trace/coresight/coresight-config.rst

1 .. SPDX-License-Identifier: GPL-2.0
14 programming of the CoreSight system with pre-defined configurations that
17 Many CoreSight components can be programmed in complex ways - especially ETMs.
30 --------
41 accesses in the driver - the resource usage and parameter descriptions
43 and efficient for the feature to be programmed onto the device when required.
47 will be programmed into the device hardware.
56 feature being enabled that can adjust the behaviour of the operation programmed
59 For example, this could be a count value in a programmed operation that repeats
67 system - which is described below.
74 --------------
82 enabled on a class of devices - i.e. any ETMv4, or specific devices, e.g. a
118     perf record -e cs_etm/autofdo/ myapp
125    In this case 'strobing' is enabled & programmed into the ETMv4.
139 Mount configfs as normal and the 'cs-syscfg' subsystem will appear::
142     cs-syscfg  stp-policy
144 This has two sub-directories::
146     $ cd cs-syscfg/
220 The key directory here is 'events' - a generic perf directory which allows
234     $ perf record -e cs_etm/autofdo/u --per-thread <application>
238     $ perf record -e cs_etm/autofdo,preset=1/u --per-thread <application>
256 This will then use any default parameter values in the features - which can be
264 The valid values for preset are 0 - to deselect presets, and any value of
265 <n> where a preset<n> sub-directory is present.