
Qioalloc = 1,
Qiob,
Qiow,
Qiol,
Qbase,
Qmax = 16,
};
typedef long Rdwrfn(Chan*, void*, long, vlong);
static Rdwrfn *readfn[Qmax];
static Rdwrfn *writefn[Qmax];
static Dirtab archdir[] = {
".", { Qdir, 0, QTDIR }, 0, 0555,
"ioalloc", { Qioalloc, 0 }, 0, 0444,
"iob", { Qiob, 0 }, 0, 0660,
"iow", { Qiow, 0 }, 0, 0660,
"iol", { Qiol, 0 }, 0, 0660,
};
Lock archwlock; /* the lock is only for changing archdir */
int narchdir = Qbase;
int (*_pcmspecial)(char *, ISAConf *);
void (*_pcmspecialclose)(int);
/*
* Add a file to the #P listing. Once added, you can't delete it.
* You can't add a file with the same name as one already there,
* and you get a pointer to the Dirtab entry so you can do things
* like change the Qid version. Changing the Qid path is disallowed.
*/
Dirtab*
addarchfile(char *name, int perm, Rdwrfn *rdfn, Rdwrfn *wrfn)
{
int i;
Dirtab d;
Dirtab *dp;
memset(&d, 0, sizeof d);
strcpy(d.name, name);
d.perm = perm;
lock(&archwlock);
if(narchdir >= Qmax){
unlock(&archwlock);
return nil;
}
for(i=0; i<narchdir; i++)
if(strcmp(archdir[i].name, name) == 0){
unlock(&archwlock);
return nil;
}
d.qid.path = narchdir;
archdir[narchdir] = d;
readfn[narchdir] = rdfn;
writefn[narchdir] = wrfn;
dp = &archdir[narchdir++];
unlock(&archwlock);
return dp;
}
void
ioinit(void)
{
int i;
for(i = 0; i < nelem(iomap.maps)-1; i++)
iomap.maps[i].next = &iomap.maps[i+1];
iomap.maps[i].next = nil;
iomap.free = iomap.maps;
// a dummy entry at 2^17
ioalloc(0x20000, 1, 0, "dummy");
}
//
// alloc some io port space and remember who it was
// alloced to. if port < 0, find a free region.
//
int
ioalloc(int port, int size, int align, char *tag)
{
IOMap *m, **l;
int i;
lock(&iomap);
if(port < 0){
// find a free port above 0x400 and below 0x1000
port = 0x400;
for(l = &iomap.m; *l; l = &(*l)->next){
m = *l;
i = m->start - port;
if(i > size)
break;
if(align > 0)
port = ((port+align-1)/align)*align;
else
port = m->end;
}
if(*l == nil){
unlock(&iomap);
return -1;
}
} else {
// see if the space clashes with previously allocated ports
for(l = &iomap.m; *l; l = &(*l)->next){
m = *l;
if(m->end <= port)
continue;
if(m->start >= port+size)
break;
unlock(&iomap);
return -1;
}
}
m = iomap.free;
if(m == nil){
print("ioalloc: out of maps");
unlock(&iomap);
return port;
}
iomap.free = m->next;
m->next = *l;
m->start = port;
m->end = port + size;
strncpy(m->tag, tag, sizeof(m->tag));
m->tag[sizeof(m->tag)-1] = 0;
*l = m;
archdir[0].qid.vers++;
unlock(&iomap);
return m->start;
}
void
iofree(int port)
{
IOMap *m, **l;
lock(&iomap);
for(l = &iomap.m; *l; l = &(*l)->next){
if((*l)->start == port){
m = *l;
*l = m->next;
m->next = iomap.free;
iomap.free = m;
break;
}
if((*l)->start > port)
break;
}
archdir[0].qid.vers++;
unlock(&iomap);
}
int
iounused(int start, int end)
{
IOMap *m;
for(m = iomap.m; m; m = m->next){
if(start >= m->start && start < m->end
|| start <= m->start && end > m->start)
return 0;
}
return 1;
}
static void
checkport(int start, int end)
{
