From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerry Van Baren Date: Thu, 22 Mar 2007 19:38:17 -0400 Subject: [U-Boot-Users] Where in u-boot is the RAM "Mode Register" programmed? In-Reply-To: <004b01c76ccc$e1bac370$6accdf0a@TQICORP.local> References: <004b01c76ccc$e1bac370$6accdf0a@TQICORP.local> Message-ID: <46031369.7000702@comcast.net> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Bjook wrote: > [snip] > The only problem is my hardware layout guy decided to mangle the address > lines when he connected the RAM to the ARM processor. His reasoning was > that a RAM address is a RAM address is a RAM address. If you always > access the RAM from the Arm chip then the mangled lines will always get > decoded and you will get the correct data value. > > What the layout guy did not realize was that this RAM has a Mode > Register that needs to be programmed. Where does this happen in > u-boot? If I can find out where it is set then I can decode the mangled > address lines and put the proper value in. > > Also I will set the ?burst read? to 0. > > Do you think this situation salvageable? A10 is the same because it is > a special line but I may need to jumper A8 and A9 since it looks like > they are only used to program the address register. [snip] > Next time I will fix the mangled lines but I really need to prove out my > design on my current 50 boards since another spin takes around a month > (because of BGA chips). > > -Bjook Oooooo, you get this working he owes you a lifetime supply of beer. Make him pay for a long time, don't drink it all at once. ;-) grep is your friend and start.S is the place to start. /u-boot/cpu/arm920t/at91rm9200/lowlevel_init.S I'm not familiar with the ARM(r) memory controller. If it just does address and data (looks like it), it should be salvageable (if so, it probably isn't worth re-laying out the board unless you have other problems). The initialization is a stream of defines of (address / data) pairs at the labels SMRDATA and SMRDATA1. You will have to warp the addresses, but it probably will work. Good luck, gvb