From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 208.177.141.226.ptr.us.xo.net ([208.177.141.226] helo=ash.lnxi.com) by pentafluge.infradead.org with smtp (Exim 4.30 #5 (Red Hat Linux)) id 1AlrtE-0002l5-HD for linux-mtd@lists.infradead.org; Wed, 28 Jan 2004 15:46:04 +0000 To: Shawn Jin References: <20040128034734.77883.qmail@web20725.mail.yahoo.com> From: ebiederman@lnxi.com (Eric W. Biederman) Date: 28 Jan 2004 08:48:18 -0700 In-Reply-To: <20040128034734.77883.qmail@web20725.mail.yahoo.com> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: "Eric W. Biederman" cc: linux-mtd@lists.infradead.org Subject: Re: 64 bit bus access on a customed MPC8245 board List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Shawn Jin writes: > Hi, > > I'm working on a customed MPC8245 board with flash > chip Am29LV320 and trying to enable MTD driver > support. The MPC8245 is an embedded ppc processor. ?? I looked and I can't find documentation for that chip. Is it an atmel one? Chips with similar part numbers are 8 bit flash. Atmel does make a few 16bit flash parts. And I don't know if Atmel does cfi? You may need jedec_probe. > The configuration is 32 bit bus width in each chip > with 2 chips interleaved. So CONFIG_MTD_CFI_B8 and > CONFIG_MTD_CFI_I2 are defined. Ok so you have configured it for 2 8bit chips that are interleaved to form a 16bit path. > MPC8245 requires the following memory mapping: > bank 0: 0xFF800000 - 0xFFFFFFFF > bank 1: 0xFF000000 - 0xFF7FFFFF > > I noticed that FPU must be enabled for 64-bit > read/write from/to flash. But that is not even interesting if you are only 16bits wide. > I use read64() and write64() functions in the > attachment, which are copied from sbc8240.c. However > no chip can be found. Any suggestions? Thank you very > much. I suggest you focus on read16()/write16(). Eric