1 /**
2   ******************************************************************************
3   * @file    system_stm32wbxx.c
4   * @author  MCD Application Team
5   * @brief   CMSIS Cortex Device Peripheral Access Layer System Source File
6   *
7   *   This file provides two functions and one global variable to be called from
8   *   user application:
9   *      - SystemInit(): This function is called at startup just after reset and
10   *                      before branch to main program. This call is made inside
11   *                      the "startup_stm32wbxx.s" file.
12   *
13   *      - SystemCoreClock variable: Contains the core clock (HCLK), it can be used
14   *                                  by the user application to setup the SysTick
15   *                                  timer or configure other parameters.
16   *
17   *      - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must
18   *                                 be called whenever the core clock is changed
19   *                                 during program execution.
20   *
21   *   After each device reset the MSI (4 MHz) is used as system clock source.
22   *   Then SystemInit() function is called, in "startup_stm32wbxx.s" file, to
23   *   configure the system clock before to branch to main program.
24   *
25   *   This file configures the system clock as follows:
26   *=============================================================================
27   *-----------------------------------------------------------------------------
28   *        System Clock source                    | MSI
29   *-----------------------------------------------------------------------------
30   *        SYSCLK(Hz)                             | 4000000
31   *-----------------------------------------------------------------------------
32   *        HCLK(Hz)                               | 4000000
33   *-----------------------------------------------------------------------------
34   *        AHB Prescaler                          | 1
35   *-----------------------------------------------------------------------------
36   *        APB1 Prescaler                         | 1
37   *-----------------------------------------------------------------------------
38   *        APB2 Prescaler                         | 1
39   *-----------------------------------------------------------------------------
40   *        PLL_M                                  | 1
41   *-----------------------------------------------------------------------------
42   *        PLL_N                                  | 8
43   *-----------------------------------------------------------------------------
44   *        PLL_P                                  | 7
45   *-----------------------------------------------------------------------------
46   *        PLL_Q                                  | 2
47   *-----------------------------------------------------------------------------
48   *        PLL_R                                  | 2
49   *-----------------------------------------------------------------------------
50   *        PLLSAI1_P                              | NA
51   *-----------------------------------------------------------------------------
52   *        PLLSAI1_Q                              | NA
53   *-----------------------------------------------------------------------------
54   *        PLLSAI1_R                              | NA
55   *-----------------------------------------------------------------------------
56   *        Require 48MHz for USB OTG FS,          | Disabled
57   *        SDIO and RNG clock                     |
58   *-----------------------------------------------------------------------------
59   *=============================================================================
60   ******************************************************************************
61   * @attention
62   *
63   * Copyright (c) 2019-2021 STMicroelectronics.
64   * All rights reserved.
65   *
66   * This software is licensed under terms that can be found in the LICENSE file
67   * in the root directory of this software component.
68   * If no LICENSE file comes with this software, it is provided AS-IS.
