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mbed library sources. Supersedes mbed-src.

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targets/TARGET_NUVOTON/TARGET_M2351/lp_ticker.c@189:f392fc9709a3, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 22:31:08 2019 +0000
Revision:
189:f392fc9709a3
Parent:
188:bcfe06ba3d64 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 187:0387e8f68319 1 /* mbed Microcontroller Library
AnnaBridge 187:0387e8f68319 2 * Copyright (c) 2017-2018 Nuvoton
AnnaBridge 187:0387e8f68319 3 *
AnnaBridge 187:0387e8f68319 4 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 187:0387e8f68319 5 * you may not use this file except in compliance with the License.
AnnaBridge 187:0387e8f68319 6 * You may obtain a copy of the License at
AnnaBridge 187:0387e8f68319 7 *
AnnaBridge 187:0387e8f68319 8 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 187:0387e8f68319 9 *
AnnaBridge 187:0387e8f68319 10 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 187:0387e8f68319 11 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 187:0387e8f68319 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 187:0387e8f68319 13 * See the License for the specific language governing permissions and
AnnaBridge 187:0387e8f68319 14 * limitations under the License.
AnnaBridge 187:0387e8f68319 15 */
AnnaBridge 187:0387e8f68319 16
AnnaBridge 187:0387e8f68319 17 #include "lp_ticker_api.h"
AnnaBridge 187:0387e8f68319 18
AnnaBridge 187:0387e8f68319 19 #if DEVICE_LPTICKER
AnnaBridge 187:0387e8f68319 20
AnnaBridge 187:0387e8f68319 21 #include "sleep_api.h"
AnnaBridge 187:0387e8f68319 22 #include "mbed_assert.h"
AnnaBridge 187:0387e8f68319 23 #include "nu_modutil.h"
AnnaBridge 188:bcfe06ba3d64 24 #include "nu_timer.h"
AnnaBridge 187:0387e8f68319 25 #include "nu_miscutil.h"
AnnaBridge 187:0387e8f68319 26 #include "partition_M2351.h"
AnnaBridge 187:0387e8f68319 27
AnnaBridge 187:0387e8f68319 28 /* We have the following policy for configuring security state of TIMER for us_ticer/lp_ticker:
AnnaBridge 187:0387e8f68319 29 *
AnnaBridge 187:0387e8f68319 30 * TIMER0: Hard-wired to secure and used for secure us_ticer
AnnaBridge 187:0387e8f68319 31 * TIMER1: Hard-wired to secure and used for secure lp_ticer
AnnaBridge 187:0387e8f68319 32 * TIMER2: Configured to non-secure and used for non-secure us_ticer
AnnaBridge 187:0387e8f68319 33 * TIMER3: Configured to non-secure and used for non-secure lp_ticer
AnnaBridge 187:0387e8f68319 34 */
AnnaBridge 187:0387e8f68319 35 #if (! defined(SCU_INIT_PNSSET2_VAL)) || (! (SCU_INIT_PNSSET2_VAL & (1 << 17)))
AnnaBridge 187:0387e8f68319 36 #error("TIMER2/3 must be configured to non-secure for non-secure us_ticker/lp_ticker.")
AnnaBridge 187:0387e8f68319 37 #endif
AnnaBridge 187:0387e8f68319 38
AnnaBridge 187:0387e8f68319 39 /* Micro seconds per second */
AnnaBridge 187:0387e8f68319 40 #define NU_US_PER_SEC 1000000
AnnaBridge 187:0387e8f68319 41 /* Timer clock per lp_ticker tick */
AnnaBridge 187:0387e8f68319 42 #define NU_TMRCLK_PER_TICK 1
AnnaBridge 187:0387e8f68319 43 /* Timer clock per second */
AnnaBridge 187:0387e8f68319 44 #define NU_TMRCLK_PER_SEC (__LXT)
AnnaBridge 187:0387e8f68319 45 /* Timer max counter bit size */
AnnaBridge 187:0387e8f68319 46 #define NU_TMR_MAXCNT_BITSIZE 24
