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Improve mp_hal_delay_ms by implementing subtick resolution.

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This commit is contained in:
eightycc 2025-05-06 11:01:05 -07:00
parent 7b12bc8837
commit fcf7df857e
2 changed files with 27 additions and 10 deletions
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30
supervisor/shared/tick.c
View file

@ -85,6 +85,13 @@ void supervisor_tick(void) {
background_callback_add(&tick_callback, supervisor_background_tick, NULL);
}
uint64_t supervisor_get_raw_subticks(void) {
uint64_t ticks;
uint8_t subticks;
ticks = port_get_raw_ticks(&subticks);
return (ticks << 5) | subticks;
}
uint64_t supervisor_ticks_ms64() {
uint64_t result;
result = port_get_raw_ticks(NULL);
@ -97,26 +104,29 @@ uint32_t supervisor_ticks_ms32() {
}
void mp_hal_delay_ms(mp_uint_t delay_ms) {
uint64_t start_tick = port_get_raw_ticks(NULL);
// Adjust the delay to ticks vs ms.
uint64_t delay_ticks = (delay_ms * (uint64_t)1024) / 1000;
uint64_t end_tick = start_tick + delay_ticks;
int64_t remaining = delay_ticks;
uint64_t start_subtick = supervisor_get_raw_subticks();
// Convert delay from ms to subticks
uint64_t delay_subticks = (delay_ms * (uint64_t)32768) / 1000;
uint64_t end_subtick = start_subtick + delay_subticks;
int64_t remaining = delay_subticks;
// Loop until we've waited long enough or we've been CTRL-Ced by autoreload
// or the user.
while (remaining > 0 && !mp_hal_is_interrupted()) {
RUN_BACKGROUND_TASKS;
remaining = end_tick - port_get_raw_ticks(NULL);
remaining = end_subtick - supervisor_get_raw_subticks();
// We break a bit early so we don't risk setting the alarm before the time when we call
// sleep.
if (remaining < 1) {
break;
}
port_interrupt_after_ticks(remaining);
// Idle until an interrupt happens.
port_idle_until_interrupt();
remaining = end_tick - port_get_raw_ticks(NULL);
uint32_t remaining_ticks = remaining / 32;
if (remaining_ticks > 0) {
port_interrupt_after_ticks(remaining_ticks);
// Idle until an interrupt happens.
port_idle_until_interrupt();
}
remaining = end_subtick - supervisor_get_raw_subticks();
}
}

7
supervisor/shared/tick.h
View file

@ -33,6 +33,13 @@ extern uint32_t supervisor_ticks_ms32(void);
*/
extern uint64_t supervisor_ticks_ms64(void);
/** @brief Get 64-bit current time in subticks
*
* Time is returned as a 64-bit count of subticks where each subtick is 1/32768
* of a second.
*/
extern uint64_t supervisor_get_raw_subticks(void);
extern void supervisor_enable_tick(void);
extern void supervisor_disable_tick(void);