by having uboot_autoload() do the fdt setup (which may load a file) rather
than waiting until we're actually in the process of launching the kernel.
As part of making this happen...
- Define LOADER_FDT_SUPPORT on the uboot/lib compile command line when
MK_FDT is set.
- Make fdt_setup_fdtb() public.
- Declare public fdt_whatever() functions in a header instead of using
scattered extern decls in .c files.
- Add "fdt addr" subcommand that lets you specify preloaded blob address
- Do not pre-initialize blob for "fdt addr"
- Do not try to load dtb every time fdt subcommand is issued,
do it only once
- Change the way DTB is passed to kernel. With introduction of "fdt addr"
actual blob address can be not virtual but physical or reside in
area higher then 64Mb. ubldr should create copy of it in kernel area
and pass pointer to this newly allocated buffer which is guaranteed to work
in kernel after switching on MMU.
- Convert memreserv FDT info to "memreserv" property of root node
FDT uses /memreserve/ data to notify OS about reserved memory areas.
Technically it's not real property, it's just data blob, sequence
of <start, size> pairs where both start and size are 64-bit integers.
It doesn't fit nicely with OF API we use in kernel, so in order to unify
thing ubldr converts this data to "memreserve" property using the same
format for addresses and sizes as /memory node.
The code previously assumed that copyin/copyout did no
address translation and that the device tree blob could
be manipulated in-place (with only a few adjustments for
the ELF loader offset). This isn't possible on all platforms,
so the revised code uses copyout() to copy the device tree
blob into a heap-allocated buffer and then updates the
device tree with copyout(). This isn't ideal, since it
bloats the loader memory usage, but seems the only feasible
approach (short of rewriting all of the fdt manipulation
routines).
Enable using the statically embedded blob from the kernel, if present. The KLD
loaded DTB takes precedence, but they are both recognized and handled in the
same way.
Submitted by: Lukasz Wojcik
Obtained from: Semihalf
MFC after: 1 week
o This is disabled by default for now, and can be enabled using WITH_FDT at
build time.
o Tested with ARM and PowerPC.
Reviewed by: imp
Sponsored by: The FreeBSD Foundation