From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 12 Feb 2008 10:54:09 +1100 From: David Gibson To: Timur Tabi Subject: Re: Could the DTS experts look at this? Message-ID: <20080211235409.GB18348@localhost.localdomain> References: <47ACE630.8090101@pikatech.com> <200802100647.56590.arnd@arndb.de> <47B08C76.3000009@freescale.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <47B08C76.3000009@freescale.com> Cc: linuxppc-dev@ozlabs.org, Arnd Bergmann List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, Feb 11, 2008 at 11:57:10AM -0600, Timur Tabi wrote: > Arnd Bergmann wrote: > > > Maybe we can introduce a more generic way of having conditional > > device nodes in the tree that get knocked out in the boot wrapper. > > I've been thinking about doing just this for quite some time now. I've had a > few informal discussions without people about. > > One idea is to allow attaching simple conditional expressions (like > X is <, =, or > than Y) to a node. It is the responsibility of the > code that parses the device tree to assign values to X and Y. For > instance, they could be the names of U-Boot environment variables. > If the expression is false, then the node is removed (or ignored) > from the device tree. If it's true, then it's kept in. In the binary tree representation itself? No way. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson