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- /*
- * This file contains the 64-bit "server" PowerPC variant
- * of the low level exception handling including exception
- * vectors, exception return, part of the slb and stab
- * handling and other fixed offset specific things.
- *
- * This file is meant to be #included from head_64.S due to
- * position dependent assembly.
- *
- * Most of this originates from head_64.S and thus has the same
- * copyright history.
- *
- */
- #include <asm/hw_irq.h>
- #include <asm/exception-64s.h>
- #include <asm/ptrace.h>
- #include <asm/cpuidle.h>
- /*
- * We layout physical memory as follows:
- * 0x0000 - 0x00ff : Secondary processor spin code
- * 0x0100 - 0x17ff : pSeries Interrupt prologs
- * 0x1800 - 0x4000 : interrupt support common interrupt prologs
- * 0x4000 - 0x5fff : pSeries interrupts with IR=1,DR=1
- * 0x6000 - 0x6fff : more interrupt support including for IR=1,DR=1
- * 0x7000 - 0x7fff : FWNMI data area
- * 0x8000 - 0x8fff : Initial (CPU0) segment table
- * 0x9000 - : Early init and support code
- */
- /* Syscall routine is used twice, in reloc-off and reloc-on paths */
- #define SYSCALL_PSERIES_1 \
- BEGIN_FTR_SECTION \
- cmpdi r0,0x1ebe ; \
- beq- 1f ; \
- END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) \
- mr r9,r13 ; \
- GET_PACA(r13) ; \
- mfspr r11,SPRN_SRR0 ; \
- 0:
- #define SYSCALL_PSERIES_2_RFID \
- mfspr r12,SPRN_SRR1 ; \
- ld r10,PACAKBASE(r13) ; \
- LOAD_HANDLER(r10, system_call_entry) ; \
- mtspr SPRN_SRR0,r10 ; \
- ld r10,PACAKMSR(r13) ; \
- mtspr SPRN_SRR1,r10 ; \
- rfid ; \
- b . ; /* prevent speculative execution */
- #define SYSCALL_PSERIES_3 \
- /* Fast LE/BE switch system call */ \
- 1: mfspr r12,SPRN_SRR1 ; \
- xori r12,r12,MSR_LE ; \
- mtspr SPRN_SRR1,r12 ; \
- rfid ; /* return to userspace */ \
- b . ; /* prevent speculative execution */
- #if defined(CONFIG_RELOCATABLE)
- /*
- * We can't branch directly so we do it via the CTR which
- * is volatile across system calls.
- */
- #define SYSCALL_PSERIES_2_DIRECT \
- mflr r10 ; \
- ld r12,PACAKBASE(r13) ; \
- LOAD_HANDLER(r12, system_call_entry) ; \
- mtctr r12 ; \
- mfspr r12,SPRN_SRR1 ; \
- /* Re-use of r13... No spare regs to do this */ \
- li r13,MSR_RI ; \
- mtmsrd r13,1 ; \
- GET_PACA(r13) ; /* get r13 back */ \
- bctr ;
- #else
- /* We can branch directly */
- #define SYSCALL_PSERIES_2_DIRECT \
- mfspr r12,SPRN_SRR1 ; \
- li r10,MSR_RI ; \
- mtmsrd r10,1 ; /* Set RI (EE=0) */ \
- b system_call_common ;
- #endif
- /*
- * This is the start of the interrupt handlers for pSeries
- * This code runs with relocation off.
- * Code from here to __end_interrupts gets copied down to real
- * address 0x100 when we are running a relocatable kernel.
- * Therefore any relative branches in this section must only
- * branch to labels in this section.
- */
- . = 0x100
- .globl __start_interrupts
- __start_interrupts:
- .globl system_reset_pSeries;
- system_reset_pSeries:
- HMT_MEDIUM_PPR_DISCARD
- SET_SCRATCH0(r13)
- #ifdef CONFIG_PPC_P7_NAP
- BEGIN_FTR_SECTION
- /* Running native on arch 2.06 or later, check if we are
- * waking up from nap/sleep/winkle.
- */
- mfspr r13,SPRN_SRR1
- rlwinm. r13,r13,47-31,30,31
- beq 9f
- cmpwi cr3,r13,2
- /*
- * Check if last bit of HSPGR0 is set. This indicates whether we are
- * waking up from winkle.
- */
- GET_PACA(r13)
- clrldi r5,r13,63
- clrrdi r13,r13,1
- cmpwi cr4,r5,1
- mtspr SPRN_HSPRG0,r13
- lbz r0,PACA_THREAD_IDLE_STATE(r13)
- cmpwi cr2,r0,PNV_THREAD_NAP
- bgt cr2,8f /* Either sleep or Winkle */
- /* Waking up from nap should not cause hypervisor state loss */
- bgt cr3,.
- /* Waking up from nap */
- li r0,PNV_THREAD_RUNNING
- stb r0,PACA_THREAD_IDLE_STATE(r13) /* Clear thread state */
- #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
- li r0,KVM_HWTHREAD_IN_KERNEL
- stb r0,HSTATE_HWTHREAD_STATE(r13)
- /* Order setting hwthread_state vs. testing hwthread_req */
- sync
- lbz r0,HSTATE_HWTHREAD_REQ(r13)
- cmpwi r0,0
- beq 1f
- b kvm_start_guest
- 1:
- #endif
- /* Return SRR1 from power7_nap() */
- mfspr r3,SPRN_SRR1
- beq cr3,2f
- b power7_wakeup_noloss
- 2: b power7_wakeup_loss
- /* Fast Sleep wakeup on PowerNV */
- 8: GET_PACA(r13)
- b power7_wakeup_tb_loss
- 9:
- END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
- #endif /* CONFIG_PPC_P7_NAP */
- EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
- NOTEST, 0x100)
- . = 0x200
- machine_check_pSeries_1:
- /* This is moved out of line as it can be patched by FW, but
- * some code path might still want to branch into the original
- * vector
- */
- HMT_MEDIUM_PPR_DISCARD
- SET_SCRATCH0(r13) /* save r13 */
- #ifdef CONFIG_PPC_P7_NAP
- BEGIN_FTR_SECTION
- /* Running native on arch 2.06 or later, check if we are
- * waking up from nap. We only handle no state loss and
- * supervisor state loss. We do -not- handle hypervisor
- * state loss at this time.
- */
- mfspr r13,SPRN_SRR1
- rlwinm. r13,r13,47-31,30,31
- OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
- beq 9f
- mfspr r13,SPRN_SRR1
- rlwinm. r13,r13,47-31,30,31
- /* waking up from powersave (nap) state */
- cmpwi cr1,r13,2
- /* Total loss of HV state is fatal. let's just stay stuck here */
- OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
- bgt cr1,.
