[linux-2.6-block.git] / arch / powerpc / kernel / exceptions-64s.S

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * 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>
#include <asm/head-64.h>
#include <asm/feature-fixups.h>
#include <asm/kup.h>

/*
 * There are a few constraints to be concerned with.
 * - Real mode exceptions code/data must be located at their physical location.
 * - Virtual mode exceptions must be mapped at their 0xc000... location.
 * - Fixed location code must not call directly beyond the __end_interrupts
 *   area when built with CONFIG_RELOCATABLE. LOAD_HANDLER / bctr sequence
 *   must be used.
 * - LOAD_HANDLER targets must be within first 64K of physical 0 /
 *   virtual 0xc00...
 * - Conditional branch targets must be within +/-32K of caller.
 *
 * "Virtual exceptions" run with relocation on (MSR_IR=1, MSR_DR=1), and
 * therefore don't have to run in physically located code or rfid to
 * virtual mode kernel code. However on relocatable kernels they do have
 * to branch to KERNELBASE offset because the rest of the kernel (outside
 * the exception vectors) may be located elsewhere.
 *
 * Virtual exceptions correspond with physical, except their entry points
 * are offset by 0xc000000000000000 and also tend to get an added 0x4000
 * offset applied. Virtual exceptions are enabled with the Alternate
 * Interrupt Location (AIL) bit set in the LPCR. However this does not
 * guarantee they will be delivered virtually. Some conditions (see the ISA)
 * cause exceptions to be delivered in real mode.
 *
 * It's impossible to receive interrupts below 0x300 via AIL.
 *
 * KVM: None of the virtual exceptions are from the guest. Anything that
 * escalated to HV=1 from HV=0 is delivered via real mode handlers.
 *
 *
 * We layout physical memory as follows:
 * 0x0000 - 0x00ff : Secondary processor spin code
 * 0x0100 - 0x18ff : Real mode pSeries interrupt vectors
 * 0x1900 - 0x3fff : Real mode trampolines
 * 0x4000 - 0x58ff : Relon (IR=1,DR=1) mode pSeries interrupt vectors
 * 0x5900 - 0x6fff : Relon mode trampolines
 * 0x7000 - 0x7fff : FWNMI data area
 * 0x8000 -   .... : Common interrupt handlers, remaining early
 *                   setup code, rest of kernel.
 *
 * We could reclaim 0x4000-0x42ff for real mode trampolines if the space
 * is necessary. Until then it's more consistent to explicitly put VIRT_NONE
 * vectors there.
 */
OPEN_FIXED_SECTION(real_vectors,        0x0100, 0x1900)
OPEN_FIXED_SECTION(real_trampolines,    0x1900, 0x4000)
OPEN_FIXED_SECTION(virt_vectors,        0x4000, 0x5900)
OPEN_FIXED_SECTION(virt_trampolines,    0x5900, 0x7000)

#ifdef CONFIG_PPC_POWERNV
        .globl start_real_trampolines
        .globl end_real_trampolines
        .globl start_virt_trampolines
        .globl end_virt_trampolines
#endif

#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
/*
 * Data area reserved for FWNMI option.
 * This address (0x7000) is fixed by the RPA.
 * pseries and powernv need to keep the whole page from
 * 0x7000 to 0x8000 free for use by the firmware
 */
ZERO_FIXED_SECTION(fwnmi_page,          0x7000, 0x8000)
OPEN_TEXT_SECTION(0x8000)
#else
OPEN_TEXT_SECTION(0x7000)
#endif

USE_FIXED_SECTION(real_vectors)

/*
 * 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.
 */
        .globl __start_interrupts
__start_interrupts:

/* No virt vectors corresponding with 0x0..0x100 */
EXC_VIRT_NONE(0x4000, 0x100)


EXC_REAL_BEGIN(system_reset, 0x100, 0x100)
        SET_SCRATCH0(r13)
        EXCEPTION_PROLOG_0 PACA_EXNMI

        /* This is EXCEPTION_PROLOG_1 with the idle feature section added */
        OPT_SAVE_REG_TO_PACA(PACA_EXNMI+EX_PPR, r9, CPU_FTR_HAS_PPR)
        OPT_SAVE_REG_TO_PACA(PACA_EXNMI+EX_CFAR, r10, CPU_FTR_CFAR)
        INTERRUPT_TO_KERNEL
        SAVE_CTR(r10, PACA_EXNMI)
        mfcr    r9

#ifdef CONFIG_PPC_P7_NAP
        /*
         * If running native on arch 2.06 or later, check if we are waking up
         * from nap/sleep/winkle, and branch to idle handler. This tests SRR1
         * bits 46:47. A non-0 value indicates that we are coming from a power
         * saving state. The idle wakeup handler initially runs in real mode,
         * but we branch to the 0xc000... address so we can turn on relocation
         * with mtmsr.
         */
        BEGIN_FTR_SECTION
        mfspr   r10,SPRN_SRR1
        rlwinm. r10,r10,47-31,30,31
        beq-    1f
        cmpwi   cr1,r10,2
        mfspr   r3,SPRN_SRR1
        bltlr   cr1     /* no state loss, return to idle caller */
        BRANCH_TO_C000(r10, system_reset_idle_common)
1:
        END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#endif

        KVMTEST EXC_STD 0x100
        std     r11,PACA_EXNMI+EX_R11(r13)
        std     r12,PACA_EXNMI+EX_R12(r13)
        GET_SCRATCH0(r10)
        std     r10,PACA_EXNMI+EX_R13(r13)

        EXCEPTION_PROLOG_2_REAL system_reset_common, EXC_STD, 0
        /*
         * MSR_RI is not enabled, because PACA_EXNMI and nmi stack is
         * being used, so a nested NMI exception would corrupt it.
         */

EXC_REAL_END(system_reset, 0x100, 0x100)
EXC_VIRT_NONE(0x4100, 0x100)
TRAMP_KVM(PACA_EXNMI, 0x100)

#ifdef CONFIG_PPC_P7_NAP
EXC_COMMON_BEGIN(system_reset_idle_common)
        /*
         * This must be a direct branch (without linker branch stub) because
         * we can not use TOC at this point as r2 may not be restored yet.
         */
        b       idle_return_gpr_loss
#endif

EXC_COMMON_BEGIN(system_reset_common)
        /*
         * Increment paca->in_nmi then enable MSR_RI. SLB or MCE will be able
         * to recover, but nested NMI will notice in_nmi and not recover
         * because of the use of the NMI stack. in_nmi reentrancy is tested in
         * system_reset_exception.
         */
        lhz     r10,PACA_IN_NMI(r13)
        addi    r10,r10,1
        sth     r10,PACA_IN_NMI(r13)
        li      r10,MSR_RI
        mtmsrd  r10,1

        mr      r10,r1
        ld      r1,PACA_NMI_EMERG_SP(r13)
        subi    r1,r1,INT_FRAME_SIZE
        EXCEPTION_COMMON_STACK(PACA_EXNMI, 0x100)
        bl      save_nvgprs
        /*
         * Set IRQS_ALL_DISABLED unconditionally so arch_irqs_disabled does
         * the right thing. We do not want to reconcile because that goes
         * through irq tracing which we don't want in NMI.
         *
         * Save PACAIRQHAPPENED because some code will do a hard disable
         * (e.g., xmon). So we want to restore this back to where it was
         * when we return. DAR is unused in the stack, so save it there.
         */
        li      r10,IRQS_ALL_DISABLED
        stb     r10,PACAIRQSOFTMASK(r13)
        lbz     r10,PACAIRQHAPPENED(r13)
        std     r10,_DAR(r1)

        addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      system_reset_exception

