[NUCLEO_F302R8] Use mbed_sdk_init() to update the SystemCoreClock variable.

Definitely the best solution...

libraries/mbed/targets/cmsis/TARGET_STM/TARGET_NUCLEO_F302R8/TOOLCHAIN_ARM_MICRO/stm32f302x8.sct

@@ -37,8 +37,7 @@ LR_IROM1 0x08000000 0x10000  {    ; load region size_region
   }
 
   ; 98 vectors (16 core + 82 peripheral) * 4 bytes = 392 bytes to reserve (0x188)
-  ; + 4 more bytes reserved for the SystemCoreClock variable
+  RW_IRAM1 (0x20000000+0x188) (0x4000-0x188)  {  ; RW data
-  RW_IRAM1 (0x20000000+(0x188+4)) (0x4000-(0x188+4))  {  ; RW data
    .ANY (+RW +ZI)
   }
 

libraries/mbed/targets/cmsis/TARGET_STM/TARGET_NUCLEO_F302R8/TOOLCHAIN_ARM_STD/stm32f302x8.sct

@@ -37,8 +37,7 @@ LR_IROM1 0x08000000 0x10000  {    ; load region size_region
   }
 
   ; 98 vectors (16 core + 82 peripheral) * 4 bytes = 392 bytes to reserve (0x188)
-  ; + 4 more bytes reserved for the SystemCoreClock variable
+  RW_IRAM1 (0x20000000+0x188) (0x4000-0x188)  {  ; RW data
-  RW_IRAM1 (0x20000000+(0x188+4)) (0x4000-(0x188+4))  {  ; RW data
    .ANY (+RW +ZI)
   }
 

libraries/mbed/targets/cmsis/TARGET_STM/TARGET_NUCLEO_F302R8/system_stm32f30x.c

@@ -141,10 +141,7 @@
   * @{
   */
 
-// [TODO] Do the same for other compilers
+uint32_t SystemCoreClock = 64000000; /* Default with HSI. Will be updated if HSE is used */
-// Warning: the RAM is initialized AFTER the SetSysClock function is called.
-// This variable must be placed outside the initialized section (see scatter file).
-uint32_t SystemCoreClock __attribute__((at(0x20000188))) = 64000000; /* Default with HSI. Will be updated if HSE is used */
 
 __I uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
 
@@ -361,11 +358,15 @@ uint8_t SetSysClock_PLL_HSE(uint8_t bypass)
   __IO uint32_t HSEStatus = 0;
 
   /* Bypass HSE: can be done only if HSE is OFF */
+  RCC->CR &= ((uint32_t)~RCC_CR_HSEON); /* To be sure HSE is OFF */  
   if (bypass != 0)
   {
-    RCC->CR &= ((uint32_t)~RCC_CR_HSEON); /* To be sure HSE is OFF */
     RCC->CR |= ((uint32_t)RCC_CR_HSEBYP);
   }
+  else
+  {
+    RCC->CR &= ((uint32_t)~RCC_CR_HSEBYP);
+  }
   
   /* Enable HSE */
   RCC->CR |= ((uint32_t)RCC_CR_HSEON);
@@ -412,7 +413,6 @@ uint8_t SetSysClock_PLL_HSE(uint8_t bypass)
     {
     }
 
-    SystemCoreClock = 72000000;
     return 1; // OK
   }
   else
@@ -460,7 +460,6 @@ uint8_t SetSysClock_PLL_HSI(void)
   {
   }
 
-  SystemCoreClock = 64000000;
   return 1; // OK
 }
 

libraries/mbed/targets/hal/TARGET_STM/TARGET_NUCLEO_F302R8/mbed_overrides.c

@@ -0,0 +1,35 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2014, STMicroelectronics
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. Neither the name of STMicroelectronics nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+extern void SystemCoreClockUpdate(void); 
+
+// This function is called after RAM initialization and before main.
+void mbed_sdk_init() {
+    // Update the SystemCoreClock variable.
+    SystemCoreClockUpdate();
+}