- 9:
- OPT_SET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
- END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
- #endif /* CONFIG_PPC_P7_NAP */
- EXCEPTION_PROLOG_0(PACA_EXMC)
- BEGIN_FTR_SECTION
- b machine_check_pSeries_early
- FTR_SECTION_ELSE
- b machine_check_pSeries_0
- ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
- . = 0x300
- .globl data_access_pSeries
- data_access_pSeries:
- HMT_MEDIUM_PPR_DISCARD
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common, EXC_STD,
- KVMTEST, 0x300)
- . = 0x380
- .globl data_access_slb_pSeries
- data_access_slb_pSeries:
- HMT_MEDIUM_PPR_DISCARD
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x380)
- std r3,PACA_EXSLB+EX_R3(r13)
- mfspr r3,SPRN_DAR
- #ifdef __DISABLED__
- /* Keep that around for when we re-implement dynamic VSIDs */
- cmpdi r3,0
- bge slb_miss_user_pseries
- #endif /* __DISABLED__ */
- mfspr r12,SPRN_SRR1
- #ifndef CONFIG_RELOCATABLE
- b slb_miss_realmode
- #else
- /*
- * We can't just use a direct branch to slb_miss_realmode
- * because the distance from here to there depends on where
- * the kernel ends up being put.
- */
- mfctr r11
- ld r10,PACAKBASE(r13)
- LOAD_HANDLER(r10, slb_miss_realmode)
- mtctr r10
- bctr
- #endif
- STD_EXCEPTION_PSERIES(0x400, 0x400, instruction_access)
- . = 0x480
- .globl instruction_access_slb_pSeries
- instruction_access_slb_pSeries:
- HMT_MEDIUM_PPR_DISCARD
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
- std r3,PACA_EXSLB+EX_R3(r13)
- mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
- #ifdef __DISABLED__
- /* Keep that around for when we re-implement dynamic VSIDs */
- cmpdi r3,0
- bge slb_miss_user_pseries
- #endif /* __DISABLED__ */
- mfspr r12,SPRN_SRR1
- #ifndef CONFIG_RELOCATABLE
- b slb_miss_realmode
- #else
- mfctr r11
- ld r10,PACAKBASE(r13)
- LOAD_HANDLER(r10, slb_miss_realmode)
- mtctr r10
- bctr
- #endif
- /* We open code these as we can't have a ". = x" (even with
- * x = "." within a feature section
- */
- . = 0x500;
- .globl hardware_interrupt_pSeries;
- .globl hardware_interrupt_hv;
- hardware_interrupt_pSeries:
- hardware_interrupt_hv:
- HMT_MEDIUM_PPR_DISCARD
- BEGIN_FTR_SECTION
- _MASKABLE_EXCEPTION_PSERIES(0x502, hardware_interrupt,
- EXC_HV, SOFTEN_TEST_HV)
- KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x502)
- FTR_SECTION_ELSE
- _MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt,
- EXC_STD, SOFTEN_TEST_HV_201)
- KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x500)
- ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
- STD_EXCEPTION_PSERIES(0x600, 0x600, alignment)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x600)
- STD_EXCEPTION_PSERIES(0x700, 0x700, program_check)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x700)
- STD_EXCEPTION_PSERIES(0x800, 0x800, fp_unavailable)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x800)
- . = 0x900
- .globl decrementer_pSeries
- decrementer_pSeries:
- _MASKABLE_EXCEPTION_PSERIES(0x900, decrementer, EXC_STD, SOFTEN_TEST_PR)
- STD_EXCEPTION_HV(0x980, 0x982, hdecrementer)
- MASKABLE_EXCEPTION_PSERIES(0xa00, 0xa00, doorbell_super)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xa00)
- STD_EXCEPTION_PSERIES(0xb00, 0xb00, trap_0b)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xb00)
- . = 0xc00
- .globl system_call_pSeries
- system_call_pSeries:
- /*
- * If CONFIG_KVM_BOOK3S_64_HANDLER is set, save the PPR (on systems
- * that support it) before changing to HMT_MEDIUM. That allows the KVM
- * code to save that value into the guest state (it is the guest's PPR
- * value). Otherwise just change to HMT_MEDIUM as userspace has
- * already saved the PPR.
- */
- #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
- SET_SCRATCH0(r13)
- GET_PACA(r13)
- std r9,PACA_EXGEN+EX_R9(r13)
- OPT_GET_SPR(r9, SPRN_PPR, CPU_FTR_HAS_PPR);
- HMT_MEDIUM;
- std r10,PACA_EXGEN+EX_R10(r13)
- OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r9, CPU_FTR_HAS_PPR);
- mfcr r9
- KVMTEST(0xc00)
- GET_SCRATCH0(r13)
- #else
- HMT_MEDIUM;
- #endif
- SYSCALL_PSERIES_1
- SYSCALL_PSERIES_2_RFID
- SYSCALL_PSERIES_3
- KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xc00)
- STD_EXCEPTION_PSERIES(0xd00, 0xd00, single_step)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xd00)
- /* At 0xe??? we have a bunch of hypervisor exceptions, we branch
- * out of line to handle them
- */
- . = 0xe00
- hv_data_storage_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b h_data_storage_hv
- . = 0xe20
- hv_instr_storage_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b h_instr_storage_hv
- . = 0xe40
- emulation_assist_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b emulation_assist_hv
- . = 0xe60
- hv_exception_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b hmi_exception_early
- . = 0xe80
- hv_doorbell_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b h_doorbell_hv
- /* We need to deal with the Altivec unavailable exception
- * here which is at 0xf20, thus in the middle of the
- * prolog code of the PerformanceMonitor one. A little
- * trickery is thus necessary
- */
- . = 0xf00
- performance_monitor_pseries_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b performance_monitor_pSeries
- . = 0xf20
- altivec_unavailable_pseries_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b altivec_unavailable_pSeries
- . = 0xf40
- vsx_unavailable_pseries_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b vsx_unavailable_pSeries
- . = 0xf60
- facility_unavailable_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b facility_unavailable_pSeries
- . = 0xf80
- hv_facility_unavailable_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b facility_unavailable_hv
- #ifdef CONFIG_CBE_RAS
- STD_EXCEPTION_HV(0x1200, 0x1202, cbe_system_error)
- KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1202)
- #endif /* CONFIG_CBE_RAS */
- STD_EXCEPTION_PSERIES(0x1300, 0x1300, instruction_breakpoint)
- KVM_HANDLER_PR_SKIP(PACA_EXGEN, EXC_STD, 0x1300)
- . = 0x1500
- .global denorm_exception_hv
- denorm_exception_hv:
- HMT_MEDIUM_PPR_DISCARD
- mtspr SPRN_SPRG_HSCRATCH0,r13
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0x1500)
- #ifdef CONFIG_PPC_DENORMALISATION
- mfspr r10,SPRN_HSRR1
- mfspr r11,SPRN_HSRR0 /* save HSRR0 */
- andis. r10,r10,(HSRR1_DENORM)@h /* denorm? */
- addi r11,r11,-4 /* HSRR0 is next instruction */
- bne+ denorm_assist
- #endif
- KVMTEST(0x1500)
- EXCEPTION_PROLOG_PSERIES_1(denorm_common, EXC_HV)
- KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x1500)
- #ifdef CONFIG_CBE_RAS
- STD_EXCEPTION_HV(0x1600, 0x1602, cbe_maintenance)
- KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1602)
- #endif /* CONFIG_CBE_RAS */
- STD_EXCEPTION_PSERIES(0x1700, 0x1700, altivec_assist)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x1700)
- #ifdef CONFIG_CBE_RAS
- STD_EXCEPTION_HV(0x1800, 0x1802, cbe_thermal)
- KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1802)
- #else
- . = 0x1800
- #endif /* CONFIG_CBE_RAS */
- /*** Out of line interrupts support ***/
- .align 7
- /* moved from 0x200 */
- machine_check_pSeries_early:
- BEGIN_FTR_SECTION
- EXCEPTION_PROLOG_1(PACA_EXMC, NOTEST, 0x200)
- /*
- * Register contents:
- * R13 = PACA
- * R9 = CR
- * Original R9 to R13 is saved on PACA_EXMC
- *
- * Switch to mc_emergency stack and handle re-entrancy (we limit
- * the nested MCE upto level 4 to avoid stack overflow).
