From mboxrd@z Thu Jan 1 00:00:00 1970 From: punit.agrawal@arm.com (Punit Agrawal) Date: Wed, 14 Nov 2012 14:58:21 +0000 Subject: Decoding the PTM traces In-Reply-To: References: Message-ID: <50A3B18D.60907@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Arun, You can think of the trace in the ETB as the raw stream resulting from the multiplexing of different trace streams. So to get to the PTM trace you'll first have to de-multiplex the stream, and then decode the stream based on the source - in this case PTM. The format of the data stored in the ETB is described in the ETM TRM Section 9.6 (http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0314h/Bgbhhidd.html). The decoding should give you a trace stream for each active trace source. The ATBID can be used to de-multiplex multiple sources, e.g., the two PTMs associated with the two A9s. The PTM stream can then be decoded using the Program Flow Trace Protocol described in Program Flow Trace Architecture Specification Section 4 (http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ihi0035b/Chddbbdf.html). Out of curiosity, may I ask what are you trying to do? Hope this helps. Feel free to ask for clarification. Cheers, Punit On 14/11/12 14:04, Arun KS wrote: > Hello, > > I m trying to capture and decode PTM trace from Cortex A9 dual core. > > I m successful in configuring the driver(arch/arm/kernel/etm.c) and > setting the funnel to get data in ETB. > But I don't know how to decode these traces. > > Anyone has any pointers? > > Thanks, > Arun > > _______________________________________________ > linaro-dev mailing list > linaro-dev at lists.linaro.org > http://lists.linaro.org/mailman/listinfo/linaro-dev > > > -- IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.