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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 6A279C433FE for ; Wed, 16 Nov 2022 16:09:44 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A61EB10E4CD; Wed, 16 Nov 2022 16:09:30 +0000 (UTC) Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8C0AB10E4CD for ; Wed, 16 Nov 2022 16:09:22 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 39AA61F956; Wed, 16 Nov 2022 16:09:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1668614961; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6hgtxI+2HsmrlPFC80G0bZQ/s9HsOj9OF44Gk56AZwA=; b=IkQpaKYZ7KDolvPnrncc55qoGdhaXqiNKkzz4MPE/ycEpLh9xwicFGLRA/XjCWhm9UC/jp iTnvVSl+4OdKjt2NZnZrhnILKPb4RvfEKbZcBdCE5/0azIWi1u9BU7fiI/vRNshoOlOWji tEO6WD2xeHzmCmRe7BjUdCm45JsfVY0= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1668614961; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6hgtxI+2HsmrlPFC80G0bZQ/s9HsOj9OF44Gk56AZwA=; b=OS1QIQujCaRqoNpgpGcWm9Ha8Sw3PRl+qBviL/4HvcUM3cshQykdBUqLj86rgMqNJWKpjH O2fSR1E7KbGUK4DA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id E831D13AC7; Wed, 16 Nov 2022 16:09:20 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 6MXdNzALdWP/fwAAMHmgww (envelope-from ); Wed, 16 Nov 2022 16:09:20 +0000 From: Thomas Zimmermann To: daniel@ffwll.ch, airlied@gmail.com, mripard@kernel.org, maarten.lankhorst@linux.intel.com, xinliang.liu@linaro.org, tiantao6@hisilicon.com, jstultz@google.com, kong.kongxinwei@hisilicon.com, puck.chen@hisilicon.com, paul.kocialkowski@bootlin.com, javierm@redhat.com, airlied@redhat.com, kraxel@redhat.com Subject: [PATCH 7/7] drm/fb-helper: Don't use the preferred depth for the BPP default Date: Wed, 16 Nov 2022 17:09:17 +0100 Message-Id: <20221116160917.26342-8-tzimmermann@suse.de> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221116160917.26342-1-tzimmermann@suse.de> References: <20221116160917.26342-1-tzimmermann@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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: Thomas Zimmermann , dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" If no preferred value for bits-per-pixel has been given, fall back to 32. Never use the preferred depth. The color depth is the number of color/alpha bits per pixel, while bpp is the overall number of bits in most cases. Most noteworthy, XRGB8888 has a depth of 24 and a bpp value of 32. Using depth for bpp would make the value 24 as well and format selection in fbdev helpers fails. Unfortunately XRGB8888 is the most common format and the old heuristic therefore fails for most of the drivers (unless they implement the 24-bit RGB888 format). Picking a bpp of 32 will lateron result in a default depth of 24 and the format XRGB8888. As XRGB8888 is the default format for most of the current and legacy graphics stack, all drivers must support it. So it is the safe choice. Signed-off-by: Thomas Zimmermann --- drivers/gpu/drm/drm_fbdev_generic.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/drm_fbdev_generic.c b/drivers/gpu/drm/drm_fbdev_generic.c index ab86956692795..0a4c160e0e58a 100644 --- a/drivers/gpu/drm/drm_fbdev_generic.c +++ b/drivers/gpu/drm/drm_fbdev_generic.c @@ -431,7 +431,6 @@ static const struct drm_client_funcs drm_fbdev_client_funcs = { * drm_fbdev_generic_setup() - Setup generic fbdev emulation * @dev: DRM device * @preferred_bpp: Preferred bits per pixel for the device. - * @dev->mode_config.preferred_depth is used if this is zero. * * This function sets up generic fbdev emulation for drivers that supports * dumb buffers with a virtual address and that can be mmap'ed. @@ -475,12 +474,16 @@ void drm_fbdev_generic_setup(struct drm_device *dev, } /* - * FIXME: This mixes up depth with bpp, which results in a glorious - * mess, resulting in some drivers picking wrong fbdev defaults and - * others wrong preferred_depth defaults. + * Pick a preferred bpp of 32 if no value has been given. This + * will select XRGB8888 for the framebuffer formats. All drivers + * have to support XRGB8888 for backwards compatibility with legacy + * userspace, so it's the safe choice here. + * + * TODO: Replace struct drm_mode_config.preferred_depth and this + * bpp value with a preferred format that is given as struct + * drm_format_info. Then derive all other values from the + * format. */ - if (!preferred_bpp) - preferred_bpp = dev->mode_config.preferred_depth; if (!preferred_bpp) preferred_bpp = 32; fb_helper->preferred_bpp = preferred_bpp; -- 2.38.1