rt-thread/bsp/fm33lc026/libraries/FM33LC0xx_FL_Driver/Src/fm33lc0xx_fl_rng.c

/**
  *******************************************************************************************************
  * @file    fm33lc0xx_fl_rng.c
  * @author  FMSH Application Team
  * @brief   Src file of RNG FL Module
  *******************************************************************************************************
  * @attention
  *
  * Copyright (c) [2019] [Fudan Microelectronics]
  * THIS SOFTWARE is licensed under the Mulan PSL v1.
  * can use this software according to the terms and conditions of the Mulan PSL v1.
  * You may obtain a copy of Mulan PSL v1 at:
  * http://license.coscl.org.cn/MulanPSL
  * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR
  * PURPOSE.
  * See the Mulan PSL v1 for more details.
  *
  *******************************************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "fm33lc0xx_fl_rcc.h"
#include "fm33lc0xx_fl_rng.h"
#include "fm33_assert.h"
/** @addtogroup FM33LC0XX_FL_Driver
  * @{
  */

/** @addtogroup RNG
  * @{
  */

/* Private macros ------------------------------------------------------------*/
/** @addtogroup RNG_FL_Private_Macros
* @{
*/
#define         IS_FL_RNG_INSTANCE(INTANCE)                         ((INTANCE) == RNG)

#define         IS_FL_RNG_CLOCK_PRESCALER(__VALUE__)               (((__VALUE__) == FL_RCC_RNG_PSC_DIV1)||\
                                                                     ((__VALUE__) == FL_RCC_RNG_PSC_DIV2)||\
                                                                     ((__VALUE__) == FL_RCC_RNG_PSC_DIV4)||\
                                                                     ((__VALUE__) == FL_RCC_RNG_PSC_DIV8)||\
                                                                     ((__VALUE__) == FL_RCC_RNG_PSC_DIV16)||\
                                                                     ((__VALUE__) == FL_RCC_RNG_PSC_DIV32))
/**
  *@}
  */

/** @addtogroup RNG_FL_EF_Init
  * @{
  */

/**
  * @brief  复位RNG
  *
  * @param  RNGx 外设入口地址
  *
  * @retval 错误状态，可能值：
  *         -FL_PASS 外设寄存器值恢复复位值
  *         -FL_FAIL 未成功执行
  */
FL_ErrorStatus FL_RNG_DeInit(RNG_Type *RNGx)
{
    assert_param(IS_FL_RNG_INSTANCE(RNGx));
    /* 使能外设复位 */
    FL_RCC_EnablePeripheralReset();
    /* 复位外设寄存器 */
    FL_RCC_EnableResetAPB2Peripheral(FL_RCC_RSTAPB_RNG);
    FL_RCC_DisableResetAPB2Peripheral(FL_RCC_RSTAPB_RNG);
    /* 关闭外设总线始时钟和工作时钟 */
    FL_RCC_DisableGroup2BusClock(FL_RCC_GROUP2_BUSCLK_RNG);
    /* 锁定外设复位 */
    FL_RCC_DisablePeripheralReset();
    return FL_PASS;
}

/**
  * @brief  配置RNG
  *
  * @param  RNGx 外设入口地址
  * @param  initStruct 指向 @ref FL_RNG_InitTypeDef 结构体的指针
  *
  * @note   RNG使用RCHF默认的8M作为时钟输入，经2分频后4M提供给RNG
  *
  * @retval 错误状态，可能值：
  *         -FL_PASS 配置成功
  *         -FL_FAIL 配置过程发生错误
  */
FL_ErrorStatus FL_RNG_Init(RNG_Type *RNGx)
{
    assert_param(IS_FL_RNG_INSTANCE(RNGx));
    /* RNG 使用RCHF作为工作时钟因此必须确认RCHF使能*/
    if(FL_RCC_RCHF_IsEnabled() != FL_SET)
    {
        FL_RCC_RCHF_Enable();
    }
    FL_RCC_EnableGroup2BusClock(FL_RCC_GROUP2_BUSCLK_RNG);
    /* RNG 工作时钟预分频*/
    switch(FL_RCC_RCHF_GetFrequency())
    {
        case FL_RCC_RCHF_FREQUENCY_8MHZ:
            FL_RCC_SetRNGPrescaler(FL_RCC_RNG_PSC_DIV2);
            break;
        case FL_RCC_RCHF_FREQUENCY_16MHZ:
            FL_RCC_SetRNGPrescaler(FL_RCC_RNG_PSC_DIV4);
            break;
        case FL_RCC_RCHF_FREQUENCY_24MHZ:
            FL_RCC_SetRNGPrescaler(FL_RCC_RNG_PSC_DIV8);
            break;
        default:
            FL_RCC_SetRNGPrescaler(FL_RCC_RNG_PSC_DIV2);
            break;
    }
    /* RNG 工作时钟使能*/
    FL_RCC_EnableGroup2OperationClock(FL_RCC_GROUP2_OPCLK_RNG);
    return FL_PASS;
}

/**
  * @brief  获取一次随机数
  *
  * @note   如果返回值为0xFFFFFFFF 则说明随机数生成失败，请用户检查此函数的返回值，失败时重新生成
  *
  * @retval 生成的随机数，生成失败返回0xFFFFFFFF
  *
  */
uint32_t GetRandomNumber(void)
{
    uint32_t rn32;
    FL_RNG_ClearFlag_RandomFail(RNG);
    FL_RNG_Enable(RNGCTL);
    /* 由于LFSR循环移位周期是32cycle，为保证随机数质量，应用应保证两次读取RNGOUT之间的间隔大于32个TRNG_CLK周期 */
    FL_DelayUs(12);
    FL_RNG_Disable(RNGCTL);
    rn32 = FL_RNG_ReadData(RNG);
    if(FL_RNG_IsActiveFlag_RandomFail(RNG))
    {
        FL_RNG_ClearFlag_RandomFail(RNG);
        return 0xFFFFFFFF;
    }
    return rn32;
}

/**
  * @brief  获取CRC32
  *
  * @param  dataIn 待计算的数据
  *
  * @retval 计算得到的CRC32，计算失败返回0xFFFFFFFF
  *
  */
uint32_t GetCrc32(uint32_t dataIn)
{
    uint32_t i = 0;
    uint32_t crc32 = 0;
    FL_RNG_CRC_WriteData(RNG, dataIn);
    FL_RNG_ClearFlag_CRCComplete(RNG);
    FL_RNG_CRC_Enable(RNG);
    while(0 == FL_RNG_IsActiveFlag_CRCComplete(RNG))
    {
        i++;
        if(i > 600)
        { break; }
    }
    if(i >= 600)
    {
        FL_RNG_ClearFlag_CRCComplete(RNG);
        FL_RNG_Disable(RNGCTL);
        return 0xFFFFFFFF;
    }
    FL_RNG_ClearFlag_CRCComplete(RNG);
    crc32 = FL_RNG_ReadData(RNG);
    FL_RNG_Disable(RNGCTL);
    return crc32;
}

/**
  *@}
  */

/**
  *@}
  */

/**
  *@}
  */

/******************************************* END OF FILE *******************************************/