        /* This (and MCE) can be simplified with mtmsrd L=1 */
        /* Clear MSR_RI before setting SRR0 and SRR1. */
        li      r0,MSR_RI
        mfmsr   r9
        andc    r9,r9,r0
        mtmsrd  r9,1

        /*
         * MSR_RI is clear, now we can decrement paca->in_nmi.
         */
        lhz     r10,PACA_IN_NMI(r13)
        subi    r10,r10,1
        sth     r10,PACA_IN_NMI(r13)

        /*
         * Restore soft mask settings.
         */
        ld      r10,_DAR(r1)
        stb     r10,PACAIRQHAPPENED(r13)
        ld      r10,SOFTE(r1)
        stb     r10,PACAIRQSOFTMASK(r13)

        /*
         * Keep below code in synch with MACHINE_CHECK_HANDLER_WINDUP.
         * Should share common bits...
         */

        /* 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
        REST_GPR(11, r1)
        REST_2GPRS(12, r1)
        /* restore original r1. */
        ld      r1,GPR1(r1)
        RFI_TO_USER_OR_KERNEL

#ifdef CONFIG_PPC_PSERIES
/*
 * Vectors for the FWNMI option.  Share common code.
 */
TRAMP_REAL_BEGIN(system_reset_fwnmi)
        SET_SCRATCH0(r13)               /* save r13 */
        /* See comment at system_reset exception */
        EXCEPTION_PROLOG_NORI(PACA_EXNMI, system_reset_common, EXC_STD,
                              0, 0x100)
#endif /* CONFIG_PPC_PSERIES */


EXC_REAL_BEGIN(machine_check, 0x200, 0x100)
        /* 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
         */
        SET_SCRATCH0(r13)               /* save r13 */
        EXCEPTION_PROLOG_0 PACA_EXMC
BEGIN_FTR_SECTION
        b       machine_check_common_early
FTR_SECTION_ELSE
        b       machine_check_pSeries_0
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
EXC_REAL_END(machine_check, 0x200, 0x100)
EXC_VIRT_NONE(0x4200, 0x100)
TRAMP_REAL_BEGIN(machine_check_common_early)
        EXCEPTION_PROLOG_1 EXC_STD, PACA_EXMC, 0, 0x200, 0
        /*
         * 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.
         *
         * This interrupt can wake directly from idle. If that is the case,
         * the machine check is handled then the idle wakeup code is called
         * to restore state.
         */
        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,MAX_MCE_DEPTH
        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 */
        /* We don't touch AMR here, we never go to virtual mode */
        /* Save r9 through r13 from EXMC save area to stack frame. */
        EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
        mfmsr   r11                     /* get MSR value */
BEGIN_FTR_SECTION
        ori     r11,r11,MSR_ME          /* turn on ME bit */
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
        ori     r11,r11,MSR_RI          /* turn on RI bit */
        LOAD_HANDLER(r12, machine_check_handle_early)
1:      mtspr   SPRN_SRR0,r12
        mtspr   SPRN_SRR1,r11
        RFI_TO_KERNEL
        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)
        LOAD_HANDLER(r12, unrecover_mce)
        li      r10,MSR_ME
        andc    r11,r11,r10             /* Turn off MSR_ME */
        b       1b
        b       .       /* prevent speculative execution */

TRAMP_REAL_BEGIN(machine_check_pSeries)
        .globl machine_check_fwnmi
machine_check_fwnmi:
        SET_SCRATCH0(r13)               /* save r13 */
        EXCEPTION_PROLOG_0 PACA_EXMC
BEGIN_FTR_SECTION
        b       machine_check_common_early
END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
machine_check_pSeries_0:
        EXCEPTION_PROLOG_1 EXC_STD, PACA_EXMC, 1, 0x200, 0
        /*
         * MSR_RI is not enabled, because PACA_EXMC is being used, so a
         * nested machine check corrupts it. machine_check_common enables
         * MSR_RI.
         */
        EXCEPTION_PROLOG_2_REAL machine_check_common, EXC_STD, 0

TRAMP_KVM_SKIP(PACA_EXMC, 0x200)

EXC_COMMON_BEGIN(machine_check_common)
        /*
         * Machine check is different because we use a different
         * save area: PACA_EXMC instead of PACA_EXGEN.
         */
        mfspr   r10,SPRN_DAR
        std     r10,PACA_EXMC+EX_DAR(r13)
        mfspr   r10,SPRN_DSISR
        stw     r10,PACA_EXMC+EX_DSISR(r13)
        EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
        FINISH_NAP
        RECONCILE_IRQ_STATE(r10, r11)
        ld      r3,PACA_EXMC+EX_DAR(r13)
        lwz     r4,PACA_EXMC+EX_DSISR(r13)
        /* Enable MSR_RI when finished with PACA_EXMC */
        li      r10,MSR_RI
        mtmsrd  r10,1
        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

#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)

#ifdef CONFIG_PPC_P7_NAP
/*
 * This is an idle wakeup. Low level machine check has already been
 * done. Queue the event then call the idle code to do the wake up.
 */
EXC_COMMON_BEGIN(machine_check_idle_common)
        bl      machine_check_queue_event

        /*
         * We have not used any non-volatile GPRs here, and as a rule
         * most exception code including machine check does not.
         * Therefore PACA_NAPSTATELOST does not need to be set. Idle
         * wakeup will restore volatile registers.
         *
         * Load the original SRR1 into r3 for pnv_powersave_wakeup_mce.
         *
         * Then decrement MCE nesting after finishing with the stack.
         */
        ld      r3,_MSR(r1)
        ld      r4,_LINK(r1)

        lhz     r11,PACA_IN_MCE(r13)
        subi    r11,r11,1
        sth     r11,PACA_IN_MCE(r13)

        mtlr    r4
        rlwinm  r10,r3,47-31,30,31
        cmpwi   cr1,r10,2
        bltlr   cr1     /* no state loss, return to idle caller */
        b       idle_return_gpr_loss
#endif
        /*
         * 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.
         */
EXC_COMMON_BEGIN(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)
BEGIN_FTR_SECTION
        b       4f
END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)

#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,
         *    supervisor state loss or hypervisor state loss.
         *
         * Go back to nap/sleep/winkle mode again if (b) is true.
         */
        BEGIN_FTR_SECTION
        rlwinm. r11,r12,47-31,30,31
        bne     machine_check_idle_common
        END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#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
4:      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
BEGIN_FTR_SECTION
        /*
         * 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. */
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
#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
        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
        RFI_TO_KERNEL
        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 */
BEGIN_FTR_SECTION
        /*
         * 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
        RFI_TO_USER_OR_KERNEL
FTR_SECTION_ELSE
        /*
         * pSeries: Return from MC interrupt. Before that stay on emergency
         * stack and call machine_check_exception to log the MCE event.
         */
        LOAD_HANDLER(r10,mce_return)
        mtspr   SPRN_SRR0,r10
        ld      r10,PACAKMSR(r13)
        mtspr   SPRN_SRR1,r10
        RFI_TO_KERNEL
        b       .
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
9:
        /* Deliver the machine check to host kernel in V mode. */
        MACHINE_CHECK_HANDLER_WINDUP
        SET_SCRATCH0(r13)               /* save r13 */
        EXCEPTION_PROLOG_0 PACA_EXMC
        b       machine_check_pSeries_0

EXC_COMMON_BEGIN(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

EXC_COMMON_BEGIN(mce_return)
        /* Invoke machine_check_exception to print MCE event and return. */
        addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      machine_check_exception
        MACHINE_CHECK_HANDLER_WINDUP
        RFI_TO_KERNEL
        b       .

