From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailrelay005.isp.belgacom.be (mailrelay005.isp.belgacom.be [195.238.6.171]) by ozlabs.org (Postfix) with ESMTP id 43653DE2C0 for ; Wed, 26 Mar 2008 04:23:35 +1100 (EST) From: Laurent Pinchart To: Sergei Shtylyov Subject: Re: OF compatible MTD platform RAM driver ? Date: Tue, 25 Mar 2008 18:23:26 +0100 References: <200803101606.39184.laurentp@cse-semaphore.com> <200803251744.46001.laurentp@cse-semaphore.com> <47E93010.5090904@ru.mvista.com> In-Reply-To: <47E93010.5090904@ru.mvista.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1966428.EamxGzEXNU"; protocol="application/pgp-signature"; micalg=pgp-sha1 Message-Id: <200803251823.32039.laurentp@cse-semaphore.com> Cc: ben@simtec.co.uk, linuxppc-dev@ozlabs.org, linux-mtd@lists.infradead.org, David Gibson List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --nextPart1966428.EamxGzEXNU Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On Tuesday 25 March 2008 18:02, Sergei Shtylyov wrote: > Laurent Pinchart wrote: >=20 > > > Heh, there was a whole company against mentioning "mtd" when we start= ed=20 > > > working on this (of course, the first idea was to call the flash devi= ce > > > type "mtd"). I don't think "mtd" looks good here -- I'd suggest > > > "flash-ram" (if this is just a linearly mapped NVRAM). >=20 > > I'm fine with "flash-ram" (even thought it looks a bit weird). I'll > > prepare a patch. >=20 > Yeah. I forgeot that "flash" means EEPROM. Actually, the main facts about= =20 > the NVRAM that I'd want to be stated in the "compatible" property is that > it's non-volatile and directly/lineraly mapped... Just "nvram" doesn't s= eem=20 > enopugh, maybe "linear-nvram" is. Direct mapping is a hard requirement for the nvram if we want to use it wit= h=20 the MTD subsystem. Regarding non-volatility nothing prevents a user from=20 using a volatile RAM as an MTD device, but there's little point in doing so= =2E=20 Would it be acceptable for the "linear-nvram" specification not to include= =20 volatile RAM ? ROM chips would be excluded too. Is that an issue ? > And we can specify "device_type" of "nvram" indeed (and #size).=20 I suppose you meant #bytes. What about sub-partitions support ? Nothing prevents RAM-based MTD devices= =20 from being partioned. Would it be acceptable to reference the CFI/JEDEC fla= sh=20 section in Documentation/powerpc/booting-without-of.txt in the description = of=20 the nvram node ? Best regards, =2D-=20 Laurent Pinchart CSE Semaphore Belgium Chauss=E9e de Bruxelles, 732A B-1410 Waterloo Belgium T +32 (2) 387 42 59 =46 +32 (2) 387 42 75 --nextPart1966428.EamxGzEXNU Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQBH6TUU8y9gWxC9vpcRAnKcAKC3rEmYzaH8/rq6Ye10bwpRtw8IrACfVZVE 1o0asnKZlpZJ+h2OmFZTkvo= =ngU1 -----END PGP SIGNATURE----- --nextPart1966428.EamxGzEXNU--