mbed official / mbed-dev

mbed library sources. Supersedes mbed-src.

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

targets/TARGET_NUVOTON/TARGET_NANO100/lp_ticker.c@182:a56a73fd2a6f, 2018-03-20 (annotated)

Committer:
AnnaBridge
Date:
Tue Mar 20 16:56:18 2018 +0000
Revision:
182:a56a73fd2a6f
Parent:
176:447f873cad2f
Child:
184:08ed48f1de7f
mbed-dev library. Release version 160

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 174:b96e65c34a4d 1 /* mbed Microcontroller Library
AnnaBridge 174:b96e65c34a4d 2 * Copyright (c) 2015-2017 Nuvoton
AnnaBridge 174:b96e65c34a4d 3 *
AnnaBridge 174:b96e65c34a4d 4 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 174:b96e65c34a4d 5 * you may not use this file except in compliance with the License.
AnnaBridge 174:b96e65c34a4d 6 * You may obtain a copy of the License at
AnnaBridge 174:b96e65c34a4d 7 *
AnnaBridge 174:b96e65c34a4d 8 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 174:b96e65c34a4d 9 *
AnnaBridge 174:b96e65c34a4d 10 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 174:b96e65c34a4d 11 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 174:b96e65c34a4d 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 174:b96e65c34a4d 13 * See the License for the specific language governing permissions and
AnnaBridge 174:b96e65c34a4d 14 * limitations under the License.
AnnaBridge 174:b96e65c34a4d 15 */
AnnaBridge 182:a56a73fd2a6f 16
AnnaBridge 174:b96e65c34a4d 17 #include "lp_ticker_api.h"
AnnaBridge 174:b96e65c34a4d 18
AnnaBridge 174:b96e65c34a4d 19 #if DEVICE_LOWPOWERTIMER
AnnaBridge 174:b96e65c34a4d 20
AnnaBridge 174:b96e65c34a4d 21 #include "sleep_api.h"
AnnaBridge 182:a56a73fd2a6f 22 #include "mbed_wait_api.h"
AnnaBridge 182:a56a73fd2a6f 23 #include "mbed_assert.h"
AnnaBridge 174:b96e65c34a4d 24 #include "nu_modutil.h"
AnnaBridge 174:b96e65c34a4d 25 #include "nu_miscutil.h"
AnnaBridge 174:b96e65c34a4d 26
AnnaBridge 182:a56a73fd2a6f 27 /* Micro seconds per second */
AnnaBridge 182:a56a73fd2a6f 28 #define NU_US_PER_SEC 1000000
AnnaBridge 182:a56a73fd2a6f 29 /* Timer clock per lp_ticker tick */
AnnaBridge 182:a56a73fd2a6f 30 #define NU_TMRCLK_PER_TICK 1
AnnaBridge 182:a56a73fd2a6f 31 /* Timer clock per second */
AnnaBridge 182:a56a73fd2a6f 32 #define NU_TMRCLK_PER_SEC (__LXT)
AnnaBridge 182:a56a73fd2a6f 33 /* Timer max counter bit size */
AnnaBridge 182:a56a73fd2a6f 34 #define NU_TMR_MAXCNT_BITSIZE 24
AnnaBridge 182:a56a73fd2a6f 35 /* Timer max counter */
AnnaBridge 182:a56a73fd2a6f 36 #define NU_TMR_MAXCNT ((1 << NU_TMR_MAXCNT_BITSIZE) - 1)
AnnaBridge 174:b96e65c34a4d 37
AnnaBridge 182:a56a73fd2a6f 38 /* NOTE: Don't add static modifier here. These IRQ handler symbols are for linking.
AnnaBridge 182:a56a73fd2a6f 39 Vector table relocation is not actually supported for low-resource target. */
AnnaBridge 182:a56a73fd2a6f 40 void TMR1_IRQHandler(void);
AnnaBridge 174:b96e65c34a4d 41
AnnaBridge 182:a56a73fd2a6f 42 /* NOTE: To wake the system from power down mode, timer clock source must be ether LXT or LIRC. */
AnnaBridge 182:a56a73fd2a6f 43 static const struct nu_modinit_s timer1_modinit = {TIMER_1, TMR1_MODULE, CLK_CLKSEL1_TMR1_S_LXT, 0, TMR1_RST, TMR1_IRQn, (void *) TMR1_IRQHandler};
AnnaBridge 182:a56a73fd2a6f 44
AnnaBridge 182:a56a73fd2a6f 45 #define TIMER_MODINIT timer1_modinit
AnnaBridge 182:a56a73fd2a6f 46
AnnaBridge 182:a56a73fd2a6f 47 static int ticker_inited = 0;
AnnaBridge 174:b96e65c34a4d 48
AnnaBridge 174:b96e65c34a4d 49 #define TMR_CMP_MIN 2
