cmake: qemu: add rules for running the kernel under lldb

arch/x86_64/QEMU.cmake

@@ -1,5 +1,24 @@
 find_program(QEMU qemu-system-${TARGET_ARCH} REQUIRED)
+find_program(LLDB lldb REQUIRED)
 
 add_custom_target(run-kernel
-	COMMAND ${QEMU} -kernel $<TARGET_FILE:${kernel_name}>
-	DEPENDS ${kernel_name} ${bsp_name})
+	COMMAND
+		${QEMU}
+		-kernel $<TARGET_FILE:${kernel_name}>
+		-initrd ${sys_dir}/${bsp_name}
+		-m 1G -serial stdio
+		--append kernel.early-console=ttyS0
+	USES_TERMINAL
+	DEPENDS ${kernel_name} bsp)
+
+add_custom_target(debug-kernel
+	COMMAND
+		${QEMU}
+			-kernel $<TARGET_FILE:${kernel_name}>
+			-initrd ${sys_dir}/${bsp_name}
+			-m 1G -s -S &
+		${LLDB}
+			-o "file ${CMAKE_BINARY_DIR}/kernel/${kernel_name}.debug"
+			-o "gdb-remote localhost:1234"
+	USES_TERMINAL
+	DEPENDS ${kernel_name} bsp)