summaryrefslogtreecommitdiff
path: root/drivers/devfreq/Makefile
AgeCommit message (Collapse)Author
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-06PM / devfreq: rockchip: add devfreq driver for rk3399 dmcLin Huang
base on dfi result, we do ddr frequency scaling, register dmc driver to devfreq framework, and use simple-ondemand policy. Signed-off-by: Lin Huang <hl@rock-chips.com> Signed-off-by: MyngJoo Ham <myngjoo.ham@samsung.com> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
2016-05-03PM / devfreq: exynos: Remove unused exynos4/5 busfreq driverChanwoo Choi
This patch removes the unused exynos4/5 busfreq driver. Instead, generic exynos-bus frequency driver support the all Exynos SoCs. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
2016-05-03PM / devfreq: Add new passive governorChanwoo Choi
This patch adds the new passive governor for DEVFREQ framework. The following governors are already present and used for DVFS (Dynamic Voltage and Frequency Scaling) drivers. The following governors are independently used for one device driver which don't give the influence to other device drviers and also don't receive the effect from other device drivers. - ondemand / performance / powersave / userspace The passive governor depends on operation of parent driver with specific governos extremely and is not able to decide the new frequency by oneself. According to the decided new frequency of parent driver with governor, the passive governor uses it to decide the appropriate frequency for own device driver. The passive governor must need the following information from device tree: - the source clock and OPP tables - the instance of parent device For exameple, there are one more devfreq device drivers which need to change their source clock according to their utilization on runtime. But, they share the same power line (e.g., regulator). So, specific device driver is operated as parent with ondemand governor and then the rest device driver with passive governor is influenced by parent device. Suggested-by: Myungjoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> [tjakobi: Reported RCU locking issue and cw00.choi fix it] Reported-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de> [linux.amoon: Reported possible recursive locking and cw00.choi fix it] Reported-by: Anand Moon <linux.amoon@gmail.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
2016-05-03PM / devfreq: exynos: Add generic exynos bus frequency driverChanwoo Choi
This patch adds the generic exynos bus frequency driver for AMBA AXI bus of sub-blocks in exynos SoC with DEVFREQ framework. The Samsung Exynos SoC have the common architecture for bus between DRAM and sub-blocks in SoC. This driver can support the generic bus frequency driver for Exynos SoCs. In devicetree, Each bus block has a bus clock, regulator, operation-point and devfreq-event devices which measure the utilization of each bus block. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> [m.reichl and linux.amoon: Tested it on exynos4412-odroidu3 board] Tested-by: Markus Reichl <m.reichl@fivetechno.de> Tested-by: Anand Moon <linux.amoon@gmail.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
2015-01-30devfreq: Fix build break of devfreq-event classChanwoo Choi
This patch fixes the build break of the exynos-ppmu driver because Makefile in drivers/devfreq don't include the entry of devfreq-event.c driver. The original patch[1] includes the entry to build devfreq-event.c without the build break. This build break is generated in the process of merging the patch. [1] https://lkml.org/lkml/2015/1/25/579 - [PATCH v10 1/7] devfreq: event: Add new devfreq_event class to provide basic data for devfreq governor CC init/version.o LD init/built-in.o drivers/built-in.o: In function `exynos_ppmu_probe': binder.c:(.text+0x4447ec): undefined reference to `devm_devfreq_event_add_edev' make: *** [vmlinux] Error 1 Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2015-01-30PM / devfreq: event: Add devfreq_event classChanwoo Choi
This patch adds a new class in devfreq, devfreq_event, which provides raw data (e.g., memory bus utilization, GPU utilization) for devfreq governors. - devfreq_event device : Provides raw data for a governor of a devfreq device - devfreq device : Monitors device state and changes frequency/voltage of the device using the raw data from its devfreq_event device. A devfreq device dertermines performance states (normally the frequency and the voltage vlues) based on the results its designtated devfreq governor: e.g., ondemand, performance, powersave. In order to give such results required by a devfreq device, the devfreq governor requires data that indicates the performance requirement given to the devfreq device. The conventional (previous) implementatino of devfreq subsystem requires a devfreq device driver to implement its own mechanism to acquire performance requirement for its governor. However, there had been issues with such requirements: 1. Although performance requirement of such devices is usually acquired from common devices (PMU/PPMU), we do not have any abstract structure to represent them properly. 2. Such performance requirement devices (PMU/PPMU) are actual hardware pieces that may be represented by Device Tree directly while devfreq device itself is a virtual entity that are not considered to be represented by Device Tree according to Device Tree folks. In order to address such issues, a devferq_event device (represented by this patch) provides a template for device drivers representing performance monitoring unit, which gives the basic or raw data for preformance requirement, which in turn, is required by devfreq governors. The following description explains the feature of two kind of devfreq class: - devfreq class (existing) : devfreq consumer device use raw data from devfreq_event device for determining proper current system state and change voltage/frequency dynamically using various governors. - devfreq_event class (new) : Provide measured raw data to devfreq device for governor Cc: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> [Commit message rewritten & conflict resolved by MyungJoo] Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2015-01-29PM / devfreq: tegra: add devfreq driver for Tegra Activity MonitorTomeu Vizoso
