From patchwork Tue Feb 15 16:52:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 542866 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 336B0C433EF for ; Tue, 15 Feb 2022 16:52:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237285AbiBOQwp (ORCPT ); Tue, 15 Feb 2022 11:52:45 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:59944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233641AbiBOQwo (ORCPT ); Tue, 15 Feb 2022 11:52:44 -0500 Received: from albert.telenet-ops.be (albert.telenet-ops.be [IPv6:2a02:1800:110:4::f00:1a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 696049BAF5 for ; Tue, 15 Feb 2022 08:52:33 -0800 (PST) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed40:7534:e0be:5adf:2691]) by albert.telenet-ops.be with bizsmtp id vUsV2600718GbK106UsVLq; Tue, 15 Feb 2022 17:52:31 +0100 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nK140-000tUj-RY; Tue, 15 Feb 2022 17:52:28 +0100 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1nK13z-00BURL-Tk; Tue, 15 Feb 2022 17:52:27 +0100 From: Geert Uytterhoeven To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Helge Deller , Javier Martinez Canillas Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-m68k@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH 0/8] drm: Add support for low-color frame buffer formats Date: Tue, 15 Feb 2022 17:52:18 +0100 Message-Id: <20220215165226.2738568-1-geert@linux-m68k.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org Hi all, A long outstanding issue with the DRM subsystem has been the lack of support for low-color displays, as used typically on older desktop systems and small embedded displays. This patch series adds support for color-indexed frame buffer formats with 2, 4, and 16 colors. It has been tested on ARAnyM using a work-in-progress Atari DRM driver, with text console operation and fbtest. Overview: - Patches 1 and 2 give a working system, albeit with a too large pitch (line length), - Patches 3 and 4 reduce memory consumption by correcting the pitch in case bpp < 8, - Patches 5 and 6 are untested, but may become useful with DRM userspace, - Patches 7 and 8 add more fourcc codes for grayscale and monochrome frame buffer formats, which may be useful for e.g. the ssd130x and repaper drivers. Notes: - I haven't looked yet into making modetest draw a correct image. - As this was used on emulated hardware only, and I do not have Atari hardware, I do not have performance figures to compare with fbdev. I hope to do proper measuring with an Amiga DRM driver, eventually. Thanks for your comments! Geert Uytterhoeven (8): drm/fourcc: Add DRM_FORMAT_C[124] drm/fb-helper: Add support for DRM_FORMAT_C[124] drm/fourcc: Add drm_format_info_bpp() helper drm/client: Use actual bpp when allocating frame buffers drm/framebuffer: Use actual bpp for DRM_IOCTL_MODE_GETFB drm/gem-fb-helper: Use actual bpp for size calculations drm/fourcc: Add DRM_FORMAT_R[124] drm/fourcc: Add DRM_FORMAT_D1 drivers/gpu/drm/drm_client.c | 4 +- drivers/gpu/drm/drm_fb_helper.c | 120 ++++++++++++++----- drivers/gpu/drm/drm_fourcc.c | 45 +++++++ drivers/gpu/drm/drm_framebuffer.c | 2 +- drivers/gpu/drm/drm_gem_framebuffer_helper.c | 12 +- include/drm/drm_fourcc.h | 1 + include/uapi/drm/drm_fourcc.h | 15 +++ 7 files changed, 160 insertions(+), 39 deletions(-) Acked-by: Thomas Zimmermann