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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 981A5C433F5 for ; Mon, 24 Jan 2022 11:11:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237228AbiAXLLz (ORCPT ); Mon, 24 Jan 2022 06:11:55 -0500 Received: from mout.gmx.net ([212.227.17.22]:34625 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232330AbiAXLLx (ORCPT ); Mon, 24 Jan 2022 06:11:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1643022689; bh=vaZNWsffgiWonS7sv+nwaASVuPIvGSGB1y3edNq9IZY=; h=X-UI-Sender-Class:Date:Subject:To:Cc:References:From:In-Reply-To; b=RDHyhteYw11inncsGEVHi+veROG9TJqZIq6Z0cYRN2cKW6BA1i7ZgUv1eQD3wrted D14gxsfFT7RQAy98mVuEYZ3M7cxtrQPCREH4aoDi6BsulvAwT6HhhUhzonB436jvXL nMDerl86tVzSoAYIXJSJGqCWcaz9WNbe4BEzn6jU= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [192.168.20.60] ([92.116.165.96]) by mail.gmx.net (mrgmx104 [212.227.17.168]) with ESMTPSA (Nemesis) id 1N49lJ-1mCbA019FZ-0102SK; Mon, 24 Jan 2022 12:11:29 +0100 Message-ID: <64fd46cb-9746-3fd0-ec92-c64dba76875a@gmx.de> Date: Mon, 24 Jan 2022 12:10:19 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.3.0 Subject: Re: [PATCH 2/2] Revert "fbcon: Disable accelerated scrolling" Content-Language: en-US To: Gerd Hoffmann Cc: Thomas Zimmermann , Greg Kroah-Hartman , linux-fbdev@vger.kernel.org, Sven Schnelle , Linus Torvalds , Javier Martinez Canillas , Daniel Vetter , Ilia Mirkin , Tomi Valkeinen , dri-devel@lists.freedesktop.org, Jani Nikula , Pavel Machek , linux-kernel@vger.kernel.org, Geert Uytterhoeven , Sam Ravnborg , Claudio Suarez References: <20220119110839.33187-1-deller@gmx.de> <20220119110839.33187-3-deller@gmx.de> <6c000477-002b-d125-b945-2c4831bad8a5@gmx.de> <20220121072006.ylw2hdl7jbkbwnre@sirius.home.kraxel.org> From: Helge Deller In-Reply-To: <20220121072006.ylw2hdl7jbkbwnre@sirius.home.kraxel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:cQ2CXc5PlbnzvHYLeF6mCJSXPAtiiC9YrH66NvSERb+BiDbK1v9 P7yUcMSr3eAdFeElKrC/xIw6gFIsFQS+gBOXBuEE2ziyCNRTRiVmvnNWj7Z5pOYv4J9Tax5 4eSRI8ilt1JwpYdIikIUWzPu9XjGSQfhR7pvjfclo0M3EmXnPBS9oSGSqAYtP+XLklC4cX3 /6p6gpoxNYBD/TL95nOJg== X-UI-Out-Filterresults: notjunk:1;V03:K0:XvILxYcelpA=:O2OubiAtE69DCEvdExI5WC fdNlOP/VgZRKZhbZ/5AnwvP6yKgvQkzcjmkyYI4aDUvmwDL/1iVo9s+8GWrBskPza7F10ldwS v2R9f16c1nCPFroOOlu14KVNkPFNQvZe0a3TB+U18bj3JEAw5E++OJSBz9uatSOf0UqjYDjBq kzL/dq+tOYyYt07Qhda81wZkszpNJpVy07C/pMiyPfce2Zxivz192mW6f+55WWQ007lm1KDJJ 05tIATNvsSCNlUCaVNJ2NjB3exfsJBVwQhkWAVyMjShZwHaHBAP04SdoVI0UOQrp7hG4XjFFR d5AYtkp1uLoJXAJPJ4GLK6t1ACBH5hxSz9cgfH5X2UxheC2I1f3l84eqISxm6Fdzm0pyDnjru uesumOeMVefpY5fTkztAPvNcmkh9rxZiRyzTFLLodFMJRY0FHr1KpTEZ3KO0m8GkDMYnTtZrZ 9GhV1tnl72FA1mdGHZ2lzKkBwChjuIZw3HkpCLCg9+BOuqEgCV1+6R7auHejdVG6CY2GzmP/s v9kYGJxtpNiqmQ6kGedAGgHeRMPDIm4yuwdPa0WamUkxsaBONflJmuOq7Ke24TV/cVWUEra2G NnL1SwP683e5islyrVashAdhm+zS+d37XkbGnftuOIvl6KHApET0IVDL0/dMyPMN/Y9AkxKvd lJofOoECF5zNirmVo8TUUBlq/0ejqSGcDKlnoeIV2tOShvSgz2lc6Qvb73ye7+aFPRKkKtnTw awl3EU6gBVOLWgiE/tHpwSC8G99L+kP4zrkq3xcSAWdCxZRVtxm81WXUpEIgIDeDtL1zaN12N oKhPMgiSOEKHoJvGW64hZaks3RIKsIAWSdEt0TG1Y/eWFzl+UZaYp611zm1f7ryBDviK4iGCT JtesXkLCFCtpxRnhRtIuzCzkiMpMvOxxNJ+I55fLgmEb196zJf3RvrtzYYCGdLv2TRlYxag4B nP1Ga12edfsWBYEVb1gk6m8Vcl6QszgmoVEQ1HuNy8QyHZY8RnspgENwhcpSzv5F9bkBG2X3/ 7WjXpwVseDBG3KnWSphbpWSDbxE1VnniM/GumTKPWBtcrwNDhvL+imJMz4Ue3KMdOIMEjwZ09 tDJ89YqZHe/38k= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/21/22 08:20, Gerd Hoffmann wrote: >>> So if this really has to come back then I think the pragmatic approach= is >>> to do it behind a CONFIG_FBCON_ACCEL, default n, and with a huge warni= ng >>> that enabling that shouldn't be done for any distro which only enables >>> firmware and drm fbdev drivers. >> >> Thanks for coming back on this, but quite frankly I don't understand >> that request. How should that warning look like, something along: >> "BE WARNED: The framebuffer text console on your non-DRM supported >> graphic card will then run faster and smoother if you enable this optio= n." >> That doesn't make sense. People and distros would want to enable that. > > Nope. Most distros want disable fbdev drivers rather sooner than later. > The fbdev drivers enabled in the fedora kernel today: > > CONFIG_FB_VGA16=3Dm > CONFIG_FB_VESA=3Dy > CONFIG_FB_EFI=3Dy > CONFIG_FB_SSD1307=3Dm > > CONFIG_FB_VESA + CONFIG_FB_EFI will go away soon, with simpledrm taking > over their role. That's Ok. Nevertheless, some distros and platforms will still need fbdev drivers for various reasons. >> And if a distro *just* has firmware and drm fbdev drivers enabled, >> none of the non-DRM graphic cards would be loaded anyway and this code >> wouldn't be executed anyway. > > Yes, exactly. That's why there is no point in compiling that code. As long as you have a graphic card which is not supported by DRM you still= need it. Here is my proposed way forward: a) I will resend the patches which reverts the remove-fbcon-hardware-scoll= ing patches to the mailing lists. I'll adjust the stable tags and update the commit= messages. b) Then after some days I'll include it in the fbdev for-next git branch. = That way it's included in the various build & test chains. c) If everything is working well, I'll push that change during the next me= rge window for kernel 5.18. If problems arise we will need to discuss. While the patches are in the fbdev git tree we should decide how to exclud= e code which is not needed for DRM. What about this proposal: a) adding a Kconfig option like: CONFIG_FB_DRIVERS - enable if you need the fbdev drivers. For DRM-only = this should be disabled. b) Add to every native fbdev driver a "depends on FB_DRIVERS" in the Kconf= ig files. c) That way we can use "#if defined(CONFIG_FB_DRIVERS).." to exclude code = in fbcon which isn't needed by DRM. Thoughts? Helge