69   *
70   ******************************************************************************
71   */
72 
73 /** @addtogroup CMSIS
74   * @{
75   */
76 
77 /** @addtogroup stm32WBxx_system
78   * @{
79   */
80 
81 /** @addtogroup stm32WBxx_System_Private_Includes
82   * @{
83   */
84 
85 #include "stm32wbxx.h"
86 
87 #if !defined  (HSE_VALUE)
88 #define HSE_VALUE    (32000000UL) /*!< Value of the External oscillator in Hz */
89 #endif /* HSE_VALUE */
90 
91 #if !defined  (MSI_VALUE)
92 #define MSI_VALUE    (4000000UL) /*!< Value of the Internal oscillator in Hz*/
93 #endif /* MSI_VALUE */
94 
95 #if !defined  (HSI_VALUE)
96 #define HSI_VALUE    (16000000UL) /*!< Value of the Internal oscillator in Hz*/
97 #endif /* HSI_VALUE */
98 
99 #if !defined  (LSI_VALUE)
100 #define LSI_VALUE  (32000UL)       /*!< Value of LSI in Hz*/
101 #endif /* LSI_VALUE */
102 
103 #if !defined  (LSE_VALUE)
104 #if defined(STM32WB5Mxx)
105   #define LSE_VALUE    32774U     /*!< Value of the LSE oscillator in Hz */
106 #else
107   #define LSE_VALUE    32768U     /*!< Value of the LSE oscillator in Hz */
108 #endif /* STM32WB5Mxx */
109 #endif /* LSE_VALUE */
110 
111 /**
112   * @}
113   */
114 
115 /** @addtogroup STM32WBxx_System_Private_TypesDefinitions
116   * @{
117   */
118 
119 /**
120   * @}
121   */
122 
123 /** @addtogroup STM32WBxx_System_Private_Defines
124   * @{
125   */
126 
127 /* Note: Following vector table addresses must be defined in line with linker
128          configuration. */
129 /*!< Uncomment the following line if you need to relocate CPU1 CM4 and/or CPU2
130      CM0+ vector table anywhere in Sram or Flash. Else vector table will be kept
131      at address 0x00 which correspond to automatic remap of boot address selected */
132 /* #define USER_VECT_TAB_ADDRESS */
133 #if defined(USER_VECT_TAB_ADDRESS)
134 /*!< Uncomment this line for user vector table remap in Sram else user remap
135      will be done in Flash. */
136 /* #define VECT_TAB_SRAM */
137 #if defined(VECT_TAB_SRAM)
138 #define VECT_TAB_BASE_ADDRESS   SRAM1_BASE      /*!< Vector Table base address field.
139                                                      This value must be a multiple of 0x200. */
140 #define VECT_TAB_OFFSET         0x00000000U     /*!< Vector Table base offset field.
141                                                      This value must be a multiple of 0x200. */
142 #else
143 #define VECT_TAB_BASE_ADDRESS   FLASH_BASE      /*!< Vector Table base address field.
144                                                      This value must be a multiple of 0x200. */
145 #define VECT_TAB_OFFSET         0x00000000U     /*!< Vector Table base offset field.
146                                                      This value must be a multiple of 0x200. */
147 #endif /* VECT_TAB_SRAM */
148 #endif /* USER_VECT_TAB_ADDRESS */
149 
150 /**
151   * @}
152   */
153 
154 /** @addtogroup STM32WBxx_System_Private_Macros
155   * @{
156   */
157 
158 /**
159   * @}
160   */
161 
162 /** @addtogroup STM32WBxx_System_Private_Variables
163   * @{
164   */
165 /* The SystemCoreClock variable is updated in three ways:
166     1) by calling CMSIS function SystemCoreClockUpdate()
167     2) by calling HAL API function HAL_RCC_GetHCLKFreq()
168     3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency
169        Note: If you use this function to configure the system clock; then there
170              is no need to call the 2 first functions listed above, since SystemCoreClock
171              variable is updated automatically.
