--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/TARGET_STM32F303xE/TARGET_NUCLEO_F303RE/system_clock.c Thu Oct 15 01:12:31 2020 +0200
@@ -0,0 +1,221 @@
+/* mbed Microcontroller Library
+* Copyright (c) 2006-2017 ARM Limited
+*
+* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+*
+* 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.
+*/
+
+/**
+ * This file configures the system clock as follows:
+ *-----------------------------------------------------------------------------
+ * System clock source | 1- USE_PLL_HSE_EXTC (external 8 MHz clock)
+ * | 2- USE_PLL_HSE_XTAL (external 8 MHz xtal)
+ * | 3- USE_PLL_HSI (internal 8 MHz)
+ *-----------------------------------------------------------------------------
+ * SYSCLK(MHz) | 72
+ * AHBCLK (MHz) | 72
+ * APB1CLK (MHz) | 36
+ * APB2CLK (MHz) | 72
+ * USB capable | YES
+ *-----------------------------------------------------------------------------
+ */
+
+
+#include "stm32f3xx.h"
+#include "mbed_error.h"
+
+// clock source is selected with CLOCK_SOURCE in json config
+#define USE_PLL_HSE_EXTC 0x8 // Use external clock (ST Link MCO)
+#define USE_PLL_HSE_XTAL 0x4 // Use external xtal (X3 on board - not provided by default)
+#define USE_PLL_HSI 0x2 // Use HSI internal clock
+
+#if ( ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) )
+uint8_t SetSysClock_PLL_HSE(uint8_t bypass);
+#endif /* ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) */
+
+#if ((CLOCK_SOURCE) & USE_PLL_HSI)
+uint8_t SetSysClock_PLL_HSI(void);
+#endif /* ((CLOCK_SOURCE) & USE_PLL_HSI) */
+
+/**
+ * @brief Setup the microcontroller system
+ * Initialize the FPU setting, vector table location and the PLL configuration is reset.
+ * @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 |= 0x00000001U;
+
+ /* Reset CFGR register */
+ RCC->CFGR &= 0xF87FC00CU;
+
+ /* Reset HSEON, CSSON and PLLON bits */
+ RCC->CR &= 0xFEF6FFFFU;
+
+ /* Reset HSEBYP bit */
+ RCC->CR &= 0xFFFBFFFFU;
+
+ /* Reset PLLSRC, PLLXTPRE, PLLMUL and USBPRE bits */
+ RCC->CFGR &= 0xFF80FFFFU;
+
+ /* Reset PREDIV1[3:0] bits */
+ RCC->CFGR2 &= 0xFFFFFFF0U;
+
+ /* Reset USARTSW[1:0], I2CSW and TIMs bits */
+ RCC->CFGR3 &= 0xFF00FCCCU;
+
+ /* Disable all interrupts */
+ RCC->CIR = 0x00000000U;
+}
+
+
+/**
+ * @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
+ */
+
+void SetSysClock(void)
+{
+#if ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC)
+ /* 1- Try to start with HSE and external clock */
+ if (SetSysClock_PLL_HSE(1) == 0)
+#endif
+ {
+#if ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL)
+ /* 2- If fail try to start with HSE and external xtal */
+ if (SetSysClock_PLL_HSE(0) == 0)
+#endif
+ {
+#if ((CLOCK_SOURCE) & USE_PLL_HSI)
+ /* 3- If fail start with HSI clock */
+ if (SetSysClock_PLL_HSI() == 0)
+#endif
+ {
+ {
+ error("SetSysClock failed\n");
+ }
+ }
+ }
+ }
+
+ /* Output clock on MCO2 pin(PC9) for debugging purpose */
+ //HAL_RCC_MCOConfig(RCC_MCO2, RCC_MCO2SOURCE_SYSCLK, RCC_MCODIV_4);
+}
+
+#if ( ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) )
+/******************************************************************************/
+/* PLL (clocked by HSE) used as System clock source */
+/******************************************************************************/
+uint8_t SetSysClock_PLL_HSE(uint8_t bypass)
+{
+ RCC_ClkInitTypeDef RCC_ClkInitStruct;
+ RCC_OscInitTypeDef RCC_OscInitStruct;
+ RCC_PeriphCLKInitTypeDef RCC_PeriphClkInit;
+
+ /* Enable HSE oscillator and activate PLL with HSE as source */
+ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
+ if (bypass == 0) {
+ RCC_OscInitStruct.HSEState = RCC_HSE_ON; /* External 8 MHz xtal on OSC_IN/OSC_OUT */
+ } else {
+ RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS; /* External 8 MHz clock on OSC_IN */
+ }
+ RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
+ RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
+ RCC_OscInitStruct.PLL.PREDIV = RCC_PREDIV_DIV1;
+ RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9; // 72 MHz (8 MHz * 9)
+ if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
+ return 0; // FAIL
+ }
+
+ /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers */
+ RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
+ RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; // 72 MHz
+ RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 72 MHz
+ RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2; // 36 MHz
+ RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; // 72 MHz
+ if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) {
+ return 0; // FAIL
+ }
+
+ RCC_PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
+ RCC_PeriphClkInit.USBClockSelection = RCC_USBCLKSOURCE_PLL_DIV1_5;
+ if (HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphClkInit) != HAL_OK) {
+ return 0; // FAIL
+ }
+
+ /* Output clock on MCO1 pin(PA8) for debugging purpose */
+ //if (bypass == 0)
+ // HAL_RCC_MCOConfig(RCC_MCO, RCC_MCOSOURCE_HSE, RCC_MCO_DIV2); // 4 MHz with xtal
+ //else
+ // HAL_RCC_MCOConfig(RCC_MCO, RCC_MCOSOURCE_HSE, RCC_MCO_DIV1); // 8 MHz with ext clock
+
+ return 1; // OK
+}
+#endif /* ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) */
+
+#if ((CLOCK_SOURCE) & USE_PLL_HSI)
+/******************************************************************************/
+/* PLL (clocked by HSI) used as System clock source */
+/******************************************************************************/
+uint8_t SetSysClock_PLL_HSI(void)
+{
+ RCC_ClkInitTypeDef RCC_ClkInitStruct;
+ RCC_OscInitTypeDef RCC_OscInitStruct;
+ RCC_PeriphCLKInitTypeDef RCC_PeriphClkInit;
+
+ /* Enable HSI oscillator and activate PLL with HSI as source */
+ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI | RCC_OSCILLATORTYPE_HSE;
+ RCC_OscInitStruct.HSIState = RCC_HSI_ON;
+ RCC_OscInitStruct.HSEState = RCC_HSE_OFF;
+ RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
+ RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
+ RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
+ RCC_OscInitStruct.PLL.PREDIV = RCC_PREDIV_DIV1;
+ RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9; // 72 MHz (8 MHz/1 * 9)
+ if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
+ return 0; // FAIL
+ }
+
+ /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers */
+ RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
+ RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; // 72 MHz
+ RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 72 MHz
+ RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2; // 36 MHz
+ RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; // 72 MHz
+ if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) {
+ return 0; // FAIL
+ }
+
+ RCC_PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
+ RCC_PeriphClkInit.USBClockSelection = RCC_USBCLKSOURCE_PLL_DIV1_5;
+ if (HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphClkInit) != HAL_OK) {
+ return 0; // FAIL
+ }
+
+ /* Output clock on MCO1 pin(PA8) for debugging purpose */
+ //HAL_RCC_MCOConfig(RCC_MCO, RCC_MCOSOURCE_HSI, RCC_MCO_DIV1); // 8 MHz
+
+ return 1; // OK
+}
+#endif /* ((CLOCK_SOURCE) & USE_PLL_HSI) */