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Diffstat (limited to 'thirdparty/STM32_USB-FS-Device_Lib_V4.0.0/Projects/Virtual_COM_Port/src/system_stm32f30x.c')
| -rw-r--r-- | thirdparty/STM32_USB-FS-Device_Lib_V4.0.0/Projects/Virtual_COM_Port/src/system_stm32f30x.c | 382 |
1 files changed, 382 insertions, 0 deletions
diff --git a/thirdparty/STM32_USB-FS-Device_Lib_V4.0.0/Projects/Virtual_COM_Port/src/system_stm32f30x.c b/thirdparty/STM32_USB-FS-Device_Lib_V4.0.0/Projects/Virtual_COM_Port/src/system_stm32f30x.c new file mode 100644 index 0000000..31faf5c --- /dev/null +++ b/thirdparty/STM32_USB-FS-Device_Lib_V4.0.0/Projects/Virtual_COM_Port/src/system_stm32f30x.c @@ -0,0 +1,382 @@ +/** + ****************************************************************************** + * @file system_stm32f30x.c + * @author MCD Application Team + * @version V4.0.0 + * @date 21-January-2013 + * @brief CMSIS Cortex-M4 Device Peripheral Access Layer System Source File. + * This file contains the system clock configuration for STM32F30x devices, + * and is generated by the clock configuration tool + * stm32f30x_Clock_Configuration_V1.0.0.xls + * + * 1. This file provides two functions and one global variable to be called from + * user application: + * - SystemInit(): Setups the system clock (System clock source, PLL Multiplier + * and Divider factors, AHB/APBx prescalers and Flash settings), + * depending on the configuration made in the clock xls tool. + * This function is called at startup just after reset and + * before branch to main program. This call is made inside + * the "startup_stm32f30x.s" file. + * + * - SystemCoreClock variable: Contains the core clock (HCLK), it can be used + * by the user application to setup the SysTick + * timer or configure other parameters. + * + * - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must + * be called whenever the core clock is changed + * during program execution. + * + * 2. After each device reset the HSI (8 MHz) is used as system clock source. + * Then SystemInit() function is called, in "startup_stm32f30x.s" file, to + * configure the system clock before to branch to main program. + * + * 3. If the system clock source selected by user fails to startup, the SystemInit() + * function will do nothing and HSI still used as system clock source. User can + * add some code to deal with this issue inside the SetSysClock() function. + * + * 4. The default value of HSE crystal is set to 8MHz, refer to "HSE_VALUE" define + * in "stm32f30x.h" file. When HSE is used as system clock source, directly or + * through PLL, and you are using different crystal you have to adapt the HSE + * value to your own configuration. + * + * 5. This file configures the system clock as follows: + *============================================================================= + * Supported STM32F30x device + *----------------------------------------------------------------------------- + * System Clock source | PLL (HSE) + *----------------------------------------------------------------------------- + * SYSCLK(Hz) | 72000000 + *----------------------------------------------------------------------------- + * HCLK(Hz) | 72000000 + *----------------------------------------------------------------------------- + * AHB Prescaler | 1 + *----------------------------------------------------------------------------- + * APB2 Prescaler | 1 + *----------------------------------------------------------------------------- + * APB1 Prescaler | 2 + *----------------------------------------------------------------------------- + * HSE Frequency(Hz) | 8000000 + *---------------------------------------------------------------------------- + * PLLMUL | 9 + *----------------------------------------------------------------------------- + * PREDIV | 1 + *----------------------------------------------------------------------------- + * USB Clock | ENABLE + *----------------------------------------------------------------------------- + * Flash Latency(WS) | 2 + *----------------------------------------------------------------------------- + * Prefetch Buffer | ON + *----------------------------------------------------------------------------- + *============================================================================= + ****************************************************************************** + * @attention + * + * <h2><center>© COPYRIGHT 2013 STMicroelectronics</center></h2> + * + * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License"); + * You may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.st.com/software_license_agreement_liberty_v2 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + ****************************************************************************** + */ +/** @addtogroup CMSIS + * @{ + */ + +/** @addtogroup stm32f30x_system + * @{ + */ + +/** @addtogroup STM32F30x_System_Private_Includes + * @{ + */ + +#include "stm32f30x.h" + +/** + * @} + */ + +/** @addtogroup STM32F30x_System_Private_TypesDefinitions + * @{ + */ + +/** + * @} + */ + +/** @addtogroup STM32F30x_System_Private_Defines + * @{ + */ +/*!< Uncomment the following line if you need to relocate your vector Table in + Internal SRAM. */ +/* #define VECT_TAB_SRAM */ +#define VECT_TAB_OFFSET 0x0 /*!< Vector Table base offset field. + This value must be a multiple of 0x200. */ +/** + * @} + */ + +/** @addtogroup STM32F30x_System_Private_Macros + * @{ + */ + +/** + * @} + */ + +/** @addtogroup STM32F30x_System_Private_Variables + * @{ + */ + + uint32_t SystemCoreClock = 72000000; + + __I uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9}; + +/** + * @} + */ + +/** @addtogroup STM32F30x_System_Private_FunctionPrototypes + * @{ + */ + +static void SetSysClock(void); + +/** + * @} + */ + +/** @addtogroup STM32F30x_System_Private_Functions + * @{ + */ + +/** + * @brief Setup the microcontroller system + * Initialize the Embedded Flash Interface, the PLL and update the + * SystemFrequency variable. + * @param None + * @retval None + */ +void SystemInit(void) +{ + /* FPU settings ------------------------------------------------------------*/ + #if (__FPU_PRESENT == 1) && (__FPU_USED == 1) + SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2)); /* set CP10 and CP11 Full Access */ + #endif + + /* Reset the RCC clock configuration to the default reset state ------------*/ + /* Set HSION bit */ + RCC->CR |= (uint32_t)0x00000001; + + /* Reset CFGR register */ + RCC->CFGR &= 0xF87FC00C; + + /* Reset HSEON, CSSON and PLLON bits */ + RCC->CR &= (uint32_t)0xFEF6FFFF; + + /* Reset HSEBYP bit */ + RCC->CR &= (uint32_t)0xFFFBFFFF; + + /* Reset PLLSRC, PLLXTPRE, PLLMUL and USBPRE bits */ + RCC->CFGR &= (uint32_t)0xFF80FFFF; + + /* Reset PREDIV1[3:0] bits */ + RCC->CFGR2 &= (uint32_t)0xFFFFFFF0; + + /* Reset USARTSW[1:0], I2CSW and TIMs bits */ + RCC->CFGR3 &= (uint32_t)0xFF00FCCC; + + /* Disable all interrupts */ + RCC->CIR = 0x00000000; + + /* Configure the System clock source, PLL Multiplier and Divider factors, + AHB/APBx prescalers and Flash settings ----------------------------------*/ + SetSysClock(); + +#ifdef VECT_TAB_SRAM + SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM. */ +#else + SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH. */ +#endif +} + +/** + * @brief Update SystemCoreClock variable according to Clock Register Values. + * The SystemCoreClock variable contains the core clock (HCLK), it can + * be used by the user application to setup the SysTick timer or configure + * other parameters. + * + * @note Each time the core clock (HCLK) changes, this function must be called + * to update SystemCoreClock variable value. Otherwise, any configuration + * based on this variable will be incorrect. + * + * @note - The system frequency computed by this function is not the real + * frequency in the chip. It is calculated based on the predefined + * constant and the selected clock source: + * + * - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(*) + * + * - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(**) + * + * - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(**) + * or HSI_VALUE(*) multiplied/divided by the PLL factors. + * + * (*) HSI_VALUE is a constant defined in stm32f30x.h file (default value + * 8 MHz) but the real value may vary depending on the variations + * in voltage and temperature. + * + * (**) HSE_VALUE is a constant defined in stm32f30x.h file (default value + * 8 MHz), user has to ensure that HSE_VALUE is same as the real + * frequency of the crystal used. Otherwise, this function may + * have wrong result. + * + * - The result of this function could be not correct when using fractional + * value for HSE crystal. + * + * @param None + * @retval None + */ +void SystemCoreClockUpdate (void) +{ + uint32_t tmp = 0, pllmull = 0, pllsource = 0, prediv1factor = 0; + + /* Get SYSCLK source -------------------------------------------------------*/ + tmp = RCC->CFGR & RCC_CFGR_SWS; + + switch (tmp) + { + case 0x00: /* HSI used as system clock */ + SystemCoreClock = HSI_VALUE; + break; + case 0x04: /* HSE used as system clock */ + SystemCoreClock = HSE_VALUE; + break; + case 0x08: /* PLL used as system clock */ + /* Get PLL clock source and multiplication factor ----------------------*/ + pllmull = RCC->CFGR & RCC_CFGR_PLLMULL; + pllsource = RCC->CFGR & RCC_CFGR_PLLSRC; + pllmull = ( pllmull >> 18) + 2; + + if (pllsource == 0x00) + { + /* HSI oscillator clock divided by 2 selected as PLL clock entry */ + SystemCoreClock = (HSI_VALUE >> 1) * pllmull; + } + else + { + prediv1factor = (RCC->CFGR2 & RCC_CFGR2_PREDIV1) + 1; + /* HSE oscillator clock selected as PREDIV1 clock entry */ + SystemCoreClock = (HSE_VALUE / prediv1factor) * pllmull; + } + break; + default: /* HSI used as system clock */ + SystemCoreClock = HSI_VALUE; + break; + } + /* Compute HCLK clock frequency ----------------*/ + /* Get HCLK prescaler */ + tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)]; + /* HCLK clock frequency */ + SystemCoreClock >>= tmp; +} + +/** + * @brief Configures the System clock source, PLL Multiplier and Divider factors, + * AHB/APBx prescalers and Flash settings + * @note This function should be called only once the RCC clock configuration + * is reset to the default reset state (done in SystemInit() function). + * @param None + * @retval None + */ +static void SetSysClock(void) +{ + __IO uint32_t StartUpCounter = 0, HSEStatus = 0; + +/******************************************************************************/ +/* PLL (clocked by HSE) used as System clock source */ +/******************************************************************************/ + + /* SYSCLK, HCLK, PCLK2 and PCLK1 configuration -----------*/ + /* Enable HSE */ + RCC->CR |= ((uint32_t)RCC_CR_HSEON); + + /* Wait till HSE is ready and if Time out is reached exit */ + do + { + HSEStatus = RCC->CR & RCC_CR_HSERDY; + StartUpCounter++; + } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT)); + + if ((RCC->CR & RCC_CR_HSERDY) != RESET) + { + HSEStatus = (uint32_t)0x01; + } + else + { + HSEStatus = (uint32_t)0x00; + } + + if (HSEStatus == (uint32_t)0x01) + { + /* Enable Prefetch Buffer and set Flash Latency */ + FLASH->ACR = FLASH_ACR_PRFTBE | (uint32_t)FLASH_ACR_LATENCY_1; + + /* HCLK = SYSCLK / 1 */ + RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1; + + /* PCLK2 = HCLK / 1 */ + RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1; + + /* PCLK1 = HCLK / 2 */ + RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV2; + + /* PLL configuration */ + RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLMULL)); + RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLXTPRE_PREDIV1 | RCC_CFGR_PLLMULL9); + + /* Enable PLL */ + RCC->CR |= RCC_CR_PLLON; + + /* Wait till PLL is ready */ + while((RCC->CR & RCC_CR_PLLRDY) == 0) + { + } + + /* Select PLL as system clock source */ + RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW)); + RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL; + + /* Wait till PLL is used as system clock source */ + while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)RCC_CFGR_SWS_PLL) + { + } + } + else + { /* If HSE fails to start-up, the application will have wrong clock + configuration. User can add here some code to deal with this error */ + } +} + +/** + * @} + */ + +/** + * @} + */ + +/** + * @} + */ + +/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/ + |