[BOOT] Multiboot compliant kernel which runs 64 bit code

kernel/Makefile

@@ -0,0 +1,71 @@
+#
+# Makefile for mittos64 kernel
+# (c) Thomas Lovén 2016-2017
+# mittos64@thomasloven.com
+#
+
+ifeq ($(MITTOS64),)
+  $(error Build environment is not activated. Please source activate)
+endif
+
+
+# Find all source files and corresponding object files
+KERNEL_SRC := $(wildcard **/*.[cS])
+KERNEL_OBJS := $(addprefix obj/,$(patsubst %,%.o,$(basename $(KERNEL_SRC))))
+
+# Kernel object file
+KERNEL := obj/boot/kernel
+
+
+# Default compilation flags
+CFLAGS ?= -Wall -Wextra
+CFLAGS += -ffreestanding -mcmodel=large
+CPPFLAGS += -Iinclude
+# Optimize only if not debugging
+ifdef NDEBUG
+CFLAGS += -O2
+CPPFLAGS += -DNDEBUG
+else
+CFLAGS += -ggdb -O0
+ASFLAGS += -ggdb
+endif
+
+KERNEL_DEP := $(KERNEL_OBJS:.o=.d)
+DEPFLAGS = -MT $@ -MMD -MP -MF obj/$*.d
+
+all: $(KERNEL)
+
+# Make sure the object directories exist
+OBJ_DIRS := $(sort $(dir $(KERNEL_OBJS)))
+$(KERNEL_OBJS): | $(OBJ_DIRS)
+$(OBJ_DIRS):
+	mkdir -p $@
+
+# The kernel needs some special flags
+$(KERNEL): LDFLAGS += -n -nostdlib -T Link.ld
+$(KERNEL): LDLIBS := -lgcc
+$(KERNEL): $(KERNEL_OBJS)
+	$(LINK.c) $^ -o $@
+
+# Use the default make compilation rules
+obj/%.o: %.c obj/%.d
+	$(COMPILE.c) $(DEPFLAGS) $< -o $@
+obj/%.o: %.S obj/%.d
+	$(COMPILE.S) $(DEPFLAGS) $< -o $@
+obj/%.d: ;
+
+# For installing stuff
+${SYSROOT}/%: obj/%
+	mkdir -p $(dir $@)
+	cp $< $@
+
+install-kernel: ${SYSROOT}/boot/kernel
+
+install: install-kernel
+
+clean:
+	rm -rf obj/
+
+-include $(KERNEL_DEP)
+
+.PHONY: all clean install install-kernel