powerpc/8xx: No need to save r10 and r3 when not calling FixupDAR

r10 and r3 are only used inside FixupDAR function. So lets save them inside
that function only.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
This commit is contained in:
LEROY Christophe 2014-08-29 11:14:38 +02:00 committed by Scott Wood
parent 140a6a60ba
commit 5bcbe24f6c

View File

@ -485,20 +485,12 @@ InstructionTLBError:
*/
. = 0x1400
DataTLBError:
#ifdef CONFIG_8xx_CPU6
stw r3, 8(r0)
#endif
EXCEPTION_PROLOG_0
mtspr SPRN_SPRG_SCRATCH2, r10
mfspr r10, SPRN_DAR
cmpwi cr0, r10, 0x00f0
mfspr r11, SPRN_DAR
cmpwi cr0, r11, 0x00f0
beq- FixupDAR /* must be a buggy dcbX, icbi insn. */
DARFixed:/* Return from dcbx instruction bug workaround */
#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0)
#endif
mfspr r10,SPRN_SPRG_SCRATCH2
EXCEPTION_EPILOG_0
b DataAccess
@ -528,6 +520,10 @@ DARFixed:/* Return from dcbx instruction bug workaround */
/* define if you don't want to use self modifying code */
#define NO_SELF_MODIFYING_CODE
FixupDAR:/* Entry point for dcbx workaround. */
#ifdef CONFIG_8xx_CPU6
stw r3, 8(r0)
#endif
mtspr SPRN_SPRG_SCRATCH2, r10
/* fetch instruction from memory. */
mfspr r10, SPRN_SRR0
andis. r11, r10, 0x8000 /* Address >= 0x80000000 */
@ -543,6 +539,9 @@ FixupDAR:/* Entry point for dcbx workaround. */
mtspr SPRN_MD_TWC, r11 /* Load pte table base address */
mfspr r11, SPRN_MD_TWC /* ....and get the pte address */
lwz r11, 0(r11) /* Get the pte */
#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0) /* restore r3 from memory */
#endif
/* concat physical page address(r11) and page offset(r10) */
rlwimi r11, r10, 0, 20, 31
lwz r11,0(r11)
@ -563,15 +562,13 @@ FixupDAR:/* Entry point for dcbx workaround. */
beq+ 142f
cmpwi cr0, r10, 1964 /* Is icbi? */
beq+ 142f
141: b DARFixed /* Nope, go back to normal TLB processing */
141: mfspr r10,SPRN_SPRG_SCRATCH2
b DARFixed /* Nope, go back to normal TLB processing */
144: mfspr r10, SPRN_DSISR
rlwinm r10, r10,0,7,5 /* Clear store bit for buggy dcbst insn */
mtspr SPRN_DSISR, r10
142: /* continue, it was a dcbx, dcbi instruction. */
#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0) /* restore r3 from memory */
#endif
#ifndef NO_SELF_MODIFYING_CODE
andis. r10,r11,0x1f /* test if reg RA is r0 */
li r10,modified_instr@l
@ -590,6 +587,7 @@ modified_instr:
bne+ 143f
subf r10,r0,r10 /* r10=r10-r0, only if reg RA is r0 */
143: mtdar r10 /* store faulting EA in DAR */
mfspr r10,SPRN_SPRG_SCRATCH2
b DARFixed /* Go back to normal TLB handling */
#else
mfctr r10
@ -643,6 +641,7 @@ modified_instr:
mfdar r11
mtctr r11 /* restore ctr reg from DAR */
mtdar r10 /* save fault EA to DAR */
mfspr r10,SPRN_SPRG_SCRATCH2
b DARFixed /* Go back to normal TLB handling */
/* special handling for r10,r11 since these are modified already */