How to find the hardware uptime for IBM Power Systems Frames

We needed to find the hardware uptime for a particular POWER9 frame to determine how close we were to hitting this known POWER9 firmware bug.

LPAR boot on POWER9 stops with CA000040

https://www.ibm.com/support/pages/node/6370613

We found we could calculate this by looking at the "Progress Indicator History" view in ASMI and looking at the date associated with RUNTIME/STANDBY and working out how many days had passed since the frame was powered up.

We also find this technote, which provides a small C program to calculate the "hardware platform uptime". Based on our tests (on AIX/VIOS) it works well.

AIX Example HW Platform uptime

https://www.ibm.com/support/pages/node/1078437