haiku/docs/develop/kernel/arch/arm/todo.txt

* Fix pre-ARMv7 support
  Currently the cross-tools are compiled to default to ARMv7, Cortex-A8, and
  hardware floating point. This works around the missing atomic support, see
  below. This should be done by setting the -mcpu,-march and -mfloat-abi
  switches at build time, however, they aren't passed on to haikuporter
  during the bootstrap build, leading to the ports failing to find the
  gcc atomic ops again.

* Determine how to handle atomic functions on ARM.
  GCC inlines are not supported, since the instructionset is ill-equiped for
  this on older (pre-ARMv7) architectures. We possibly have to do something
  similar to the linux kernel helper functions for this....
  On ARMv7 and later, this is not an issue. Not sure about ARMv6, we may get
  it going there. ARMv5 definitely needs us to write some code, but is it
  worth the trouble?

* Fix multilib support
  ARM-targetting versions of gcc are usually built with multilib support, to
  allow targetting architectures with or without FPU, and using either ARM
  or Thumb instructions. This bascally means a different libgcc and libstdc++
  are built for each combination.
  The cross-tools can be built with multilib support. However, we do some
  tricks to get a separate libgcc and libstdc++ for the kernel (without C++11
  threads support, as that would not build in the kernel). Building this lib
  is not done in a multilib-aware way, so you get one only for the default
  arch/cpu/abi the compiler is targetting. This is good enough, as long as that
  arch is the one we want to use for the kernel...
  Later on, the bootstrap build of the native gcc compiler will fail, because
  it tries to build its multilib library set by linking against the different
  versions of libroot (with and without fpu, etc). We only build one libroot,
  so this also fails.

* Figure out how to get page flags (modified/accessed) and implement it ;)
	use unmapped/read-only mappings to trigger soft faults
	   for tracking used/modified flags for ARMv5 and ARMv6

* Fix serial port mapping. Currently kernel uses the haiku_loader identity
  mapping for it, but this lives in user virtual address space...
  (Need to not use identity mapping in haiku_loader but just
  map_physical_memory() there too so it can be handed over without issues).

* Seperate ARM architecture/System-On-Chip IP code. Needed very early on 
  (Interrupt Controller, Timer IP block). Should use FDT for this too.

* Use FDT to remove all the seperate board definitions in the build. Use a 
  "minimal ARM architecture version" as the compile flag for ARM support. 
  This to be able to optimize a kernel build for a specific SoC (or family).

* KDL disasm module.
  cf.
  http://fxr.watson.org/fxr/source/arch/arm/arm/disassem.c?v=NETBSD

* Add KDL hangman to the boot floppy image for more enjoyment during porting....

* Userland...........

* Bootloader TODOs:
	- Better handling of memory ranges. Currently no checks are done, and
          memory is assumed to be a single contiguous range, and the "input"
          ranges for mmu_init are setup, but never considered.
        - Allocate the pagetable range using mmu_allocate() instead of identity
          mapping it. That way, there's a bit more flexibility in where to place
          it both physically and virtually. This will need a minor change on the
          kernel side too (in the early pagetable allocator).