From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 569C0CA0FE8 for ; Fri, 1 Sep 2023 08:41:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240245AbjIAIlL (ORCPT ); Fri, 1 Sep 2023 04:41:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43570 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234306AbjIAIlK (ORCPT ); Fri, 1 Sep 2023 04:41:10 -0400 Received: from mailout2.w1.samsung.com (mailout2.w1.samsung.com [210.118.77.12]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0751D10CA for ; Fri, 1 Sep 2023 01:41:04 -0700 (PDT) Received: from eucas1p1.samsung.com (unknown [182.198.249.206]) by mailout2.w1.samsung.com (KnoxPortal) with ESMTP id 20230901084101euoutp021992c0b56291186fcd60e67d5feb5cbe~Aubh398_q0130701307euoutp02W for ; Fri, 1 Sep 2023 08:41:01 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20230901084101euoutp021992c0b56291186fcd60e67d5feb5cbe~Aubh398_q0130701307euoutp02W DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1693557661; bh=CGfcHhAknNmRLRtPsz9TJ84qeZVwd/lWgrb2qjzXDUA=; h=Date:Subject:To:Cc:From:In-Reply-To:References:From; b=h3PLZqSk1FZjWyqnBQZ+fOGFgpNvmOvefhqRibwsf3/mNIm0q+6+qNVS2eBIiQ7nX 7CYkxA7217X7Zgmowy7onwPXWaxJnYZU75U7TdPkg06GXAj6fb5khLJ1A8lwY6H5V8 SzDYxnKzXEsYpvBb9Cro2fmop/lwSfdz3Qc4K5YA= Received: from eusmges1new.samsung.com (unknown [203.254.199.242]) by eucas1p2.samsung.com (KnoxPortal) with ESMTP id 20230901084101eucas1p28d9fe4bd0bfc538ff17143f2f82973f5~AubhVgbcR1920219202eucas1p23; Fri, 1 Sep 2023 08:41:01 +0000 (GMT) Received: from eucas1p2.samsung.com ( [182.198.249.207]) by eusmges1new.samsung.com (EUCPMTA) with SMTP id 38.68.42423.D93A1F46; Fri, 1 Sep 2023 09:41:01 +0100 (BST) Received: from eusmtrp1.samsung.com (unknown [182.198.249.138]) by eucas1p2.samsung.com (KnoxPortal) with ESMTPA id 20230901084100eucas1p294e4cb447d47c67f8be4387702b07dc0~Aubg68mPS1944719447eucas1p2E; Fri, 1 Sep 2023 08:41:00 +0000 (GMT) Received: from eusmgms2.samsung.com (unknown [182.198.249.180]) by eusmtrp1.samsung.com (KnoxPortal) with ESMTP id 20230901084100eusmtrp1a277e2397ac5a4ecdedd98eb6e4d8c87~Aubg6OM7r2289322893eusmtrp1U; Fri, 1 Sep 2023 08:41:00 +0000 (GMT) X-AuditID: cbfec7f2-a51ff7000002a5b7-35-64f1a39d17ea Received: from eusmtip1.samsung.com ( [203.254.199.221]) by eusmgms2.samsung.com (EUCPMTA) with SMTP id 05.6D.14344.C93A1F46; Fri, 1 Sep 2023 09:41:00 +0100 (BST) Received: from [106.210.134.192] (unknown [106.210.134.192]) by eusmtip1.samsung.com (KnoxPortal) with ESMTPA id 20230901084059eusmtip1ef23d736e24bafeb4760f3a7876badb8~Aubf_4Cj02170521705eusmtip1Q; Fri, 1 Sep 2023 08:40:59 +0000 (GMT) Message-ID: Date: Fri, 1 Sep 2023 10:40:59 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.14.0 Subject: Re: [PATCH 04/11] thermal: exynos: remove fine-grained clk management Content-Language: en-US To: Krzysztof Kozlowski , Mateusz Majewski , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alim Akhtar , Bartlomiej Zolnierkiewicz , "Rafael J. Wysocki" , Daniel Lezcano , Amit Kucheria , Zhang Rui , Liam Girdwood , Mark Brown From: Marek Szyprowski In-Reply-To: Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrHKsWRmVeSWpSXmKPExsWy7djP87pzF39MMWhdyWXxYN42NovD8yss pj58wmbxfct1Jos1e88xWcz7LGsx/8g5Vou+Fw+ZLfa+3spu8e1KB5PFpsfXWC0u75rDZvG5 9wijxYzz+5gsJh6bzGwx98tUZovWvUfYLZ487GNzEPLYOesuu8fiPS+ZPDat6mTzuHNtD5vH 5iX1Hn1bVjF6fN4kF8AexWWTkpqTWZZapG+XwJWxcNdG9oJHXBVzm44xNjA+5uhi5OSQEDCR uH50K3sXIxeHkMAKRolNZ6+zQDhfGCW2Pb7FBOF8ZpS423WFEaZl1r1djBCJ5YwSc55/Y4Nw PjJKzDyyjA2kilfATuLAwmdgNouAisSaCTtZIOKCEidnPgGzRQVSJZ7dmsMOYgsLBEjcuzUL bAOzgLjErSfzmUBsEYF2Jonb1zlAFjALHGKW+LQRYhCbgKFE19susAWcQMsW/PrODNEsL7H9 7RxmkAYJge2cEtdmTmOBuNtF4tSvJ8wQtrDEq+Nb2CFsGYnTk3tYIBraGSUW/L7PBOFMYJRo