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hal/lp_ticker_api.h@169:a7c7b631e539, 2018-06-22 (annotated)

Committer:
Anna Bridge
Date:
Fri Jun 22 15:38:59 2018 +0100
Revision:
169:a7c7b631e539
Parent:
160:5571c4ff569f
Child:
170:e95d10626187
mbed library. Release version 162

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 156:ff21514d8981 1
AnnaBridge 156:ff21514d8981 2 /** \addtogroup hal */
AnnaBridge 156:ff21514d8981 3 /** @{*/
AnnaBridge 156:ff21514d8981 4 /* mbed Microcontroller Library
AnnaBridge 156:ff21514d8981 5 * Copyright (c) 2015 ARM Limited
AnnaBridge 156:ff21514d8981 6 *
AnnaBridge 156:ff21514d8981 7 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 156:ff21514d8981 8 * you may not use this file except in compliance with the License.
AnnaBridge 156:ff21514d8981 9 * You may obtain a copy of the License at
AnnaBridge 156:ff21514d8981 10 *
AnnaBridge 156:ff21514d8981 11 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 156:ff21514d8981 12 *
AnnaBridge 156:ff21514d8981 13 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 156:ff21514d8981 14 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 156:ff21514d8981 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 156:ff21514d8981 16 * See the License for the specific language governing permissions and
AnnaBridge 156:ff21514d8981 17 * limitations under the License.
AnnaBridge 156:ff21514d8981 18 */
AnnaBridge 156:ff21514d8981 19 #ifndef MBED_LPTICKER_API_H
AnnaBridge 156:ff21514d8981 20 #define MBED_LPTICKER_API_H
AnnaBridge 156:ff21514d8981 21
AnnaBridge 156:ff21514d8981 22 #include "device.h"
AnnaBridge 156:ff21514d8981 23
Anna Bridge 169:a7c7b631e539 24 #if DEVICE_LPTICKER
AnnaBridge 156:ff21514d8981 25
AnnaBridge 156:ff21514d8981 26 #include "hal/ticker_api.h"
AnnaBridge 156:ff21514d8981 27
AnnaBridge 156:ff21514d8981 28 #ifdef __cplusplus
AnnaBridge 156:ff21514d8981 29 extern "C" {
AnnaBridge 156:ff21514d8981 30 #endif
AnnaBridge 156:ff21514d8981 31
AnnaBridge 156:ff21514d8981 32 /**
Anna Bridge 169:a7c7b631e539 33 * \defgroup hal_lp_ticker Low Power Ticker
Anna Bridge 169:a7c7b631e539 34 * Low level interface to the low power ticker of a target
Anna Bridge 169:a7c7b631e539 35 *
Anna Bridge 169:a7c7b631e539 36 * # Defined behavior
Anna Bridge 169:a7c7b631e539 37 * * Has a reported frequency between 4KHz and 64KHz - verified by ::lp_ticker_info_test
Anna Bridge 169:a7c7b631e539 38 * * Has a counter that is at least 12 bits wide - verified by ::lp_ticker_info_test
Anna Bridge 169:a7c7b631e539 39 * * Continues operating in deep sleep mode - verified by ::lp_ticker_deepsleep_test
Anna Bridge 169:a7c7b631e539 40 * * All behavior defined by the @ref hal_ticker_shared "ticker specification"
Anna Bridge 169:a7c7b631e539 41 *
Anna Bridge 169:a7c7b631e539 42 * # Undefined behavior
Anna Bridge 169:a7c7b631e539 43 * * See the @ref hal_ticker_shared "ticker specification"
Anna Bridge 169:a7c7b631e539 44 * * Calling any function other than lp_ticker_init after calling lp_ticker_free
Anna Bridge 169:a7c7b631e539 45 *
Anna Bridge 169:a7c7b631e539 46 * # Potential bugs
Anna Bridge 169:a7c7b631e539 47 * * Glitches due to ripple counter - Verified by ::lp_ticker_glitch_test
Anna Bridge 169:a7c7b631e539 48 *
Anna Bridge 169:a7c7b631e539 49 * @see hal_lp_ticker_tests
Anna Bridge 169:a7c7b631e539 50 *
AnnaBridge 156:ff21514d8981 51 * @{
AnnaBridge 156:ff21514d8981 52 */
AnnaBridge 156:ff21514d8981 53
Anna Bridge 169:a7c7b631e539 54 /**
Anna Bridge 169:a7c7b631e539 55 * \defgroup hal_lp_ticker_tests Low Power Ticker tests
Anna Bridge 169:a7c7b631e539 56 * Tests to validate the proper implementation of the low power ticker
Anna Bridge 169:a7c7b631e539 57 *
Anna Bridge 169:a7c7b631e539 58 * To run the low power ticker hal tests use the command:
Anna Bridge 169:a7c7b631e539 59 *
Anna Bridge 169:a7c7b631e539 60 * mbed test -t <toolchain> -m <target> -n tests-mbed_hal-common_ticker*,tests-mbed_hal-lp_ticker*
Anna Bridge 169:a7c7b631e539 61 *
Anna Bridge 169:a7c7b631e539 62 */
Anna Bridge 169:a7c7b631e539 63
Anna Bridge 160:5571c4ff569f 64 typedef void (*ticker_irq_handler_type)(const ticker_data_t *const);
Anna Bridge 160:5571c4ff569f 65
Anna Bridge 160:5571c4ff569f 66 /** Set low power ticker IRQ handler
Anna Bridge 160:5571c4ff569f 67 *
Anna Bridge 160:5571c4ff569f 68 * @param ticker_irq_handler IRQ handler to be connected
Anna Bridge 160:5571c4ff569f 69 *
Anna Bridge 160:5571c4ff569f 70 * @return previous ticker IRQ handler
Anna Bridge 160:5571c4ff569f 71 *
Anna Bridge 169:a7c7b631e539 72 * @note by default IRQ handler is set to ::ticker_irq_handler
Anna Bridge 160:5571c4ff569f 73 * @note this function is primarily for testing purposes and it's not required part of HAL implementation
Anna Bridge 160:5571c4ff569f 74 *
Anna Bridge 160:5571c4ff569f 75 */
Anna Bridge 160:5571c4ff569f 76 ticker_irq_handler_type set_lp_ticker_irq_handler(ticker_irq_handler_type ticker_irq_handler);
Anna Bridge 160:5571c4ff569f 77
AnnaBridge 156:ff21514d8981 78 /** Get low power ticker's data
AnnaBridge 156:ff21514d8981 79 *
AnnaBridge 156:ff21514d8981 80 * @return The low power ticker data
AnnaBridge 156:ff21514d8981 81 */
AnnaBridge 156:ff21514d8981 82 const ticker_data_t* get_lp_ticker_data(void);
AnnaBridge 156:ff21514d8981 83
AnnaBridge 156:ff21514d8981 84 /** The wrapper for ticker_irq_handler, to pass lp ticker's data
AnnaBridge 156:ff21514d8981 85 *
AnnaBridge 156:ff21514d8981 86 */
AnnaBridge 156:ff21514d8981 87 void lp_ticker_irq_handler(void);
AnnaBridge 156:ff21514d8981 88
AnnaBridge 156:ff21514d8981 89 /* HAL lp ticker */
AnnaBridge 156:ff21514d8981 90
AnnaBridge 156:ff21514d8981 91 /** Initialize the low power ticker
AnnaBridge 156:ff21514d8981 92 *
Anna Bridge 169:a7c7b631e539 93 * Initialize or re-initialize the ticker. This resets all the
Anna Bridge 169:a7c7b631e539 94 * clocking and prescaler registers, along with disabling
Anna Bridge 169:a7c7b631e539 95 * the compare interrupt.
Anna Bridge 169:a7c7b631e539 96 *
Anna Bridge 169:a7c7b631e539 97 * Pseudo Code:
Anna Bridge 169:a7c7b631e539 98 * @code
Anna Bridge 169:a7c7b631e539 99 * void lp_ticker_init()
Anna Bridge 169:a7c7b631e539 100 * {
Anna Bridge 169:a7c7b631e539 101 * // Enable clock gate so processor can read LPTMR registers
Anna Bridge 169:a7c7b631e539 102 * POWER_CTRL |= POWER_CTRL_LPTMR_Msk;
Anna Bridge 169:a7c7b631e539 103 *
Anna Bridge 169:a7c7b631e539 104 * // Disable the timer and ensure it is powered down
Anna Bridge 169:a7c7b631e539 105 * LPTMR_CTRL &= ~(LPTMR_CTRL_ENABLE_Msk | LPTMR_CTRL_COMPARE_ENABLE_Msk);
Anna Bridge 169:a7c7b631e539 106 *
Anna Bridge 169:a7c7b631e539 107 * // Configure divisors - no division necessary
Anna Bridge 169:a7c7b631e539 108 * LPTMR_PRESCALE = 0;
Anna Bridge 169:a7c7b631e539 109 * LPTMR_CTRL |= LPTMR_CTRL_ENABLE_Msk;
Anna Bridge 169:a7c7b631e539 110 *
Anna Bridge 169:a7c7b631e539 111 * // Install the interrupt handler
Anna Bridge 169:a7c7b631e539 112 * NVIC_SetVector(LPTMR_IRQn, (uint32_t)lp_ticker_irq_handler);
Anna Bridge 169:a7c7b631e539 113 * NVIC_EnableIRQ(LPTMR_IRQn);
Anna Bridge 169:a7c7b631e539 114 * }
Anna Bridge 169:a7c7b631e539 115 * @endcode
AnnaBridge 156:ff21514d8981 116 */
AnnaBridge 156:ff21514d8981 117 void lp_ticker_init(void);
AnnaBridge 156:ff21514d8981 118
Anna Bridge 169:a7c7b631e539 119 /** Deinitialize the lower power ticker
Anna Bridge 169:a7c7b631e539 120 *
Anna Bridge 169:a7c7b631e539 121 * Powerdown the lp ticker in preparation for sleep, powerdown, or reset.
Anna Bridge 169:a7c7b631e539 122 *
Anna Bridge 169:a7c7b631e539 123 * After calling this function no other ticker functions should be called except
Anna Bridge 169:a7c7b631e539 124 * lp_ticker_init(). Calling any function other than init after freeing is
Anna Bridge 169:a7c7b631e539 125 * undefined.
Anna Bridge 169:a7c7b631e539 126 *
Anna Bridge 169:a7c7b631e539 127 * @note This function stops the ticker from counting.
Anna Bridge 169:a7c7b631e539 128 */
Anna Bridge 169:a7c7b631e539 129 void lp_ticker_free(void);
Anna Bridge 169:a7c7b631e539 130
Anna Bridge 169:a7c7b631e539 131 /** Read the current tick
Anna Bridge 169:a7c7b631e539 132 *
Anna Bridge 169:a7c7b631e539 133 * If no rollover has occurred, the seconds passed since lp_ticker_init()
Anna Bridge 169:a7c7b631e539 134 * was called can be found by dividing the ticks returned by this function
Anna Bridge 169:a7c7b631e539 135 * by the frequency returned by ::lp_ticker_get_info.
AnnaBridge 156:ff21514d8981 136 *
Anna Bridge 169:a7c7b631e539 137 * @return The current timer's counter value in ticks
Anna Bridge 169:a7c7b631e539 138 *
Anna Bridge 169:a7c7b631e539 139 * Pseudo Code:
Anna Bridge 169:a7c7b631e539 140 * @code
Anna Bridge 169:a7c7b631e539 141 * uint32_t lp_ticker_read()
Anna Bridge 169:a7c7b631e539 142 * {
Anna Bridge 169:a7c7b631e539 143 * uint16_t count;
Anna Bridge 169:a7c7b631e539 144 * uint16_t last_count;
Anna Bridge 169:a7c7b631e539 145 *
Anna Bridge 169:a7c7b631e539 146 * // Loop until the same tick is read twice since this
Anna Bridge 169:a7c7b631e539 147 * // is ripple counter on a different clock domain.
Anna Bridge 169:a7c7b631e539 148 * count = LPTMR_COUNT;
Anna Bridge 169:a7c7b631e539 149 * do {
Anna Bridge 169:a7c7b631e539 150 * last_count = count;
Anna Bridge 169:a7c7b631e539 151 * count = LPTMR_COUNT;
Anna Bridge 169:a7c7b631e539 152 * } while (last_count != count);
Anna Bridge 169:a7c7b631e539 153 *
Anna Bridge 169:a7c7b631e539 154 * return count;
Anna Bridge 169:a7c7b631e539 155 * }
Anna Bridge 169:a7c7b631e539 156 * @endcode
AnnaBridge 156:ff21514d8981 157 */
AnnaBridge 156:ff21514d8981 158 uint32_t lp_ticker_read(void);
AnnaBridge 156:ff21514d8981 159
AnnaBridge 156:ff21514d8981 160 /** Set interrupt for specified timestamp
AnnaBridge 156:ff21514d8981 161 *
Anna Bridge 169:a7c7b631e539 162 * @param timestamp The time in ticks to be set
Anna Bridge 169:a7c7b631e539 163 *
Anna Bridge 169:a7c7b631e539 164 * @note no special handling needs to be done for times in the past
Anna Bridge 169:a7c7b631e539 165 * as the common timer code will detect this and call
Anna Bridge 169:a7c7b631e539 166 * lp_ticker_fire_interrupt() if this is the case
Anna Bridge 169:a7c7b631e539 167 *
Anna Bridge 169:a7c7b631e539 168 * @note calling this function with timestamp of more than the supported
Anna Bridge 169:a7c7b631e539 169 * number of bits returned by ::lp_ticker_get_info results in undefined
Anna Bridge 169:a7c7b631e539 170 * behavior.
Anna Bridge 169:a7c7b631e539 171 *
Anna Bridge 169:a7c7b631e539 172 * Pseudo Code:
Anna Bridge 169:a7c7b631e539 173 * @code
Anna Bridge 169:a7c7b631e539 174 * void lp_ticker_set_interrupt(timestamp_t timestamp)
Anna Bridge 169:a7c7b631e539 175 * {
Anna Bridge 169:a7c7b631e539 176 * LPTMR_COMPARE = timestamp;
Anna Bridge 169:a7c7b631e539 177 * LPTMR_CTRL |= LPTMR_CTRL_COMPARE_ENABLE_Msk;
Anna Bridge 169:a7c7b631e539 178 * }
Anna Bridge 169:a7c7b631e539 179 * @endcode
AnnaBridge 156:ff21514d8981 180 */
AnnaBridge 156:ff21514d8981 181 void lp_ticker_set_interrupt(timestamp_t timestamp);
AnnaBridge 156:ff21514d8981 182
AnnaBridge 156:ff21514d8981 183 /** Disable low power ticker interrupt
AnnaBridge 156:ff21514d8981 184 *
Anna Bridge 169:a7c7b631e539 185 * Pseudo Code:
Anna Bridge 169:a7c7b631e539 186 * @code
Anna Bridge 169:a7c7b631e539 187 * void lp_ticker_disable_interrupt(void)
Anna Bridge 169:a7c7b631e539 188 * {
Anna Bridge 169:a7c7b631e539 189 * // Disable the compare interrupt
Anna Bridge 169:a7c7b631e539 190 * LPTMR_CTRL &= ~LPTMR_CTRL_COMPARE_ENABLE_Msk;
Anna Bridge 169:a7c7b631e539 191 * }
Anna Bridge 169:a7c7b631e539 192 * @endcode
AnnaBridge 156:ff21514d8981 193 */
AnnaBridge 156:ff21514d8981 194 void lp_ticker_disable_interrupt(void);
AnnaBridge 156:ff21514d8981 195
AnnaBridge 156:ff21514d8981 196 /** Clear the low power ticker interrupt
AnnaBridge 156:ff21514d8981 197 *
Anna Bridge 169:a7c7b631e539 198 * Pseudo Code:
Anna Bridge 169:a7c7b631e539 199 * @code
Anna Bridge 169:a7c7b631e539 200 * void lp_ticker_clear_interrupt(void)
Anna Bridge 169:a7c7b631e539 201 * {
Anna Bridge 169:a7c7b631e539 202 * // Write to the ICR (interrupt clear register) of the LPTMR
Anna Bridge 169:a7c7b631e539 203 * LPTMR_ICR = LPTMR_ICR_COMPARE_Msk;
Anna Bridge 169:a7c7b631e539 204 * }
Anna Bridge 169:a7c7b631e539 205 * @endcode
AnnaBridge 156:ff21514d8981 206 */
AnnaBridge 156:ff21514d8981 207 void lp_ticker_clear_interrupt(void);
AnnaBridge 156:ff21514d8981 208
AnnaBridge 156:ff21514d8981 209 /** Set pending interrupt that should be fired right away.
AnnaBridge 156:ff21514d8981 210 *
Anna Bridge 169:a7c7b631e539 211 * Pseudo Code:
Anna Bridge 169:a7c7b631e539 212 * @code
Anna Bridge 169:a7c7b631e539 213 * void lp_ticker_fire_interrupt(void)
Anna Bridge 169:a7c7b631e539 214 * {
Anna Bridge 169:a7c7b631e539 215 * NVIC_SetPendingIRQ(LPTMR_IRQn);
Anna Bridge 169:a7c7b631e539 216 * }
Anna Bridge 169:a7c7b631e539 217 * @endcode
AnnaBridge 156:ff21514d8981 218 */
AnnaBridge 156:ff21514d8981 219 void lp_ticker_fire_interrupt(void);
AnnaBridge 156:ff21514d8981 220
Anna Bridge 160:5571c4ff569f 221 /** Get frequency and counter bits of this ticker.
Anna Bridge 160:5571c4ff569f 222 *
Anna Bridge 169:a7c7b631e539 223 * Pseudo Code:
Anna Bridge 169:a7c7b631e539 224 * @code
Anna Bridge 169:a7c7b631e539 225 * const ticker_info_t* lp_ticker_get_info()
Anna Bridge 169:a7c7b631e539 226 * {
Anna Bridge 169:a7c7b631e539 227 * static const ticker_info_t info = {
Anna Bridge 169:a7c7b631e539 228 * 32768, // 32KHz
Anna Bridge 169:a7c7b631e539 229 * 16 // 16 bit counter
Anna Bridge 169:a7c7b631e539 230 * };
Anna Bridge 169:a7c7b631e539 231 * return &info;
Anna Bridge 169:a7c7b631e539 232 * }
Anna Bridge 169:a7c7b631e539 233 * @endcode
Anna Bridge 160:5571c4ff569f 234 */
Anna Bridge 160:5571c4ff569f 235 const ticker_info_t* lp_ticker_get_info(void);
Anna Bridge 160:5571c4ff569f 236
AnnaBridge 156:ff21514d8981 237 /**@}*/
AnnaBridge 156:ff21514d8981 238
AnnaBridge 156:ff21514d8981 239 #ifdef __cplusplus
AnnaBridge 156:ff21514d8981 240 }
AnnaBridge 156:ff21514d8981 241 #endif
AnnaBridge 156:ff21514d8981 242
AnnaBridge 156:ff21514d8981 243 #endif
AnnaBridge 156:ff21514d8981 244
AnnaBridge 156:ff21514d8981 245 #endif
AnnaBridge 156:ff21514d8981 246
AnnaBridge 156:ff21514d8981 247 /** @}*/