Failure to reach login screen - nouveau problem

[Peter Hillier-Brook <phb@hbsys.plus.com>]

Following an overnight shut down I couldn't reach the desktop manager
the following day. Running a live system I was able to extract the
following via 'dmesg'. Does anyone recognise this, or can offer a
pointer to the problem?
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

[    0.705479] nouveau E[  DEVICE][0000:01:00.0] unknown chipset, 0x124020a1
[    0.705515] nouveau E[     DRM] failed to create 0x80000080, -22
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Thanks in advance.

Peter HB