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efc219320f
Backport: manual fix in funnel_enable/disable because later patches have
been backported before it.
Since CoreSight hardware topology can use a 'hidden' funnel in the
trace data path, this kind funnel doesn't have register for accessing
and is used by default from hardware design perspective. Below is an
example for related hardware topology:
+------+ +------+
| cpu0 |->| ETM |-\
+------+ +------+ \-> +--------+ +-----+
...... | Funnel |->| ETF |-\ Hidden funnel
+------+ +------+ /-> +--------+ +-----+ \ |
| cpu3 |->| ETM |-/ \ V
+------+ +------+ \-> +--------+
| Funnel |-> ...
+------+ +------+ /-> +--------+
| cpu4 |->| ETM |-\ /
+------+ +------+ \-> +--------+ +-----+ /
...... | Funnel |->| ETF |-/
+------+ +------+ /-> +--------+ +-----+
| cpu7 |->| ETM |-/
+------+ +------+
The CoreSight funnel driver only supports dynamic funnel with
registration register resource, thus it cannot support for the static
funnel case and it's impossible to create trace data path for this case.
This patch is to extend CoreSight funnel driver to support both for
static funnel and dynamic funnel. For the dynamic funnel it reuses the
code existed in the driver, for static funnel the driver will support
device probe if without providing register resource and the driver skips
registers accessing when detect the register base is NULL.
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Wanglai Shi <shiwanglai@hisilicon.com>
Suggested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(Upstream commit 78e6427b4e).
Bug: 140266694
Change-Id: I9bb1b61d37d729dece8a5d3a66c5d1db1a3b5863
Signed-off-by: Yabin Cui <yabinc@google.com>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
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