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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,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 D8B6EC433B4 for ; Tue, 20 Apr 2021 08:46:53 +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 7505B6101D for ; Tue, 20 Apr 2021 08:46:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7505B6101D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch 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 8DF616E12C; Tue, 20 Apr 2021 08:46:52 +0000 (UTC) Received: from mail-ej1-x62c.google.com (mail-ej1-x62c.google.com [IPv6:2a00:1450:4864:20::62c]) by gabe.freedesktop.org (Postfix) with ESMTPS id 816046E12C for ; Tue, 20 Apr 2021 08:46:51 +0000 (UTC) Received: by mail-ej1-x62c.google.com with SMTP id w3so57090570ejc.4 for ; Tue, 20 Apr 2021 01:46:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=vuclwn4vyYALU0qWvo6KCdEtoH/58AhLvrs6PmwRMkU=; b=d6k/+pMNRaJAPmCwZIx46LdCjEclIZQZIiqmt5R+9oE2HbK/SUZCyy9PgG7R/SdRV5 +qqmMuLhWyBlELzXKxtTUWe/a/F923nSFKxOiKEcHGTTAXjjfYZKxixldu4HVwNbjrvS goh8h0wa7opFwUTqajn0mk7R0ka7M8qA/THy4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=vuclwn4vyYALU0qWvo6KCdEtoH/58AhLvrs6PmwRMkU=; b=bFiaSUcFLdv1VF1KGKTdndsBrCamcbAfkoUY4DjZ2LAdk96E6Zk77vxt+n+y9EzRBP GwqkfUQkiBRwtQweSQSxHV1y9GGuAjIggToW9rZDMqnImqAUSd0fyWvUpNKQJLEF/fJV bmsAj4PhrBNEhWg5bykFhpvjLKUsOczeTIpAGXR0OaONSlq/YhV5OPrwu1S8o5NYLb/M yunaAeYrX+0/mEzfobMYYx4udX4jJ7q53PiXyy7mJuoC/kDX3E9+GLpUOFtN2rcAV48C 5YLxtYjPf0tgazasgZ4DYZ1IInMDEzWxI3tUjvI9jSCt4HTNRCY644YOFQ6AQHi5vQ27 jpoQ== X-Gm-Message-State: AOAM530PMdwne9+8TDR9ASCdz9JjiCxWPP7y8GWDMFhfVoWx07JTRqXF Hf/PYfXp8PH7kmSk7E9huP59cg== X-Google-Smtp-Source: ABdhPJyhF872h1aJTtsSGthH1G/y01DLyqPuLLT/uw2mQIUL7MPcOuFmVGGTl/E/UJzUQ97XvDsuxw== X-Received: by 2002:a17:906:53cd:: with SMTP id p13mr26254640ejo.379.1618908410246; Tue, 20 Apr 2021 01:46:50 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id n14sm11973365ejy.90.2021.04.20.01.46.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 20 Apr 2021 01:46:49 -0700 (PDT) Date: Tue, 20 Apr 2021 10:46:47 +0200 From: Daniel Vetter To: Geert Uytterhoeven Subject: Re: [PATCH v4 0/9] drm: Support simple-framebuffer devices and firmware fbs Message-ID: References: <20210416090048.11492-1-tzimmermann@suse.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-Operating-System: Linux phenom 5.7.0-1-amd64 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: bluescreen_avenger@verizon.net, Thomas Zimmermann , Jonathan Corbet , David Airlie , Emil Velikov , DRI Development , "open list:DOCUMENTATION" , Liam Girdwood , virtualization@lists.linux-foundation.org, Hans de Goede , Mark Brown , Gerd Hoffmann , Greg KH , Sam Ravnborg Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Apr 19, 2021 at 10:00:56AM +0200, Geert Uytterhoeven wrote: > Hi Thomas, > > On Fri, Apr 16, 2021 at 11:00 AM Thomas Zimmermann wrote: > > This patchset adds support for simple-framebuffer platform devices and > > a handover mechanism for native drivers to take-over control of the > > hardware. > > > > The new driver, called simpledrm, binds to a simple-frambuffer platform > > device. The kernel's boot code creates such devices for firmware-provided > > framebuffers, such as EFI-GOP or VESA. Typically the BIOS, UEFI or boot > > loader sets up the framebuffers. Description via device tree is also an > > option. > > I guess this can be used as a replacement for offb, too... > > > Patches 4 to 8 add the simpledrm driver. It's build on simple DRM helpers > > and SHMEM. It supports 16-bit, 24-bit and 32-bit RGB framebuffers. During > > .... if support for 8-bit frame buffers would be added? Is that 8-bit greyscale or 8-bit indexed with 256 entry palette? Former shouldn't be a big thing, but the latter is only really supported by the overall drm ecosystem in theory. Most userspace assumes that xrgb8888 works, and we keep that illusion up by emulating it in kernel for hw which just doesn't support it. But reformatting xrgb8888 to c8 is tricky at best. The uapis are all there for setting the palette, and C8 is a defined format even with atomic kms interface, but really there's not much userspace for it. In other words, it would work as well as current offb would, but that's at least that. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel