linux_kernel/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>

/*
 * 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)
#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)


#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.
	 */
#define IDLETEST(n)							\
	BEGIN_FTR_SECTION ;						\
	mfspr	r10,SPRN_SRR1 ;						\
	rlwinm.	r10,r10,47-31,30,31 ;					\
	beq-	1f ;							\
	cmpwi	cr3,r10,2 ;						\
	BRANCH_TO_C000(r10, system_reset_idle_common) ;			\
1:									\
	KVMTEST_PR(n) ;							\
	END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#else
#define IDLETEST NOTEST
#endif

EXC_REAL_BEGIN(system_reset, 0x100, 0x100)
	SET_SCRATCH0(r13)
	/*
	 * MSR_RI is not enabled, because PACA_EXNMI and nmi stack is
	 * being used, so a nested NMI exception would corrupt it.
	 */
	EXCEPTION_PROLOG_NORI(PACA_EXNMI, system_reset_common, EXC_STD,
			      IDLETEST, 0x100)

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)
	mfspr	r12,SPRN_SRR1
	b	pnv_powersave_wakeup
#endif

/*
 * 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.
 */
#define ADD_RECONCILE_NMI						\
	li	r10,IRQS_ALL_DISABLED;					\
	stb	r10,PACAIRQSOFTMASK(r13);				\
	lbz	r10,PACAIRQHAPPENED(r13);				\
	std	r10,_DAR(r1)

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_NORET_STACK(PACA_EXNMI, 0x100,
			system_reset, system_reset_exception,
			ADD_NVGPRS;ADD_RECONCILE_NMI)

	/* 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,
			      NOTEST, 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_powernv_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_powernv_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.
	 *
	 * 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 */
	/* 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 */
	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 */
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)

TRAMP_REAL_BEGIN(machine_check_pSeries)
	.globl machine_check_fwnmi
machine_check_fwnmi:
	SET_SCRATCH0(r13)		/* save r13 */
	EXCEPTION_PROLOG_0(PACA_EXMC)
machine_check_pSeries_0:
	EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST_PR, 0x200)
	/*
	 * 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_NORI(machine_check_common, EXC_STD)

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)

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

	/* Turn off the RI bit because SRR1 is used by idle wakeup code. */
	/* Recoverability could be improved by reducing the use of SRR1. */
	li	r11,0
	mtmsrd	r11,1

	b	pnv_powersave_wakeup_mce
#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)

#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
	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
	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 */
	/*
	 * 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
9:
	/* Deliver the machine check to host kernel in V mode. */
	MACHINE_CHECK_HANDLER_WINDUP
	b	machine_check_pSeries

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_REAL(data_access, 0x300, 0x80)
EXC_VIRT(data_access, 0x4300, 0x80, 0x300)
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.
	 */
	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
	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)
	EXCEPTION_PROLOG_0(PACA_EXSLB)
	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x380)
	mr	r12,r3	/* save r3 */
	mfspr	r3,SPRN_DAR
	mfspr	r11,SPRN_SRR1
	crset	4*cr6+eq
	BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_REAL_END(data_access_slb, 0x380, 0x80)

EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXSLB)
	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
	mr	r12,r3	/* save r3 */
	mfspr	r3,SPRN_DAR
	mfspr	r11,SPRN_SRR1
	crset	4*cr6+eq
	BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_VIRT_END(data_access_slb, 0x4380, 0x80)
TRAMP_KVM_SKIP(PACA_EXSLB, 0x380)


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)
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXSLB)
	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
	mr	r12,r3	/* save r3 */
	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
	mfspr	r11,SPRN_SRR1
	crclr	4*cr6+eq
	BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_REAL_END(instruction_access_slb, 0x480, 0x80)

EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXSLB)
	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
	mr	r12,r3	/* save r3 */
	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
	mfspr	r11,SPRN_SRR1
	crclr	4*cr6+eq
	BRANCH_TO_COMMON(r10, slb_miss_common)
EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)
TRAMP_KVM(PACA_EXSLB, 0x480)


/*
 * This handler is used by the 0x380 and 0x480 SLB miss interrupts, as well as
 * the virtual mode 0x4380 and 0x4480 interrupts if AIL is enabled.
 */
EXC_COMMON_BEGIN(slb_miss_common)
	/*
	 * r13 points to the PACA, r9 contains the saved CR,
	 * r12 contains the saved r3,
	 * r11 contain the saved SRR1, SRR0 is still ready for return
	 * r3 has the faulting address
	 * r9 - r13 are saved in paca->exslb.
 	 * cr6.eq is set for a D-SLB miss, clear for a I-SLB miss
	 * We assume we aren't going to take any exceptions during this
	 * procedure.
	 */
	mflr	r10
	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
	std	r10,PACA_EXSLB+EX_LR(r13)	/* save LR */

	andi.	r9,r11,MSR_PR	// Check for exception from userspace
	cmpdi	cr4,r9,MSR_PR	// And save the result in CR4 for later

	/*
	 * Test MSR_RI before calling slb_allocate_realmode, because the
	 * MSR in r11 gets clobbered. However we still want to allocate
	 * SLB in case MSR_RI=0, to minimise the risk of getting stuck in
	 * recursive SLB faults. So use cr5 for this, which is preserved.
	 */
	andi.	r11,r11,MSR_RI	/* check for unrecoverable exception */
	cmpdi	cr5,r11,MSR_RI

	crset	4*cr0+eq
#ifdef CONFIG_PPC_BOOK3S_64
BEGIN_MMU_FTR_SECTION
	bl	slb_allocate
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
#endif

	ld	r10,PACA_EXSLB+EX_LR(r13)
	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
	mtlr	r10

	/*
	 * Large address, check whether we have to allocate new contexts.
	 */
	beq-	8f

	bne-	cr5,2f		/* if unrecoverable exception, oops */

	/* All done -- return from exception. */

	bne	cr4,1f		/* returning to kernel */

	mtcrf	0x80,r9
	mtcrf	0x08,r9		/* MSR[PR] indication is in cr4 */
	mtcrf	0x04,r9		/* MSR[RI] indication is in cr5 */
	mtcrf	0x02,r9		/* I/D indication is in cr6 */
	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */

	RESTORE_CTR(r9, PACA_EXSLB)
	RESTORE_PPR_PACA(PACA_EXSLB, r9)
	mr	r3,r12
	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)
	RFI_TO_USER
	b	.	/* prevent speculative execution */
1:
	mtcrf	0x80,r9
	mtcrf	0x08,r9		/* MSR[PR] indication is in cr4 */
	mtcrf	0x04,r9		/* MSR[RI] indication is in cr5 */
	mtcrf	0x02,r9		/* I/D indication is in cr6 */
	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */

	RESTORE_CTR(r9, PACA_EXSLB)
	RESTORE_PPR_PACA(PACA_EXSLB, r9)
	mr	r3,r12
	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)
	RFI_TO_KERNEL
	b	.	/* prevent speculative execution */


2:	std     r3,PACA_EXSLB+EX_DAR(r13)
	mr	r3,r12
	mfspr	r11,SPRN_SRR0
	mfspr	r12,SPRN_SRR1
	LOAD_HANDLER(r10,unrecov_slb)
	mtspr	SPRN_SRR0,r10
	ld	r10,PACAKMSR(r13)
	mtspr	SPRN_SRR1,r10
	RFI_TO_KERNEL
	b	.

8:	std     r3,PACA_EXSLB+EX_DAR(r13)
	mr	r3,r12
	mfspr	r11,SPRN_SRR0
	mfspr	r12,SPRN_SRR1
	LOAD_HANDLER(r10, large_addr_slb)
	mtspr	SPRN_SRR0,r10
	ld	r10,PACAKMSR(r13)
	mtspr	SPRN_SRR1,r10
	RFI_TO_KERNEL
	b	.

EXC_COMMON_BEGIN(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

EXC_COMMON_BEGIN(large_addr_slb)
	EXCEPTION_PROLOG_COMMON(0x380, PACA_EXSLB)
	RECONCILE_IRQ_STATE(r10, r11)
	ld	r3, PACA_EXSLB+EX_DAR(r13)
	std	r3, _DAR(r1)
	beq	cr6, 2f
	li	r10, 0x481		/* fix trap number for I-SLB miss */
	std	r10, _TRAP(r1)
2:	bl	save_nvgprs
	addi	r3, r1, STACK_FRAME_OVERHEAD
	bl	slb_miss_large_addr
	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, SOFTEN_TEST_PR, 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(alignment, 0x600, 0x100)
EXC_VIRT(alignment, 0x4600, 0x100, 0x600)
TRAMP_KVM(PACA_EXGEN, 0x600)
EXC_COMMON_BEGIN(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


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_PR(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)
#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
	bl      unknown_exception
	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(PACA_EXGEN, KVMTEST_HV, 0xe60)
	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()
	EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
	EXCEPTION_PROLOG_COMMON_3(0xe60)
	addi	r3,r1,STACK_FRAME_OVERHEAD
	BRANCH_LINK_TO_FAR(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, hmi_exception_common, handle_hmi_exception,
        ret_from_except, FINISH_NAP;ADD_NVGPRS;ADD_RECONCILE;RUNLATCH_ON)

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(PACA_EXGEN, NOTEST, 0x1500)

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

	KVMTEST_HV(0x1500)
	EXCEPTION_PROLOG_2(denorm_common, EXC_HV)
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(soft_nmi_common, _H)

/*
 * 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_NORET_STACK(PACA_EXGEN, 0x900,
			system_reset, soft_nmi_interrupt,
			ADD_NVGPRS;ADD_RECONCILE)
	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.
 */
#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	MASKED_DEC_HANDLER_LABEL;		\
1:	andi.	r10,r10,PACA_IRQ_MUST_HARD_MASK;	\
	beq	2f;					\
	mfspr	r10,SPRN_##_H##SRR1;			\
	xori	r10,r10,MSR_EE; /* clear MSR_EE */	\
	mtspr	SPRN_##_H##SRR1,r10;			\
	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 */ \
	##_H##RFI_TO_KERNEL;				\
	b	.;					\
	MASKED_DEC_HANDLER(_H)

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()
	MASKED_INTERRUPT(H)

#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 */
	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 */

	/*
	 * 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+	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


#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)