Johannes Stratmann / mbed-dev

added prescaler for 16 bit pwm in LPC1347 target

Fork of mbed-dev by mbed official

targets/hal/TARGET_Silicon_Labs/TARGET_EFM32/emlib/src/em_wdog.c@0:9b334a45a8ff, 2015-10-01 (annotated)

Committer:
bogdanm
Date:
Thu Oct 01 15:25:22 2015 +0300
Revision:
0:9b334a45a8ff
Child:
50:a417edff4437
Initial commit on mbed-dev



Replaces mbed-src (now inactive)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 0:9b334a45a8ff 1 /***************************************************************************//**
bogdanm 0:9b334a45a8ff 2 * @file em_wdog.c
bogdanm 0:9b334a45a8ff 3 * @brief Watchdog (WDOG) peripheral API
bogdanm 0:9b334a45a8ff 4 * devices.
bogdanm 0:9b334a45a8ff 5 * @version 3.20.12
bogdanm 0:9b334a45a8ff 6 *******************************************************************************
bogdanm 0:9b334a45a8ff 7 * @section License
bogdanm 0:9b334a45a8ff 8 * <b>(C) Copyright 2014 Silicon Labs, http://www.silabs.com</b>
bogdanm 0:9b334a45a8ff 9 *******************************************************************************
bogdanm 0:9b334a45a8ff 10 *
bogdanm 0:9b334a45a8ff 11 * Permission is granted to anyone to use this software for any purpose,
bogdanm 0:9b334a45a8ff 12 * including commercial applications, and to alter it and redistribute it
bogdanm 0:9b334a45a8ff 13 * freely, subject to the following restrictions:
bogdanm 0:9b334a45a8ff 14 *
bogdanm 0:9b334a45a8ff 15 * 1. The origin of this software must not be misrepresented; you must not
bogdanm 0:9b334a45a8ff 16 * claim that you wrote the original software.
bogdanm 0:9b334a45a8ff 17 * 2. Altered source versions must be plainly marked as such, and must not be
bogdanm 0:9b334a45a8ff 18 * misrepresented as being the original software.
bogdanm 0:9b334a45a8ff 19 * 3. This notice may not be removed or altered from any source distribution.
bogdanm 0:9b334a45a8ff 20 *
bogdanm 0:9b334a45a8ff 21 * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Labs has no
bogdanm 0:9b334a45a8ff 22 * obligation to support this Software. Silicon Labs is providing the
bogdanm 0:9b334a45a8ff 23 * Software "AS IS", with no express or implied warranties of any kind,
bogdanm 0:9b334a45a8ff 24 * including, but not limited to, any implied warranties of merchantability
bogdanm 0:9b334a45a8ff 25 * or fitness for any particular purpose or warranties against infringement
bogdanm 0:9b334a45a8ff 26 * of any proprietary rights of a third party.
bogdanm 0:9b334a45a8ff 27 *
bogdanm 0:9b334a45a8ff 28 * Silicon Labs will not be liable for any consequential, incidental, or
bogdanm 0:9b334a45a8ff 29 * special damages, or any other relief, or for any claim by any third party,
bogdanm 0:9b334a45a8ff 30 * arising from your use of this Software.
bogdanm 0:9b334a45a8ff 31 *
bogdanm 0:9b334a45a8ff 32 ******************************************************************************/
bogdanm 0:9b334a45a8ff 33
bogdanm 0:9b334a45a8ff 34
bogdanm 0:9b334a45a8ff 35 #include "em_wdog.h"
bogdanm 0:9b334a45a8ff 36 #if defined(WDOG_COUNT) && (WDOG_COUNT > 0)
bogdanm 0:9b334a45a8ff 37
bogdanm 0:9b334a45a8ff 38 #include "em_bitband.h"
bogdanm 0:9b334a45a8ff 39
bogdanm 0:9b334a45a8ff 40 /***************************************************************************//**
bogdanm 0:9b334a45a8ff 41 * @addtogroup EM_Library
bogdanm 0:9b334a45a8ff 42 * @{
bogdanm 0:9b334a45a8ff 43 ******************************************************************************/
bogdanm 0:9b334a45a8ff 44
bogdanm 0:9b334a45a8ff 45 /***************************************************************************//**
bogdanm 0:9b334a45a8ff 46 * @addtogroup WDOG
bogdanm 0:9b334a45a8ff 47 * @brief Watchdog (WDOG) Peripheral API
bogdanm 0:9b334a45a8ff 48 * @{
bogdanm 0:9b334a45a8ff 49 ******************************************************************************/
bogdanm 0:9b334a45a8ff 50
bogdanm 0:9b334a45a8ff 51 /*******************************************************************************
bogdanm 0:9b334a45a8ff 52 ************************** GLOBAL FUNCTIONS *******************************
bogdanm 0:9b334a45a8ff 53 ******************************************************************************/
bogdanm 0:9b334a45a8ff 54
bogdanm 0:9b334a45a8ff 55 /***************************************************************************//**
bogdanm 0:9b334a45a8ff 56 * @brief
bogdanm 0:9b334a45a8ff 57 * Enable/disable the watchdog timer.