172 */
173 uint32_t SystemCoreClock = 4000000UL ; /*CPU1: M4 on MSI clock after startup (4MHz)*/
174 
175 const uint32_t AHBPrescTable[16UL] = {1UL, 3UL, 5UL, 1UL, 1UL, 6UL, 10UL, 32UL, 2UL, 4UL, 8UL, 16UL, 64UL, 128UL, 256UL, 512UL};
176 
177 const uint32_t APBPrescTable[8UL]  = {0UL, 0UL, 0UL, 0UL, 1UL, 2UL, 3UL, 4UL};
178 
179 const uint32_t MSIRangeTable[16UL] = {100000UL, 200000UL, 400000UL, 800000UL, 1000000UL, 2000000UL, \
180                                       4000000UL, 8000000UL, 16000000UL, 24000000UL, 32000000UL, 48000000UL, 0UL, 0UL, 0UL, 0UL
181                                      }; /* 0UL values are incorrect cases */
182 
183 #if defined(STM32WB55xx) || defined(STM32WB5Mxx) || defined(STM32WB35xx) || defined (STM32WB15xx) || defined (STM32WB1Mxx)
184 const uint32_t SmpsPrescalerTable[4UL][6UL] = {{1UL, 3UL, 2UL, 2UL, 1UL, 2UL}, \
185   {2UL, 6UL, 4UL, 3UL, 2UL, 4UL}, \
186   {4UL, 12UL, 8UL, 6UL, 4UL, 8UL}, \
187   {4UL, 12UL, 8UL, 6UL, 4UL, 8UL}
188 };
189 #endif /* STM32WB55xx || STM32WB5Mxx || STM32WB35xx || STM32WB15xx || STM32WB1Mxx */
190 
191 /**
192   * @}
193   */
194 
195 /** @addtogroup STM32WBxx_System_Private_FunctionPrototypes
196   * @{
197   */
198 
199 /**
200   * @}
201   */
202 
203 /** @addtogroup STM32WBxx_System_Private_Functions
204   * @{
205   */
206 
207 /**
208   * @brief  Setup the microcontroller system.
209   * @param  None
210   * @retval None
211   */
SystemInit(void)212 void SystemInit(void)
213 {
214 #if defined(USER_VECT_TAB_ADDRESS)
215   /* Configure the Vector Table location add offset address ------------------*/
216   SCB->VTOR = VECT_TAB_BASE_ADDRESS | VECT_TAB_OFFSET;
217 #endif /* USER_VECT_TAB_ADDRESS */
218 
219   /* FPU settings ------------------------------------------------------------*/
220 #if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
221   SCB->CPACR |= ((3UL << (10UL * 2UL)) | (3UL << (11UL * 2UL))); /* set CP10 and CP11 Full Access */
222 #endif /* FPU */
223 
224   /* Reset the RCC clock configuration to the default reset state ------------*/
225   /* Set MSION bit */
226   RCC->CR |= RCC_CR_MSION;
227 
228   /* Reset CFGR register */
229   RCC->CFGR = 0x00070000U;
230 
231   /* Reset PLLSAI1ON, PLLON, HSECSSON, HSEON, HSION, and MSIPLLON bits */
232   RCC->CR &= (uint32_t)0xFAF6FEFBU;
233 
234   /*!< Reset LSI1 and LSI2 bits */
235   RCC->CSR &= (uint32_t)0xFFFFFFFAU;
236 
237   /*!< Reset HSI48ON  bit */
238   RCC->CRRCR &= (uint32_t)0xFFFFFFFEU;
239 
240   /* Reset PLLCFGR register */
241   RCC->PLLCFGR = 0x22041000U;
242 
243 #if defined(STM32WB55xx) || defined(STM32WB5Mxx)
244   /* Reset PLLSAI1CFGR register */
245   RCC->PLLSAI1CFGR = 0x22041000U;
246 #endif /* STM32WB55xx || STM32WB5Mxx */
247 
248   /* Reset HSEBYP bit */
249   RCC->CR &= 0xFFFBFFFFU;
250 
251   /* Disable all interrupts */
252   RCC->CIER = 0x00000000;
253 }
254 
255 /**
256   * @brief  Update SystemCoreClock variable according to Clock Register Values.
257   *         The SystemCoreClock variable contains the core clock (HCLK), it can
258   *         be used by the user application to setup the SysTick timer or configure
259   *         other parameters.
260   *
261   * @note   Each time the core clock (HCLK) changes, this function must be called
262   *         to update SystemCoreClock variable value. Otherwise, any configuration
263   *         based on this variable will be incorrect.
264   *
265   * @note   - The system frequency computed by this function is not the real
266   *           frequency in the chip. It is calculated based on the predefined
267   *           constant and the selected clock source:
268   *
269   *           - If SYSCLK source is MSI, SystemCoreClock will contain the MSI_VALUE(*)
270   *
271   *           - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(**)
272   *
273   *           - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(***)
274   *
275   *           - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(***)
276   *             or HSI_VALUE(*) or MSI_VALUE(*) multiplied/divided by the PLL factors.