AnnaBridge 174:b96e65c34a4d 50 #define TMR_CMP_MAX 0xFFFFFFu
AnnaBridge 174:b96e65c34a4d 51
AnnaBridge 174:b96e65c34a4d 52 void lp_ticker_init(void)
AnnaBridge 174:b96e65c34a4d 53 {
AnnaBridge 182:a56a73fd2a6f 54 if (ticker_inited) {
AnnaBridge 174:b96e65c34a4d 55 return;
AnnaBridge 174:b96e65c34a4d 56 }
AnnaBridge 182:a56a73fd2a6f 57 ticker_inited = 1;
AnnaBridge 174:b96e65c34a4d 58
AnnaBridge 174:b96e65c34a4d 59 // Reset module
AnnaBridge 182:a56a73fd2a6f 60 SYS_ResetModule(TIMER_MODINIT.rsetidx);
AnnaBridge 182:a56a73fd2a6f 61
AnnaBridge 174:b96e65c34a4d 62 // Select IP clock source
AnnaBridge 182:a56a73fd2a6f 63 CLK_SetModuleClock(TIMER_MODINIT.clkidx, TIMER_MODINIT.clksrc, TIMER_MODINIT.clkdiv);
AnnaBridge 182:a56a73fd2a6f 64
AnnaBridge 174:b96e65c34a4d 65 // Enable IP clock
AnnaBridge 182:a56a73fd2a6f 66 CLK_EnableModuleClock(TIMER_MODINIT.clkidx);
AnnaBridge 174:b96e65c34a4d 67
AnnaBridge 174:b96e65c34a4d 68 // Configure clock
AnnaBridge 182:a56a73fd2a6f 69 uint32_t clk_timer = TIMER_GetModuleClock((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 182:a56a73fd2a6f 70 uint32_t prescale_timer = clk_timer / NU_TMRCLK_PER_SEC - 1;
AnnaBridge 182:a56a73fd2a6f 71 MBED_ASSERT((prescale_timer != (uint32_t) -1) && prescale_timer <= 127);
AnnaBridge 182:a56a73fd2a6f 72 MBED_ASSERT((clk_timer % NU_TMRCLK_PER_SEC) == 0);
AnnaBridge 182:a56a73fd2a6f 73 uint32_t cmp_timer = TMR_CMP_MAX;
AnnaBridge 182:a56a73fd2a6f 74 MBED_ASSERT(cmp_timer >= TMR_CMP_MIN && cmp_timer <= TMR_CMP_MAX);
AnnaBridge 174:b96e65c34a4d 75 // Continuous mode
AnnaBridge 182:a56a73fd2a6f 76 ((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname))->CTL = TIMER_CONTINUOUS_MODE;
AnnaBridge 182:a56a73fd2a6f 77 ((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname))->PRECNT = prescale_timer;
AnnaBridge 182:a56a73fd2a6f 78 ((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname))->CMPR = cmp_timer;
AnnaBridge 182:a56a73fd2a6f 79
AnnaBridge 174:b96e65c34a4d 80 // Set vector
AnnaBridge 182:a56a73fd2a6f 81 NVIC_SetVector(TIMER_MODINIT.irq_n, (uint32_t) TIMER_MODINIT.var);
AnnaBridge 182:a56a73fd2a6f 82
AnnaBridge 182:a56a73fd2a6f 83 NVIC_EnableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 174:b96e65c34a4d 84
AnnaBridge 182:a56a73fd2a6f 85 TIMER_EnableInt((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 182:a56a73fd2a6f 86 TIMER_EnableWakeup((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 182:a56a73fd2a6f 87 /* NOTE: When engine is clocked by low power clock source (LXT/LIRC), we need to wait for 3 engine clocks. */
AnnaBridge 182:a56a73fd2a6f 88 wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
AnnaBridge 182:a56a73fd2a6f 89 TIMER_Start((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 174:b96e65c34a4d 90 }
AnnaBridge 174:b96e65c34a4d 91
AnnaBridge 174:b96e65c34a4d 92 timestamp_t lp_ticker_read()
AnnaBridge 182:a56a73fd2a6f 93 {
AnnaBridge 182:a56a73fd2a6f 94 if (! ticker_inited) {
AnnaBridge 174:b96e65c34a4d 95 lp_ticker_init();
AnnaBridge 174:b96e65c34a4d 96 }
AnnaBridge 174:b96e65c34a4d 97
AnnaBridge 182:a56a73fd2a6f 98 TIMER_T * timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 182:a56a73fd2a6f 99
AnnaBridge 182:a56a73fd2a6f 100 return (TIMER_GetCounter(timer_base) / NU_TMRCLK_PER_TICK);
AnnaBridge 174:b96e65c34a4d 101 }
AnnaBridge 174:b96e65c34a4d 102
AnnaBridge 174:b96e65c34a4d 103 void lp_ticker_set_interrupt(timestamp_t timestamp)
AnnaBridge 174:b96e65c34a4d 104 {
AnnaBridge 182:a56a73fd2a6f 105 /* In continuous mode, counter will be reset to zero with the following sequence:
AnnaBridge 182:a56a73fd2a6f 106 * 1. Stop counting
AnnaBridge 182:a56a73fd2a6f 107 * 2. Configure new CMP value
AnnaBridge 182:a56a73fd2a6f 108 * 3. Restart counting
AnnaBridge 182:a56a73fd2a6f 109 *
AnnaBridge 182:a56a73fd2a6f 110 * This behavior is not what we want. To fix it, we could configure new CMP value
AnnaBridge 182:a56a73fd2a6f 111 * without stopping counting first.
AnnaBridge 182:a56a73fd2a6f 112 */
AnnaBridge 182:a56a73fd2a6f 113 TIMER_T * timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 174:b96e65c34a4d 114
AnnaBridge 182:a56a73fd2a6f 115 /* NOTE: Because H/W timer requests min compare value, our implementation would have alarm delay of
AnnaBridge 182:a56a73fd2a6f 116 * (TMR_CMP_MIN - interval_clk) clocks when interval_clk is between [1, TMR_CMP_MIN). */
AnnaBridge 182:a56a73fd2a6f 117 uint32_t cmp_timer = timestamp * NU_TMRCLK_PER_TICK;
AnnaBridge 182:a56a73fd2a6f 118 cmp_timer = NU_CLAMP(cmp_timer, TMR_CMP_MIN, TMR_CMP_MAX);
AnnaBridge 182:a56a73fd2a6f 119 timer_base->CMPR = cmp_timer;
AnnaBridge 182:a56a73fd2a6f 120
AnnaBridge 182:a56a73fd2a6f 121 /* NOTE: When engine is clocked by low power clock source (LXT/LIRC), we need to wait for 3 engine clocks. */
AnnaBridge 182:a56a73fd2a6f 122 wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
AnnaBridge 182:a56a73fd2a6f 123 TIMER_Start(timer_base);
AnnaBridge 174:b96e65c34a4d 124 }
AnnaBridge 174:b96e65c34a4d 125
AnnaBridge 174:b96e65c34a4d 126 void lp_ticker_disable_interrupt(void)
AnnaBridge 174:b96e65c34a4d 127 {
AnnaBridge 182:a56a73fd2a6f 128 TIMER_DisableInt((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 174:b96e65c34a4d 129 }
AnnaBridge 174:b96e65c34a4d 130
AnnaBridge 174:b96e65c34a4d 131 void lp_ticker_clear_interrupt(void)
AnnaBridge 174:b96e65c34a4d 132 {
AnnaBridge 182:a56a73fd2a6f 133 TIMER_ClearIntFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 174:b96e65c34a4d 134 }
AnnaBridge 174:b96e65c34a4d 135
AnnaBridge 182:a56a73fd2a6f 136 void lp_ticker_fire_interrupt(void)
AnnaBridge 174:b96e65c34a4d 137 {
AnnaBridge 182:a56a73fd2a6f 138 // NOTE: This event was in the past. Set the interrupt as pending, but don't process it here.
AnnaBridge 182:a56a73fd2a6f 139 // This prevents a recursive loop under heavy load which can lead to a stack overflow.
AnnaBridge 182:a56a73fd2a6f 140 NVIC_SetPendingIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 174:b96e65c34a4d 141 }
AnnaBridge 174:b96e65c34a4d 142
AnnaBridge 182:a56a73fd2a6f 143 const ticker_info_t* lp_ticker_get_info()
AnnaBridge 174:b96e65c34a4d 144 {
AnnaBridge 182:a56a73fd2a6f 145 static const ticker_info_t info = {
AnnaBridge 182:a56a73fd2a6f 146 NU_TMRCLK_PER_SEC / NU_TMRCLK_PER_TICK,
AnnaBridge 182:a56a73fd2a6f 147 NU_TMR_MAXCNT_BITSIZE
AnnaBridge 182:a56a73fd2a6f 148 };
AnnaBridge 182:a56a73fd2a6f 149 return &info;
AnnaBridge 182:a56a73fd2a6f 150 }
AnnaBridge 182:a56a73fd2a6f 151
AnnaBridge 182:a56a73fd2a6f 152 void TMR1_IRQHandler(void)
AnnaBridge 182:a56a73fd2a6f 153 {
AnnaBridge 182:a56a73fd2a6f 154 TIMER_ClearIntFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 182:a56a73fd2a6f 155 TIMER_ClearWakeupFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 174:b96e65c34a4d 156
AnnaBridge 182:a56a73fd2a6f 157 // NOTE: lp_ticker_set_interrupt() may get called in lp_ticker_irq_handler();
AnnaBridge 182:a56a73fd2a6f 158 lp_ticker_irq_handler();
AnnaBridge 174:b96e65c34a4d 159 }
AnnaBridge 182:a56a73fd2a6f 160
AnnaBridge 174:b96e65c34a4d 161 #endif