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=-11.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 F22B6C4708F for ; Wed, 2 Jun 2021 10:58:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D5765613D2 for ; Wed, 2 Jun 2021 10:58:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232369AbhFBK7z (ORCPT ); Wed, 2 Jun 2021 06:59:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:39944 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230382AbhFBK6o (ORCPT ); Wed, 2 Jun 2021 06:58:44 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5FF1460FF2; Wed, 2 Jun 2021 10:57:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622631422; bh=4Kqd06H4tk196Fea2oUyUzPCeW3WtfbykgTc6Olq6aI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NQ54KWhccDSvwlRvVWIWPFBMdCHFM40ckBKp6C0O5pVbaEfpXntyDYDIZR1FIkfVd b03Za3uUGuo/Zj39zpCr1+1lWnv/u0cP4LFi/yd7RtFku3JFlWJf2ZxwT5f7jAgsBP bcQ92lU7Z9HmuqOmHCs32ugqc6ToKMXLQ97btza9X9vl98ZMo0BBTIX/hXmN+tlrjz s3ZeJunw3tPwq38VH4nTDl4fOD0zztQYA6ctd/OsneYD22ko3V9NN+aP7lTyWMDVOC +ZIfuUA6BIgJOAP78YqTd1+yvM9FzcKekN/MsRDOCMeAnVXT1CsRs9IVj5IU+JMc3u k3H3NIyX1NJ8A== Date: Wed, 2 Jun 2021 16:26:58 +0530 From: Vinod Koul To: Jeffrey Hugo Cc: Rob Clark , DTML , Jonathan Marek , David Airlie , MSM , lkml , Abhinav Kumar , Bjorn Andersson , Rob Herring , "open list:DRM PANEL DRIVERS" , Daniel Vetter , Dmitry Baryshkov , freedreno Subject: Re: [Freedreno] [RFC PATCH 00/13] drm/msm: Add Display Stream Compression Support Message-ID: References: <20210521124946.3617862-1-vkoul@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 26-05-21, 09:00, Jeffrey Hugo wrote: > On Tue, May 25, 2021 at 11:46 PM Vinod Koul wrote: > > On 21-05-21, 08:09, Jeffrey Hugo wrote: > > > On Fri, May 21, 2021 at 6:50 AM Vinod Koul wrote: > > > > > > > > Display Stream Compression (DSC) compresses the display stream in host which > > > > is later decoded by panel. This series enables this for Qualcomm msm driver. > > > > This was tested on Google Pixel3 phone which use LGE SW43408 panel. > > > > > > > > The changes include adding DT properties for DSC then hardware blocks support > > > > required in DPU1 driver and support in encoder. We also add support in DSI > > > > and introduce required topology changes. > > > > > > > > In order for panel to set the DSC parameters we add dsc in drm_panel and set > > > > it from the msm driver. > > > > > > > > Complete changes which enable this for Pixel3 along with panel driver (not > > > > part of this series) and DT changes can be found at: > > > > git.linaro.org/people/vinod.koul/kernel.git pixel/dsc_rfc > > > > > > > > Comments welcome! > > > > > > This feels backwards to me. I've only skimmed this series, and the DT > > > changes didn't come through for me, so perhaps I have an incomplete > > > view. > > > > Not sure why, I see it on lore: > > https://lore.kernel.org/dri-devel/20210521124946.3617862-3-vkoul@kernel.org/ > > > > > DSC is not MSM specific. There is a standard for it. Yet it looks > > > like everything is implemented in a MSM specific way, and then pushed > > > to the panel. So, every vendor needs to implement their vendor > > > specific way to get the DSC info, and then push it to the panel? > > > Seems wrong, given there is an actual standard for this feature. > > > > I have added slice and bpp info in the DT here under the host and then > > pass the generic struct drm_dsc_config to panel which allows panel to > > write the pps cmd > > > > Nothing above is MSM specific.. It can very well work with non MSM > > controllers too. > > I disagree. > > The DT bindings you defined (thanks for the direct link) are MSM > specific. I'm not talking (yet) about the properties you defined, but > purely from the stand point that you defined the binding within the > scope of the MSM dsi binding. No other vendor can use those bindings. > Of course, if we look at the properties themselves, they are prefixed > with "qcom", which is vendor specific. > > So, purely on the face of it, this is MSM specific. > > Assuming we want a DT solution for DSC, I think it should be something > like Documentation/devicetree/bindings/clock/clock-bindings.txt (the > first example that comes to mind), which is a non-vendor specific > generic set of properties that each vendor/device specific binding can > inherit. Panel has similar things. > > Specific to the properties, I don't much like that you duplicate BPP, > which is already associated with the panel (although perhaps not in > the scope of DT). What if the panel and your DSC bindings disagree? > Also, I guess I need to ask, have you read the DSC spec? Last I > looked, there were something like 3 dozen properties that could be > configured. You have five in your proposed binding. To me, this is > not a generic DSC solution, this is MSM specific (and frankly I don't > think this supports all the configuration the MSM hardware can do, > either). I would concede the point that DT is msm specific. I dont disagree on making them a common dsc biding which anyone can use. I think your idea does have merits... I am still not sure who should include these properties, would it be the panel or host. Either would work and rest of the system can use these properties... -- ~Vinod 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=-8.