| /***************************************************************************//** |
| * @file system_efm32pg12b.c |
| * @brief CMSIS Cortex-M3/M4 System Layer for EFM32 devices. |
| * @version 5.6.0 |
| ****************************************************************************** |
| * # License |
| * <b>Copyright 2018 Silicon Laboratories, Inc. www.silabs.com</b> |
| ****************************************************************************** |
| * |
| * Permission is granted to anyone to use this software for any purpose, |
| * including commercial applications, and to alter it and redistribute it |
| * freely, subject to the following restrictions: |
| * |
| * 1. The origin of this software must not be misrepresented; you must not |
| * claim that you wrote the original software.@n |
| * 2. Altered source versions must be plainly marked as such, and must not be |
| * misrepresented as being the original software.@n |
| * 3. This notice may not be removed or altered from any source distribution. |
| * |
| * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Laboratories, Inc. |
| * has no obligation to support this Software. Silicon Laboratories, Inc. is |
| * providing the Software "AS IS", with no express or implied warranties of any |
| * kind, including, but not limited to, any implied warranties of |
| * merchantability or fitness for any particular purpose or warranties against |
| * infringement of any proprietary rights of a third party. |
| * |
| * Silicon Laboratories, Inc. will not be liable for any consequential, |
| * incidental, or special damages, or any other relief, or for any claim by |
| * any third party, arising from your use of this Software. |
| * |
| *****************************************************************************/ |
| |
| #include <stdint.h> |
| #include "em_device.h" |
| |
| /******************************************************************************* |
| ****************************** DEFINES ************************************ |
| ******************************************************************************/ |
| |
| /** LFRCO frequency, tuned to below frequency during manufacturing. */ |
| #define EFM32_LFRCO_FREQ (32768UL) |
| /** ULFRCO frequency */ |
| #define EFM32_ULFRCO_FREQ (1000UL) |
| |
| /******************************************************************************* |
| ************************** LOCAL VARIABLES ******************************** |
| ******************************************************************************/ |
| |
| /* System oscillator frequencies. These frequencies are normally constant */ |
| /* for a target, but they are made configurable in order to allow run-time */ |
| /* handling of different boards. The crystal oscillator clocks can be set */ |
| /* compile time to a non-default value by defining respective EFM_nFXO_FREQ */ |
| /* values according to board design. By defining the EFM_nFXO_FREQ to 0, */ |
| /* one indicates that the oscillator is not present, in order to save some */ |
| /* SW footprint. */ |
| |
| #ifndef EFM32_HFRCO_MAX_FREQ |
| /** Maximum HFRCO frequency */ |
| #define EFM32_HFRCO_MAX_FREQ (38000000UL) |
| #endif |
| |
| #ifndef EFM32_HFXO_FREQ |
| /** HFXO frequency */ |
| #define EFM32_HFXO_FREQ (40000000UL) |
| #endif |
| |
| #ifndef EFM32_HFRCO_STARTUP_FREQ |
| /** HFRCO startup frequency */ |
| #define EFM32_HFRCO_STARTUP_FREQ (19000000UL) |
| #endif |
| |
| /* Do not define variable if HF crystal oscillator not present */ |
| #if (EFM32_HFXO_FREQ > 0U) |
| /** @cond DO_NOT_INCLUDE_WITH_DOXYGEN */ |
| /** System HFXO clock. */ |
| static uint32_t SystemHFXOClock = EFM32_HFXO_FREQ; |
| /** @endcond (DO_NOT_INCLUDE_WITH_DOXYGEN) */ |
| #endif |
| |
| #ifndef EFM32_LFXO_FREQ |
| /** LFXO frequency */ |
| #define EFM32_LFXO_FREQ (EFM32_LFRCO_FREQ) |
| #endif |
| /* Do not define variable if LF crystal oscillator not present */ |
| #if (EFM32_LFXO_FREQ > 0U) |
| /** @cond DO_NOT_INCLUDE_WITH_DOXYGEN */ |
| /** System LFXO clock. */ |
| static uint32_t SystemLFXOClock = EFM32_LFXO_FREQ; |
| /** @endcond (DO_NOT_INCLUDE_WITH_DOXYGEN) */ |
| #endif |
| |
| /******************************************************************************* |
| ************************** GLOBAL VARIABLES ******************************* |
| ******************************************************************************/ |
| |
| /** |
| * @brief |
| * System System Clock Frequency (Core Clock). |
| * |
| * @details |
| * Required CMSIS global variable that must be kept up-to-date. |
| */ |
