Add debug target

Makefile

@@ -4,6 +4,7 @@ CROSS=aarch64-linux-gnu-
 CC=$(CROSS)gcc
 LD=$(CROSS)ld
 CFLAGS=-Wall -Wextra -ffreestanding -march=armv8-a+crc -mcpu=cortex-a53
+DEBUG_FLAGS += -g -Og -DDEBUG -fno-omit-frame-pointer -fno-inline
 LDSCRIPT=rpi3.ld
 
 OBJS=crt0.o uart.o hello.o
@@ -13,20 +14,26 @@ csrc=$(wildcard *.c)
 cobj=$(csrc:%.c=%.o)
 deps=$(csrc:%.c=%.d) $(gasmsrc:%.S=%.d)
 
-all:kernel.bin
+KERNEL=kernel.bin
+
+all:$(KERNEL)
 
 kernel.elf: $(cobj) $(gasmobj) $(LDSCRIPT)
-	$(LD) $(LDFLAGS) -o $@ $(cobj) $(gasmobj) -T$(LDSCRIPT) -Map kernel.map
+	$(LD) $(LDFLAGS) -o $@ $(gasmobj) $(cobj) -T$(LDSCRIPT) -Map kernel.map
 
-kernel.bin: kernel.elf
+$(KERNEL): kernel.elf
 	$(CROSS)objcopy -O binary $< $@
 
 clean:
 	rm -rf $(cobj) $(gasmobj) $(deps) *.bin *.elf *.map
 
-run: kernel.bin
+run: $(KERNEL)
 	qemu-system-aarch64 -machine raspi3b -kernel $<
 
+debug: CFLAGS += $(DEBUG_FLAGS)
+debug: CXXFLAGS += $(DEBUG_FLAGS)
+debug:$(KERNEL)
+	aarch64-linux-gnu-gdb -q -x debug.gdb
 
 
 ifneq ($(MAKECMDGOALS),clean)

debug.gdb

@@ -0,0 +1,3 @@
+#add-symbol-file kernel.map
+file kernel.elf
+target remote | qemu-system-aarch64 -machine raspi3b  -S -gdb stdio -kernel kernel.bin