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freebsd/sys/i386/isa/loran.c
David E. O'Brien 006124d811 Use __FBSDID().
2003-06-02 16:32:55 +00:00

634 lines
16 KiB
C

/*
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@FreeBSD.org> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
*
* This device-driver helps the userland controlprogram for a LORAN-C
* receiver avoid monopolizing the CPU.
*
* This is clearly a candidate for the "most weird hardware support in
* FreeBSD" prize. At this time only two copies of the receiver are
* known to exist in the entire world.
*
* Details can be found at:
* ftp://ftp.eecis.udel.edu/pub/ntp/loran.tar.Z
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#ifdef _KERNEL
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/uio.h>
#include <sys/bus.h>
#include <sys/malloc.h>
#include <sys/timetc.h>
#include <i386/isa/isa_device.h>
#endif /* _KERNEL */
typedef TAILQ_HEAD(, datapoint) dphead_t;
struct datapoint {
/* Fields used by kernel */
u_int64_t scheduled;
u_int code;
u_int fri;
u_int agc;
u_int phase;
u_int width;
u_int par;
u_int isig;
u_int qsig;
u_int ssig;
u_int64_t epoch;
TAILQ_ENTRY(datapoint) list;
int vco;
int bounce;
pid_t pid;
struct timespec when;
int priority;
dphead_t *home;
/* Fields used only in userland */
void (*proc)(struct datapoint *);
void *ident;
int index;
char *name;
/* Fields used only in userland */
double ival;
double qval;
double sval;
double mval;
};
/*
* Mode register (PAR) hardware definitions
*/
#define INTEG 0x03 /* integrator mask */
#define INTEG_1000us 0
#define INTEG_264us 1
#define INTEG_36us 2
#define INTEG_SHORT 3
#define GATE 0x0C /* gate source mask */
#define GATE_OPEN 0x0
#define GATE_GRI 0x4
#define GATE_PCI 0x8
#define GATE_STB 0xc
#define MSB 0x10 /* load dac high-order bits */
#define IEN 0x20 /* enable interrupt bit */
#define EN5 0x40 /* enable counter 5 bit */
#define ENG 0x80 /* enable gri bit */
#define VCO_SHIFT 8 /* bits of fraction on VCO value */
#define VCO (2048 << VCO_SHIFT) /* initial vco dac (0 V)*/
#define PGUARD 990 /* program guard time (cycle) (990!) */
#ifdef _KERNEL
#define NLORAN 10 /* Allow ten minor devices */
#define NDUMMY 4 /* How many idlers we want */
#define PORT 0x0300 /* controller port address */
#define GRI 800 /* pulse-group gate (cycle) */
/*
* Analog/digital converter (ADC) hardware definitions
*/
#define ADC PORT+2 /* adc buffer (r)/address (w) */
#define ADCGO PORT+3 /* adc status (r)/adc start (w) */
#define ADC_START 0x01 /* converter start bit (w) */
#define ADC_BUSY 0x01 /* converter busy bit (r) */
#define ADC_DONE 0x80 /* converter done bit (r) */
#define ADC_I 0 /* i channel (phase) */
#define ADC_Q 1 /* q channel (amplitude) */
#define ADC_S 2 /* s channel (agc) */
/*
* Digital/analog converter (DAC) hardware definitions
* Note: output voltage increases with value programmed; the buffer
* is loaded in two 8-bit bytes, the lsb 8 bits with the MSB bit off in
* the PAR register, the msb 4 bits with the MSB on.