277   *
278   *         (*) MSI_VALUE is a constant defined in stm32wbxx_hal.h file (default value
279   *             4 MHz) but the real value may vary depending on the variations
280   *             in voltage and temperature.
281   *
282   *         (**) HSI_VALUE is a constant defined in stm32wbxx_hal_conf.h file (default value
283   *              16 MHz) but the real value may vary depending on the variations
284   *              in voltage and temperature.
285   *
286   *         (***) HSE_VALUE is a constant defined in stm32wbxx_hal_conf.h file (default value
287   *              32 MHz), user has to ensure that HSE_VALUE is same as the real
288   *              frequency of the crystal used. Otherwise, this function may
289   *              have wrong result.
290   *
291   *         - The result of this function could be not correct when using fractional
292   *           value for HSE crystal.
293   *
294   * @param  None
295   * @retval None
296   */
SystemCoreClockUpdate(void)297 void SystemCoreClockUpdate(void)
298 {
299   uint32_t tmp, msirange, pllvco, pllr, pllsource, pllm;
300 
301   /* Get MSI Range frequency--------------------------------------------------*/
302 
303   /*MSI frequency range in Hz*/
304   msirange = MSIRangeTable[(RCC->CR & RCC_CR_MSIRANGE) >> RCC_CR_MSIRANGE_Pos];
305 
306   /* Get SYSCLK source -------------------------------------------------------*/
307   switch (RCC->CFGR & RCC_CFGR_SWS)
308   {
309     case 0x00: /* MSI used as system clock source */
310       SystemCoreClock = msirange;
311       break;
312 
313     case 0x04: /* HSI used as system clock source */
314       /* HSI used as system clock source */
315       SystemCoreClock = HSI_VALUE;
316       break;
317 
318     case 0x08:  /* HSE used as system clock source */
319       SystemCoreClock = HSE_VALUE;
320       break;
321 
322     case 0x0C: /* PLL used as system clock  source */
323       /* PLL_VCO = (HSE_VALUE or HSI_VALUE or MSI_VALUE/ PLLM) * PLLN
324          SYSCLK = PLL_VCO / PLLR
325          */
326       pllsource = (RCC->PLLCFGR & RCC_PLLCFGR_PLLSRC);
327       pllm = ((RCC->PLLCFGR & RCC_PLLCFGR_PLLM) >> RCC_PLLCFGR_PLLM_Pos) + 1UL ;
328 
329       if (pllsource == 0x02UL) /* HSI used as PLL clock source */
330       {
331         pllvco = (HSI_VALUE / pllm);
332       }
333       else if (pllsource == 0x03UL) /* HSE used as PLL clock source */
334       {
335         pllvco = (HSE_VALUE / pllm);
336       }
337       else /* MSI used as PLL clock source */
338       {
339         pllvco = (msirange / pllm);
340       }
341 
342       pllvco = pllvco * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> RCC_PLLCFGR_PLLN_Pos);
343       pllr = (((RCC->PLLCFGR & RCC_PLLCFGR_PLLR) >> RCC_PLLCFGR_PLLR_Pos) + 1UL);
344 
345       SystemCoreClock = pllvco / pllr;
346       break;
347 
348     default:
349       SystemCoreClock = msirange;
350       break;
351   }
352 
353   /* Compute HCLK clock frequency --------------------------------------------*/
354   /* Get HCLK1 prescaler */
355   tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> RCC_CFGR_HPRE_Pos)];
356 
357   /* HCLK clock frequency */
358   SystemCoreClock = SystemCoreClock / tmp;
359 }
360 
361 
362 /**
363   * @}
364   */
365 
366 /**
367   * @}
368   */
369 
370 /**
371   * @}
372   */
373