u-boot/board/netstal/hcu4
Sebastien Carlier 6d8962e814 Switch from archive libraries to partial linking
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>
2010-11-17 21:02:18 +01:00
..
config.mk Makefile: move all Power Architecture boards into boards.cfg 2010-10-18 22:12:04 +02:00
hcu4.c ppc4xx: Move ppc4xx headers to powerpc include directory 2010-09-23 09:02:05 +02:00
Makefile Switch from archive libraries to partial linking 2010-11-17 21:02:18 +01:00
README.txt Add PPC4xx-HCU4 and HCU5 boards: READMEs 2007-08-10 09:09:19 +02:00

HCU4 Configuration Details

Memory Bank 0 -- Flash chip
---------------------------

0xfff00000 - 0xffffffff

The flash chip is really only 512Kbytes, but the high address bit of
the 1Meg region is ignored, so the flash is replicated through the
region. Thus, this is consistent with a flash base address 0xfff80000.

The placement at the end is to be consistent with reset behavior,
where the processor itself initially uses this bus to load the branch
vector and start running.

On-Chip Memory
--------------

0xf4000000 - 0xf4000fff

The 405GPr includes a 4K on-chip memory that can be placed however
software chooses. I choose to place the memory at this address, to
keep it out of the cachable areas.


Internal Peripherals
--------------------

0xef600300 - 0xef6008ff

These are scattered various peripherals internal to the PPC405GPr
chip.

Chip-Select 2: Flash Memory
---------------------------

0x70000000

Chip-Select 3: CAN Interface
----------------------------
0x7800000


Chip-Select 4: IMC-bus standard
-------------------------------

Our IO-Bus (slow version)


Chip-Select 5: IMC-bus fast (inactive)
--------------------------------------

Our IO-Bus (fast, but not yet use)


Memory Bank 1 -- SDRAM
-------------------------------------

0x00000000 - 0x1ffffff   # Default 32 MB