From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933596AbaCQPih (ORCPT ); Mon, 17 Mar 2014 11:38:37 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:18445 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756604AbaCQPie (ORCPT ); Mon, 17 Mar 2014 11:38:34 -0400 X-AuditID: cbfee61a-b7fb26d00000724f-8d-532716f7ed31 Date: Mon, 17 Mar 2014 16:38:24 +0100 From: Lukasz Majewski To: Viresh Kumar , "Rafael J. Wysocki" Cc: Lukasz Majewski , "cpufreq@vger.kernel.org" , Linux PM list , Jonghwa Lee , Lukasz Majewski , linux-kernel , Bartlomiej Zolnierkiewicz , Myungjoo Ham , Tomasz Figa , Thomas Abraham , thomas.ab@samsung.com, "linux-arm-kernel@lists.infradead.org" , linux-samsung-soc@vger.kernel.org Subject: Re: [RFC v3 0/5] cpufreq:LAB: Support for LAB governor. Message-id: <20140317163824.3c5480b3@amdc2363> In-reply-to: <1393928852-22725-1-git-send-email-l.majewski@samsung.com> References: <1367590072-10496-1-git-send-email-jonghwa3.lee@samsung.com> <1393928852-22725-1-git-send-email-l.majewski@samsung.com> Organization: SPRC Poland X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.10; x86_64-pc-linux-gnu) MIME-version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprOIsWRmVeSWpSXmKPExsVy+t9jQd3vYurBBv1PrC02zljPavG06Qe7 RefZJ8wWbx5xW7x5uJnRYtPja6wWl3fNYbP43HuE0WLG+X1MFrcbV7BZnDl9idVi/YzXLBab J2xks+hYxmix8auHA7/Hzll32T3uXNvD5rF5Sb3HumlvmT22XG1n8ejbsorR4/MmuQD2KC6b lNSczLLUIn27BK6MS3tqCn6IV3xbs5itgfGWUBcjJ4eEgInEvKX32SBsMYkL99YD2VwcQgLT GSWWT97NCuH8YpTobLrKBFLFIqAq8e/JARYQm01AT+Lz3adgcRGBUImjU7+ygzQwC5xhkZhz dAJYkbCAg8SJXU3MIDYvUEProgOMIDangLvE8RXNzBAbWhklLu+8ATaJX0BSov3fD2aIm+wk zn3awA7RLCjxY/I9sKHMAloSm7c1sULY8hKb17xlnsAoOAtJ2SwkZbOQlC1gZF7FKJpakFxQ nJSea6hXnJhbXJqXrpecn7uJERxdz6R2MK5ssDjEKMDBqMTD+4JNPViINbGsuDL3EKMEB7OS CO8lXqAQb0piZVVqUX58UWlOavEhRmkOFiVx3gOt1oFCAumJJanZqakFqUUwWSYOTqkGxglK U6d8avv3vXtyhYbewfqHWd/jc3c/NHdlvjBN4a9xQ5umO7tx5ly5JXdY1q+ZXuquHcDYvLbJ cs3lVY1t3FyVFnOuvz80yTSwO2C2f5+pwLwUiwDW/fJvhO+d/fSr5IGm+Fq3p00Hf6+6sTtF WNL01OU2udgzPVMa+bdUe6ytVO7Pu1Aer8RSnJFoqMVcVJwIADgeVBCqAgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dear all, > Despite this patch set is working and applicable on top of 3.14-rc5, > please regard it solely as a pure RFC. > > This patch provides support for LAB governor build on top of ondemand. > Previous version of LAB can be found here: > http://thread.gmane.org/gmane.linux.kernel/1484746/match=cpufreq > > LAB short reminder: > > LAB uses information about how many cores are in "idle" state (the > core idleness is represented as the value between 0 and 100) and the > overall load of the system (from 0 to 100) to decide about frequency > to be set. It is extremely useful with SoCs like Exynos4412, which > can set only one frequency for all cores. > > Important design decisions: > > - Reuse well established ondemand governor's internal code. To do this > I had to expose some previously static internal ondemand code. > This allowed smaller LAB code when compared to previous version. > > - LAB works on top of ondemand, which means that one via device tree > attributes can specify if and when e.g. BOOST shall be enabled or > if any particular frequency shall be imposed. For situation NOT > important from the power consumption reduction viewpoint the ondemand > is used to set proper frequency. > > - It is only possible to either compile in or not the LAB into the > kernel. There is no "M" option for Kconfig. It is done on purpose, > since ondemand itself can be also compiled as a module and then it > would be possible to remove ondemand when LAB is working on top of it. > > - The LAB operation is specified (and thereof extendable) via device > tree lab-ctrl-freq attribute defined at /cpus/cpu0. > > > Problems: > - How the governor will work for big.LITTLE systems (especially > Global Task Scheduling). > - Will there be agreement to expose internal ondemand code to be > reused for more specialized governors. > > Test HW: > Exynos4412 - Trats2 board. > Above patches were posted on top of Linux 3.14-rc5 > (SHA1: 3f9590c281c66162bf8ae9b7b2d987f0a89043c6) > Any comments about those patches? > Lukasz Majewski (5): > cpufreq:LAB:ondemand Adjust ondemand to be able to reuse its methods > cpufreq:LAB:cpufreq_governor Adjust cpufreq_governor.[h|c] to > support LAB > cpufreq:LAB:lab Add LAB governor code > cpufreq:LAB:Kconfig Add LAB definitions to Kconfig > cpufreq:LAB:dts:trats2: Add DTS nodes for LAB governor > > arch/arm/boot/dts/exynos4412-trats2.dts | 29 ++ > drivers/cpufreq/Kconfig | 28 ++ > drivers/cpufreq/Makefile | 1 + > drivers/cpufreq/cpufreq_governor.c | 7 + > drivers/cpufreq/cpufreq_governor.h | 12 + > drivers/cpufreq/cpufreq_lab.c | 457 > +++++++++++++++++++++++++++++++ > drivers/cpufreq/cpufreq_ondemand.c | 24 +- 7 files changed, > 550 insertions(+), 8 deletions(-) create mode 100644 > drivers/cpufreq/cpufreq_lab.c > -- Best regards, Lukasz Majewski Samsung R&D Institute Poland (SRPOL) | Linux Platform Group