The code that's portable across different architectures begins at main(). I'll work on documenting what it expects.
eros/src/sys/arch/arm/kernel/lostart.S is the code that begins with the state left by the boot loader and ends by calling main(). It has a little code that is portable across ARM systems; most of the code is specific to the board or SOC. The portable code should be separated out. I've found that the best way to do that is to first write a new lostart.S for the new system and get it working, and then see what code there is in common between the two versions. Unless you want to write a new boot loader, you have an existing loader you will be working with. You need to write a new lostart.S that starts where your boot loader leaves off, and ends with the state main() expects. The current lostart.S can be a guide, but since you may not be familiar with the Cirrus EDB9315 system, I expect you'll have many questions. I would be very happy to help. I'm delighted that you want to port CapROS to this readily available system. I found that boot loaders aren't always well documented and I had to discover the specs by trial and error. For example, I had a system that was running, but my performance numbers were terrible. I came to realize that the boot loader hadn't set the clock speed, so my 200 MHz processor was actually running at the much slower default speed. Good luck. On 10/3/10 7:09 AM, vibi sreenivasan wrote: > I am trying to port capros to omapl138 based hawk board. > > On Sat, Oct 2, 2010 at 8:20 PM, Charles Landau<[email protected]> wrote: >> > On 10/2/10 1:07 AM, vibi sreenivasan wrote: >>> >> Is there any specification on what bootloader has to do before loading >>> >> os. >>> >> I think that is needed. Presently every thing in >>> >> eros/src/sys/arch/arm/kernel/Iostart.s is tailored for >>> >> booting from redboot. >>> >> >>> >> If we make a specification we can move some part to a regular >>> >> bootloader or minimal >>> >> initial program loader& make os specific part more portable& >>> >> general. ------------------------------------------------------------------------------ Virtualization is moving to the mainstream and overtaking non-virtualized environment for deploying applications. Does it make network security easier or more difficult to achieve? Read this whitepaper to separate the two and get a better understanding. http://p.sf.net/sfu/hp-phase2-d2d _______________________________________________ CapROS-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/capros-devel
