[PATCH v3 7/9] powerpc/pseries: Enable HVPIPE event message interrupt

[Tyrel Datwyler]

On 8/28/25 4:08 PM, Haren Myneni wrote:
> The hypervisor signals the OS via a Hypervisor Pipe Event external
> interrupt when data is available to be received from the pipe.
> Then the OS  should call RTAS check-exception and provide the input
> Event Mask as defined for the ‘ibm,hvpipe-msg-events’. In response,
> check-exception will return an event log containing an Pipe Events
> message. This message contains the source ID for which this
> message is intended to and the pipe status such as whether the
> payload is pending in the hypervisor or pipe to source is closed.
> 
> If there is any user space process waiting in the wait_queue for
> the payload from this source ID, wake up that process which can
> issue read() to obtain payload with ibm,receive-hvpipe-msg RTAS
> or close FD if the pipe to source is closed.
> 
> The hypervisor has one pipe per partition for all sources and it
> will not deliver another hvpipe event message until the partition
> reads the payload for the previous hvpipe event. So if the source
> ID is not found in the source list, issue the dummy
> ibm,receive-hvpipe-msg RTAS so that pipe will not blocked.
> 
> Register hvpipe event source interrupt based on entries from
> /proc/device-tree//event-sources/ibm,hvpipe-msg-events property.
> 
> Signed-off-by: Haren Myneni <haren at linux.ibm.com>
> Reviewed-by: Mahesh Salgaonkar <mahesh at linux.ibm.com>
> Tested-by: Shashank MS <shashank.gowda at in.ibm.com>
> ---

Reviewed-by: Tyrel Datwyler <tyreld at linux.ibm.com>