mån 2014-05-19 klockan 10:22 +0200 skrev Hans de Goede: > To clarify from my POV I would like the suggested change to go upstream > eventually as it unifies the FEL non FEL version of the SPL. AFAIK upstream > would like us to see if we can move to a single build where we: > 1) Always include mmc support > 2) leave the necessary ram free for FEL mode > 3) build both non FEL and FEL SPL binaries in the final build phase, using > a different header but otherwise identical.
Imho it does not make sense to unify the two. They serve very different purposes and run in quite different setups. The FEL binary sole purpose is to prepare the CPU and DRAM controller allowing applications (i.e. u-boot) to be loaded to DRAM. It is NOT in itself a loader like SPL. FEL mode has much less available SRAM than the other boot modes, and also starts at another memory location, and finally return execution to the FEL boot rom after finishing the board setup. The SPL has almost whole SRAM available, and takes over the board completely. Why do you at all want to see MMC support etc in the FEL binary? I do not see a use case for MMC support in FEL. You accmplish that by loading u-boot. It is theoretically possible to add the FEL binary as another link target while building SPL, but we do have a slightly different u-boot environment in the main u-boot binary built for FEL use, to allow full system boot using FEL mode (u-boot + kernel + initrd all loaded to ram via fEL). Apart from this all FEL mode is is a linker script isolating the DRAM setup code as a small standalone function to be called by BROM/FEL boot ROM. Ah, right, there is also a small start.o stub object (0 bytes) in FEL mode to not take over the CPU, leaving stacks etc in place. Regards Henrik -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