*/
#define DACA PORT+4 /* vco (dac a) buffer (w) */
#define DACB PORT+5 /* agc (dac b) buffer (w) */
#define LOAD_DAC(dac, val) if (0) { } else { \
par &= ~MSB; outb(PAR, par); outb((dac), (val) & 0xff); \
par |= MSB; outb(PAR, par); outb((dac), ((val) >> 8) & 0xff); \
}
/*
* Pulse-code generator (CODE) hardware definitions
* Note: bits are shifted out from the lsb first
*/
#define CODE PORT+6 /* pulse-code buffer (w) */
#define MPCA 0xCA /* LORAN-C master pulse code group a */
#define MPCB 0x9F /* LORAN-C master pulse code group b */
#define SPCA 0xF9 /* LORAN-C slave pulse code group a */
#define SPCB 0xAC /* LORAN-C slave pulse code group b */
/*
* Mode register (PAR) hardware definitions
*/
#define PAR PORT+7 /* parameter buffer (w) */
#define TGC PORT+0 /* stc control port (r/w) */
#define TGD PORT+1 /* stc data port (r/w) */
/*
* Timing generator (STC) hardware commands
*/
/* argument sssss = counter numbers 5-1 */
#define TG_LOADDP 0x00 /* load data pointer */
/* argument ee = element (all groups except ggg = 000 or 111) */
#define MODEREG 0x00 /* mode register */
#define LOADREG 0x08 /* load register */
#define HOLDREG 0x10 /* hold register */
#define HOLDINC 0x18 /* hold register (hold cycle increm) */
/* argument ee = element (group ggg = 111) */
#define ALARM1 0x07 /* alarm register 1 */
#define ALARM2 0x0F /* alarm register 2 */
#define MASTER 0x17 /* master mode register */
#define STATUS 0x1F /* status register */
#define ARM 0x20 /* arm counters */
#define LOAD 0x40 /* load counters */
#define TG_LOADARM 0x60 /* load and arm counters */
#define DISSAVE 0x80 /* disarm and save counters */
#define TG_SAVE 0xA0 /* save counters */
#define DISARM 0xC0 /* disarm counters */
/* argument nnn = counter number */
#define SETTOG 0xE8 /* set toggle output HIGH for counter */
#define CLRTOG 0xE0 /* set toggle output LOW for counter */
#define STEP 0xF0 /* step counter */
/* argument eeggg, where ee = element, ggg - counter group */
/* no arguments */
#define ENABDPS 0xE0 /* enable data pointer sequencing */
#define ENABFOUT 0xE6 /* enable fout */
#define ENAB8 0xE7 /* enable 8-bit data bus */
#define DSABDPS 0xE8 /* disable data pointer sequencing */
#define ENAB16 0xEF /* enable 16-bit data bus */
#define DSABFOUT 0xEE /* disable fout */
#define ENABPFW 0xF8 /* enable prefetch for write */
#define DSABPFW 0xF9 /* disable prefetch for write */
#define TG_RESET 0xFF /* master reset */
#define LOAD_9513(index, val) if (0) {} else { \
outb(TGC, TG_LOADDP + (index)); \
outb(TGD, (val) & 0xff); \
outb(TGD, ((val) >> 8) & 0xff); \
}
#define NENV 40 /* size of envelope filter */
#define CLOCK 50 /* clock period (clock) */
#define CYCLE 10 /* carrier period (us) */
#define PCX (NENV * CLOCK) /* envelope gate (clock) */
#define STROBE 50 /* strobe gate (clock) */
/**********************************************************************/
extern struct cdevsw loran_cdevsw;
static dphead_t minors[NLORAN + 1], working;
static struct datapoint dummy[NDUMMY], *first, *second;
static u_int64_t ticker;
static u_char par;
static MALLOC_DEFINE(M_LORAN, "Loran", "Loran datapoints");
static int loranerror;
static char lorantext[160];
static u_int vco_is;
static u_int vco_should;
static u_int vco_want;
static u_int64_t vco_when;
static int64_t vco_error;
/**********************************************************************/
static int loranprobe (struct isa_device *dvp);
static void init_tgc (void);
static int loranattach (struct isa_device *isdp);
static void loranenqueue (struct datapoint *);
static d_open_t loranopen;
static d_close_t loranclose;
static d_read_t loranread;
static d_write_t loranwrite;
static ointhand2_t loranintr;
extern struct timecounter loran_timecounter;
/**********************************************************************/
static int
loranprobe(struct isa_device *dvp)
{
dvp->id_iobase = PORT;
return (8);
}
static u_short tg_init[] = { /* stc initialization vector */
0x0562, 12, 13, /* counter 1 (p0) Mode J */
0x0262, PGUARD, GRI, /* counter 2 (gri) Mode J */
0x8562, PCX, 5000 - PCX, /* counter 3 (pcx) */
0xc562, 0, STROBE, /* counter 4 (stb) Mode L */
0x052a, 0, 0 /* counter 5 (out) */
};
static void
init_tgc(void)
{
int i;
/* Initialize the 9513A */
outb(TGC, TG_RESET); outb(TGC, LOAD+0x1f); /* reset STC chip */
LOAD_9513(MASTER, 0x8af0);
outb(TGC, TG_LOADDP+1);
tg_init[4] = 7499 - GRI;
for (i = 0; i < 5*3; i++) {
outb(TGD, tg_init[i]);
outb(TGD, tg_init[i] >> 8);
}
outb(TGC, TG_LOADARM+0x1f); /* let the good times roll */
}
static int
loranattach(struct isa_device *isdp)
{
int i;
isdp->id_ointr = loranintr;
/* We need to be a "fast-intr" */
/* isdp->id_ri_flags |= RI_FAST; XXX unimplemented - use newbus! */
printf("loran0: LORAN-C Receiver\n");
vco_want = vco_should = VCO;
vco_is = vco_should >> VCO_SHIFT;
LOAD_DAC(DACA, vco_is);
init_tgc();
tc_init(&loran_timecounter);
TAILQ_INIT(&working);
for (i = 0; i < NLORAN + 1; i++) {
TAILQ_INIT(&minors[i]);
make_dev(&loran_cdevsw, i, UID_ROOT, GID_WHEEL, 0600, "loran%d", i);
}
for (i = 0; i < NDUMMY; i++) {
dummy[i].agc = 4095;
dummy[i].code = 0xac;
dummy[i].fri = PGUARD;
dummy[i].scheduled = PGUARD * 2 * i;
dummy[i].phase = 50;
dummy[i].width = 50;
dummy[i].priority = NLORAN * 256;
dummy[i].home = &minors[NLORAN];
if (i == 0)
first = &dummy[i];
else if (i == 1)
second = &dummy[i];
else
TAILQ_INSERT_TAIL(&working, &dummy[i], list);
}
inb(ADC); /* Flush any old result */
outb(ADC, ADC_S);
par = ENG|IEN;
outb(PAR, par);
return (1);
}
static int
loranopen (dev_t dev, int flags, int fmt, struct thread *td)
{
int idx;
idx = minor(dev);
if (idx >= NLORAN)
return (ENODEV);
return(0);
}
static int
loranclose(dev_t dev, int flags, int fmt, struct thread *td)
{
return(0);
}
static int
loranread(dev_t dev, struct uio * uio, int ioflag)
{
u_long ef;
struct datapoint *this;
int err, c;
int idx;
idx = minor(dev);
if (loranerror) {
printf("Loran0: %s", lorantext);
loranerror = 0;
return(EIO);
}
if (TAILQ_EMPTY(&minors[idx]))
tsleep (&minors[idx], (PZERO + 8) |PCATCH, "loranrd", hz*2);
if (TAILQ_EMPTY(&minors[idx]))
return(0);
this = TAILQ_FIRST(&minors[idx]);
ef = read_eflags();
disable_intr();
TAILQ_REMOVE(&minors[idx], this, list);
write_eflags(ef);
c = imin(uio->uio_resid, (int)sizeof *this);
err = uiomove((caddr_t)this, c, uio);
FREE(this, M_LORAN);
return(err);
}
static void
loranenqueue(struct datapoint *dp)
{
struct datapoint *dpp;
TAILQ_FOREACH(dpp, &working, list) {
if (dpp->priority <= dp->priority)
continue;
TAILQ_INSERT_BEFORE(dpp, dp, list);
return;
}
TAILQ_INSERT_TAIL(&working, dp, list);
}
static int
loranwrite(dev_t dev, struct uio * uio, int ioflag)
{
u_long ef;
int err = 0, c;
struct datapoint *this;
int idx;
u_int64_t dt;
u_int64_t when;
idx = minor(dev);
MALLOC(this, struct datapoint *, sizeof *this, M_LORAN, M_WAITOK);
c = imin(uio->uio_resid, (int)sizeof *this);
err = uiomove((caddr_t)this, c, uio);
if (err) {
FREE(this, M_LORAN);
return (err);
}
if (this->fri == 0) {
FREE(this, M_LORAN);
return (EINVAL);
}
this->par &= INTEG|GATE;
/* XXX more checks needed! */
this->home = &minors[idx];
this->priority &= 0xff;
this->priority += idx * 256;
this->bounce = 0;
when = second->scheduled + PGUARD;
if (when > this->scheduled) {
dt = when - this->scheduled;
dt -= dt % this->fri;
this->scheduled += dt;
}
ef = read_eflags();
disable_intr();
loranenqueue(this);
write_eflags(ef);
if (this->vco >= 0)
vco_want = this->vco;
return(err);
}
static void
loranintr(int unit)
{
u_long ef;
int status = 0, i;
#if 0
int count = 0;
#endif
int delay;
u_int64_t when;
struct timespec there, then;
struct datapoint *dp, *done;
ef = read_eflags();
disable_intr();
/*
* Pick up the measurement which just completed, and setup
* the next measurement. We have 1100 microseconds for this
* of which some eaten by the A/D of the S channel and the
* interrupt to get us here.
