On Thu, Mar 20, 2008 at 4:21 PM, Andy Green <[EMAIL PROTECTED]> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Really, why would we need any device driver in the bootloader? > > Bootloader are not meant to deal with the device, they let the OS do it. > > We have to have a little device-specific knowledge in there to get at > the kernel image over SD on VFAT for example, or it seems NAND bad block > skipping, but it should be really really minimal. >
At least the way I use drivers in bootloaders and in u-boot in particular is to validate the hardware without a kernel. Once a version u-boot is loaded, hacking various kernel versions is that much easier. u-boot has a shell that can get deep into protocals like I2C, SPD, CFI and many others. Memory is arguably the most tricky part in bringing up an OS and something that the kernel expects to be ready to go, and u-boot 's community and code is a good asset here. > > > And you're right, we could write a dozen of minimal bootloaders by the > > same time we spend fixing/maintaining u-boot. > > Well if U-Boot already came patched and working, to start with it would > be quicker to use it. But I prefer to get rid of it. By getting rid of u-boot you'd IMHO be losing one of the attractions to openmoko: a low barrier to-entry hackable device. In my case I'm a contributor to u-boot, knows how it works a bit, and am looking forward to hacking it on openmoko. Writing your own bootloader or using kexec may be interesting to some, and since its open source no one is stopping you. But at least one other option is taking advantage of an active and knowledgable community like uboot As far as patches and u-boot are concerned, I talked to some people at the recent bossa conference here in brazil and expect to see some progress soon. I myself am waiting for the freerunner to get released, as I don't have any hardware yet. Cheers, Robert
