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=-6.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,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 EEB9DC47092 for ; Wed, 2 Jun 2021 11:01:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0D3D610E5 for ; Wed, 2 Jun 2021 11:01:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231187AbhFBLDY (ORCPT ); Wed, 2 Jun 2021 07:03:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:40838 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229695AbhFBLDX (ORCPT ); Wed, 2 Jun 2021 07:03:23 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9325C60FF2; Wed, 2 Jun 2021 11:01:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622631700; bh=X1r+/2vqrhf2eopgUmFN+gmnFQ6uhol2dVCw4nc+dR4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TJKit5piuyWTiZE2++rnwBc+NWnC2oVLAFRNuEEhQCVKac8lXQjlMiqUjfKJ+0+2g loDXAsOAAiNwUIewxgKX7kcLZgbBu2928pW7IbObJBT/qPH8uJ1pTyLoX+Cne1BGRP oQUlve0vN2S3bU9ECooK7eF3uPC7GbIvvsqSoCpCNvvvYE9DGtGqiVI19Qh3D6fyhJ DXO0D4CgfnUrVMnl5hWpukOKLvDe/wEGnDkz5qViZsH2e5EbY0zeY3/kd78I6XWlpd AYo6ZSaGnX6rpyBOM5GKVQX7N4xWngbhqqvmz9PvjA4tco2EykT2QndUrW/vAKy/z6 jNrq8I6s7Fh2A== Date: Wed, 2 Jun 2021 16:31:36 +0530 From: Vinod Koul To: Rob Clark Cc: Jeffrey Hugo , 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 27-05-21, 16:30, Rob Clark wrote: > On Wed, May 26, 2021 at 8:00 AM Jeffrey Hugo wrote: > > On Tue, May 25, 2021 at 11:46 PM Vinod Koul wrote: > > Frankly, I don't like the MSM ACPI solution that I've seen on the laptops. > > The ACPI assumes the entire MDSS (including DSI parts) and GPU is one > > device, and ultimately handled by one driver. That driver needs to > > get a value from UEFI (set by the bootloader) that is the "panel id". > > Then the driver calls into ACPI (I think its _ROM, but I might be > > mistaken, doing this from memory) with that id. It gets back a binary > > blob which is mostly an xml file (format is publicly documented) that > > contains the panel timings and such. > > tbh, I kinda suspect that having a single "gpu" device (which also > includes venus, in addition to display, IIRC) in the ACPI tables is a > windowsism, trying to make things look to userspace like a single "GPU > card" in the x86 world.. but either way, I think the ACPI tables on > the windows arm laptops which use dsi->bridge->edp is too much of a > lost cause to even consider here. Possibly ACPI boot on these devices > would be more feasible on newer devices which have direct eDP out of > the SoC without requiring external bridge/panel glue. yeah that is always a very different world. although it might make sense to use information in tables and try to deduce information about the system can be helpful... > I'd worry more about what makes sense in a DT world, when it comes to > DT bindings. And do you have thoughts on that..? -- ~Vinod