EXC_REAL_BEGIN(data_access, 0x300, 0x80)
SET_SCRATCH0(r13)               /* save r13 */
EXCEPTION_PROLOG_0 PACA_EXGEN
        b       tramp_real_data_access
EXC_REAL_END(data_access, 0x300, 0x80)

TRAMP_REAL_BEGIN(tramp_real_data_access)
EXCEPTION_PROLOG_1 EXC_STD, PACA_EXGEN, 1, 0x300, 0
        /*
         * DAR/DSISR must be read before setting MSR[RI], because
         * a d-side MCE will clobber those registers so is not
         * recoverable if they are live.
         */
        mfspr   r10,SPRN_DAR
        mfspr   r11,SPRN_DSISR
        std     r10,PACA_EXGEN+EX_DAR(r13)
        stw     r11,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_2_REAL data_access_common, EXC_STD, 1

EXC_VIRT_BEGIN(data_access, 0x4300, 0x80)
SET_SCRATCH0(r13)               /* save r13 */
EXCEPTION_PROLOG_0 PACA_EXGEN
EXCEPTION_PROLOG_1 EXC_STD, PACA_EXGEN, 0, 0x300, 0
        mfspr   r10,SPRN_DAR
        mfspr   r11,SPRN_DSISR
        std     r10,PACA_EXGEN+EX_DAR(r13)
        stw     r11,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_2_VIRT data_access_common, EXC_STD
EXC_VIRT_END(data_access, 0x4300, 0x80)

TRAMP_KVM_SKIP(PACA_EXGEN, 0x300)

EXC_COMMON_BEGIN(data_access_common)
        /*
         * 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.
         * EX_DAR and EX_DSISR have saved DAR/DSISR
         */
        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
        std     r3,_DAR(r1)
        std     r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
        b       do_hash_page            /* Try to handle as hpte fault */
MMU_FTR_SECTION_ELSE
        b       handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)


EXC_REAL_BEGIN(data_access_slb, 0x380, 0x80)
SET_SCRATCH0(r13)               /* save r13 */
EXCEPTION_PROLOG_0 PACA_EXSLB
        b       tramp_real_data_access_slb
EXC_REAL_END(data_access_slb, 0x380, 0x80)

TRAMP_REAL_BEGIN(tramp_real_data_access_slb)
EXCEPTION_PROLOG_1 EXC_STD, PACA_EXSLB, 1, 0x380, 0
        mfspr   r10,SPRN_DAR
        std     r10,PACA_EXSLB+EX_DAR(r13)
EXCEPTION_PROLOG_2_REAL data_access_slb_common, EXC_STD, 1

EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
SET_SCRATCH0(r13)               /* save r13 */
EXCEPTION_PROLOG_0 PACA_EXSLB
EXCEPTION_PROLOG_1 EXC_STD, PACA_EXSLB, 0, 0x380, 0
        mfspr   r10,SPRN_DAR
        std     r10,PACA_EXSLB+EX_DAR(r13)
EXCEPTION_PROLOG_2_VIRT data_access_slb_common, EXC_STD
EXC_VIRT_END(data_access_slb, 0x4380, 0x80)

TRAMP_KVM_SKIP(PACA_EXSLB, 0x380)

EXC_COMMON_BEGIN(data_access_slb_common)
        EXCEPTION_PROLOG_COMMON(0x380, PACA_EXSLB)
        ld      r4,PACA_EXSLB+EX_DAR(r13)
        std     r4,_DAR(r1)
        addi    r3,r1,STACK_FRAME_OVERHEAD
BEGIN_MMU_FTR_SECTION
        /* HPT case, do SLB fault */
        bl      do_slb_fault
        cmpdi   r3,0
        bne-    1f
        b       fast_exception_return
1:      /* Error case */
MMU_FTR_SECTION_ELSE
        /* Radix case, access is outside page table range */
        li      r3,-EFAULT
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
        std     r3,RESULT(r1)
        bl      save_nvgprs
        RECONCILE_IRQ_STATE(r10, r11)
        ld      r4,_DAR(r1)
        ld      r5,RESULT(r1)
        addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      do_bad_slb_fault
        b       ret_from_except


EXC_REAL(instruction_access, 0x400, 0x80)
EXC_VIRT(instruction_access, 0x4400, 0x80, 0x400)
TRAMP_KVM(PACA_EXGEN, 0x400)

EXC_COMMON_BEGIN(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,DSISR_SRR1_MATCH_64S@h
        li      r5,0x400
        std     r3,_DAR(r1)
        std     r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
        b       do_hash_page            /* Try to handle as hpte fault */
MMU_FTR_SECTION_ELSE
        b       handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)


EXC_REAL_BEGIN(instruction_access_slb, 0x480, 0x80)
EXCEPTION_PROLOG(PACA_EXSLB, instruction_access_slb_common, EXC_STD, 1, 0x480);
EXC_REAL_END(instruction_access_slb, 0x480, 0x80)

EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
EXCEPTION_RELON_PROLOG(PACA_EXSLB, instruction_access_slb_common, EXC_STD, 0, 0x480);
EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)

TRAMP_KVM(PACA_EXSLB, 0x480)

EXC_COMMON_BEGIN(instruction_access_slb_common)
        EXCEPTION_PROLOG_COMMON(0x480, PACA_EXSLB)
        ld      r4,_NIP(r1)
        addi    r3,r1,STACK_FRAME_OVERHEAD
BEGIN_MMU_FTR_SECTION
        /* HPT case, do SLB fault */
        bl      do_slb_fault
        cmpdi   r3,0
        bne-    1f
        b       fast_exception_return
1:      /* Error case */
MMU_FTR_SECTION_ELSE
        /* Radix case, access is outside page table range */
        li      r3,-EFAULT
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
        std     r3,RESULT(r1)
        bl      save_nvgprs
        RECONCILE_IRQ_STATE(r10, r11)
        ld      r4,_NIP(r1)
        ld      r5,RESULT(r1)
        addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      do_bad_slb_fault
        b       ret_from_except


EXC_REAL_BEGIN(hardware_interrupt, 0x500, 0x100)
        .globl hardware_interrupt_hv;
hardware_interrupt_hv:
        BEGIN_FTR_SECTION
                MASKABLE_EXCEPTION_HV(0x500, hardware_interrupt_common, IRQS_DISABLED)
        FTR_SECTION_ELSE
                MASKABLE_EXCEPTION(0x500, hardware_interrupt_common, IRQS_DISABLED)
        ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
EXC_REAL_END(hardware_interrupt, 0x500, 0x100)

EXC_VIRT_BEGIN(hardware_interrupt, 0x4500, 0x100)
        .globl hardware_interrupt_relon_hv;
hardware_interrupt_relon_hv:
        BEGIN_FTR_SECTION
                MASKABLE_RELON_EXCEPTION_HV(0x500, hardware_interrupt_common,
                                            IRQS_DISABLED)
        FTR_SECTION_ELSE
                __MASKABLE_RELON_EXCEPTION(0x500, hardware_interrupt_common,
                                           EXC_STD, 1, IRQS_DISABLED)
        ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
EXC_VIRT_END(hardware_interrupt, 0x4500, 0x100)

TRAMP_KVM(PACA_EXGEN, 0x500)
TRAMP_KVM_HV(PACA_EXGEN, 0x500)
EXC_COMMON_ASYNC(hardware_interrupt_common, 0x500, do_IRQ)


EXC_REAL_BEGIN(alignment, 0x600, 0x100)
SET_SCRATCH0(r13)               /* save r13 */
EXCEPTION_PROLOG_0 PACA_EXGEN
EXCEPTION_PROLOG_1 EXC_STD, PACA_EXGEN, 1, 0x600, 0
        mfspr   r10,SPRN_DAR
        mfspr   r11,SPRN_DSISR
        std     r10,PACA_EXGEN+EX_DAR(r13)
        stw     r11,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_2_REAL alignment_common, EXC_STD, 1
EXC_REAL_END(alignment, 0x600, 0x100)

EXC_VIRT_BEGIN(alignment, 0x4600, 0x100)
SET_SCRATCH0(r13)               /* save r13 */
EXCEPTION_PROLOG_0 PACA_EXGEN
EXCEPTION_PROLOG_1 EXC_STD, PACA_EXGEN, 0, 0x600, 0
        mfspr   r10,SPRN_DAR
        mfspr   r11,SPRN_DSISR
        std     r10,PACA_EXGEN+EX_DAR(r13)
        stw     r11,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_2_VIRT alignment_common, EXC_STD
EXC_VIRT_END(alignment, 0x4600, 0x100)

TRAMP_KVM(PACA_EXGEN, 0x600)
EXC_COMMON_BEGIN(alignment_common)
        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


EXC_REAL(program_check, 0x700, 0x100)
EXC_VIRT(program_check, 0x4700, 0x100, 0x700)
TRAMP_KVM(PACA_EXGEN, 0x700)
EXC_COMMON_BEGIN(program_check_common)
        /*
         * It's possible to receive a TM Bad Thing type program check with
         * userspace register values (in particular r1), but with SRR1 reporting
         * that we came from the kernel. Normally that would confuse the bad
         * stack logic, and we would report a bad kernel stack pointer. Instead
         * we switch to the emergency stack if we're taking a TM Bad Thing from
         * the kernel.
         */
        li      r10,MSR_PR              /* Build a mask of MSR_PR ..    */
        oris    r10,r10,0x200000@h      /* .. and SRR1_PROGTM           */
        and     r10,r10,r12             /* Mask SRR1 with that.         */
        srdi    r10,r10,8               /* Shift it so we can compare   */
        cmpldi  r10,(0x200000 >> 8)     /* .. with an immediate.        */
        bne 1f                          /* If != go to normal path.     */

        /* SRR1 had PR=0 and SRR1_PROGTM=1, so use the emergency stack  */
        andi.   r10,r12,MSR_PR;         /* Set CR0 correctly for label  */
                                        /* 3 in EXCEPTION_PROLOG_COMMON */
        mr      r10,r1                  /* Save r1                      */
        ld      r1,PACAEMERGSP(r13)     /* Use emergency stack          */
        subi    r1,r1,INT_FRAME_SIZE    /* alloc stack frame            */
        b 3f                            /* Jump into the macro !!       */
1:      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


EXC_REAL(fp_unavailable, 0x800, 0x100)
EXC_VIRT(fp_unavailable, 0x4800, 0x100, 0x800)
TRAMP_KVM(PACA_EXGEN, 0x800)
EXC_COMMON_BEGIN(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


EXC_REAL_OOL_MASKABLE(decrementer, 0x900, 0x80, IRQS_DISABLED)
EXC_VIRT_MASKABLE(decrementer, 0x4900, 0x80, 0x900, IRQS_DISABLED)
TRAMP_KVM(PACA_EXGEN, 0x900)
EXC_COMMON_ASYNC(decrementer_common, 0x900, timer_interrupt)


EXC_REAL_HV(hdecrementer, 0x980, 0x80)
EXC_VIRT_HV(hdecrementer, 0x4980, 0x80, 0x980)
TRAMP_KVM_HV(PACA_EXGEN, 0x980)
EXC_COMMON(hdecrementer_common, 0x980, hdec_interrupt)


EXC_REAL_MASKABLE(doorbell_super, 0xa00, 0x100, IRQS_DISABLED)
EXC_VIRT_MASKABLE(doorbell_super, 0x4a00, 0x100, 0xa00, IRQS_DISABLED)
TRAMP_KVM(PACA_EXGEN, 0xa00)
#ifdef CONFIG_PPC_DOORBELL
EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, doorbell_exception)
#else
EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, unknown_exception)
#endif


EXC_REAL(trap_0b, 0xb00, 0x100)
EXC_VIRT(trap_0b, 0x4b00, 0x100, 0xb00)
TRAMP_KVM(PACA_EXGEN, 0xb00)
EXC_COMMON(trap_0b_common, 0xb00, unknown_exception)

/*
 * system call / hypercall (0xc00, 0x4c00)
 *
 * The system call exception is invoked with "sc 0" and does not alter HV bit.
 * There is support for kernel code to invoke system calls but there are no
 * in-tree users.
 *
 * The hypercall is invoked with "sc 1" and sets HV=1.
 *
 * In HPT, sc 1 always goes to 0xc00 real mode. In RADIX, sc 1 can go to
 * 0x4c00 virtual mode.
 *
 * Call convention:
 *
 * syscall register convention is in Documentation/powerpc/syscall64-abi.txt
 *
 * For hypercalls, the register convention is as follows:
 * r0 volatile
 * r1-2 nonvolatile
 * r3 volatile parameter and return value for status
 * r4-r10 volatile input and output value
 * r11 volatile hypercall number and output value
 * r12 volatile input and output value
 * r13-r31 nonvolatile
 * LR nonvolatile
 * CTR volatile
 * XER volatile
 * CR0-1 CR5-7 volatile
 * CR2-4 nonvolatile
 * Other registers nonvolatile
 *
 * The intersection of volatile registers that don't contain possible
 * inputs is: cr0, xer, ctr. We may use these as scratch regs upon entry
 * without saving, though xer is not a good idea to use, as hardware may
 * interpret some bits so it may be costly to change them.
 */
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
        /*
         * There is a little bit of juggling to get syscall and hcall
         * working well. Save r13 in ctr to avoid using SPRG scratch
         * register.
         *
         * Userspace syscalls have already saved the PPR, hcalls must save
         * it before setting HMT_MEDIUM.
         */
#define SYSCALL_KVMTEST                                                 \
        mtctr   r13;                                                    \
        GET_PACA(r13);                                                  \
        std     r10,PACA_EXGEN+EX_R10(r13);                             \
        INTERRUPT_TO_KERNEL;                                            \
        KVMTEST EXC_STD 0xc00 ; /* uses r10, branch to do_kvm_0xc00_system_call */ \
        HMT_MEDIUM;                                                     \
        mfctr   r9;

