klipper/src/stepper.c

352 lines
11 KiB
C

// Handling of stepper drivers.
//
// Copyright (C) 2016-2021 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include "autoconf.h" // CONFIG_*
#include "basecmd.h" // oid_alloc
#include "board/gpio.h" // gpio_out_write
#include "board/irq.h" // irq_disable
#include "board/misc.h" // timer_is_before
#include "command.h" // DECL_COMMAND
#include "sched.h" // struct timer
#include "stepper.h" // stepper_event
#include "trsync.h" // trsync_add_signal
#if CONFIG_INLINE_STEPPER_HACK && CONFIG_HAVE_STEPPER_BOTH_EDGE
#define HAVE_SINGLE_SCHEDULE 1
#define HAVE_EDGE_OPTIMIZATION 1
#define HAVE_AVR_OPTIMIZATION 0
DECL_CONSTANT("STEPPER_BOTH_EDGE", 1);
#elif CONFIG_INLINE_STEPPER_HACK && CONFIG_MACH_AVR
#define HAVE_SINGLE_SCHEDULE 1
#define HAVE_EDGE_OPTIMIZATION 0
#define HAVE_AVR_OPTIMIZATION 1
#else
#define HAVE_SINGLE_SCHEDULE 0
#define HAVE_EDGE_OPTIMIZATION 0
#define HAVE_AVR_OPTIMIZATION 0
#endif
struct stepper_move {
struct move_node node;
uint32_t interval;
int16_t add;
uint16_t count;
uint8_t flags;
};
enum { MF_DIR=1<<0 };
struct stepper {
struct timer time;
uint32_t interval;
int16_t add;
uint32_t count;
uint32_t next_step_time, step_pulse_ticks;
struct gpio_out step_pin, dir_pin;
uint32_t position;
struct move_queue_head mq;
struct trsync_signal stop_signal;
// gcc (pre v6) does better optimization when uint8_t are bitfields
uint8_t flags : 8;
};
enum { POSITION_BIAS=0x40000000 };
enum {
SF_LAST_DIR=1<<0, SF_NEXT_DIR=1<<1, SF_INVERT_STEP=1<<2, SF_NEED_RESET=1<<3,
SF_SINGLE_SCHED=1<<4, SF_HAVE_ADD=1<<5
};
// Setup a stepper for the next move in its queue
static uint_fast8_t
stepper_load_next(struct stepper *s)
{
if (move_queue_empty(&s->mq)) {
// There is no next move - the queue is empty
s->count = 0;
return SF_DONE;
}
// Load next 'struct stepper_move' into 'struct stepper'
struct move_node *mn = move_queue_pop(&s->mq);
struct stepper_move *m = container_of(mn, struct stepper_move, node);
s->add = m->add;
s->interval = m->interval + m->add;
if (HAVE_SINGLE_SCHEDULE && s->flags & SF_SINGLE_SCHED) {
s->time.waketime += m->interval;
if (HAVE_AVR_OPTIMIZATION)
s->flags = m->add ? s->flags|SF_HAVE_ADD : s->flags & ~SF_HAVE_ADD;
s->count = m->count;
} else {
// It is necessary to schedule unstep events and so there are
// twice as many events.