bogdanm 0:9b334a45a8ff 58 *
bogdanm 0:9b334a45a8ff 59 * @note
bogdanm 0:9b334a45a8ff 60 * This function modifies the WDOG CTRL register which requires
bogdanm 0:9b334a45a8ff 61 * synchronization into the low frequency domain. If this register is modified
bogdanm 0:9b334a45a8ff 62 * before a previous update to the same register has completed, this function
bogdanm 0:9b334a45a8ff 63 * will stall until the previous synchronization has completed.
bogdanm 0:9b334a45a8ff 64 *
bogdanm 0:9b334a45a8ff 65 * @param[in] enable
bogdanm 0:9b334a45a8ff 66 * true to enable watchdog, false to disable. Watchdog cannot be disabled if
bogdanm 0:9b334a45a8ff 67 * watchdog has been locked.
bogdanm 0:9b334a45a8ff 68 ******************************************************************************/
bogdanm 0:9b334a45a8ff 69 void WDOG_Enable(bool enable)
bogdanm 0:9b334a45a8ff 70 {
bogdanm 0:9b334a45a8ff 71 if (!enable)
bogdanm 0:9b334a45a8ff 72 {
bogdanm 0:9b334a45a8ff 73 /* Wait for any pending previous write operation to have been completed in */
bogdanm 0:9b334a45a8ff 74 /* low frequency domain */
bogdanm 0:9b334a45a8ff 75 while (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL)
bogdanm 0:9b334a45a8ff 76 ;
bogdanm 0:9b334a45a8ff 77 }
bogdanm 0:9b334a45a8ff 78 BITBAND_Peripheral(&(WDOG->CTRL), _WDOG_CTRL_EN_SHIFT, (unsigned int)enable);
bogdanm 0:9b334a45a8ff 79 }
bogdanm 0:9b334a45a8ff 80
bogdanm 0:9b334a45a8ff 81
bogdanm 0:9b334a45a8ff 82 /***************************************************************************//**
bogdanm 0:9b334a45a8ff 83 * @brief
bogdanm 0:9b334a45a8ff 84 * Feed the watchdog.
bogdanm 0:9b334a45a8ff 85 *
bogdanm 0:9b334a45a8ff 86 * @details
bogdanm 0:9b334a45a8ff 87 * When the watchdog is activated, it must be fed (ie clearing the counter)
bogdanm 0:9b334a45a8ff 88 * before it reaches the defined timeout period. Otherwise, the watchdog
bogdanm 0:9b334a45a8ff 89 * will generate a reset.
bogdanm 0:9b334a45a8ff 90 ******************************************************************************/
bogdanm 0:9b334a45a8ff 91 void WDOG_Feed(void)
bogdanm 0:9b334a45a8ff 92 {
bogdanm 0:9b334a45a8ff 93 /* The watchdog should not be fed while it is disabled */
bogdanm 0:9b334a45a8ff 94 if ( !(WDOG->CTRL & WDOG_CTRL_EN) )
bogdanm 0:9b334a45a8ff 95 {
bogdanm 0:9b334a45a8ff 96 return;
bogdanm 0:9b334a45a8ff 97 }
bogdanm 0:9b334a45a8ff 98
bogdanm 0:9b334a45a8ff 99 /* If a previous clearing is being synchronized to LF domain, then there */
bogdanm 0:9b334a45a8ff 100 /* is no point in waiting for it to complete before clearing over again. */
bogdanm 0:9b334a45a8ff 101 /* This avoids stalling the core in the typical use case where some idle loop */
bogdanm 0:9b334a45a8ff 102 /* keeps clearing the watchdog. */
bogdanm 0:9b334a45a8ff 103 if (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CMD)
bogdanm 0:9b334a45a8ff 104 {
bogdanm 0:9b334a45a8ff 105 return;
bogdanm 0:9b334a45a8ff 106 }
bogdanm 0:9b334a45a8ff 107 /* Before writing to the WDOG_CMD register we also need to make sure that
bogdanm 0:9b334a45a8ff 108 * any previous write to WDOG_CTRL is complete. */
bogdanm 0:9b334a45a8ff 109 while ( WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL );
bogdanm 0:9b334a45a8ff 110
bogdanm 0:9b334a45a8ff 111 WDOG->CMD = WDOG_CMD_CLEAR;
bogdanm 0:9b334a45a8ff 112 }
bogdanm 0:9b334a45a8ff 113
bogdanm 0:9b334a45a8ff 114
bogdanm 0:9b334a45a8ff 115 /***************************************************************************//**
bogdanm 0:9b334a45a8ff 116 * @brief
bogdanm 0:9b334a45a8ff 117 * Initialize watchdog (assuming the watchdog configuration has not been
bogdanm 0:9b334a45a8ff 118 * locked).
