diff options
Diffstat (limited to 'arch/powerpc/kernel/idle_book3s.S')
-rw-r--r-- | arch/powerpc/kernel/idle_book3s.S | 148 |
1 files changed, 79 insertions, 69 deletions
diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index d32751994a62..c3f62c9ce740 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -50,28 +50,32 @@ _GLOBAL(isa300_idle_stop_mayloss) std r1,PACAR1(r13) mflr r4 mfcr r5 - /* use stack red zone rather than a new frame for saving regs */ - std r2,-8*0(r1) - std r14,-8*1(r1) - std r15,-8*2(r1) - std r16,-8*3(r1) - std r17,-8*4(r1) - std r18,-8*5(r1) - std r19,-8*6(r1) - std r20,-8*7(r1) - std r21,-8*8(r1) - std r22,-8*9(r1) - std r23,-8*10(r1) - std r24,-8*11(r1) - std r25,-8*12(r1) - std r26,-8*13(r1) - std r27,-8*14(r1) - std r28,-8*15(r1) - std r29,-8*16(r1) - std r30,-8*17(r1) - std r31,-8*18(r1) - std r4,-8*19(r1) - std r5,-8*20(r1) + /* + * Use the stack red zone rather than a new frame for saving regs since + * in the case of no GPR loss the wakeup code branches directly back to + * the caller without deallocating the stack frame first. + */ + std r2,-8*1(r1) + std r14,-8*2(r1) + std r15,-8*3(r1) + std r16,-8*4(r1) + std r17,-8*5(r1) + std r18,-8*6(r1) + std r19,-8*7(r1) + std r20,-8*8(r1) + std r21,-8*9(r1) + std r22,-8*10(r1) + std r23,-8*11(r1) + std r24,-8*12(r1) + std r25,-8*13(r1) + std r26,-8*14(r1) + std r27,-8*15(r1) + std r28,-8*16(r1) + std r29,-8*17(r1) + std r30,-8*18(r1) + std r31,-8*19(r1) + std r4,-8*20(r1) + std r5,-8*21(r1) /* 168 bytes */ PPC_STOP b . /* catch bugs */ @@ -87,8 +91,8 @@ _GLOBAL(isa300_idle_stop_mayloss) */ _GLOBAL(idle_return_gpr_loss) ld r1,PACAR1(r13) - ld r4,-8*19(r1) - ld r5,-8*20(r1) + ld r4,-8*20(r1) + ld r5,-8*21(r1) mtlr r4 mtcr r5 /* @@ -96,38 +100,40 @@ _GLOBAL(idle_return_gpr_loss) * from PACATOC. This could be avoided for that less common case * if KVM saved its r2. */ - ld r2,-8*0(r1) - ld r14,-8*1(r1) - ld r15,-8*2(r1) - ld r16,-8*3(r1) - ld r17,-8*4(r1) - ld r18,-8*5(r1) - ld r19,-8*6(r1) - ld r20,-8*7(r1) - ld r21,-8*8(r1) - ld r22,-8*9(r1) - ld r23,-8*10(r1) - ld r24,-8*11(r1) - ld r25,-8*12(r1) - ld r26,-8*13(r1) - ld r27,-8*14(r1) - ld r28,-8*15(r1) - ld r29,-8*16(r1) - ld r30,-8*17(r1) - ld r31,-8*18(r1) + ld r2,-8*1(r1) + ld r14,-8*2(r1) + ld r15,-8*3(r1) + ld r16,-8*4(r1) + ld r17,-8*5(r1) + ld r18,-8*6(r1) + ld r19,-8*7(r1) + ld r20,-8*8(r1) + ld r21,-8*9(r1) + ld r22,-8*10(r1) + ld r23,-8*11(r1) + ld r24,-8*12(r1) + ld r25,-8*13(r1) + ld r26,-8*14(r1) + ld r27,-8*15(r1) + ld r28,-8*16(r1) + ld r29,-8*17(r1) + ld r30,-8*18(r1) + ld r31,-8*19(r1) blr /* * This is the sequence required to execute idle instructions, as * specified in ISA v2.07 (and earlier). MSR[IR] and MSR[DR] must be 0. - * - * The 0(r1) slot is used to save r2 in isa206, so use that here. + * We have to store a GPR somewhere, ptesync, then reload it, and create + * a false dependency on the result of the load. It doesn't matter which + * GPR we store, or where we store it. We have already stored r2 to the + * stack at -8(r1) in isa206_idle_insn_mayloss, so use that. */ #define IDLE_STATE_ENTER_SEQ_NORET(IDLE_INST) \ /* Magic NAP/SLEEP/WINKLE mode enter sequence */ \ - std r2,0(r1); \ + std r2,-8(r1); \ ptesync; \ - ld r2,0(r1); \ + ld r2,-8(r1); \ 236: cmpd cr0,r2,r2; \ bne 236b; \ IDLE_INST; \ @@ -152,28 +158,32 @@ _GLOBAL(isa206_idle_insn_mayloss) std r1,PACAR1(r13) mflr r4 mfcr r5 - /* use stack red zone rather than a new frame for saving regs */ - std r2,-8*0(r1) - std r14,-8*1(r1) - std r15,-8*2(r1) - std r16,-8*3(r1) - std r17,-8*4(r1) - std r18,-8*5(r1) - std r19,-8*6(r1) - std r20,-8*7(r1) - std r21,-8*8(r1) - std r22,-8*9(r1) - std r23,-8*10(r1) - std r24,-8*11(r1) - std r25,-8*12(r1) - std r26,-8*13(r1) - std r27,-8*14(r1) - std r28,-8*15(r1) - std r29,-8*16(r1) - std r30,-8*17(r1) - std r31,-8*18(r1) - std r4,-8*19(r1) - std r5,-8*20(r1) + /* + * Use the stack red zone rather than a new frame for saving regs since + * in the case of no GPR loss the wakeup code branches directly back to + * the caller without deallocating the stack frame first. + */ + std r2,-8*1(r1) + std r14,-8*2(r1) + std r15,-8*3(r1) + std r16,-8*4(r1) + std r17,-8*5(r1) + std r18,-8*6(r1) + std r19,-8*7(r1) + std r20,-8*8(r1) + std r21,-8*9(r1) + std r22,-8*10(r1) + std r23,-8*11(r1) + std r24,-8*12(r1) + std r25,-8*13(r1) + std r26,-8*14(r1) + std r27,-8*15(r1) + std r28,-8*16(r1) + std r29,-8*17(r1) + std r30,-8*18(r1) + std r31,-8*19(r1) + std r4,-8*20(r1) + std r5,-8*21(r1) cmpwi r3,PNV_THREAD_NAP bne 1f IDLE_STATE_ENTER_SEQ_NORET(PPC_NAP) |