From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Luba Subject: [PATCH v3] devfreq_cooling: let the driver supply the real power every time we need it Date: Tue, 14 Mar 2017 13:06:13 +0000 Message-ID: <20170314130616.7711-1-lukasz.luba@arm.com> Return-path: Received: from foss.arm.com ([217.140.101.70]:32778 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751113AbdCNNGs (ORCPT ); Tue, 14 Mar 2017 09:06:48 -0400 Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: linux-pm@vger.kernel.org Cc: chris.diamand@arm.com, lukasz.luba@arm.com, javi.merino@kernel.org, rui.zhang@intel.com, edubezval@gmail.com Hi, This patchset introduces a new interface for devfreq cooling in thermal framework. The previous version of the patch can be seen here [1]. I have simplified the implementation and introduced resource utilization scaling factor. The current implementation in the thermal devfreq cooling subsystem uses pre-calculated power table for each device to make a decision about allowed running state. When the driver registers itself to the thermal devfreq cooling subsystem, the framework creates the power table. The power table is then used by the thermal subsystem to keep the device in the thermal envelope. In the previous implementation the pre-calculated device's power table was scaled by current 'utilization' ('busy_time' and 'total_time' taken from devfreq 'last_status'). This idea meets the expectations of the devices which know better the actual power that they consume (thanks to power counters). When some parts/features of the device are not used the power value might be lower, while the frequency and utilization are the same. The proposed implementation provides possibility to register a driver to thermal devfreq cooling subsystem and use the driver's code during the calculation of the power in runtime. The device driver can still use pre-calculated power table when these new functions are not provided (the new extension can co-exist with old implementation). The first patch contains some refactoring for getting the voltage, the second implements the new feature, the third one changes trace function. Patchset is based on v4.11-rc2. Changes v3: - use new OPP interface (no need to lock rcu) v2 [2]: - removed 'flags' and power2state function, - split into a few patches, - simplified the logic of the new interface, - added resource utilization scaling factor, v1 [1]: - basic implementation Best Regards, Lukasz Luba [1] https://marc.info/?l=linux-pm&m=147395070729989&w=2 [2] http://marc.info/?l=linux-pm&m=148587920122854&w=2 Lukasz Luba (3): thermal: devfreq_cooling: refactor code and add get_voltage function thermal: devfreq_cooling: add new interface for direct power read trace: thermal: add another parameter *power to the tracing function drivers/thermal/devfreq_cooling.c | 117 ++++++++++++++++++++++++++++---------- include/linux/devfreq_cooling.h | 17 ++++++ include/trace/events/thermal.h | 11 ++-- 3 files changed, 110 insertions(+), 35 deletions(-) -- 2.9.2