Commit cc89ff34 authored by Kajol Jain's avatar Kajol Jain Committed by Michael Ellerman
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docs: ABI: sysfs-bus-event_source-devices-hv_gpci: Document... 


docs: ABI: sysfs-bus-event_source-devices-hv_gpci: Document affinity_domain_via_virtual_processor sysfs interface file

Add details of the new hv-gpci interface file called
"affinity_domain_via_virtual_processor" in the ABI documentation.

Reviewed-by: default avatarAthira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: default avatarKajol Jain <kjain@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230729073455.7918-7-kjain@linux.ibm.com
parent 71a7ccb4

Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_gpci

+32 −0
Original line number Diff line number Diff line
@@ -144,3 +144,35 @@ Description: admin read only 
			   more information.



		* "-EFBIG" : System information exceeds PAGE_SIZE.



What:		/sys/devices/hv_gpci/interface/affinity_domain_via_virtual_processor

Date:		July 2023

Contact:	Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org>

Description:	admin read only

		This sysfs file exposes the system topology information by making HCALL

		H_GET_PERF_COUNTER_INFO. The HCALL is made with counter request value

		AFFINITY_DOMAIN_INFORMATION_BY_VIRTUAL_PROCESSOR(0xA0).



		* This sysfs file will be created only for power10 and above platforms.



		* User needs root privileges to read data from this sysfs file.



		* This sysfs file will be created, only when the HCALL returns "H_SUCCESS",

		  "H_AUTHORITY" or "H_PARAMETER" as the return type.



		  HCALL with return error type "H_AUTHORITY" can be resolved during

		  runtime by setting "Enable Performance Information Collection" option.



		* The end user reading this sysfs file must decode the content as per

		  underlying platform/firmware.



		Possible error codes while reading this sysfs file:



		* "-EPERM" : Partition is not permitted to retrieve performance information,

			    required to set "Enable Performance Information Collection" option.



		* "-EIO" : Can't retrieve system information because of invalid buffer length/invalid address

			   or because of some hardware error. Refer to getPerfCountInfo documentation for

			   more information.



		* "-EFBIG" : System information exceeds PAGE_SIZE.