- * Save MCE registers srr1, srr0, dar and dsisr and then set ME=1
- *
- * We use paca->in_mce to check whether this is the first entry or
- * nested machine check. We increment paca->in_mce to track nested
- * machine checks.
- *
- * If this is the first entry then set stack pointer to
- * paca->mc_emergency_sp, otherwise r1 is already pointing to
- * stack frame on mc_emergency stack.
- *
- * NOTE: We are here with MSR_ME=0 (off), which means we risk a
- * checkstop if we get another machine check exception before we do
- * rfid with MSR_ME=1.
- */
- mr r11,r1 /* Save r1 */
- lhz r10,PACA_IN_MCE(r13)
- cmpwi r10,0 /* Are we in nested machine check */
- bne 0f /* Yes, we are. */
- /* First machine check entry */
- ld r1,PACAMCEMERGSP(r13) /* Use MC emergency stack */
- 0: subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
- addi r10,r10,1 /* increment paca->in_mce */
- sth r10,PACA_IN_MCE(r13)
- /* Limit nested MCE to level 4 to avoid stack overflow */
- cmpwi r10,4
- bgt 2f /* Check if we hit limit of 4 */
- std r11,GPR1(r1) /* Save r1 on the stack. */
- std r11,0(r1) /* make stack chain pointer */
- mfspr r11,SPRN_SRR0 /* Save SRR0 */
- std r11,_NIP(r1)
- mfspr r11,SPRN_SRR1 /* Save SRR1 */
- std r11,_MSR(r1)
- mfspr r11,SPRN_DAR /* Save DAR */
- std r11,_DAR(r1)
- mfspr r11,SPRN_DSISR /* Save DSISR */
- std r11,_DSISR(r1)
- std r9,_CCR(r1) /* Save CR in stackframe */
- /* Save r9 through r13 from EXMC save area to stack frame. */
- EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
- mfmsr r11 /* get MSR value */
- ori r11,r11,MSR_ME /* turn on ME bit */
- ori r11,r11,MSR_RI /* turn on RI bit */
- ld r12,PACAKBASE(r13) /* get high part of &label */
- LOAD_HANDLER(r12, machine_check_handle_early)
- 1: mtspr SPRN_SRR0,r12
- mtspr SPRN_SRR1,r11
- rfid
- b . /* prevent speculative execution */
- 2:
- /* Stack overflow. Stay on emergency stack and panic.
- * Keep the ME bit off while panic-ing, so that if we hit
- * another machine check we checkstop.
- */
- addi r1,r1,INT_FRAME_SIZE /* go back to previous stack frame */
- ld r11,PACAKMSR(r13)
- ld r12,PACAKBASE(r13)
- LOAD_HANDLER(r12, unrecover_mce)
- li r10,MSR_ME
- andc r11,r11,r10 /* Turn off MSR_ME */
- b 1b
- b . /* prevent speculative execution */
- END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
- machine_check_pSeries:
- .globl machine_check_fwnmi
- machine_check_fwnmi:
- HMT_MEDIUM_PPR_DISCARD
- SET_SCRATCH0(r13) /* save r13 */
- EXCEPTION_PROLOG_0(PACA_EXMC)
- machine_check_pSeries_0:
- EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST, 0x200)
- EXCEPTION_PROLOG_PSERIES_1(machine_check_common, EXC_STD)
- KVM_HANDLER_SKIP(PACA_EXMC, EXC_STD, 0x200)
- KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x300)
- KVM_HANDLER_SKIP(PACA_EXSLB, EXC_STD, 0x380)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x400)
- KVM_HANDLER_PR(PACA_EXSLB, EXC_STD, 0x480)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x900)
- KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x982)
- #ifdef CONFIG_PPC_DENORMALISATION
- denorm_assist:
- BEGIN_FTR_SECTION
- /*
- * To denormalise we need to move a copy of the register to itself.
- * For POWER6 do that here for all FP regs.
- */
- mfmsr r10
- ori r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
- xori r10,r10,(MSR_FE0|MSR_FE1)
- mtmsrd r10
- sync
- #define FMR2(n) fmr (n), (n) ; fmr n+1, n+1
- #define FMR4(n) FMR2(n) ; FMR2(n+2)
- #define FMR8(n) FMR4(n) ; FMR4(n+4)
- #define FMR16(n) FMR8(n) ; FMR8(n+8)
- #define FMR32(n) FMR16(n) ; FMR16(n+16)
- FMR32(0)
- FTR_SECTION_ELSE
- /*
- * To denormalise we need to move a copy of the register to itself.
- * For POWER7 do that here for the first 32 VSX registers only.
- */
- mfmsr r10
- oris r10,r10,MSR_VSX@h
- mtmsrd r10
- sync
- #define XVCPSGNDP2(n) XVCPSGNDP(n,n,n) ; XVCPSGNDP(n+1,n+1,n+1)
- #define XVCPSGNDP4(n) XVCPSGNDP2(n) ; XVCPSGNDP2(n+2)
- #define XVCPSGNDP8(n) XVCPSGNDP4(n) ; XVCPSGNDP4(n+4)
- #define XVCPSGNDP16(n) XVCPSGNDP8(n) ; XVCPSGNDP8(n+8)
- #define XVCPSGNDP32(n) XVCPSGNDP16(n) ; XVCPSGNDP16(n+16)
- XVCPSGNDP32(0)
- ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
- BEGIN_FTR_SECTION
- b denorm_done
- END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
- /*
- * To denormalise we need to move a copy of the register to itself.
- * For POWER8 we need to do that for all 64 VSX registers
- */
- XVCPSGNDP32(32)
- denorm_done:
- mtspr SPRN_HSRR0,r11
- mtcrf 0x80,r9
- ld r9,PACA_EXGEN+EX_R9(r13)
- RESTORE_PPR_PACA(PACA_EXGEN, r10)
- BEGIN_FTR_SECTION
- ld r10,PACA_EXGEN+EX_CFAR(r13)
- mtspr SPRN_CFAR,r10
- END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
- ld r10,PACA_EXGEN+EX_R10(r13)
- ld r11,PACA_EXGEN+EX_R11(r13)
- ld r12,PACA_EXGEN+EX_R12(r13)
- ld r13,PACA_EXGEN+EX_R13(r13)
- HRFID
- b .
- #endif
- .align 7
- /* moved from 0xe00 */
- STD_EXCEPTION_HV_OOL(0xe02, h_data_storage)
- KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0xe02)
- STD_EXCEPTION_HV_OOL(0xe22, h_instr_storage)
- KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe22)
- STD_EXCEPTION_HV_OOL(0xe42, emulation_assist)
- KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe42)
- MASKABLE_EXCEPTION_HV_OOL(0xe62, hmi_exception)
- KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe62)
- MASKABLE_EXCEPTION_HV_OOL(0xe82, h_doorbell)
- KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe82)
- /* moved from 0xf00 */
- STD_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf00)
- STD_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf20)
- STD_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf40)
- STD_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
- KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf60)
- STD_EXCEPTION_HV_OOL(0xf82, facility_unavailable)
- KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xf82)
- /*
- * An interrupt came in while soft-disabled. We set paca->irq_happened, then:
- * - If it was a decrementer interrupt, we bump the dec to max and and return.
- * - If it was a doorbell we return immediately since doorbells are edge
- * triggered and won't automatically refire.
- * - If it was a HMI we return immediately since we handled it in realmode
- * and it won't refire.
- * - else we hard disable and return.
- * This is called with r10 containing the value to OR to the paca field.
- */
- #define MASKED_INTERRUPT(_H) \
- masked_##_H##interrupt: \
- std r11,PACA_EXGEN+EX_R11(r13); \
- lbz r11,PACAIRQHAPPENED(r13); \
- or r11,r11,r10; \
- stb r11,PACAIRQHAPPENED(r13); \
- cmpwi r10,PACA_IRQ_DEC; \
- bne 1f; \
- lis r10,0x7fff; \
- ori r10,r10,0xffff; \
- mtspr SPRN_DEC,r10; \
- b 2f; \
- 1: cmpwi r10,PACA_IRQ_DBELL; \
- beq 2f; \
- cmpwi r10,PACA_IRQ_HMI; \
- beq 2f; \
- mfspr r10,SPRN_##_H##SRR1; \
- rldicl r10,r10,48,1; /* clear MSR_EE */ \
- rotldi r10,r10,16; \
- mtspr SPRN_##_H##SRR1,r10; \
- 2: mtcrf 0x80,r9; \
- ld r9,PACA_EXGEN+EX_R9(r13); \
- ld r10,PACA_EXGEN+EX_R10(r13); \
- ld r11,PACA_EXGEN+EX_R11(r13); \
- GET_SCRATCH0(r13); \
- ##_H##rfid; \
- b .
-
- MASKED_INTERRUPT()
- MASKED_INTERRUPT(H)
- /*
- * Called from arch_local_irq_enable when an interrupt needs
- * to be resent. r3 contains 0x500, 0x900, 0xa00 or 0xe80 to indicate
- * which kind of interrupt. MSR:EE is already off. We generate a
- * stackframe like if a real interrupt had happened.
- *
- * Note: While MSR:EE is off, we need to make sure that _MSR
- * in the generated frame has EE set to 1 or the exception
- * handler will not properly re-enable them.
- */
- _GLOBAL(__replay_interrupt)
- /* We are going to jump to the exception common code which
- * will retrieve various register values from the PACA which
- * we don't give a damn about, so we don't bother storing them.
- */
- mfmsr r12
- mflr r11
- mfcr r9
- ori r12,r12,MSR_EE
- cmpwi r3,0x900
- beq decrementer_common
- cmpwi r3,0x500
- beq hardware_interrupt_common
- BEGIN_FTR_SECTION
- cmpwi r3,0xe80
- beq h_doorbell_common
- FTR_SECTION_ELSE
- cmpwi r3,0xa00
- beq doorbell_super_common
- ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
- blr
- #ifdef CONFIG_PPC_PSERIES
- /*
- * Vectors for the FWNMI option. Share common code.
- */
- .globl system_reset_fwnmi
- .align 7
- system_reset_fwnmi:
- HMT_MEDIUM_PPR_DISCARD
- SET_SCRATCH0(r13) /* save r13 */
- EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
- NOTEST, 0x100)
- #endif /* CONFIG_PPC_PSERIES */
- #ifdef __DISABLED__
- /*
- * This is used for when the SLB miss handler has to go virtual,
- * which doesn't happen for now anymore but will once we re-implement
- * dynamic VSIDs for shared page tables
- */
- 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)
- GET_SCRATCH0(r10)
- ld r11,PACA_EXSLB+EX_R9(r13)
- ld r12,PACA_EXSLB+EX_R3(r13)
- std r10,PACA_EXGEN+EX_R13(r13)
- std r11,PACA_EXGEN+EX_R9(r13)
- std r12,PACA_EXGEN+EX_R3(r13)
- clrrdi r12,r13,32
- mfmsr r10
- mfspr r11,SRR0 /* save SRR0 */
- ori r12,r12,slb_miss_user_common@l /* virt addr of handler */
- ori r10,r10,MSR_IR|MSR_DR|MSR_RI
- mtspr SRR0,r12
- mfspr r12,SRR1 /* and SRR1 */
- mtspr SRR1,r10
- rfid
- b . /* prevent spec. execution */
- #endif /* __DISABLED__ */
- #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
- kvmppc_skip_interrupt:
- /*
- * Here all GPRs are unchanged from when the interrupt happened
- * except for r13, which is saved in SPRG_SCRATCH0.
- */
- mfspr r13, SPRN_SRR0
- addi r13, r13, 4
- mtspr SPRN_SRR0, r13
- GET_SCRATCH0(r13)
- rfid
- b .
- kvmppc_skip_Hinterrupt:
- /*
- * Here all GPRs are unchanged from when the interrupt happened
- * except for r13, which is saved in SPRG_SCRATCH0.
- */
- mfspr r13, SPRN_HSRR0
- addi r13, r13, 4
- mtspr SPRN_HSRR0, r13
- GET_SCRATCH0(r13)
- hrfid
- b .
- #endif
- /*
- * Code from here down to __end_handlers is invoked from the
- * exception prologs above. Because the prologs assemble the
- * addresses of these handlers using the LOAD_HANDLER macro,
- * which uses an ori instruction, these handlers must be in
- * the first 64k of the kernel image.
- */
- /*** Common interrupt handlers ***/
- STD_EXCEPTION_COMMON(0x100, system_reset, system_reset_exception)
- STD_EXCEPTION_COMMON_ASYNC(0x500, hardware_interrupt, do_IRQ)
- STD_EXCEPTION_COMMON_ASYNC(0x900, decrementer, timer_interrupt)
- STD_EXCEPTION_COMMON(0x980, hdecrementer, hdec_interrupt)
- #ifdef CONFIG_PPC_DOORBELL
- STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, doorbell_exception)
- #else
- STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, unknown_exception)
- #endif
- STD_EXCEPTION_COMMON(0xb00, trap_0b, unknown_exception)
- STD_EXCEPTION_COMMON(0xd00, single_step, single_step_exception)
- STD_EXCEPTION_COMMON(0xe00, trap_0e, unknown_exception)
- STD_EXCEPTION_COMMON(0xe40, emulation_assist, emulation_assist_interrupt)
- STD_EXCEPTION_COMMON_ASYNC(0xe60, hmi_exception, handle_hmi_exception)
- #ifdef CONFIG_PPC_DOORBELL
- STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, doorbell_exception)
- #else
- STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, unknown_exception)
- #endif
- STD_EXCEPTION_COMMON_ASYNC(0xf00, performance_monitor, performance_monitor_exception)
- STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, instruction_breakpoint_exception)
- STD_EXCEPTION_COMMON(0x1502, denorm, unknown_exception)
- #ifdef CONFIG_ALTIVEC
- STD_EXCEPTION_COMMON(0x1700, altivec_assist, altivec_assist_exception)
- #else
- STD_EXCEPTION_COMMON(0x1700, altivec_assist, unknown_exception)
- #endif
- #ifdef CONFIG_CBE_RAS
- STD_EXCEPTION_COMMON(0x1200, cbe_system_error, cbe_system_error_exception)
- STD_EXCEPTION_COMMON(0x1600, cbe_maintenance, cbe_maintenance_exception)
- STD_EXCEPTION_COMMON(0x1800, cbe_thermal, cbe_thermal_exception)
- #endif /* CONFIG_CBE_RAS */
- /*
- * Relocation-on interrupts: A subset of the interrupts can be delivered
- * with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
- * it. Addresses are the same as the original interrupt addresses, but
- * offset by 0xc000000000004000.