AnnaBridge 187:0387e8f68319 47 /* Timer max counter */
AnnaBridge 187:0387e8f68319 48 #define NU_TMR_MAXCNT ((1 << NU_TMR_MAXCNT_BITSIZE) - 1)
AnnaBridge 187:0387e8f68319 49
AnnaBridge 187:0387e8f68319 50 #if defined (__ARM_FEATURE_CMSE) && (__ARM_FEATURE_CMSE == 3U)
AnnaBridge 187:0387e8f68319 51
AnnaBridge 187:0387e8f68319 52 static void tmr1_vec(void);
AnnaBridge 187:0387e8f68319 53
AnnaBridge 187:0387e8f68319 54 /* NOTE: To wake the system from power down mode, timer clock source must be ether LXT or LIRC. */
AnnaBridge 187:0387e8f68319 55 static const struct nu_modinit_s timer1_modinit = {TIMER_1, TMR1_MODULE, CLK_CLKSEL1_TMR1SEL_LXT, 0, TMR1_RST, TMR1_IRQn, (void *) tmr1_vec};
AnnaBridge 187:0387e8f68319 56
AnnaBridge 187:0387e8f68319 57 #define TIMER_MODINIT timer1_modinit
AnnaBridge 187:0387e8f68319 58
AnnaBridge 187:0387e8f68319 59 #else
AnnaBridge 187:0387e8f68319 60
AnnaBridge 187:0387e8f68319 61 static void tmr3_vec(void);
AnnaBridge 187:0387e8f68319 62
AnnaBridge 187:0387e8f68319 63 /* NOTE: To wake the system from power down mode, timer clock source must be ether LXT or LIRC. */
AnnaBridge 187:0387e8f68319 64 static const struct nu_modinit_s timer3_modinit = {TIMER_3, TMR3_MODULE, CLK_CLKSEL1_TMR3SEL_LXT, 0, TMR3_RST, TMR3_IRQn, (void *) tmr3_vec};
AnnaBridge 187:0387e8f68319 65
AnnaBridge 187:0387e8f68319 66 #define TIMER_MODINIT timer3_modinit
AnnaBridge 187:0387e8f68319 67
AnnaBridge 187:0387e8f68319 68 #endif
AnnaBridge 187:0387e8f68319 69
AnnaBridge 187:0387e8f68319 70 /* Timer interrupt enable/disable
AnnaBridge 187:0387e8f68319 71 *
AnnaBridge 187:0387e8f68319 72 * Because Timer interrupt enable/disable (TIMER_EnableInt/TIMER_DisableInt) needs wait for lp_ticker,
AnnaBridge 187:0387e8f68319 73 * we call NVIC_DisableIRQ/NVIC_EnableIRQ instead.
AnnaBridge 187:0387e8f68319 74 */
AnnaBridge 187:0387e8f68319 75
AnnaBridge 187:0387e8f68319 76 /* Track ticker status */
AnnaBridge 187:0387e8f68319 77 static volatile uint16_t ticker_inited = 0;
AnnaBridge 187:0387e8f68319 78
AnnaBridge 187:0387e8f68319 79 #define TMR_CMP_MIN 2
AnnaBridge 187:0387e8f68319 80 #define TMR_CMP_MAX 0xFFFFFFu
AnnaBridge 187:0387e8f68319 81
AnnaBridge 187:0387e8f68319 82 /* Synchronization issue with LXT/LIRC-clocked Timer
AnnaBridge 187:0387e8f68319 83 *
AnnaBridge 187:0387e8f68319 84 * PCLK : typical HCLK/2
AnnaBridge 187:0387e8f68319 85 * ECLK (engine clock) : LXT/LIRC for Timer used to implement lp_ticker
AnnaBridge 187:0387e8f68319 86 *
AnnaBridge 187:0387e8f68319 87 * When system clock is higher than Timer clock (LXT/LIRC), we need to add delay for ECLK
AnnaBridge 187:0387e8f68319 88 * domain to take effect:
AnnaBridge 187:0387e8f68319 89 * 1. Write : typical 1PCLK + 2ECLK
AnnaBridge 187:0387e8f68319 90 * Read-check doesn't work because it just checks PCLK domain and doesn't check into
AnnaBridge 187:0387e8f68319 91 * ECLK domain.
AnnaBridge 187:0387e8f68319 92 * 2. Clear interrupt flag : typical 2PCLK
AnnaBridge 187:0387e8f68319 93 * It is very rare that we would meet dummy interrupt and get stuck in ISR until
AnnaBridge 187:0387e8f68319 94 * 'clear interrupt flag' takes effect. The issue is ignorable because the pending
AnnaBridge 187:0387e8f68319 95 * time is very short (at most 1 dummy interrupt). We won't take special handling for it.
