1.. _skiboot-5.9.4:
2
3=============
4skiboot-5.9.4
5=============
6
7skiboot 5.9.4 was released on Wednesday November 29th, 2017. It replaces
8:ref:`skiboot-5.9.3` as the current stable release in the 5.9.x series.
9
10Over :ref:`skiboot-5.9.3`, we have one NPU2/NVLink2 fix that works around
11a potential glitch (the one :ref:`skiboot-5.9.3` would hard crash on rather
12than let a system continue to run until it mysteriously crashed later on).
13
14That fix is in two parts:
15
16- npu2: hw-procedures: Change phy_rx_clock_sel values to recover from a
17  potential glitch.
18
19- npu2: hw-procedures: Manipulate IOVALID during training
20
21  Ensure that the IOVALID bit for this brick is raised at the start of
22  link training, in the reset_ntl procedure.
23
24  Then, to protect us from a glitch when the PHY clock turns off or gets
25  chopped, lower IOVALID for the duration of the phy_reset and
26  phy_rx_dccal procedures.
27