From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Maenner Date: Tue, 18 Feb 2003 18:15:22 -0800 Subject: [U-Boot-Users] uboot newbie - tqm823 and memory conf question References: <20030217222028.6E5B5C6E0D@atlas.denx.de> Message-ID: <3E52E8BA.4000402@aehr.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de OK, thanks again! Wolfgang Denk wrote: > In message you wrote: > >>Thanks! > > > You're welcome. > > >>>So depending if you have CAN on your modules or not you can chose >>>form CS4...CS7 or from CS3...CS7. >>> >> >>Well then, how does the CPU "know" about that area? > > > Ummm... please read the memory controller section of the MPC8xx > User's Manual. Found it! Chapter 15. Digesting it... ---snip--- > >>- How does the CPU know, that it is SRAM or something else? > > > It doesn't know, and it doesn't need to know. It just goes through > the memory controller registers to find a BRx/ORx pair that matches > the physical address, and then it accesses the corresponding CS > according to the other params in BRx/ORx. > > Not that the scanning always starts at BR0/OR0, so if you define > overlapping memory regions always the first one will win. > Good info. ---snip--- > >>I will search in the source there. > > > What for? Just add it to your Linux device driver's init() code. > If the "when" almost doesn't matter, it could be done there. ---snip--- Thanks a lot Wolfgang for your help! Have a successful show in Nuremberg! -- Thomas Maenner