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Based on kernel version 3.16. Page generated on 2014-08-06 21:35 EST.

1	What:		/sys/firmware/opal/elog
2	Date:		Feb 2014
3	Contact:	Stewart Smith <stewart@linux.vnet.ibm.com>
4	Description:
5			This directory exposes error log entries retrieved
6			through the OPAL firmware interface.
7	
8			Each error log is identified by a unique ID and will
9			exist until explicitly acknowledged to firmware.
10	
11			Each log entry has a directory in /sys/firmware/opal/elog.
12	
13			Log entries may be purged by the service processor
14			before retrieved by firmware or retrieved/acknowledged by
15			Linux if there is no room for more log entries.
16	
17			In the event that Linux has retrieved the log entries
18			but not explicitly acknowledged them to firmware and
19			the service processor needs more room for log entries,
20			the only remaining copy of a log message may be in
21			Linux.
22	
23			Typically, a user space daemon will monitor for new
24			entries, read them out and acknowledge them.
25	
26			The service processor may be able to store more log
27			entries than firmware can, so after you acknowledge
28			an event from Linux you may instantly get another one
29			from the queue that was generated some time in the past.
30	
31			The raw log format is a binary format. We currently
32			do not parse this at all in kernel, leaving it up to
33			user space to solve the problem. In future, we may
34			do more parsing in kernel and add more files to make
35			it easier for simple user space processes to extract
36			more information.
37	
38			For each log entry (directory), there are the following
39			files:
40	
41			id:		An ASCII representation of the ID of the
42					error log, in hex - e.g. "0x01".
43	
44			type:		An ASCII representation of the type id and
45					description of the type of error log.
46					Currently just "0x00 PEL" - platform error log.
47					In the future there may be additional types.
48	
49			raw:		A read-only binary file that can be read
50					to get the raw log entry. These are
51					<16kb, often just hundreds of bytes and
52					"average" 2kb.
53	
54			acknowledge:	Writing 'ack' to this file will acknowledge
55					the error log to firmware (and in turn
56					the service processor, if applicable).
57					Shortly after acknowledging it, the log
58					entry will be removed from sysfs.
59					Reading this file will list the supported
60					operations (curently just acknowledge)
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