From 673b189a2e3353061fa8c49515d1014dab6ad9b9 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Tue, 5 Apr 2011 13:59:58 +1000 Subject: [PATCH] powerpc: Always use SPRN_SPRG_HSCRATCH0 when running in HV mode This uses feature sections to arrange that we always use HSPRG1 as the scratch register in the interrupt entry code rather than SPRG2 when we're running in hypervisor mode on POWER7. This will ensure that we don't trash the guest's SPRG2 when we are running KVM guests. To simplify the code, we define GET_SCRATCH0() and SET_SCRATCH0() macros like the GET_PACA/SET_PACA macros. Signed-off-by: Paul Mackerras Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/exception-64s.h | 15 ++++++------- arch/powerpc/include/asm/reg.h | 14 ++++++++++++ arch/powerpc/kernel/exceptions-64s.S | 26 +++++++++++----------- arch/powerpc/kvm/book3s_rmhandlers.S | 6 ++--- arch/powerpc/kvm/book3s_segment.S | 2 +- arch/powerpc/platforms/iseries/exception.S | 2 +- arch/powerpc/platforms/iseries/exception.h | 4 ++-- 7 files changed, 41 insertions(+), 28 deletions(-) diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index fb5b0af30fcf..d6b4849df9b1 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -60,16 +60,15 @@ #define EXC_HV H #define EXC_STD -#define __EXCEPTION_PROLOG_1(area, h) \ +#define EXCEPTION_PROLOG_1(area) \ GET_PACA(r13); \ std r9,area+EX_R9(r13); /* save r9 - r12 */ \ std r10,area+EX_R10(r13); \ std r11,area+EX_R11(r13); \ std r12,area+EX_R12(r13); \ - mfspr r9,SPRN_SPRG_##h##SCRATCH0; \ + GET_SCRATCH0(r9); \ std r9,area+EX_R13(r13); \ mfcr r9 -#define EXCEPTION_PROLOG_1(area, h) __EXCEPTION_PROLOG_1(area, h) #define __EXCEPTION_PROLOG_PSERIES_1(label, h) \ ld r12,PACAKBASE(r13); /* get high part of &label */ \ @@ -85,7 +84,7 @@ __EXCEPTION_PROLOG_PSERIES_1(label, h) #define EXCEPTION_PROLOG_PSERIES(area, label, h) \ - EXCEPTION_PROLOG_1(area, h); \ + EXCEPTION_PROLOG_1(area); \ EXCEPTION_PROLOG_PSERIES_1(label, h); /* @@ -156,7 +155,7 @@ label##_pSeries: \ HMT_MEDIUM; \ DO_KVM vec; \ - mtspr SPRN_SPRG_SCRATCH0,r13; /* save r13 */ \ + SET_SCRATCH0(r13); /* save r13 */ \ EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common, EXC_STD) #define STD_EXCEPTION_HV(loc, vec, label) \ @@ -165,13 +164,13 @@ label##_pSeries: \ label##_hv: \ HMT_MEDIUM; \ DO_KVM vec; \ - mtspr SPRN_SPRG_HSCRATCH0,r13;/* save r13 */ \ + SET_SCRATCH0(r13); /* save r13 */ \ EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common, EXC_HV) #define __MASKABLE_EXCEPTION_PSERIES(vec, label, h) \ HMT_MEDIUM; \ DO_KVM vec; \ - mtspr SPRN_SPRG_##h##SCRATCH0,r13; /* save r13 */ \ + SET_SCRATCH0(r13); /* save r13 */ \ GET_PACA(r13); \ std r9,PACA_EXGEN+EX_R9(r13); /* save r9, r10 */ \ std r10,PACA_EXGEN+EX_R10(r13); \ @@ -179,7 +178,7 @@ label##_hv: \ mfcr r9; \ cmpwi r10,0; \ beq masked_##h##interrupt; \ - mfspr r10,SPRN_SPRG_##h##SCRATCH0; \ + GET_SCRATCH0(r10); \ std r10,PACA_EXGEN+EX_R13(r13); \ std r11,PACA_EXGEN+EX_R11(r13); \ std r12,PACA_EXGEN+EX_R12(r13); \ diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index 13429a0eba09..76d7d5fea5be 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -802,6 +802,20 @@ FTR_SECTION_ELSE_NESTED(66); \ mtspr SPRN_SPRG_HPACA,rX; \ ALT_FTR_SECTION_END_NESTED_IFCLR(CPU_FTR_HVMODE_206, 66) + +#define