skiboot 5.9.6 was released on Friday December 15th, 2017. It replaces skiboot-5.9.5 as the current stable release in the 5.9.x series.
Over skiboot-5.9.5, we have a few bug fixes, they are:
sensors: occ: Skip counter type of sensors
Don’t add counter type of sensors to device-tree as they don’t fit into hwmon sensor interface.
p9_stop_api updates to support IMC across deep stop states.
opal/xscom: Add recovery for lost core wakeup scom failures.
Due to a hardware issue where core responding to scom was delayed due to thread reconfiguration, leaves the SCOM logic in a state where the subsequent scom to that core can get errors. This is affected for Core PC scom registers in the range of 20010A80-20010ABF
The solution is if a xscom timeout occurs to one of Core PC scom registers in the range of 20010A80-20010ABF, a clearing scom write is done to 0x20010800 with data of ‘0x00000000’ which will also get a timeout but clears the scom logic errors. After the clearing write is done the original scom operation can be retried.
The scom timeout is reported as status 0x4 (Invalid address) in HMER[21-23].