On Thu, Apr 11, 2013 at 12:39:00PM -0600, Chris Friesen wrote: > On 04/11/2013 12:12 PM, Kumar Gala wrote: > > > > On Apr 11, 2013, at 10:44 AM, Chris Friesen wrote: > > > >> > >> Hi all, > >> > >> We've got a powerpc system that uses u-boot. In our environment on > >> bootup u-boot does a DHCP to get networking info, then uses TFTP to > >> get the kernel, which then does DHCP again and NFS-mounts the > >> initial root filesystem. > >> > >> What's the standard practice for this sort of thing when using > >> device tree blobs? Do most people use multi-file images or do they > >> TFTP scripts to load and execute separate kernel/dtb files? > > > > We've normally just done multiple tftp fetches and one grabs dtb and > > one grabs kernel. > > Do you hardcode the path to the file in the firmware? Or do you upload > a script that knows the path to the file? > > In our case the path to the boot file(s) depends on which slot the card > being booted has been inserted in. The DHCP server knows what the path > is, so it can set dhcpd.conf appropriately, but we need to get that > information to the firmware on the card being booted. >
Hello Chris, I use a hardware setup which sounds similar to yours. The DHCP server controls which file is sent to each card. I use the FIT image format to combine a kernel, dtb, and initrd in one package. Then the U-Boot command "dhcp $address" sets up the network and tftp's the filename sent by the DHCP server. You don't need to invoke the U-Boot command "tftp" if you only have one image. "dhcp" is enough. I used the U-Boot doc/uImage.FIT/*.its examples to get started, and wrote my own custom .its file for my board. I don't use anything other than the vmlinux.bin.gz provided by the kernel build. Hope it helps, Ira _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev