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 C7315C48BC3 for ; Wed, 21 Feb 2024 11:07:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 623DD10E530; Wed, 21 Feb 2024 11:07:45 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=haloniitty.fi header.i=@haloniitty.fi header.b="ODwtR1Od"; dkim-atps=neutral Received: from whm50.louhi.net (whm50.louhi.net [77.240.19.51]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6B2CD10E530 for ; Wed, 21 Feb 2024 11:07:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=haloniitty.fi; s=default; h=Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=8MEbSgLr14pQ77N6lKxlvIG7N5j9vcdLPNFkBy0PnSg=; b=ODwtR1OdWYMOWcV5BlKgbOZWQy PawgpD4VJe6p3T/yRonxr2Iz867Qu/bYYc3ex1dJfeSuiBKsF8GrCagMCExdC3Z/c6PibJgg0jNJh JOKg1LPz9GkZgZENCs2XAMBlOgkB2i6PSsOq1bPzTPLzgFPCsVuFk9ZfUKLJnYETcNsDMccxjL5dh e23cA8Nz2l5//bGsPiS2yzfKa3VKpFTk+g6tI3Pt1G6CU8XKbsx8lXAEYyO5PZVKetQoa4oW/+3Ta wTfnHMBmrYto/9t0YiAAZjFxT40Io7QTgLxH3o/yXQMBZHqhaAB7U7Z57U3h7T95nfcN4uOLconSf jWSIzDoQ==; Received: from [194.136.85.206] (port=35802 helo=eldfell) by whm50.louhi.net with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96.2) (envelope-from ) id 1rckRw-0003mB-0l; Wed, 21 Feb 2024 13:07:41 +0200 Date: Wed, 21 Feb 2024 13:07:31 +0200 From: Pekka Paalanen To: Maxime Ripard Cc: Daniel Vetter , David Airlie , Maarten Lankhorst , Thomas Zimmermann , dri-devel@lists.freedesktop.org, Dave Stevenson , Jani Nikula Subject: Re: [PATCH v2] drm/edid/firmware: Remove built-in EDIDs Message-ID: <20240221130731.70664a22@eldfell> In-Reply-To: <20240221092636.691701-1-mripard@kernel.org> References: <20240221092636.691701-1-mripard@kernel.org> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/PA+gXVlpl8WS4d=3AGxOblz"; protocol="application/pgp-signature"; micalg=pgp-sha256 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - whm50.louhi.net X-AntiAbuse: Original Domain - lists.freedesktop.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - haloniitty.fi X-Get-Message-Sender-Via: whm50.louhi.net: authenticated_id: pekka.paalanen@haloniitty.fi X-Authenticated-Sender: whm50.louhi.net: pekka.paalanen@haloniitty.fi X-Source: X-Source-Args: X-Source-Dir: 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" --Sig_/PA+gXVlpl8WS4d=3AGxOblz Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Wed, 21 Feb 2024 10:26:36 +0100 Maxime Ripard wrote: > The EDID firmware loading mechanism introduced a few built-in EDIDs that > could be forced on any connector, bypassing the EDIDs it exposes. >=20 > While convenient, this limited set of EDIDs doesn't take into account > the connector type, and we can end up with an EDID that is completely > invalid for a given connector. >=20 > For example, the edid/800x600.bin file matches the following EDID: ... >=20 > So, an analog monitor EDID. However, if the connector was an HDMI > monitor for example, it breaks the HDMI specification that requires, > among other things, a digital display, the VIC 1 mode and an HDMI Forum > Vendor Specific Data Block in an CTA-861 extension. >=20 > We thus end up with a completely invalid EDID, which thus might confuse > HDMI-related code that could parse it. >=20 > After some discussions on IRC, we identified mainly two ways to fix > this: >=20 > - We can either create more EDIDs for each connector type to provide > a built-in EDID that matches the resolution passed in the name, and > still be a sensible EDID for that connector type; >=20 > - Or we can just prevent the EDID to be exposed to userspace if it's > built-in. >=20 > Or possibly both. >=20 > However, the conclusion was that maybe we just don't need the built-in > EDIDs at all and we should just get rid of them. So here we are. Sounds good to me. Acked-by: Pekka Paalanen If it turns out that these cannot be completely removed, then yet another option would to refuse to use these on digital connectors. Thanks, pq >=20 > Acked-by: Thomas Zimmermann > Signed-off-by: Maxime Ripard > --- > Documentation/admin-guide/edid.rst | 35 +-- > .../admin-guide/kernel-parameters.txt | 14 +- > drivers/gpu/drm/drm_edid_load.c | 160 +--------- > tools/edid/1024x768.S | 43 --- > tools/edid/1280x1024.S | 43 --- > tools/edid/1600x1200.S | 43 --- > tools/edid/1680x1050.S | 43 --- > tools/edid/1920x1080.S | 43 --- > tools/edid/800x600.S | 40 --- > tools/edid/Makefile | 37 --- > tools/edid/edid.S | 274 ------------------ > tools/edid/hex | 1 - > 12 files changed, 18 insertions(+), 758 deletions(-) > delete mode 100644 tools/edid/1024x768.S > delete mode 100644 tools/edid/1280x1024.S > delete mode 100644 tools/edid/1600x1200.S > delete mode 100644 tools/edid/1680x1050.S > delete mode 100644 tools/edid/1920x1080.S > delete mode 100644 tools/edid/800x600.S > delete mode 100644 tools/edid/Makefile > delete mode 100644 tools/edid/edid.S > delete mode 100644 tools/edid/hex --Sig_/PA+gXVlpl8WS4d=3AGxOblz Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEJQjwWQChkWOYOIONI1/ltBGqqqcFAmXV2XMACgkQI1/ltBGq qqcFqhAAq0Sv3VYbk/MHDnOtYu+JccmQjxVvFWxUNm1C+AGzjjrL2tJ/f655PNGC b4dwO+z1ItXgcH7ORgt4JkZRu8WOlWj15J/BIKgeXqnqvj3ZSr7MMp0A0yBev5p3 jPzwPF5/ttym/9ZvJnhc/hx25GgvXHzwawYTH+8XCyOKU9WCHXdxJOyzFqOt9giQ otQ4mpgQvGGmDyUUWgeymTcxfc+8TAQ0mdk86T+5TI51WcrO0UxQ8ihmtYgWV2CE UhYPAbSV4fvDa7Ogf5bXOxQUOxhd+KJEEd033C2lgwhZUtaIxN6pk1wInqqPJtjg dsASMgyjSACwocFCiTYSEeZdplflhUy2KXI996ZoN77sD268RFxsmYQlpppfGIwA DlZ4xBE+YT55ysfONQQ0R7xmhfsrFt5UlAmG0AldRZwARq738dWcvYJ/rBv+VLY+ C5AAFeCozDUSK07AlSOeplnBdBdHyli2mo4kBO33SRBGJ/u4i04N9+oqjugLgOx0 dyogJOcqRcAWzHVCC/CT29ht6afoIfqIVVuDJPl4PawQOefyeAA79djgAY81/nII PkZwgVRJOAZAXR/GCnQdReW7H64AfZeUcAjvh9C56wuDdroQhj7Kz89TZApEDriP G5ixQxmeX2pfJUj2Jt7khZWQsGFe88d3oyl1d6lgF4UZXl2p44o= =MmZA -----END PGP SIGNATURE----- --Sig_/PA+gXVlpl8WS4d=3AGxOblz--