From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.semihalf.com (mail.semihalf.com [83.12.36.68]) by ozlabs.org (Postfix) with ESMTP id C4E90DDE4A for ; Sat, 21 Jul 2007 03:06:31 +1000 (EST) Message-ID: <46A0E6E7.3050309@semihalf.com> Date: Fri, 20 Jul 2007 18:46:31 +0200 From: Rafal Jaworowski MIME-Version: 1.0 To: lokowich Subject: Re: SDRAM failures on MPC5200B References: <46A0D76E.4030101@acdstar.com> In-Reply-To: <46A0D76E.4030101@acdstar.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , lokowich wrote: > We're working on bringing up a MPC5200B version of our original MPC5200 > board using U-Boot 1.1.4 configured for Icecube/Lite5200B. Other than > the CPU, the board is identical. The bootloader crashes just after > relocation to RAM, often with a Program Check Exception, typically a > memory corruption issue. I noticed failures at different stages after > relocation based on content, suggesting problems with upper SDRAM. If I > force the initram to 1/2 the determined size (64MB instead of 128MB), > then everything works well through kernel load and initialization. > We've added termination resistors to improve AD signals, to no avail. > Memory tests work fine too. Any help is appreciated. > Assuming your RAM chips are fine, are you setting the SDelay register (MBAR + 0x0190)? If not, this can lead to a strange hangs similar to the described. For details please see the current U-Boot's initdram() for icecube, and AN3221. Rafal