# Targets for running and debugging in Qemu/KVM

QEMUCPUS ?= 4
INITRD ?= /dev/null

# Switch to curses if no graphical output is available
ifeq ($(DISPLAY),)
	export QEMUDISPLAY    ?= curses
else
# Macos display
	ifeq ($(shell uname),Darwin)
		export QEMUDISPLAY    ?= cocoa
	else
		export QEMUDISPLAY    ?= gtk
	endif
endif

export QEMUEXTRAFLAGS ?=

# Architecture Specific flags
QEMUFLAGS += -k en-us -machine pcspk-audiodev=pa -d guest_errors -m 2048
# Macos sound
ifeq ($(shell uname),Darwin)
	QEMUFLAGS += -audiodev coreaudio,id=pa
else
	QEMUFLAGS += -audiodev pa,id=pa
endif
DBGKERNEL ?= $(KERNEL64)
DBGARCH ?= i386:x86-64
QEMU ?= qemu-system-x86_64
QEMUKERNEL ?= -kernel $(KERNEL) -initrd $(INITRD)
KVMFLAGS = -enable-kvm -cpu host
QEMUDBGFLAGS = -no-shutdown -no-reboot

GDB = $(PREFIX)gdb
ifneq ($(XDG_RUNTIME_DIR),)
	# We should prefer using domain sockets in a private directory
	GDBPORT ?= $(XDG_RUNTIME_DIR)/stubs-gdb.sock
else
	# but fall back to PID + 1024, which should be an unprivileged unique port on single- and multiuser systems
	GDBPORT ?= :$(shell echo $$(($$(id -u) + 1024)))
endif
ifneq ($(findstring /,$(GDBPORT)),)
	QEMUGDB = -chardev socket,path=${GDBPORT},server=on,wait=off,id=gdb0 -gdb chardev:gdb0
else
	QEMUGDB = -gdb tcp:${GDBPORT}
endif
# (gdb itself supports either :port or a path as target)

qemu: all
	@echo "QEMU		${KERNEL}"
	${VERBOSE} $(QEMU) $(QEMUKERNEL) $(QEMUGDB) -display ${QEMUDISPLAY} -smp $(QEMUCPUS) $(QEMUFLAGS) ${QEMUEXTRAFLAGS}

# Runs StuBS in Qemu with with hardware accelerations (KVM support) enabled
# The started emulator provides several virtual CPUs that execute in parallel.
kvm: all
	@echo "KVM		${KERNEL}"
	${VERBOSE} ${QEMU}  $(QEMUKERNEL) $(QEMUGDB) -display ${QEMUDISPLAY} -smp $(QEMUCPUS) $(QEMUFLAGS) ${QEMUEXTRAFLAGS} $(KVMFLAGS)

# Execute Qemu with activated GDB stub and directly connect GDB to the spawned Qemu.
gdb: all
	${VERBOSE} $(GDB) "$(DBGKERNEL)" \
		-ex "set arch $(DBGARCH)" \
		-ex "target remote | exec $(QEMU) -gdb stdio $(QEMUKERNEL) -smp $(QEMUCPUS) -S $(QEMUFLAGS) $(DBGFLAGS)"

################################################################
# Rekursive Targets: Setzen einzelner QEMU Paramter
################################################################

################################################################
# Debugging mit GDB
# Sinnvoll anwendbar mit den Targets: qemu, kvm, *-curses, *-serial
%-gdb:
	${VERBOSE} ${MAKE} QEMUEXTRAFLAGS="${QEMUEXTRAFLAGS} -S" $*

# um sich mit GDB auf dem Standardport zu verbinden
connect-gdb:
	${VERBOSE} gdb -ex "target remote ${GDBPORT}" $(DBGKERNEL)

################################################################
# Eine -display Variante erzwingen
%-curses:
	${VERBOSE} ${MAKE} QEMUDISPLAY="curses" QEMUSERIAL="vc:80Cx24C" $*

%-x11:
	${VERBOSE} ${MAKE} QEMUDISPLAY=gtk $*

################################################################
# Serial-Ausgabe
QEMUSERIAL ?= vc:80Cx24C
QEMUFLAGS += -serial $(QEMUSERIAL)
%-serial:
	@echo "HINT: C-a x: Terminate QEMU; C-a c: Open QEMU console"
	${VERBOSE} ${MAKE} QEMUSERIAL=mon:stdio $*

# Help for Qemu targets
help::
	@$(echo) "System Emulation\n" \
		"	\e[3mqemu\e[0m     Starts $(PROJECT) in QEMU\n" \
		"	         Due to the internal design of QEMU, some things (especially\n" \
		"	         race conditions) might behave different compared to hardware!\n\n" \
		"	\e[3mkvm\e[0m      Starts $(PROJECT) in KVM, a hardware-accelerated virtual machine\n\n" \
		"	\e[3m*-serial\e[0m Redirect the serial console to stdout (e.g., qemu-serial, kvm-serial)\n\n" \
		"	\e[3m*-curses\e[0m   Use QEMU's curses interface (e.g., qemu-curses).\n"\
		"	\e[3m*-x11\e[0m      Use QEMU's GTK interface (e.g., qemu-x11).\n\n"\
		"	\e[3m*-gdb\e[0m    Start Simulator with internal GDB stub and wait for a GDB\n" \
		"	         to attach. (e.g., qemu-gdb)\n" \
		"	\e[3mconnect-gdb\e[0m    Connect to waiting GDB. Execute in a second terminal!\n\n"\

# Phony targets
.PHONY: qemu kvm help