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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C1FB2C43142 for ; Thu, 21 Jun 2018 23:19:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82A2922543 for ; Thu, 21 Jun 2018 23:19:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82A2922543 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=anholt.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932875AbeFUXT3 (ORCPT ); Thu, 21 Jun 2018 19:19:29 -0400 Received: from anholt.net ([50.246.234.109]:58986 "EHLO anholt.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932170AbeFUXT2 (ORCPT ); Thu, 21 Jun 2018 19:19:28 -0400 Received: from localhost (localhost [127.0.0.1]) by anholt.net (Postfix) with ESMTP id A7ADC10A1642; Thu, 21 Jun 2018 16:19:27 -0700 (PDT) X-Virus-Scanned: Debian amavisd-new at anholt.net Received: from anholt.net ([127.0.0.1]) by localhost (kingsolver.anholt.net [127.0.0.1]) (amavisd-new, port 10024) with LMTP id jRHQjpbrf1Yk; Thu, 21 Jun 2018 16:19:26 -0700 (PDT) Received: from eliezer.anholt.net (localhost [127.0.0.1]) by anholt.net (Postfix) with ESMTP id 6D47A10A0D3A; Thu, 21 Jun 2018 16:19:26 -0700 (PDT) Received: by eliezer.anholt.net (Postfix, from userid 1000) id CB9062FE21D0; Thu, 21 Jun 2018 16:19:25 -0700 (PDT) From: Eric Anholt To: Kevin Quigley , Andrzej Hajda , "dri-devel\@lists.freedesktop.org" Cc: Boris Brezillon , "linux-kernel\@vger.kernel.org" , James Hughes , Archit Taneja Subject: RE: [PATCH] drm/vc4: Enable the DSI module and link before other enables. In-Reply-To: References: <20180604194437.13790-1-eric@anholt.net> <20180605082532eucas1p21328ec5bea7d588c81480829f862bdfd~1NhnMydDJ0562405624eucas1p2l@eucas1p2.samsung.com> User-Agent: Notmuch/0.22.2+1~gb0bcfaa (http://notmuchmail.org) Emacs/25.2.2 (x86_64-pc-linux-gnu) Date: Thu, 21 Jun 2018 16:19:24 -0700 Message-ID: <87a7rnenib.fsf@anholt.net> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain Kevin Quigley writes: > Hi, > > When we talk about control bus enable and video transfer enable for > DSI, there is a mode in which control commands can be sent, > interleaved with the video. This is often done at the end-of-frame > and/or end of line. I've seen this handled in some other DSI device > drivers. In these cases, the driver has to look at the frame timing > in the video and carefully select the number of control bytes which > can be sent during the blanking periods. The number of bytes which > can be sent, is very much dependant on the panel-size and clock > frequencies... (which determines the blanking time). I'm not sure how > widely this is a feature in the DSI encoder HW, and/or implemented > purely in the drivers. That scheduling is done by the VC4 DSI encoder. > To conclude: I think that DSI encoder devices need to be able to > support sending control data (LPDA) - concurrently with video frames. I believe that should work already. --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEE/JuuFDWp9/ZkuCBXtdYpNtH8nugFAlssMnwACgkQtdYpNtH8 nuj6XhAAgldBul9TX+OY/OhzeAsWa+81VWWIec9ruWi5He5U4/UaCRIcr0/wKhop U3eAYS4E0X8OTcC+s/RqaVHRcmHfTOyoR23OXF2onfyvjibtYfapJ2XJUuGzPpLx inBoU0XvgONM7LyzkaxaAJ/Y40dQ5+vgOLZEy18W0Mu5QFUHvGu7mqSaI3Fg1LMh C3HCUJQKZMUuIwFaBfokZ1hPy7tq8SYnb6V5y3QjDntOF+4HYIYUfCZOejHQNw9M LFxyqf1khrrhgc6sVJYWqasEUPx2lssCGkUHPMeEhXHtV1k5Gpov87QU9gJG5tBQ M19pGRYAmG+2I5NYTMCWO6KxaGL31bX10KubPgz96FpgBMl/tfnU6/7M4fjvKC/O +RhK/SFtec5abOk7O3LCM5bEBywWSk8xXYDOoaYh38z8glDUydm4qwIxGFODJwBK TzkQfkgxirq7ElGjmAFgqWOWPTad0t/pUe+oQOu9YP2iAKVKS+XftpsGXImFvK/V 2l7JxzNkHRe+y7Pq1KZBUMZQNG91a2Z7P1hUjbmcFYDDR/cLCb9qpkJi+iWdVWN6 Eq9MpqXQKv3VwkAjsoSW5M7M+rZe+/jogQXaz4kWMJDgjjm2J3O86uBXfFsU1oAu Q1zEMuwe4Q4Qs22R4xvEmvsGRAx5jIz/9nwBTbmqH9s0nYN9528= =Hm3m -----END PGP SIGNATURE----- --=-=-=--