With recent toolchain versions, some boards would not build because
or errors like this one (here for ocotea board when building with
ELDK 4.2 beta):
ppc_4xx-ld: section .bootpg [fffff000 -> fffff23b] overlaps section .bss [fffee900 -> fffff8ab]
For many boards, the .bss section is big enough that it wraps around
at the end of the address space (0xFFFFFFFF), so the problem will not
be visible unless you use a 64 bit tool chain for development. On
some boards however, changes to the code size (due to different
optimizations) we bail out with section overlaps like above.
The fix is to add the NOLOAD attribute to the .bss and .sbss
sections, telling the linker that .bss does not consume any space in
the image.
Signed-off-by: Wolfgang Denk <wd@denx.de>
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.
ARM memory layout fixes: the abort-stack is now set up in the
correct RAM area, and the BSS is zeroed out as it should be.
Furthermore, the magic variables 'armboot_end' and 'armboot_end_data'
of the linker scripts are replaced by '__bss_start' and '_end',
resp., which is a further step to eliminate unnecessary differences
between the implementation of the CPU architectures.
Move most of the timer interrupt related PPC code to ppc_lib/interrupts.c
* Patch by Anders Larsen, 17 Sep 2003:
Bring ARM memory layout in sync with the documentation:
stack and malloc-heap are now located _below_ the U-Boot code
- fix spelling errors
- set GD_FLG_DEVINIT flag only after device function pointers
are valid
- Allow CFG_ALT_MEMTEST on systems where address zero isn't
writeable
- enable 3.rd UART (ST-UART) on PXA(XScale) CPUs
- trigger watchdog while waiting in serial driver
- remove trailing white space, trailing empty lines, C++ comments, etc.
- split cmd_boot.c (separate cmd_bdinfo.c and cmd_load.c)
* Patches by Kenneth Johansson, 25 Jun 2003:
- major rework of command structure
(work done mostly by Michal Cendrowski and Joakim Kristiansen)
instead CFG_MONITOR_LEN is now only used to determine _at_compile_
_time_ (!) if the environment is embedded within the U-Boot image,
or in a separate flash sector.
* Cleanup CFG_DER #defines in config files (wd maintained only)
