From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Scholz Date: Thu, 25 Sep 2003 09:34:52 +0200 Subject: [U-Boot-Users] Startup for ARM boards? In-Reply-To: References: <3F715F47.1000904@imc-berlin.de> <3F716DF1.4070200@imc-berlin.de> <20030924105700.GM25427@pengutronix.de> <3F717ED3.5060900@imc-berlin.de> Message-ID: <3F729A9C.7080003@imc-berlin.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Marius, >>>>I will have a AT91RM9200 based board real soon now. But apparently the >>>>eval board AT91RM9200DK uses a different approach. They have a >>>>separate urloader to decompress and copy an U-Boot image into RAM and >>>>then jump there... > > Actually this "urloader" is called Thunderboot and is a ripped version > of ARMboot (a practice which seems to be quite fashionable these > days.) I never got round to asking them for the sources, nor do I > understand why they concealed it so pathetically :-) The flash images > even contain references to ARMboot. Maybe you want to have a go at > them? Ehm. Nope. That's not what I meant. They replace Thunderboot by their so called "AT91RM9200-Boot". Then they build a U-Boot version for the eval board AT91RM9200DK and gzip it. The AT91RM9200-Boot and the zipped version of AT91RM9200-U-Boot are stored in flash. Now all that AT91RM9200-Boot does when power-on is init the hardware (especially SDRAM), decompress u-boot.gz into SDRAM and jump to it. Atmel said: "We chose, to put a compressed boot due to memory mapping constraints. We need to keep a sector for environment variables the 8Kbyte-size sector is enough." IMHO this wasn't nessesary at all since they do seem to have flash with a few small sectors. But nevermind. They even provide a "AT91RM9200-Loader" which could be used to download the above files via the DEBUG UNIT (DBGU). I got these sources from Atmel. Now that I have these source I hope I can get this working on my board as well. Then when this two-(or three)-step version works I want to make U-Boot working like for all the other plattforms: init SDRAM, relocate and start. Ok? Steven