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,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 A0415C47083 for ; Wed, 2 Jun 2021 10:57:04 +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 706B7613BF for ; Wed, 2 Jun 2021 10:57:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 706B7613BF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C4C366E3D2; Wed, 2 Jun 2021 10:57:03 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id 60CCE6E3C1; Wed, 2 Jun 2021 10:57:02 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 5FF1460FF2; Wed, 2 Jun 2021 10:57:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622631422; bh=4Kqd06H4tk196Fea2oUyUzPCeW3WtfbykgTc6Olq6aI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NQ54KWhccDSvwlRvVWIWPFBMdCHFM40ckBKp6C0O5pVbaEfpXntyDYDIZR1FIkfVd b03Za3uUGuo/Zj39zpCr1+1lWnv/u0cP4LFi/yd7RtFku3JFlWJf2ZxwT5f7jAgsBP bcQ92lU7Z9HmuqOmHCs32ugqc6ToKMXLQ97btza9X9vl98ZMo0BBTIX/hXmN+tlrjz s3ZeJunw3tPwq38VH4nTDl4fOD0zztQYA6ctd/OsneYD22ko3V9NN+aP7lTyWMDVOC +ZIfuUA6BIgJOAP78YqTd1+yvM9FzcKekN/MsRDOCMeAnVXT1CsRs9IVj5IU+JMc3u k3H3NIyX1NJ8A== Date: Wed, 2 Jun 2021 16:26:58 +0530 From: Vinod Koul To: Jeffrey Hugo Subject: Re: [Freedreno] [RFC PATCH 00/13] drm/msm: Add Display Stream Compression Support Message-ID: References: <20210521124946.3617862-1-vkoul@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: DTML , Jonathan Marek , David Airlie , MSM , lkml , Abhinav Kumar , Bjorn Andersson , Rob Herring , "open list:DRM PANEL DRIVERS" , Dmitry Baryshkov , freedreno Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 26-05-21, 09:00, Jeffrey Hugo wrote: > On Tue, May 25, 2021 at 11:46 PM Vinod Koul wrote: > > On 21-05-21, 08:09, Jeffrey Hugo wrote: > > > On Fri, May 21, 2021 at 6:50 AM Vinod Koul wrote: > > > > > > > > Display Stream Compression (DSC) compresses the display stream in host which > > > > is later decoded by panel. This series enables this for Qualcomm msm driver. > > > > This was tested on Google Pixel3 phone which use LGE SW43408 panel. > > > > > > > > The changes include adding DT properties for DSC then hardware blocks support > > > > required in DPU1 driver and support in encoder. We also add support in DSI > > > > and introduce required topology changes. > > > > > > > > In order for panel to set the DSC parameters we add dsc in drm_panel and set > > > > it from the msm driver. > > > > > > > > Complete changes which enable this for Pixel3 along with panel driver (not > > > > part of this series) and DT changes can be found at: > > > > git.linaro.org/people/vinod.koul/kernel.git pixel/dsc_rfc > > > > > > > > Comments welcome! > > > > > > This feels backwards to me. I've only skimmed this series, and the DT > > > changes didn't come through for me, so perhaps I have an incomplete > > > view. > > > > Not sure why, I see it on lore: > > https://lore.kernel.org/dri-devel/20210521124946.3617862-3-vkoul@kernel.org/ > > > > > DSC is not MSM specific. There is a standard for it. Yet it looks > > > like everything is implemented in a MSM specific way, and then pushed > > > to the panel. So, every vendor needs to implement their vendor > > > specific way to get the DSC info, and then push it to the panel? > > > Seems wrong, given there is an actual standard for this feature. > > > > I have added slice and bpp info in the DT here under the host and then > > pass the generic struct drm_dsc_config to panel which allows panel to > > write the pps cmd > > > > Nothing above is MSM specific.. It can very well work with non MSM > > controllers too. > > I disagree. > > The DT bindings you defined (thanks for the direct link) are MSM > specific. I'm not talking (yet) about the properties you defined, but > purely from the stand point that you defined the binding within the > scope of the MSM dsi binding. No other vendor can use those bindings. > Of course, if we look at the properties themselves, they are prefixed > with "qcom", which is vendor specific. > > So, purely on the face of it, this is MSM specific. > > Assuming we want a DT solution for DSC, I think it should be something > like Documentation/devicetree/bindings/clock/clock-bindings.txt (the > first example that comes to mind), which is a non-vendor specific > generic set of properties that each vendor/device specific binding can > inherit. Panel has similar things. > > Specific to the properties, I don't much like that you duplicate BPP, > which is already associated with the panel (although perhaps not in > the scope of DT). What if the panel and your DSC bindings disagree? > Also, I guess I need to ask, have you read the DSC spec? Last I > looked, there were something like 3 dozen properties that could be > configured. You have five in your proposed binding. To me, this is > not a generic DSC solution, this is MSM specific (and frankly I don't > think this supports all the configuration the MSM hardware can do, > either). I would concede the point that DT is msm specific. I dont disagree on making them a common dsc biding which anyone can use. I think your idea does have merits... I am still not sure who should include these properties, would it be the panel or host. Either would work and rest of the system can use these properties... -- ~Vinod