[U-Boot-Users] U-Boot-V2 tree available

[Sascha Hauer]

Hi all,

The U-Boot-v2 tree is now available. You can get it from the usual
custodian page:

git clone git://www.denx.de/git/u-boot-v2.git u-boot-v2-arm

I already began to integrate the changes proposed in our last
discussion, but unfortunately the start.S file for mpc5200 got quite
broken during this (at least if you want to compile a relocatable
binary). I think it should be our first target to work here
since it prevents us from inserting other powerpc targets. If you think
this is too broken to be usable at all, we may have to start off from
the latest vanilla version. Another thing missing are Grants
consolidate-lds-patches (there is currently only one linker script, but
it should be in the ppc part, not in the board part).

It is too early to integrate extensive board support. On the other
hand this is a bootloader which needs board support and the sandbox
target is not enough for lowlevel things, so I think everyone interested
in working with this tree should pick his favourite board (or maybe the
weirdest, to see what constraints we have) and integrate the support
into the tree.

If you find things that are too unflexible or things that
work-for-noone-except-Sascha please complain ;)

latest changes include:

- 'linux' target has been renamed to 'sandbox' as proposed from Carsten
  Schlote.

- The console support is now position independent, so it can be used in
  early init stages where the runtime address does not match the link
  address. This is useful to start the same binary image from different
  locations (SDRAM/upper flash/lower flash). See include/reloc.h on how
  it works.

- In early init stages there are normally no writable global variables,
  because they are in flash. Traditionally this has been solved with the
  global_data struct, which was in SRAM during early init. This has been
  replaced with a special linker section. The contents of this section
  are copied to SRAM during startup and copied to SDRAM after startup.
  The contents can be accessed with the INITDATA() macro. See
  include/reloc.h on how it works.

- The early console is adjustable in both baudrate and port during early
  init. At the moment there is no mechanism though to read the
  environment in this stage to make use of this feature.

- There is a kconfig option to compile a relocatable U-Boot binary
  (CONFIG_RELOCATABLE). This option is currently broken, mostly because
  reloc_offset() uses the hardcoded TEXT_BASE to calculate the
  difference between link- and runtime address. Also the stack is placed
  at the end of available RAM and u-boot below it. This is a bad idea
  and was only to get something running. Maybe someone with assembler
  knowledge could have a look into it?

Regards
  Sascha

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