libcoresightomap4430 is a set of libraries and examples of code to use STM and ETB hardware tracing modules on a OMAP4430 system on chip (for instance, on a Pandaboard).
There is no need for any driver. This code is made for the Texas Instruments version of STM (System Trace Module), not the ARM one; and the Embedded Trace Buffer (ETB). It provides user-space libraries, but you can modify it to make kernel modules.
Simply run make to compile all files, it will produce the stmwrite,
etbread and stpdecode binaries (among others).
Then send data to a STM channel:
# echo "tracing myevent #1" | ./stmwrite -c 10
# sleep 1
# echo "tracing myevent #2" | ./stmwrite -c 11
You can either export trace data off-chip via a JTAG interface, or fetch it from the ETB hardware buffer:
# ./etbread > mytrace
Finally, decode the trace:
# ./stpdecode mytrace
[12.01793921] [10] tracing myevent #1
[13.34567810] [11] tracing myevent #2
You can also use the libraries separately from using in your own program.
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libomap4430
Used to enable the EMU clock on the Pandaboard. This clock is needed to use some debug facilities such as STM.
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libstm
Used to send messages through the STM.
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libetb
Used to read messages from the ETB buffer.
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libstp
Used to decode messages read from the ETB. The messages are encoded according to the System Trace Protocol (STP) version 1 format. Since there is no public documentation for STP, the decoding might not work well.
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stmwrite
Program to write data to the STM.
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etbread
Program to read messages collected in the ETB.
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stpdecode
Program to decode a STP-formatted file (extracted with etbread, for instance).
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etbdecode
Reads from the ETB and decode the STP stream at the same time.