From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ovro.ovro.caltech.edu (ovro.ovro.caltech.edu [192.100.16.2]) by ozlabs.org (Postfix) with ESMTP id C480ADDEE8 for ; Fri, 26 Sep 2008 02:10:42 +1000 (EST) Message-ID: <48DBB402.8090402@ovro.caltech.edu> Date: Thu, 25 Sep 2008 08:53:38 -0700 From: David Hawkins MIME-Version: 1.0 To: Bruce_Leonard@selinc.com Subject: Re: How do I access nvRAM from user space? References: In-Reply-To: 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: , Hi Bruce, > Sorry for the dumb question, I just can figure out the right google search > to find what I'm trying to do. I'm running 2.6.27-rc4 on an mpc8347 with > a 32KiB nvSRAM (Cypress CY14B256L) on the local bus. We just want to be > able to access this memory from user space seperately from "main" memory. > We've got a process that needs to be able to remember info through power > cycles. Can anyone point me to an article or some code snippet that does > something like this so I can sink my teeth into it? Assuming your bootloader sets up the local bus access windows (physical address of the SRAM) and timing so that you can read/write to the SRAM, then once Linux boots, you should be able to just use /dev/mem as you would to access any other device registers at a specific address. Cheers, Dave