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Xtensa port: Restore interrupted context the same way as premption resume.

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This was a kind of optimization that save few cycles in the cost of code
duplication. However the path where we resume from interrupt withouch changing
the running thread is buggy and leads to many tests to fail. For now I'd prefer
to remove this optimization and have a working port. Later, once everything is
OK, I'll have time to optimize things.

Change-Id: I7af58f383848d157b9f3b3fbeceede3e83f9ce61
Signed-off-by: Mazen NEIFER <mazen@nestwave.com>
This commit is contained in:
Mazen NEIFER 2017-02-03 21:10:45 +01:00 • committed by Andrew Boie
commit ef098bf410
1 changed files with 1 additions and 18 deletions
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19
arch/xtensa/core/xt_zephyr.S
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@ -165,18 +165,6 @@ _zxt_int_exit:
s32i a3, a2, KERNEL_OFFSET(nested) /* save nesting count */
bnez a3, .Lnesting /* !=0 after decr so still nested */
l32i a3, a2, KERNEL_OFFSET(current) /* a3 := _kernel->current */
beqz a3, .Lnoswitch
l32i a1, a3, THREAD_OFFSET(sp) /* SP - stack, a3 = current TCB */
l32i a4, a3, ___thread_arch_t_flags_OFFSET
movi a5, 0
and a4, a4, a5
beqz a4, .Lnoswitch
movi a4, 0
s32i a4, a3, 0 /* zero out the flag for next time */
1:
/*
* When using call0 ABI callee-saved registers a12-15 need to be saved
* before enabling preemption. They were already saved by _zxt_int_enter().
@ -199,11 +187,6 @@ _zxt_int_exit:
call0 _zxt_dispatch /* tail-call dispatcher */
/* Never returns here. */
.Lnoswitch:
/*
If we came here then about to resume the interrupted task.
*/
.Lnesting:
/*
* We come here only if there was no context switch, that is if this
@ -219,7 +202,7 @@ _zxt_int_exit:
* from which this was called. Interruptee's A0, A1, PS, PC are restored
* and the interrupt stack frame is deallocated in the exit dispatcher.
*/
l32i a0, a1, XT_STK_exit
l32i a0, sp, XT_STK_exit
ret
/*