POWER9 Changes to OPAL API¶
This document is a summary of POWER9 changes to the OPAL API over what it was for POWER7 and POWER8. As the POWER series of processors (at least up to POWER9) require changes in the hypervisor to work on a new processor generation, this gives us an opportunity with POWER9 to clean up several parts of the OPAL API.
Eventually, when the kernel drops support for POWER8 and before, we can then remove the associated kernel code too.
Can now be extended beyond HILE BE/LE bits. If invalid flags are set on POWER9, OPAL_UNSUPPORTED will be returned.
/ibm,opal/compatible property now just lists
ibm,opal-v3and no longer
ibm,opal-v2(power9 and above only)
stdout-pathproperty from POWER9 and above as usage of
Add interrupt-parent property for
/ibm,opal/ipminode on POWER9 and above to make use of OPAL irqchip rather than event interface in linux.
Things we still have to do for POWER9:
PCI to use async API rather than returning delays
deprecate/remove v1 APIs where there’s a V2
Fix this FWTS warning:
FAILED [MEDIUM] DeviceTreeBaseDTCWarnings: Test 3, dtc reports warnings from device tree: Warning (reg_format): "reg" property in /ibm,opal/flash@0 has invalid length (8 bytes) (#address-cells == 0, #size-cells == 0)
Remove mi-version / ml-version from
/ibm,opal/firmwareand replace with something better and more portable