Dear Rob Sciuk, > On Mon, 4 Mar 2013, Marek Vasut wrote: > > Date: Mon, 4 Mar 2013 13:15:33 +0100 > > From: Marek Vasut <marek.va...@gmail.com> > > To: r...@controlq.com > > Cc: arm@openbsd.org > > Subject: Re: Any platform useful as a graphical desktop? > > > > Dear Rob Sciuk, > > > >> On Sun, 3 Mar 2013, Marek Vasut wrote: > >>> Bootp is weird junk, just use tftp to transfer your files (using the > >>> 'tftp' command in U-Boot) and then 'bootm' that stuff. Note that the > >>> FDT location is passed to the kernel in one of the CPU registers, R2 > >>> IIRC. > >>> > >>> Best regards, > >>> Marek Vasut > >> > >> True, but dhcpd/bootp only knows about the kernel file ... when using > >> the dhcp protocol to download the file system, fdt and kernel, you have > >> to explicitly arrange for the files other than the kernel image to be > >> loaded into memory first. Hence the extension ... and yes, R2 contains > >> a pointer to the fdt (on PPC, not sure about ARM), but it has to get to > >> RAM somehow ... unless you have it in flash and are point to it > >> directly ... > > > > Uh, so why not switch to tftp or nfs since it's much easier to work with > > ? > > This was a work related project on a PPC/FPGA(7) ATCA platform. A number > of constraints were in place, and the mechanism described allows MAC > address setup in U-Boot (as determined by querying the Shelf controller > via a serial port), and a great deal of flexibility in that by changing > ONLY the dhcpd configuration, we can load different OS/FPGA loads onto the > blade. It has worked very well for us, as the ATCA platform is a > controlled environment (and WE have control). I don't defend the design > decision, only mention it as it works well. Also, this application is a > high powered telecom simulator aimed at CO's of major telecom carriers, > not a mass market product such as PDA. > > Your comments regarding the aged Bootp protocol were well taken, but a > close code inspection gave us the all the necessary info to extend the > protocol, and the end result has provided good flexibility for future > enhancements with a minimum of coding. > > Given another project, particularly one aimed at end users, I would be > loathe to use Bootp (extended) given the ability to use tftp and/or NFS > directly, and I would love to see the OF support become a widespread > standard mechanism within the ARM world ... so basically, yes, I agree > with you 8-).
True, the OF is getting a lot of traction. Btw. setting up the mac address in u- boot is possible too by setting 'ethaddr' variable in the command line. It's even propagated into the DT node as local-mac-address iirc. I recall the FECes do not have mac address written in them indeed. > Cheers, > Rob. > > ps: Any thoughts about supporting a (net?) BSD on the Palm platforms?? > You did some very nice work in this area prior to your graduation!!!!! I had some ... uh ... disagreement with Theo. Besides, I now work on Linux/U- Boot a lot, so that's about it. Best regards, Marek Vasut
