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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 83A22C33CB2 for ; Fri, 31 Jan 2020 11:52:07 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5D77520707 for ; Fri, 31 Jan 2020 11:52:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5D77520707 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F1EAF6E96F; Fri, 31 Jan 2020 11:52:06 +0000 (UTC) Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by gabe.freedesktop.org (Postfix) with ESMTPS id 617426E96F for ; Fri, 31 Jan 2020 11:52:05 +0000 (UTC) X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 31 Jan 2020 03:52:03 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,385,1574150400"; d="scan'208";a="247706414" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by orsmga002.jf.intel.com with SMTP; 31 Jan 2020 03:51:59 -0800 Received: by stinkbox (sSMTP sendmail emulation); Fri, 31 Jan 2020 13:51:59 +0200 Date: Fri, 31 Jan 2020 13:51:59 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Jani Nikula Message-ID: <20200131115159.GM13686@intel.com> References: <20200131063038.GA15798@plaxmina-desktop.iind.intel.com> <87pnez99ou.fsf@intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87pnez99ou.fsf@intel.com> X-Patchwork-Hint: comment User-Agent: Mutt/1.10.1 (2018-07-13) Subject: Re: [Intel-gfx] RFC: pipe writeback design for i915 X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: intel-gfx@lists.freedesktop.org Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Fri, Jan 31, 2020 at 12:55:45PM +0200, Jani Nikula wrote: > On Fri, 31 Jan 2020, "Bharadiya,Pankaj" wrote: > > I am exploring the way of implementing the pipe writeback feature in i9= 15 and > > would like to get early feedback on design. > > > > We have a Wireless display(WD) transcoder which can be used for capturi= ng > > display pipe output to memory. It is generally intended for wireless di= splay, > > but can be used for other functions such as in validation automation wh= ere crc > > based comparison is not feasible. > = > I think you should probably explore the use case and driver/igt impact > further before embarking on the implementation. > = > - How much do you need to modify existing code in kernel and igt to make > use of writeback connectors? > = > - What kind of test coverage do you get? Pipe CRC is used in connection > with the physical encoders. In contrast, you won't have that with WD > transcoders. (Design wise I think this may mean you'll also need > "writeback encoders", instead of trying to plug it into existing > encoders.) So you'll only test the pipe side of things, which roughly > corresponds to pipe CRC coverage I guess. I guess it could speed up > that part of testing because you can then skip the physical > connectors, but you do have to test them also. So it's not a panacea. The main benefit I'm looking forward to is for reverse engineering. As in answwering the age old question: "let me see wtf the hw is actually doing to my pixels?". I want this! -- = Ville Syrj=E4l=E4 Intel --------------------------------------------------------------------- Intel Finland Oy Registered Address: PL 281, 00181 Helsinki = Business Identity Code: 0357606 - 4 = Domiciled in Helsinki = This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx