From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.7 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 20F7D7D918 for ; Thu, 17 Oct 2019 07:47:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387489AbfJQHrK (ORCPT ); Thu, 17 Oct 2019 03:47:10 -0400 Received: from mx2.suse.de ([195.135.220.15]:48244 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2387930AbfJQHrK (ORCPT ); Thu, 17 Oct 2019 03:47:10 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 1CB2CB591; Thu, 17 Oct 2019 07:47:09 +0000 (UTC) From: Thomas Zimmermann To: daniel@ffwll.ch Cc: corbet@lwn.net, dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, Thomas Zimmermann Subject: [PATCH v3 1/1] drm: Add TODO item for fbdev driver conversion Date: Thu, 17 Oct 2019 09:47:05 +0200 Message-Id: <20191017074705.9140-2-tzimmermann@suse.de> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191017074705.9140-1-tzimmermann@suse.de> References: <20191017074705.9140-1-tzimmermann@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org The DRM TODO list now contains an entry for converting fbdev drivers over to DRM. Signed-off-by: Thomas Zimmermann --- Documentation/gpu/todo.rst | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 79785559d711..23b3a67794ba 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -462,3 +462,30 @@ Contact: Sam Ravnborg Outside DRM =========== + +Convert fbdev drivers to DRM +---------------------------- + +There are plenty of fbdev drivers for older hardware. Some hwardware has +become obsolete, but some still provides good(-enough) framebuffers. The +drivers that are still useful should be converted to DRM and afterwards +removed from fbdev. + +Very simple fbdev drivers can best be converted by starting with a new +DRM driver. Simple KMS helpers and SHMEM should be able to handle any +existing hardware. The new driver's call-back functions are filled from +existing fbdev code. + +More complex fbdev drivers can be refactored step-by-step into a DRM +driver with the help of the DRM fbconv helpers. [1] These helpers provide +the transition layer between the DRM core infrastructure and the fbdev +driver interface. Create a new DRM driver on top of the fbconv helpers, +copy over the fbdev driver, and hook it up to the DRM code. Examples for +several fbdev drivers are available at [1] and a tutorial of this process +available at [2]. The result is a primitive DRM driver that can run X11 +and Weston. + + - [1] https://gitlab.freedesktop.org/tzimmermann/linux/tree/fbconv + - [2] https://gitlab.freedesktop.org/tzimmermann/linux/blob/fbconv/drivers/gpu/drm/drm_fbconv_helper.c + +Contact: Thomas Zimmermann -- 2.23.0