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<DIV>Hi,</DIV>
<DIV> </DIV>
<DIV>In the irq_save_user_regs in start.S, the "user mode" SP and LR</DIV>
<DIV>are saved on the stack using :</DIV>
<DIV> stmdb r8,{sp,lr}^</DIV>
<DIV> </DIV>
<DIV>This is a multiple register transfer instruction with the S bit set.</DIV>
<DIV>When this bit is set and the pc register is not listed among the register
to be saved,</DIV>
<DIV>this means the user mode register will be saved, instead of the current
mode register.</DIV>
<DIV> </DIV>
<DIV>However, I can't see any place in u-boot where we switch to user mode. What
is the signification of</DIV>
<DIV>this instruction ?</DIV>
<DIV> </DIV>
<DIV>Does it mean :</DIV>
<DIV> save sp_svc and lr_svc in the location pointed to by
r8,</DIV>
<DIV> </DIV>
<DIV>Or</DIV>
<DIV> save sp_user and lr_user in the location pointed to by
r8.</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>In the first case it could be useful, but in the latter it is useless since
we never switch to</DIV>
<DIV>user mode.</DIV>
<DIV> </DIV>
<DIV>Am I right ?</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>TIA for any informations.</DIV>
<DIV> </DIV>
<DIV>JP Francois</DIV></BODY></HTML>