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targets/TARGET_NUVOTON/TARGET_NUC472/us_ticker.c@188:60408c49b6d4, 2018-09-20 (annotated)

Committer:
WaleedElmughrabi
Date:
Thu Sep 20 16:11:23 2018 +0000
Revision:
188:60408c49b6d4
Parent:
187:0387e8f68319 
Fork modified for BG96 error

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 149:156823d33999 1 /* mbed Microcontroller Library
<> 149:156823d33999 2 * Copyright (c) 2015-2016 Nuvoton
<> 149:156823d33999 3 *
<> 149:156823d33999 4 * Licensed under the Apache License, Version 2.0 (the "License");
<> 149:156823d33999 5 * you may not use this file except in compliance with the License.
<> 149:156823d33999 6 * You may obtain a copy of the License at
<> 149:156823d33999 7 *
<> 149:156823d33999 8 * http://www.apache.org/licenses/LICENSE-2.0
<> 149:156823d33999 9 *
<> 149:156823d33999 10 * Unless required by applicable law or agreed to in writing, software
<> 149:156823d33999 11 * distributed under the License is distributed on an "AS IS" BASIS,
<> 149:156823d33999 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 149:156823d33999 13 * See the License for the specific language governing permissions and
<> 149:156823d33999 14 * limitations under the License.
<> 149:156823d33999 15 */
AnnaBridge 182:a56a73fd2a6f 16
<> 149:156823d33999 17 #include "us_ticker_api.h"
AnnaBridge 187:0387e8f68319 18
AnnaBridge 187:0387e8f68319 19 #if DEVICE_USTICKER
AnnaBridge 187:0387e8f68319 20
<> 149:156823d33999 21 #include "sleep_api.h"
<> 149:156823d33999 22 #include "mbed_assert.h"
<> 149:156823d33999 23 #include "nu_modutil.h"
<> 149:156823d33999 24 #include "nu_miscutil.h"
<> 149:156823d33999 25
AnnaBridge 182:a56a73fd2a6f 26 /* Micro seconds per second */
AnnaBridge 182:a56a73fd2a6f 27 #define NU_US_PER_SEC 1000000
AnnaBridge 182:a56a73fd2a6f 28 /* Timer clock per us_ticker tick */
AnnaBridge 182:a56a73fd2a6f 29 #define NU_TMRCLK_PER_TICK 1
AnnaBridge 182:a56a73fd2a6f 30 /* Timer clock per second */
AnnaBridge 182:a56a73fd2a6f 31 #define NU_TMRCLK_PER_SEC (1000 * 1000)
AnnaBridge 182:a56a73fd2a6f 32 /* Timer max counter bit size */
AnnaBridge 182:a56a73fd2a6f 33 #define NU_TMR_MAXCNT_BITSIZE 24
AnnaBridge 182:a56a73fd2a6f 34 /* Timer max counter */
AnnaBridge 182:a56a73fd2a6f 35 #define NU_TMR_MAXCNT ((1 << NU_TMR_MAXCNT_BITSIZE) - 1)
<> 149:156823d33999 36
<> 149:156823d33999 37 static void tmr0_vec(void);
<> 149:156823d33999 38
AnnaBridge 182:a56a73fd2a6f 39 static const struct nu_modinit_s timer0_modinit = {TIMER_0, TMR0_MODULE, CLK_CLKSEL1_TMR0SEL_PCLK, 0, TMR0_RST, TMR0_IRQn, (void *) tmr0_vec};
<> 149:156823d33999 40
AnnaBridge 182:a56a73fd2a6f 41 #define TIMER_MODINIT timer0_modinit
AnnaBridge 182:a56a73fd2a6f 42
AnnaBridge 187:0387e8f68319 43 /* Track ticker status */
AnnaBridge 187:0387e8f68319 44 static volatile uint16_t ticker_inited = 0;
<> 149:156823d33999 45
<> 149:156823d33999 46 #define TMR_CMP_MIN 2
<> 149:156823d33999 47 #define TMR_CMP_MAX 0xFFFFFFu
<> 149:156823d33999 48
<> 149:156823d33999 49 void us_ticker_init(void)
<> 149:156823d33999 50 {
AnnaBridge 182:a56a73fd2a6f 51 if (ticker_inited) {
AnnaBridge 187:0387e8f68319 52 /* By HAL spec, ticker_init allows the ticker to keep counting and disables the
AnnaBridge 187:0387e8f68319 53 * ticker interrupt. */
AnnaBridge 187:0387e8f68319 54 us_ticker_disable_interrupt();
AnnaBridge 187:0387e8f68319 55 us_ticker_clear_interrupt();
AnnaBridge 187:0387e8f68319 56 NVIC_ClearPendingIRQ(TIMER_MODINIT.irq_n);
<> 149:156823d33999 57 return;
<> 149:156823d33999 58 }
AnnaBridge 182:a56a73fd2a6f 59 ticker_inited = 1;
AnnaBridge 182:a56a73fd2a6f 60
<> 149:156823d33999 61 // Reset IP
AnnaBridge 182:a56a73fd2a6f 62 SYS_ResetModule(TIMER_MODINIT.rsetidx);
AnnaBridge 182:a56a73fd2a6f 63
<> 149:156823d33999 64 // Select IP clock source