GET_SCRATCH0(rX) \ + BEGIN_FTR_SECTION_NESTED(66); \ + mfspr rX,SPRN_SPRG_SCRATCH0; \ + FTR_SECTION_ELSE_NESTED(66); \ + mfspr rX,SPRN_SPRG_HSCRATCH0; \ + ALT_FTR_SECTION_END_NESTED_IFCLR(CPU_FTR_HVMODE_206, 66) + +#define SET_SCRATCH0(rX) \ + BEGIN_FTR_SECTION_NESTED(66); \ + mtspr SPRN_SPRG_SCRATCH0,rX; \ + FTR_SECTION_ELSE_NESTED(66); \ + mtspr SPRN_SPRG_HSCRATCH0,rX; \ + ALT_FTR_SECTION_END_NESTED_IFCLR(CPU_FTR_HVMODE_206, 66) #endif #ifdef CONFIG_PPC_BOOK3E_64 diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 805e20657868..e513c1d35b2a 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -43,7 +43,7 @@ __start_interrupts: _machine_check_pSeries: HMT_MEDIUM DO_KVM 0x200 - mtspr SPRN_SPRG_SCRATCH0,r13 /* save r13 */ + SET_SCRATCH0(r13) EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common, EXC_STD) . = 0x300 @@ -51,7 +51,7 @@ _machine_check_pSeries: data_access_pSeries: HMT_MEDIUM DO_KVM 0x300 - mtspr SPRN_SPRG_SCRATCH0,r13 + SET_SCRATCH0(r13) BEGIN_FTR_SECTION GET_PACA(r13) std r9,PACA_EXSLB+EX_R9(r13) @@ -67,7 +67,7 @@ BEGIN_FTR_SECTION std r11,PACA_EXGEN+EX_R11(r13) ld r11,PACA_EXSLB+EX_R9(r13) std r12,PACA_EXGEN+EX_R12(r13) - mfspr r12,SPRN_SPRG_SCRATCH0 + GET_SCRATCH0(r12) std r10,PACA_EXGEN+EX_R10(r13) std r11,PACA_EXGEN+EX_R9(r13) std r12,PACA_EXGEN+EX_R13(r13) @@ -81,7 +81,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_SLB) data_access_slb_pSeries: HMT_MEDIUM DO_KVM 0x380 - mtspr SPRN_SPRG_SCRATCH0,r13 + SET_SCRATCH0(r13) GET_PACA(r13) std r3,PACA_EXSLB+EX_R3(r13) mfspr r3,SPRN_DAR @@ -95,7 +95,7 @@ data_access_slb_pSeries: std r10,PACA_EXSLB+EX_R10(r13) std r11,PACA_EXSLB+EX_R11(r13) std r12,PACA_EXSLB+EX_R12(r13) - mfspr r10,SPRN_SPRG_SCRATCH0 + GET_SCRATCH0(r10) std r10,PACA_EXSLB+EX_R13(r13) mfspr r12,SPRN_SRR1 /* and SRR1 */ #ifndef CONFIG_RELOCATABLE @@ -120,7 +120,7 @@ data_access_slb_pSeries: instruction_access_slb_pSeries: HMT_MEDIUM DO_KVM 0x480 - mtspr SPRN_SPRG_SCRATCH0,r13 + SET_SCRATCH0(r13) GET_PACA(r13) std r3,PACA_EXSLB+EX_R3(r13) mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */ @@ -134,7 +134,7 @@ instruction_access_slb_pSeries: std r10,PACA_EXSLB+EX_R10(r13) std r11,PACA_EXSLB+EX_R11(r13) std r12,PACA_EXSLB+EX_R12(r13) - mfspr r10,SPRN_SPRG_SCRATCH0 + GET_SCRATCH0(r10) std r10,PACA_EXSLB+EX_R13(r13) mfspr r12,SPRN_SRR1 /* and SRR1 */ #ifndef CONFIG_RELOCATABLE @@ -272,7 +272,7 @@ masked_interrupt: rotldi r10,r10,16 mtspr SPRN_SRR1,r10 ld r10,PACA_EXGEN+EX_R10(r13) - mfspr r13,SPRN_SPRG_SCRATCH0 + GET_SCRATCH0(r13) rfid b . @@ -285,7 +285,7 @@ masked_Hinterrupt: rotldi r10,r10,16 mtspr SPRN_HSRR1,r10 ld r10,PACA_EXGEN+EX_R10(r13) - mfspr r13,SPRN_SPRG_HSCRATCH0 + GET_SCRATCH0(r13) hrfid b . @@ -293,7 +293,7 @@ masked_Hinterrupt: do_stab_bolted_pSeries: std r11,PACA_EXSLB+EX_R11(r13) std r12,PACA_EXSLB+EX_R12(r13) - mfspr r10,SPRN_SPRG_SCRATCH0 + GET_SCRATCH0(r10) std r10,PACA_EXSLB+EX_R13(r13) EXCEPTION_PROLOG_PSERIES_1(.do_stab_bolted, EXC_STD) @@ -305,14 +305,14 @@ do_stab_bolted_pSeries: .align 7 system_reset_fwnmi: HMT_MEDIUM - mtspr SPRN_SPRG_SCRATCH0,r13 /* save r13 */ + SET_SCRATCH0(r13) /* save r13 */ EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD) .globl machine_check_fwnmi .align 7 machine_check_fwnmi: HMT_MEDIUM - mtspr SPRN_SPRG_SCRATCH0,r13 /* save