bogdanm 0:9b334a45a8ff 119 *
bogdanm 0:9b334a45a8ff 120 * @note
bogdanm 0:9b334a45a8ff 121 * This function modifies the WDOG CTRL register which requires
bogdanm 0:9b334a45a8ff 122 * synchronization into the low frequency domain. If this register is modified
bogdanm 0:9b334a45a8ff 123 * before a previous update to the same register has completed, this function
bogdanm 0:9b334a45a8ff 124 * will stall until the previous synchronization has completed.
bogdanm 0:9b334a45a8ff 125 *
bogdanm 0:9b334a45a8ff 126 * @param[in] init
bogdanm 0:9b334a45a8ff 127 * Structure holding watchdog configuration. A default setting
bogdanm 0:9b334a45a8ff 128 * #WDOG_INIT_DEFAULT is available for init.
bogdanm 0:9b334a45a8ff 129 ******************************************************************************/
bogdanm 0:9b334a45a8ff 130 void WDOG_Init(const WDOG_Init_TypeDef *init)
bogdanm 0:9b334a45a8ff 131 {
bogdanm 0:9b334a45a8ff 132 uint32_t setting;
bogdanm 0:9b334a45a8ff 133
bogdanm 0:9b334a45a8ff 134 if (init->enable)
bogdanm 0:9b334a45a8ff 135 {
bogdanm 0:9b334a45a8ff 136 setting = WDOG_CTRL_EN;
bogdanm 0:9b334a45a8ff 137 }
bogdanm 0:9b334a45a8ff 138 else
bogdanm 0:9b334a45a8ff 139 {
bogdanm 0:9b334a45a8ff 140 setting = 0;
bogdanm 0:9b334a45a8ff 141 }
bogdanm 0:9b334a45a8ff 142
bogdanm 0:9b334a45a8ff 143 if (init->debugRun)
bogdanm 0:9b334a45a8ff 144 {
bogdanm 0:9b334a45a8ff 145 setting |= WDOG_CTRL_DEBUGRUN;
bogdanm 0:9b334a45a8ff 146 }
bogdanm 0:9b334a45a8ff 147
bogdanm 0:9b334a45a8ff 148 if (init->em2Run)
bogdanm 0:9b334a45a8ff 149 {
bogdanm 0:9b334a45a8ff 150 setting |= WDOG_CTRL_EM2RUN;
bogdanm 0:9b334a45a8ff 151 }
bogdanm 0:9b334a45a8ff 152
bogdanm 0:9b334a45a8ff 153 if (init->em3Run)
bogdanm 0:9b334a45a8ff 154 {
bogdanm 0:9b334a45a8ff 155 setting |= WDOG_CTRL_EM3RUN;
bogdanm 0:9b334a45a8ff 156 }
bogdanm 0:9b334a45a8ff 157
bogdanm 0:9b334a45a8ff 158 if (init->em4Block)
bogdanm 0:9b334a45a8ff 159 {
bogdanm 0:9b334a45a8ff 160 setting |= WDOG_CTRL_EM4BLOCK;
bogdanm 0:9b334a45a8ff 161 }
bogdanm 0:9b334a45a8ff 162
bogdanm 0:9b334a45a8ff 163 if (init->swoscBlock)
bogdanm 0:9b334a45a8ff 164 {
bogdanm 0:9b334a45a8ff 165 setting |= WDOG_CTRL_SWOSCBLOCK;
bogdanm 0:9b334a45a8ff 166 }
bogdanm 0:9b334a45a8ff 167
bogdanm 0:9b334a45a8ff 168 setting |= ((uint32_t)(init->clkSel) << _WDOG_CTRL_CLKSEL_SHIFT) |
bogdanm 0:9b334a45a8ff 169 ((uint32_t)(init->perSel) << _WDOG_CTRL_PERSEL_SHIFT);
bogdanm 0:9b334a45a8ff 170
bogdanm 0:9b334a45a8ff 171 /* Wait for any pending previous write operation to have been completed in */
bogdanm 0:9b334a45a8ff 172 /* low frequency domain */
bogdanm 0:9b334a45a8ff 173 while (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL)
bogdanm 0:9b334a45a8ff 174 ;
bogdanm 0:9b334a45a8ff 175
bogdanm 0:9b334a45a8ff 176 WDOG->CTRL = setting;
bogdanm 0:9b334a45a8ff 177
bogdanm 0:9b334a45a8ff 178 /* Optional register locking */
bogdanm 0:9b334a45a8ff 179 if (init->lock)
bogdanm 0:9b334a45a8ff 180 {
bogdanm 0:9b334a45a8ff 181 if (init->enable)
bogdanm 0:9b334a45a8ff 182 {
bogdanm 0:9b334a45a8ff 183 WDOG_Lock();
bogdanm 0:9b334a45a8ff 184 }
bogdanm 0:9b334a45a8ff 185 else
bogdanm 0:9b334a45a8ff 186 {
bogdanm 0:9b334a45a8ff 187 BITBAND_Peripheral(&(WDOG->CTRL), _WDOG_CTRL_LOCK_SHIFT, 1);
bogdanm 0:9b334a45a8ff 188 }
bogdanm 0:9b334a45a8ff 189 }
bogdanm 0:9b334a45a8ff 190 }
bogdanm 0:9b334a45a8ff 191
bogdanm 0:9b334a45a8ff 192
bogdanm 0:9b334a45a8ff 193 /***************************************************************************//**
bogdanm 0:9b334a45a8ff 194 * @brief
bogdanm 0:9b334a45a8ff 195 * Lock the watchdog configuration.
bogdanm 0:9b334a45a8ff 196 *
bogdanm 0:9b334a45a8ff 197 * @details
bogdanm 0:9b334a45a8ff 198 * This prevents errors from overwriting the watchdog configuration, possibly
bogdanm 0:9b334a45a8ff 199 * disabling it. Only a reset can unlock the watchdog config, once locked.
bogdanm 0:9b334a45a8ff 200 *
bogdanm 0:9b334a45a8ff 201 * If the LFRCO or LFXO clocks are used to clock the watchdog, one should
bogdanm 0:9b334a45a8ff 202 * consider using the option of inhibiting those clocks to be disabled,
bogdanm 0:9b334a45a8ff 203 * please see the WDOG_Enable() init structure.
bogdanm 0:9b334a45a8ff 204 *
bogdanm 0:9b334a45a8ff 205 * @note
bogdanm 0:9b334a45a8ff 206 * This function modifies the WDOG CTRL register which requires
bogdanm 0:9b334a45a8ff 207 * synchronization into the low frequency domain. If this register is modified
bogdanm 0:9b334a45a8ff 208 * before a previous update to the same register has completed, this function
bogdanm 0:9b334a45a8ff 209 * will stall until the previous synchronization has completed.
bogdanm 0:9b334a45a8ff 210 ******************************************************************************/
bogdanm 0:9b334a45a8ff 211 void WDOG_Lock(void)
bogdanm 0:9b334a45a8ff 212 {
bogdanm 0:9b334a45a8ff 213 /* Wait for any pending previous write operation to have been completed in */
bogdanm 0:9b334a45a8ff 214 /* low frequency domain */
bogdanm 0:9b334a45a8ff 215 while (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL)
bogdanm 0:9b334a45a8ff 216 ;
bogdanm 0:9b334a45a8ff 217
bogdanm 0:9b334a45a8ff 218 /* Disable writing to the control register */
bogdanm 0:9b334a45a8ff 219 BITBAND_Peripheral(&(WDOG->CTRL), _WDOG_CTRL_LOCK_SHIFT, 1);
bogdanm 0:9b334a45a8ff 220 }
bogdanm 0:9b334a45a8ff 221
bogdanm 0:9b334a45a8ff 222
bogdanm 0:9b334a45a8ff 223 /** @} (end addtogroup WDOG) */
bogdanm 0:9b334a45a8ff 224 /** @} (end addtogroup EM_Library) */
bogdanm 0:9b334a45a8ff 225 #endif /* defined(WDOG_COUNT) && (WDOG_COUNT > 0) */