Cortex-a9 banked registers

Using cortex-a9 (zynq 7010)
With the gcc toolchain.

I'm working on porting our RTOS scheduler to this platform.

In a privileged exception state (SVC,IRQ,FIQ etc..) 

trying to restore a saved context.

ldm r0,{r0-r12,sp,lr,pc}^


Does not seem to be restoring the user/system mode sp and lr.
I thought that the ^ would force this to operate on the user/system registers, not the banked registers.

The following code DOES work,
I'm just trying to understand why the code above does not.

add r0,#52
ldm r0,{sp,lr}^ /* This works why doesn';'t it work in the previous statement */
nop
sub r0,#52  
ldr r1,[r0,#60]
mov lr,r1
ldm r0,{r0-r12} 
movs pc,lr







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