s->next_step_time += m->interval;
s->time.waketime = s->next_step_time;
s->count = (uint32_t)m->count * 2;
}
// Add all steps to s->position (stepper_get_position() can calc mid-move)
if (m->flags & MF_DIR) {
s->position = -s->position + m->count;
gpio_out_toggle_noirq(s->dir_pin);
} else {
s->position += m->count;
}
move_free(m);
return SF_RESCHEDULE;
}
// Optimized step function to step on each step pin edge
uint_fast8_t
stepper_event_edge(struct timer *t)
{
struct stepper *s = container_of(t, struct stepper, time);
gpio_out_toggle_noirq(s->step_pin);
uint32_t count = s->count - 1;
if (likely(count)) {
s->count = count;
s->time.waketime += s->interval;
s->interval += s->add;
return SF_RESCHEDULE;
}
return stepper_load_next(s);
}
#define AVR_STEP_INSNS 40 // minimum instructions between step gpio pulses
// AVR optimized step function
static uint_fast8_t
stepper_event_avr(struct timer *t)
{
struct stepper *s = container_of(t, struct stepper, time);
gpio_out_toggle_noirq(s->step_pin);
uint16_t *pcount = (void*)&s->count, count = *pcount - 1;
if (likely(count)) {
*pcount = count;
s->time.waketime += s->interval;
gpio_out_toggle_noirq(s->step_pin);
if (s->flags & SF_HAVE_ADD)
s->interval += s->add;
return SF_RESCHEDULE;
}
uint_fast8_t ret = stepper_load_next(s);
gpio_out_toggle_noirq(s->step_pin);
return ret;
}
// Regular "double scheduled" step function
uint_fast8_t
stepper_event_full(struct timer *t)
{
struct stepper *s = container_of(t, struct stepper, time);
gpio_out_toggle_noirq(s->step_pin);
uint32_t curtime = timer_read_time();
uint32_t min_next_time = curtime + s->step_pulse_ticks;
s->count--;
if (likely(s->count & 1))
// Schedule unstep event
goto reschedule_min;
if (likely(s->count)) {
s->next_step_time += s->interval;
s->interval += s->add;
if (unlikely(timer_is_before(s->next_step_time, min_next_time)))
// The next step event is too close - push it back
goto reschedule_min;
s->time.waketime = s->next_step_time;
return SF_RESCHEDULE;
}
uint_fast8_t ret = stepper_load_next(s);
if (ret == SF_DONE || !timer_is_before(s->time.waketime, min_next_time))
return ret;
// Next step event is too close to the last unstep
int32_t diff = s->time.waketime - min_next_time;
if (diff < (int32_t)-timer_from_us(1000))
shutdown("Stepper too far in past");
reschedule_min:
s->time.waketime = min_next_time;
return SF_RESCHEDULE;
}
// Optimized entry point for step function (may be inlined into sched.c code)
uint_fast8_t
stepper_event(struct timer *t)
{
if (HAVE_EDGE_OPTIMIZATION)
return stepper_event_edge(t);
if (HAVE_AVR_OPTIMIZATION)
return stepper_event_avr(t);
return stepper_event_full(t);
}
void
command_config_stepper(uint32_t *args)
{
struct stepper *s = oid_alloc(args[0], command_config_stepper, sizeof(*s));
int_fast8_t invert_step = args[3];
s->flags = invert_step > 0 ? SF_INVERT_STEP : 0;
s->step_pin = gpio_out_setup(args[1], s->flags & SF_INVERT_STEP);
s->dir_pin = gpio_out_setup(args[2], 0);
s->position = -POSITION_BIAS;
s->step_pulse_ticks = args[4];
move_queue_setup(&s->mq, sizeof(struct stepper_move));
if (HAVE_EDGE_OPTIMIZATION) {
if (!s->step_pulse_ticks && invert_step < 0)
s->flags |= SF_SINGLE_SCHED;
else
s->time.func = stepper_event_full;
} else if (HAVE_AVR_OPTIMIZATION) {
if (s->step_pulse_ticks <= AVR_STEP_INSNS)
s->flags |= SF_SINGLE_SCHED;
else
s->time.func = stepper_event_full;
} else if (!CONFIG_INLINE_STEPPER_HACK) {
s->time.func = stepper_event_full;
}
}
DECL_COMMAND(command_config_stepper, "config_stepper oid=%c step_pin=%c"
" dir_pin=%c invert_step=%c step_pulse_ticks=%u");
// Return the 'struct stepper' for a given stepper oid
static struct stepper *
stepper_oid_lookup(uint8_t oid)
{
return oid_lookup(oid, command_config_stepper);
}
// Schedule a set of steps with a given timing
void
command_queue_step(uint32_t *args)
{
struct stepper *s = stepper_oid_lookup(args[0]);
struct stepper_move *m = move_alloc();
m->interval = args[1];
m->count = args[2];
if (!m->count)
shutdown("Invalid count parameter");
m->add = args[3];
m->flags = 0;
irq_disable();
uint8_t flags = s->flags;
if (!!(flags & SF_LAST_DIR) != !!(flags & SF_NEXT_DIR)) {
flags ^= SF_LAST_DIR;
m->flags |= MF_DIR;
}
if (s->count) {
s->flags = flags;
move_queue_push(&m->node, &s->mq);
} else if (flags & SF_NEED_RESET) {
move_free(m);
} else {
s->flags = flags;
move_queue_push(&m->node, &s->mq);
stepper_load_next(s);
sched_add_timer(&s->time);
}
irq_enable();
}
DECL_COMMAND(command_queue_step,
"queue_step oid=%c interval=%u count=%hu add=%hi");
// Set the direction of the next queued step
void
command_set_next_step_dir(uint32_t *args)
{
struct stepper *s = stepper_oid_lookup(args[0]);
uint8_t nextdir = args[1] ? SF_NEXT_DIR : 0;
irq_disable();
s->flags = (s->flags & ~SF_NEXT_DIR) | nextdir;
irq_enable();
}
DECL_COMMAND(command_set_next_step_dir, "set_next_step_dir oid=%c dir=%c");
// Set an absolute time that the next step will be relative to
void
command_reset_step_clock(uint32_t *args)
{
struct stepper *s = stepper_oid_lookup(args[0]);
uint32_t waketime = args[1];
irq_disable();
if (s->count)
shutdown("Can't reset time when stepper active");
s->next_step_time = s->time.waketime = waketime;
s->flags &= ~SF_NEED_RESET;
irq_enable();
}
DECL_COMMAND(command_reset_step_clock, "reset_step_clock oid=%c clock=%u");
// Return the current stepper position. Caller must disable irqs.
static uint32_t
stepper_get_position(struct stepper *s)
{
uint32_t position = s->position;
// If stepper is mid-move, subtract out steps not yet taken
if (HAVE_SINGLE_SCHEDULE && s->flags & SF_SINGLE_SCHED)
position -= s->count;
else
position -= s->count / 2;
// The top bit of s->position is an optimized reverse direction flag
if (position & 0x80000000)
return -position;
return position;
}
// Report the current position of the stepper
void
command_stepper_get_position(uint32_t *args)
{
uint8_t oid = args[0];
struct stepper *s = stepper_oid_lookup(oid);
irq_disable();
uint32_t position = stepper_get_position(s);
irq_enable();
sendf("stepper_position oid=%c pos=%i", oid, position - POSITION_BIAS);
}
DECL_COMMAND(command_stepper_get_position, "stepper_get_position oid=%c");
// Stop all moves for a given stepper (caller must disable IRQs)
static void
stepper_stop(struct trsync_signal *tss, uint8_t reason)
{
struct stepper *s = container_of(tss, struct stepper, stop_signal);
sched_del_timer(&s->time);
s->next_step_time = s->time.waketime = 0;
s->position = -stepper_get_position(s);
s->count = 0;
s->flags = (s->flags & (SF_INVERT_STEP|SF_SINGLE_SCHED)) | SF_NEED_RESET;
gpio_out_write(s->dir_pin, 0);
if (!(HAVE_EDGE_OPTIMIZATION && s->flags & SF_SINGLE_SCHED))
gpio_out_write(s->step_pin, s->flags & SF_INVERT_STEP);
while (!move_queue_empty(&s->mq)) {
struct move_node *mn = move_queue_pop(&s->mq);
struct stepper_move *m = container_of(mn, struct stepper_move, node);
move_free(m);
}
}
// Set the stepper to stop on a "trigger event" (used in homing)
void
command_stepper_stop_on_trigger(uint32_t *args)
{
struct stepper *s = stepper_oid_lookup(args[0]);
struct trsync *ts = trsync_oid_lookup(args[1]);
trsync_add_signal(ts, &s->stop_signal, stepper_stop);
}
DECL_COMMAND(command_stepper_stop_on_trigger,
"stepper_stop_on_trigger oid=%c trsync_oid=%c");
void
stepper_shutdown(void)
{
uint8_t i;
struct stepper *s;
foreach_oid(i, s, command_config_stepper) {
move_queue_clear(&s->mq);
stepper_stop(&s->stop_signal, 0);
}
}
DECL_SHUTDOWN(stepper_shutdown);