3 Commits

Author	SHA1	Message	Date
Cristian Marussi	3e767d6850	powercap: arm_scmi: Remove recursion while parsing zones ... Powercap zones can be defined as arranged in a hierarchy of trees and when registering a zone with powercap_register_zone(), the kernel powercap subsystem expects this to happen starting from the root zones down to the leaves; on the other side, de-registration by powercap_deregister_zone() must begin from the leaf zones. Available SCMI powercap zones are retrieved dynamically from the platform at probe time and, while any defined hierarchy between the zones is described properly in the zones descriptor, the platform returns the availables zones with no particular well-defined order: as a consequence, the trees possibly composing the hierarchy of zones have to be somehow walked properly to register the retrieved zones from the root. Currently the ARM SCMI Powercap driver walks the zones using a recursive algorithm; this approach, even though correct and tested can lead to kernel stack overflow when processing a returned hierarchy of zones composed by particularly high trees. Avoid possible kernel stack overflow by substituting the recursive approach with an iterative one supported by a dynamically allocated stack-like data structure. Fixes: b55eef5226 ("powercap: arm_scmi: Add SCMI Powercap based driver") Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>	2023-07-20 20:27:10 +02:00
Cristian Marussi	aaffb4cacd	powercap: arm_scmi: Add support for disabling powercaps on a zone ... Add support to disable/enable powercapping on a zone. Acked-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20230531152039.2363181-4-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>	2023-06-06 14:05:10 +01:00
Cristian Marussi	b55eef5226	powercap: arm_scmi: Add SCMI Powercap based driver ... Add a powercap driver that, using the ARM SCMI Protocol to query the SCMI platform firmware for the list of existing Powercap domains, registers all of such discovered domains under the new 'arm-scmi' powercap control type. A new simple powercap zone and constraint is registered for all the SCMI powercap zones that are found. Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>	2022-10-25 18:53:15 +02:00