AnnaBridge 182:a56a73fd2a6f 65 CLK_SetModuleClock(TIMER_MODINIT.clkidx, TIMER_MODINIT.clksrc, TIMER_MODINIT.clkdiv);
AnnaBridge 182:a56a73fd2a6f 66
<> 149:156823d33999 67 // Enable IP clock
AnnaBridge 182:a56a73fd2a6f 68 CLK_EnableModuleClock(TIMER_MODINIT.clkidx);
<> 149:156823d33999 69
AnnaBridge 184:08ed48f1de7f 70 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 184:08ed48f1de7f 71
<> 149:156823d33999 72 // Timer for normal counter
AnnaBridge 184:08ed48f1de7f 73 uint32_t clk_timer = TIMER_GetModuleClock(timer_base);
AnnaBridge 182:a56a73fd2a6f 74 uint32_t prescale_timer = clk_timer / NU_TMRCLK_PER_SEC - 1;
AnnaBridge 182:a56a73fd2a6f 75 MBED_ASSERT((prescale_timer != (uint32_t) -1) && prescale_timer <= 127);
AnnaBridge 182:a56a73fd2a6f 76 MBED_ASSERT((clk_timer % NU_TMRCLK_PER_SEC) == 0);
AnnaBridge 182:a56a73fd2a6f 77 uint32_t cmp_timer = TMR_CMP_MAX;
AnnaBridge 182:a56a73fd2a6f 78 MBED_ASSERT(cmp_timer >= TMR_CMP_MIN && cmp_timer <= TMR_CMP_MAX);
AnnaBridge 184:08ed48f1de7f 79 timer_base->CTL = TIMER_CONTINUOUS_MODE | prescale_timer | TIMER_CTL_CNTDATEN_Msk;
AnnaBridge 184:08ed48f1de7f 80 timer_base->CMP = cmp_timer;
AnnaBridge 182:a56a73fd2a6f 81
AnnaBridge 182:a56a73fd2a6f 82 NVIC_SetVector(TIMER_MODINIT.irq_n, (uint32_t) TIMER_MODINIT.var);
AnnaBridge 182:a56a73fd2a6f 83
AnnaBridge 187:0387e8f68319 84 NVIC_DisableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 182:a56a73fd2a6f 85
AnnaBridge 184:08ed48f1de7f 86 TIMER_EnableInt(timer_base);
AnnaBridge 184:08ed48f1de7f 87
AnnaBridge 184:08ed48f1de7f 88 TIMER_Start(timer_base);
AnnaBridge 184:08ed48f1de7f 89 /* Wait for timer to start counting and raise active flag */
AnnaBridge 184:08ed48f1de7f 90 while(! (timer_base->CTL & TIMER_CTL_ACTSTS_Msk));
<> 149:156823d33999 91 }
<> 149:156823d33999 92
AnnaBridge 187:0387e8f68319 93 void us_ticker_free(void)
AnnaBridge 187:0387e8f68319 94 {
AnnaBridge 187:0387e8f68319 95 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 187:0387e8f68319 96
AnnaBridge 187:0387e8f68319 97 /* Stop counting */
AnnaBridge 187:0387e8f68319 98 TIMER_Stop(timer_base);
AnnaBridge 187:0387e8f68319 99
AnnaBridge 187:0387e8f68319 100 /* Wait for timer to stop counting and unset active flag */
AnnaBridge 187:0387e8f68319 101 while((timer_base->CTL & TIMER_CTL_ACTSTS_Msk));
AnnaBridge 187:0387e8f68319 102
AnnaBridge 187:0387e8f68319 103 /* Disable interrupt */
AnnaBridge 187:0387e8f68319 104 TIMER_DisableInt(timer_base);
AnnaBridge 187:0387e8f68319 105 NVIC_DisableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 106
AnnaBridge 187:0387e8f68319 107 /* Disable IP clock */
AnnaBridge 187:0387e8f68319 108 CLK_DisableModuleClock(TIMER_MODINIT.clkidx);
AnnaBridge 187:0387e8f68319 109
AnnaBridge 187:0387e8f68319 110 ticker_inited = 0;
AnnaBridge 187:0387e8f68319 111 }
AnnaBridge 187:0387e8f68319 112
<> 149:156823d33999 113 uint32_t us_ticker_read()
<> 149:156823d33999 114 {
AnnaBridge 182:a56a73fd2a6f 115 if (! ticker_inited) {
<> 149:156823d33999 116 us_ticker_init();
<> 149:156823d33999 117 }
<> 149:156823d33999 118
AnnaBridge 184:08ed48f1de7f 119 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
<> 149:156823d33999 120
AnnaBridge 182:a56a73fd2a6f 121 return (TIMER_GetCounter(timer_base) / NU_TMRCLK_PER_TICK);
<> 149:156823d33999 122 }
<> 149:156823d33999 123
<> 149:156823d33999 124 void us_ticker_set_interrupt(timestamp_t timestamp)
<> 149:156823d33999 125 {
AnnaBridge 182:a56a73fd2a6f 126 /* In continuous mode, counter will be reset to zero with the following sequence:
AnnaBridge 182:a56a73fd2a6f 127 * 1. Stop counting
AnnaBridge 182:a56a73fd2a6f 128 * 2. Configure new CMP value
AnnaBridge 182:a56a73fd2a6f 129 * 3. Restart counting
AnnaBridge 182:a56a73fd2a6f 130 *
AnnaBridge 182:a56a73fd2a6f 131 * This behavior is not what we want. To fix it, we could configure new CMP value
AnnaBridge 182:a56a73fd2a6f 132 * without stopping counting first.
AnnaBridge 182:a56a73fd2a6f 133 */
AnnaBridge 184:08ed48f1de7f 134 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 182:a56a73fd2a6f 135
AnnaBridge 182:a56a73fd2a6f 136 /* NOTE: Because H/W timer requests min compare value, our implementation would have alarm delay of
AnnaBridge 182:a56a73fd2a6f 137 * (TMR_CMP_MIN - interval_clk) clocks when interval_clk is between [1, TMR_CMP_MIN). */
AnnaBridge 182:a56a73fd2a6f 138 uint32_t cmp_timer = timestamp * NU_TMRCLK_PER_TICK;
AnnaBridge 182:a56a73fd2a6f 139 cmp_timer = NU_CLAMP(cmp_timer, TMR_CMP_MIN, TMR_CMP_MAX);
AnnaBridge 182:a56a73fd2a6f 140 timer_base->CMP = cmp_timer;
AnnaBridge 187:0387e8f68319 141
AnnaBridge 187:0387e8f68319 142 /* We can call ticker_irq_handler now. */
AnnaBridge 187:0387e8f68319 143 NVIC_EnableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 182:a56a73fd2a6f 144 }
AnnaBridge 182:a56a73fd2a6f 145
AnnaBridge 182:a56a73fd2a6f 146 void us_ticker_disable_interrupt(void)
AnnaBridge 182:a56a73fd2a6f 147 {
AnnaBridge 187:0387e8f68319 148 /* We cannot call ticker_irq_handler now. */
AnnaBridge 187:0387e8f68319 149 NVIC_DisableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 182:a56a73fd2a6f 150 }
AnnaBridge 182:a56a73fd2a6f 151
AnnaBridge 182:a56a73fd2a6f 152 void us_ticker_clear_interrupt(void)
AnnaBridge 182:a56a73fd2a6f 153 {
AnnaBridge 182:a56a73fd2a6f 154 TIMER_ClearIntFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 174:b96e65c34a4d 155 }
AnnaBridge 174:b96e65c34a4d 156
AnnaBridge 174:b96e65c34a4d 157 void us_ticker_fire_interrupt(void)
AnnaBridge 174:b96e65c34a4d 158 {
AnnaBridge 182:a56a73fd2a6f 159 // NOTE: This event was in the past. Set the interrupt as pending, but don't process it here.
AnnaBridge 182:a56a73fd2a6f 160 // This prevents a recursive loop under heavy load which can lead to a stack overflow.
AnnaBridge 182:a56a73fd2a6f 161 NVIC_SetPendingIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 162
AnnaBridge 187:0387e8f68319 163 /* We can call ticker_irq_handler now. */
AnnaBridge 187:0387e8f68319 164 NVIC_EnableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 182:a56a73fd2a6f 165 }
AnnaBridge 182:a56a73fd2a6f 166
AnnaBridge 182:a56a73fd2a6f 167 const ticker_info_t* us_ticker_get_info()
AnnaBridge 182:a56a73fd2a6f 168 {
AnnaBridge 182:a56a73fd2a6f 169 static const ticker_info_t info = {
AnnaBridge 182:a56a73fd2a6f 170 NU_TMRCLK_PER_SEC / NU_TMRCLK_PER_TICK,
AnnaBridge 182:a56a73fd2a6f 171 NU_TMR_MAXCNT_BITSIZE
AnnaBridge 182:a56a73fd2a6f 172 };
AnnaBridge 182:a56a73fd2a6f 173 return &info;
<> 149:156823d33999 174 }
<> 149:156823d33999 175
<> 149:156823d33999 176 static void tmr0_vec(void)
<> 149:156823d33999 177 {
AnnaBridge 187:0387e8f68319 178 us_ticker_clear_interrupt();
AnnaBridge 187:0387e8f68319 179
AnnaBridge 182:a56a73fd2a6f 180 // NOTE: us_ticker_set_interrupt() may get called in us_ticker_irq_handler();
AnnaBridge 182:a56a73fd2a6f 181 us_ticker_irq_handler();
<> 149:156823d33999 182 }
AnnaBridge 187:0387e8f68319 183
AnnaBridge 187:0387e8f68319 184 #endif