From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [209.87.241.202] (helo=[10.0.1.46]) by pentafluge.infradead.org with esmtpsa (Exim 4.43 #1 (Red Hat Linux)) id 1D9XDJ-0000AO-4v for linux-mtd@lists.infradead.org; Thu, 10 Mar 2005 23:37:11 +0000 Message-ID: <4230DA22.8070305@netwinder.org> Date: Thu, 10 Mar 2005 18:37:06 -0500 From: Ralph Siemsen MIME-Version: 1.0 To: linux-mtd@lists.infradead.org Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Subject: Autodetection problems List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , I'm using kernel 2.6.10 on a PPC440GX with TWO 32MiB Intel J-series Strataflash. These are x16 devices and they are arranged in parallel across the 32-bit data bus (interleave=2). They share a common chip select and are mapped at the top of the address space. With mostly default options to the kernel, the MTD autodetection logic performs two calls to do_cfi_probe() at offset 0x000000 and 0x2000000, and then proclaims, erroneously: Found 1 x32 devices at 0x0 in 32-bit bank Attempts to use the flash in this state fail miserably (tons of block bitmap errors, cannot access beyond 32MiB, etc). Thanks to suggestion by ThomasG, I switched on the advanced options, selected _only_ 32-bit buswidth, and _only_ interleave of 2. Now the kernel reports what I expected: Found 2 x16 devices at 0x0 in 32-bit bank and everything works like it a charm. Though I'd mention this in case anyone encounters similar situation. I'm not sure if the autodetection code is meant to work in my situation... PS. I also learned that having jffs2 debug level set at 2 causes considerably slowdown - doing an "ls" was taking 11 seconds. Putting debug back to 0 makes everything work quickly as you'd expect. I'm currently not subscribed to the list, please cc: any replies! -Ralph