From patchwork Tue Jun 21 05:09:13 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Pitre X-Patchwork-Id: 899762 Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by demeter1.kernel.org (8.14.4/8.14.4) with ESMTP id p5L5AGG4002639 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Tue, 21 Jun 2011 05:10:37 GMT Received: from canuck.infradead.org ([2001:4978:20e::1]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1QYtDy-0000nr-3l; Tue, 21 Jun 2011 05:10:06 +0000 Received: from localhost ([127.0.0.1] helo=canuck.infradead.org) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QYtDx-0006JI-EX; Tue, 21 Jun 2011 05:10:05 +0000 Received: from relais.videotron.ca ([24.201.245.36]) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1QYtDO-0006CH-Cu for linux-arm-kernel@lists.infradead.org; Tue, 21 Jun 2011 05:09:35 +0000 Received: from xanadu.home ([66.130.28.92]) by vl-mh-mrz25.ip.videotron.ca (Sun Java(tm) System Messaging Server 6.3-8.01 (built Dec 16 2008; 32bit)) with ESMTP id <0LN40037RJJWC1C0@vl-mh-mrz25.ip.videotron.ca> for linux-arm-kernel@lists.infradead.org; Tue, 21 Jun 2011 01:07:09 -0400 (EDT) From: Nicolas Pitre To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 2/4] ARM: zImage: Allow the appending of a device tree binary Date: Tue, 21 Jun 2011 01:09:13 -0400 Message-id: <1308632955-11070-3-git-send-email-nico@fluxnic.net> X-Mailer: git-send-email 1.7.4 In-reply-to: <1308632955-11070-1-git-send-email-nico@fluxnic.net> References: <1308632955-11070-1-git-send-email-nico@fluxnic.net> X-CRM114-Version: 20090807-BlameThorstenAndJenny ( TRE 0.7.6 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20110621_010930_688824_D524485A X-CRM114-Status: GOOD ( 33.18 ) X-Spam-Score: 0.0 (/) X-Spam-Report: SpamAssassin version 3.3.1 on canuck.infradead.org summary: Content analysis details: (0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, low trust [24.201.245.36 listed in list.dnswl.org] Cc: John Bonesio , Tony Lindgren , David Brown , devicetree-discuss@lists.ozlabs.org, Grant Likely X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Tue, 21 Jun 2011 05:10:37 +0000 (UTC) From: John Bonesio This patch provides the ability to boot using a device tree that is appended to the raw binary zImage (e.g. cat zImage .dtb > zImage_w_dtb). Signed-off-by: John Bonesio [nico: adjusted to latest zImage changes plus additional cleanups] Signed-off-by: Nicolas Pitre Acked-by: Grant Likely Acked-by: Tony Lindgren --- arch/arm/Kconfig | 8 ++++ arch/arm/boot/compressed/head.S | 70 +++++++++++++++++++++++++++++++++++++-- 2 files changed, 75 insertions(+), 3 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 9adc278..66b7d1e 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1727,6 +1727,14 @@ config ZBOOT_ROM_MMCIF which in turn loads the rest the kernel image to RAM using the MMCIF hardware block. +config ARM_APPENDED_DTB + bool "Use appended device tree blob to zImage" + depends on OF && !ZBOOT_ROM + help + With this option, the boot code will look for a device tree binary + (dtb) appended to zImage + (e.g. cat zImage .dtb > zImage_w_dtb). + config CMDLINE string "Default kernel command string" default "" diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index f9da419..b791b5e 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -216,6 +216,59 @@ restart: adr r0, LC0 mov r10, r6 #endif + mov r5, #0 @ init dtb size to 0 +#ifdef CONFIG_ARM_APPENDED_DTB +/* + * r0 = delta + * r2 = BSS start + * r3 = BSS end + * r4 = final kernel address + * r5 = appended dtb size (still unknown) + * r6 = _edata + * r7 = architecture ID + * r8 = atags/device tree pointer + * r9 = size of decompressed image + * r10 = end of this image, including bss/stack/malloc space if non XIP + * r11 = GOT start + * r12 = GOT end + * sp = stack pointer + * + * if there are device trees (dtb) appended to zImage, advance r10 so that the + * dtb data will get relocated along with the kernel if necessary. + */ + + ldr lr, [r6, #0] +#ifndef __ARMEB__ + ldr r1, =0xedfe0dd0 @ sig is 0xd00dfeed big endian +#else + ldr r1, =0xd00dfeed +#endif + cmp lr, r1 + bne dtb_check_done @ not found + + mov r8, r6 @ use the appended device tree + + /* Get the dtb's size */ + ldr r5, [r6, #4] +#ifndef __ARMEB__ + /* convert r5 (dtb size) to little endian */ + eor r1, r5, r5, ror #16 + bic r1, r1, #0x00ff0000 + mov r5, r5, ror #8 + eor r5, r5, r1, lsr #8 +#endif + + /* preserve 64-bit alignment */ + add r5, r5, #7 + bic r5, r5, #7 + + /* relocate some pointers past the appended dtb */ + add r6, r6, r5 + add r10, r10, r5 + add sp, sp, r5 +dtb_check_done: +#endif + /* * Check to see if we will overwrite ourselves. * r4 = final kernel address @@ -285,14 +338,16 @@ wont_overwrite: * r2 = BSS start * r3 = BSS end * r4 = kernel execution address + * r5 = appended dtb size (0 if not present) * r7 = architecture ID * r8 = atags pointer * r11 = GOT start * r12 = GOT end * sp = stack pointer */ - teq r0, #0 + orrs r1, r0, r5 beq not_relocated + add r11, r11, r0 add r12, r12, r0 @@ -307,12 +362,21 @@ wont_overwrite: /* * Relocate all entries in the GOT table. + * Bump bss entries to _edata + dtb size */ 1: ldr r1, [r11, #0] @ relocate entries in the GOT - add r1, r1, r0 @ table. This fixes up the - str r1, [r11], #4 @ C references. + add r1, r1, r0 @ This fixes up C references + cmp r1, r2 @ if entry >= bss_start && + cmphs r3, r1 @ bss_end > entry + addhi r1, r1, r5 @ entry += dtb size + str r1, [r11], #4 @ next entry cmp r11, r12 blo 1b + + /* bump our bss pointers too */ + add r2, r2, r5 + add r3, r3, r5 + #else /*