rt-thread-official/bsp/efm32/board.c

246 lines
7.2 KiB
C

/******************************************************************//**
* @file board.c
* @brief USART driver of RT-Thread RTOS for EFM32
* COPYRIGHT (C) 2011, RT-Thread Development Team
* @author onelife
* @version 0.4 beta
**********************************************************************
* @section License
* The license and distribution terms for this file may be found in the file LICENSE in this
* distribution or at http://www.rt-thread.org/license/LICENSE
**********************************************************************
* @section Change Logs
* Date Author Notes
* 2010-12-21 onelife Initial creation for EFM32
*********************************************************************/
/******************************************************************//**
* @addtogroup efm32
* @{
*********************************************************************/
/* Includes -------------------------------------------------------------------*/
#include "board.h"
/* Private typedef -------------------------------------------------------------*/
/* Private define --------------------------------------------------------------*/
#define IS_NVIC_VECTTAB(VECTTAB) (((VECTTAB) == RAM_MEM_BASE) || \
((VECTTAB) == FLASH_MEM_BASE))
#define IS_NVIC_OFFSET(OFFSET) ((OFFSET) < 0x000FFFFF)
/******************************************************************//**
* @addtogroup SysTick_clock_source
* @{
*********************************************************************/
#define SysTick_CLKSource_HCLK_Div8 ((uint32_t)0xFFFFFFFB)
#define SysTick_CLKSource_HCLK ((uint32_t)0x00000004)
#define IS_SYSTICK_CLK_SOURCE(SOURCE) (((SOURCE) == SysTick_CLKSource_HCLK) || \
((SOURCE) == SysTick_CLKSource_HCLK_Div8))
/******************************************************************//**
* @}
*********************************************************************/
/* Private macro --------------------------------------------------------------*/
/* Private variables ------------------------------------------------------------*/
/* Private function prototypes ---------------------------------------------------*/
/* Private functions ------------------------------------------------------------*/
/******************************************************************//**
* @brief
* Set the allocation and offset of the vector table
*
* @details
*
* @note
*
* @param[in] NVIC_VectTab
* Indicate the vector table is allocated in RAM or ROM
*
* @param[in] Offset
* The vector table offset
*********************************************************************/
static void NVIC_SetVectorTable(rt_uint32_t NVIC_VectTab, rt_uint32_t Offset)
{
/* Check the parameters */
RT_ASSERT(IS_NVIC_VECTTAB(NVIC_VectTab));
RT_ASSERT(IS_NVIC_OFFSET(Offset));
SCB->VTOR = NVIC_VectTab | (Offset & (rt_uint32_t)0x1FFFFF80);
}
/******************************************************************//**
* @brief
* Configure the address of vector table
*
* @details
*
* @note
*
*********************************************************************/
static void NVIC_Configuration(void)
{
#ifdef VECT_TAB_RAM
/* Set the vector table allocated at 0x20000000 */
NVIC_SetVectorTable(RAM_MEM_BASE, 0x0);
#else /* VECT_TAB_FLASH */
/* Set the vector table allocated at 0x00000000 */
NVIC_SetVectorTable(FLASH_MEM_BASE, 0x0);
#endif
/* Set NVIC Preemption Priority Bits: 0 bit for pre-emption, 4 bits for subpriority */
NVIC_SetPriorityGrouping(0x7UL);
/* Set Base Priority Mask Register */
__set_BASEPRI(EFM32_BASE_PRI_DEFAULT);
}
/******************************************************************//**
* @brief
* Enable high frequency crystal oscillator (HFXO), and set HFCLK domain to use HFXO as
* source.
*
* @details
*
* @note
*
*********************************************************************/
static void switchToHFXO(void)
{
CMU_TypeDef *cmu = CMU;
/* Turning on HFXO to increase frequency accuracy. */
/* Waiting until oscillator is stable */
cmu->OSCENCMD = CMU_OSCENCMD_HFXOEN;
while (!(cmu->STATUS && CMU_STATUS_HFXORDY)) ;
/* Switching the CPU clock source to HFXO */
cmu->CMD = CMU_CMD_HFCLKSEL_HFXO;
/* Turning off the high frequency RC Oscillator (HFRCO) */
/* GENERATL WARNING! Make sure not to disable the current
* source of the HFCLK. */
cmu->OSCENCMD = CMU_OSCENCMD_HFRCODIS;
}
/******************************************************************//**
* @brief
* Configure the SysTick clock source
*
* @details
*
* @note
*
* @param[in] SysTick_CLKSource
* Specifies the SysTick clock source.
*
* @arg SysTick_CLKSource_HCLK_Div8
* AHB clock divided by 8 selected as SysTick clock source.
*
* @arg SysTick_CLKSource_HCLK
* AHB clock selected as SysTick clock source.
*********************************************************************/
static void SysTick_CLKSourceConfig(uint32_t SysTick_CLKSource)
{
/* Check the parameters */
RT_ASSERT(IS_SYSTICK_CLK_SOURCE(SysTick_CLKSource));
if (SysTick_CLKSource == SysTick_CLKSource_HCLK)
{
SysTick->CTRL |= SysTick_CLKSource_HCLK;
}
else
{
SysTick->CTRL &= SysTick_CLKSource_HCLK_Div8;
}
}
/******************************************************************//**
* @brief
* Configure the SysTick for OS tick.
*
* @details
*
* @note
*
*********************************************************************/
static void SysTick_Configuration(void)
{
rt_uint32_t core_clock;
rt_uint32_t cnts;
switchToHFXO();
core_clock = SystemCoreClockGet();
cnts = core_clock / RT_TICK_PER_SECOND;
SysTick_Config(cnts);
SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK);
}
/******************************************************************//**
* @brief
* Initialize the board.
*
* @details
*
* @note
*
*********************************************************************/
void rt_hw_board_init(void)
{
/* Chip errata */
CHIP_Init();
/* NVIC Configuration */
NVIC_Configuration();
/* Configure external oscillator */
SystemHFXOClockSet(EFM32_HFXO_FREQUENCY);
/* Configure the SysTick */
SysTick_Configuration();
}
/******************************************************************//**
* @brief
* Initialize the hardware drivers.
*
* @details
*
* @note
*
*********************************************************************/
void rt_hw_driver_init(void)
{
CMU_ClockEnable(cmuClock_HFPER, true);
/* Enable GPIO */
CMU_ClockEnable(cmuClock_GPIO, true);
/* Enabling clock to the interface of the low energy modules */
CMU_ClockEnable(cmuClock_CORELE, true);
/* Initialize DMA */
rt_hw_dma_init();
/* Initialize USART */
rt_hw_usart_init();
/* Initialize Timer */
rt_hw_timer_init();
/* Initialize ADC */
rt_hw_adc_init();
/* Initialize ACMP */
rt_hw_acmp_init();
/* Initialize IIC */
rt_hw_iic_init();
rt_console_set_device(CONSOLE_DEVICE);
}
/******************************************************************//**
* @}
*********************************************************************/