+config SPL_SYS_STDIO_DEREGISTER
+ bool "Allow deregistering stdio devices in SPL"
+ help
+ Generally there is no need to deregister stdio devices since they
+ are never deactivated. But if a stdio device is used which can be
+ removed (for example a USB keyboard) then this option can be
+ enabled to ensure this is handled correctly. This is very rarely
+ needed in SPL.
+
+config SYS_DEVICE_NULLDEV
+ bool "Enable a null device for stdio"
+ help
+ Enable creation of a "nulldev" stdio device. This allows silent
+ operation of the console by setting stdout to "nulldev". Enable
+ this to use a serial console under board control.
+