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 3911ECCA47A for ; Thu, 16 Jun 2022 12:51:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232152AbiFPMvE (ORCPT ); Thu, 16 Jun 2022 08:51:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56802 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229666AbiFPMvC (ORCPT ); Thu, 16 Jun 2022 08:51:02 -0400 Received: from mail-yw1-x1134.google.com (mail-yw1-x1134.google.com [IPv6:2607:f8b0:4864:20::1134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20B4A1DA5B for ; Thu, 16 Jun 2022 05:51:02 -0700 (PDT) Received: by mail-yw1-x1134.google.com with SMTP id 00721157ae682-30fdbe7467cso12979137b3.1 for ; Thu, 16 Jun 2022 05:51:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=vqcQdECaLEMeu798gUkn+FpUYyFy1DJMsUqQZAiS20E=; b=C4NbgkxvHPJh/aON7dBiPaprkR0AMp9bAaEZoqp2vri2dF8a738FS26t+ENTGKgqXv 271c7Q2E1es212I5u2fiRQ+Me0VjTprhPhG6+U+0nWZDNVkL5H+LUBq8+qxfHB9hpoAt 4cuvdcmf/FZL/Vkn/okI3dQ+v66vK32Y7ROAZcOu9qtkBVSfjE3mRF/OwRgU/7CaxFQG QZpStfNZjhkrXxSrBssNmFjAPFpBt7wRWfHDaP32lP5KU0Y7l1nvbKT1rChwUBXzi838 sp2fUvW2+7Xg3xKuaI81TQPaB4j9a555XhkVtv/rnk9CTbCh6MHZDyFsimq42v075hAF 7Org== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=vqcQdECaLEMeu798gUkn+FpUYyFy1DJMsUqQZAiS20E=; b=f2XIeczqY55nsNCMNgMwtcHsxZ01ganDsr6T6teW7Rd78Mnj6Rt4p7xDPHJH8ipQuc 7lPu9/JaTfWXBuSvOgFO7a4rD8De+0HRRTR1uFJQztDiLzuiDAsEZsgBZMYgvQx4TGy5 FcidEYkNnqxFJmHG3eKRWc+7NeKlFK62u/Grq7KFiEtOmpd6xpQSTG0gG7M/4xkzP9x0 s8dnyzXkPUe5d7rlIfl2FR6PqKxm2+lGXuNx7Z4VCxC/Cj/12xP+jAg7Pcm186yyjB9D TqDzWkRJ9W8cU4AtgAnngxBKbsiVmB2R6IIa9mfRXArsv6VRy3A0EUJsPJ1jjRUiUuoP z29Q== X-Gm-Message-State: AJIora8SbVlTwmjCbWEbokmAw/+8yDaDm1heFf9jMPpAkUmsfm6zPZ9k iaUs7tU85ws/s+ierf9jgwmxsWdPO7RVjhwsrwmLSg== X-Google-Smtp-Source: AGRyM1sEXuGD1MkxQDndknFUJmjARkkpTgwaVKIO0Ag/GmRSrXKMYSNgjpE6bf4U9IKfhpzp9x6XeHiOpAZohIdUHsQ= X-Received: by 2002:a0d:cc54:0:b0:317:752c:bcf3 with SMTP id o81-20020a0dcc54000000b00317752cbcf3mr1901735ywd.437.1655383861386; Thu, 16 Jun 2022 05:51:01 -0700 (PDT) MIME-Version: 1.0 References: <20220609150851.23084-1-max.oss.09@gmail.com> In-Reply-To: <20220609150851.23084-1-max.oss.09@gmail.com> From: Linus Walleij Date: Thu, 16 Jun 2022 14:50:49 +0200 Message-ID: Subject: Re: [PATCH v1 0/5] power: domain: Add driver for a PM domain provider which controls To: Max Krummenacher Cc: max.krummenacher@toradex.com, Ulf Hansson , linux-pm@vger.kernel.org, Francesco Dolcini , Mark Brown , "Rafael J . Wysocki" , Kevin Hilman , Andrejs Cainikovs , Biju Das , Bjorn Andersson , Catalin Marinas , Dmitry Baryshkov , Fabio Estevam , Geert Uytterhoeven , Krzysztof Kozlowski , Marcel Ziswiler , NXP Linux Team , Pengutronix Kernel Team , Rob Herring , Sascha Hauer , Shawn Guo , Vinod Koul , Will Deacon , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 9, 2022 at 5:10 PM Max Krummenacher wrote: > This series adds a PM domain provider driver which enables/disables > a regulator to control its power state. Actually, we did this on the U8500 in 2011. IIRC this led to problems because we had to invent "atomic regulators" because regulators use kernel abstractions that assume slowpath (process context) and power domains does not, i.e. they execute in fastpath, such as an interrupt handler. The atomic regulator was a subset of regulator that only handled regulators that would result in something like an atomic register write. In the end it was not worth trying to upstream this approach, and as I remember it, Ulf Hansson intended to let the power domains poke these registers directly, which was easier. (It's on Ulfs TODO list to actually implement this, hehe.) Yours, Linus Walleij 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 065B1C433EF for ; Thu, 16 Jun 2022 12:52:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=C4TGjJdahnYAQ2j47qN36Kmnf/P3ugSpIgF0AosnUP0=; b=gfLK/tjtajTcTW