AnnaBridge 187:0387e8f68319 96 */
AnnaBridge 187:0387e8f68319 97
AnnaBridge 187:0387e8f68319 98 void lp_ticker_init(void)
AnnaBridge 187:0387e8f68319 99 {
AnnaBridge 187:0387e8f68319 100 if (ticker_inited) {
AnnaBridge 187:0387e8f68319 101 /* By HAL spec, ticker_init allows the ticker to keep counting and disables the
AnnaBridge 187:0387e8f68319 102 * ticker interrupt. */
AnnaBridge 187:0387e8f68319 103 lp_ticker_disable_interrupt();
AnnaBridge 187:0387e8f68319 104 return;
AnnaBridge 187:0387e8f68319 105 }
AnnaBridge 187:0387e8f68319 106 ticker_inited = 1;
AnnaBridge 187:0387e8f68319 107
AnnaBridge 187:0387e8f68319 108 /* Reset module
AnnaBridge 187:0387e8f68319 109 *
AnnaBridge 187:0387e8f68319 110 * NOTE: We must call secure version (from non-secure domain) because SYS/CLK regions are secure.
AnnaBridge 187:0387e8f68319 111 */
AnnaBridge 187:0387e8f68319 112 SYS_ResetModule_S(TIMER_MODINIT.rsetidx);
AnnaBridge 187:0387e8f68319 113
AnnaBridge 187:0387e8f68319 114 /* Select IP clock source
AnnaBridge 187:0387e8f68319 115 *
AnnaBridge 187:0387e8f68319 116 * NOTE: We must call secure version (from non-secure domain) because SYS/CLK regions are secure.
AnnaBridge 187:0387e8f68319 117 */
AnnaBridge 187:0387e8f68319 118 CLK_SetModuleClock_S(TIMER_MODINIT.clkidx, TIMER_MODINIT.clksrc, TIMER_MODINIT.clkdiv);
AnnaBridge 187:0387e8f68319 119
AnnaBridge 187:0387e8f68319 120 /* Enable IP clock
AnnaBridge 187:0387e8f68319 121 *
AnnaBridge 187:0387e8f68319 122 * NOTE: We must call secure version (from non-secure domain) because SYS/CLK regions are secure.
AnnaBridge 187:0387e8f68319 123 */
AnnaBridge 187:0387e8f68319 124 CLK_EnableModuleClock_S(TIMER_MODINIT.clkidx);
AnnaBridge 187:0387e8f68319 125
AnnaBridge 187:0387e8f68319 126 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 187:0387e8f68319 127
AnnaBridge 187:0387e8f68319 128 // Configure clock
AnnaBridge 187:0387e8f68319 129 uint32_t clk_timer = TIMER_GetModuleClock(timer_base);
AnnaBridge 187:0387e8f68319 130 uint32_t prescale_timer = clk_timer / NU_TMRCLK_PER_SEC - 1;
AnnaBridge 187:0387e8f68319 131 MBED_ASSERT((prescale_timer != (uint32_t) -1) && prescale_timer <= 127);
AnnaBridge 187:0387e8f68319 132 MBED_ASSERT((clk_timer % NU_TMRCLK_PER_SEC) == 0);
AnnaBridge 187:0387e8f68319 133 uint32_t cmp_timer = TMR_CMP_MAX;
AnnaBridge 187:0387e8f68319 134 MBED_ASSERT(cmp_timer >= TMR_CMP_MIN && cmp_timer <= TMR_CMP_MAX);
AnnaBridge 187:0387e8f68319 135 // Continuous mode
AnnaBridge 187:0387e8f68319 136 // NOTE: TIMER_CTL_CNTDATEN_Msk exists in NUC472, but not in M451/M480/M2351. In M451/M480/M2351, TIMER_CNT is updated continuously by default.
