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=-5.5 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 7BB98C433B4 for ; Tue, 20 Apr 2021 21:25:27 +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 2AE97613F5 for ; Tue, 20 Apr 2021 21:25:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2AE97613F5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=amd-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2605E6E8ED; Tue, 20 Apr 2021 21:25:22 +0000 (UTC) Received: from mail-ot1-x32b.google.com (mail-ot1-x32b.google.com [IPv6:2607:f8b0:4864:20::32b]) by gabe.freedesktop.org (Postfix) with ESMTPS id DA6CA6E8DD; Tue, 20 Apr 2021 21:25:20 +0000 (UTC) Received: by mail-ot1-x32b.google.com with SMTP id i26-20020a9d625a0000b02902a2119f7613so329567otk.10; Tue, 20 Apr 2021 14:25:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=+94cd/jX9sjDc89stbH05qMt3apklq+Yobx3TwJ2KJw=; b=KayuPQnJClOx7SM+PA/ikbJmWWeVZQ3AHc/Gkw2ZgmSgRSuhjGdYbkFUyAkh7bOZAI PYWleZGj6bNHtoNmMh0ymLJlCT5A0cwZ8kz1BqDTWqGenWmjLC7VtQIdMh1ImLLl/MSp FIP2ixfRj1kGzzxXL9TD0Amm+/0Fo6/GUGidgONU8+S3DvG0fY3gjJG8G47MhUdM/NdJ K406CydUhI/RK8Q8SLB4dq44knKEhnMXNx3Gql92D/H2xZNG3ZznraXOrSzG8RLDOtNw U0D9Qfux1R1gLu+ZHi7siK6oJ+VgE0rh18hJTC5v38+abqf9lCbBX2rnsq82FfgzkTyQ XWHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=+94cd/jX9sjDc89stbH05qMt3apklq+Yobx3TwJ2KJw=; b=VaBP5XzjPKmIZb2IPt2Rd9h9t73KatkMJGto9ZaQ0ZHI0SArDGLPnXgwUEuu/LckSZ aHNeWrjW0Atiy0tun4cbO5j14WP2HLCmk+T04kZ/jlrrozLg4BR3nAGTmBzGA5yxeWeT zuds/GnQxWiPt1/zLV4x/G0C7PXz5yXwkN/RigXOjrz3Ol0WB28dCmu0bsSP00Vv9FiH Sir1kxu0thM2AEfTlcBgXLsVssUqrLdjihsOh32dVn1otgttbS/4El6cdeENfuxoJ4OV kKMr/6siwZb5PONNNHfcAmxmQ9CWJW9LOR3Sin3e8kwbzM6LgTAn5HROgzrg4t1eE3Jk 1WWw== X-Gm-Message-State: AOAM533CTwEp83t12NPHm/jucYNplE9+P9MhNxtmGQLvmQ8i7JpzjBvb 03ZTgv8B6E7WChaVM0PGbZ/N9fKO5rYsu8I7E2o= X-Google-Smtp-Source: ABdhPJyEBWlFxv39cCh3Ez/LGgDffyoElnokJUk8cIivV3xK6XxgEqMrnr1nVRtkJRUWiMnZ09qy7OgulHhQi+5fbP0= X-Received: by 2002:a05:6830:15d3:: with SMTP id j19mr11040215otr.23.1618953920151; Tue, 20 Apr 2021 14:25:20 -0700 (PDT) MIME-Version: 1.0 References: <20210319210317.32369-1-mario.kleiner.de@gmail.com> In-Reply-To: From: Alex Deucher Date: Tue, 20 Apr 2021 17:25:09 -0400 Message-ID: Subject: Re: 16 bpc fixed point (RGBA16) framebuffer support for core and AMD. To: Mario Kleiner X-BeenThere: amd-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alex Deucher , dri-devel , amd-gfx list , Nicholas Kazlauskas Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: amd-gfx-bounces@lists.freedesktop.org Sender: "amd-gfx" On Fri, Apr 16, 2021 at 12:29 PM Mario Kleiner wrote: > > Friendly ping to the AMD people. Nicholas, Harry, Alex, any feedback? > Would be great to get this in sooner than later. > No objections from me. Alex > Thanks and have a nice weekend, > -mario > > On Fri, Mar 19, 2021 at 10:03 PM Mario Kleiner > wrote: > > > > Hi, > > > > this patch series adds the fourcc's for 16 bit fixed point unorm > > framebuffers to the core, and then an implementation for AMD gpu's > > with DisplayCore. > > > > This is intended to allow for pageflipping to, and direct scanout of, > > Vulkan swapchain images in the format VK_FORMAT_R16G16B16A16_UNORM. > > I have patched AMD's GPUOpen amdvlk