| uint32_t SystemCoreClock = EFM32_HFRCO_STARTUP_FREQ; |
| |
| /** |
| * @brief |
| * System HFRCO frequency |
| * |
| * @note |
| * This is an EFM32 proprietary variable, not part of the CMSIS definition. |
| * |
| * @details |
| * Frequency of the system HFRCO oscillator |
| */ |
| uint32_t SystemHfrcoFreq = EFM32_HFRCO_STARTUP_FREQ; |
| |
| /******************************************************************************* |
| ************************** GLOBAL FUNCTIONS ******************************* |
| ******************************************************************************/ |
| |
| #if defined(__VTOR_PRESENT) && (__VTOR_PRESENT == 1U) |
| #if defined(__ICCARM__) /* IAR requires the __vector_table symbol */ |
| #define __Vectors __vector_table |
| #endif |
| extern uint32_t __Vectors; |
| #endif |
| |
| /***************************************************************************//** |
| * @brief |
| * Get the current core clock frequency. |
| * |
| * @details |
| * Calculate and get the current core clock frequency based on the current |
| * configuration. Assuming that the SystemCoreClock global variable is |
| * maintained, the core clock frequency is stored in that variable as well. |
| * This function will however calculate the core clock based on actual HW |
| * configuration. It will also update the SystemCoreClock global variable. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @return |
| * The current core clock frequency in Hz. |
| ******************************************************************************/ |
| uint32_t SystemCoreClockGet(void) |
| { |
| uint32_t ret; |
| uint32_t presc; |
| |
| ret = SystemHFClockGet(); |
| presc = (CMU->HFCOREPRESC & _CMU_HFCOREPRESC_PRESC_MASK) |
| >> _CMU_HFCOREPRESC_PRESC_SHIFT; |
| ret /= presc + 1U; |
| |
| /* Keep CMSIS system clock variable up-to-date */ |
| SystemCoreClock = ret; |
| |
| return ret; |
| } |
| |
| /***************************************************************************//** |
| * @brief |
| * Get the maximum core clock frequency. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @return |
| * The maximum core clock frequency in Hz. |
| ******************************************************************************/ |
| uint32_t SystemMaxCoreClockGet(void) |
| { |
| #if (EFM32_HFRCO_MAX_FREQ > EFM32_HFXO_FREQ) |
| return EFM32_HFRCO_MAX_FREQ; |
| #else |
| return EFM32_HFXO_FREQ; |
| #endif |
| } |
| |
| /***************************************************************************//** |
| * @brief |
| * Get the current HFCLK frequency. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @return |
| * The current HFCLK frequency in Hz. |
| ******************************************************************************/ |
| uint32_t SystemHFClockGet(void) |
| { |
| uint32_t ret; |
| |
| switch (CMU->HFCLKSTATUS & _CMU_HFCLKSTATUS_SELECTED_MASK) { |
| case CMU_HFCLKSTATUS_SELECTED_LFXO: |
| #if (EFM32_LFXO_FREQ > 0U) |
| ret = SystemLFXOClock; |
| #else |
| /* We should not get here, since core should not be clocked. May */ |
| /* be caused by a misconfiguration though. */ |
| ret = 0U; |
| #endif |
| break; |
| |
| case CMU_HFCLKSTATUS_SELECTED_LFRCO: |
| ret = EFM32_LFRCO_FREQ; |
| break; |
| |
| case CMU_HFCLKSTATUS_SELECTED_HFXO: |
| #if (EFM32_HFXO_FREQ > 0U) |
| ret = SystemHFXOClock; |
| #else |
| /* We should not get here, since core should not be clocked. May */ |
| /* be caused by a misconfiguration though. */ |
| ret = 0U; |
| #endif |
| break; |
| |
| default: /* CMU_HFCLKSTATUS_SELECTED_HFRCO */ |
| ret = SystemHfrcoFreq; |
| break; |
| } |
| |
| return ret / (1U + ((CMU->HFPRESC & _CMU_HFPRESC_PRESC_MASK) |
| >> _CMU_HFPRESC_PRESC_SHIFT)); |
| } |
| |
| /**************************************************************************//** |
| * @brief |
| * Get high frequency crystal oscillator clock frequency for target system. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @return |
| * HFXO frequency in Hz. |
| *****************************************************************************/ |
| uint32_t SystemHFXOClockGet(void) |
| { |
| /* External crystal oscillator present? */ |
| #if (EFM32_HFXO_FREQ > 0U) |
| return SystemHFXOClock; |
| #else |
| return 0U; |
| #endif |
| } |
| |
| /**************************************************************************//** |
| * @brief |
| * Set high frequency crystal oscillator clock frequency for target system. |
| * |
| * @note |
| * This function is mainly provided for being able to handle target systems |
| * with different HF crystal oscillator frequencies run-time. If used, it |
| * should probably only be used once during system startup. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @param[in] freq |
| * HFXO frequency in Hz used for target. |
| *****************************************************************************/ |
| void SystemHFXOClockSet(uint32_t freq) |
| { |
| /* External crystal oscillator present? */ |
| #if (EFM32_HFXO_FREQ > 0U) |
| SystemHFXOClock = freq; |
| |
| /* Update core clock frequency if HFXO is used to clock core */ |
| if ((CMU->HFCLKSTATUS & _CMU_HFCLKSTATUS_SELECTED_MASK) |
| == CMU_HFCLKSTATUS_SELECTED_HFXO) { |
| /* The function will update the global variable */ |
| (void)SystemCoreClockGet(); |
| } |
| #else |
| (void)freq; /* Unused parameter */ |
| #endif |
| } |
| |
| /**************************************************************************//** |
| * @brief |
| * Initialize the system. |
| * |
| * @details |
| * Do required generic HW system init. |
| * |
| * @note |
| * This function is invoked during system init, before the main() routine |
| * and any data has been initialized. For this reason, it cannot do any |
| * initialization of variables etc. |
| *****************************************************************************/ |
| void SystemInit(void) |
| { |
| #if defined(__VTOR_PRESENT) && (__VTOR_PRESENT == 1U) |
| SCB->VTOR = (uint32_t)&__Vectors; |
| #endif |
| |
| #if (__FPU_PRESENT == 1U) && (__FPU_USED == 1U) |
| /* Set floating point coprosessor access mode. */ |
| SCB->CPACR |= ((3UL << 10 * 2) /* set CP10 Full Access */ |
| | (3UL << 11 * 2)); /* set CP11 Full Access */ |
| #endif |
| |
| #if defined(UNALIGNED_SUPPORT_DISABLE) |
| SCB->CCR |= SCB_CCR_UNALIGN_TRP_Msk; |
| #endif |
| } |
| |
| /**************************************************************************//** |
| * @brief |
| * Get low frequency RC oscillator clock frequency for target system. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @return |
| * LFRCO frequency in Hz. |
| *****************************************************************************/ |
| uint32_t SystemLFRCOClockGet(void) |
| { |
| /* Currently we assume that this frequency is properly tuned during */ |
| /* manufacturing and is not changed after reset. If future requirements */ |
| /* for re-tuning by user, we can add support for that. */ |
| return EFM32_LFRCO_FREQ; |
| } |
| |
| /**************************************************************************//** |
| * @brief |
| * Get ultra low frequency RC oscillator clock frequency for target system. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @return |
| * ULFRCO frequency in Hz. |
| *****************************************************************************/ |
| uint32_t SystemULFRCOClockGet(void) |
| { |
| /* The ULFRCO frequency is not tuned, and can be very inaccurate */ |
| return EFM32_ULFRCO_FREQ; |
| } |
| |
| /**************************************************************************//** |
| * @brief |
| * Get low frequency crystal oscillator clock frequency for target system. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @return |
| * LFXO frequency in Hz. |
| *****************************************************************************/ |
| uint32_t SystemLFXOClockGet(void) |
| { |
| /* External crystal oscillator present? */ |
| #if (EFM32_LFXO_FREQ > 0U) |
| return SystemLFXOClock; |
| #else |
| return 0U; |
| #endif |
| } |
| |
| /**************************************************************************//** |
| * @brief |
| * Set low frequency crystal oscillator clock frequency for target system. |
| * |
| * @note |
| * This function is mainly provided for being able to handle target systems |
| * with different HF crystal oscillator frequencies run-time. If used, it |
| * should probably only be used once during system startup. |
| * |
| * @note |
| * This is an EFM32 proprietary function, not part of the CMSIS definition. |
| * |
| * @param[in] freq |
| * LFXO frequency in Hz used for target. |
| *****************************************************************************/ |
| void SystemLFXOClockSet(uint32_t freq) |
| { |
| /* External crystal oscillator present? */ |
| #if (EFM32_LFXO_FREQ > 0U) |
| SystemLFXOClock = freq; |
| |
| /* Update core clock frequency if LFXO is used to clock core */ |
| if ((CMU->HFCLKSTATUS & _CMU_HFCLKSTATUS_SELECTED_MASK) |
| == CMU_HFCLKSTATUS_SELECTED_LFXO) { |
| /* The function will update the global variable */ |
| (void)SystemCoreClockGet(); |
| } |
| #else |
| (void)freq; /* Unused parameter */ |
| #endif |
| } |