eH4L6mtriTvnfgGt4wBaoSmxfpc+RNhR4k7zY1aQsIQAn8SNt4IQR/BJTNo2nRkizCvR0SYE Ua0mMev4Ori1By9cYp7AqDQLKVxmIfl/FpJ3ZiHsXcDIsopRPLW0ODc9tdgwL7Vcrzgxt7g0 L10vOT93EyMwCZ7+d/zTDsa5rz7qHWJk4mA8xCjBwawkwhtr9i5FiDclsbIqtSg/vqg0J7X4 EKM0B4uSOK+27clkIYH0xJLU7NTUgtQimCwTB6dUA1Ndq9jzt8/3/pN8oDPF3XeFsvaeLMkr 837LxwTYNe7abKVY53f0VtDp/l9J9evWhzS0W9nt2Ffb+GRyydl/74siWpu4jBb0tzgmFByp eVR8Y9+cHwcrN7Our7ydPG3d59nFv/grXf6e3vH39dSbByfsVesWvK62U9tp2pQN9yfMNTyg 9yr5lGPAH2Onq1NzTkw4Y5nRwKvN8K00SG+B+SfPevlKX/HYBhvHL+x/+3xDu9bZHU3pOr71 bM2O5P4pyZ7bO26GB1Z85jj73JUpoJnjcMXRabMiC7b+DH+4UrnKcY/TSa8WjSWXem+E/vIw +//kxdUT/zQPXl1f/LWLz8ria+utFW8D5i9cHWTf9O+MEktxRqKhFnNRcSIAlpoClfEDAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrAIsWRmVeSWpSXmKPExsVy+t/xu7pzFn9MMfgwS8PiwbxtbBaH51dY TH34hM3i+5brTBZr9p5jspj3WdZi/pFzrBZ9Lx4yW+x9vZXd4tuVDiaLTY+vsVpc3jWHzeJz 7xFGixnn9zFZTDw2mdli7pepzBate4+wWzx52MfmIOSxc9Zddo/Fe14yeWxa1cnmcefaHjaP zUvqPfq2rGL0+LxJLoA9Ss+mKL+0JFUhI7+4xFYp2tDCSM/Q0kLPyMRSz9DYPNbKyFRJ384m JTUnsyy1SN8uQS9j4a6N7AWPuCrmNh1jbGB8zNHFyMkhIWAiMeveLkYQW0hgKaPEmv+OEHEZ iZPTGlghbGGJP9e62LoYuYBq3jNKTD6zDSzBK2AncWDhMzYQm0VARWLNhJ0sEHFBiZMzn4DZ ogKpEt9v7QOrERbwkzi98j7YMmYBcYlbT+YzgQwVEWhnkji8/wqYwyxwhFni+MsjjBDrfjJK NLyaxwzSwiZgKNH1tgtsFCfQ6gW/vjNDjDKT6NraBTVWXmL72znMExiFZiG5ZBaSjbOQtMxC 0rKAkWUVo0hqaXFuem6xkV5xYm5xaV66XnJ+7iZGYNRvO/Zzyw7Gla8+6h1iZOJgPMQowcGs JMIba/YuRYg3JbGyKrUoP76oNCe1+BCjKTA4JjJLiSbnA9NOXkm8oZmBqaGJmaWBqaWZsZI4 r2dBR6KQQHpiSWp2ampBahFMHxMHp1QDkx3ruk/+F/0WSyZ8P8xx+MBW5itRyaEM5lNUOLN6 7A6/1r3dqVL/m8nWI5XBVyOzqP7c4kfin89IvEk/JfOqxPmTBEM8zx9t9rpHu4p3NKutTfm2 ZdnhO9zbcvymTHglsefRiWf7v8Q5f3hx8lOKx4cLAZsOZ30LnSGxM/Taq+2TI9+y8oe9l27h YP8n9O9C42R+3XV7l97g4XxRfkJQN+Mj233tev8ZqZlSKnuSZ9Y90flwqTnMM+tf+X6uB0yH l319FfpUcIbDao6f8QfCFmxt4nBt4k5uUMm3zdufaSKWGf4nqbzHvpQh/unn3mP55kpdjr+c Fq31FpgwK3ZXPffN+Vpm10v4F953WbTMRImlOCPRUIu5qDgRALBmaHuDAwAA X-CMS-MailID: 20230901084100eucas1p294e4cb447d47c67f8be4387702b07dc0 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-RootMTR: 20230829092412eucas1p2b79a6f90b9077a3a5486845b7e68bbc6 X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20230829092412eucas1p2b79a6f90b9077a3a5486845b7e68bbc6 References: <20230829091853.626011-1-m.majewski2@samsung.com> <20230829091853.626011-5-m.majewski2@samsung.com> Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org On 29.08.2023 11:56, Krzysztof Kozlowski wrote: > On 29/08/2023 11:18, Mateusz Majewski wrote: >> This clock only controls the register operations. The gain in power >> efficiency is therefore quite dubious, while there is price of added >> complexity that is important to get right (as a register operation might >> outright hang the CPU if the clock is not enabled). > So once it is done right, this stops being argument. The benefit is to > keep this clock disabled most of the time, which now we lost. > > I don't find this patch correct approach. I've suggested this change while playing with this driver. For me turning AHB clock on/off during normal driver operation seems to be over-engineering and really gives no real power saving benefits, especially if thermal driver is the only one that does such fine-grained clock management (none of the Exynos supported in mainline does that). Removing it simplifies code and makes it easier to understand or read, as the current code already was somehow problematic to understand and unintuitive: https://lore.kernel.org/all/c3258cb2-9a56-d048-5738-1132331a157d@linaro.org/ Taking into account that the driver is not really maintained, making it simpler without noticeable feature loss counts as a benefit for me. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland