adding cpu core .mk for makefile

fix cortex m33 for nrf5340 dk

examples/make.mk

@@ -2,6 +2,8 @@
 # Common make definition for all examples
 # ---------------------------------------
 
+TOOLCHAIN ?= gcc
+
 #-------------- TOP and CURRENT_PATH ------------
 
 # Set TOP to be the path to get from the current directory (where make was
@@ -75,6 +77,7 @@ else
 endif
 
 #-------------- Cross Compiler  ------------
+
 # Can be set by board, default to ARM GCC
 CROSS_COMPILE ?= arm-none-eabi-
 

hw/bsp/nrf/boards/pca10095/board.mk

@@ -1,3 +1,4 @@
+CPU_CORE = cortex-m33
 MCU_VARIANT = nrf5340_application
 CFLAGS += -DNRF5340_XXAA -DNRF5340_XXAA_APPLICATION
 

hw/bsp/nrf/family.mk

@@ -3,13 +3,12 @@ DEPS_SUBMODULES += lib/CMSIS_5 hw/mcu/nordic/nrfx
 
 include $(TOP)/$(BOARD_PATH)/board.mk
 
+CPU_CORE ?= cortex-m4
+
+include $(TOP)/tools/make/cpu/$(CPU_CORE).mk
+
 CFLAGS += \
   -flto \
-  -mthumb \
-  -mabi=aapcs \
-  -mcpu=cortex-m4 \
-  -mfloat-abi=hard \
-  -mfpu=fpv4-sp-d16 \
   -DCFG_TUSB_MCU=OPT_MCU_NRF5X \
   -DCONFIG_GPIO_AS_PINRESET
 

tools/make/cpu/cortex-m33.mk

@@ -0,0 +1,11 @@
+ifeq ($(TOOLCHAIN),gcc)
+  CFLAGS += \
+    -mthumb \
+    -mcpu=cortex-m33 \
+    -mfloat-abi=hard \
+    -mfpu=fpv5-d16 \
+
+  #set(FREERTOS_PORT GCC_ARM_CM33_NONSECURE CACHE INTERNAL "")
+else ifeq ($(TOOLCHAIN),iar)
+  # TODO support IAR
+endif

tools/make/cpu/cortex-m4.mk

@@ -0,0 +1,11 @@
+ifeq ($(TOOLCHAIN),gcc)
+  CFLAGS += \
+    -mthumb \
+    -mcpu=cortex-m4 \
+    -mfloat-abi=hard \
+    -mfpu=fpv4-sp-d16 \
+
+  #set(FREERTOS_PORT GCC_ARM_CM4F CACHE INTERNAL "")
+else ifeq ($(TOOLCHAIN),iar)
+  # TODO support IAR
+endif

tools/make/cpu/cortex-m7.mk

@@ -0,0 +1,11 @@
+ifeq ($(TOOLCHAIN),gcc)
+  CFLAGS += \
+    -mthumb \
+    -mcpu=cortex-m7 \
+    -mfloat-abi=hard \
+    -mfpu=fpv5-d16 \
+
+  #set(FREERTOS_PORT GCC_ARM_CM7 CACHE INTERNAL "")
+else ifeq ($(TOOLCHAIN),iar)
+  # TODO support IAR
+endif