Sergey Solodunov / mbed-dev

mbed library sources. Supersedes mbed-src.

Fork of mbed-dev by mbed official

targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/us_ticker.c@15:a81a8d6c1dfe, 2015-11-04 (annotated)

Committer:
mbed_official
Date:
Wed Nov 04 16:30:11 2015 +0000
Revision:
15:a81a8d6c1dfe
Child:
18:da299f395b9e
Synchronized with git revision 46af745ef4405614c3fa49abbd9a706a362ea514



Full URL: https://github.com/mbedmicro/mbed/commit/46af745ef4405614c3fa49abbd9a706a362ea514/



Renamed TARGET_SAM_CortexM0+ to TARGET_SAM_CortexM0P for compatiblity with online compiler

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 15:a81a8d6c1dfe 1 /* mbed Microcontroller Library
mbed_official 15:a81a8d6c1dfe 2 * Copyright (c) 2006-2015 ARM Limited
mbed_official 15:a81a8d6c1dfe 3 *
mbed_official 15:a81a8d6c1dfe 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 15:a81a8d6c1dfe 5 * you may not use this file except in compliance with the License.
mbed_official 15:a81a8d6c1dfe 6 * You may obtain a copy of the License at
mbed_official 15:a81a8d6c1dfe 7 *
mbed_official 15:a81a8d6c1dfe 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 15:a81a8d6c1dfe 9 *
mbed_official 15:a81a8d6c1dfe 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 15:a81a8d6c1dfe 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 15:a81a8d6c1dfe 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 15:a81a8d6c1dfe 13 * See the License for the specific language governing permissions and
mbed_official 15:a81a8d6c1dfe 14 * limitations under the License.
mbed_official 15:a81a8d6c1dfe 15 */
mbed_official 15:a81a8d6c1dfe 16 #include <stddef.h>
mbed_official 15:a81a8d6c1dfe 17 #include "us_ticker_api.h"
mbed_official 15:a81a8d6c1dfe 18 #include "cmsis.h"
mbed_official 15:a81a8d6c1dfe 19 #include "mbed_assert.h"
mbed_official 15:a81a8d6c1dfe 20 #include "ins_gclk.h"
mbed_official 15:a81a8d6c1dfe 21 #include "compiler.h"
mbed_official 15:a81a8d6c1dfe 22 #include "system.h"
mbed_official 15:a81a8d6c1dfe 23 #include "tc.h"
mbed_official 15:a81a8d6c1dfe 24 #include "tc_interrupt.h"
mbed_official 15:a81a8d6c1dfe 25
mbed_official 15:a81a8d6c1dfe 26 #define TICKER_COUNTER_uS TC4
mbed_official 15:a81a8d6c1dfe 27 #define TICKER_COUNTER_IRQn TC4_IRQn
mbed_official 15:a81a8d6c1dfe 28 #define TICKER_COUNTER_Handlr TC4_Handler
mbed_official 15:a81a8d6c1dfe 29
mbed_official 15:a81a8d6c1dfe 30 static int us_ticker_inited = 0;
mbed_official 15:a81a8d6c1dfe 31 extern uint8_t g_sys_init;
mbed_official 15:a81a8d6c1dfe 32
mbed_official 15:a81a8d6c1dfe 33 struct tc_module us_ticker_module;
mbed_official 15:a81a8d6c1dfe 34
mbed_official 15:a81a8d6c1dfe 35
mbed_official 15:a81a8d6c1dfe 36 static inline void tc_clear_interrupt(
mbed_official 15:a81a8d6c1dfe 37 struct tc_module *const module,
mbed_official 15:a81a8d6c1dfe 38 const enum tc_callback callback_type)
mbed_official 15:a81a8d6c1dfe 39 {
mbed_official 15:a81a8d6c1dfe 40 /* Sanity check arguments */
mbed_official 15:a81a8d6c1dfe 41 MBED_ASSERT(module);
mbed_official 15:a81a8d6c1dfe 42
mbed_official 15:a81a8d6c1dfe 43 /* Clear interrupt flags */
mbed_official 15:a81a8d6c1dfe 44 if (callback_type == TC_CALLBACK_CC_CHANNEL0) {
mbed_official 15:a81a8d6c1dfe 45 module->hw->COUNT8.INTENCLR.reg = TC_INTFLAG_MC(1);
mbed_official 15:a81a8d6c1dfe 46 } else if (callback_type == TC_CALLBACK_CC_CHANNEL1) {
mbed_official 15:a81a8d6c1dfe 47 module->hw->COUNT8.INTENCLR.reg = TC_INTFLAG_MC(2);
mbed_official 15:a81a8d6c1dfe 48 } else {
mbed_official 15:a81a8d6c1dfe 49 module->hw->COUNT8.INTENCLR.reg = (1 << callback_type);
mbed_official 15:a81a8d6c1dfe 50 }
mbed_official 15:a81a8d6c1dfe 51 }
mbed_official 15:a81a8d6c1dfe 52
mbed_official 15:a81a8d6c1dfe 53 void us_ticker_irq_handler_internal(struct tc_module* us_tc_module)
mbed_official 15:a81a8d6c1dfe 54 {
mbed_official 15:a81a8d6c1dfe 55 uint32_t status_flags;
mbed_official 15:a81a8d6c1dfe 56
mbed_official 15:a81a8d6c1dfe 57 /* Clear TC capture overflow and TC count overflow */
mbed_official 15:a81a8d6c1dfe 58 status_flags = TC_STATUS_CAPTURE_OVERFLOW | TC_STATUS_COUNT_OVERFLOW;
mbed_official 15:a81a8d6c1dfe 59 tc_clear_status(&us_ticker_module, status_flags);
mbed_official 15:a81a8d6c1dfe 60
mbed_official 15:a81a8d6c1dfe 61 us_ticker_irq_handler();
mbed_official 15:a81a8d6c1dfe 62 }
mbed_official 15:a81a8d6c1dfe 63
mbed_official 15:a81a8d6c1dfe 64 void us_ticker_init(void)
mbed_official 15:a81a8d6c1dfe 65 {
mbed_official 15:a81a8d6c1dfe 66 uint32_t cycles_per_us;
mbed_official 15:a81a8d6c1dfe 67 uint32_t prescaler = 0;
mbed_official 15:a81a8d6c1dfe 68 struct tc_config config_tc;
mbed_official 15:a81a8d6c1dfe 69 enum status_code ret_status;
mbed_official 15:a81a8d6c1dfe 70
mbed_official 15:a81a8d6c1dfe 71 if (us_ticker_inited) return;
mbed_official 15:a81a8d6c1dfe 72 us_ticker_inited = 1;
mbed_official 15:a81a8d6c1dfe 73
mbed_official 15:a81a8d6c1dfe 74 if (g_sys_init == 0) {
mbed_official 15:a81a8d6c1dfe 75 system_init();
mbed_official 15:a81a8d6c1dfe 76 g_sys_init = 1;
mbed_official 15:a81a8d6c1dfe 77 }
mbed_official 15:a81a8d6c1dfe 78
mbed_official 15:a81a8d6c1dfe 79 tc_get_config_defaults(&config_tc);
mbed_official 15:a81a8d6c1dfe 80
mbed_official 15:a81a8d6c1dfe 81 cycles_per_us = system_gclk_gen_get_hz(config_tc.clock_source) / 1000000;
mbed_official 15:a81a8d6c1dfe 82 MBED_ASSERT(cycles_per_us > 0);
mbed_official 15:a81a8d6c1dfe 83 /*while((cycles_per_us & 1) == 0 && prescaler <= 10) {
mbed_official 15:a81a8d6c1dfe 84 cycles_per_us = cycles_per_us >> 1;
mbed_official 15:a81a8d6c1dfe 85 prescaler++;
mbed_official 15:a81a8d6c1dfe 86 }*/
mbed_official 15:a81a8d6c1dfe 87 while((cycles_per_us > 1) && (prescaler <= 10)) {
mbed_official 15:a81a8d6c1dfe 88 cycles_per_us = cycles_per_us >> 1;
mbed_official 15:a81a8d6c1dfe 89 prescaler++;
mbed_official 15:a81a8d6c1dfe 90 }
mbed_official 15:a81a8d6c1dfe 91 if (prescaler >= 9) {
mbed_official 15:a81a8d6c1dfe 92 prescaler = 7;
mbed_official 15:a81a8d6c1dfe 93 } else if (prescaler >= 7) {
mbed_official 15:a81a8d6c1dfe 94 prescaler = 6;
mbed_official 15:a81a8d6c1dfe 95 } else if (prescaler >= 5) {
mbed_official 15:a81a8d6c1dfe 96 prescaler = 5;
mbed_official 15:a81a8d6c1dfe 97 }
mbed_official 15:a81a8d6c1dfe 98
mbed_official 15:a81a8d6c1dfe 99 config_tc.clock_prescaler = TC_CTRLA_PRESCALER(prescaler);
mbed_official 15:a81a8d6c1dfe 100 config_tc.counter_size = TC_COUNTER_SIZE_32BIT;
mbed_official 15:a81a8d6c1dfe 101 config_tc.run_in_standby = true;
mbed_official 15:a81a8d6c1dfe 102 config_tc.counter_32_bit.value = 0;
mbed_official 15:a81a8d6c1dfe 103 config_tc.counter_32_bit.compare_capture_channel[TC_COMPARE_CAPTURE_CHANNEL_0] = 0xFFFFFFFF;
mbed_official 15:a81a8d6c1dfe 104
mbed_official 15:a81a8d6c1dfe 105 /* Initialize the timer */
mbed_official 15:a81a8d6c1dfe 106 ret_status = tc_init(&us_ticker_module, TICKER_COUNTER_uS, &config_tc);
