STM32F3: Remove dependence upon a specific flash vector table location

The STM32F3 cmsis_nvic code is currently checking for a specific flash
address when determining if the vector table is in flash or RAM.  By
changing the test to instead see if the vector table base is NOT set to
the RAM address, it simplifies the code, and removes the dependency on
the flash vectors being located at a specific address.  This becomes
important when adding a custom boot loader, which requires that the
flash vector table location in the mbed project be at a different
address.

Author: bscott-zebra

targets/TARGET_STM/TARGET_STM32F3/TARGET_STM32F302x8/device/cmsis_nvic.c

@@ -31,14 +31,13 @@
 #include "cmsis_nvic.h"
 
 #define NVIC_RAM_VECTOR_ADDRESS   (0x20000000)  // Vectors positioned at start of RAM
-#define NVIC_FLASH_VECTOR_ADDRESS (0x08000000)  // Initial vector position in flash
 
 void NVIC_SetVector(IRQn_Type IRQn, uint32_t vector) {
     uint32_t *vectors = (uint32_t *)SCB->VTOR;
     uint32_t i;
 
     // Copy and switch to dynamic vectors if the first time called
-    if (SCB->VTOR == NVIC_FLASH_VECTOR_ADDRESS) {
+    if (SCB->VTOR != NVIC_RAM_VECTOR_ADDRESS) {
         uint32_t *old_vectors = vectors;
         vectors = (uint32_t*)NVIC_RAM_VECTOR_ADDRESS;
         for (i=0; i<NVIC_NUM_VECTORS; i++) {

targets/TARGET_STM/TARGET_STM32F3/TARGET_STM32F303x8/device/cmsis_nvic.c

@@ -31,14 +31,13 @@
 #include "cmsis_nvic.h"
 
 #define NVIC_RAM_VECTOR_ADDRESS   (0x20000000)  // Vectors positioned at start of RAM
-#define NVIC_FLASH_VECTOR_ADDRESS (0x08000000)  // Initial vector position in flash
 
 void NVIC_SetVector(IRQn_Type IRQn, uint32_t vector) {
     uint32_t *vectors = (uint32_t *)SCB->VTOR;
     uint32_t i;
 
     // Copy and switch to dynamic vectors if the first time called
-    if (SCB->VTOR == NVIC_FLASH_VECTOR_ADDRESS) {
+    if (SCB->VTOR != NVIC_RAM_VECTOR_ADDRESS) {
         uint32_t *old_vectors = vectors;
         vectors = (uint32_t*)NVIC_RAM_VECTOR_ADDRESS;
         for (i=0; i<NVIC_NUM_VECTORS; i++) {

targets/TARGET_STM/TARGET_STM32F3/TARGET_STM32F303xC/device/cmsis_nvic.c

@@ -31,14 +31,13 @@
 #include "cmsis_nvic.h"
 
 #define NVIC_RAM_VECTOR_ADDRESS   (0x20000000)  // Vectors positioned at start of RAM
-#define NVIC_FLASH_VECTOR_ADDRESS (0x08000000)  // Initial vector position in flash
 
 void NVIC_SetVector(IRQn_Type IRQn, uint32_t vector) {
     uint32_t *vectors = (uint32_t *)SCB->VTOR;
     uint32_t i;
 
     // Copy and switch to dynamic vectors if the first time called
-    if (SCB->VTOR == NVIC_FLASH_VECTOR_ADDRESS) {
+    if (SCB->VTOR != NVIC_RAM_VECTOR_ADDRESS) {
         uint32_t *old_vectors = vectors;
         vectors = (uint32_t*)NVIC_RAM_VECTOR_ADDRESS;
         for (i=0; i<NVIC_NUM_VECTORS; i++) {

targets/TARGET_STM/TARGET_STM32F3/TARGET_STM32F303xE/device/cmsis_nvic.c

@@ -31,14 +31,13 @@
 #include "cmsis_nvic.h"
 
 #define NVIC_RAM_VECTOR_ADDRESS   (0x20000000)  // Vectors positioned at start of RAM
-#define NVIC_FLASH_VECTOR_ADDRESS (0x08000000)  // Initial vector position in flash
 
 void NVIC_SetVector(IRQn_Type IRQn, uint32_t vector) {
     uint32_t *vectors = (uint32_t *)SCB->VTOR;
     uint32_t i;
 
     // Copy and switch to dynamic vectors if the first time called
-    if (SCB->VTOR == NVIC_FLASH_VECTOR_ADDRESS) {
+    if (SCB->VTOR != NVIC_RAM_VECTOR_ADDRESS) {
         uint32_t *old_vectors = vectors;
         vectors = (uint32_t*)NVIC_RAM_VECTOR_ADDRESS;
         for (i=0; i<NVIC_NUM_VECTORS; i++) {

targets/TARGET_STM/TARGET_STM32F3/TARGET_STM32F334x8/device/cmsis_nvic.c

@@ -31,14 +31,13 @@
 #include "cmsis_nvic.h"
 
 #define NVIC_RAM_VECTOR_ADDRESS   (0x20000000)  // Vectors positioned at start of RAM
-#define NVIC_FLASH_VECTOR_ADDRESS (0x08000000)  // Initial vector position in flash
 
 void NVIC_SetVector(IRQn_Type IRQn, uint32_t vector) {
     uint32_t *vectors = (uint32_t *)SCB->VTOR;
     uint32_t i;
 
     // Copy and switch to dynamic vectors if the first time called
-    if (SCB->VTOR == NVIC_FLASH_VECTOR_ADDRESS) {
+    if (SCB->VTOR != NVIC_RAM_VECTOR_ADDRESS) {
         uint32_t *old_vectors = vectors;
         vectors = (uint32_t*)NVIC_RAM_VECTOR_ADDRESS;
         for (i=0; i<NVIC_NUM_VECTORS; i++) {