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 822BFCD8CA4 for ; Tue, 9 Jun 2026 09:56:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E86F610E1F1; Tue, 9 Jun 2026 09:56:41 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="rI2a0MbT"; dkim-atps=neutral X-Greylist: delayed 590 seconds by postgrey-1.36 at gabe; Tue, 09 Jun 2026 09:56:39 UTC Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) by gabe.freedesktop.org (Postfix) with ESMTPS id 799FA10E1F1 for ; Tue, 9 Jun 2026 09:56:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: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=Sw1opRUXcAw/1NhWQ+DjHthGw6A5mSCQCWdmv0WppA8=; b=rI2a0MbTWMwB/3rZkDrP74q/UO i3TT9fSM3f58ih8ydJ6Ch4Z18EcAsceHJaRcSitWe9Huvmzcnzmhcpm+YsXeKjhf7jjOVUePegtCr hbnvvyYlpN/GDs+VpIYaSSfh+hlbgM1IW69ApQOscaGfruBO8EGhKAgjIc+BRNpkT4kr+kY7wrgEj T5dvAEGruxhqDBVlQ1m7bu5WLPETHgXLi4lplfFNEnDczmEbY5gFCHr7tB1frRf2TYDTNreGinGbC gYfsjpvi6A0kIJuLga6bad/k1qJzZnHrx8ETlk37HTKDN55Koe7D1GWHbdDpp5aAWW/4QQqgNgsQT CQMzCRmw==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:43128) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wWt2j-0000000063F-3tfB; Tue, 09 Jun 2026 10:46:46 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.98.2) (envelope-from ) id 1wWt2g-000000002ua-3S77; Tue, 09 Jun 2026 10:46:42 +0100 Date: Tue, 9 Jun 2026 10:46:42 +0100 From: "Russell King (Oracle)" To: Helge Deller Cc: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, Ethan Nelson-Moore , Thomas Zimmermann , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] fbdev/arm: Export acorndata_8x8 font symbol for bootloader Message-ID: References: <20260609091056.265794-1-deller@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260609091056.265794-1-deller@gmx.de> 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" On Tue, Jun 09, 2026 at 11:10:56AM +0200, Helge Deller wrote: > The text display code used in the Risc PC kernel image decompression > code uses arch/arm/boot/compressed/font.c, which includes > lib/fonts/font_acorn_8x8.c, which further includes . > > Since commit 97df8960240a ("lib/fonts: Provide helpers for calculating > glyph pitch and size") contains inline functions that > require __do_div64, which is not linked into the ARM kernel > decompressor. This makes Risc PC zImages fail to build. > > Resolve this issue by defining the BOOTLOADER symbol and use it to avoid > a static declaration of the acorndata_8x8 symbol. That way it can be > referenced by the arm bootloader, and other static math functions and > symbols (like __do_div64) stay static and don't get unneccesary included > in the ARM kernel bootloader decompressor object file. The decompressor font support has actually been broken since: commit 6735b4632def0640dbdf4eb9f99816aca18c4f16 Author: Peilin Ye Date: Thu Sep 24 09:42:22 2020 -0400 Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts which added extra data to the beginning of the array of font information: ENTRY(ll_write_char) stmfd sp!, {r4 - r7, lr} ... /* * calculate offset into character table */ mov r1, r1, lsl #3 r1 is the character, this multiplies the character value by 8. adr ip, LC0 ldmia ip, {r3, r4, r5, r6, lr} sub ip, ip, r3 add r6, r6, ip in conjunction with the data table: LC0: .word LC0 .word bytes_per_char_h .word video_size_row .word acorndata_8x8 .word con_charconvtable results in r6 pointing at acorndata_8x8. We then index this using the modified character value above: orr r1, r1, #7 ldrb r7, [r6, r1] This breaks if extra data is added to the start, and thus has been broken since the above commit. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!