mbed_official 15:a81a8d6c1dfe 107 MBED_ASSERT(ret_status == STATUS_OK);
mbed_official 15:a81a8d6c1dfe 108
mbed_official 15:a81a8d6c1dfe 109 /* Register callback function */
mbed_official 15:a81a8d6c1dfe 110 tc_register_callback(&us_ticker_module, (tc_callback_t)us_ticker_irq_handler_internal, TC_CALLBACK_CC_CHANNEL0);
mbed_official 15:a81a8d6c1dfe 111
mbed_official 15:a81a8d6c1dfe 112 /* Enable the timer module */
mbed_official 15:a81a8d6c1dfe 113 tc_enable(&us_ticker_module);
mbed_official 15:a81a8d6c1dfe 114 }
mbed_official 15:a81a8d6c1dfe 115
mbed_official 15:a81a8d6c1dfe 116 uint32_t us_ticker_read()
mbed_official 15:a81a8d6c1dfe 117 {
mbed_official 15:a81a8d6c1dfe 118 if (!us_ticker_inited)
mbed_official 15:a81a8d6c1dfe 119 us_ticker_init();
mbed_official 15:a81a8d6c1dfe 120
mbed_official 15:a81a8d6c1dfe 121 return tc_get_count_value(&us_ticker_module);
mbed_official 15:a81a8d6c1dfe 122 }
mbed_official 15:a81a8d6c1dfe 123
mbed_official 15:a81a8d6c1dfe 124 void us_ticker_set_interrupt(timestamp_t timestamp)
mbed_official 15:a81a8d6c1dfe 125 {
mbed_official 15:a81a8d6c1dfe 126 uint32_t cur_time;
mbed_official 15:a81a8d6c1dfe 127 int32_t delta;
mbed_official 15:a81a8d6c1dfe 128
mbed_official 15:a81a8d6c1dfe 129 cur_time = us_ticker_read();
mbed_official 15:a81a8d6c1dfe 130 delta = (int32_t)((uint32_t)timestamp - cur_time);
mbed_official 15:a81a8d6c1dfe 131 if (delta < 0) {
mbed_official 15:a81a8d6c1dfe 132 /* Event already occurred in past */
mbed_official 15:a81a8d6c1dfe 133 us_ticker_irq_handler();
mbed_official 15:a81a8d6c1dfe 134 return;
mbed_official 15:a81a8d6c1dfe 135 }
mbed_official 15:a81a8d6c1dfe 136
mbed_official 15:a81a8d6c1dfe 137 NVIC_DisableIRQ(TICKER_COUNTER_IRQn);
mbed_official 15:a81a8d6c1dfe 138 NVIC_SetVector(TICKER_COUNTER_IRQn, (uint32_t)TICKER_COUNTER_Handlr);
mbed_official 15:a81a8d6c1dfe 139
mbed_official 15:a81a8d6c1dfe 140 /* Enable the callback */
mbed_official 15:a81a8d6c1dfe 141 tc_enable_callback(&us_ticker_module, TC_CALLBACK_CC_CHANNEL0);
mbed_official 15:a81a8d6c1dfe 142 tc_set_compare_value(&us_ticker_module, TC_COMPARE_CAPTURE_CHANNEL_0, (uint32_t)timestamp);
mbed_official 15:a81a8d6c1dfe 143
mbed_official 15:a81a8d6c1dfe 144 NVIC_EnableIRQ(TICKER_COUNTER_IRQn);
mbed_official 15:a81a8d6c1dfe 145 }
mbed_official 15:a81a8d6c1dfe 146
mbed_official 15:a81a8d6c1dfe 147 void us_ticker_disable_interrupt(void)
mbed_official 15:a81a8d6c1dfe 148 {
mbed_official 15:a81a8d6c1dfe 149 /* Disable the callback */
mbed_official 15:a81a8d6c1dfe 150 tc_disable_callback(&us_ticker_module, TC_CALLBACK_CC_CHANNEL0);
mbed_official 15:a81a8d6c1dfe 151 NVIC_DisableIRQ(TICKER_COUNTER_IRQn);
mbed_official 15:a81a8d6c1dfe 152 }
mbed_official 15:a81a8d6c1dfe 153
mbed_official 15:a81a8d6c1dfe 154 void us_ticker_clear_interrupt(void)
mbed_official 15:a81a8d6c1dfe 155 {
mbed_official 15:a81a8d6c1dfe 156 uint32_t status_flags;
mbed_official 15:a81a8d6c1dfe 157
mbed_official 15:a81a8d6c1dfe 158 /* Clear TC channel 0 match */
mbed_official 15:a81a8d6c1dfe 159 status_flags = TC_STATUS_CHANNEL_0_MATCH;
mbed_official 15:a81a8d6c1dfe 160 tc_clear_status(&us_ticker_module, status_flags);
mbed_official 15:a81a8d6c1dfe 161
mbed_official 15:a81a8d6c1dfe 162 /* Clear the interrupt */
mbed_official 15:a81a8d6c1dfe 163 tc_clear_interrupt(&us_ticker_module, TC_CALLBACK_CC_CHANNEL0);
mbed_official 15:a81a8d6c1dfe 164 NVIC_ClearPendingIRQ(TICKER_COUNTER_IRQn);
mbed_official 15:a81a8d6c1dfe 165 }