2012/2/8 Paul Brook <p...@codesourcery.com> > > > I suspect we want to replace the arm_load_kernel call with an > > > arm_linux_loader device with appropriate properties. > > > > Ok, so does this mean the machine model would still explicitly > instantiate > > the bootloader device? > > Yes. Bootloaders inherently have machine specific knowledge. They need to > know ram location, board ID, secondary CPU boot protocols, etc. Requiring > the > user specify all these things separately from the rest of the machine > description is IMO not acceptable. > > So what im suggesting here is that machines export these properties to a globally accessible location. Perhaps via the machine opts mechanism? Then we are in a best of both worls situation where machine models do not need bootloader awareness yet bootloaders can still query qemu for ram_size, smp#, board_id and friends.
> > Will there be a way of removing the bootloader from > > the machine model so if I need to create my own custom bootloader flow i > > can? We are doing some custom non-linux boots in our application where > > arm-boot.c is not working for us so being able to swap out arm_boot.c for > > another implemenation is one of our goals. The bootloader-as-a-device > flow > > is ideal for this but only works if a user can choose their bootloader on > > the command line. > > I think that's solved the same lines as any other custom machine variant. > It's also part of the reason I think it's important to cleanly separate > devices that provide functionality from those that are just convenience > objects for creating a particular assembly of devices. > > Having generic ELF and maybe binary blob image loaders is certainly useful. > They can all coexist happily within the same machine. > > I'm inclined to say that anything else isn't worth the effort. Users with > other special needs can use third party tools[1] to embed/wrap their magic > in > a regular image. > > Paul > > [1] In many cases cases you just need to splat the supplied > bootloader+kernel > images into ram, not postprocessing is necessary. For most of the rest > objcopy is sufficient. >
