Merge pull request #14 from treymarc/fpu

use hardware fpu with target stm32f30x

Makefile

@@ -60,7 +60,7 @@ INCLUDE_DIRS := $(INCLUDE_DIRS) \
 
 LD_SCRIPT	 = $(ROOT)/stm32_flash_f303.ld
 
-ARCH_FLAGS	 = -mthumb -mcpu=cortex-m4
+ARCH_FLAGS	 = -mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16 
 DEVICE_FLAGS = -DSTM32F303xC
 TARGET_FLAGS = -D$(TARGET)
 ifeq ($(TARGET),CHEBUZZF3)

src/drivers/system_common.c

@@ -59,6 +59,12 @@ uint32_t millis(void)
 
 void systemInit(bool overclock)
 {
+
+#ifdef STM32F303xC
+    // start fpu
+    SCB->CPACR = (0x3 << (10*2)) | (0x3 << (11*2));
+#endif
+
     struct {
         GPIO_TypeDef *gpio;
         gpio_config_t cfg;