- * It's impossible to receive interrupts below 0x300 via this mechanism.
- * KVM: None of these traps are from the guest ; anything that escalated
- * to HV=1 from HV=0 is delivered via real mode handlers.
- */
- /*
- * This uses the standard macro, since the original 0x300 vector
- * only has extra guff for STAB-based processors -- which never
- * come here.
- */
- STD_RELON_EXCEPTION_PSERIES(0x4300, 0x300, data_access)
- . = 0x4380
- .globl data_access_slb_relon_pSeries
- data_access_slb_relon_pSeries:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
- std r3,PACA_EXSLB+EX_R3(r13)
- mfspr r3,SPRN_DAR
- mfspr r12,SPRN_SRR1
- #ifndef CONFIG_RELOCATABLE
- b slb_miss_realmode
- #else
- /*
- * We can't just use a direct branch to slb_miss_realmode
- * because the distance from here to there depends on where
- * the kernel ends up being put.
- */
- mfctr r11
- ld r10,PACAKBASE(r13)
- LOAD_HANDLER(r10, slb_miss_realmode)
- mtctr r10
- bctr
- #endif
- STD_RELON_EXCEPTION_PSERIES(0x4400, 0x400, instruction_access)
- . = 0x4480
- .globl instruction_access_slb_relon_pSeries
- instruction_access_slb_relon_pSeries:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXSLB)
- EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
- std r3,PACA_EXSLB+EX_R3(r13)
- mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
- mfspr r12,SPRN_SRR1
- #ifndef CONFIG_RELOCATABLE
- b slb_miss_realmode
- #else
- mfctr r11
- ld r10,PACAKBASE(r13)
- LOAD_HANDLER(r10, slb_miss_realmode)
- mtctr r10
- bctr
- #endif
- . = 0x4500
- .globl hardware_interrupt_relon_pSeries;
- .globl hardware_interrupt_relon_hv;
- hardware_interrupt_relon_pSeries:
- hardware_interrupt_relon_hv:
- BEGIN_FTR_SECTION
- _MASKABLE_RELON_EXCEPTION_PSERIES(0x502, hardware_interrupt, EXC_HV, SOFTEN_TEST_HV)
- FTR_SECTION_ELSE
- _MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt, EXC_STD, SOFTEN_TEST_PR)
- ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
- STD_RELON_EXCEPTION_PSERIES(0x4600, 0x600, alignment)
- STD_RELON_EXCEPTION_PSERIES(0x4700, 0x700, program_check)
- STD_RELON_EXCEPTION_PSERIES(0x4800, 0x800, fp_unavailable)
- MASKABLE_RELON_EXCEPTION_PSERIES(0x4900, 0x900, decrementer)
- STD_RELON_EXCEPTION_HV(0x4980, 0x982, hdecrementer)
- MASKABLE_RELON_EXCEPTION_PSERIES(0x4a00, 0xa00, doorbell_super)
- STD_RELON_EXCEPTION_PSERIES(0x4b00, 0xb00, trap_0b)
- . = 0x4c00
- .globl system_call_relon_pSeries
- system_call_relon_pSeries:
- HMT_MEDIUM
- SYSCALL_PSERIES_1
- SYSCALL_PSERIES_2_DIRECT
- SYSCALL_PSERIES_3
- STD_RELON_EXCEPTION_PSERIES(0x4d00, 0xd00, single_step)
- . = 0x4e00
- b . /* Can't happen, see v2.07 Book III-S section 6.5 */
- . = 0x4e20
- b . /* Can't happen, see v2.07 Book III-S section 6.5 */
- . = 0x4e40
- emulation_assist_relon_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b emulation_assist_relon_hv
- . = 0x4e60
- b . /* Can't happen, see v2.07 Book III-S section 6.5 */
- . = 0x4e80
- h_doorbell_relon_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b h_doorbell_relon_hv
- . = 0x4f00
- performance_monitor_relon_pseries_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b performance_monitor_relon_pSeries
- . = 0x4f20
- altivec_unavailable_relon_pseries_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b altivec_unavailable_relon_pSeries
- . = 0x4f40
- vsx_unavailable_relon_pseries_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b vsx_unavailable_relon_pSeries
- . = 0x4f60
- facility_unavailable_relon_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b facility_unavailable_relon_pSeries
- . = 0x4f80
- hv_facility_unavailable_relon_trampoline:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b hv_facility_unavailable_relon_hv
- STD_RELON_EXCEPTION_PSERIES(0x5300, 0x1300, instruction_breakpoint)
- #ifdef CONFIG_PPC_DENORMALISATION
- . = 0x5500
- b denorm_exception_hv
- #endif
- STD_RELON_EXCEPTION_PSERIES(0x5700, 0x1700, altivec_assist)
- /* Other future vectors */
- .align 7
- .globl __end_interrupts
- __end_interrupts:
- .align 7
- system_call_entry:
- b system_call_common
- ppc64_runlatch_on_trampoline:
- b __ppc64_runlatch_on
- /*
- * Here r13 points to the paca, r9 contains the saved CR,
- * SRR0 and SRR1 are saved in r11 and r12,
- * r9 - r13 are saved in paca->exgen.
- */
- .align 7
- .globl data_access_common
- data_access_common:
- mfspr r10,SPRN_DAR
- std r10,PACA_EXGEN+EX_DAR(r13)
- mfspr r10,SPRN_DSISR
- stw r10,PACA_EXGEN+EX_DSISR(r13)
- EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
- RECONCILE_IRQ_STATE(r10, r11)
- ld r12,_MSR(r1)
- ld r3,PACA_EXGEN+EX_DAR(r13)
- lwz r4,PACA_EXGEN+EX_DSISR(r13)
- li r5,0x300
- b do_hash_page /* Try to handle as hpte fault */
- .align 7
- .globl h_data_storage_common
- h_data_storage_common:
- mfspr r10,SPRN_HDAR
- std r10,PACA_EXGEN+EX_DAR(r13)
- mfspr r10,SPRN_HDSISR
- stw r10,PACA_EXGEN+EX_DSISR(r13)
- EXCEPTION_PROLOG_COMMON(0xe00, PACA_EXGEN)
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl unknown_exception
- b ret_from_except
- .align 7
- .globl instruction_access_common
- instruction_access_common:
- EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
- RECONCILE_IRQ_STATE(r10, r11)
- ld r12,_MSR(r1)
- ld r3,_NIP(r1)
- andis. r4,r12,0x5820
- li r5,0x400
- b do_hash_page /* Try to handle as hpte fault */
- STD_EXCEPTION_COMMON(0xe20, h_instr_storage, unknown_exception)
- /*
- * Here is the common SLB miss user that is used when going to virtual
- * mode for SLB misses, that is currently not used
- */
- #ifdef __DISABLED__
- .align 7
- .globl slb_miss_user_common
- slb_miss_user_common:
- mflr r10
- std r3,PACA_EXGEN+EX_DAR(r13)
- stw r9,PACA_EXGEN+EX_CCR(r13)
- std r10,PACA_EXGEN+EX_LR(r13)
- std r11,PACA_EXGEN+EX_SRR0(r13)
- bl slb_allocate_user
- ld r10,PACA_EXGEN+EX_LR(r13)
- ld r3,PACA_EXGEN+EX_R3(r13)
- lwz r9,PACA_EXGEN+EX_CCR(r13)
- ld r11,PACA_EXGEN+EX_SRR0(r13)
- mtlr r10
- beq- slb_miss_fault
- andi. r10,r12,MSR_RI /* check for unrecoverable exception */
- beq- unrecov_user_slb
- mfmsr r10
- .machine push
- .machine "power4"
- mtcrf 0x80,r9
- .machine pop
- clrrdi r10,r10,2 /* clear RI before setting SRR0/1 */
- mtmsrd r10,1
- mtspr SRR0,r11
- mtspr SRR1,r12
- ld r9,PACA_EXGEN+EX_R9(r13)
- ld r10,PACA_EXGEN+EX_R10(r13)
- ld r11,PACA_EXGEN+EX_R11(r13)
- ld r12,PACA_EXGEN+EX_R12(r13)
- ld r13,PACA_EXGEN+EX_R13(r13)
- rfid
- b .