/* standard vga regs are OK */
if(start >= 0x2b0 && end <= 0x2df+1)
return;
if(start >= 0x3c0 && end <= 0x3da+1)
return;
if(iounused(start, end))
return;
error(Eperm);
}
static Chan*
archattach(char* spec)
{
return devattach('P', spec);
}
Walkqid*
archwalk(Chan* c, Chan *nc, char** name, int nname)
{
return devwalk(c, nc, name, nname, archdir, narchdir, devgen);
}
static int
archstat(Chan* c, uchar* dp, int n)
{
return devstat(c, dp, n, archdir, narchdir, devgen);
}
static Chan*
archopen(Chan* c, int omode)
{
return devopen(c, omode, archdir, nelem(archdir), devgen);
}
static void
archclose(Chan*)
{
}
enum
{
Linelen= 31,
};
static long
archread(Chan *c, void *a, long n, vlong offset)
{
char buf[Linelen+1], *p;
int port;
ushort *sp;
ulong *lp;
IOMap *m;
Rdwrfn *fn;
switch((ulong)c->qid.path){
case Qdir:
return devdirread(c, a, n, archdir, nelem(archdir), devgen);
case Qiob:
port = offset;
checkport(offset, offset+n);
for(p = a; port < offset+n; port++)
*p++ = inb(port);
return n;
case Qiow:
if((n & 0x01) || (offset & 0x01))
error(Ebadarg);
checkport(offset, offset+n+1);
n /= 2;
sp = a;
for(port = offset; port < offset+n; port += 2)
*sp++ = ins(port);
return n*2;
case Qiol:
if((n & 0x03) || (offset & 0x03))
error(Ebadarg);
checkport(offset, offset+n+3);
n /= 4;
lp = a;
for(port = offset; port < offset+n; port += 4)
*lp++ = inl(port);
return n*4;
case Qioalloc:
break;
default:
if(c->qid.path < narchdir && (fn = readfn[c->qid.path]))
return fn(c, a, n, offset);
error(Eperm);
break;
}
offset = offset/Linelen;
n = n/Linelen;
p = a;
lock(&iomap);
for(m = iomap.m; n > 0 && m != nil; m = m->next){
if(offset-- > 0)
continue;
if(strcmp(m->tag, "dummy") == 0)
break;
sprint(buf, "%8lux %8lux %-12.12s\n", m->start, m->end-1, m->tag);
memmove(p, buf, Linelen);
p += Linelen;
n--;
}
unlock(&iomap);
return p - (char*)a;
}
static long
archwrite(Chan *c, void *a, long n, vlong offset)
{
char *p;
int port;
ushort *sp;
ulong *lp;
Rdwrfn *fn;
switch((ulong)c->qid.path){
case Qiob:
p = a;
checkport(offset, offset+n);
for(port = offset; port < offset+n; port++)
outb(port, *p++);
return n;
case Qiow:
if((n & 01) || (offset & 01))
error(Ebadarg);
checkport(offset, offset+n+1);
n /= 2;
sp = a;
for(port = offset; port < offset+n; port += 2)
outs(port, *sp++);
return n*2;
case Qiol:
if((n & 0x03) || (offset & 0x03))
error(Ebadarg);
checkport(offset, offset+n+3);
n /= 4;
lp = a;
for(port = offset; port < offset+n; port += 4)
outl(port, *lp++);
return n*4;
default:
if(c->qid.path < narchdir && (fn = writefn[c->qid.path]))
return fn(c, a, n, offset);
error(Eperm);
break;
}
return 0;
}
Dev archdevtab = {
'P',
"arch",
devreset,
devinit,
devshutdown,
archattach,
archwalk,
archstat,
archopen,
devcreate,
archclose,
archread,
devbread,
archwrite,
devbwrite,
devremove,
devwstat,
};
int
pcmspecial(char *idstr, ISAConf *isa)
{
return (_pcmspecial != nil)? _pcmspecial(idstr, isa): -1;
}
void
pcmspecialclose(int a)
{
if (_pcmspecialclose != nil)
_pcmspecialclose(a);
}