From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Wellington Date: Tue, 13 Apr 2004 09:05:40 -0600 Subject: [U-Boot-Users] Cascaded U-Boot setup question In-Reply-To: <20040413134641.63993.qmail@web60503.mail.yahoo.com> References: <20040413134641.63993.qmail@web60503.mail.yahoo.com> Message-ID: <407C01C4.7000509@lucent.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi- I have multiple Xilinx ML300 boards. Each one has its own ip address. Each board may have different boot parameters - baud rate, root file system, etc. Basically each board needs its own boot parameters stored in some kind of non-volatile storage. But there is no working non-volatile storage on these boards (yet), until I get I2C EEPROM working. Each board just boots from its copy of u-boot (which is generic) from the microdrive. Now, I could sit at each board and as it comes up, stop the autoboot and manually enter the parameters, but that's clunky. What I want to do is build a board-specific u-boot with parameters that are specific to that machine-name. So my boot process would be: 1) Load the generic u-boot off the microdrive. It knows what *machine-name* is and where to get the next stage at. 2) Use the generic u-boot to download a machine-specific u-boot, uboot-, which I can recompile and change at will since it resides on my tftp server. I don't have to rewrite the microdrive every time I want to change the boot parameters, all I have to do is build a new *second-stage* machine-specific u-boot- and put it in the /tftp download directory. 3) Run the 2nd u-boot (u-boot-) (which has the machine specific parameters) and let it boot the kernel with the arguments that I want. I tried downloading an uncompressed u-boot and loading it at 0x20000, then just saying "go 0x20000" and it doesn't work, it generates and illegal instruction exception. (is the starting address of u-boot not at the beginning of the .TEXT section - I'll go check after I send this email) I tried downloading a compressed u-boot with '-T standalone' and then saying "bootm 0x200000" and that doesn't work either. Is this doable? It should be. Does anybody know how to do it? I guess the other thing I "could" do is run expect on the serial port and set up the paramters that way, but I think the *cascaded u-boot* idea is better. -mike wellington wellington at lucent.com platforms at bithead.com