- slb_miss_fault:
- EXCEPTION_PROLOG_COMMON(0x380, PACA_EXGEN)
- ld r4,PACA_EXGEN+EX_DAR(r13)
- li r5,0
- std r4,_DAR(r1)
- std r5,_DSISR(r1)
- b handle_page_fault
- unrecov_user_slb:
- EXCEPTION_PROLOG_COMMON(0x4200, PACA_EXGEN)
- RECONCILE_IRQ_STATE(r10, r11)
- bl save_nvgprs
- 1: addi r3,r1,STACK_FRAME_OVERHEAD
- bl unrecoverable_exception
- b 1b
- #endif /* __DISABLED__ */
- /*
- * Machine check is different because we use a different
- * save area: PACA_EXMC instead of PACA_EXGEN.
- */
- .align 7
- .globl machine_check_common
- machine_check_common:
- mfspr r10,SPRN_DAR
- std r10,PACA_EXGEN+EX_DAR(r13)
- mfspr r10,SPRN_DSISR
- stw r10,PACA_EXGEN+EX_DSISR(r13)
- EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
- FINISH_NAP
- RECONCILE_IRQ_STATE(r10, r11)
- ld r3,PACA_EXGEN+EX_DAR(r13)
- lwz r4,PACA_EXGEN+EX_DSISR(r13)
- std r3,_DAR(r1)
- std r4,_DSISR(r1)
- bl save_nvgprs
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl machine_check_exception
- b ret_from_except
- .align 7
- .globl alignment_common
- alignment_common:
- mfspr r10,SPRN_DAR
- std r10,PACA_EXGEN+EX_DAR(r13)
- mfspr r10,SPRN_DSISR
- stw r10,PACA_EXGEN+EX_DSISR(r13)
- EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
- ld r3,PACA_EXGEN+EX_DAR(r13)
- lwz r4,PACA_EXGEN+EX_DSISR(r13)
- std r3,_DAR(r1)
- std r4,_DSISR(r1)
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl alignment_exception
- b ret_from_except
- .align 7
- .globl program_check_common
- program_check_common:
- EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl program_check_exception
- b ret_from_except
- .align 7
- .globl fp_unavailable_common
- fp_unavailable_common:
- EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
- bne 1f /* if from user, just load it up */
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl kernel_fp_unavailable_exception
- BUG_OPCODE
- 1:
- #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- BEGIN_FTR_SECTION
- /* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
- * transaction), go do TM stuff
- */
- rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
- bne- 2f
- END_FTR_SECTION_IFSET(CPU_FTR_TM)
- #endif
- bl load_up_fpu
- b fast_exception_return
- #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- 2: /* User process was in a transaction */
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl fp_unavailable_tm
- b ret_from_except
- #endif
- .align 7
- .globl altivec_unavailable_common
- altivec_unavailable_common:
- EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
- #ifdef CONFIG_ALTIVEC
- BEGIN_FTR_SECTION
- beq 1f
- #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- BEGIN_FTR_SECTION_NESTED(69)
- /* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
- * transaction), go do TM stuff
- */
- rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
- bne- 2f
- END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
- #endif
- bl load_up_altivec
- b fast_exception_return
- #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- 2: /* User process was in a transaction */
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl altivec_unavailable_tm
- b ret_from_except
- #endif
- 1:
- END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
- #endif
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl altivec_unavailable_exception
- b ret_from_except
- .align 7
- .globl vsx_unavailable_common
- vsx_unavailable_common:
- EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
- #ifdef CONFIG_VSX
- BEGIN_FTR_SECTION
- beq 1f
- #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- BEGIN_FTR_SECTION_NESTED(69)
- /* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
- * transaction), go do TM stuff
- */
- rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
- bne- 2f
- END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
- #endif
- b load_up_vsx
- #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- 2: /* User process was in a transaction */
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl vsx_unavailable_tm
- b ret_from_except
- #endif
- 1:
- END_FTR_SECTION_IFSET(CPU_FTR_VSX)
- #endif
- bl save_nvgprs
- RECONCILE_IRQ_STATE(r10, r11)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl vsx_unavailable_exception
- b ret_from_except
- STD_EXCEPTION_COMMON(0xf60, facility_unavailable, facility_unavailable_exception)
- STD_EXCEPTION_COMMON(0xf80, hv_facility_unavailable, facility_unavailable_exception)
- .align 7
- .globl __end_handlers
- __end_handlers:
- /* Equivalents to the above handlers for relocation-on interrupt vectors */
- STD_RELON_EXCEPTION_HV_OOL(0xe40, emulation_assist)
- MASKABLE_RELON_EXCEPTION_HV_OOL(0xe80, h_doorbell)
- STD_RELON_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
- STD_RELON_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
- STD_RELON_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
- STD_RELON_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
- STD_RELON_EXCEPTION_HV_OOL(0xf80, hv_facility_unavailable)
- #if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
- /*
- * Data area reserved for FWNMI option.
- * This address (0x7000) is fixed by the RPA.
- */
- .= 0x7000
- .globl fwnmi_data_area
- fwnmi_data_area:
- /* pseries and powernv need to keep the whole page from
- * 0x7000 to 0x8000 free for use by the firmware
- */
- . = 0x8000
- #endif /* defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV) */
- .globl hmi_exception_early
- hmi_exception_early:
- EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0xe60)
- mr r10,r1 /* Save r1 */
- ld r1,PACAEMERGSP(r13) /* Use emergency stack */
- subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
- std r9,_CCR(r1) /* save CR in stackframe */
- mfspr r11,SPRN_HSRR0 /* Save HSRR0 */
- std r11,_NIP(r1) /* save HSRR0 in stackframe */
- mfspr r12,SPRN_HSRR1 /* Save SRR1 */
- std r12,_MSR(r1) /* save SRR1 in stackframe */
- std r10,0(r1) /* make stack chain pointer */
- std r0,GPR0(r1) /* save r0 in stackframe */
- std r10,GPR1(r1) /* save r1 in stackframe */
- EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
- EXCEPTION_PROLOG_COMMON_3(0xe60)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl hmi_exception_realmode
- /* Windup the stack. */
- /* Move original HSRR0 and HSRR1 into the respective regs */
- ld r9,_MSR(r1)
- mtspr SPRN_HSRR1,r9
- ld r3,_NIP(r1)
- mtspr SPRN_HSRR0,r3
- ld r9,_CTR(r1)
- mtctr r9
- ld r9,_XER(r1)
- mtxer r9
- ld r9,_LINK(r1)
- mtlr r9
- REST_GPR(0, r1)
- REST_8GPRS(2, r1)
- REST_GPR(10, r1)
- ld r11,_CCR(r1)
- mtcr r11
- REST_GPR(11, r1)
- REST_2GPRS(12, r1)
- /* restore original r1. */
- ld r1,GPR1(r1)
- /*
- * Go to virtual mode and pull the HMI event information from
- * firmware.
- */
- .globl hmi_exception_after_realmode
- hmi_exception_after_realmode:
- SET_SCRATCH0(r13)
- EXCEPTION_PROLOG_0(PACA_EXGEN)
- b hmi_exception_hv
- #define MACHINE_CHECK_HANDLER_WINDUP \
- /* Clear MSR_RI before setting SRR0 and SRR1. */\
- li r0,MSR_RI; \
- mfmsr r9; /* get MSR value */ \
- andc r9,r9,r0; \
- mtmsrd r9,1; /* Clear MSR_RI */ \
- /* Move original SRR0 and SRR1 into the respective regs */ \
- ld r9,_MSR(r1); \
- mtspr SPRN_SRR1,r9; \
- ld r3,_NIP(r1); \
- mtspr SPRN_SRR0,r3; \
- ld r9,_CTR(r1); \
- mtctr r9; \
- ld r9,_XER(r1); \
- mtxer r9; \
- ld r9,_LINK(r1); \
- mtlr r9; \
- REST_GPR(0, r1); \
- REST_8GPRS(2, r1); \
- REST_GPR(10, r1); \
- ld r11,_CCR(r1); \
- mtcr r11; \
- /* Decrement paca->in_mce. */ \
- lhz r12,PACA_IN_MCE(r13); \
- subi r12,r12,1; \
- sth r12,PACA_IN_MCE(r13); \
- REST_GPR(11, r1); \
- REST_2GPRS(12, r1); \
- /* restore original r1. */ \
- ld r1,GPR1(r1)
- /*
- * Handle machine check early in real mode. We come here with
- * ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
- */
- .align 7
- .globl machine_check_handle_early
- machine_check_handle_early:
- std r0,GPR0(r1) /* Save r0 */
- EXCEPTION_PROLOG_COMMON_3(0x200)
- bl save_nvgprs
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl machine_check_early
- std r3,RESULT(r1) /* Save result */
- ld r12,_MSR(r1)
- #ifdef CONFIG_PPC_P7_NAP
- /*
- * Check if thread was in power saving mode. We come here when any
- * of the following is true:
- * a. thread wasn't in power saving mode
- * b. thread was in power saving mode with no state loss or
- * supervisor state loss
- *
- * Go back to nap again if (b) is true.
- */
- rlwinm. r11,r12,47-31,30,31 /* Was it in power saving mode? */
- beq 4f /* No, it wasn;t */
- /* Thread was in power saving mode. Go back to nap again. */
- cmpwi r11,2
- bne 3f
- /* Supervisor state loss */
- li r0,1
- stb r0,PACA_NAPSTATELOST(r13)
- 3: bl machine_check_queue_event
- MACHINE_CHECK_HANDLER_WINDUP
- GET_PACA(r13)
- ld r1,PACAR1(r13)
- li r3,PNV_THREAD_NAP
- b power7_enter_nap_mode
- 4:
- #endif
- /*
- * Check if we are coming from hypervisor userspace. If yes then we
- * continue in host kernel in V mode to deliver the MC event.
- */
- rldicl. r11,r12,4,63 /* See if MC hit while in HV mode. */
- beq 5f
- andi. r11,r12,MSR_PR /* See if coming from user. */
- bne 9f /* continue in V mode if we are. */
- 5:
- #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
- /*
- * We are coming from kernel context. Check if we are coming from
- * guest. if yes, then we can continue. We will fall through
- * do_kvm_200->kvmppc_interrupt to deliver the MC event to guest.
- */
- lbz r11,HSTATE_IN_GUEST(r13)
- cmpwi r11,0 /* Check if coming from guest */
- bne 9f /* continue if we are. */
- #endif
- /*
- * At this point we are not sure about what context we come from.
- * Queue up the MCE event and return from the interrupt.
- * But before that, check if this is an un-recoverable exception.
- * If yes, then stay on emergency stack and panic.
- */
- andi. r11,r12,MSR_RI
- bne 2f
- 1: mfspr r11,SPRN_SRR0
- ld r10,PACAKBASE(r13)
- LOAD_HANDLER(r10,unrecover_mce)
- mtspr SPRN_SRR0,r10
- ld r10,PACAKMSR(r13)
- /*
- * We are going down. But there are chances that we might get hit by
- * another MCE during panic path and we may run into unstable state
- * with no way out. Hence, turn ME bit off while going down, so that
- * when another MCE is hit during panic path, system will checkstop
- * and hypervisor will get restarted cleanly by SP.
- */
- li r3,MSR_ME
- andc r10,r10,r3 /* Turn off MSR_ME */
- mtspr SPRN_SRR1,r10
- rfid
- b .
- 2:
- /*
- * Check if we have successfully handled/recovered from error, if not
- * then stay on emergency stack and panic.
- */
- ld r3,RESULT(r1) /* Load result */
- cmpdi r3,0 /* see if we handled MCE successfully */
- beq 1b /* if !handled then panic */
- /*
- * Return from MC interrupt.
- * Queue up the MCE event so that we can log it later, while
- * returning from kernel or opal call.
- */
- bl machine_check_queue_event
- MACHINE_CHECK_HANDLER_WINDUP
- rfid
- 9:
- /* Deliver the machine check to host kernel in V mode. */
- MACHINE_CHECK_HANDLER_WINDUP
- b machine_check_pSeries
- unrecover_mce:
- /* Invoke machine_check_exception to print MCE event and panic. */
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl machine_check_exception
- /*
- * We will not reach here. Even if we did, there is no way out. Call
- * unrecoverable_exception and die.
- */
- 1: addi r3,r1,STACK_FRAME_OVERHEAD
- bl unrecoverable_exception
- b 1b
- /*
- * r13 points to the PACA, r9 contains the saved CR,
- * r12 contain the saved SRR1, SRR0 is still ready for return
- * r3 has the faulting address
- * r9 - r13 are saved in paca->exslb.
- * r3 is saved in paca->slb_r3
- * We assume we aren't going to take any exceptions during this procedure.
- */
- slb_miss_realmode:
- mflr r10
- #ifdef CONFIG_RELOCATABLE
- mtctr r11
- #endif
- stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
- std r10,PACA_EXSLB+EX_LR(r13) /* save LR */
- bl slb_allocate_realmode
- /* All done -- return from exception. */
- ld r10,PACA_EXSLB+EX_LR(r13)
- ld r3,PACA_EXSLB+EX_R3(r13)
- lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */
- mtlr r10
- andi. r10,r12,MSR_RI /* check for unrecoverable exception */
- beq- 2f
- .machine push
- .machine "power4"
- mtcrf 0x80,r9
- mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */
- .machine pop
- RESTORE_PPR_PACA(PACA_EXSLB, r9)
- ld r9,PACA_EXSLB+EX_R9(r13)
- ld r10,PACA_EXSLB+EX_R10(r13)
- ld r11,PACA_EXSLB+EX_R11(r13)
- ld r12,PACA_EXSLB+EX_R12(r13)
- ld r13,PACA_EXSLB+EX_R13(r13)
- rfid
- b . /* prevent speculative execution */
- 2: mfspr r11,SPRN_SRR0
- ld r10,PACAKBASE(r13)
- LOAD_HANDLER(r10,unrecov_slb)
- mtspr SPRN_SRR0,r10
- ld r10,PACAKMSR(r13)
- mtspr SPRN_SRR1,r10
- rfid
- b .
- unrecov_slb:
- EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
- RECONCILE_IRQ_STATE(r10, r11)
- bl save_nvgprs
- 1: addi r3,r1,STACK_FRAME_OVERHEAD
- bl unrecoverable_exception
- b 1b
- #ifdef CONFIG_PPC_970_NAP
- power4_fixup_nap:
- andc r9,r9,r10
- std r9,TI_LOCAL_FLAGS(r11)
- ld r10,_LINK(r1) /* make idle task do the */
- std r10,_NIP(r1) /* equivalent of a blr */
- blr
- #endif
- /*
- * Hash table stuff
- */
- .align 7
- do_hash_page:
- std r3,_DAR(r1)
- std r4,_DSISR(r1)
- andis. r0,r4,0xa410 /* weird error? */
- bne- handle_page_fault /* if not, try to insert a HPTE */
- andis. r0,r4,DSISR_DABRMATCH@h
- bne- handle_dabr_fault
- CURRENT_THREAD_INFO(r11, r1)
- lwz r0,TI_PREEMPT(r11) /* If we're in an "NMI" */
- andis. r0,r0,NMI_MASK@h /* (i.e. an irq when soft-disabled) */
- bne 77f /* then don't call hash_page now */
- /*
- * We need to set the _PAGE_USER bit if MSR_PR is set or if we are
- * accessing a userspace segment (even from the kernel). We assume
- * kernel addresses always have the high bit set.
- */
- rlwinm r4,r4,32-25+9,31-9,31-9 /* DSISR_STORE -> _PAGE_RW */
- rotldi r0,r3,15 /* Move high bit into MSR_PR posn */
- orc r0,r12,r0 /* MSR_PR | ~high_bit */
- rlwimi r4,r0,32-13,30,30 /* becomes _PAGE_USER access bit */
- ori r4,r4,1 /* add _PAGE_PRESENT */
- rlwimi r4,r5,22+2,31-2,31-2 /* Set _PAGE_EXEC if trap is 0x400 */
- /*
- * r3 contains the faulting address
- * r4 contains the required access permissions
- * r5 contains the trap number
- * r6 contains dsisr
- *
- * at return r3 = 0 for success, 1 for page fault, negative for error
- */
- ld r6,_DSISR(r1)
- bl hash_page /* build HPTE if possible */
- cmpdi r3,0 /* see if hash_page succeeded */
- /* Success */
- beq fast_exc_return_irq /* Return from exception on success */
- /* Error */
- blt- 13f
- /* Here we have a page fault that hash_page can't handle. */
- handle_page_fault:
- 11: ld r4,_DAR(r1)
- ld r5,_DSISR(r1)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_page_fault
- cmpdi r3,0
- beq+ 12f
- bl save_nvgprs
- mr r5,r3
- addi r3,r1,STACK_FRAME_OVERHEAD
- lwz r4,_DAR(r1)
- bl bad_page_fault
- b ret_from_except
- /* We have a data breakpoint exception - handle it */
- handle_dabr_fault:
- bl save_nvgprs
- ld r4,_DAR(r1)
- ld r5,_DSISR(r1)
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_break
- 12: b ret_from_except_lite
- /* We have a page fault that hash_page could handle but HV refused
- * the PTE insertion
- */
- 13: bl save_nvgprs
- mr r5,r3
- addi r3,r1,STACK_FRAME_OVERHEAD
- ld r4,_DAR(r1)
- bl low_hash_fault
- b ret_from_except
- /*
- * We come here as a result of a DSI at a point where we don't want
- * to call hash_page, such as when we are accessing memory (possibly
- * user memory) inside a PMU interrupt that occurred while interrupts
- * were soft-disabled. We want to invoke the exception handler for
- * the access, or panic if there isn't a handler.
- */
- 77: bl save_nvgprs
- mr r4,r3
- addi r3,r1,STACK_FRAME_OVERHEAD
- li r5,SIGSEGV
- bl bad_page_fault
- b ret_from_except
- /*
- * Here we have detected that the kernel stack pointer is bad.
- * R9 contains the saved CR, r13 points to the paca,
- * r10 contains the (bad) kernel stack pointer,
- * r11 and r12 contain the saved SRR0 and SRR1.
- * We switch to using an emergency stack, save the registers there,
- * and call kernel_bad_stack(), which panics.
- */
- bad_stack:
- ld r1,PACAEMERGSP(r13)
- subi r1,r1,64+INT_FRAME_SIZE
- std r9,_CCR(r1)
- std r10,GPR1(r1)
- std r11,_NIP(r1)
- std r12,_MSR(r1)
- mfspr r11,SPRN_DAR
- mfspr r12,SPRN_DSISR
- std r11,_DAR(r1)
- std r12,_DSISR(r1)
- mflr r10
- mfctr r11
- mfxer r12
- std r10,_LINK(r1)
- std r11,_CTR(r1)
- std r12,_XER(r1)
- SAVE_GPR(0,r1)
- SAVE_GPR(2,r1)
- ld r10,EX_R3(r3)
- std r10,GPR3(r1)
- SAVE_GPR(4,r1)
- SAVE_4GPRS(5,r1)
- ld r9,EX_R9(r3)
- ld r10,EX_R10(r3)
- SAVE_2GPRS(9,r1)
- ld r9,EX_R11(r3)
- ld r10,EX_R12(r3)
- ld r11,EX_R13(r3)
- std r9,GPR11(r1)
- std r10,GPR12(r1)
- std r11,GPR13(r1)
- BEGIN_FTR_SECTION
- ld r10,EX_CFAR(r3)
- std r10,ORIG_GPR3(r1)
- END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
- SAVE_8GPRS(14,r1)
- SAVE_10GPRS(22,r1)
- lhz r12,PACA_TRAP_SAVE(r13)
- std r12,_TRAP(r1)
- addi r11,r1,INT_FRAME_SIZE
- std r11,0(r1)
- li r12,0
- std r12,0(r11)
- ld r2,PACATOC(r13)
- ld r11,exception_marker@toc(r2)
- std r12,RESULT(r1)
- std r11,STACK_FRAME_OVERHEAD-16(r1)
- 1: addi r3,r1,STACK_FRAME_OVERHEAD
- bl kernel_bad_stack
- b 1b
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