From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.sonologic.nl ([82.94.245.21]) by canuck.infradead.org with esmtp (Exim 4.43 #1 (Red Hat Linux)) id 1DmpCO-0001Ex-68 for linux-mtd@lists.infradead.org; Mon, 27 Jun 2005 04:42:37 -0400 Received: from [127.0.0.1] (mx1.sonologic.nl [82.94.245.21]) (authenticated bits=0) by mx1.sonologic.nl (8.13.3/8.13.3) with ESMTP id j5R8gVcM091756 for ; Mon, 27 Jun 2005 08:42:32 GMT Message-ID: <42BFBBFA.5040005@sonologic.nl> Date: Mon, 27 Jun 2005 10:42:34 +0200 From: Koen Martens MIME-Version: 1.0 To: linux-mtd@lists.infradead.org References: <42BC1FCB.8050003@sonologic.nl> In-Reply-To: <42BC1FCB.8050003@sonologic.nl> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: JEDEC / CFI questions & remarks List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Koen Martens wrote: > Second point: the EON clones of the original AMD chipsets have small > incompatibility in the method for reading out the manufacturer id. First > of all, a small fragment of jedec_probe.c: > > static inline u32 jedec_read_mfr(struct map_info *map, __u32 base, > struct cfi_private *cfi) > { > map_word result; > unsigned long mask; > u32 ofs = cfi_build_cmd_addr(0, cfi_interleave(cfi), > cfi->device_type); > mask = (1 << (cfi->device_type * 8)) -1; > result = map_read(map, base + ofs); > return result.x[0] & mask; > } > > > Basically, it reads some info from offset 0 relative to the start of the > flash memory. This is fine for AMD chips, which specify x00 as the (hex) > address to read out the manufacturer ID. The EON chips we use, however, > specify 100 (hex) as the offset of the manufacturer id. So what we did > here is change that first argument to cfi_build_cmd_addr from 0 to 0x100 > , which should thus work on both AMD and EON chips. But who knows what > this breaks on other chip types.... So, I wonder if this should be > submitted as a patch (along with the EON chip definitions), Actually, wouldn't it be better to put this address in the struct that defines the chip, just as the unlock addresses are..?? koen -- K.F.J. Martens, Sonologic, http://www.sonologic.nl/ Networking, hosting, embedded systems, unix, artificial intelligence. Public PGP key: http://www.metro.cx/pubkey-gmc.asc Wondering about the funny attachment your mail program can't read? Visit http://www.openpgp.org/