From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-in-08.arcor-online.net (mail-in-08.arcor-online.net [151.189.21.48]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.arcor.de", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id EBCCEDDEFE for ; Mon, 4 Jun 2007 03:36:48 +1000 (EST) In-Reply-To: <4662E7EA.70506@ru.mvista.com> References: <7fc919fce0761f861be3069a853d3169@bga.com> <1180769992.14025.1.camel@localhost.localdomain> <4662E7EA.70506@ru.mvista.com> Mime-Version: 1.0 (Apple Message framework v623) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: From: Segher Boessenkool Subject: Re: [PATCH] powerpc: Create "rom" (MTD) device prpmc2800 Date: Sun, 3 Jun 2007 19:36:38 +0200 To: Sergei Shtylyov Cc: ppcdev , Milton Miller List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , >> If it's a flash, compatible should be the chip type, and maybe as a >> second entry, what type of flash protocol (amd, intel, cfi, ...) it's >> compatible. > > As I've already (and repatedly) stated before, And you repeatedly got answers too, yet you choose to rehash this whole discussion again. > this gets you *nothing* WRT > selecting the proper driver in the current Linux MTD subsystem. Which Linux driver to use is not something that should be (directly) communicated in a device tree -- even if you take the position the device tree is a nice big configuration file for Linux, what if a new Linux flash subsystem shows up (or even simply a driver got renamed, etc.) -- the device tree on your board doesn't necessarily change when your kernel version does. > What it > actually *needs* to know is flash mapping information, It needs to know what kind of flash it is, and how it is connected -- i.e., it needs to describe the hardware. How Linux then decides to use it is its own game, but at least the device tree puts all the information it could possibly need out there. > the CFI/JEDEC interface > then can be deduced by probing Most of the time, sure. Not always. > -- so, this property ("ptobe-type"), although > specified in Documentation/powerpc/booting-without-of.txt, is optional. Who is talking about "probe-type"? We are talking about "compatible". Segher