Commits
James Hogan committed c3f43eec80d
tty/metag_da: Add console_poll module parameter Currently the metag_da console channel is write only, it doesn't get polled for incoming data. This is for performance & latency reasons as polling blocks the processor for a significant amount of time waiting for the JTAG probe to respond to the request and restart the thread. This means that the console channel cannot be used for a login prompt, so ttyDA2 is usually used instead. In a virtual environment with a virtual DA such as QEMU however the polling is much cheaper as the request can be handled immediately. It is useful to be able to enable polling in such an environment in order to get both the kernel log and a usable login prompt on the same DA channel. Add a console_poll module parameter which allows polling to be enabled for the console channel. It defaults to off as that is the current behaviour for good reason on real hardware. It can be enabled by appending metag_da.console_poll to the kernel command line. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Jiri Slaby <jslaby@suse.cz> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>