#else
#define SYSCALL_KVMTEST                                                 \
        HMT_MEDIUM;                                                     \
        mr      r9,r13;                                                 \
        GET_PACA(r13);                                                  \
        INTERRUPT_TO_KERNEL;
#endif
        
#define LOAD_SYSCALL_HANDLER(reg)                                       \
        __LOAD_HANDLER(reg, system_call_common)

/*
 * After SYSCALL_KVMTEST, we reach here with PACA in r13, r13 in r9,
 * and HMT_MEDIUM.
 */
#define SYSCALL_REAL                                            \
        mfspr   r11,SPRN_SRR0 ;                                 \
        mfspr   r12,SPRN_SRR1 ;                                 \
        LOAD_SYSCALL_HANDLER(r10) ;                             \
        mtspr   SPRN_SRR0,r10 ;                                 \
        ld      r10,PACAKMSR(r13) ;                             \
        mtspr   SPRN_SRR1,r10 ;                                 \
        RFI_TO_KERNEL ;                                         \
        b       . ;     /* prevent speculative execution */

#ifdef CONFIG_PPC_FAST_ENDIAN_SWITCH
#define SYSCALL_FASTENDIAN_TEST                                 \
BEGIN_FTR_SECTION                                               \
        cmpdi   r0,0x1ebe ;                                     \
        beq-    1f ;                                            \
END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)                          \

#define SYSCALL_FASTENDIAN                                      \
        /* Fast LE/BE switch system call */                     \
1:      mfspr   r12,SPRN_SRR1 ;                                 \
        xori    r12,r12,MSR_LE ;                                \
        mtspr   SPRN_SRR1,r12 ;                                 \
        mr      r13,r9 ;                                        \
        RFI_TO_USER ;   /* return to userspace */               \
        b       . ;     /* prevent speculative execution */
#else
#define SYSCALL_FASTENDIAN_TEST
#define SYSCALL_FASTENDIAN
#endif /* CONFIG_PPC_FAST_ENDIAN_SWITCH */

#if defined(CONFIG_RELOCATABLE)
        /*
         * We can't branch directly so we do it via the CTR which
         * is volatile across system calls.
         */
#define SYSCALL_VIRT                                            \
        LOAD_SYSCALL_HANDLER(r10) ;                             \
        mtctr   r10 ;                                           \
        mfspr   r11,SPRN_SRR0 ;                                 \
        mfspr   r12,SPRN_SRR1 ;                                 \
        li      r10,MSR_RI ;                                    \
        mtmsrd  r10,1 ;                                         \
        bctr ;
#else
        /* We can branch directly */
#define SYSCALL_VIRT                                            \
        mfspr   r11,SPRN_SRR0 ;                                 \
        mfspr   r12,SPRN_SRR1 ;                                 \
        li      r10,MSR_RI ;                                    \
        mtmsrd  r10,1 ;                 /* Set RI (EE=0) */     \
        b       system_call_common ;
#endif

EXC_REAL_BEGIN(system_call, 0xc00, 0x100)
        SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
        SYSCALL_FASTENDIAN_TEST
        SYSCALL_REAL
        SYSCALL_FASTENDIAN
EXC_REAL_END(system_call, 0xc00, 0x100)

EXC_VIRT_BEGIN(system_call, 0x4c00, 0x100)
        SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
        SYSCALL_FASTENDIAN_TEST
        SYSCALL_VIRT
        SYSCALL_FASTENDIAN
EXC_VIRT_END(system_call, 0x4c00, 0x100)

#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
        /*
         * This is a hcall, so register convention is as above, with these
         * differences:
         * r13 = PACA
         * ctr = orig r13
         * orig r10 saved in PACA
         */
TRAMP_KVM_BEGIN(do_kvm_0xc00)
         /*
          * 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).
          */
        OPT_GET_SPR(r10, SPRN_PPR, CPU_FTR_HAS_PPR)
        HMT_MEDIUM
        OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r10, CPU_FTR_HAS_PPR)
        mfctr   r10
        SET_SCRATCH0(r10)
        std     r9,PACA_EXGEN+EX_R9(r13)
        mfcr    r9
        KVM_HANDLER PACA_EXGEN, EXC_STD, 0xc00, 0
#endif


EXC_REAL(single_step, 0xd00, 0x100)
EXC_VIRT(single_step, 0x4d00, 0x100, 0xd00)
TRAMP_KVM(PACA_EXGEN, 0xd00)
EXC_COMMON(single_step_common, 0xd00, single_step_exception)

EXC_REAL_OOL_HV(h_data_storage, 0xe00, 0x20)
EXC_VIRT_OOL_HV(h_data_storage, 0x4e00, 0x20, 0xe00)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0xe00)
EXC_COMMON_BEGIN(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
BEGIN_MMU_FTR_SECTION
        ld      r4,PACA_EXGEN+EX_DAR(r13)
        lwz     r5,PACA_EXGEN+EX_DSISR(r13)
        std     r4,_DAR(r1)
        std     r5,_DSISR(r1)
        li      r5,SIGSEGV
        bl      bad_page_fault
MMU_FTR_SECTION_ELSE
        bl      unknown_exception
ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_TYPE_RADIX)
        b       ret_from_except


EXC_REAL_OOL_HV(h_instr_storage, 0xe20, 0x20)
EXC_VIRT_OOL_HV(h_instr_storage, 0x4e20, 0x20, 0xe20)
TRAMP_KVM_HV(PACA_EXGEN, 0xe20)
EXC_COMMON(h_instr_storage_common, 0xe20, unknown_exception)


EXC_REAL_OOL_HV(emulation_assist, 0xe40, 0x20)
EXC_VIRT_OOL_HV(emulation_assist, 0x4e40, 0x20, 0xe40)
TRAMP_KVM_HV(PACA_EXGEN, 0xe40)
EXC_COMMON(emulation_assist_common, 0xe40, emulation_assist_interrupt)


