mbed official / mbed-dev

mbed library sources. Supersedes mbed-src.

Dependents:   Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more

targets/TARGET_ARM_FM/TARGET_FVP_MPS2/us_ticker.c@189:f392fc9709a3, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 22:31:08 2019 +0000
Revision:
189:f392fc9709a3
Parent:
187:0387e8f68319 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Anna Bridge 186:707f6e361f3e 1 /* mbed Microcontroller Library
Anna Bridge 186:707f6e361f3e 2 * Copyright (c) 2006-2018 ARM Limited
Anna Bridge 186:707f6e361f3e 3 *
Anna Bridge 186:707f6e361f3e 4 * Licensed under the Apache License, Version 2.0 (the "License");
Anna Bridge 186:707f6e361f3e 5 * you may not use this file except in compliance with the License.
Anna Bridge 186:707f6e361f3e 6 * You may obtain a copy of the License at
Anna Bridge 186:707f6e361f3e 7 *
Anna Bridge 186:707f6e361f3e 8 * http://www.apache.org/licenses/LICENSE-2.0
Anna Bridge 186:707f6e361f3e 9 *
Anna Bridge 186:707f6e361f3e 10 * Unless required by applicable law or agreed to in writing, software
Anna Bridge 186:707f6e361f3e 11 * distributed under the License is distributed on an "AS IS" BASIS,
Anna Bridge 186:707f6e361f3e 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
Anna Bridge 186:707f6e361f3e 13 * See the License for the specific language governing permissions and
Anna Bridge 186:707f6e361f3e 14 * limitations under the License.
Anna Bridge 186:707f6e361f3e 15 */
Anna Bridge 186:707f6e361f3e 16 #include <stddef.h>
Anna Bridge 186:707f6e361f3e 17 #include "us_ticker_api.h"
Anna Bridge 186:707f6e361f3e 18 #include "PeripheralNames.h"
Anna Bridge 186:707f6e361f3e 19 #define US_TICKER_TIMER1 CMSDK_DUALTIMER1
Anna Bridge 186:707f6e361f3e 20 #define US_TICKER_TIMER2 CMSDK_DUALTIMER2
Anna Bridge 186:707f6e361f3e 21 #define US_TICKER_TIMER_IRQn DUALTIMER_IRQn
Anna Bridge 186:707f6e361f3e 22
AnnaBridge 187:0387e8f68319 23 /** mbed OS HAL API defined us_ticker as an increment ticker
AnnaBridge 187:0387e8f68319 24 * MPS2 platform provided in SSE-200 are decrement tickers
AnnaBridge 187:0387e8f68319 25 * with interrupt fired counter reaches 0.
AnnaBridge 187:0387e8f68319 26 *
AnnaBridge 187:0387e8f68319 27 * So 2 Timers are used to construct mbed OS HAL ticker.
AnnaBridge 187:0387e8f68319 28 *
AnnaBridge 187:0387e8f68319 29 * TIMER1 is for counting, and returns inverted binary when read from it
AnnaBridge 187:0387e8f68319 30 * TIMER1 will be kept in free-running mode (default, and not generate interrupts)
AnnaBridge 187:0387e8f68319 31 *
AnnaBridge 187:0387e8f68319 32 * TIMER2 is for generating interrupts
AnnaBridge 187:0387e8f68319 33 * So TIMER2 is set to periodic mode, which start decrement counting form LOADVALUE generates interrupts at 0
AnnaBridge 187:0387e8f68319 34 * and TIMER2 also set into one-shot mode, which counter halts when is reaches 0
AnnaBridge 187:0387e8f68319 35 */
AnnaBridge 187:0387e8f68319 36
AnnaBridge 187:0387e8f68319 37 static int us_ticker_inited = 0;
Anna Bridge 186:707f6e361f3e 38
Anna Bridge 186:707f6e361f3e 39 void us_ticker_init(void)
Anna Bridge 186:707f6e361f3e 40 {
Anna Bridge 186:707f6e361f3e 41 if (us_ticker_inited) {
AnnaBridge 187:0387e8f68319 42 us_ticker_disable_interrupt();
Anna Bridge 186:707f6e361f3e 43 return;
Anna Bridge 186:707f6e361f3e 44 }
AnnaBridge 187:0387e8f68319 45
AnnaBridge 187:0387e8f68319 46 US_TICKER_TIMER1->TimerControl = 0x0ul; // disable TIMER1 and reset all control
AnnaBridge 187:0387e8f68319 47 US_TICKER_TIMER2->TimerControl = 0x0ul; // disable TIMER2 and reset all control
AnnaBridge 187:0387e8f68319 48
AnnaBridge 187:0387e8f68319 49 US_TICKER_TIMER1->TimerLoad = 0xFFFFFFFFul;
AnnaBridge 187:0387e8f68319 50 US_TICKER_TIMER2->TimerLoad = 0xFFFFFFFFul;
Anna Bridge 186:707f6e361f3e 51
AnnaBridge 187:0387e8f68319 52 US_TICKER_TIMER1->TimerControl |= CMSDK_DUALTIMER1_CTRL_SIZE_Msk; // set TIMER1 to 32 bit counter
AnnaBridge 187:0387e8f68319 53 US_TICKER_TIMER2->TimerControl |= CMSDK_DUALTIMER2_CTRL_SIZE_Msk; // set TIMER2 to 32 bit counter
Anna Bridge 186:707f6e361f3e 54
AnnaBridge 187:0387e8f68319 55 US_TICKER_TIMER1->TimerControl |= 0x1 << CMSDK_DUALTIMER1_CTRL_PRESCALE_Pos; // set TIMER1 with 4 stages prescale
AnnaBridge 187:0387e8f68319 56 US_TICKER_TIMER2->TimerControl |= 0x1 << CMSDK_DUALTIMER2_CTRL_PRESCALE_Pos; // set TIMER2 with 4 stages prescale
Anna Bridge 186:707f6e361f3e 57
AnnaBridge 187:0387e8f68319 58 US_TICKER_TIMER2->TimerControl |= CMSDK_DUALTIMER2_CTRL_MODE_Msk; // set TIMER2 periodic mode
AnnaBridge 187:0387e8f68319 59 US_TICKER_TIMER2->TimerControl |= CMSDK_DUALTIMER2_CTRL_ONESHOOT_Msk; // set TIMER2 one-shot mode
AnnaBridge 187:0387e8f68319 60
AnnaBridge 187:0387e8f68319 61 US_TICKER_TIMER1->TimerControl |= CMSDK_DUALTIMER1_CTRL_EN_Msk; // enable TIMER1 counter
Anna Bridge 186:707f6e361f3e 62
Anna Bridge 186:707f6e361f3e 63 NVIC_SetVector(US_TICKER_TIMER_IRQn, (uint32_t)us_ticker_irq_handler);
AnnaBridge 187:0387e8f68319 64 us_ticker_inited = 1;
AnnaBridge 187:0387e8f68319 65 }
AnnaBridge 187:0387e8f68319 66
AnnaBridge 187:0387e8f68319 67 void us_ticker_free(void)
AnnaBridge 187:0387e8f68319 68 {
AnnaBridge 187:0387e8f68319 69 US_TICKER_TIMER1->TimerControl &= ~CMSDK_DUALTIMER1_CTRL_EN_Msk; // disable TIMER1
AnnaBridge 187:0387e8f68319 70 US_TICKER_TIMER2->TimerControl &= ~CMSDK_DUALTIMER2_CTRL_EN_Msk; // disable TIMER2
AnnaBridge 187:0387e8f68319 71 us_ticker_disable_interrupt();
AnnaBridge 187:0387e8f68319 72 us_ticker_inited = 0;
Anna Bridge 186:707f6e361f3e 73 }
Anna Bridge 186:707f6e361f3e 74
Anna Bridge 186:707f6e361f3e 75 uint32_t us_ticker_read()
Anna Bridge 186:707f6e361f3e 76 {
AnnaBridge 187:0387e8f68319 77 return ~US_TICKER_TIMER1->TimerValue;
Anna Bridge 186:707f6e361f3e 78 }
Anna Bridge 186:707f6e361f3e 79
Anna Bridge 186:707f6e361f3e 80 void us_ticker_set_interrupt(timestamp_t timestamp)
Anna Bridge 186:707f6e361f3e 81 {
AnnaBridge 187:0387e8f68319 82 uint32_t delta = timestamp - us_ticker_read();
AnnaBridge 187:0387e8f68319 83 US_TICKER_TIMER2->TimerControl &= ~CMSDK_DUALTIMER2_CTRL_EN_Msk; // disable TIMER2
AnnaBridge 187:0387e8f68319 84 US_TICKER_TIMER2->TimerLoad = delta; // Set TIMER2 load value
AnnaBridge 187:0387e8f68319 85 US_TICKER_TIMER2->TimerControl |= CMSDK_DUALTIMER2_CTRL_INTEN_Msk; // enable TIMER2 interrupt
AnnaBridge 187:0387e8f68319 86 US_TICKER_TIMER2->TimerControl |= CMSDK_DUALTIMER2_CTRL_EN_Msk; // enable TIMER2 counter
AnnaBridge 187:0387e8f68319 87 NVIC_EnableIRQ(US_TICKER_TIMER_IRQn);
Anna Bridge 186:707f6e361f3e 88 }
Anna Bridge 186:707f6e361f3e 89
Anna Bridge 186:707f6e361f3e 90 void us_ticker_fire_interrupt(void)
Anna Bridge 186:707f6e361f3e 91 {
AnnaBridge 187:0387e8f68319 92 NVIC_EnableIRQ(US_TICKER_TIMER_IRQn);
Anna Bridge 186:707f6e361f3e 93 NVIC_SetPendingIRQ(US_TICKER_TIMER_IRQn);
Anna Bridge 186:707f6e361f3e 94 }
Anna Bridge 186:707f6e361f3e 95
Anna Bridge 186:707f6e361f3e 96
Anna Bridge 186:707f6e361f3e 97 void us_ticker_disable_interrupt(void)
Anna Bridge 186:707f6e361f3e 98 {
AnnaBridge 187:0387e8f68319 99 US_TICKER_TIMER2->TimerControl &= ~CMSDK_DUALTIMER2_CTRL_INTEN_Msk;
AnnaBridge 187:0387e8f68319 100 US_TICKER_TIMER2->TimerControl &= ~CMSDK_DUALTIMER2_CTRL_EN_Msk; // disable TIMER2
AnnaBridge 187:0387e8f68319 101 NVIC_DisableIRQ(US_TICKER_TIMER_IRQn);
Anna Bridge 186:707f6e361f3e 102 }
Anna Bridge 186:707f6e361f3e 103
Anna Bridge 186:707f6e361f3e 104 void us_ticker_clear_interrupt(void)
Anna Bridge 186:707f6e361f3e 105 {
AnnaBridge 187:0387e8f68319 106 US_TICKER_TIMER2->TimerIntClr = CMSDK_DUALTIMER2_INTCLR_Msk;
AnnaBridge 187:0387e8f68319 107 }
Anna Bridge 186:707f6e361f3e 108
AnnaBridge 187:0387e8f68319 109 const ticker_info_t *us_ticker_get_info(void)
AnnaBridge 187:0387e8f68319 110 {
AnnaBridge 187:0387e8f68319 111 static const ticker_info_t info = {
AnnaBridge 187:0387e8f68319 112 1562500, // 4 stages prescaled from 25MHz (dived by 16)
AnnaBridge 187:0387e8f68319 113 32 // 32 bit counter
AnnaBridge 187:0387e8f68319 114 };
AnnaBridge 187:0387e8f68319 115 return &info;
Anna Bridge 186:707f6e361f3e 116 }