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[209.132.180.67]) by mx.google.com with ESMTP id l12-v6si8497329plc.54.2018.10.29.02.43.19; Mon, 29 Oct 2018 02:43:19 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of devicetree-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=h4QcNkmA; spf=pass (google.com: best guess record for domain of devicetree-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=devicetree-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729646AbeJ2SbK (ORCPT + 6 others); Mon, 29 Oct 2018 14:31:10 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:38430 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729613AbeJ2SbK (ORCPT ); Mon, 29 Oct 2018 14:31:10 -0400 Received: by mail-pf1-f194.google.com with SMTP id b11-v6so3729581pfi.5 for ; Mon, 29 Oct 2018 02:43:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=5RZ9FHApH+90jKzx3eFzIgtrpa6PgcJbkx7WWuT0bFI=; b=h4QcNkmAY1KJlxXLbVpKirKOIircySyjrVBhw99VhliOHE5iMiIXYAPV+wJVjNoizm erZeGDdSwmccg65uQ5rwAISY/O5KolymTm4b0U2th7L0u7x/F33EJ0qGSKK07iaJVR9m Vrcmpijg9OzG8gL4mPTeZyTIVXBTrOA3zCQnc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=5RZ9FHApH+90jKzx3eFzIgtrpa6PgcJbkx7WWuT0bFI=; b=MRtyfMh8iUd3GJw1uWMsb17iP9Kiky5G5zavFaAaysuWXR9K9r7BlNWtfB227OPmZ2 jrNrhxflfC+VU07N6xaloCyM7EAaeFb3uqnaiJMNIHw8WIHYAizHevvUFtxU89eBd4mB xMVgQOC/xCa9l+VzkP6ttO8ahHK75awVLB4Rlpx1kxGsFBMa/O/oVrfRMZevxxryGEmC jZto0lM6J94BQDl/DqBWxAoj9XqK34tUqX2kSqqFe+gU+HHq0zIJafA+VR9CXmPt15eP KeDUTjR7AzBwOVpkcfB5Nmo/KthR26qNAWaj/1nKpS8JLRhDSwYZhjeNCgyBZCs7oFOZ OeWQ== X-Gm-Message-State: AGRZ1gKorjY+J+vgXX03kGWWQKpycPcH3nI2IrWvvVfeZM2pUIDP7bR/ CR/lvchkvBv1YckjuiWmkjlr2g== X-Received: by 2002:a63:5308:: with SMTP id h8-v6mr12856854pgb.358.1540806196626; Mon, 29 Oct 2018 02:43:16 -0700 (PDT) Received: from localhost ([122.172.56.94]) by smtp.gmail.com with ESMTPSA id 124-v6sm13449129pfb.132.2018.10.29.02.43.15 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 29 Oct 2018 02:43:15 -0700 (PDT) From: Viresh Kumar To: catalin.marinas@arm.com, Rob Herring , Mark Rutland Cc: Viresh Kumar , linux-arm-kernel@lists.infradead.org, Vincent Guittot , Daniel Lezcano , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH V2] dt-bindings: arm: Explain capacities-dmips-mhz calculations in example Date: Mon, 29 Oct 2018 15:13:05 +0530 Message-Id: <1cd2594fff3fb54948dcd2af65ae1867dd1c541a.1540806119.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 2.19.1.568.g152ad8e3369a MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The example contains two values for the capacity currently, 446 in text and 578 in code. The numbers are all correct but can confuse some of the readers. This patch tries to explain how the numbers are calculated to avoid same confusion going forward. Acked-by: Daniel Lezcano Signed-off-by: Viresh Kumar --- V1->V2: - The numbers weren't incorrect in the example, just that it needs a bit more explanation for some people. Documentation/devicetree/bindings/arm/cpu-capacity.txt | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) -- 2.19.1.568.g152ad8e3369a diff --git a/Documentation/devicetree/bindings/arm/cpu-capacity.txt b/Documentation/devicetree/bindings/arm/cpu-capacity.txt index 9b5685a1d15d..84262cdb8d29 100644 --- a/Documentation/devicetree/bindings/arm/cpu-capacity.txt +++ b/Documentation/devicetree/bindings/arm/cpu-capacity.txt @@ -59,9 +59,11 @@ mhz values (normalized w.r.t. the highest value found while parsing the DT). =========================================== Example 1 (ARM 64-bit, 6-cpu system, two clusters): -capacities-dmips-mhz are scaled w.r.t. 1024 (cpu@0 and cpu@1) -supposing cluster0@max-freq=1100 and custer1@max-freq=850, -final capacities are 1024 for cluster0 and 446 for cluster1 +The capacities-dmips-mhz or DMIPS/MHz values (scaled to 1024) +are 1024 and 578 for cluster0 and cluster1. Further normalization +is done by the operating system based on cluster0@max-freq=1100 and +custer1@max-freq=850, final capacities are 1024 for cluster0 and +446 for cluster1 (576*850/1100). cpus { #address-cells = <2>;