/*
 * hmi_exception trampoline is a special case. It jumps to hmi_exception_early
 * first, and then eventaully from there to the trampoline to get into virtual
 * mode.
 */
__EXC_REAL_OOL_HV_DIRECT(hmi_exception, 0xe60, 0x20, hmi_exception_early)
__TRAMP_REAL_OOL_MASKABLE_HV(hmi_exception, 0xe60, IRQS_DISABLED)
EXC_VIRT_NONE(0x4e60, 0x20)
TRAMP_KVM_HV(PACA_EXGEN, 0xe60)
TRAMP_REAL_BEGIN(hmi_exception_early)
        EXCEPTION_PROLOG_1 EXC_HV, PACA_EXGEN, 1, 0xe60, 0
        mr      r10,r1                  /* Save r1 */
        ld      r1,PACAEMERGSP(r13)     /* Use emergency stack for realmode */
        subi    r1,r1,INT_FRAME_SIZE    /* alloc stack frame            */
        mfspr   r11,SPRN_HSRR0          /* Save HSRR0 */
        mfspr   r12,SPRN_HSRR1          /* Save HSRR1 */
        EXCEPTION_PROLOG_COMMON_1()
        /* We don't touch AMR here, we never go to virtual mode */
        EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
        EXCEPTION_PROLOG_COMMON_3(0xe60)
        addi    r3,r1,STACK_FRAME_OVERHEAD
        BRANCH_LINK_TO_FAR(DOTSYM(hmi_exception_realmode)) /* Function call ABI */
        cmpdi   cr0,r3,0

        /* 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)
        REST_2GPRS(12, r1)
        bne     1f
        mtcr    r11
        REST_GPR(11, r1)
        ld      r1,GPR1(r1)
        HRFI_TO_USER_OR_KERNEL

1:      mtcr    r11
        REST_GPR(11, 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       tramp_real_hmi_exception

EXC_COMMON_BEGIN(hmi_exception_common)
        EXCEPTION_COMMON(PACA_EXGEN, 0xe60)
        FINISH_NAP
        bl      save_nvgprs
        RECONCILE_IRQ_STATE(r10, r11)
        RUNLATCH_ON
        addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      handle_hmi_exception
        b       ret_from_except

EXC_REAL_OOL_MASKABLE_HV(h_doorbell, 0xe80, 0x20, IRQS_DISABLED)
EXC_VIRT_OOL_MASKABLE_HV(h_doorbell, 0x4e80, 0x20, 0xe80, IRQS_DISABLED)
TRAMP_KVM_HV(PACA_EXGEN, 0xe80)
#ifdef CONFIG_PPC_DOORBELL
EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, doorbell_exception)
#else
EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, unknown_exception)
#endif


EXC_REAL_OOL_MASKABLE_HV(h_virt_irq, 0xea0, 0x20, IRQS_DISABLED)
EXC_VIRT_OOL_MASKABLE_HV(h_virt_irq, 0x4ea0, 0x20, 0xea0, IRQS_DISABLED)
TRAMP_KVM_HV(PACA_EXGEN, 0xea0)
EXC_COMMON_ASYNC(h_virt_irq_common, 0xea0, do_IRQ)


EXC_REAL_NONE(0xec0, 0x20)
EXC_VIRT_NONE(0x4ec0, 0x20)
EXC_REAL_NONE(0xee0, 0x20)
EXC_VIRT_NONE(0x4ee0, 0x20)


EXC_REAL_OOL_MASKABLE(performance_monitor, 0xf00, 0x20, IRQS_PMI_DISABLED)
EXC_VIRT_OOL_MASKABLE(performance_monitor, 0x4f00, 0x20, 0xf00, IRQS_PMI_DISABLED)
TRAMP_KVM(PACA_EXGEN, 0xf00)
EXC_COMMON_ASYNC(performance_monitor_common, 0xf00, performance_monitor_exception)


EXC_REAL_OOL(altivec_unavailable, 0xf20, 0x20)
EXC_VIRT_OOL(altivec_unavailable, 0x4f20, 0x20, 0xf20)
TRAMP_KVM(PACA_EXGEN, 0xf20)
EXC_COMMON_BEGIN(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


EXC_REAL_OOL(vsx_unavailable, 0xf40, 0x20)
EXC_VIRT_OOL(vsx_unavailable, 0x4f40, 0x20, 0xf40)
TRAMP_KVM(PACA_EXGEN, 0xf40)
EXC_COMMON_BEGIN(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


EXC_REAL_OOL(facility_unavailable, 0xf60, 0x20)
EXC_VIRT_OOL(facility_unavailable, 0x4f60, 0x20, 0xf60)
TRAMP_KVM(PACA_EXGEN, 0xf60)
EXC_COMMON(facility_unavailable_common, 0xf60, facility_unavailable_exception)


EXC_REAL_OOL_HV(h_facility_unavailable, 0xf80, 0x20)
EXC_VIRT_OOL_HV(h_facility_unavailable, 0x4f80, 0x20, 0xf80)
TRAMP_KVM_HV(PACA_EXGEN, 0xf80)
EXC_COMMON(h_facility_unavailable_common, 0xf80, facility_unavailable_exception)


EXC_REAL_NONE(0xfa0, 0x20)
EXC_VIRT_NONE(0x4fa0, 0x20)
EXC_REAL_NONE(0xfc0, 0x20)
EXC_VIRT_NONE(0x4fc0, 0x20)
EXC_REAL_NONE(0xfe0, 0x20)
EXC_VIRT_NONE(0x4fe0, 0x20)

EXC_REAL_NONE(0x1000, 0x100)
EXC_VIRT_NONE(0x5000, 0x100)
EXC_REAL_NONE(0x1100, 0x100)
EXC_VIRT_NONE(0x5100, 0x100)

#ifdef CONFIG_CBE_RAS
EXC_REAL_HV(cbe_system_error, 0x1200, 0x100)
EXC_VIRT_NONE(0x5200, 0x100)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1200)
EXC_COMMON(cbe_system_error_common, 0x1200, cbe_system_error_exception)
#else /* CONFIG_CBE_RAS */
EXC_REAL_NONE(0x1200, 0x100)
EXC_VIRT_NONE(0x5200, 0x100)
#endif


EXC_REAL(instruction_breakpoint, 0x1300, 0x100)
EXC_VIRT(instruction_breakpoint, 0x5300, 0x100, 0x1300)
TRAMP_KVM_SKIP(PACA_EXGEN, 0x1300)
EXC_COMMON(instruction_breakpoint_common, 0x1300, instruction_breakpoint_exception)

EXC_REAL_NONE(0x1400, 0x100)
EXC_VIRT_NONE(0x5400, 0x100)

EXC_REAL_BEGIN(denorm_exception_hv, 0x1500, 0x100)
        mtspr   SPRN_SPRG_HSCRATCH0,r13
        EXCEPTION_PROLOG_0 PACA_EXGEN
        EXCEPTION_PROLOG_1 EXC_HV, PACA_EXGEN, 0, 0x1500, 0

#ifdef CONFIG_PPC_DENORMALISATION
        mfspr   r10,SPRN_HSRR1
        andis.  r10,r10,(HSRR1_DENORM)@h /* denorm? */
        bne+    denorm_assist
#endif

        KVMTEST EXC_HV 0x1500
        EXCEPTION_PROLOG_2_REAL denorm_common, EXC_HV, 1
EXC_REAL_END(denorm_exception_hv, 0x1500, 0x100)

