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arch/xtensa: Use the software interrupt when saving context too.

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Signed-off-by: Abdelatif Guettouche <abdelatif.guettouche@espressif.com>
This commit is contained in:
Abdelatif Guettouche 2022-03-08 10:25:07 +01:00 • committed by Petro Karashchenko
parent 329db99e51
commit 71ba4a6b76
1 changed files with 5 additions and 108 deletions
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113
arch/xtensa/src/common/xtensa_context.S
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@ -276,96 +276,6 @@ xtensa_context_save:
#ifndef __XTENSA_CALL0_ABI__
/****************************************************************************
* Name: _xtensa_save_hook:
*
* Input State:
* True return value has already been saved
* a0 = The return value into xtensa_context_save()
* a2 = The address of the register state structure
*
* Return state:
* a0, a3 modified.
* Other values as on entry
* Returned value is in a3 (non-stanadard)
*
****************************************************************************/
.type _xtensa_save_hook, @function
.align 4
.literal_position
.align 4
_xtensa_save_hook:
/* Save the return value of 1 that will be used when returning from a
* context switch. NOTE that the returned value from this function is
* expected in a3 (not the usual a2). This also frees up a3 for a use
* as a scratch register.
*/
movi a3, 1 /* Set saved a3 to 1 */
s32i a3, a2, (4 * REG_A3)
/* Save the rest of the processor state.
*
* REVISIT: We could save a lot here. It should not be necessary to
* preserve all of these registers. The ABI permits volatile, callee-
* saved, registers to be clobbered on function calls. We save the
* whole tamale here mostly for debug purposes.
*
* NOTE that a3 was saved above. The true a0 return value was saved
* in xtensa_context_save. The a0 value saved below is the return into
* xtensa_context_save.
*/
rsr a3, PS /* Save callee's PS */
s32i a3, a2, (4 * REG_PS)
s32i a0, a2, (4 * REG_PC) /* Save Return address as PC */
s32i sp, a2, (4 * REG_A1) /* Save callee's SP */
s32i a2, a2, (4 * REG_A2)
s32i a4, a2, (4 * REG_A4) /* Save remaining registers */
s32i a5, a2, (4 * REG_A5)
s32i a6, a2, (4 * REG_A6)
s32i a7, a2, (4 * REG_A7)
s32i a8, a2, (4 * REG_A8)
s32i a9, a2, (4 * REG_A9)
s32i a10, a2, (4 * REG_A10)
s32i a11, a2, (4 * REG_A11)
/* Call0 ABI callee-saved regs a12-15 */
s32i a12, a2, (4 * REG_A12)
s32i a13, a2, (4 * REG_A13)
s32i a14, a2, (4 * REG_A14)
s32i a15, a2, (4 * REG_A15)
rsr a3, SAR
s32i a3, a2, (4 * REG_SAR)
#if XCHAL_HAVE_S32C1I != 0
rsr a3, SCOMPARE1
s32i a3, a2, (4 * REG_SCOMPARE1)
#endif
#if XCHAL_HAVE_LOOPS != 0
rsr a3, LBEG
s32i a3, a2, (4 * REG_LBEG)
rsr a3, LEND
s32i a3, a2, (4 * REG_LEND)
rsr a3, LCOUNT
s32i a3, a2, (4 * REG_LCOUNT)
#endif
/* NOTE that the returned value is through a3 */
movi a3, 0 /* Return zero, no context switch */
ret
.size _xtensa_save_hook, . - _xtensa_save_hook
/****************************************************************************
* Name: xtensa_context_save:
*
@ -396,25 +306,12 @@ _xtensa_save_hook:
xtensa_context_save:
ENTRY(16)
/* Save the true return address in the register save structure (a0). */
mov a3, a2
movi a2, SYS_save_context
movi a4, XCHAL_SWINT_CALL
wsr a4, intset
rsync
s32i a0, a2, (4 * REG_A0) /* Save true return address (a0) */
/* Then perform the actual state save in _xtensa_save_hook. The saved
* EPC will be set to the return from this function then we will do the
* RET(16) window fix-up.
*/
call0 _xtensa_save_hook /* Save full register state */
/* a0 and a2 will be automatically restored in the context switch case
* with a3=1. In the non-context switch return with a2=0, a2 will still
* be valid, but we have to restore a0 ourself. The following should
* work in either case.
*/
l32i a0, a2, (4 * REG_A0) /* Recover the true return address (a0) */
mov a2, a3 /* Move a3 to the correct register for return */
RET(16)
.size xtensa_context_save, . - xtensa_context_save