circuitpython/cc3200/misc/mpsystick.c

72 lines
2.6 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
* Copyright (c) 2015 Daniel Campora
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "py/mpconfig.h"
#include "py/obj.h"
#include "py/mphal.h"
#include "mpsystick.h"
#include "systick.h"
#include "inc/hw_types.h"
#include "inc/hw_nvic.h"
#ifdef USE_FREERTOS
#include "FreeRTOS.h"
#include "task.h"
#endif
bool sys_tick_has_passed(uint32_t start_tick, uint32_t delay_ms) {
return mp_hal_ticks_ms() - start_tick >= delay_ms;
}
// waits until at least delay_ms milliseconds have passed from the sampling of
// startTick. Handles overflow properly. Assumes stc was taken from
// mp_hal_ticks_ms() some time before calling this function.
void sys_tick_wait_at_least(uint32_t start_tick, uint32_t delay_ms) {
#ifdef USE_FREERTOS
vTaskDelay (delay_ms / portTICK_PERIOD_MS);
#else
while (!sys_tick_has_passed(start_tick, delay_ms)) {
__WFI(); // enter sleep mode, waiting for interrupt
}
#endif
}
// The SysTick timer counts down at HAL_FCPU_HZ, so we can use that knowledge
// to grab a microsecond counter.
// We assume that mp_hal_ticks_ms returns milliseconds.
uint32_t sys_tick_get_microseconds(void) {
mp_uint_t irq_state = disable_irq();
uint32_t counter = SysTickValueGet();
uint32_t milliseconds = mp_hal_ticks_ms();
enable_irq(irq_state);
uint32_t load = SysTickPeriodGet();
counter = load - counter; // Convert from decrementing to incrementing
return (milliseconds * 1000) + ((counter * 1000) / load);
}