kernel/linux.git/drivers/devfreq/Makefile, branch v6.6.132

PM / devfreq: mediatek: Introduce MediaTek CCI devfreq driver

2022-07-15T02:40:08+00:00

We introduce a devfreq driver for the MediaTek Cache Coherent Interconnect (CCI) used by some MediaTek SoCs. In this driver, we use the passive devfreq driver to get target frequencies and adjust voltages accordingly. In MT8183 and MT8186, the MediaTek CCI is supplied by the same regulators with the little core CPUs. Signed-off-by: Jia-Wei Chang Signed-off-by: Johnson Wang Acked-by: Chanwoo Choi Tested-by: Kevin Hilman Signed-off-by: Chanwoo Choi

PM / devfreq: Add a driver for the sun8i/sun50i MBUS

2021-12-10T06:56:07+00:00

This driver works by adjusting the divider on the DRAM controller's module clock. Thus there is no fixed set of OPPs, only "full speed" down to "quarter speed" (or whatever the maximum divider is on that variant). It makes use of the MDFS hardware in the MBUS, in "DFS" mode, which takes care of updating registers during the critical section while DRAM is inaccessible. This driver should support several sunxi SoCs, starting with the A33, which have a DesignWare DDR3 controller with merged PHY register space and the matching MBUS register layout (so not A63 or later). However, the driver has only been tested on the A64/H5, so those are the only compatibles enabled for now. Acked-by: Chanwoo Choi Signed-off-by: Samuel Holland Signed-off-by: Chanwoo Choi

PM / devfreq: tegra20: Deprecate in a favor of emc-stat based driver

2020-11-23T07:01:13+00:00

Remove tegra20-devfreq in order to replace it with a EMC_STAT based devfreq driver. Previously we were going to use MC_STAT based tegra20-devfreq driver because EMC_STAT wasn't working properly, but now that problem is resolved. This resolves complications imposed by the removed driver since it was depending on both EMC and MC drivers simultaneously. Acked-by: Chanwoo Choi Signed-off-by: Dmitry Osipenko Signed-off-by: Chanwoo Choi

PM / devfreq: Add generic imx bus scaling driver

2020-05-28T09:02:39+00:00

Add initial support for dynamic frequency switching on pieces of the imx interconnect fabric. All this driver does is set a clk rate based on an opp table, it does not map register areas. Signed-off-by: Leonard Crestez Tested-by: Martin Kepplinger Acked-by: Chanwoo Choi Signed-off-by: Chanwoo Choi

PM / devfreq: Add dynamic scaling for imx8m ddr controller

2019-12-30T00:59:05+00:00

Add driver for dynamic scaling the DDR Controller on imx8m chips. Actual frequency switching is implemented inside TF-A, this driver wraps the SMC calls and synchronizes the clk tree. The DRAM clocks on imx8m have the following structure (abridged): +----------+ |\ +------+ | dram_pll |-------|M| dram_core | | +----------+ |U|---------->| D | /--|X| | D | dram_alt_root | |/ | R | | | C | +---------+ | | |FIX DIV/4| | | +---------+ | | composite: | | | +----------+ | | | | dram_alt |----/ | | +----------+ | | | dram_apb |-------------------->| | +----------+ +------+ The dram_pll is used for higher rates and dram_alt is used for lower rates. The dram_alt and dram_apb clocks are "imx composite" and their parent can also be modified. This driver will prepare/enable the new parents ahead of switching (so that the expected roots are enabled) and afterwards it will call clk_set_parent to ensure the parents in clock framework are up-to-date. The driver relies on dram_pll dram_alt and dram_apb being marked with CLK_GET_RATE_NOCACHE for rate updates. Signed-off-by: Leonard Crestez Acked-by: Chanwoo Choi [cw00.choi: Edit the COMPILE_TEST module dependency in Kconfig] Signed-off-by: Chanwoo Choi

PM / devfreq: Introduce driver for NVIDIA Tegra20

2019-08-24T11:11:12+00:00

Add devfreq driver for NVIDIA Tegra20 SoC's. The driver periodically reads out Memory Controller counters and adjusts memory frequency based on the memory clients activity. Reviewed-by: Chanwoo Choi Signed-off-by: Dmitry Osipenko [Removed MAINTAINERS updates by MyungJoo so that it can be sent elsewhere.] Signed-off-by: MyungJoo Ham

PM / devfreq: tegra: Rename tegra-devfreq.c to tegra30-devfreq.c

2019-08-24T11:11:12+00:00

In order to reflect that driver serves NVIDIA Tegra30 and later SoC generations, let's rename the driver's source file to "tegra30-devfreq.c". This will make driver files to look more consistent after addition of a driver for Tegra20. Reviewed-by: Chanwoo Choi Signed-off-by: Dmitry Osipenko Signed-off-by: MyungJoo Ham

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

PM / devfreq: rockchip: add devfreq driver for rk3399 dmc

2016-09-06T04:26:34+00:00

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 Signed-off-by: MyngJoo Ham Reviewed-by: Chanwoo Choi

PM / devfreq: exynos: Remove unused exynos4/5 busfreq driver

2016-05-03T02:20:09+00:00

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 Signed-off-by: MyungJoo Ham Acked-by: Krzysztof Kozlowski