From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from webbox1416.server-home.net ([77.236.96.61]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1bDUGy-0005I7-MV for barebox@lists.infradead.org; Thu, 16 Jun 2016 10:11:42 +0000 Received: from imapserver.systec-electronic.com (unknown [212.185.67.146]) by webbox1416.server-home.net (Postfix) with ESMTPA id 9F3AA27A617 for ; Thu, 16 Jun 2016 12:11:16 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by imapserver.systec-electronic.com (Postfix) with ESMTP id 7E20EDA08E5 for ; Thu, 16 Jun 2016 12:11:16 +0200 (CEST) Received: from imapserver.systec-electronic.com ([127.0.0.1]) by localhost (imapserver.systec-electronic.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id XK5ZdINvrRQO for ; Thu, 16 Jun 2016 12:11:10 +0200 (CEST) Received: from [192.168.10.177] (ws-krueger.systec.local [192.168.10.177]) by imapserver.systec-electronic.com (Postfix) with ESMTP id C11BADA0A56 for ; Thu, 16 Jun 2016 12:11:10 +0200 (CEST) From: =?UTF-8?Q?Daniel_Kr=c3=bcger?= Message-ID: <57627B3E.5020100@systec-electronic.com> Date: Thu, 16 Jun 2016 12:11:10 +0200 MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: ARM memory layout To: barebox@lists.infradead.org Hello, during the porting of barebox to a new i.MX35 board I stumbled over some crazy things with the memory layout. The comments in file arch/arm/cpu/entry.c seem to be wrong or at least misleading. We configured barebox as non-relocatable image. So I think the configured TEXT_BASE is very important. I use the following configuration with 128 MB RAM: CONFIG_TEXT_BASE=0x87000000 CONFIG_STACK_SIZE=0x100000 CONFIG_MALLOC_SIZE=0xd00000 The stack is configured very large in this project, because of other reason. I get the following memory layout: 0x87ffffff top of RAM | free-space (see arm_mem_stack() in | arch/arm/include/asm/barebox-arm.h) 0x87ff0000 start of 64 kB free-space (vector table) 0x87feffff top of stack | 0x87ef0000 start of 1 MB reserved stack space 0x87eeffff | 16 kB early translation table 0x87eec000 early TTB (translation table base) 0x87eebfff malloc end | 13 MB malloc space 0x871ec000 malloc start | some small free space | barebox binary 0x87000000 TEXT_BASE This does not comply to the comment in the above mentioned source file. There the malloc space and the vector table are missing. I would expect some check in the source code, when TEXT_BASE is too high or barebox binary is too large, so they collide with malloc space or stack. By reverse engineering the detailed memory layout above, I discovered that in another project the TEXT_BASE falls within the malloc space. How does is run on other ARM boards? Are they all running with CONFIG_RELOCATABLE=Y? Best regards, Daniel -- SYS TEC electronic GmbH Am Windrad 2 08468 Heinsdorfergrund Telefon : +49 (0) 3765 38600-0 Fax : +49 (0) 3765 38600-4100 Email : daniel.krueger@systec-electronic.com Website : http://www.systec-electronic.com Managing Directors : Dipl.-Phys. Siegmar Schmidt, Dipl. Ing. (FH) Armin von Collrepp Commercial registry : Amtsgericht Chemnitz, HRB 28082 USt.-Id Nr. : DE150534010 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox