From patchwork Mon Feb 17 16:20:19 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: 11386863 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 EB4B61580 for ; Mon, 17 Feb 2020 16:20:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD02C24670 for ; Mon, 17 Feb 2020 16:20:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581956452; bh=GXfnyk+5mxcLxh7DS10kpV2zW4ajtTvIlfSvgF1m6HE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ZUrc/zOfKSEWUnFzTMl0FAm7RHbpOlmU5Lcu3FS5skr8W5u6zJrOygJSIz0XA24Zt IXGyj7XmaesV6wHgObRRBZjhVeQUlSAl7XU05DUBhCd6Zej3Y12LJoLSUd+3fVHMW5 b3ZsIiTrGkVq3JWEK3Yh06BWUVdIhV6VFv4WbyOo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728692AbgBQQUr (ORCPT ); Mon, 17 Feb 2020 11:20:47 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:54966 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728476AbgBQQUr (ORCPT ); Mon, 17 Feb 2020 11:20:47 -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=V8Gn2+nNEW0XD7O/RskUVtUmAc 5wOo0wKXc5QuWC8OTHgzcElE3z3DtOzZfXmqnanL8KD+0Y2q1YJrxMeGAZFGYEYlgnHPry06/IZyq h0DQsINTAXRbx8AFw0stk3d06FMhkDQ/VnaZUwpO/XeCr5r5dVlbHpBvABw//guL5EL3+Ipwh2Hes Wf7Cw0C5BzVCxyOkQGkGxctdRDfFPcuEZqv5VqMw9XR5gBt46Y3xI+mT4CSAgTAOoGzO+ahrEJqtT M8lUiHFr5TM3POASvq+jzypM0Z4pOv+Oj6tSnE6s6j7EKxlMAbfHJADB99ygREBwLIzUwimFrmJ2d SKFfodKg==; Received: from ip-109-41-129-189.web.vodafone.de ([109.41.129.189] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1j3j8X-000420-QT; Mon, 17 Feb 2020 16:20:46 +0000 Received: from mchehab by bombadil.infradead.org with local (Exim 4.92.3) (envelope-from ) id 1j3j8V-000fod-QO; Mon, 17 Feb 2020 17:20:43 +0100 From: Mauro Carvalho Chehab To: Linux Doc Mailing List Cc: Mauro Carvalho Chehab , Jonathan Corbet , Amit Daniel Kachhap , Daniel Lezcano , Viresh Kumar , Javi Merino , linux-pm@vger.kernel.org Subject: [PATCH v2 01/24] docs: thermal: convert cpu-idle-cooling.rst to ReST Date: Mon, 17 Feb 2020 17:20:19 +0100 Message-Id: X-Mailer: git-send-email 2.24.1 In-Reply-To: References: MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@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