exceptions-64s.S 43.0 KB
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/*
 * This file contains the 64-bit "server" PowerPC variant
 * of the low level exception handling including exception
 * vectors, exception return, part of the slb and stab
 * handling and other fixed offset specific things.
 *
 * This file is meant to be #included from head_64.S due to
L
Lucas De Marchi 已提交
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 * position dependent assembly.
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 *
 * Most of this originates from head_64.S and thus has the same
 * copyright history.
 *
 */

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#include <asm/hw_irq.h>
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#include <asm/exception-64s.h>
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#include <asm/ptrace.h>
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#include <asm/cpuidle.h>
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/*
 * We layout physical memory as follows:
 * 0x0000 - 0x00ff : Secondary processor spin code
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 * 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
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 * 0x7000 - 0x7fff : FWNMI data area
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 * 0x8000 - 0x8fff : Initial (CPU0) segment table
 * 0x9000 -        : Early init and support code
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 */
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	/* Syscall routine is used twice, in reloc-off and reloc-on paths */
#define SYSCALL_PSERIES_1 					\
BEGIN_FTR_SECTION						\
	cmpdi	r0,0x1ebe ; 					\
	beq-	1f ;						\
END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)				\
	mr	r9,r13 ;					\
	GET_PACA(r13) ;						\
	mfspr	r11,SPRN_SRR0 ;					\
0:

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

#define SYSCALL_PSERIES_3					\
	/* Fast LE/BE switch system call */			\
1:	mfspr	r12,SPRN_SRR1 ;					\
	xori	r12,r12,MSR_LE ;				\
	mtspr	SPRN_SRR1,r12 ;					\
	rfid ;		/* return to userspace */		\
	b	. ;	/* prevent speculative execution */

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#if defined(CONFIG_RELOCATABLE)
	/*
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	 * We can't branch directly so we do it via the CTR which
	 * is volatile across system calls.
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	 */
#define SYSCALL_PSERIES_2_DIRECT				\
	mflr	r10 ;						\
	ld	r12,PACAKBASE(r13) ; 				\
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	LOAD_HANDLER(r12, system_call_entry) ;			\
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	mtctr	r12 ;						\
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	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 */			\
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	bctr ;
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#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) */	\
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	b	system_call_common ;
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#endif
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/*
 * 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:

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	.globl system_reset_pSeries;
system_reset_pSeries:
	SET_SCRATCH0(r13)
#ifdef CONFIG_PPC_P7_NAP
BEGIN_FTR_SECTION
	/* Running native on arch 2.06 or later, check if we are
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	 * waking up from nap/sleep/winkle.
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	 */
	mfspr	r13,SPRN_SRR1
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	rlwinm.	r13,r13,47-31,30,31
	beq	9f

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	cmpwi	cr3,r13,2

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	/*
	 * Check if last bit of HSPGR0 is set. This indicates whether we are
	 * waking up from winkle.
	 */
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	GET_PACA(r13)
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	clrldi	r5,r13,63
	clrrdi	r13,r13,1
	cmpwi	cr4,r5,1
	mtspr	SPRN_HSPRG0,r13

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	lbz	r0,PACA_THREAD_IDLE_STATE(r13)
	cmpwi   cr2,r0,PNV_THREAD_NAP
	bgt     cr2,8f				/* Either sleep or Winkle */

	/* Waking up from nap should not cause hypervisor state loss */
	bgt	cr3,.

	/* Waking up from nap */
	li	r0,PNV_THREAD_RUNNING
	stb	r0,PACA_THREAD_IDLE_STATE(r13)	/* Clear thread state */
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#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
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	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
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	b	kvm_start_guest
1:
#endif

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	/* Return SRR1 from power7_nap() */
	mfspr	r3,SPRN_SRR1
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	beq	cr3,2f
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	b	power7_wakeup_noloss
2:	b	power7_wakeup_loss
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	/* Fast Sleep wakeup on PowerNV */
8:	GET_PACA(r13)
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	b 	power7_wakeup_tb_loss
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9:
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END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
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#endif /* CONFIG_PPC_P7_NAP */
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	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
				 NOTEST, 0x100)
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	. = 0x200
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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
	 */
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	SET_SCRATCH0(r13)		/* save r13 */
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#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
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	OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
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	beq	9f

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	mfspr	r13,SPRN_SRR1
	rlwinm.	r13,r13,47-31,30,31
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	/* waking up from powersave (nap) state */
	cmpwi	cr1,r13,2
	/* Total loss of HV state is fatal. let's just stay stuck here */
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	OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
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	bgt	cr1,.
9:
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	OPT_SET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
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END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#endif /* CONFIG_PPC_P7_NAP */
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	EXCEPTION_PROLOG_0(PACA_EXMC)
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BEGIN_FTR_SECTION
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	b	machine_check_powernv_early
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FTR_SECTION_ELSE
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	b	machine_check_pSeries_0
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ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
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	. = 0x300
	.globl data_access_pSeries
data_access_pSeries:
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	SET_SCRATCH0(r13)
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	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common, EXC_STD,
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				 KVMTEST, 0x300)
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	. = 0x380
	.globl data_access_slb_pSeries
data_access_slb_pSeries:
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	SET_SCRATCH0(r13)
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	EXCEPTION_PROLOG_0(PACA_EXSLB)
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	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x380)
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	std	r3,PACA_EXSLB+EX_R3(r13)
	mfspr	r3,SPRN_DAR
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	mfspr	r12,SPRN_SRR1
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#ifndef CONFIG_RELOCATABLE
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	b	slb_miss_realmode
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#else
	/*
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	 * We can't just use a direct branch to slb_miss_realmode
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	 * because the distance from here to there depends on where
	 * the kernel ends up being put.
	 */
	mfctr	r11
	ld	r10,PACAKBASE(r13)
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	LOAD_HANDLER(r10, slb_miss_realmode)
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	mtctr	r10
	bctr
#endif

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	STD_EXCEPTION_PSERIES(0x400, instruction_access)
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	. = 0x480
	.globl instruction_access_slb_pSeries
instruction_access_slb_pSeries:
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	SET_SCRATCH0(r13)
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	EXCEPTION_PROLOG_0(PACA_EXSLB)
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	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x480)
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	std	r3,PACA_EXSLB+EX_R3(r13)
	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
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	mfspr	r12,SPRN_SRR1
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#ifndef CONFIG_RELOCATABLE
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	b	slb_miss_realmode
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#else
	mfctr	r11
	ld	r10,PACAKBASE(r13)
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	LOAD_HANDLER(r10, slb_miss_realmode)
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	mtctr	r10
	bctr
#endif

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	/* We open code these as we can't have a ". = x" (even with
	 * x = "." within a feature section
	 */
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	. = 0x500;
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	.globl hardware_interrupt_pSeries;
	.globl hardware_interrupt_hv;
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hardware_interrupt_pSeries:
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hardware_interrupt_hv:
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	BEGIN_FTR_SECTION
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		_MASKABLE_EXCEPTION_PSERIES(0x502, hardware_interrupt,
					    EXC_HV, SOFTEN_TEST_HV)
		KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x502)
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	FTR_SECTION_ELSE
		_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt,
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					    EXC_STD, SOFTEN_TEST_PR)
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		KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x500)
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	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
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	STD_EXCEPTION_PSERIES(0x600, alignment)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x600)
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	STD_EXCEPTION_PSERIES(0x700, program_check)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x700)
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	STD_EXCEPTION_PSERIES(0x800, fp_unavailable)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x800)
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	. = 0x900
	.globl decrementer_pSeries
decrementer_pSeries:
	_MASKABLE_EXCEPTION_PSERIES(0x900, decrementer, EXC_STD, SOFTEN_TEST_PR)

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	STD_EXCEPTION_HV(0x980, 0x982, hdecrementer)
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	MASKABLE_EXCEPTION_PSERIES(0xa00, 0xa00, doorbell_super)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xa00)
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	STD_EXCEPTION_PSERIES(0xb00, trap_0b)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xb00)
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	. = 0xc00
	.globl	system_call_pSeries
system_call_pSeries:
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	 /*
	  * If CONFIG_KVM_BOOK3S_64_HANDLER is set, save the PPR (on systems
	  * that support it) before changing to HMT_MEDIUM. That allows the KVM
	  * code to save that value into the guest state (it is the guest's PPR
	  * value). Otherwise just change to HMT_MEDIUM as userspace has
	  * already saved the PPR.
	  */
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#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
	SET_SCRATCH0(r13)
	GET_PACA(r13)
	std	r9,PACA_EXGEN+EX_R9(r13)
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	OPT_GET_SPR(r9, SPRN_PPR, CPU_FTR_HAS_PPR);
	HMT_MEDIUM;
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	std	r10,PACA_EXGEN+EX_R10(r13)
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	OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r9, CPU_FTR_HAS_PPR);
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	mfcr	r9
	KVMTEST(0xc00)
	GET_SCRATCH0(r13)
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#else
	HMT_MEDIUM;
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#endif
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	SYSCALL_PSERIES_1
	SYSCALL_PSERIES_2_RFID
	SYSCALL_PSERIES_3
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xc00)

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	STD_EXCEPTION_PSERIES(0xd00, single_step)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xd00)
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	/* At 0xe??? we have a bunch of hypervisor exceptions, we branch
	 * out of line to handle them
	 */
	. = 0xe00
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hv_data_storage_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	h_data_storage_hv
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	. = 0xe20
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hv_instr_storage_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	h_instr_storage_hv
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	. = 0xe40
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emulation_assist_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	emulation_assist_hv
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	. = 0xe60
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hv_exception_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	hmi_exception_early
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	. = 0xe80
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hv_doorbell_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	h_doorbell_hv
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	/* We need to deal with the Altivec unavailable exception
	 * here which is at 0xf20, thus in the middle of the
	 * prolog code of the PerformanceMonitor one. A little
	 * trickery is thus necessary
	 */
	. = 0xf00
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performance_monitor_pseries_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	performance_monitor_pSeries

	. = 0xf20
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altivec_unavailable_pseries_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	altivec_unavailable_pSeries

	. = 0xf40
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vsx_unavailable_pseries_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	vsx_unavailable_pSeries

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	. = 0xf60
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facility_unavailable_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	b	facility_unavailable_pSeries
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	. = 0xf80
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hv_facility_unavailable_trampoline:
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	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
	b	facility_unavailable_hv

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#ifdef CONFIG_CBE_RAS
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	STD_EXCEPTION_HV(0x1200, 0x1202, cbe_system_error)
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	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1202)
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#endif /* CONFIG_CBE_RAS */
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	STD_EXCEPTION_PSERIES(0x1300, instruction_breakpoint)
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	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x1300)
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	. = 0x1500
M
Michael Neuling 已提交
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	.global denorm_exception_hv
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denorm_exception_hv:
	mtspr	SPRN_SPRG_HSCRATCH0,r13
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	EXCEPTION_PROLOG_0(PACA_EXGEN)
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	EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0x1500)
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#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

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

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#ifdef CONFIG_CBE_RAS
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	STD_EXCEPTION_HV(0x1600, 0x1602, cbe_maintenance)
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	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1602)
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#endif /* CONFIG_CBE_RAS */
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	STD_EXCEPTION_PSERIES(0x1700, altivec_assist)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x1700)
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#ifdef CONFIG_CBE_RAS
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	STD_EXCEPTION_HV(0x1800, 0x1802, cbe_thermal)
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	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1802)
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#else
	. = 0x1800
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#endif /* CONFIG_CBE_RAS */


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

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	.align	7
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	/* moved from 0x200 */
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machine_check_powernv_early:
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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
	 *
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	 * 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
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	 *
	 * We use paca->in_mce to check whether this is the first entry or
	 * nested machine check. We increment paca->in_mce to track nested
	 * machine checks.
	 *
	 * If this is the first entry then set stack pointer to
	 * paca->mc_emergency_sp, otherwise r1 is already pointing to
	 * stack frame on mc_emergency stack.
	 *
	 * NOTE: We are here with MSR_ME=0 (off), which means we risk a
	 * checkstop if we get another machine check exception before we do
	 * rfid with MSR_ME=1.
	 */
	mr	r11,r1			/* Save r1 */
	lhz	r10,PACA_IN_MCE(r13)
	cmpwi	r10,0			/* Are we in nested machine check */
	bne	0f			/* Yes, we are. */
	/* First machine check entry */
	ld	r1,PACAMCEMERGSP(r13)	/* Use MC emergency stack */
0:	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame */
	addi	r10,r10,1		/* increment paca->in_mce */
	sth	r10,PACA_IN_MCE(r13)
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	/* Limit nested MCE to level 4 to avoid stack overflow */
	cmpwi	r10,4
	bgt	2f			/* Check if we hit limit of 4 */
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	std	r11,GPR1(r1)		/* Save r1 on the stack. */
	std	r11,0(r1)		/* make stack chain pointer */
	mfspr	r11,SPRN_SRR0		/* Save SRR0 */
	std	r11,_NIP(r1)
	mfspr	r11,SPRN_SRR1		/* Save SRR1 */
	std	r11,_MSR(r1)
	mfspr	r11,SPRN_DAR		/* Save DAR */
	std	r11,_DAR(r1)
	mfspr	r11,SPRN_DSISR		/* Save DSISR */
	std	r11,_DSISR(r1)
	std	r9,_CCR(r1)		/* Save CR in stackframe */
	/* Save r9 through r13 from EXMC save area to stack frame. */
	EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
	mfmsr	r11			/* get MSR value */
	ori	r11,r11,MSR_ME		/* turn on ME bit */
	ori	r11,r11,MSR_RI		/* turn on RI bit */
	ld	r12,PACAKBASE(r13)	/* get high part of &label */
	LOAD_HANDLER(r12, machine_check_handle_early)
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1:	mtspr	SPRN_SRR0,r12
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	mtspr	SPRN_SRR1,r11
	rfid
	b	.	/* prevent speculative execution */
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2:
	/* Stack overflow. Stay on emergency stack and panic.
	 * Keep the ME bit off while panic-ing, so that if we hit
	 * another machine check we checkstop.
	 */
	addi	r1,r1,INT_FRAME_SIZE	/* go back to previous stack frame */
	ld	r11,PACAKMSR(r13)
	ld	r12,PACAKBASE(r13)
	LOAD_HANDLER(r12, unrecover_mce)
	li	r10,MSR_ME
	andc	r11,r11,r10		/* Turn off MSR_ME */
	b	1b
	b	.	/* prevent speculative execution */
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END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)

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machine_check_pSeries:
	.globl machine_check_fwnmi
machine_check_fwnmi:
	SET_SCRATCH0(r13)		/* save r13 */
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	EXCEPTION_PROLOG_0(PACA_EXMC)
machine_check_pSeries_0:
	EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST, 0x200)
	EXCEPTION_PROLOG_PSERIES_1(machine_check_common, EXC_STD)
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	KVM_HANDLER_SKIP(PACA_EXMC, EXC_STD, 0x200)
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	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x300)
	KVM_HANDLER_SKIP(PACA_EXSLB, EXC_STD, 0x380)
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	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x400)
	KVM_HANDLER(PACA_EXSLB, EXC_STD, 0x480)
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x900)
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	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x982)

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#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
538 539 540 541 542 543 544 545

#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)

546 547 548 549 550 551 552 553 554
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
555 556 557 558 559 560 561 562

#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)

563
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
564 565 566 567 568 569 570 571 572 573

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:
574 575 576
	mtspr	SPRN_HSRR0,r11
	mtcrf	0x80,r9
	ld	r9,PACA_EXGEN+EX_R9(r13)
577
	RESTORE_PPR_PACA(PACA_EXGEN, r10)
578 579 580 581
BEGIN_FTR_SECTION
	ld	r10,PACA_EXGEN+EX_CFAR(r13)
	mtspr	SPRN_CFAR,r10
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
582 583 584 585 586 587 588 589
	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

590
	.align	7
591
	/* moved from 0xe00 */
592
	STD_EXCEPTION_HV_OOL(0xe02, h_data_storage)
593
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0xe02)
594
	STD_EXCEPTION_HV_OOL(0xe22, h_instr_storage)
595
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe22)
596
	STD_EXCEPTION_HV_OOL(0xe42, emulation_assist)
597
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe42)
598
	MASKABLE_EXCEPTION_HV_OOL(0xe62, hmi_exception)
599
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe62)
600

601
	MASKABLE_EXCEPTION_HV_OOL(0xe82, h_doorbell)
602
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe82)
603 604

	/* moved from 0xf00 */
605
	STD_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
606
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf00)
607
	STD_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
608
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf20)
609
	STD_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
610
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf40)
611
	STD_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
612
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf60)
613 614
	STD_EXCEPTION_HV_OOL(0xf82, facility_unavailable)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xf82)
615 616

/*
617 618 619 620
 * 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.
621 622
 * - If it was a HMI we return immediately since we handled it in realmode
 *   and it won't refire.
623 624
 * - else we hard disable and return.
 * This is called with r10 containing the value to OR to the paca field.
625
 */
626 627 628 629 630 631
#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);		\
632 633
	cmpwi	r10,PACA_IRQ_DEC;			\
	bne	1f;					\
634 635 636 637
	lis	r10,0x7fff;				\
	ori	r10,r10,0xffff;				\
	mtspr	SPRN_DEC,r10;				\
	b	2f;					\
638
1:	cmpwi	r10,PACA_IRQ_DBELL;			\
639 640
	beq	2f;					\
	cmpwi	r10,PACA_IRQ_HMI;			\
641 642
	beq	2f;					\
	mfspr	r10,SPRN_##_H##SRR1;			\
643 644 645 646 647 648 649 650 651
	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;					\
652
	b	.
653 654 655
	
	MASKED_INTERRUPT()
	MASKED_INTERRUPT(H)
656

657 658
/*
 * Called from arch_local_irq_enable when an interrupt needs
659 660
 * to be resent. r3 contains 0x500, 0x900, 0xa00 or 0xe80 to indicate
 * which kind of interrupt. MSR:EE is already off. We generate a
661 662 663 664 665 666 667 668 669 670 671 672 673 674 675
 * 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
676 677 678 679 680 681 682 683 684 685 686 687
	cmpwi	r3,0x900
	beq	decrementer_common
	cmpwi	r3,0x500
	beq	hardware_interrupt_common
BEGIN_FTR_SECTION
	cmpwi	r3,0xe80
	beq	h_doorbell_common
FTR_SECTION_ELSE
	cmpwi	r3,0xa00
	beq	doorbell_super_common
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
	blr
688

689 690 691 692 693 694 695
#ifdef CONFIG_PPC_PSERIES
/*
 * Vectors for the FWNMI option.  Share common code.
 */
	.globl system_reset_fwnmi
      .align 7
system_reset_fwnmi:
696
	SET_SCRATCH0(r13)		/* save r13 */
697 698
	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
				 NOTEST, 0x100)
699 700 701

#endif /* CONFIG_PPC_PSERIES */

702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
kvmppc_skip_interrupt:
	/*
	 * Here all GPRs are unchanged from when the interrupt happened
	 * except for r13, which is saved in SPRG_SCRATCH0.
	 */
	mfspr	r13, SPRN_SRR0
	addi	r13, r13, 4
	mtspr	SPRN_SRR0, r13
	GET_SCRATCH0(r13)
	rfid
	b	.

kvmppc_skip_Hinterrupt:
	/*
	 * Here all GPRs are unchanged from when the interrupt happened
	 * except for r13, which is saved in SPRG_SCRATCH0.
	 */
	mfspr	r13, SPRN_HSRR0
	addi	r13, r13, 4
	mtspr	SPRN_HSRR0, r13
	GET_SCRATCH0(r13)
	hrfid
	b	.
#endif

728
/*
729 730 731 732
 * 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.
733 734 735 736
 */

/*** Common interrupt handlers ***/

737
	STD_EXCEPTION_COMMON(0x100, system_reset, system_reset_exception)
738

739
	STD_EXCEPTION_COMMON_ASYNC(0x500, hardware_interrupt, do_IRQ)
740 741
	STD_EXCEPTION_COMMON_ASYNC(0x900, decrementer, timer_interrupt)
	STD_EXCEPTION_COMMON(0x980, hdecrementer, hdec_interrupt)
742
#ifdef CONFIG_PPC_DOORBELL
743
	STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, doorbell_exception)
744
#else
745
	STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, unknown_exception)
746
#endif
747 748 749 750
	STD_EXCEPTION_COMMON(0xb00, trap_0b, unknown_exception)
	STD_EXCEPTION_COMMON(0xd00, single_step, single_step_exception)
	STD_EXCEPTION_COMMON(0xe00, trap_0e, unknown_exception)
	STD_EXCEPTION_COMMON(0xe40, emulation_assist, emulation_assist_interrupt)
751
	STD_EXCEPTION_COMMON_ASYNC(0xe60, hmi_exception, handle_hmi_exception)
752
#ifdef CONFIG_PPC_DOORBELL
753
	STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, doorbell_exception)
754
#else
755
	STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, unknown_exception)
756
#endif
757 758 759
	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)
760
#ifdef CONFIG_ALTIVEC
761
	STD_EXCEPTION_COMMON(0x1700, altivec_assist, altivec_assist_exception)
762
#else
763
	STD_EXCEPTION_COMMON(0x1700, altivec_assist, unknown_exception)
764 765
#endif
#ifdef CONFIG_CBE_RAS
766 767 768
	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)
769 770
#endif /* CONFIG_CBE_RAS */

771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790
	/*
	 * Relocation-on interrupts: A subset of the interrupts can be delivered
	 * with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
	 * it.  Addresses are the same as the original interrupt addresses, but
	 * offset by 0xc000000000004000.
	 * It's impossible to receive interrupts below 0x300 via this mechanism.
	 * KVM: None of these traps are from the guest ; anything that escalated
	 * to HV=1 from HV=0 is delivered via real mode handlers.
	 */

	/*
	 * This uses the standard macro, since the original 0x300 vector
	 * only has extra guff for STAB-based processors -- which never
	 * come here.
	 */
	STD_RELON_EXCEPTION_PSERIES(0x4300, 0x300, data_access)
	. = 0x4380
	.globl data_access_slb_relon_pSeries
data_access_slb_relon_pSeries:
	SET_SCRATCH0(r13)
791
	EXCEPTION_PROLOG_0(PACA_EXSLB)
792 793 794 795 796
	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
797
	b	slb_miss_realmode
798 799
#else
	/*
800
	 * We can't just use a direct branch to slb_miss_realmode
801 802 803 804 805
	 * because the distance from here to there depends on where
	 * the kernel ends up being put.
	 */
	mfctr	r11
	ld	r10,PACAKBASE(r13)
806
	LOAD_HANDLER(r10, slb_miss_realmode)
807 808 809 810 811 812 813 814 815
	mtctr	r10
	bctr
#endif

	STD_RELON_EXCEPTION_PSERIES(0x4400, 0x400, instruction_access)
	. = 0x4480
	.globl instruction_access_slb_relon_pSeries
instruction_access_slb_relon_pSeries:
	SET_SCRATCH0(r13)
816
	EXCEPTION_PROLOG_0(PACA_EXSLB)
817 818 819 820 821
	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
822
	b	slb_miss_realmode
823 824 825
#else
	mfctr	r11
	ld	r10,PACAKBASE(r13)
826
	LOAD_HANDLER(r10, slb_miss_realmode)
827 828 829 830 831 832 833 834 835 836 837 838 839
	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)
840
	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
841 842 843 844 845
	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)
846
	MASKABLE_RELON_EXCEPTION_PSERIES(0x4a00, 0xa00, doorbell_super)
847 848 849 850 851 852 853 854 855 856 857 858 859
	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
860
	b	.	/* Can't happen, see v2.07 Book III-S section 6.5 */
861 862

	. = 0x4e20
863
	b	.	/* Can't happen, see v2.07 Book III-S section 6.5 */
864 865

	. = 0x4e40
866
emulation_assist_relon_trampoline:
867 868
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
869 870 871
	b	emulation_assist_relon_hv

	. = 0x4e60
872
	b	.	/* Can't happen, see v2.07 Book III-S section 6.5 */
873

874
	. = 0x4e80
875
h_doorbell_relon_trampoline:
876 877
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
878
	b	h_doorbell_relon_hv
879 880

	. = 0x4f00
881
performance_monitor_relon_pseries_trampoline:
882 883
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
884 885 886
	b	performance_monitor_relon_pSeries

	. = 0x4f20
887
altivec_unavailable_relon_pseries_trampoline:
888 889
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
890 891 892
	b	altivec_unavailable_relon_pSeries

	. = 0x4f40
893
vsx_unavailable_relon_pseries_trampoline:
894 895
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
896 897
	b	vsx_unavailable_relon_pSeries

898
	. = 0x4f60
899
facility_unavailable_relon_trampoline:
900 901
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
902
	b	facility_unavailable_relon_pSeries
903

904
	. = 0x4f80
905
hv_facility_unavailable_relon_trampoline:
906 907
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
908
	b	hv_facility_unavailable_relon_hv
909

910 911 912 913 914 915 916
	STD_RELON_EXCEPTION_PSERIES(0x5300, 0x1300, instruction_breakpoint)
#ifdef CONFIG_PPC_DENORMALISATION
	. = 0x5500
	b	denorm_exception_hv
#endif
	STD_RELON_EXCEPTION_PSERIES(0x5700, 0x1700, altivec_assist)

917 918 919 920
	.align	7
system_call_entry:
	b	system_call_common

921
ppc64_runlatch_on_trampoline:
922
	b	__ppc64_runlatch_on
923

924 925 926 927 928 929 930 931 932 933 934 935 936
/*
 * 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)
937
	RECONCILE_IRQ_STATE(r10, r11)
938
	ld	r12,_MSR(r1)
939 940 941
	ld	r3,PACA_EXGEN+EX_DAR(r13)
	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
	li	r5,0x300
942 943 944
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
945
	b	do_hash_page		/* Try to handle as hpte fault */
946 947 948
MMU_FTR_SECTION_ELSE
	b	handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_RADIX)
949

950
	.align  7
951
	.globl  h_data_storage_common
952
h_data_storage_common:
953 954 955 956 957
	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)
958
	bl      save_nvgprs
959
	RECONCILE_IRQ_STATE(r10, r11)
960
	addi    r3,r1,STACK_FRAME_OVERHEAD
961 962
	bl      unknown_exception
	b       ret_from_except
963

964 965 966 967
	.align	7
	.globl instruction_access_common
instruction_access_common:
	EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
968
	RECONCILE_IRQ_STATE(r10, r11)
969
	ld	r12,_MSR(r1)
970 971 972
	ld	r3,_NIP(r1)
	andis.	r4,r12,0x5820
	li	r5,0x400
973 974 975
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
976
	b	do_hash_page		/* Try to handle as hpte fault */
977 978 979
MMU_FTR_SECTION_ELSE
	b	handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_RADIX)
980

981
	STD_EXCEPTION_COMMON(0xe20, h_instr_storage, unknown_exception)
982

983 984 985 986 987 988 989 990 991 992 993 994 995 996
	/*
	 * Machine check is different because we use a different
	 * save area: PACA_EXMC instead of PACA_EXGEN.
	 */
	.align	7
	.globl machine_check_common
machine_check_common:

	mfspr	r10,SPRN_DAR
	std	r10,PACA_EXGEN+EX_DAR(r13)
	mfspr	r10,SPRN_DSISR
	stw	r10,PACA_EXGEN+EX_DSISR(r13)
	EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
	FINISH_NAP
997
	RECONCILE_IRQ_STATE(r10, r11)
998 999 1000 1001
	ld	r3,PACA_EXGEN+EX_DAR(r13)
	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)
1002
	bl	save_nvgprs
1003
	addi	r3,r1,STACK_FRAME_OVERHEAD
1004 1005
	bl	machine_check_exception
	b	ret_from_except
1006

1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018
	.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)
1019
	bl	save_nvgprs
1020
	RECONCILE_IRQ_STATE(r10, r11)
1021
	addi	r3,r1,STACK_FRAME_OVERHEAD
1022 1023
	bl	alignment_exception
	b	ret_from_except
1024 1025 1026 1027 1028

	.align	7
	.globl program_check_common
program_check_common:
	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
1029
	bl	save_nvgprs
1030
	RECONCILE_IRQ_STATE(r10, r11)
1031
	addi	r3,r1,STACK_FRAME_OVERHEAD
1032 1033
	bl	program_check_exception
	b	ret_from_except
1034 1035 1036 1037 1038 1039

	.align	7
	.globl fp_unavailable_common
fp_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
	bne	1f			/* if from user, just load it up */
1040
	bl	save_nvgprs
1041
	RECONCILE_IRQ_STATE(r10, r11)
1042
	addi	r3,r1,STACK_FRAME_OVERHEAD
1043
	bl	kernel_fp_unavailable_exception
1044
	BUG_OPCODE
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054
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
1055
	bl	load_up_fpu
1056
	b	fast_exception_return
1057 1058
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2:	/* User process was in a transaction */
1059
	bl	save_nvgprs
1060
	RECONCILE_IRQ_STATE(r10, r11)
1061
	addi	r3,r1,STACK_FRAME_OVERHEAD
1062 1063
	bl	fp_unavailable_tm
	b	ret_from_except
1064
#endif
1065 1066 1067 1068 1069 1070 1071
	.align	7
	.globl altivec_unavailable_common
altivec_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
	beq	1f
1072 1073 1074 1075 1076 1077 1078 1079 1080
#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
1081
	bl	load_up_altivec
1082
	b	fast_exception_return
1083 1084
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2:	/* User process was in a transaction */
1085
	bl	save_nvgprs
1086
	RECONCILE_IRQ_STATE(r10, r11)
1087
	addi	r3,r1,STACK_FRAME_OVERHEAD
1088 1089
	bl	altivec_unavailable_tm
	b	ret_from_except
1090
#endif
1091 1092 1093
1:
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif
1094
	bl	save_nvgprs
1095
	RECONCILE_IRQ_STATE(r10, r11)
1096
	addi	r3,r1,STACK_FRAME_OVERHEAD
1097 1098
	bl	altivec_unavailable_exception
	b	ret_from_except
1099 1100 1101 1102 1103 1104 1105

	.align	7
	.globl vsx_unavailable_common
vsx_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
#ifdef CONFIG_VSX
BEGIN_FTR_SECTION
1106
	beq	1f
1107 1108 1109 1110 1111 1112 1113 1114 1115
#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
1116
	b	load_up_vsx
1117 1118
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2:	/* User process was in a transaction */
1119
	bl	save_nvgprs
1120
	RECONCILE_IRQ_STATE(r10, r11)
1121
	addi	r3,r1,STACK_FRAME_OVERHEAD
1122 1123
	bl	vsx_unavailable_tm
	b	ret_from_except
1124
#endif
1125 1126 1127
1:
END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif
1128
	bl	save_nvgprs
1129
	RECONCILE_IRQ_STATE(r10, r11)
1130
	addi	r3,r1,STACK_FRAME_OVERHEAD
1131 1132
	bl	vsx_unavailable_exception
	b	ret_from_except
1133

1134 1135
	STD_EXCEPTION_COMMON(0xf60, facility_unavailable, facility_unavailable_exception)
	STD_EXCEPTION_COMMON(0xf80, hv_facility_unavailable, facility_unavailable_exception)
1136

1137
	/* Equivalents to the above handlers for relocation-on interrupt vectors */
1138 1139
	STD_RELON_EXCEPTION_HV_OOL(0xe40, emulation_assist)
	MASKABLE_RELON_EXCEPTION_HV_OOL(0xe80, h_doorbell)
1140

1141 1142 1143
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
1144
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
1145
	STD_RELON_EXCEPTION_HV_OOL(0xf80, hv_facility_unavailable)
1146

1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157
	/*
	 * 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:

1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172
#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) */

1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222
	.globl hmi_exception_early
hmi_exception_early:
	EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0xe60)
	mr	r10,r1			/* Save r1			*/
	ld	r1,PACAEMERGSP(r13)	/* Use emergency stack		*/
	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame		*/
	std	r9,_CCR(r1)		/* save CR in stackframe	*/
	mfspr	r11,SPRN_HSRR0		/* Save HSRR0 */
	std	r11,_NIP(r1)		/* save HSRR0 in stackframe	*/
	mfspr	r12,SPRN_HSRR1		/* Save SRR1 */
	std	r12,_MSR(r1)		/* save SRR1 in stackframe	*/
	std	r10,0(r1)		/* make stack chain pointer	*/
	std	r0,GPR0(r1)		/* save r0 in stackframe	*/
	std	r10,GPR1(r1)		/* save r1 in stackframe	*/
	EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
	EXCEPTION_PROLOG_COMMON_3(0xe60)
	addi	r3,r1,STACK_FRAME_OVERHEAD
	bl	hmi_exception_realmode
	/* Windup the stack. */
	/* Move original HSRR0 and HSRR1 into the respective regs */
	ld	r9,_MSR(r1)
	mtspr	SPRN_HSRR1,r9
	ld	r3,_NIP(r1)
	mtspr	SPRN_HSRR0,r3
	ld	r9,_CTR(r1)
	mtctr	r9
	ld	r9,_XER(r1)
	mtxer	r9
	ld	r9,_LINK(r1)
	mtlr	r9
	REST_GPR(0, r1)
	REST_8GPRS(2, r1)
	REST_GPR(10, r1)
	ld	r11,_CCR(r1)
	mtcr	r11
	REST_GPR(11, r1)
	REST_2GPRS(12, r1)
	/* restore original r1. */
	ld	r1,GPR1(r1)

	/*
	 * Go to virtual mode and pull the HMI event information from
	 * firmware.
	 */
	.globl hmi_exception_after_realmode
hmi_exception_after_realmode:
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
	b	hmi_exception_hv

1223

1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
#define MACHINE_CHECK_HANDLER_WINDUP			\
	/* Clear MSR_RI before setting SRR0 and SRR1. */\
	li	r0,MSR_RI;				\
	mfmsr	r9;		/* get MSR value */	\
	andc	r9,r9,r0;				\
	mtmsrd	r9,1;		/* Clear MSR_RI */	\
	/* Move original SRR0 and SRR1 into the respective regs */	\
	ld	r9,_MSR(r1);				\
	mtspr	SPRN_SRR1,r9;				\
	ld	r3,_NIP(r1);				\
	mtspr	SPRN_SRR0,r3;				\
	ld	r9,_CTR(r1);				\
	mtctr	r9;					\
	ld	r9,_XER(r1);				\
	mtxer	r9;					\
	ld	r9,_LINK(r1);				\
	mtlr	r9;					\
	REST_GPR(0, r1);				\
	REST_8GPRS(2, r1);				\
	REST_GPR(10, r1);				\
	ld	r11,_CCR(r1);				\
	mtcr	r11;					\
	/* Decrement paca->in_mce. */			\
	lhz	r12,PACA_IN_MCE(r13);			\
	subi	r12,r12,1;				\
	sth	r12,PACA_IN_MCE(r13);			\
	REST_GPR(11, r1);				\
	REST_2GPRS(12, r1);				\
	/* restore original r1. */			\
	ld	r1,GPR1(r1)

	/*
	 * Handle machine check early in real mode. We come here with
	 * ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
	 */
	.align	7
	.globl machine_check_handle_early
machine_check_handle_early:
	std	r0,GPR0(r1)	/* Save r0 */
	EXCEPTION_PROLOG_COMMON_3(0x200)
1264
	bl	save_nvgprs
1265
	addi	r3,r1,STACK_FRAME_OVERHEAD
1266
	bl	machine_check_early
1267
	std	r3,RESULT(r1)	/* Save result */
1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286
	ld	r12,_MSR(r1)
#ifdef	CONFIG_PPC_P7_NAP
	/*
	 * Check if thread was in power saving mode. We come here when any
	 * of the following is true:
	 * a. thread wasn't in power saving mode
	 * b. thread was in power saving mode with no state loss or
	 *    supervisor state loss
	 *
	 * Go back to nap again if (b) is true.
	 */
	rlwinm.	r11,r12,47-31,30,31	/* Was it in power saving mode? */
	beq	4f			/* No, it wasn;t */
	/* Thread was in power saving mode. Go back to nap again. */
	cmpwi	r11,2
	bne	3f
	/* Supervisor state loss */
	li	r0,1
	stb	r0,PACA_NAPSTATELOST(r13)
1287
3:	bl	machine_check_queue_event
1288 1289 1290
	MACHINE_CHECK_HANDLER_WINDUP
	GET_PACA(r13)
	ld	r1,PACAR1(r13)
1291
	li	r3,PNV_THREAD_NAP
1292
	b	power7_enter_nap_mode
1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304
4:
#endif
	/*
	 * Check if we are coming from hypervisor userspace. If yes then we
	 * continue in host kernel in V mode to deliver the MC event.
	 */
	rldicl.	r11,r12,4,63		/* See if MC hit while in HV mode. */
	beq	5f
	andi.	r11,r12,MSR_PR		/* See if coming from user. */
	bne	9f			/* continue in V mode if we are. */

5:
1305
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322
	/*
	 * 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
1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339
1:	mfspr	r11,SPRN_SRR0
	ld	r10,PACAKBASE(r13)
	LOAD_HANDLER(r10,unrecover_mce)
	mtspr	SPRN_SRR0,r10
	ld	r10,PACAKMSR(r13)
	/*
	 * We are going down. But there are chances that we might get hit by
	 * another MCE during panic path and we may run into unstable state
	 * with no way out. Hence, turn ME bit off while going down, so that
	 * when another MCE is hit during panic path, system will checkstop
	 * and hypervisor will get restarted cleanly by SP.
	 */
	li	r3,MSR_ME
	andc	r10,r10,r3		/* Turn off MSR_ME */
	mtspr	SPRN_SRR1,r10
	rfid
	b	.
1340
2:
1341 1342 1343 1344 1345 1346 1347 1348
	/*
	 * 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 */
1349 1350 1351 1352 1353
	/*
	 * Return from MC interrupt.
	 * Queue up the MCE event so that we can log it later, while
	 * returning from kernel or opal call.
	 */
1354
	bl	machine_check_queue_event
1355 1356 1357 1358 1359 1360 1361
	MACHINE_CHECK_HANDLER_WINDUP
	rfid
9:
	/* Deliver the machine check to host kernel in V mode. */
	MACHINE_CHECK_HANDLER_WINDUP
	b	machine_check_pSeries

1362 1363 1364
unrecover_mce:
	/* Invoke machine_check_exception to print MCE event and panic. */
	addi	r3,r1,STACK_FRAME_OVERHEAD
1365
	bl	machine_check_exception
1366 1367 1368 1369 1370
	/*
	 * 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
1371
	bl	unrecoverable_exception
1372
	b	1b
1373 1374 1375 1376 1377 1378 1379 1380
/*
 * 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.
 */
1381
slb_miss_realmode:
1382 1383 1384 1385 1386 1387 1388 1389
	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 */

1390 1391
#ifdef CONFIG_PPC_STD_MMU_64
BEGIN_MMU_FTR_SECTION
1392
	bl	slb_allocate_realmode
1393 1394
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_RADIX)
#endif
1395 1396 1397 1398 1399 1400 1401
	/* 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
1402 1403 1404
BEGIN_MMU_FTR_SECTION
	b	2f
END_MMU_FTR_SECTION_IFSET(MMU_FTR_RADIX)
1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433
	andi.	r10,r12,MSR_RI	/* check for unrecoverable exception */
	beq-	2f

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

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

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

unrecov_slb:
	EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
1434
	RECONCILE_IRQ_STATE(r10, r11)
1435
	bl	save_nvgprs
1436
1:	addi	r3,r1,STACK_FRAME_OVERHEAD
1437
	bl	unrecoverable_exception
1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449
	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

1450 1451 1452 1453
/*
 * Hash table stuff
 */
	.align	7
1454
do_hash_page:
1455
#ifdef CONFIG_PPC_STD_MMU_64
1456
	andis.	r0,r4,0xa410		/* weird error? */
1457
	bne-	handle_page_fault	/* if not, try to insert a HPTE */
1458 1459
	andis.  r0,r4,DSISR_DABRMATCH@h
	bne-    handle_dabr_fault
1460
	CURRENT_THREAD_INFO(r11, r1)
1461 1462 1463
	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 */
1464 1465 1466

	/*
	 * r3 contains the faulting address
1467
	 * r4 msr
1468
	 * r5 contains the trap number
1469
	 * r6 contains dsisr
1470
	 *
1471
	 * at return r3 = 0 for success, 1 for page fault, negative for error
1472
	 */
1473
        mr 	r4,r12
1474
	ld      r6,_DSISR(r1)
1475 1476
	bl	__hash_page		/* build HPTE if possible */
        cmpdi	r3,0			/* see if __hash_page succeeded */
1477

1478
	/* Success */
1479 1480
	beq	fast_exc_return_irq	/* Return from exception on success */

1481 1482
	/* Error */
	blt-	13f
1483
#endif /* CONFIG_PPC_STD_MMU_64 */
1484

1485 1486 1487 1488 1489
/* 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
1490
	bl	do_page_fault
1491
	cmpdi	r3,0
1492
	beq+	12f
1493
	bl	save_nvgprs
1494 1495 1496
	mr	r5,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	lwz	r4,_DAR(r1)
1497 1498
	bl	bad_page_fault
	b	ret_from_except
1499

1500 1501
/* We have a data breakpoint exception - handle it */
handle_dabr_fault:
1502
	bl	save_nvgprs
1503 1504 1505
	ld      r4,_DAR(r1)
	ld      r5,_DSISR(r1)
	addi    r3,r1,STACK_FRAME_OVERHEAD
1506 1507
	bl      do_break
12:	b       ret_from_except_lite
1508

1509

1510
#ifdef CONFIG_PPC_STD_MMU_64
1511 1512 1513
/* We have a page fault that hash_page could handle but HV refused
 * the PTE insertion
 */
1514
13:	bl	save_nvgprs
1515 1516 1517
	mr	r5,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	ld	r4,_DAR(r1)
1518 1519
	bl	low_hash_fault
	b	ret_from_except
1520
#endif
1521

1522 1523 1524 1525 1526 1527 1528
/*
 * 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.
 */
1529
77:	bl	save_nvgprs
1530 1531 1532
	mr	r4,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	li	r5,SIGSEGV
1533 1534
	bl	bad_page_fault
	b	ret_from_except
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/*
 * 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