#ifdef CONFIG_PPC_DENORMALISATION
EXC_VIRT_BEGIN(denorm_exception, 0x5500, 0x100)
        b       exc_real_0x1500_denorm_exception_hv
EXC_VIRT_END(denorm_exception, 0x5500, 0x100)
#else
EXC_VIRT_NONE(0x5500, 0x100)
#endif

TRAMP_KVM_HV(PACA_EXGEN, 0x1500)

#ifdef CONFIG_PPC_DENORMALISATION
TRAMP_REAL_BEGIN(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:
        mfspr   r11,SPRN_HSRR0
        subi    r11,r11,4
        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)
        HRFI_TO_UNKNOWN
        b       .
#endif

EXC_COMMON(denorm_common, 0x1500, unknown_exception)


#ifdef CONFIG_CBE_RAS
EXC_REAL_HV(cbe_maintenance, 0x1600, 0x100)
EXC_VIRT_NONE(0x5600, 0x100)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1600)
EXC_COMMON(cbe_maintenance_common, 0x1600, cbe_maintenance_exception)
#else /* CONFIG_CBE_RAS */
EXC_REAL_NONE(0x1600, 0x100)
EXC_VIRT_NONE(0x5600, 0x100)
#endif


EXC_REAL(altivec_assist, 0x1700, 0x100)
EXC_VIRT(altivec_assist, 0x5700, 0x100, 0x1700)
TRAMP_KVM(PACA_EXGEN, 0x1700)
#ifdef CONFIG_ALTIVEC
EXC_COMMON(altivec_assist_common, 0x1700, altivec_assist_exception)
#else
EXC_COMMON(altivec_assist_common, 0x1700, unknown_exception)
#endif


#ifdef CONFIG_CBE_RAS
EXC_REAL_HV(cbe_thermal, 0x1800, 0x100)
EXC_VIRT_NONE(0x5800, 0x100)
TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1800)
EXC_COMMON(cbe_thermal_common, 0x1800, cbe_thermal_exception)
#else /* CONFIG_CBE_RAS */
EXC_REAL_NONE(0x1800, 0x100)
EXC_VIRT_NONE(0x5800, 0x100)
#endif

#ifdef CONFIG_PPC_WATCHDOG

#define MASKED_DEC_HANDLER_LABEL 3f

#define MASKED_DEC_HANDLER(_H)                          \
3: /* soft-nmi */                                       \
        std     r12,PACA_EXGEN+EX_R12(r13);             \
        GET_SCRATCH0(r10);                              \
        std     r10,PACA_EXGEN+EX_R13(r13);             \
        EXCEPTION_PROLOG_2_REAL soft_nmi_common, _H, 1

/*
 * Branch to soft_nmi_interrupt using the emergency stack. The emergency
 * stack is one that is usable by maskable interrupts so long as MSR_EE
 * remains off. It is used for recovery when something has corrupted the
 * normal kernel stack, for example. The "soft NMI" must not use the process
 * stack because we want irq disabled sections to avoid touching the stack
 * at all (other than PMU interrupts), so use the emergency stack for this,
 * and run it entirely with interrupts hard disabled.
 */
EXC_COMMON_BEGIN(soft_nmi_common)
        mr      r10,r1
        ld      r1,PACAEMERGSP(r13)
        subi    r1,r1,INT_FRAME_SIZE
        EXCEPTION_COMMON_STACK(PACA_EXGEN, 0x900)
        bl      save_nvgprs
        RECONCILE_IRQ_STATE(r10, r11)
        addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      soft_nmi_interrupt
        b       ret_from_except

#else /* CONFIG_PPC_WATCHDOG */
#define MASKED_DEC_HANDLER_LABEL 2f /* normal return */
#define MASKED_DEC_HANDLER(_H)
#endif /* CONFIG_PPC_WATCHDOG */

/*
 * 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 it is one of PACA_IRQ_MUST_HARD_MASK, so hard disable and return.
 * This is called with r10 containing the value to OR to the paca field.
 */
.macro MASKED_INTERRUPT hsrr
        .if \hsrr
masked_Hinterrupt:
        .else
masked_interrupt:
        .endif
        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       MASKED_DEC_HANDLER_LABEL
1:      andi.   r10,r10,PACA_IRQ_MUST_HARD_MASK
        beq     2f
        .if \hsrr
        mfspr   r10,SPRN_HSRR1
        xori    r10,r10,MSR_EE  /* clear MSR_EE */
        mtspr   SPRN_HSRR1,r10
        .else
        mfspr   r10,SPRN_SRR1
        xori    r10,r10,MSR_EE  /* clear MSR_EE */
        mtspr   SPRN_SRR1,r10
        .endif
        ori     r11,r11,PACA_IRQ_HARD_DIS
        stb     r11,PACAIRQHAPPENED(r13)
2:      /* done */
        mtcrf   0x80,r9
        std     r1,PACAR1(r13)
        ld      r9,PACA_EXGEN+EX_R9(r13)
        ld      r10,PACA_EXGEN+EX_R10(r13)
        ld      r11,PACA_EXGEN+EX_R11(r13)
        /* returns to kernel where r13 must be set up, so don't restore it */
        .if \hsrr
        HRFI_TO_KERNEL
        .else
        RFI_TO_KERNEL
        .endif
        b       .
        MASKED_DEC_HANDLER(\hsrr\())
.endm

TRAMP_REAL_BEGIN(stf_barrier_fallback)
        std     r9,PACA_EXRFI+EX_R9(r13)
        std     r10,PACA_EXRFI+EX_R10(r13)
        sync
        ld      r9,PACA_EXRFI+EX_R9(r13)
        ld      r10,PACA_EXRFI+EX_R10(r13)
        ori     31,31,0
        .rept 14
        b       1f
1:
        .endr
        blr

TRAMP_REAL_BEGIN(rfi_flush_fallback)
        SET_SCRATCH0(r13);
        GET_PACA(r13);
        std     r1,PACA_EXRFI+EX_R12(r13)
        ld      r1,PACAKSAVE(r13)
        std     r9,PACA_EXRFI+EX_R9(r13)
        std     r10,PACA_EXRFI+EX_R10(r13)
        std     r11,PACA_EXRFI+EX_R11(r13)
        mfctr   r9
        ld      r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13)
        ld      r11,PACA_L1D_FLUSH_SIZE(r13)
        srdi    r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */
        mtctr   r11
        DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */

        /* order ld/st prior to dcbt stop all streams with flushing */
        sync

        /*
         * The load adresses are at staggered offsets within cachelines,
         * which suits some pipelines better (on others it should not
         * hurt).
         */
1:
        ld      r11,(0x80 + 8)*0(r10)
        ld      r11,(0x80 + 8)*1(r10)
        ld      r11,(0x80 + 8)*2(r10)
        ld      r11,(0x80 + 8)*3(r10)
        ld      r11,(0x80 + 8)*4(r10)
        ld      r11,(0x80 + 8)*5(r10)
        ld      r11,(0x80 + 8)*6(r10)
        ld      r11,(0x80 + 8)*7(r10)
        addi    r10,r10,0x80*8
        bdnz    1b

        mtctr   r9
        ld      r9,PACA_EXRFI+EX_R9(r13)
        ld      r10,PACA_EXRFI+EX_R10(r13)
        ld      r11,PACA_EXRFI+EX_R11(r13)
        ld      r1,PACA_EXRFI+EX_R12(r13)
        GET_SCRATCH0(r13);
        rfid

