problem with initializing ppc-eabi r13 (sdata)

["Matthew dot R dot Wette at jpl dot nasa dot gov" <mwette at grover dot jpl dot nasa dot gov>]

I am looking for insight/help in working with the GNU loader.  I am 
trying to work with my own versions of startup code, etc to understand
how _start, _eabi, main, crt0, ... all work together.  I am using
gcc-2.95.3, binutils-2.12.1, gdb-5.2, all compiled on suse-linux 7.2
for target powerpc-eabi.  I am running against the (psim) simulator
in gdb via "run -e bug".

Here is the problem.  I want to initialize r13 with the address of the
start of .sdata segment.  If I look in the map file that is generated
by the loader, this address, given by _SDA_BASE_, is 0xa5a8.  When I
copy _SDA_BASE_ to "v1" and print it out from the program I get 0x125a8.
Bitwise these are

	0xa5a8		0000 0000 0000 0000 1010 0101 1010 0100
	0x125a8		0000 0000 0000 0001 0010 0101 1010 0100
                                          ^ ^
Does anyone have a clue what is going on here and what I might be going
wrong?   Any help would be appreciated.  Relevant snippets of code 
included below.

Thanks,
Matt


--- run ---

	albacore$ powerpc-eabi-run -e bug load4
	v1=0x125a8 (_SDA_BASE_)


--- load4.map ---

.sdata          0x0000a5a8      0x120
                0x0000a5a8                PROVIDE (__sda_base, .)
                0x0000a5a8                __sdata_start = .
 

--- main.c ---

	unsigned long v1;

	printf("v1=0x%x (_SDA_BASE_)\n", v1);


--- Makefile ---
load4: main.o kos.o kos1.o kos0.o kos_i.o kos_n.o kos4b.ld
        powerpc-eabi-ld -o load4 \
                -M >load4.map \
                -g -N -Bstatic -T kos4b.ld \
                -L/usr/local/powerpc-eabi/lib \
                kos_i.o \
                main.o kos.o kos1.o kos0.o \
                -lucos1 --start-group -lmvme -lc --end-group \
                kos_n.o


--- kos_i.S ---

	.section ".sdata","aw"
	.weak	_SDA_BASE_
	.type	_SDA_BASE_,@object
_SDA_BASE_:


--- kos1.S (startup code) ---

	.section ".got"
	.align 2
.LCTOC1 = .
.Ltable = .-.LCTOC1
.Lsda   = .-.LCTOC1
	.long	_SDA_BASE_

_start:
	...
	.extern v1
	lwz	%r7,.Lsda(%r5)
	lis	%r6,v1@ha
	stw	%r7,v1@l(%r6)


--- kos4b.ld ---

PHDRS
{
  headers PT_PHDR FILEHDR PHDRS ;
  text PT_LOAD ;			/* text */
  data PT_LOAD ;			/* data */
}

SECTIONS
{
  .text :
  {
    . = 0x0000;
    kos0.o(.text)
    . = 0x3000;
    kos1.o(.text)
    kos.o(.text)
    *(.text)
  } :text =0
  PROVIDE (__etext = .); PROVIDE (_etext = .); PROVIDE (etext = .);
  .sdata : {
    PROVIDE(__sda_base = . );
    __sdata_start = . ;
    *(.sdata)
    __sdata_end = . ;
    kos*(.sbss)
    *(.sbss)
  } :data = 0
  ...



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