From patchwork Thu Feb 6 15:11:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 11368711 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6FA9A109A for ; Thu, 6 Feb 2020 15:11:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E06E217BA for ; Thu, 6 Feb 2020 15:11:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581001912; bh=GXfnyk+5mxcLxh7DS10kpV2zW4ajtTvIlfSvgF1m6HE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kta6aP9SuuwJyJgGhcGiSdDyeG5JPjclIPogQ+86voLdIMa5wpCNCqfumN5anDy3n hNoClVawOK6c+960JyB1+C7270VoavrXpkXdxvkHED5SXQW4Bhl7smTd8RXw9P523E avlqBYxoYmRhNZcmeNb4eoYukF56LSCy1lAlsJqg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727560AbgBFPLn (ORCPT ); Thu, 6 Feb 2020 10:11:43 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:37532 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727398AbgBFPLm (ORCPT ); Thu, 6 Feb 2020 10:11:42 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc: To:From:Reply-To:Content-ID:Content-Description; bh=bJnoUKgVIb6mtplglvS+byAU4SeZA8CY+LwJLXnSv9Q=; b=d4FOvoR9mB6MjJZx9PSZuP7cMs 8Lk51gnZiYVTlTMhF4EsGFD6ToJ60uQM4F1z/tfidYrtd2Z/d3Vx1/tAepsJS+vX2Vw5bvtQvSWfQ ITfIfsrOEY8H2nNNRxEZDdHdOO7oj/3nnHnagHEO00aPO9n8HaloG3GVtAQ4new1L8StvMrPtqCuf AELbxsHSqcEJMEB0sfJ9tE13gQIfWXMGH9eD02llxz7qLW4xZElg8JIvwpWyCTuaSDaQfHRDMMhH9 VuN5tgp9ETqldP3c5p8VhzSkHgX7KwccuTklXw9xyz17FIEYmDivSlD4WDzJseFR+HhumxXQ+bsXV AuF0dzug==; Received: from [179.95.15.160] (helo=bombadil.infradead.org) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1izioc-000432-UC; Thu, 06 Feb 2020 15:11:42 +0000 Received: from mchehab by bombadil.infradead.org with local (Exim 4.92.3) (envelope-from ) id 1izioV-002oMm-N9; Thu, 06 Feb 2020 16:11:31 +0100 From: Mauro Carvalho Chehab To: Linux Media Mailing List Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , Amit Daniel Kachhap , Daniel Lezcano , Viresh Kumar , Javi Merino , Jonathan Corbet , linux-pm@vger.kernel.org, linux-doc@vger.kernel.org Subject: [PATCH 01/11] docs: thermal: convert cpu-idle-cooling.rst to ReST Date: Thu, 6 Feb 2020 16:11:20 +0100 Message-Id: <67d691731dc980b0dc9f599c8b6d031bdaba122d.1581001737.git.mchehab+huawei@kernel.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: References: MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Despite being named with .rst extension, this file doesn't match the ReST standard. It actually causes a crash at Sphinx: Sphinx parallel build error: docutils.utils.SystemMessage: /devel/v4l/docs/Documentation/driver-api/thermal/cpu-idle-cooling.rst:69: (SEVERE/4) Unexpected section title. Add needed markups for it to be properly parsed. While here, add it to the thermal index.rst. Signed-off-by: Mauro Carvalho Chehab --- .../driver-api/thermal/cpu-idle-cooling.rst | 18 ++++++++++++------ Documentation/driver-api/thermal/index.rst | 1 + 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/Documentation/driver-api/thermal/cpu-idle-cooling.rst b/Documentation/driver-api/thermal/cpu-idle-cooling.rst index 9f0016ee4cfb..357d2f023605 100644 --- a/Documentation/driver-api/thermal/cpu-idle-cooling.rst +++ b/Documentation/driver-api/thermal/cpu-idle-cooling.rst @@ -1,3 +1,9 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================ +CPU Idle Cooling +================ + Situation: ---------- @@ -45,7 +51,7 @@ idle state target residency, we lead to dropping the static and the dynamic leakage for this period (modulo the energy needed to enter this state). So the sustainable power with idle cycles has a linear relation with the OPP’s sustainable power and can be computed with a -coefficient similar to: +coefficient similar to:: Power(IdleCycle) = Coef x Power(OPP) @@ -136,7 +142,7 @@ Power considerations -------------------- When we reach the thermal trip point, we have to sustain a specified -power for a specific temperature but at this time we consume: +power for a specific temperature but at this time we consume:: Power = Capacitance x Voltage^2 x Frequency x Utilisation @@ -145,7 +151,7 @@ wrong in the system setup). The ‘Capacitance’ and ‘Utilisation’ are a fixed value, ‘Voltage’ and the ‘Frequency’ are fixed artificially because we don’t want to change the OPP. We can group the ‘Capacitance’ and the ‘Utilisation’ into a single term which is the -‘Dynamic Power Coefficient (Cdyn)’ Simplifying the above, we have: +‘Dynamic Power Coefficient (Cdyn)’ Simplifying the above, we have:: Pdyn = Cdyn x Voltage^2 x Frequency @@ -154,7 +160,7 @@ in order to target the sustainable power defined in the device tree. So with the idle injection mechanism, we want an average power (Ptarget) resulting in an amount of time running at full power on a specific OPP and idle another amount of time. That could be put in a -equation: +equation:: P(opp)target = ((Trunning x (P(opp)running) + (Tidle x P(opp)idle)) / (Trunning + Tidle) @@ -165,7 +171,7 @@ equation: At this point if we know the running period for the CPU, that gives us the idle injection we need. Alternatively if we have the idle -injection duration, we can compute the running duration with: +injection duration, we can compute the running duration with:: Trunning = Tidle / ((P(opp)running / P(opp)target) - 1) @@ -188,7 +194,7 @@ However, in this demonstration we ignore three aspects: target residency, otherwise we end up consuming more energy and potentially invert the mitigation effect -So the final equation is: +So the final equation is:: Trunning = (Tidle - Twakeup ) x (((P(opp)dyn + P(opp)static ) - P(opp)target) / P(opp)target ) diff --git a/Documentation/driver-api/thermal/index.rst b/Documentation/driver-api/thermal/index.rst index 5ba61d19c6ae..4cb0b9b6bfb8 100644 --- a/Documentation/driver-api/thermal/index.rst +++ b/Documentation/driver-api/thermal/index.rst @@ -8,6 +8,7 @@ Thermal :maxdepth: 1 cpu-cooling-api + cpu-idle-cooling sysfs-api power_allocator