TRAMP_REAL_BEGIN(hrfi_flush_fallback)
        SET_SCRATCH0(r13);
        GET_PACA(r13);
        std     r1,PACA_EXRFI+EX_R12(r13)
        ld      r1,PACAKSAVE(r13)
        std     r9,PACA_EXRFI+EX_R9(r13)
        std     r10,PACA_EXRFI+EX_R10(r13)
        std     r11,PACA_EXRFI+EX_R11(r13)
        mfctr   r9
        ld      r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13)
        ld      r11,PACA_L1D_FLUSH_SIZE(r13)
        srdi    r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */
        mtctr   r11
        DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */

        /* order ld/st prior to dcbt stop all streams with flushing */
        sync

        /*
         * The load adresses are at staggered offsets within cachelines,
         * which suits some pipelines better (on others it should not
         * hurt).
         */
1:
        ld      r11,(0x80 + 8)*0(r10)
        ld      r11,(0x80 + 8)*1(r10)
        ld      r11,(0x80 + 8)*2(r10)
        ld      r11,(0x80 + 8)*3(r10)
        ld      r11,(0x80 + 8)*4(r10)
        ld      r11,(0x80 + 8)*5(r10)
        ld      r11,(0x80 + 8)*6(r10)
        ld      r11,(0x80 + 8)*7(r10)
        addi    r10,r10,0x80*8
        bdnz    1b

        mtctr   r9
        ld      r9,PACA_EXRFI+EX_R9(r13)
        ld      r10,PACA_EXRFI+EX_R10(r13)
        ld      r11,PACA_EXRFI+EX_R11(r13)
        ld      r1,PACA_EXRFI+EX_R12(r13)
        GET_SCRATCH0(r13);
        hrfid

/*
 * Real mode exceptions actually use this too, but alternate
 * instruction code patches (which end up in the common .text area)
 * cannot reach these if they are put there.
 */
USE_FIXED_SECTION(virt_trampolines)
        MASKED_INTERRUPT EXC_STD
        MASKED_INTERRUPT EXC_HV

#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
TRAMP_REAL_BEGIN(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)
        RFI_TO_KERNEL
        b       .

TRAMP_REAL_BEGIN(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)
        HRFI_TO_KERNEL
        b       .
#endif

/*
 * Ensure that any handlers that get invoked from the exception prologs
 * above are below the first 64KB (0x10000) of the kernel image because
 * the prologs assemble the addresses of these handlers using the
 * LOAD_HANDLER macro, which uses an ori instruction.
 */

/*** Common interrupt handlers ***/


        /*
         * 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.
         */

EXC_COMMON_BEGIN(ppc64_runlatch_on_trampoline)
        b       __ppc64_runlatch_on

USE_FIXED_SECTION(virt_trampolines)
        /*
         * The __end_interrupts marker must be past the out-of-line (OOL)
         * handlers, so that they are copied to real address 0x100 when running
         * a relocatable kernel. This ensures they can be reached from the short
         * trampoline handlers (like 0x4f00, 0x4f20, etc.) which branch
         * directly, without using LOAD_HANDLER().
         */
        .align  7
        .globl  __end_interrupts
__end_interrupts:
DEFINE_FIXED_SYMBOL(__end_interrupts)

#ifdef CONFIG_PPC_970_NAP
EXC_COMMON_BEGIN(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

CLOSE_FIXED_SECTION(real_vectors);
CLOSE_FIXED_SECTION(real_trampolines);
CLOSE_FIXED_SECTION(virt_vectors);
CLOSE_FIXED_SECTION(virt_trampolines);

USE_TEXT_SECTION()

/*
 * Hash table stuff
 */
        .balign IFETCH_ALIGN_BYTES
do_hash_page:
#ifdef CONFIG_PPC_BOOK3S_64
        lis     r0,(DSISR_BAD_FAULT_64S | DSISR_DABRMATCH | DSISR_KEYFAULT)@h
        ori     r0,r0,DSISR_BAD_FAULT_64S@l
        and.    r0,r4,r0                /* weird error? */
        bne-    handle_page_fault       /* if not, try to insert a HPTE */
        ld      r11, PACA_THREAD_INFO(r13)
        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 */

        /*
         * r3 contains the faulting address
         * r4 msr
         * r5 contains the trap number
         * r6 contains dsisr
         *
         * at return r3 = 0 for success, 1 for page fault, negative for error
         */
        mr      r4,r12
        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

        /* Reload DSISR into r4 for the DABR check below */
        ld      r4,_DSISR(r1)
#endif /* CONFIG_PPC_BOOK3S_64 */

/* Here we have a page fault that hash_page can't handle. */
handle_page_fault:
11:     andis.  r0,r4,DSISR_DABRMATCH@h
        bne-    handle_dabr_fault
        ld      r4,_DAR(r1)
        ld      r5,_DSISR(r1)
        addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      do_page_fault
        cmpdi   r3,0
        beq+    ret_from_except_lite
        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
        /*
         * do_break() may have changed the NV GPRS while handling a breakpoint.
         * If so, we need to restore them with their updated values. Don't use
         * ret_from_except_lite here.
         */
        b       ret_from_except


#ifdef CONFIG_PPC_BOOK3S_64
/* 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
#endif

/*
 * 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
_ASM_NOKPROBE_SYMBOL(bad_stack);

/*
 * When doorbell is triggered from system reset wakeup, the message is
 * not cleared, so it would fire again when EE is enabled.
 *
 * When coming from local_irq_enable, there may be the same problem if
 * we were hard disabled.
 *
 * Execute msgclr to clear pending exceptions before handling it.
 */
h_doorbell_common_msgclr:
        LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
        PPC_MSGCLR(3)
        b       h_doorbell_common

doorbell_super_common_msgclr:
        LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
        PPC_MSGCLRP(3)
        b       doorbell_super_common

/*
 * 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.
 *
 * Note that we don't specify LR as the NIP (return address) for
 * the interrupt because that would unbalance the return branch
 * predictor.
 */
_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
        LOAD_REG_ADDR(r11, replay_interrupt_return)
        mfcr    r9
        ori     r12,r12,MSR_EE
        cmpwi   r3,0x900
        beq     decrementer_common
        cmpwi   r3,0x500
BEGIN_FTR_SECTION
        beq     h_virt_irq_common
FTR_SECTION_ELSE
        beq     hardware_interrupt_common
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_300)
        cmpwi   r3,0xf00
        beq     performance_monitor_common
BEGIN_FTR_SECTION
        cmpwi   r3,0xa00
        beq     h_doorbell_common_msgclr
        cmpwi   r3,0xe60
        beq     hmi_exception_common
FTR_SECTION_ELSE
        cmpwi   r3,0xa00
        beq     doorbell_super_common_msgclr
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
replay_interrupt_return:
        blr

_ASM_NOKPROBE_SYMBOL(__replay_interrupt)