This driver implements support for on-chip Embedded Tracing Macrocell and
Embedded Trace Buffer. It allows to trigger tracing of kernel execution flow
and exporting trace output to userspace via character device and a sysrq
combo.

Trace output can then be decoded by a fairly simple open source tool [1]
which is already sufficient to get the idea of what the kernel is doing.

[1]: http://github.com/virtuoso/etm2humanSigned-off-by: NAlexander Shishkin <virtuoso@slind.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>