The ACTMON block can monitor several counters, providing averaging and firing interrupts based on watermarking configuration. This implementation monitors the MCALL and MCCPU counters to choose an appropriate frequency for the external memory clock. This patch is based on work by Alex Frid <afrid@nvidia.com> and Mikko Perttunen <mikko.perttunen@kapsi.fi>. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2013-06-03PM / devfreq: Add Exynos5-bus devfreq driver for Exynos5250Abhilash Kesavan
Exynos5-bus device devfreq driver monitors PPMU counters and adjusts operating frequencies and voltages with OPP. ASV should be used to provide appropriate voltages as per the speed group of the SoC rather than using a constant 1.025V. Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com> [myungjoo.ham@samsung.com: minor style update] Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Jonghwan Choi <jhbird.choi@samsung.com> Cc: Kukjin Kim <kgene.kim@samsung.com>
2013-06-03PM / devfreq: Move exynos4 devfreq driver into a new sub-directoryAbhilash Kesavan
In anticipation of the new exynos5 devfreq and ppmu driver, create an exynos sub-directory. Move the existing exynos4 devfreq driver into the same. Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Jonghwan Choi <jhbird.choi@samsung.com> Cc: Kukjin Kim <kgene.kim@samsung.com>
2011-12-20PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412.MyungJoo Ham
Exynos4-bus device devfreq driver add DVFS capability for Exynos4210/4212/4412-Bus (memory). The driver monitors PPMU counters of memory controllers and adjusts operating frequencies and voltages with OPP. For Exynos4210, vdd_int is controlled. For exynos4412/4212, vdd_mif and vdd_int are controlled. Dependency (CONFIG_EXYNOS_ASV): Exynos4 ASV driver has been posted in the mailing list; however, it si not yet upstreamed. Although the current revision of Exynos4 ASV patch does not contain "CONFIG_EXYNOS_ASV", we have added the symbol to hide the dependent from compilers for now. As soon as Exynos4 ASV drivers are merged, the #ifdef statement will be removed or the name will be changed. However, enabling ASV is essential in most Exynos4 chips to reduce the power consumption of Exynos4210 because without ASV, this Devfreq driver assumes the worst case scenario, which consumes more power. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> --- Changes from v1 - Support 4212 and 4412 as well as 4210.
2011-10-02PM / devfreq: Add basic governorsMyungJoo Ham
Four cpufreq-like governors are provided as examples. powersave: use the lowest frequency possible. The user (device) should set the polling_ms as 0 because polling is useless for this governor. performance: use the highest freqeuncy possible. The user (device) should set the polling_ms as 0 because polling is useless for this governor. userspace: use the user specified frequency stored at devfreq.user_set_freq. With sysfs support in the following patch, a user may set the value with the sysfs interface. simple_ondemand: simplified version of cpufreq's ondemand governor. When a user updates OPP entries (enable/disable/add), OPP framework automatically notifies devfreq to update operating frequency accordingly. Thus, devfreq users (device drivers) do not need to update devfreq manually with OPP entry updates or set polling_ms for powersave , performance, userspace, or any other "static" governors. Note that these are given only as basic examples for governors and any devices with devfreq may implement their own governors with the drivers and use them. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mike Turquette <mturquette@ti.com> Acked-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-02PM: Introduce devfreq: generic DVFS framework with device-specific OPPsMyungJoo Ham
With OPPs, a device may have multiple operable frequency and voltage sets. However, there can be multiple possible operable sets and a system will need to choose one from them. In order to reduce the power consumption (by reducing frequency and voltage) without affecting the performance too much, a Dynamic Voltage and Frequency Scaling (DVFS) scheme may be used. This patch introduces the DVFS capability to non-CPU devices with OPPs. DVFS is a techique whereby the frequency and supplied voltage of a device is adjusted on-the-fly. DVFS usually sets the frequency as low as possible with given conditions (such as QoS assurance) and adjusts voltage according to the chosen frequency in order to reduce power consumption and heat dissipation. The generic DVFS for devices, devfreq, may appear quite similar with /drivers/cpufreq. However, cpufreq does not allow to have multiple devices registered and is not suitable to have multiple heterogenous devices with different (but simple) governors. Normally, DVFS mechanism controls frequency based on the demand for the device, and then, chooses voltage based on the chosen frequency. devfreq also controls the frequency based on the governor's frequency recommendation and let OPP pick up the pair of frequency and voltage based on the recommended frequency. Then, the chosen OPP is passed to device driver's "target" callback. When PM QoS is going to be used with the devfreq device, the device driver should enable OPPs that are appropriate with the current PM QoS requests. In order to do so, the device driver may call opp_enable and opp_disable at the notifier callback of PM QoS so that PM QoS's update_target() call enables the appropriate OPPs. Note that at least one of OPPs should be enabled at any time; be careful when there is a transition. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mike Turquette <mturquette@ti.com> Acked-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>