From patchwork Wed Jun 14 06:30:16 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 9787739 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 15746602CB for ; Thu, 15 Jun 2017 00:58:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0A78A284DC for ; Thu, 15 Jun 2017 00:58:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F2D83284ED; Thu, 15 Jun 2017 00:58:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3C7F6284DC for ; Thu, 15 Jun 2017 00:58:29 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4DB076E668; Thu, 15 Jun 2017 00:57:39 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from wens.csie.org (mirror2.csie.ntu.edu.tw [140.112.30.76]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1670989DFB for ; Wed, 14 Jun 2017 06:30:20 +0000 (UTC) Received: by wens.csie.org (Postfix, from userid 1000) id F1FBC60062; Wed, 14 Jun 2017 14:30:16 +0800 (CST) From: Chen-Yu Tsai To: Maxime Ripard , David Airlie , Rob Herring , Mark Rutland Subject: [PATCH] dt-bindings: display: sunxi: Improve endpoint ID scheme readability Date: Wed, 14 Jun 2017 14:30:16 +0800 Message-Id: <20170614063016.22069-1-wens@csie.org> X-Mailer: git-send-email 2.11.0 X-Mailman-Approved-At: Thu, 15 Jun 2017 00:57:20 +0000 Cc: devicetree@vger.kernel.org, Chen-Yu Tsai , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The explanation for the endpoint ID numbering scheme is convoluted and hard to understand. This patch aims to improve the readability of it by combining the existing two paragraphs, while also providing a diagram example, and how endpoints should be numbered based on that example. Signed-off-by: Chen-Yu Tsai Acked-by: Rob Herring --- Hope this helps. I'm not sure I can improve this even more without spelling out all cases. --- .../bindings/display/sunxi/sun4i-drm.txt | 36 ++++++++++++++++------ 1 file changed, 27 insertions(+), 9 deletions(-) diff --git a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt index b83e6018041d..70885041553a 100644 --- a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt +++ b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt @@ -4,15 +4,33 @@ Allwinner A10 Display Pipeline The Allwinner A10 Display pipeline is composed of several components that are going to be documented below: -For the input port of all components up to the TCON in the display -pipeline, if there are multiple components, the local endpoint IDs -must correspond to the index of the upstream block. For example, if -the remote endpoint is Frontend 1, then the local endpoint ID must -be 1. - -Conversely, for the output ports of the same group, the remote endpoint -ID must be the index of the local hardware block. If the local backend -is backend 1, then the remote endpoint ID must be 1. +For all connections between components up to the TCONs in the display +pipeline, when there are multiple components of the same type at the +same depth, the local endpoint ID must be the same as the remote +component's index. For example, if the remote endpoint is Frontend 1, +then the local endpoint ID must be 1. + + Frontend 0 [0] ----------- [0] Backend 0 [0] ----- [0] TCON 0 + [1] ---- ---- [1] + \ / + X + / \ + [0] ---- ---- [0] + Frontend 1 [1] ----------- [1] Backend 1 [0] ----- [0] TCON 1 + +For a two pipeline system such as the one depicted above, the lines +represent the connections between the components, while the numbers +within the square brackets corresponds to the ID of the local endpoint. + +The same rule also applies to DE 2.0 mixer-TCON connections: + + Mixer 0 [0] ----------- [0] TCON 0 + [1] ---- ---- [1] + \ / + X + / \ + [0] ---- ---- [0] + Mixer 1 [1] ----------- [1] TCON 1 HDMI Encoder ------------