[mirror_ubuntu-zesty-kernel.git] / arch / powerpc / kernel / exceptions-64s.S

/*
 * 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>

/*
 * We layout physical memory as follows:
 * 0x0000 - 0x00ff : Secondary processor spin code
 * 0x0100 - 0x17ff : pSeries Interrupt prologs
 * 0x1800 - 0x4000 : interrupt support common interrupt prologs
 * 0x4000 - 0x5fff : pSeries interrupts with IR=1,DR=1
 * 0x6000 - 0x6fff : more interrupt support including for IR=1,DR=1
 * 0x7000 - 0x7fff : FWNMI data area
 * 0x8000 - 0x8fff : Initial (CPU0) segment table
 * 0x9000 -        : Early init and support code
 */
	/* Syscall routine is used twice, in reloc-off and reloc-on paths */
#define SYSCALL_PSERIES_1 					\
BEGIN_FTR_SECTION						\
	cmpdi	r0,0x1ebe ; 					\
	beq-	1f ;						\
END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)				\
	mr	r9,r13 ;					\
	GET_PACA(r13) ;						\
	mfspr	r11,SPRN_SRR0 ;					\
0:

#define SYSCALL_PSERIES_2_RFID 					\
	mfspr	r12,SPRN_SRR1 ;					\
	ld	r10,PACAKBASE(r13) ; 				\
	LOAD_HANDLER(r10, system_call_entry) ; 			\
	mtspr	SPRN_SRR0,r10 ; 				\
	ld	r10,PACAKMSR(r13) ;				\
	mtspr	SPRN_SRR1,r10 ; 				\
	rfid ; 							\
	b	. ;	/* prevent speculative execution */

#define SYSCALL_PSERIES_3					\
	/* Fast LE/BE switch system call */			\
1:	mfspr	r12,SPRN_SRR1 ;					\
	xori	r12,r12,MSR_LE ;				\
	mtspr	SPRN_SRR1,r12 ;					\
	rfid ;		/* return to userspace */		\
	b	. ;						\
2:	mfspr	r12,SPRN_SRR1 ;					\
	andi.	r12,r12,MSR_PR ;				\
	bne	0b ;						\
	mtspr	SPRN_SRR0,r3 ;					\
	mtspr	SPRN_SRR1,r4 ;					\
	mtspr	SPRN_SDR1,r5 ;					\
	rfid ;							\
	b	. ;	/* prevent speculative execution */

#if defined(CONFIG_RELOCATABLE)
	/*
	 * We can't branch directly; in the direct case we use LR
	 * and system_call_entry restores LR.  (We thus need to move
	 * LR to r10 in the RFID case too.)
	 */
#define SYSCALL_PSERIES_2_DIRECT				\
	mflr	r10 ;						\
	ld	r12,PACAKBASE(r13) ; 				\
	LOAD_HANDLER(r12, system_call_entry_direct) ;		\
	mtlr	r12 ;						\
	mfspr	r12,SPRN_SRR1 ;					\
	/* Re-use of r13... No spare regs to do this */	\
	li	r13,MSR_RI ;					\
	mtmsrd 	r13,1 ;						\
	GET_PACA(r13) ;	/* get r13 back */			\
	blr ;
#else
	/* We can branch directly */
#define SYSCALL_PSERIES_2_DIRECT				\
	mfspr	r12,SPRN_SRR1 ;					\
	li	r10,MSR_RI ;					\
	mtmsrd 	r10,1 ;			/* Set RI (EE=0) */	\
	b	system_call_entry_direct ;
#endif

/*
 * This is the start of the interrupt handlers for pSeries
 * This code runs with relocation off.
 * Code from here to __end_interrupts gets copied down to real
 * address 0x100 when we are running a relocatable kernel.
 * Therefore any relative branches in this section must only
 * branch to labels in this section.
 */
	. = 0x100
	.globl __start_interrupts
__start_interrupts:

	.globl system_reset_pSeries;
system_reset_pSeries:
	HMT_MEDIUM;
	SET_SCRATCH0(r13)
#ifdef CONFIG_PPC_P7_NAP
BEGIN_FTR_SECTION
	/* Running native on arch 2.06 or later, check if we are
	 * waking up from nap. We only handle no state loss and
	 * supervisor state loss. We do -not- handle hypervisor
	 * state loss at this time.
	 */
	mfspr	r13,SPRN_SRR1
	rlwinm.	r13,r13,47-31,30,31
	beq	9f

	/* waking up from powersave (nap) state */
	cmpwi	cr1,r13,2
	/* Total loss of HV state is fatal, we could try to use the
	 * PIR to locate a PACA, then use an emergency stack etc...
	 * but for now, let's just stay stuck here
	 */
	bgt	cr1,.
	GET_PACA(r13)

#ifdef CONFIG_KVM_BOOK3S_64_HV
	li	r0,KVM_HWTHREAD_IN_KERNEL
	stb	r0,HSTATE_HWTHREAD_STATE(r13)
	/* Order setting hwthread_state vs. testing hwthread_req */
	sync
	lbz	r0,HSTATE_HWTHREAD_REQ(r13)
	cmpwi	r0,0
	beq	1f
	b	kvm_start_guest
1:
#endif

	beq	cr1,2f
	b	.power7_wakeup_noloss
2:	b	.power7_wakeup_loss
9:
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#endif /* CONFIG_PPC_P7_NAP */
	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
				 NOTEST, 0x100)

	. = 0x200
machine_check_pSeries_1:
	/* This is moved out of line as it can be patched by FW, but
	 * some code path might still want to branch into the original
	 * vector
	 */
	b	machine_check_pSeries

	. = 0x300
	.globl data_access_pSeries
data_access_pSeries:
	HMT_MEDIUM
	SET_SCRATCH0(r13)
BEGIN_FTR_SECTION
	b	data_access_check_stab
data_access_not_stab:
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_SLB)
	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common, EXC_STD,
				 KVMTEST, 0x300)

	. = 0x380
	.globl data_access_slb_pSeries
data_access_slb_pSeries:
	HMT_MEDIUM
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x380)
	std	r3,PACA_EXSLB+EX_R3(r13)
	mfspr	r3,SPRN_DAR
#ifdef __DISABLED__
	/* Keep that around for when we re-implement dynamic VSIDs */
	cmpdi	r3,0
	bge	slb_miss_user_pseries
#endif /* __DISABLED__ */
	mfspr	r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
	b	.slb_miss_realmode
#else
	/*
	 * We can't just use a direct branch to .slb_miss_realmode
	 * because the distance from here to there depends on where
	 * the kernel ends up being put.
	 */
	mfctr	r11
	ld	r10,PACAKBASE(r13)
	LOAD_HANDLER(r10, .slb_miss_realmode)
	mtctr	r10
	bctr
#endif

	STD_EXCEPTION_PSERIES(0x400, 0x400, instruction_access)

	. = 0x480
	.globl instruction_access_slb_pSeries
instruction_access_slb_pSeries:
	HMT_MEDIUM
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
	std	r3,PACA_EXSLB+EX_R3(r13)
	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
#ifdef __DISABLED__
	/* Keep that around for when we re-implement dynamic VSIDs */
	cmpdi	r3,0
	bge	slb_miss_user_pseries
#endif /* __DISABLED__ */
	mfspr	r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
	b	.slb_miss_realmode
#else
	mfctr	r11
	ld	r10,PACAKBASE(r13)
	LOAD_HANDLER(r10, .slb_miss_realmode)
	mtctr	r10
	bctr
#endif

	/* We open code these as we can't have a ". = x" (even with
	 * x = "." within a feature section
	 */
	. = 0x500;
	.globl hardware_interrupt_pSeries;
	.globl hardware_interrupt_hv;
hardware_interrupt_pSeries:
hardware_interrupt_hv:
	BEGIN_FTR_SECTION
		_MASKABLE_EXCEPTION_PSERIES(0x502, hardware_interrupt,
					    EXC_HV, SOFTEN_TEST_HV)
		KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x502)
	FTR_SECTION_ELSE
		_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt,
					    EXC_STD, SOFTEN_TEST_HV_201)
		KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x500)
	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

	STD_EXCEPTION_PSERIES(0x600, 0x600, alignment)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x600)

	STD_EXCEPTION_PSERIES(0x700, 0x700, program_check)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x700)

	STD_EXCEPTION_PSERIES(0x800, 0x800, fp_unavailable)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x800)

	MASKABLE_EXCEPTION_PSERIES(0x900, 0x900, decrementer)
	STD_EXCEPTION_HV(0x980, 0x982, hdecrementer)

	MASKABLE_EXCEPTION_PSERIES(0xa00, 0xa00, doorbell_super)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xa00)

	STD_EXCEPTION_PSERIES(0xb00, 0xb00, trap_0b)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xb00)

	. = 0xc00
	.globl	system_call_pSeries
system_call_pSeries:
	HMT_MEDIUM
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
	SET_SCRATCH0(r13)
	GET_PACA(r13)
	std	r9,PACA_EXGEN+EX_R9(r13)
	std	r10,PACA_EXGEN+EX_R10(r13)
	mfcr	r9
	KVMTEST(0xc00)
	GET_SCRATCH0(r13)
#endif
	SYSCALL_PSERIES_1
	SYSCALL_PSERIES_2_RFID
	SYSCALL_PSERIES_3
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xc00)

	STD_EXCEPTION_PSERIES(0xd00, 0xd00, single_step)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xd00)

	/* At 0xe??? we have a bunch of hypervisor exceptions, we branch
	 * out of line to handle them
	 */
	. = 0xe00
hv_exception_trampoline:
	b	h_data_storage_hv
	. = 0xe20
	b	h_instr_storage_hv
	. = 0xe40
	b	emulation_assist_hv
	. = 0xe50
	b	hmi_exception_hv
	. = 0xe60
	b	hmi_exception_hv
	. = 0xe80
	b	h_doorbell_hv

	/* We need to deal with the Altivec unavailable exception
	 * here which is at 0xf20, thus in the middle of the
	 * prolog code of the PerformanceMonitor one. A little
	 * trickery is thus necessary
	 */
performance_monitor_pSeries_1:
	. = 0xf00
	b	performance_monitor_pSeries

altivec_unavailable_pSeries_1:
	. = 0xf20
	b	altivec_unavailable_pSeries

vsx_unavailable_pSeries_1:
	. = 0xf40
	b	vsx_unavailable_pSeries

#ifdef CONFIG_CBE_RAS
	STD_EXCEPTION_HV(0x1200, 0x1202, cbe_system_error)
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1202)
#endif /* CONFIG_CBE_RAS */

	STD_EXCEPTION_PSERIES(0x1300, 0x1300, instruction_breakpoint)
	KVM_HANDLER_PR_SKIP(PACA_EXGEN, EXC_STD, 0x1300)

	. = 0x1500
	.global denorm_exception_hv
denorm_exception_hv:
	HMT_MEDIUM
	mtspr	SPRN_SPRG_HSCRATCH0,r13
	mfspr	r13,SPRN_SPRG_HPACA
	std	r9,PACA_EXGEN+EX_R9(r13)
	std	r10,PACA_EXGEN+EX_R10(r13)
	std	r11,PACA_EXGEN+EX_R11(r13)
	std	r12,PACA_EXGEN+EX_R12(r13)
	mfspr	r9,SPRN_SPRG_HSCRATCH0
	std	r9,PACA_EXGEN+EX_R13(r13)
	mfcr	r9

#ifdef CONFIG_PPC_DENORMALISATION
	mfspr	r10,SPRN_HSRR1
	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */
	andis.	r10,r10,(HSRR1_DENORM)@h /* denorm? */
	addi	r11,r11,-4		/* HSRR0 is next instruction */
	bne+	denorm_assist
#endif

	EXCEPTION_PROLOG_PSERIES_1(denorm_common, EXC_HV)
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x1500)

#ifdef CONFIG_CBE_RAS
	STD_EXCEPTION_HV(0x1600, 0x1602, cbe_maintenance)
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1602)
#endif /* CONFIG_CBE_RAS */

	STD_EXCEPTION_PSERIES(0x1700, 0x1700, altivec_assist)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x1700)

#ifdef CONFIG_CBE_RAS
	STD_EXCEPTION_HV(0x1800, 0x1802, cbe_thermal)
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1802)
#else
	. = 0x1800
#endif /* CONFIG_CBE_RAS */


/*** Out of line interrupts support ***/

	.align	7
	/* moved from 0x200 */
machine_check_pSeries:
	.globl machine_check_fwnmi
machine_check_fwnmi:
	HMT_MEDIUM
	SET_SCRATCH0(r13)		/* save r13 */
	EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common,
				 EXC_STD, KVMTEST, 0x200)
	KVM_HANDLER_SKIP(PACA_EXMC, EXC_STD, 0x200)

	/* moved from 0x300 */
data_access_check_stab:
	GET_PACA(r13)
	std	r9,PACA_EXSLB+EX_R9(r13)
	std	r10,PACA_EXSLB+EX_R10(r13)
	mfspr	r10,SPRN_DAR
	mfspr	r9,SPRN_DSISR
	srdi	r10,r10,60
	rlwimi	r10,r9,16,0x20
#ifdef CONFIG_KVM_BOOK3S_PR
	lbz	r9,HSTATE_IN_GUEST(r13)
	rlwimi	r10,r9,8,0x300
#endif
	mfcr	r9
	cmpwi	r10,0x2c
	beq	do_stab_bolted_pSeries
	mtcrf	0x80,r9
	ld	r9,PACA_EXSLB+EX_R9(r13)
	ld	r10,PACA_EXSLB+EX_R10(r13)
	b	data_access_not_stab
do_stab_bolted_pSeries:
	std	r11,PACA_EXSLB+EX_R11(r13)
	std	r12,PACA_EXSLB+EX_R12(r13)
	GET_SCRATCH0(r10)
	std	r10,PACA_EXSLB+EX_R13(r13)
	EXCEPTION_PROLOG_PSERIES_1(.do_stab_bolted, EXC_STD)

	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x300)
	KVM_HANDLER_SKIP(PACA_EXSLB, EXC_STD, 0x380)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x400)
	KVM_HANDLER_PR(PACA_EXSLB, EXC_STD, 0x480)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x900)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x982)

#ifdef CONFIG_PPC_DENORMALISATION
denorm_assist:
BEGIN_FTR_SECTION
/*
 * To denormalise we need to move a copy of the register to itself.
 * For POWER6 do that here for all FP regs.
 */
	mfmsr	r10
	ori	r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
	xori	r10,r10,(MSR_FE0|MSR_FE1)
	mtmsrd	r10
	sync
	fmr	0,0
	fmr	1,1
	fmr	2,2
	fmr	3,3
	fmr	4,4
	fmr	5,5
	fmr	6,6
	fmr	7,7
	fmr	8,8
	fmr	9,9
	fmr	10,10
	fmr	11,11
	fmr	12,12
	fmr	13,13
	fmr	14,14
	fmr	15,15
	fmr	16,16
	fmr	17,17
	fmr	18,18
	fmr	19,19
	fmr	20,20
	fmr	21,21
	fmr	22,22
	fmr	23,23
	fmr	24,24
	fmr	25,25
	fmr	26,26
	fmr	27,27
	fmr	28,28
	fmr	29,29
	fmr	30,30
	fmr	31,31
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
	XVCPSGNDP(0,0,0)
	XVCPSGNDP(1,1,1)
	XVCPSGNDP(2,2,2)
	XVCPSGNDP(3,3,3)
	XVCPSGNDP(4,4,4)
	XVCPSGNDP(5,5,5)
	XVCPSGNDP(6,6,6)
	XVCPSGNDP(7,7,7)
	XVCPSGNDP(8,8,8)
	XVCPSGNDP(9,9,9)
	XVCPSGNDP(10,10,10)
	XVCPSGNDP(11,11,11)
	XVCPSGNDP(12,12,12)
	XVCPSGNDP(13,13,13)
	XVCPSGNDP(14,14,14)
	XVCPSGNDP(15,15,15)
	XVCPSGNDP(16,16,16)
	XVCPSGNDP(17,17,17)
	XVCPSGNDP(18,18,18)
	XVCPSGNDP(19,19,19)
	XVCPSGNDP(20,20,20)
	XVCPSGNDP(21,21,21)
	XVCPSGNDP(22,22,22)
	XVCPSGNDP(23,23,23)
	XVCPSGNDP(24,24,24)
	XVCPSGNDP(25,25,25)
	XVCPSGNDP(26,26,26)
	XVCPSGNDP(27,27,27)
	XVCPSGNDP(28,28,28)
	XVCPSGNDP(29,29,29)
	XVCPSGNDP(30,30,30)
	XVCPSGNDP(31,31,31)
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
	mtspr	SPRN_HSRR0,r11
	mtcrf	0x80,r9
	ld	r9,PACA_EXGEN+EX_R9(r13)
	ld	r10,PACA_EXGEN+EX_R10(r13)
	ld	r11,PACA_EXGEN+EX_R11(r13)
	ld	r12,PACA_EXGEN+EX_R12(r13)
	ld	r13,PACA_EXGEN+EX_R13(r13)
	HRFID
	b	.
#endif

	.align	7
	/* moved from 0xe00 */
	STD_EXCEPTION_HV(., 0xe02, h_data_storage)
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0xe02)
	STD_EXCEPTION_HV(., 0xe22, h_instr_storage)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe22)
	STD_EXCEPTION_HV(., 0xe42, emulation_assist)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe42)
	STD_EXCEPTION_HV(., 0xe62, hmi_exception) /* need to flush cache ? */
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe62)
	MASKABLE_EXCEPTION_HV(., 0xe82, h_doorbell)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe82)

	/* moved from 0xf00 */
	STD_EXCEPTION_PSERIES(., 0xf00, performance_monitor)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf00)
	STD_EXCEPTION_PSERIES(., 0xf20, altivec_unavailable)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf20)
	STD_EXCEPTION_PSERIES(., 0xf40, vsx_unavailable)
	KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf40)

/*
 * 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, else we hard disable and return. This is called with
 * r10 containing the value to OR to the paca field.
 */
#define MASKED_INTERRUPT(_H)				\
masked_##_H##interrupt:					\
	std	r11,PACA_EXGEN+EX_R11(r13);		\
	lbz	r11,PACAIRQHAPPENED(r13);		\
	or	r11,r11,r10;				\
	stb	r11,PACAIRQHAPPENED(r13);		\
	andi.	r10,r10,PACA_IRQ_DEC;			\
	beq	1f;					\
	lis	r10,0x7fff;				\
	ori	r10,r10,0xffff;				\
	mtspr	SPRN_DEC,r10;				\
	b	2f;					\
1:	mfspr	r10,SPRN_##_H##SRR1;			\
	rldicl	r10,r10,48,1; /* clear MSR_EE */	\
	rotldi	r10,r10,16;				\
	mtspr	SPRN_##_H##SRR1,r10;			\
2:	mtcrf	0x80,r9;				\
	ld	r9,PACA_EXGEN+EX_R9(r13);		\
	ld	r10,PACA_EXGEN+EX_R10(r13);		\
	ld	r11,PACA_EXGEN+EX_R11(r13);		\
	GET_SCRATCH0(r13);				\
	##_H##rfid;					\
	b	.
	
	MASKED_INTERRUPT()
	MASKED_INTERRUPT(H)

/*
 * Called from arch_local_irq_enable when an interrupt needs
 * to be resent. r3 contains 0x500 or 0x900 to indicate which
 * kind of interrupt. MSR:EE is already off. We generate a
 * stackframe like if a real interrupt had happened.
 *
 * Note: While MSR:EE is off, we need to make sure that _MSR
 * in the generated frame has EE set to 1 or the exception
 * handler will not properly re-enable them.
 */
_GLOBAL(__replay_interrupt)
	/* We are going to jump to the exception common code which
	 * will retrieve various register values from the PACA which
	 * we don't give a damn about, so we don't bother storing them.
	 */
	mfmsr	r12
	mflr	r11
	mfcr	r9
	ori	r12,r12,MSR_EE
	andi.	r3,r3,0x0800
	bne	decrementer_common
	b	hardware_interrupt_common

#ifdef CONFIG_PPC_PSERIES
/*
 * Vectors for the FWNMI option.  Share common code.
 */
	.globl system_reset_fwnmi
      .align 7
system_reset_fwnmi:
	HMT_MEDIUM
	SET_SCRATCH0(r13)		/* save r13 */
	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
				 NOTEST, 0x100)

#endif /* CONFIG_PPC_PSERIES */

#ifdef __DISABLED__
/*
 * This is used for when the SLB miss handler has to go virtual,
 * which doesn't happen for now anymore but will once we re-implement
 * dynamic VSIDs for shared page tables
 */
slb_miss_user_pseries:
	std	r10,PACA_EXGEN+EX_R10(r13)
	std	r11,PACA_EXGEN+EX_R11(r13)
	std	r12,PACA_EXGEN+EX_R12(r13)
	GET_SCRATCH0(r10)
	ld	r11,PACA_EXSLB+EX_R9(r13)
	ld	r12,PACA_EXSLB+EX_R3(r13)
	std	r10,PACA_EXGEN+EX_R13(r13)
	std	r11,PACA_EXGEN+EX_R9(r13)
	std	r12,PACA_EXGEN+EX_R3(r13)
	clrrdi	r12,r13,32
	mfmsr	r10
	mfspr	r11,SRR0			/* save SRR0 */
	ori	r12,r12,slb_miss_user_common@l	/* virt addr of handler */
	ori	r10,r10,MSR_IR|MSR_DR|MSR_RI
	mtspr	SRR0,r12
	mfspr	r12,SRR1			/* and SRR1 */
	mtspr	SRR1,r10
	rfid
	b	.				/* prevent spec. execution */
#endif /* __DISABLED__ */

/*
 * Code from here down to __end_handlers is invoked from the
 * exception prologs above.  Because the prologs assemble the
 * addresses of these handlers using the LOAD_HANDLER macro,
 * which uses an ori instruction, these handlers must be in
 * the first 64k of the kernel image.
 */

/*** Common interrupt handlers ***/

	STD_EXCEPTION_COMMON(0x100, system_reset, .system_reset_exception)

	/*
	 * Machine check is different because we use a different
	 * save area: PACA_EXMC instead of PACA_EXGEN.
	 */
	.align	7
	.globl machine_check_common
machine_check_common:
	EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
	FINISH_NAP
	DISABLE_INTS
	bl	.save_nvgprs
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.machine_check_exception
	b	.ret_from_except

	STD_EXCEPTION_COMMON_ASYNC(0x500, hardware_interrupt, do_IRQ)
	STD_EXCEPTION_COMMON_ASYNC(0x900, decrementer, .timer_interrupt)
	STD_EXCEPTION_COMMON(0x980, hdecrementer, .hdec_interrupt)
#ifdef CONFIG_PPC_DOORBELL
	STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, .doorbell_exception)
#else
	STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, .unknown_exception)
#endif
	STD_EXCEPTION_COMMON(0xb00, trap_0b, .unknown_exception)
	STD_EXCEPTION_COMMON(0xd00, single_step, .single_step_exception)
	STD_EXCEPTION_COMMON(0xe00, trap_0e, .unknown_exception)
	STD_EXCEPTION_COMMON(0xe40, emulation_assist, .program_check_exception)
	STD_EXCEPTION_COMMON(0xe60, hmi_exception, .unknown_exception)
#ifdef CONFIG_PPC_DOORBELL
	STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, .doorbell_exception)
#else
	STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, .unknown_exception)
#endif
	STD_EXCEPTION_COMMON_ASYNC(0xf00, performance_monitor, .performance_monitor_exception)
	STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, .instruction_breakpoint_exception)
	STD_EXCEPTION_COMMON(0x1502, denorm, .unknown_exception)
#ifdef CONFIG_ALTIVEC
	STD_EXCEPTION_COMMON(0x1700, altivec_assist, .altivec_assist_exception)
#else
	STD_EXCEPTION_COMMON(0x1700, altivec_assist, .unknown_exception)
#endif
#ifdef CONFIG_CBE_RAS
	STD_EXCEPTION_COMMON(0x1200, cbe_system_error, .cbe_system_error_exception)
	STD_EXCEPTION_COMMON(0x1600, cbe_maintenance, .cbe_maintenance_exception)
	STD_EXCEPTION_COMMON(0x1800, cbe_thermal, .cbe_thermal_exception)
#endif /* CONFIG_CBE_RAS */

	/*
	 * Relocation-on interrupts: A subset of the interrupts can be delivered
	 * with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
	 * it.  Addresses are the same as the original interrupt addresses, but
	 * offset by 0xc000000000004000.
	 * It's impossible to receive interrupts below 0x300 via this mechanism.
	 * KVM: None of these traps are from the guest ; anything that escalated
	 * to HV=1 from HV=0 is delivered via real mode handlers.
	 */

	/*
	 * This uses the standard macro, since the original 0x300 vector
	 * only has extra guff for STAB-based processors -- which never
	 * come here.
	 */
	STD_RELON_EXCEPTION_PSERIES(0x4300, 0x300, data_access)
	. = 0x4380
	.globl data_access_slb_relon_pSeries
data_access_slb_relon_pSeries:
	HMT_MEDIUM
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
	std	r3,PACA_EXSLB+EX_R3(r13)
	mfspr	r3,SPRN_DAR
	mfspr	r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
	b	.slb_miss_realmode
#else
	/*
	 * We can't just use a direct branch to .slb_miss_realmode
	 * because the distance from here to there depends on where
	 * the kernel ends up being put.
	 */
	mfctr	r11
	ld	r10,PACAKBASE(r13)
	LOAD_HANDLER(r10, .slb_miss_realmode)
	mtctr	r10
	bctr
#endif

	STD_RELON_EXCEPTION_PSERIES(0x4400, 0x400, instruction_access)
	. = 0x4480
	.globl instruction_access_slb_relon_pSeries
instruction_access_slb_relon_pSeries:
	HMT_MEDIUM
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
	std	r3,PACA_EXSLB+EX_R3(r13)
	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
	mfspr	r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
	b	.slb_miss_realmode
#else
	mfctr	r11
	ld	r10,PACAKBASE(r13)
	LOAD_HANDLER(r10, .slb_miss_realmode)
	mtctr	r10
	bctr
#endif

	. = 0x4500
	.globl hardware_interrupt_relon_pSeries;
	.globl hardware_interrupt_relon_hv;
hardware_interrupt_relon_pSeries:
hardware_interrupt_relon_hv:
	BEGIN_FTR_SECTION
		_MASKABLE_RELON_EXCEPTION_PSERIES(0x502, hardware_interrupt, EXC_HV, SOFTEN_TEST_HV)
	FTR_SECTION_ELSE
		_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt, EXC_STD, SOFTEN_TEST_PR)
	ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_206)
	STD_RELON_EXCEPTION_PSERIES(0x4600, 0x600, alignment)
	STD_RELON_EXCEPTION_PSERIES(0x4700, 0x700, program_check)
	STD_RELON_EXCEPTION_PSERIES(0x4800, 0x800, fp_unavailable)
	MASKABLE_RELON_EXCEPTION_PSERIES(0x4900, 0x900, decrementer)
	STD_RELON_EXCEPTION_HV(0x4980, 0x982, hdecrementer)
	MASKABLE_RELON_EXCEPTION_PSERIES(0x4a00, 0xa00, doorbell_super)
	STD_RELON_EXCEPTION_PSERIES(0x4b00, 0xb00, trap_0b)

	. = 0x4c00
	.globl system_call_relon_pSeries
system_call_relon_pSeries:
	HMT_MEDIUM
	SYSCALL_PSERIES_1
	SYSCALL_PSERIES_2_DIRECT
	SYSCALL_PSERIES_3

	STD_RELON_EXCEPTION_PSERIES(0x4d00, 0xd00, single_step)

	. = 0x4e00
	b	h_data_storage_relon_hv

	. = 0x4e20
	b	h_instr_storage_relon_hv

	. = 0x4e40
	b	emulation_assist_relon_hv

	. = 0x4e50
	b	hmi_exception_relon_hv

	. = 0x4e60
	b	hmi_exception_relon_hv

	. = 0x4e80
	b	h_doorbell_relon_hv

performance_monitor_relon_pSeries_1:
	. = 0x4f00
	b	performance_monitor_relon_pSeries

altivec_unavailable_relon_pSeries_1:
	. = 0x4f20
	b	altivec_unavailable_relon_pSeries

vsx_unavailable_relon_pSeries_1:
	. = 0x4f40
	b	vsx_unavailable_relon_pSeries

#ifdef CONFIG_CBE_RAS
	STD_RELON_EXCEPTION_HV(0x5200, 0x1202, cbe_system_error)
#endif /* CONFIG_CBE_RAS */
	STD_RELON_EXCEPTION_PSERIES(0x5300, 0x1300, instruction_breakpoint)
#ifdef CONFIG_PPC_DENORMALISATION
	. = 0x5500
	b	denorm_exception_hv
#endif
#ifdef CONFIG_CBE_RAS
	STD_RELON_EXCEPTION_HV(0x5600, 0x1602, cbe_maintenance)
#else
#ifdef CONFIG_HVC_SCOM
	STD_RELON_EXCEPTION_HV(0x5600, 0x1600, maintence_interrupt)
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1600)
#endif /* CONFIG_HVC_SCOM */
#endif /* CONFIG_CBE_RAS */
	STD_RELON_EXCEPTION_PSERIES(0x5700, 0x1700, altivec_assist)
#ifdef CONFIG_CBE_RAS
	STD_RELON_EXCEPTION_HV(0x5800, 0x1802, cbe_thermal)
#endif /* CONFIG_CBE_RAS */

	/* Other future vectors */
	.align	7
	.globl	__end_interrupts
__end_interrupts:

	.align	7
system_call_entry_direct:
#if defined(CONFIG_RELOCATABLE)
	/* The first level prologue may have used LR to get here, saving
	 * orig in r10.  To save hacking/ifdeffing common code, restore here.
	 */
	mtlr	r10
#endif
system_call_entry:
	b	system_call_common

ppc64_runlatch_on_trampoline:
	b	.__ppc64_runlatch_on

/*
 * 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

/*
 * Here r13 points to the paca, r9 contains the saved CR,
 * SRR0 and SRR1 are saved in r11 and r12,
 * r9 - r13 are saved in paca->exgen.
 */
	.align	7
	.globl data_access_common
data_access_common:
	mfspr	r10,SPRN_DAR
	std	r10,PACA_EXGEN+EX_DAR(r13)
	mfspr	r10,SPRN_DSISR
	stw	r10,PACA_EXGEN+EX_DSISR(r13)
	EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
	DISABLE_INTS
	ld	r12,_MSR(r1)
	ld	r3,PACA_EXGEN+EX_DAR(r13)
	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
	li	r5,0x300
	b	.do_hash_page		/* Try to handle as hpte fault */

	.align  7
	.globl  h_data_storage_common
h_data_storage_common:
	mfspr   r10,SPRN_HDAR
	std     r10,PACA_EXGEN+EX_DAR(r13)
	mfspr   r10,SPRN_HDSISR
	stw     r10,PACA_EXGEN+EX_DSISR(r13)
	EXCEPTION_PROLOG_COMMON(0xe00, PACA_EXGEN)
	bl      .save_nvgprs
	DISABLE_INTS
	addi    r3,r1,STACK_FRAME_OVERHEAD
	bl      .unknown_exception
	b       .ret_from_except

	.align	7
	.globl instruction_access_common
instruction_access_common:
	EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
	DISABLE_INTS
	ld	r12,_MSR(r1)
	ld	r3,_NIP(r1)
	andis.	r4,r12,0x5820
	li	r5,0x400
	b	.do_hash_page		/* Try to handle as hpte fault */

	STD_EXCEPTION_COMMON(0xe20, h_instr_storage, .unknown_exception)

/*
 * Here is the common SLB miss user that is used when going to virtual
 * mode for SLB misses, that is currently not used
 */
#ifdef __DISABLED__
	.align	7
	.globl	slb_miss_user_common
slb_miss_user_common:
	mflr	r10
	std	r3,PACA_EXGEN+EX_DAR(r13)
	stw	r9,PACA_EXGEN+EX_CCR(r13)
	std	r10,PACA_EXGEN+EX_LR(r13)
	std	r11,PACA_EXGEN+EX_SRR0(r13)
	bl	.slb_allocate_user

	ld	r10,PACA_EXGEN+EX_LR(r13)
	ld	r3,PACA_EXGEN+EX_R3(r13)
	lwz	r9,PACA_EXGEN+EX_CCR(r13)
	ld	r11,PACA_EXGEN+EX_SRR0(r13)
	mtlr	r10
	beq-	slb_miss_fault

	andi.	r10,r12,MSR_RI		/* check for unrecoverable exception */
	beq-	unrecov_user_slb
	mfmsr	r10

.machine push
.machine "power4"
	mtcrf	0x80,r9
.machine pop

	clrrdi	r10,r10,2		/* clear RI before setting SRR0/1 */
	mtmsrd	r10,1

	mtspr	SRR0,r11
	mtspr	SRR1,r12

	ld	r9,PACA_EXGEN+EX_R9(r13)
	ld	r10,PACA_EXGEN+EX_R10(r13)
	ld	r11,PACA_EXGEN+EX_R11(r13)
	ld	r12,PACA_EXGEN+EX_R12(r13)
	ld	r13,PACA_EXGEN+EX_R13(r13)
	rfid
	b	.

slb_miss_fault:
	EXCEPTION_PROLOG_COMMON(0x380, PACA_EXGEN)
	ld	r4,PACA_EXGEN+EX_DAR(r13)
	li	r5,0
	std	r4,_DAR(r1)
	std	r5,_DSISR(r1)
	b	handle_page_fault

unrecov_user_slb:
	EXCEPTION_PROLOG_COMMON(0x4200, PACA_EXGEN)
	DISABLE_INTS
	bl	.save_nvgprs
1:	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.unrecoverable_exception
	b	1b

#endif /* __DISABLED__ */


/*
 * r13 points to the PACA, r9 contains the saved CR,
 * r12 contain the saved SRR1, SRR0 is still ready for return
 * r3 has the faulting address
 * r9 - r13 are saved in paca->exslb.
 * r3 is saved in paca->slb_r3
 * We assume we aren't going to take any exceptions during this procedure.
 */
_GLOBAL(slb_miss_realmode)
	mflr	r10
#ifdef CONFIG_RELOCATABLE
	mtctr	r11
#endif

	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
	std	r10,PACA_EXSLB+EX_LR(r13)	/* save LR */

	bl	.slb_allocate_realmode

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

	ld	r10,PACA_EXSLB+EX_LR(r13)
	ld	r3,PACA_EXSLB+EX_R3(r13)
	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */

	mtlr	r10

	andi.	r10,r12,MSR_RI	/* check for unrecoverable exception */
	beq-	2f

.machine	push
.machine	"power4"
	mtcrf	0x80,r9
	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */
.machine	pop

	ld	r9,PACA_EXSLB+EX_R9(r13)
	ld	r10,PACA_EXSLB+EX_R10(r13)
	ld	r11,PACA_EXSLB+EX_R11(r13)
	ld	r12,PACA_EXSLB+EX_R12(r13)
	ld	r13,PACA_EXSLB+EX_R13(r13)
	rfid
	b	.	/* prevent speculative execution */

2:	mfspr	r11,SPRN_SRR0
	ld	r10,PACAKBASE(r13)
	LOAD_HANDLER(r10,unrecov_slb)
	mtspr	SPRN_SRR0,r10
	ld	r10,PACAKMSR(r13)
	mtspr	SPRN_SRR1,r10
	rfid
	b	.

unrecov_slb:
	EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
	DISABLE_INTS
	bl	.save_nvgprs
1:	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.unrecoverable_exception
	b	1b


#ifdef CONFIG_PPC_970_NAP
power4_fixup_nap:
	andc	r9,r9,r10
	std	r9,TI_LOCAL_FLAGS(r11)
	ld	r10,_LINK(r1)		/* make idle task do the */
	std	r10,_NIP(r1)		/* equivalent of a blr */
	blr
#endif

	.align	7
	.globl alignment_common
alignment_common:
	mfspr	r10,SPRN_DAR
	std	r10,PACA_EXGEN+EX_DAR(r13)
	mfspr	r10,SPRN_DSISR
	stw	r10,PACA_EXGEN+EX_DSISR(r13)
	EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
	ld	r3,PACA_EXGEN+EX_DAR(r13)
	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)
	bl	.save_nvgprs
	DISABLE_INTS
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.alignment_exception
	b	.ret_from_except

	.align	7
	.globl program_check_common
program_check_common:
	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
	bl	.save_nvgprs
	DISABLE_INTS
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.program_check_exception
	b	.ret_from_except

	.align	7
	.globl fp_unavailable_common
fp_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
	bne	1f			/* if from user, just load it up */
	bl	.save_nvgprs
	DISABLE_INTS
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.kernel_fp_unavailable_exception
	BUG_OPCODE
1:	bl	.load_up_fpu
	b	fast_exception_return

	.align	7
	.globl altivec_unavailable_common
altivec_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
	beq	1f
	bl	.load_up_altivec
	b	fast_exception_return
1:
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif
	bl	.save_nvgprs
	DISABLE_INTS
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.altivec_unavailable_exception
	b	.ret_from_except

	.align	7
	.globl vsx_unavailable_common
vsx_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
#ifdef CONFIG_VSX
BEGIN_FTR_SECTION
	beq	1f
	b	.load_up_vsx
1:
END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif
	bl	.save_nvgprs
	DISABLE_INTS
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.vsx_unavailable_exception
	b	.ret_from_except

	.align	7
	.globl	__end_handlers
__end_handlers:

/*
 * Hash table stuff
 */
	.align	7
_STATIC(do_hash_page)
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)

	andis.	r0,r4,0xa410		/* weird error? */
	bne-	handle_page_fault	/* if not, try to insert a HPTE */
	andis.  r0,r4,DSISR_DABRMATCH@h
	bne-    handle_dabr_fault

BEGIN_FTR_SECTION
	andis.	r0,r4,0x0020		/* Is it a segment table fault? */
	bne-	do_ste_alloc		/* If so handle it */
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_SLB)

	CURRENT_THREAD_INFO(r11, r1)
	lwz	r0,TI_PREEMPT(r11)	/* If we're in an "NMI" */
	andis.	r0,r0,NMI_MASK@h	/* (i.e. an irq when soft-disabled) */
	bne	77f			/* then don't call hash_page now */
	/*
	 * We need to set the _PAGE_USER bit if MSR_PR is set or if we are
	 * accessing a userspace segment (even from the kernel). We assume
	 * kernel addresses always have the high bit set.
	 */
	rlwinm	r4,r4,32-25+9,31-9,31-9	/* DSISR_STORE -> _PAGE_RW */
	rotldi	r0,r3,15		/* Move high bit into MSR_PR posn */
	orc	r0,r12,r0		/* MSR_PR | ~high_bit */
	rlwimi	r4,r0,32-13,30,30	/* becomes _PAGE_USER access bit */
	ori	r4,r4,1			/* add _PAGE_PRESENT */
	rlwimi	r4,r5,22+2,31-2,31-2	/* Set _PAGE_EXEC if trap is 0x400 */

	/*
	 * r3 contains the faulting address
	 * r4 contains the required access permissions
	 * r5 contains the trap number
	 *
	 * at return r3 = 0 for success, 1 for page fault, negative for error
	 */
	bl	.hash_page		/* build HPTE if possible */
	cmpdi	r3,0			/* see if hash_page succeeded */

	/* Success */
	beq	fast_exc_return_irq	/* Return from exception on success */

	/* Error */
	blt-	13f

/* Here we have a page fault that hash_page can't handle. */
handle_page_fault:
11:	ld	r4,_DAR(r1)
	ld	r5,_DSISR(r1)
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	.do_page_fault
	cmpdi	r3,0
	beq+	12f
	bl	.save_nvgprs
	mr	r5,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	lwz	r4,_DAR(r1)
	bl	.bad_page_fault
	b	.ret_from_except

/* We have a data breakpoint exception - handle it */
handle_dabr_fault:
	bl	.save_nvgprs
	ld      r4,_DAR(r1)
	ld      r5,_DSISR(r1)
	addi    r3,r1,STACK_FRAME_OVERHEAD
	bl      .do_dabr
12:	b       .ret_from_except_lite


/* We have a page fault that hash_page could handle but HV refused
 * the PTE insertion
 */
13:	bl	.save_nvgprs
	mr	r5,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	ld	r4,_DAR(r1)
	bl	.low_hash_fault
	b	.ret_from_except

/*
 * We come here as a result of a DSI at a point where we don't want
 * to call hash_page, such as when we are accessing memory (possibly
 * user memory) inside a PMU interrupt that occurred while interrupts
 * were soft-disabled.  We want to invoke the exception handler for
 * the access, or panic if there isn't a handler.
 */
77:	bl	.save_nvgprs
	mr	r4,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	li	r5,SIGSEGV
	bl	.bad_page_fault
	b	.ret_from_except

	/* here we have a segment miss */
do_ste_alloc:
	bl	.ste_allocate		/* try to insert stab entry */
	cmpdi	r3,0
	bne-	handle_page_fault
	b	fast_exception_return

/*
 * r13 points to the PACA, r9 contains the saved CR,
 * r11 and r12 contain the saved SRR0 and SRR1.
 * r9 - r13 are saved in paca->exslb.
 * We assume we aren't going to take any exceptions during this procedure.
 * We assume (DAR >> 60) == 0xc.
 */
	.align	7
_GLOBAL(do_stab_bolted)
	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
	std	r11,PACA_EXSLB+EX_SRR0(r13)	/* save SRR0 in exc. frame */

	/* Hash to the primary group */
	ld	r10,PACASTABVIRT(r13)
	mfspr	r11,SPRN_DAR
	srdi	r11,r11,28
	rldimi	r10,r11,7,52	/* r10 = first ste of the group */

	/* Calculate VSID */
	/* This is a kernel address, so protovsid = ESID | 1 << 37 */
	li	r9,0x1
	rldimi  r11,r9,(CONTEXT_BITS + USER_ESID_BITS),0
	ASM_VSID_SCRAMBLE(r11, r9, 256M)
	rldic	r9,r11,12,16	/* r9 = vsid << 12 */

	/* Search the primary group for a free entry */
1:	ld	r11,0(r10)	/* Test valid bit of the current ste	*/
	andi.	r11,r11,0x80
	beq	2f
	addi	r10,r10,16
	andi.	r11,r10,0x70
	bne	1b

	/* Stick for only searching the primary group for now.		*/
	/* At least for now, we use a very simple random castout scheme */
	/* Use the TB as a random number ;  OR in 1 to avoid entry 0	*/
	mftb	r11
	rldic	r11,r11,4,57	/* r11 = (r11 << 4) & 0x70 */
	ori	r11,r11,0x10

	/* r10 currently points to an ste one past the group of interest */
	/* make it point to the randomly selected entry			*/
	subi	r10,r10,128
	or 	r10,r10,r11	/* r10 is the entry to invalidate	*/

	isync			/* mark the entry invalid		*/
	ld	r11,0(r10)
	rldicl	r11,r11,56,1	/* clear the valid bit */
	rotldi	r11,r11,8
	std	r11,0(r10)
	sync

	clrrdi	r11,r11,28	/* Get the esid part of the ste		*/
	slbie	r11

2:	std	r9,8(r10)	/* Store the vsid part of the ste	*/
	eieio

	mfspr	r11,SPRN_DAR		/* Get the new esid			*/
	clrrdi	r11,r11,28	/* Permits a full 32b of ESID		*/
	ori	r11,r11,0x90	/* Turn on valid and kp			*/
	std	r11,0(r10)	/* Put new entry back into the stab	*/

	sync

	/* All done -- return from exception. */
	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
	ld	r11,PACA_EXSLB+EX_SRR0(r13)	/* get saved SRR0 */

	andi.	r10,r12,MSR_RI
	beq-	unrecov_slb

	mtcrf	0x80,r9			/* restore CR */

	mfmsr	r10
	clrrdi	r10,r10,2
	mtmsrd	r10,1

	mtspr	SPRN_SRR0,r11
	mtspr	SPRN_SRR1,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)
	rfid
	b	.	/* prevent speculative execution */


	/* Equivalents to the above handlers for relocation-on interrupt vectors */
	STD_RELON_EXCEPTION_HV(., 0xe00, h_data_storage)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe00)
	STD_RELON_EXCEPTION_HV(., 0xe20, h_instr_storage)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe20)
	STD_RELON_EXCEPTION_HV(., 0xe40, emulation_assist)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe40)
	STD_RELON_EXCEPTION_HV(., 0xe60, hmi_exception)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe60)
	MASKABLE_RELON_EXCEPTION_HV(., 0xe80, h_doorbell)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe80)

	STD_RELON_EXCEPTION_PSERIES(., 0xf00, performance_monitor)
	STD_RELON_EXCEPTION_PSERIES(., 0xf20, altivec_unavailable)
	STD_RELON_EXCEPTION_PSERIES(., 0xf40, vsx_unavailable)

#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
/*
 * Data area reserved for FWNMI option.
 * This address (0x7000) is fixed by the RPA.
 */
	.= 0x7000
	.globl fwnmi_data_area
fwnmi_data_area:

	/* pseries and powernv need to keep the whole page from
	 * 0x7000 to 0x8000 free for use by the firmware
	 */
	. = 0x8000
#endif /* defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV) */

/* Space for CPU0's segment table */
	.balign 4096
	.globl initial_stab
initial_stab:
	.space	4096

#ifdef CONFIG_PPC_POWERNV
_GLOBAL(opal_mc_secondary_handler)
	HMT_MEDIUM
	SET_SCRATCH0(r13)
	GET_PACA(r13)
	clrldi	r3,r3,2
	tovirt(r3,r3)
	std	r3,PACA_OPAL_MC_EVT(r13)
	ld	r13,OPAL_MC_SRR0(r3)
	mtspr	SPRN_SRR0,r13
	ld	r13,OPAL_MC_SRR1(r3)
	mtspr	SPRN_SRR1,r13
	ld	r3,OPAL_MC_GPR3(r3)
	GET_SCRATCH0(r13)
	b	machine_check_pSeries
#endif /* CONFIG_PPC_POWERNV */