r13 */ + SET_SCRATCH0(r13) /* save r13 */ EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common, EXC_STD) #endif /* CONFIG_PPC_PSERIES */ @@ -327,7 +327,7 @@ slb_miss_user_pseries: std r10,PACA_EXGEN+EX_R10(r13) std r11,PACA_EXGEN+EX_R11(r13) std r12,PACA_EXGEN+EX_R12(r13) - mfspr r10,SPRG_SCRATCH0 + GET_SCRATCH0(r10) ld r11,PACA_EXSLB+EX_R9(r13) ld r12,PACA_EXSLB+EX_R3(r13) std r10,PACA_EXGEN+EX_R13(r13) diff --git a/arch/powerpc/kvm/book3s_rmhandlers.S b/arch/powerpc/kvm/book3s_rmhandlers.S index 046e1f3d4432..ae99af66ca34 100644 --- a/arch/powerpc/kvm/book3s_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_rmhandlers.S @@ -70,7 +70,7 @@ .global kvmppc_trampoline_\intno kvmppc_trampoline_\intno: - mtspr SPRN_SPRG_SCRATCH0, r13 /* Save r13 */ + SET_SCRATCH0(r13) /* Save r13 */ /* * First thing to do is to find out if we're coming @@ -89,7 +89,7 @@ kvmppc_trampoline_\intno: lwz r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13) mtcr r12 PPC_LL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13) - mfspr r13, SPRN_SPRG_SCRATCH0 /* r13 = original r13 */ + GET_SCRATCH0(r13) /* r13 = original r13 */ b kvmppc_resume_\intno /* Get back original handler */ /* Now we know we're handling a KVM guest */ @@ -157,7 +157,7 @@ kvmppc_handler_skip_ins: lwz r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13) mtcr r12 PPC_LL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13) - mfspr r13, SPRN_SPRG_SCRATCH0 + GET_SCRATCH0(r13) /* And get back into the code */ RFI diff --git a/arch/powerpc/kvm/book3s_segment.S b/arch/powerpc/kvm/book3s_segment.S index d842795d0f23..451264274b8c 100644 --- a/arch/powerpc/kvm/book3s_segment.S +++ b/arch/powerpc/kvm/book3s_segment.S @@ -168,7 +168,7 @@ kvmppc_handler_trampoline_exit: PPC_STL r4, (SHADOW_VCPU_OFF + SVCPU_SHADOW_SRR1)(r13) /* Get scratch'ed off registers */ - mfspr r9, SPRN_SPRG_SCRATCH0 + GET_SCRATCH0(r9) PPC_LL r8, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13) lwz r7, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13) diff --git a/arch/powerpc/platforms/iseries/exception.S b/arch/powerpc/platforms/iseries/exception.S index f7a487231a11..32a56c6dfa72 100644 --- a/arch/powerpc/platforms/iseries/exception.S +++ b/arch/powerpc/platforms/iseries/exception.S @@ -155,7 +155,7 @@ BEGIN_FTR_SECTION std r12,PACA_EXGEN+EX_R13(r13) EXCEPTION_PROLOG_ISERIES_1 FTR_SECTION_ELSE - EXCEPTION_PROLOG_1(PACA_EXGEN, EXC_STD) + EXCEPTION_PROLOG_1(PACA_EXGEN) EXCEPTION_PROLOG_ISERIES_1 ALT_FTR_SECTION_END_IFCLR(CPU_FTR_SLB) b data_access_common diff --git a/arch/powerpc/platforms/iseries/exception.h b/arch/powerpc/platforms/iseries/exception.h index 57127d805fe3..bae3fba5ad8e 100644 --- a/arch/powerpc/platforms/iseries/exception.h +++ b/arch/powerpc/platforms/iseries/exception.h @@ -39,7 +39,7 @@ label##_iSeries: \ HMT_MEDIUM; \ mtspr SPRN_SPRG_SCRATCH0,r13; /* save r13 */ \ - EXCEPTION_PROLOG_1(area, EXC_STD); \ + EXCEPTION_PROLOG_1(area); \ EXCEPTION_PROLOG_ISERIES_1; \ b label##_common @@ -48,7 +48,7 @@ label##_iSeries: \ label##_iSeries: \ HMT_MEDIUM; \ mtspr SPRN_SPRG_SCRATCH0,r13; /* save r13 */ \ - EXCEPTION_PROLOG_1(PACA_EXGEN, EXC_STD); \ + EXCEPTION_PROLOG_1(PACA_EXGEN); \ lbz r10,PACASOFTIRQEN(r13); \ cmpwi 0,r10,0; \ beq- label##_iSeries_masked; \ -- 2.20.1