*/
done = first;
nanotime(&there);
done->ssig = inb(ADC);
par &= ~(ENG | IEN);
outb(PAR, par);
outb(ADC, ADC_I);
outb(ADCGO, ADC_START);
/* Interlude: while we wait: setup the next measurement */
LOAD_DAC(DACB, second->agc);
outb(CODE, second->code);
par &= ~(INTEG|GATE);
par |= second->par;
par |= ENG | IEN;
while (!(inb(ADCGO) & ADC_DONE))
continue;
done->isig = inb(ADC);
outb(ADC, ADC_Q);
outb(ADCGO, ADC_START);
/* Interlude: while we wait: setup the next measurement */
/*
* We need to load this from the opposite register due to some
* weirdness which you can read about in in the 9513 manual on
* page 1-26 under "LOAD"
*/
LOAD_9513(0x0c, second->phase);
LOAD_9513(0x14, second->phase);
outb(TGC, TG_LOADARM + 0x08);
LOAD_9513(0x14, second->width);
while (!(inb(ADCGO) & ADC_DONE))
continue;
done->qsig = inb(ADC);
outb(ADC, ADC_S);
outb(PAR, par);
/*
* End of VERY time critical stuff, we have 8 msec to find
* the next measurement and program the delay.
*/
status = inb(TGC);
nanotime(&then);
first = second;
second = 0;
when = first->scheduled + PGUARD;
TAILQ_FOREACH(dp, &working, list) {
while (dp->scheduled < when)
dp->scheduled += dp->fri;
if (second && dp->scheduled + PGUARD >= second->scheduled)
continue;
second = dp;
}
delay = (second->scheduled - first->scheduled) - GRI;
LOAD_9513(0x0a, delay);
/* Done, the rest is leisure work */
vco_error += ((vco_is << VCO_SHIFT) - vco_should) *
(ticker - vco_when);
vco_should = vco_want;
i = vco_should >> VCO_SHIFT;
if (vco_error < 0)
i++;
if (vco_is != i) {
LOAD_DAC(DACA, i);
vco_is = i;
}
vco_when = ticker;
/* Check if we overran */
status &= 0x0c;
#if 0
if (status) {
outb(TGC, TG_SAVE + 2); /* save counter #2 */
outb(TGC, TG_LOADDP + 0x12); /* hold counter #2 */
count = inb(TGD);
count |= inb(TGD) << 8;
LOAD_9513(0x12, GRI)
}
#endif
if (status) {
printf( "Missed: %02x %d first:%p second:%p %.09ld\n",
status, delay, first, second,
then.tv_nsec - there.tv_nsec);
first->bounce++;
}
TAILQ_REMOVE(&working, second, list);
if (done->bounce) {
done->bounce = 0;
loranenqueue(done);
} else {
done->epoch = ticker;
done->vco = vco_is;
done->when = there;
TAILQ_INSERT_TAIL(done->home, done, list);
wakeup(done->home);
}
ticker = first->scheduled;
while ((dp = TAILQ_FIRST(&minors[NLORAN])) != NULL) {
TAILQ_REMOVE(&minors[NLORAN], dp, list);
TAILQ_INSERT_TAIL(&working, dp, list);
}
when = second->scheduled + PGUARD;
TAILQ_FOREACH(dp, &working, list) {
while (dp->scheduled < when)
dp->scheduled += dp->fri;
}
write_eflags(ef);
}
/**********************************************************************/
static unsigned
loran_get_timecount(struct timecounter *tc)
{
unsigned count;
u_long ef;
ef = read_eflags();
disable_intr();
outb(TGC, TG_SAVE + 0x10); /* save counter #5 */
outb(TGC, TG_LOADDP +0x15); /* hold counter #5 */
count = inb(TGD);
count |= inb(TGD) << 8;
write_eflags(ef);
return (count);
}
static struct timecounter loran_timecounter = {
loran_get_timecount, /* get_timecount */
0, /* no pps_poll */
0xffff, /* counter_mask */
5000000, /* frequency */
"loran" /* name */
};
/**********************************************************************/
struct isa_driver lorandriver = {
INTR_TYPE_TTY | INTR_FAST,
loranprobe,
loranattach,
"loran"
};
COMPAT_ISA_DRIVER(loran, lorandriver);
static struct cdevsw loran_cdevsw = {
.d_open = loranopen,
.d_close = loranclose,
.d_read = loranread,
.d_write = loranwrite,
.d_name = "loran",
};
#endif /* _KERNEL */