Before this commit, weak symbols were not overridden by non-weak symbols
found in archive libraries when linking with recent versions of
binutils.  As stated in the System V ABI, "the link editor does not
extract archive members to resolve undefined weak symbols".

This commit changes all Makefiles to use partial linking (ld -r) instead
of creating library archives, which forces all symbols to participate in
linking, allowing non-weak symbols to override weak symbols as intended.
This approach is also used by Linux, from which the gmake function
cmd_link_o_target (defined in config.mk and used in all Makefiles) is
inspired.

The name of each former library archive is preserved except for
extensions which change from ".a" to ".o".  This commit updates
references accordingly where needed, in particular in some linker
scripts.

This commit reveals board configurations that exclude some features but
include source files that depend these disabled features in the build,
resulting in undefined symbols.  Known such cases include:
- disabling CMD_NET but not CMD_NFS;
- enabling CONFIG_OF_LIBFDT but not CONFIG_QE.

Signed-off-by: Sebastien Carlier <sebastien.carlier@gmail.com>

Most people don't use the 'rarpboot' command, so only enable it when
CONFIG_CMD_RARP is defined.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

 Minor ./net cleanups - no functional changes
  - change #ifdef DEBUG printf(); #endif to just debug()
  - changed __FUNCTION__ to __func__
  - got rid of extra whitespace between function and opening brace
  - removed unnecessary braces on if statements

 gcc dead code elimination should make this functionally/size equivalent
 when DEBUG is not defined. (confirmed on Blackfin, with gcc 4.3.3).

Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>

Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

On 04 Oct 2008 Pieter posted a dns implementation for U-Boot.

http://www.mail-archive.com/u-boot-users@lists.sourceforge.net/msg10216.html


>
> DNS can be enabled by setting CFG_CMD_DNS. After performing a query,
> the serverip environment var is updated.
>
> Probably there are some cosmetic issues with the patch. Unfortunatly I
> do not have the time to correct these. So if anybody else likes DNS
> support in U-Boot and has the time, feel free to patch it in the main tree.

Here it is again - slightly modified & smaller:
  - update to 2009-06 (Pieter's patch was for U-Boot 1.2.0)
  - README.dns is added
  - syntax is changed (now takes a third option, the env var to store
    the result in)
  - add a random port() function in net.c
  - sort Makefile in ./net/Makefile
  - dns just returns unless a env var is given
  - run through checkpatch, and clean up style issues
  - remove packet from stack
  - cleaned up some comments
  - failure returns much faster (if server responds, don't wait for
    timeout)
  - use built in functions (memcpy) rather than byte copy.

Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Pieter Voorthuijsen <pieter.voorthuijsen@prodrive.nl>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

This change is in preparation for condtitionial compile support in the
build system.  By spliting them all into seperate lines now, subsequent
patches that change 'COBJS-y += ' into 'COBJS-$(CONFIG_<blah>) += ' will
be less invasive and easier to review

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

Based on patch by Mike Frysinger, 20 Jun 2006

Modifications are based on the linux kernel approach and
support two use cases:

  1) Add O= to the make command line
  'make O=/tmp/build all'

  2) Set environement variable BUILD_DIR to point to the desired location
  'export BUILD_DIR=/tmp/build'
  'make'

The second approach can also be used with a MAKEALL script
'export BUILD_DIR=/tmp/build'
'./MAKEALL'

Command line 'O=' setting overrides BUILD_DIR environent variable.

When none of the above methods is used the local build is performed and
the object files are placed in the source directory.

  add SNTP support and expand time server and time offset fields of
  DHCP support. See doc/README.SNTP

* Patch by Steven Scholz, 13 Dec 2004:
  Fix bug in at91rm920 ethernet driver

  Add support for NFS for file download

* Minor code cleanup

* Add support for TQM862L at 100/50 MHz

* Patch by Pantelis Antoniou, 02 Jun 2003:
  major reconstruction of networking code;
  add "ping" support (outgoing only!)