AP_HAL_ChibiOS: move LED processing to a separate thread

LED processing on a separate thread allows much longer LED lengths to be handled without
compromising dshot timing or timeouts. The thread is also run at a lower priority to
reflect its lack of flight criticality
This commit is contained in:
Andy Piper 2023-02-23 12:35:34 +00:00 committed by Randy Mackay
parent c17fffc20d
commit 175f4dfd4f
4 changed files with 125 additions and 25 deletions

View File

@ -49,6 +49,14 @@ extern AP_IOMCU iomcu;
#endif
#define RCOU_SERIAL_TIMING_DEBUG 0
#define LED_THD_WA_SIZE 256
#ifndef HAL_NO_LED_THREAD
#if defined(HAL_NO_RCOUT_THREAD)
#define HAL_NO_LED_THREAD 1
#else
#define HAL_NO_LED_THREAD 0
#endif
#endif
#define TELEM_IC_SAMPLE 16
@ -145,6 +153,52 @@ void RCOutput::init()
_initialised = true;
}
// start the led thread
bool RCOutput::start_led_thread(void)
{
#if HAL_NO_LED_THREAD
return false;
#else
WITH_SEMAPHORE(led_thread_sem);
if (led_thread_created) {
return true;
}
if (!hal.scheduler->thread_create(FUNCTOR_BIND_MEMBER(&RCOutput::led_thread, void), "led", LED_THD_WA_SIZE, AP_HAL::Scheduler::PRIORITY_LED, 0)) {
return false;
}
led_thread_created = true;
return true;
#endif
}
/*
thread for handling LED RCOutpu
*/
void RCOutput::led_thread()
{
{
WITH_SEMAPHORE(led_thread_sem);
led_thread_ctx = chThdGetSelfX();
}
// don't start outputting until fully configured
while (!hal.scheduler->is_system_initialized()) {
hal.scheduler->delay_microseconds(1000);
}
while (true) {
chEvtWaitOne(EVT_LED_SEND);
// if DMA sharing is in effect there can be quite a delay between the request to begin the cycle and
// actually sending out data - thus we need to work out how much time we have left to collect the locks
// process any pending LED output requests
led_timer_tick(LED_OUTPUT_PERIOD_US + AP_HAL::micros64());
}
}
/*
thread for handling RCOutput send
*/
@ -163,7 +217,7 @@ void RCOutput::rcout_thread()
// dshot is quite sensitive to timing, it's important to output pulses as
// regularly as possible at the correct bitrate
while (true) {
const auto mask = chEvtWaitOne(EVT_PWM_SEND | EVT_PWM_SYNTHETIC_SEND | EVT_LED_SEND);
const auto mask = chEvtWaitOne(EVT_PWM_SEND | EVT_PWM_SYNTHETIC_SEND);
const bool have_pwm_event = (mask & (EVT_PWM_SEND | EVT_PWM_SYNTHETIC_SEND)) != 0;
// start the clock
last_thread_run_us = AP_HAL::micros64();
@ -226,13 +280,18 @@ __RAMFUNC__ void RCOutput::dshot_update_tick(void* p)
#if AP_HAL_SHARED_DMA_ENABLED
// release locks on the groups that are pending in reverse order
void RCOutput::dshot_collect_dma_locks(uint64_t time_out_us)
void RCOutput::dshot_collect_dma_locks(uint64_t time_out_us, bool led_thread)
{
if (NUM_GROUPS == 0) {
return;
}
for (int8_t i = NUM_GROUPS - 1; i >= 0; i--) {
pwm_group &group = pwm_group_list[i];
if ((led_thread && !is_led_protocol(group.current_mode)) || is_led_protocol(group.current_mode)) {
continue;
}
if (group.dma_handle != nullptr && group.dma_handle->is_locked()) {
// calculate how long we have left
uint64_t now = AP_HAL::micros64();
@ -252,7 +311,7 @@ void RCOutput::dshot_collect_dma_locks(uint64_t time_out_us)
// timer wrap with ChibiOS timers. Use CH_CFG_ST_TIMEDELTA
// as minimum. Don't allow for a very long delay (over _dshot_period_us)
// to prevent bugs in handling timer wrap
const uint32_t max_delay_us = _dshot_period_us;
const uint32_t max_delay_us = led_thread ? LED_OUTPUT_PERIOD_US : _dshot_period_us;
const uint32_t min_delay_us = 10; // matches our CH_CFG_ST_TIMEDELTA
wait_us = constrain_uint32(wait_us, min_delay_us, max_delay_us);
mask = chEvtWaitOneTimeout(group.dshot_event_mask, chTimeUS2I(wait_us));
@ -686,7 +745,7 @@ void RCOutput::push_local(void)
pwmEnableChannel(group.pwm_drv, j, width);
}
#ifndef DISABLE_DSHOT
else if (is_dshot_protocol(group.current_mode) || group.current_mode == MODE_NEOPIXEL || group.current_mode == MODE_PROFILED) {
else if (is_dshot_protocol(group.current_mode) || is_led_protocol(group.current_mode)) {
// set period_us to time for pulse output, to enable very fast rates
period_us = group.dshot_pulse_time_us;
}
@ -787,7 +846,7 @@ bool RCOutput::mode_requires_dma(enum output_mode mode) const
#ifdef DISABLE_DSHOT
return false;
#else
return is_dshot_protocol(mode) || (mode == MODE_NEOPIXEL) || (mode == MODE_PROFILED);
return is_dshot_protocol(mode) || is_led_protocol(mode);
#endif //#ifdef DISABLE_DSHOT
}
@ -945,6 +1004,11 @@ void RCOutput::set_group_mode(pwm_group &group)
uint8_t bits_per_pixel = 24;
bool active_high = true;
if (!start_led_thread()) {
group.current_mode = MODE_PWM_NONE;
break;
}
if (group.current_mode == MODE_PROFILED) {
bits_per_pixel = 25;
active_high = false;
@ -1226,17 +1290,6 @@ void RCOutput::timer_tick(uint64_t time_out_us)
return;
}
// if we have enough time left send out LED data
if (serial_led_pending && (time_out_us > (AP_HAL::micros64() + (_dshot_period_us >> 1)))) {
serial_led_pending = false;
for (auto &group : pwm_group_list) {
serial_led_pending |= !serial_led_send(group);
}
// release locks on the groups that are pending in reverse order
dshot_collect_dma_locks(time_out_us);
}
if (min_pulse_trigger_us == 0) {
return;
}
@ -1250,6 +1303,27 @@ void RCOutput::timer_tick(uint64_t time_out_us)
}
}
/*
periodic timer called from led thread. This is used for LED output
*/
void RCOutput::led_timer_tick(uint64_t time_out_us)
{
if (serial_group) {
return;
}
// if we have enough time left send out LED data
if (serial_led_pending && (time_out_us > (AP_HAL::micros64() + (LED_OUTPUT_PERIOD_US >> 1)))) {
serial_led_pending = false;
for (auto &group : pwm_group_list) {
serial_led_pending |= !serial_led_send(group);
}
// release locks on the groups that are pending in reverse order
dshot_collect_dma_locks(time_out_us, true);
}
}
// send dshot for all groups that support it
void RCOutput::dshot_send_groups(uint64_t time_out_us)
{
@ -1525,11 +1599,11 @@ void RCOutput::dshot_send(pwm_group &group, uint64_t time_out_us)
/*
send a set of Serial LED packets for a channel group
return true if send was successful
called from led thread
*/
bool RCOutput::serial_led_send(pwm_group &group)
{
if (!group.serial_led_pending
|| (group.current_mode != MODE_NEOPIXEL && group.current_mode != MODE_PROFILED)) {
if (!group.serial_led_pending || !is_led_protocol(group.current_mode)) {
return true;
}
@ -1549,7 +1623,7 @@ bool RCOutput::serial_led_send(pwm_group &group)
fill_DMA_buffer_serial_led(group);
}
group.dshot_waiter = rcout_thread_ctx;
group.dshot_waiter = led_thread_ctx;
chEvtGetAndClearEvents(group.dshot_event_mask);
@ -2176,7 +2250,7 @@ bool RCOutput::set_serial_led_num_LEDs(const uint16_t chan, uint8_t num_leds, ou
}
// we cant add more or change the type after the first setup
if (grp->current_mode == MODE_NEOPIXEL || grp->current_mode == MODE_PROFILED) {
if (is_led_protocol(grp->current_mode)) {
return false;
}
@ -2349,7 +2423,7 @@ void RCOutput::set_serial_led_rgb_data(const uint16_t chan, int8_t led, uint8_t
return;
}
if ((grp->current_mode != grp->led_mode) && ((grp->led_mode == MODE_NEOPIXEL) || (grp->led_mode == MODE_PROFILED))) {
if ((grp->current_mode != grp->led_mode) && is_led_protocol(grp->led_mode)) {
// Arrays have not yet been setup, do it now
for (uint8_t j = 0; j < 4; j++) {
delete[] grp->serial_led_data[j];
@ -2377,7 +2451,7 @@ void RCOutput::set_serial_led_rgb_data(const uint16_t chan, int8_t led, uint8_t
return;
}
} else if ((grp->current_mode != MODE_NEOPIXEL) && (grp->current_mode != MODE_PROFILED)) {
} else if (!is_led_protocol(grp->current_mode)) {
return;
}
@ -2426,6 +2500,10 @@ void RCOutput::serial_led_send(const uint16_t chan)
return;
}
if (led_thread_ctx == nullptr) {
return;
}
uint8_t i;
pwm_group *grp = find_chan(chan, i);
if (!grp) {
@ -2434,12 +2512,12 @@ void RCOutput::serial_led_send(const uint16_t chan)
WITH_SEMAPHORE(grp->serial_led_mutex);
if (grp->serial_nleds == 0 || (grp->current_mode != MODE_NEOPIXEL && grp->current_mode != MODE_PROFILED)) {
if (grp->serial_nleds == 0 || !is_led_protocol(grp->current_mode)) {
return;
}
if (grp->prepared_send) {
chEvtSignal(rcout_thread_ctx, EVT_LED_SEND);
chEvtSignal(led_thread_ctx, EVT_LED_SEND);
grp->serial_led_pending = true;
serial_led_pending = true;
}

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@ -104,6 +104,11 @@ public:
*/
void timer_tick(uint64_t last_run_us);
/*
LED push
*/
void led_timer_tick(uint64_t last_run_us);
/*
setup for serial output to a set of ESCs, using the given
baudrate. Assumes 1 start bit, 1 stop bit, LSB first and 8
@ -413,6 +418,17 @@ private:
*/
thread_t *rcout_thread_ctx;
/*
timer thread for use by led events
*/
thread_t *led_thread_ctx;
/*
mutex to control LED thread creation
*/
HAL_Semaphore led_thread_sem;
bool led_thread_created;
/*
structure for IRQ handler for soft-serial input
*/
@ -582,6 +598,10 @@ private:
// update safety switch and LED
void safety_update(void);
// LED thread
void led_thread();
bool start_led_thread();
uint32_t telem_request_mask;
/*
@ -605,7 +625,7 @@ private:
static void dshot_update_tick(void* p);
static void dshot_send_next_group(void* p);
// release locks on the groups that are pending in reverse order
void dshot_collect_dma_locks(uint64_t last_run_us);
void dshot_collect_dma_locks(uint64_t last_run_us, bool led_thread = false);
static void dma_up_irq_callback(void *p, uint32_t flags);
static void dma_unlock(void *p);
void dma_cancel(pwm_group& group);

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@ -662,6 +662,7 @@ uint8_t Scheduler::calculate_thread_priority(priority_base base, int8_t priority
{ PRIORITY_CAN, APM_CAN_PRIORITY},
{ PRIORITY_TIMER, APM_TIMER_PRIORITY},
{ PRIORITY_RCOUT, APM_RCOUT_PRIORITY},
{ PRIORITY_LED, APM_LED_PRIORITY},
{ PRIORITY_RCIN, APM_RCIN_PRIORITY},
{ PRIORITY_IO, APM_IO_PRIORITY},
{ PRIORITY_UART, APM_UART_PRIORITY},

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@ -27,6 +27,7 @@
#define APM_TIMER_PRIORITY 181
#define APM_RCOUT_PRIORITY 181
#define APM_RCIN_PRIORITY 177
#define APM_LED_PRIORITY 60
#define APM_UART_PRIORITY 60
#define APM_UART_UNBUFFERED_PRIORITY 181
#define APM_STORAGE_PRIORITY 59