[RFC PATCH 0/8] coresight: syscfg: dynamic load, resource management

Mike Leach mike.leach at linaro.org
Wed May 12 14:17:44 PDT 2021


This patchset represents the second phase of CoreSight configuration
management.

1) API updated to allow dynamic load and unload of configurations and
features. Dependency management between loaded sets is added.

2) New configuration and feature sets can be added using a loadable module.
An example in /samples/coresight is provided to demonstrate this.

3) Resource management API is added. This allows the system to ensure that
loaded configurations and features are only loaded onto devices that can
support them.

Further - it ensures that configurations with multiple features cannot over
allocate resources.

4) configfs can be used to activate a configuration which will then be used
when controlling tracing using sysfs.

5) Resource management is added to ETMv4 configurations. This allows current
and future features and configurations to be defined in terms of resources
used as well as registers to be programmed.

Defining features in this way allows the resource management to operate
correctly.

The perf event parsing is also adjusted to allow the ETM resources requested
on the command line (e.g. address filters, etc) to be correctly handled
using resoruce management alongside the complex configurations such as
autofdo.

Applies to coresight/next - which is 5.13-rc1 + initial Coresight configuration
patchset.

To follow in future revisions / sets:-
a) load of additional config and features by configfs
b) ECT and CTI and other Coresight components support for configuration and
features.


Mike Leach (8):
  coresight: syscfg: Update API to allow dynamic load and unload
  coresight: syscfg: Update load API for config loadable modules
  coresight: syscfg: Example CoreSight configuration loadable module
  coresight: configfs: Allow configfs to activate configuration.
  coresight: syscfg: Add API to check and validate device resources.
  coresight: etm4x: syscfg: Add resource management to etm4x.
  coresight: etm4x: Update perf event resource handling.
  coresight: etm4x: Update configuration example.

 MAINTAINERS                                   |   1 +
 .../hwtracing/coresight/coresight-cfg-afdo.c  |  38 +-
 .../coresight/coresight-cfg-preload.c         |   9 +-
 .../hwtracing/coresight/coresight-config.c    |  71 ++-
 .../hwtracing/coresight/coresight-config.h    |  45 +-
 .../hwtracing/coresight/coresight-etm4x-cfg.c | 533 ++++++++++++++++++
 .../hwtracing/coresight/coresight-etm4x-cfg.h | 196 ++++++-
 .../coresight/coresight-etm4x-core.c          | 250 +++-----
 .../coresight/coresight-syscfg-configfs.c     |  87 +++
 .../coresight/coresight-syscfg-configfs.h     |   4 +
 .../hwtracing/coresight/coresight-syscfg.c    | 390 +++++++++++--
 .../hwtracing/coresight/coresight-syscfg.h    |  38 +-
 include/linux/coresight.h                     |   2 +
 samples/Kconfig                               |   9 +
 samples/Makefile                              |   1 +
 samples/coresight/Makefile                    |   4 +
 samples/coresight/coresight-cfg-sample.c      |  73 +++
 17 files changed, 1511 insertions(+), 240 deletions(-)
 create mode 100644 samples/coresight/Makefile
 create mode 100644 samples/coresight/coresight-cfg-sample.c

-- 
2.17.1




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