/***************************************************************************//** | |
* @file system_efm32wg.c | |
* @brief CMSIS Cortex-M4 System Layer for EFM32WG devices. | |
* @version 5.1.2 | |
****************************************************************************** | |
* @section License | |
* <b>Copyright 2017 Silicon Laboratories, Inc. http://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) | |
#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 EFM32_nFXO_FREQ */ | |
/* values according to board design. By defining the EFM32_nFXO_FREQ to 0, */ | |
/* one indicates that the oscillator is not present, in order to save some */ | |
/* SW footprint. */ | |
#ifndef EFM32_HFXO_FREQ | |
#define EFM32_HFXO_FREQ (48000000UL) | |
#endif | |
#define EFM32_HFRCO_MAX_FREQ (28000000UL) | |
/* Do not define variable if HF crystal oscillator not present */ | |
#if (EFM32_HFXO_FREQ > 0) | |
/** @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 | |
#define EFM32_LFXO_FREQ (EFM32_LFRCO_FREQ) | |
#endif | |
/* Do not define variable if LF crystal oscillator not present */ | |
#if (EFM32_LFXO_FREQ > 0) | |
/** @cond DO_NOT_INCLUDE_WITH_DOXYGEN */ | |
/** System LFXO clock. */ | |
static uint32_t SystemLFXOClock = EFM32_LFXO_FREQ; | |
/** @endcond (DO_NOT_INCLUDE_WITH_DOXYGEN) */ | |
#endif | |
/* Inline function to get the chip's Production Revision. */ | |
__STATIC_INLINE uint8_t GetProdRev(void) | |
{ | |
return ((DEVINFO->PART & _DEVINFO_PART_PROD_REV_MASK) | |
>> _DEVINFO_PART_PROD_REV_SHIFT); | |
} | |
/******************************************************************************* | |
************************** GLOBAL VARIABLES ******************************* | |
******************************************************************************/ | |
/** | |
* @brief | |
* System System Clock Frequency (Core Clock). | |
* | |
* @details | |
* Required CMSIS global variable that must be kept up-to-date. | |
*/ | |
uint32_t SystemCoreClock; | |
/******************************************************************************* | |
************************** GLOBAL FUNCTIONS ******************************* | |
******************************************************************************/ | |
/***************************************************************************//** | |
* @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; | |
ret = SystemHFClockGet(); | |
ret >>= (CMU->HFCORECLKDIV & _CMU_HFCORECLKDIV_HFCORECLKDIV_MASK) >> | |
_CMU_HFCORECLKDIV_HFCORECLKDIV_SHIFT; | |
/* Keep CMSIS variable up-to-date just in case */ | |
SystemCoreClock = ret; | |
return ret; | |
} | |
/***************************************************************************//** | |
* @brief | |
* Get the maximum core clock frequency. | |
* | |
* @note | |
* This is an EFR32 proprietary function, not part of the CMSIS definition. | |
* | |
* @return | |
* The maximum core clock frequency in Hz. | |
******************************************************************************/ | |
uint32_t SystemMaxCoreClockGet(void) | |
{ | |
return (EFM32_HFRCO_MAX_FREQ > EFM32_HFXO_FREQ ? \ | |
EFM32_HFRCO_MAX_FREQ : EFM32_HFXO_FREQ); | |
} | |
/***************************************************************************//** | |
* @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->STATUS & (CMU_STATUS_HFRCOSEL | CMU_STATUS_HFXOSEL | | |
CMU_STATUS_LFRCOSEL | CMU_STATUS_LFXOSEL)) | |
{ | |
case CMU_STATUS_LFXOSEL: | |
#if (EFM32_LFXO_FREQ > 0) | |
ret = SystemLFXOClock; | |
#else | |
/* We should not get here, since core should not be clocked. May */ | |
/* be caused by a misconfiguration though. */ | |
ret = 0; | |
#endif | |
break; | |
case CMU_STATUS_LFRCOSEL: | |
ret = EFM32_LFRCO_FREQ; | |
break; | |
case CMU_STATUS_HFXOSEL: | |
#if (EFM32_HFXO_FREQ > 0) | |
ret = SystemHFXOClock; | |
#else | |
/* We should not get here, since core should not be clocked. May */ | |
/* be caused by a misconfiguration though. */ | |
ret = 0; | |
#endif | |
break; | |
default: /* CMU_STATUS_HFRCOSEL */ | |
switch (CMU->HFRCOCTRL & _CMU_HFRCOCTRL_BAND_MASK) | |
{ | |
case CMU_HFRCOCTRL_BAND_28MHZ: | |
ret = 28000000; | |
break; | |
case CMU_HFRCOCTRL_BAND_21MHZ: | |
ret = 21000000; | |
break; | |
case CMU_HFRCOCTRL_BAND_14MHZ: | |
ret = 14000000; | |
break; | |
case CMU_HFRCOCTRL_BAND_11MHZ: | |
ret = 11000000; | |
break; | |
case CMU_HFRCOCTRL_BAND_7MHZ: | |
if ( GetProdRev() >= 19 ) | |
ret = 6600000; | |
else | |
ret = 7000000; | |
break; | |
case CMU_HFRCOCTRL_BAND_1MHZ: | |
if ( GetProdRev() >= 19 ) | |
ret = 1200000; | |
else | |
ret = 1000000; | |
break; | |
default: | |
ret = 0; | |
break; | |
} | |
break; | |
} | |
return ret / (1U + ((CMU->CTRL & _CMU_CTRL_HFCLKDIV_MASK) | |
>> _CMU_CTRL_HFCLKDIV_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 > 0) | |
return SystemHFXOClock; | |
#else | |
return 0; | |
#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 > 0) | |
SystemHFXOClock = freq; | |
/* Update core clock frequency if HFXO is used to clock core */ | |
if (CMU->STATUS & CMU_STATUS_HFXOSEL) | |
{ | |
/* The function will update the global variable */ | |
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 (__FPU_PRESENT == 1) && (__FPU_USED == 1) | |
/* Set floating point coprosessor access mode. */ | |
SCB->CPACR |= ((3UL << 10*2) | /* set CP10 Full Access */ | |
(3UL << 11*2) ); /* set CP11 Full Access */ | |
#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 > 0) | |
return SystemLFXOClock; | |
#else | |
return 0; | |
#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 > 0) | |
SystemLFXOClock = freq; | |
/* Update core clock frequency if LFXO is used to clock core */ | |
if (CMU->STATUS & CMU_STATUS_LFXOSEL) | |
{ | |
/* The function will update the global variable */ | |
SystemCoreClockGet(); | |
} | |
#else | |
(void)freq; /* Unused parameter */ | |
#endif | |
} |