[PATCH v3 0/9] Add support for SCMIv4.0 Powercap Extensions

Philip Radford philip.radford at arm.com
Thu Feb 26 06:18:21 PST 2026


Hi all,

I will be taking over this series from Cristian and in doing so I have
addressed a couple of issues raised by the first version and added two
additional patches since Cristian's original series:

[6/9] exposes the measurement averaging interval (MAI) value when the
agent has registered to receive power measurement change notifications
for the power capping domain.

[9/9] adds MAI get and set support for the powercap protocol.

The original series was based on v6.17-rc1 whereas this version has been
based on v7.0-rc1.

The rest of Cristian's series is explained below;

SCMIv4.0 [1] introduces some new features and commands into the Powercap
protocol. In a nutshell, such protocol changes add support for:

 - setting multiple powercap limit/interval constraints for each SCMI
   powercap domain which supports multiple Concurrent Power Limit
 - enabling more Powercap commands to use Fastchannels mechanism
 - adding multiple constraints support to the existing notifications

After a bit of needed updates in the SCMI core this series adds:

- support for the idea of optional multiple Concurrent Power Limit (CPLs)
- support for the new FCs
- support for extended notifications
- enable usage of such multiple constraint in the ARM SCMI Powercap driver

Note that the public SCMIv4.0 spec at [1] is currently still BETA0, so
this series could anyway need some minor rework along the way and
definitely will need to wait for a final public release before being
possibly merged.

Tested in a mocked setup implementing the new protocol extensions.
Based on v7.0-rc1.

Thanks,
Phil
---
V2->V3
- Added powercap MAI get/set support
V1->V2
- Rebased on sudeep/for-next/scmi/updates
- Amended Copyright to include 2026
- Added patch to extend powercap report to include MAI
- Removed creation of pi powercap_info struct due to legacy code change
- Amended references to pi->version and similar, which were based on
  legacy code
- Wrapped two variables in le32_to_cpu() to appease Sparse warnings
- Amended comparing operator value in response to feedback

Cristian Marussi (7):
  firmware: arm_scmi: Add an optional custom parameter to fastchannel
    helpers
  firmware: arm_scmi: Refactor powercap domain layout
  firmware: arm_scmi: Add SCMIv4.0 Powercap basic support
  firmware: arm_scmi: Add SCMIv4.0 Powercap FCs support
  firmware: arm_scmi: Add SCMIV4.0 Powercap notifications support
  include: trace: Add new parameter to trace_scmi_fc_call
  powercap: arm_scmi: Enable multiple constraints support

Philip Radford (2):
  firmware: arm_scmi: Extend powercap report to include MAI
  firmware: arm_scmi: add Powercap MAI get/set support

 drivers/firmware/arm_scmi/driver.c    |  12 +-
 drivers/firmware/arm_scmi/perf.c      |  16 +-
 drivers/firmware/arm_scmi/powercap.c  | 976 ++++++++++++++++++++------
 drivers/firmware/arm_scmi/protocols.h |   2 +-
 drivers/powercap/arm_scmi_powercap.c  |  54 +-
 include/linux/scmi_protocol.h         |  87 ++-
 include/trace/events/scmi.h           |  12 +-
 7 files changed, 889 insertions(+), 270 deletions(-)

--
2.47.3




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