OSS driver to enable this format > > for swapchains, mapping to DRM_FORMAT_XBGR16161616: > > Link: https://github.com/kleinerm/pal/commit/a25d4802074b13a8d5f7edc96ae45469ecbac3c4 > > > > My main motivation for this is squeezing every bit of precision > > out of the hardware for scientific and medical research applications, > > where fp16 in the unorm range is limited to ~11 bpc effective linear > > precision in the upper half [0.5;1.0] of the unorm range, although > > the hardware could do at least 12 bpc. > > > > It has been successfully tested on AMD RavenRidge (DCN-1), and with > > Polaris11 (DCE-11.2). Up to two displays were active on RavenRidge > > (DP 2560x1440@144Hz + HDMI 2560x1440@120Hz), the maximum supported > > on my hw, both running at 10 bpc DP output depth. > > > > Up to three displays were active on the Polaris (DP 2560x1440@144Hz + > > 2560x1440@100Hz USB-C DP-altMode-to-HDMI converter + eDP 2880x1800@60Hz > > Apple Retina panel), all running at 10 bpc output depth. > > > > No malfunctions, visual artifacts or other oddities were observed > > (apart from an adventureous mess of cables and adapters on my desk), > > suggesting it works. > > > > I used my automatic photometer measurement procedure to verify the > > effective output precision of 10 bpc DP native signal + spatial > > dithering in the gpu as enabled by the amdgpu driver. Results show > > the expected 12 bpc precision i hoped for -- the current upper limit > > for AMD display hw afaik. > > > > So it seems to work in the way i hoped :). > > > > Some open questions wrt. AMD DC, to be addressed in this patch series, or follow up > > patches if neccessary: > > > > - For the atomic check for plane scaling, the current patch will > > apply the same hw limits as for other rgb fixed point fb's, e.g., > > for 8 bpc rgb8. Is this correct? Or would we need to use the fp16 > > limits, because this is also a 64 bpp format? Or something new > > entirely? > > > > - I haven't added the new fourcc to the DCC tables yet. Should i? > > > > - I had to change an assert for DCE to allow 36bpp linebuffers (patch 4/5). > > It looks to me as if that assert was inconsistent with other places > > in the driver where COLOR_DEPTH121212 is supported, and looking at > > the code, the change seems harmless. At least on DCE-11.2 the change > > didn't cause any noticeable (by myself) or measurable (by my equipment) > > problems on any of the 3 connected displays. > > > > - Related to that change, while i needed to increase lb pixelsize to 36bpp > > to get > 10 bpc effective precision on DCN, i didn't need to do that > > on DCE. Also no change of lb pixelsize was needed on either DCN or DCe > > to get > 10 bpc precision for fp16 framebuffers, so something seems to > > behave differently for floating point 16 vs. fixed point 16. This all > > seems to suggest one could leave lb pixelsize at the old 30 bpp value > > on at least DCE-11.2 and still get the > 10 bpc precision if one wanted > > to avoid the changes of patch 4/5. > > > > Thanks, > > -mario > > > > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel _______________________________________________ amd-gfx mailing list amd-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx