diff options
Diffstat (limited to 'libhw/rp2040_hwtimer.c')
| -rw-r--r-- | libhw/rp2040_hwtimer.c | 153 |
1 files changed, 0 insertions, 153 deletions
diff --git a/libhw/rp2040_hwtimer.c b/libhw/rp2040_hwtimer.c deleted file mode 100644 index ada6246..0000000 --- a/libhw/rp2040_hwtimer.c +++ /dev/null @@ -1,153 +0,0 @@ -/* libhw/rp2040_hwtimer.c - <libhw/generic/alarmclock.h> implementation for the RP2040's hardware timer - * - * Copyright (C) 2024-2025 Luke T. Shumaker <lukeshu@lukeshu.com> - * SPDX-License-Identifier: AGPL-3.0-or-later - */ - -#include <hardware/irq.h> /* pico-sdk:hardware_irq */ -#include <hardware/timer.h> /* pico-sdk:hardware_timer */ - -#include <libcr/coroutine.h> -#include <libmisc/assert.h> - -#define IMPLEMENTATION_FOR_LIBHW_GENERIC_ALARMCLOCK_H YES -#include <libhw/generic/alarmclock.h> - -#include <libhw/rp2040_hwtimer.h> - -/******************************************************************************/ - -/** Conflict with pico-sdk:pico_time:!PICO_TIME_DEFAULT_ALARM_POOL_DISABLED. */ -void add_alarm_at(void) {}; - -/* Types **********************************************************************/ - -struct rp2040_hwtimer { - enum rp2040_hwalarm_instance alarm_num; - bool initialized; - struct alarmclock_trigger *queue; -}; -LO_IMPLEMENTATION_H(alarmclock, struct rp2040_hwtimer, rp2040_hwtimer); -LO_IMPLEMENTATION_C(alarmclock, struct rp2040_hwtimer, rp2040_hwtimer, static); - -/* Globals ********************************************************************/ - -static struct rp2040_hwtimer hwtimers[] = { - { .alarm_num = 0 }, - { .alarm_num = 1 }, - { .alarm_num = 2 }, - { .alarm_num = 3 }, -}; -static_assert(sizeof(hwtimers)/sizeof(hwtimers[0]) == _RP2040_HWALARM_NUM); - -/* Main implementation ********************************************************/ - -lo_interface alarmclock rp2040_hwtimer(enum rp2040_hwalarm_instance alarm_num) { - assert(alarm_num < _RP2040_HWALARM_NUM); - return lo_box_rp2040_hwtimer_as_alarmclock(&hwtimers[alarm_num]); -} - - -static uint64_t rp2040_hwtimer_get_time_ns(struct rp2040_hwtimer *) { - return timer_time_us_64(timer_hw) * (NS_PER_S/US_PER_S); -} - -#define NS_TO_US_ROUNDUP(x) LM_CEILDIV(x, NS_PER_S/US_PER_S) - -static void rp2040_hwtimer_intrhandler(void) { - uint irq_num = __get_current_exception() - VTABLE_FIRST_IRQ; - enum rp2040_hwalarm_instance alarm_num = TIMER_ALARM_NUM_FROM_IRQ(irq_num); - assert(alarm_num < _RP2040_HWALARM_NUM); - - struct rp2040_hwtimer *alarmclock = &hwtimers[alarm_num]; - - while (alarmclock->queue && - NS_TO_US_ROUNDUP(alarmclock->queue->fire_at_ns) <= timer_time_us_64(timer_hw)) { - struct alarmclock_trigger *trigger = alarmclock->queue; - trigger->cb(trigger->cb_arg); - alarmclock->queue = trigger->next; - trigger->alarmclock = NULL; - trigger->next = NULL; - trigger->prev = NULL; - } - - hw_clear_bits(&timer_hw->intf, 1 << alarm_num); /* Clear "force"ing the interrupt. */ - hw_clear_bits(&timer_hw->intr, 1 << alarm_num); /* Clear natural firing of the alarm. */ - if (alarmclock->queue) - timer_hw->alarm[alarm_num] = (uint32_t)NS_TO_US_ROUNDUP(alarmclock->queue->fire_at_ns); -} - -static bool rp2040_hwtimer_add_trigger(struct rp2040_hwtimer *alarmclock, - struct alarmclock_trigger *trigger, - uint64_t fire_at_ns, - void (*cb)(void *), - void *cb_arg) { - assert(alarmclock); - assert(trigger); - assert(fire_at_ns); - assert(cb); - - uint64_t now_us = timer_time_us_64(timer_hw); - if (NS_TO_US_ROUNDUP(fire_at_ns) > now_us && - (NS_TO_US_ROUNDUP(fire_at_ns) - now_us) > UINT32_MAX) - /* Too far in the future. */ - return true; - - trigger->alarmclock = alarmclock; - trigger->fire_at_ns = fire_at_ns; - trigger->cb = cb; - trigger->cb_arg = cb_arg; - - bool saved = cr_save_and_disable_interrupts(); - struct alarmclock_trigger **dst = &alarmclock->queue; - while (*dst && fire_at_ns >= (*dst)->fire_at_ns) - dst = &(*dst)->next; - trigger->next = *dst; - trigger->prev = *dst ? (*dst)->prev : NULL; - if (*dst) - (*dst)->prev = trigger; - *dst = trigger; - if (!alarmclock->initialized) { - hw_set_bits(&timer_hw->inte, 1 << alarmclock->alarm_num); - irq_set_exclusive_handler(TIMER_ALARM_IRQ_NUM(timer_hw, alarmclock->alarm_num), - rp2040_hwtimer_intrhandler); - irq_set_enabled(TIMER_ALARM_IRQ_NUM(timer_hw, alarmclock->alarm_num), true); - alarmclock->initialized = true; - } - if (alarmclock->queue == trigger) { - /* "Force" the interrupt handler to trigger as soon as - * we enable interrupts. This handles the case of - * when fire_at_ns is before when we called - * cr_save_and_disable_interrupts(). We could check - * timer_time_us_64() again after calling - * cr_save_and_disable_interrupts() and do this - * conditionally, but I don't think that would be any - * more efficient than just letting the interrupt - * fire. */ - hw_set_bits(&timer_hw->intf, 1 << alarmclock->alarm_num); - } - cr_restore_interrupts(saved); - - return false; -} - -static void rp2040_hwtimer_del_trigger(struct rp2040_hwtimer *alarmclock, - struct alarmclock_trigger *trigger) { - assert(alarmclock); - assert(trigger); - - bool saved = cr_save_and_disable_interrupts(); - if (trigger->alarmclock == alarmclock) { - if (!trigger->prev) - alarmclock->queue = trigger->next; - else - trigger->prev->next = trigger->next; - if (trigger->next) - trigger->next->prev = trigger->prev; - trigger->alarmclock = NULL; - trigger->prev = NULL; - trigger->next = NULL; - } else - assert(!trigger->alarmclock); - cr_restore_interrupts(saved); -} |