From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <3CE0F23E.2FADEABB@etx.ericsson.se> Date: Tue, 14 May 2002 13:17:18 +0200 From: Kenneth Johansson MIME-Version: 1.0 To: Sangmoon Kim Cc: linuxppc-embedded@lists.linuxppc.org Subject: Re: File System on 64-bit-bus-width Flash memory References: <000b01c1fb37$50751cf0$1a11efcb@industrialDiv.hanasys.co.kr> Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Sangmoon Kim wrote: > > Hi, > I want to make a flash file system on a custom MPC755 board with a 64-bit (bus width) flash memory. > I set CONFIG_MTD_PHYSMAP_BUSWIDTH = 8 at kernel configure, and when it boots the following message appears. > > physmap flash device: 400000 at 7c000000 > genprobe_new_chip called with unsupported buswidth 8 > CFI: Found no Physically mapped flash device at location zero > > Is it possible to make a flash file system with a flash memory of 64 bit bus width? If possible, what's the method? Please let me know. You could fix it so it can handle buswith 8 or you could write a mapping driver that fakes buswidth 4. The simplest is to make the first 32 bits of the bus one region and the last 32bits another. So if you have 8MiB you get 4MiB only using the first 32 bits followed by 4MiB using the hi 32 bits. This way the autdetetcion should work ok. -- Kenneth Johansson Ericsson AB Tel: +46 8 404 71 83 Borgafjordsgatan 9 Fax: +46 8 404 72 72 164 80 Stockholm kenneth.johansson@etx.ericsson.se ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/