From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Feretich Date: Fri, 25 Feb 2011 13:44:44 -0800 Subject: [U-Boot] OMAP3 Beagle Pin Mux initialization issue In-Reply-To: <20110222072813.F0E6214F034@gemini.denx.de> References: <4D6316A8.4090900@prodigy.net> <20110222072813.F0E6214F034@gemini.denx.de> Message-ID: <4D6822CC.406@prodigy.net> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Comments inline... On 2/21/2011 11:28 PM, Wolfgang Denk wrote: > Dear Bob Feretich, > > In message<4D6316A8.4090900@prodigy.net> you wrote: >> ... snipped... > You are right. Can you please submit a patch? For instructions > please see http://www.denx.de/wiki/U-Boot/Patches The patch was submitted. >> Also, I have observed the discussion regarding moving Pin Mux control to >> the kernel. This is fine except for pins that need to be configured ASAP >> after power-on. (The system could sit at the u-boot command prompt >> indefinitely, so the kernel pin mux configuration can be significantly >> delayed.). Please leave the hook so that u-boot customizers can >> configure their critical pins muxes. > Which pins would that be, for example? For the BeagleBoard, the pins of interest are the ones routed to the Expansion, J4, and J5 connectors. I am working with a local university. Students are building projects that interface to these connectors. Usually, the Linux boot delay is not a concern, but depending on the project, sometimes the pins need to be initialized before a "set time interval after power-on" expires (We can set the power-on reset delay to several hundreds milliseconds, but the time must be bounded.) By having the spot (beagle.c & beagle.h) in u-boot, where we can add our I/O Pin Mux initialization code, we can satisfy the needs of a bounded I/O initialization time. Regards, Bob Feretich > Best regards, > > Wolfgang Denk >