AnnaBridge 187:0387e8f68319 137 timer_base->CTL = TIMER_CONTINUOUS_MODE | prescale_timer/* | TIMER_CTL_CNTDATEN_Msk*/;
AnnaBridge 188:bcfe06ba3d64 138 nu_busy_wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
AnnaBridge 187:0387e8f68319 139
AnnaBridge 187:0387e8f68319 140 timer_base->CMP = cmp_timer;
AnnaBridge 188:bcfe06ba3d64 141 nu_busy_wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
AnnaBridge 187:0387e8f68319 142
AnnaBridge 187:0387e8f68319 143 // Set vector
AnnaBridge 187:0387e8f68319 144 NVIC_SetVector(TIMER_MODINIT.irq_n, (uint32_t) TIMER_MODINIT.var);
AnnaBridge 187:0387e8f68319 145
AnnaBridge 187:0387e8f68319 146 NVIC_DisableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 147
AnnaBridge 187:0387e8f68319 148 TIMER_EnableInt(timer_base);
AnnaBridge 188:bcfe06ba3d64 149 nu_busy_wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
AnnaBridge 187:0387e8f68319 150
AnnaBridge 187:0387e8f68319 151 TIMER_EnableWakeup(timer_base);
AnnaBridge 188:bcfe06ba3d64 152 nu_busy_wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
AnnaBridge 187:0387e8f68319 153
AnnaBridge 187:0387e8f68319 154 TIMER_Start(timer_base);
AnnaBridge 188:bcfe06ba3d64 155 nu_busy_wait_us((NU_US_PER_SEC / NU_TMRCLK_PER_SEC) * 3);
AnnaBridge 187:0387e8f68319 156
AnnaBridge 187:0387e8f68319 157 /* Wait for timer to start counting and raise active flag */
AnnaBridge 187:0387e8f68319 158 while(! (timer_base->CTL & TIMER_CTL_ACTSTS_Msk));
AnnaBridge 187:0387e8f68319 159 }
AnnaBridge 187:0387e8f68319 160
AnnaBridge 187:0387e8f68319 161 void lp_ticker_free(void)
AnnaBridge 187:0387e8f68319 162 {
AnnaBridge 187:0387e8f68319 163 /* Disable interrupt */
AnnaBridge 187:0387e8f68319 164 NVIC_DisableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 165
AnnaBridge 187:0387e8f68319 166 /* Disable IP clock
AnnaBridge 187:0387e8f68319 167 *
AnnaBridge 187:0387e8f68319 168 * NOTE: We must call secure version (from non-secure domain) because SYS/CLK regions are secure.
AnnaBridge 187:0387e8f68319 169 */
AnnaBridge 187:0387e8f68319 170 CLK_DisableModuleClock_S(TIMER_MODINIT.clkidx);
AnnaBridge 187:0387e8f68319 171
AnnaBridge 187:0387e8f68319 172 ticker_inited = 0;
AnnaBridge 187:0387e8f68319 173 }
AnnaBridge 187:0387e8f68319 174
AnnaBridge 187:0387e8f68319 175 timestamp_t lp_ticker_read()
AnnaBridge 187:0387e8f68319 176 {
AnnaBridge 187:0387e8f68319 177 if (! ticker_inited) {
AnnaBridge 187:0387e8f68319 178 lp_ticker_init();
AnnaBridge 187:0387e8f68319 179 }
AnnaBridge 187:0387e8f68319 180
AnnaBridge 187:0387e8f68319 181 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 187:0387e8f68319 182
AnnaBridge 187:0387e8f68319 183 return (TIMER_GetCounter(timer_base) / NU_TMRCLK_PER_TICK);
AnnaBridge 187:0387e8f68319 184 }
AnnaBridge 187:0387e8f68319 185
AnnaBridge 187:0387e8f68319 186 void lp_ticker_set_interrupt(timestamp_t timestamp)
AnnaBridge 187:0387e8f68319 187 {
AnnaBridge 188:bcfe06ba3d64 188 /* Clear any previously pending interrupts */
AnnaBridge 188:bcfe06ba3d64 189 lp_ticker_clear_interrupt();
AnnaBridge 188:bcfe06ba3d64 190 NVIC_ClearPendingIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 188:bcfe06ba3d64 191
AnnaBridge 187:0387e8f68319 192 /* In continuous mode, counter will be reset to zero with the following sequence:
AnnaBridge 187:0387e8f68319 193 * 1. Stop counting
AnnaBridge 187:0387e8f68319 194 * 2. Configure new CMP value
AnnaBridge 187:0387e8f68319 195 * 3. Restart counting
AnnaBridge 187:0387e8f68319 196 *
AnnaBridge 187:0387e8f68319 197 * This behavior is not what we want. To fix it, we could configure new CMP value
AnnaBridge 187:0387e8f68319 198 * without stopping counting first.
AnnaBridge 187:0387e8f68319 199 */
AnnaBridge 187:0387e8f68319 200 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 187:0387e8f68319 201
AnnaBridge 187:0387e8f68319 202 /* NOTE: Because H/W timer requests min compare value, our implementation would have alarm delay of
AnnaBridge 187:0387e8f68319 203 * (TMR_CMP_MIN - interval_clk) clocks when interval_clk is between [1, TMR_CMP_MIN). */
AnnaBridge 187:0387e8f68319 204 uint32_t cmp_timer = timestamp * NU_TMRCLK_PER_TICK;
AnnaBridge 187:0387e8f68319 205 cmp_timer = NU_CLAMP(cmp_timer, TMR_CMP_MIN, TMR_CMP_MAX);
AnnaBridge 187:0387e8f68319 206
AnnaBridge 187:0387e8f68319 207 /* NOTE: Rely on LPTICKER_DELAY_TICKS to be non-blocking. */
AnnaBridge 187:0387e8f68319 208 timer_base->CMP = cmp_timer;
AnnaBridge 187:0387e8f68319 209
AnnaBridge 187:0387e8f68319 210 /* We can call ticker_irq_handler now. */
AnnaBridge 187:0387e8f68319 211 NVIC_EnableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 212 }
AnnaBridge 187:0387e8f68319 213
AnnaBridge 187:0387e8f68319 214 void lp_ticker_disable_interrupt(void)
AnnaBridge 187:0387e8f68319 215 {
AnnaBridge 187:0387e8f68319 216 /* We cannot call ticker_irq_handler now. */
AnnaBridge 187:0387e8f68319 217 NVIC_DisableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 218 }
AnnaBridge 187:0387e8f68319 219
AnnaBridge 187:0387e8f68319 220 void lp_ticker_clear_interrupt(void)
AnnaBridge 187:0387e8f68319 221 {
AnnaBridge 187:0387e8f68319 222 /* To avoid sync issue, we clear TIF/TWKF simultaneously rather than call separate
AnnaBridge 187:0387e8f68319 223 * driver API:
AnnaBridge 187:0387e8f68319 224 *
AnnaBridge 187:0387e8f68319 225 * TIMER_ClearIntFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 187:0387e8f68319 226 * TIMER_ClearWakeupFlag((TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname));
AnnaBridge 187:0387e8f68319 227 */
AnnaBridge 187:0387e8f68319 228 TIMER_T *timer_base = (TIMER_T *) NU_MODBASE(TIMER_MODINIT.modname);
AnnaBridge 187:0387e8f68319 229 timer_base->INTSTS = TIMER_INTSTS_TIF_Msk | TIMER_INTSTS_TWKF_Msk;
AnnaBridge 187:0387e8f68319 230 }
AnnaBridge 187:0387e8f68319 231
AnnaBridge 187:0387e8f68319 232 void lp_ticker_fire_interrupt(void)
AnnaBridge 187:0387e8f68319 233 {
AnnaBridge 187:0387e8f68319 234 // NOTE: This event was in the past. Set the interrupt as pending, but don't process it here.
AnnaBridge 187:0387e8f68319 235 // This prevents a recursive loop under heavy load which can lead to a stack overflow.
AnnaBridge 187:0387e8f68319 236 NVIC_SetPendingIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 237
AnnaBridge 187:0387e8f68319 238 /* We can call ticker_irq_handler now. */
AnnaBridge 187:0387e8f68319 239 NVIC_EnableIRQ(TIMER_MODINIT.irq_n);
AnnaBridge 187:0387e8f68319 240 }
AnnaBridge 187:0387e8f68319 241
AnnaBridge 187:0387e8f68319 242 const ticker_info_t* lp_ticker_get_info()
AnnaBridge 187:0387e8f68319 243 {
AnnaBridge 187:0387e8f68319 244 static const ticker_info_t info = {
AnnaBridge 187:0387e8f68319 245 NU_TMRCLK_PER_SEC / NU_TMRCLK_PER_TICK,
AnnaBridge 187:0387e8f68319 246 NU_TMR_MAXCNT_BITSIZE
AnnaBridge 187:0387e8f68319 247 };
AnnaBridge 187:0387e8f68319 248 return &info;
AnnaBridge 187:0387e8f68319 249 }
AnnaBridge 187:0387e8f68319 250
AnnaBridge 187:0387e8f68319 251 #if defined (__ARM_FEATURE_CMSE) && (__ARM_FEATURE_CMSE == 3U)
AnnaBridge 187:0387e8f68319 252 static void tmr1_vec(void)
AnnaBridge 187:0387e8f68319 253 #else
AnnaBridge 187:0387e8f68319 254 static void tmr3_vec(void)
AnnaBridge 187:0387e8f68319 255 #endif
AnnaBridge 187:0387e8f68319 256 {
AnnaBridge 187:0387e8f68319 257 lp_ticker_clear_interrupt();
AnnaBridge 187:0387e8f68319 258
AnnaBridge 187:0387e8f68319 259 // NOTE: lp_ticker_set_interrupt() may get called in lp_ticker_irq_handler();
AnnaBridge 187:0387e8f68319 260 lp_ticker_irq_handler();
AnnaBridge 187:0387e8f68319 261 }
AnnaBridge 187:0387e8f68319 262
AnnaBridge 187:0387e8f68319 263 #endif