GJeksnwY7gtpkv0tEciXOkUBX2JWzQhfe5H2lcpTSXfYJfxO/G+LQPclIndf1CGjCiG2+CiIZ29wX PwhnTOM3UYCnQ3NZNyCQqZFhGQnoHRbZhIU0l1VykDVThex3EQWW1u07yV+6aKZ0uMdgNv+ZcnQp5 lxGpOw2xiQckbX5NpCQyaBQqDws/7ofQWyZemAO5AXwc/PYLNXGA3TJ3rQrntdywtZm0pq/jemfsG uR2FgbkwzNoEkenl+1ksde04yj5tPEk2YWgBttiTUQdsQ7lB2w1mdmewDlnrJTo32s62GC+rc3nF1 iesop/ZEWwOwm/XqWk+Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o1oxp-002LZj-J8; Thu, 16 Jun 2022 12:51:09 +0000 Received: from mail-yw1-x1136.google.com ([2607:f8b0:4864:20::1136]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1o1oxj-002LXW-8o for linux-arm-kernel@lists.infradead.org; Thu, 16 Jun 2022 12:51:07 +0000 Received: by mail-yw1-x1136.google.com with SMTP id 00721157ae682-2ef5380669cso12727447b3.9 for ; Thu, 16 Jun 2022 05:51:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=vqcQdECaLEMeu798gUkn+FpUYyFy1DJMsUqQZAiS20E=; b=C4NbgkxvHPJh/aON7dBiPaprkR0AMp9bAaEZoqp2vri2dF8a738FS26t+ENTGKgqXv 271c7Q2E1es212I5u2fiRQ+Me0VjTprhPhG6+U+0nWZDNVkL5H+LUBq8+qxfHB9hpoAt 4cuvdcmf/FZL/Vkn/okI3dQ+v66vK32Y7ROAZcOu9qtkBVSfjE3mRF/OwRgU/7CaxFQG QZpStfNZjhkrXxSrBssNmFjAPFpBt7wRWfHDaP32lP5KU0Y7l1nvbKT1rChwUBXzi838 sp2fUvW2+7Xg3xKuaI81TQPaB4j9a555XhkVtv/rnk9CTbCh6MHZDyFsimq42v075hAF 7Org== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=vqcQdECaLEMeu798gUkn+FpUYyFy1DJMsUqQZAiS20E=; b=VoxyeIMgkXJnogXrrzqKWlIHx/hl/+1JsrJzqGyhTBWbVsPnnsGqrdtclEpD4kfQlw xbvpzVKmNojxlAOj/ndcCwR2X9LfoKJGn49HIqXdXD4mF5oLZaGN6V7T/1P4jcB5Zzwp eLFIP55Iq1n6X0/3BbIP2ka718iRpmskRyZJlEAGDR65JftebPOHyuraLco+4NwzSCqS 1sS9emnE44dT0qYs9p7DvsVDkKiD/HLpqUPOjmVJ4amMJXdt1qHYifCmWKQCaXmji4ah Iy7CDbbJCs86B324GmUr7OyZMK08rnaOoRczbsgU3q7a1PAFN2dVVjLAf9zKG/oTUi9d dF2A== X-Gm-Message-State: AJIora/UcammeHRLYdnyVOv+HaZH+pMOhVc0QI+rQ5+XnjkKcKSIPZSN Yt0+wiGQgZcoq8Exo2vFnFESX4y8k6L1K5IeXRivqw== X-Google-Smtp-Source: AGRyM1sEXuGD1MkxQDndknFUJmjARkkpTgwaVKIO0Ag/GmRSrXKMYSNgjpE6bf4U9IKfhpzp9x6XeHiOpAZohIdUHsQ= X-Received: by 2002:a0d:cc54:0:b0:317:752c:bcf3 with SMTP id o81-20020a0dcc54000000b00317752cbcf3mr1901735ywd.437.1655383861386; Thu, 16 Jun 2022 05:51:01 -0700 (PDT) MIME-Version: 1.0 References: <20220609150851.23084-1-max.oss.09@gmail.com> In-Reply-To: <20220609150851.23084-1-max.oss.09@gmail.com> From: Linus Walleij Date: Thu, 16 Jun 2022 14:50:49 +0200 Message-ID: Subject: Re: [PATCH v1 0/5] power: domain: Add driver for a PM domain provider which controls To: Max Krummenacher Cc: max.krummenacher@toradex.com, Ulf Hansson , linux-pm@vger.kernel.org, Francesco Dolcini , Mark Brown , "Rafael J . Wysocki" , Kevin Hilman , Andrejs Cainikovs , Biju Das , Bjorn Andersson , Catalin Marinas , Dmitry Baryshkov , Fabio Estevam , Geert Uytterhoeven , Krzysztof Kozlowski , Marcel Ziswiler , NXP Linux Team , Pengutronix Kernel Team , Rob Herring , Sascha Hauer , Shawn Guo , Vinod Koul , Will Deacon , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220616_055103_363329_A39574D5 X-CRM114-Status: GOOD ( 12.30 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Jun 9, 2022 at 5:10 PM Max Krummenacher wrote: > This series adds a PM domain provider driver which enables/disables > a regulator to control its power state. Actually, we did this on the U8500 in 2011. IIRC this led to problems because we had to invent "atomic regulators" because regulators use kernel abstractions that assume slowpath (process context) and power domains does not, i.e. they execute in fastpath, such as an interrupt handler. The atomic regulator was a subset of regulator that only handled regulators that would result in something like an atomic register write. In the end it was not worth trying to upstream this approach, and as I remember it, Ulf Hansson intended to let the power domains poke these registers directly, which was easier. (It's on Ulfs TODO list to actually implement this, hehe.) Yours, Linus Walleij _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel