diff mbox series

[v4,06/10] docs: ABI: sysfs-bus-event_source-devices-hv_gpci: Document affinity_domain_via_virtual_processor sysfs interface file

Message ID 20230729073455.7918-7-kjain@linux.ibm.com (mailing list archive)
State Accepted
Commit cc89ff3491b61cebc90b3394eb6b36635173d0dd
Headers show
Series Add sysfs interface files to hv_gpci device to expose system information | expand

Commit Message

Kajol Jain July 29, 2023, 7:34 a.m. UTC 
Add details of the new hv-gpci interface file called
"affinity_domain_via_virtual_processor" in the ABI documentation.

Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
---
 .../sysfs-bus-event_source-devices-hv_gpci    | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_gpci b/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_gpci
index 9e81de18142f..5ee33218be83 100644
--- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_gpci
+++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_gpci
@@ -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.