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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	GET_PACA(r13)
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	bl	pnv_restore_hyp_resource
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	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
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#endif

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	/* Return SRR1 from power7_nap() */
	mfspr	r3,SPRN_SRR1
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	blt	cr3,2f
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	b	pnv_wakeup_loss
2:	b	pnv_wakeup_noloss
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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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	. = 0xea0
hv_virt_irq_trampoline:
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
	b	h_virt_irq_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
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#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)

532 533 534 535 536 537 538 539 540
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
541 542 543 544 545 546 547 548

#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)

549
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
550 551 552 553 554 555 556 557 558 559

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:
560 561 562
	mtspr	SPRN_HSRR0,r11
	mtcrf	0x80,r9
	ld	r9,PACA_EXGEN+EX_R9(r13)
563
	RESTORE_PPR_PACA(PACA_EXGEN, r10)
564 565 566 567
BEGIN_FTR_SECTION
	ld	r10,PACA_EXGEN+EX_CFAR(r13)
	mtspr	SPRN_CFAR,r10
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
568 569 570 571 572 573 574 575
	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

576
	.align	7
577
	/* moved from 0xe00 */
578
	STD_EXCEPTION_HV_OOL(0xe02, h_data_storage)
579
	KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0xe02)
580
	STD_EXCEPTION_HV_OOL(0xe22, h_instr_storage)
581
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe22)
582
	STD_EXCEPTION_HV_OOL(0xe42, emulation_assist)
583
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe42)
584
	MASKABLE_EXCEPTION_HV_OOL(0xe62, hmi_exception)
585
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe62)
586

587
	MASKABLE_EXCEPTION_HV_OOL(0xe82, h_doorbell)
588
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe82)
589

590 591 592
	MASKABLE_EXCEPTION_HV_OOL(0xea2, h_virt_irq)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xea2)

593
	/* moved from 0xf00 */
594
	STD_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
595
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf00)
596
	STD_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
597
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf20)
598
	STD_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
599
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf40)
600
	STD_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
601
	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xf60)
602 603
	STD_EXCEPTION_HV_OOL(0xf82, facility_unavailable)
	KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xf82)
604 605

/*
606 607 608 609
 * 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.
610 611
 * - If it was a HMI we return immediately since we handled it in realmode
 *   and it won't refire.
612 613
 * - else we hard disable and return.
 * This is called with r10 containing the value to OR to the paca field.
614
 */
615 616 617 618 619 620
#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);		\
621 622
	cmpwi	r10,PACA_IRQ_DEC;			\
	bne	1f;					\
623 624 625 626
	lis	r10,0x7fff;				\
	ori	r10,r10,0xffff;				\
	mtspr	SPRN_DEC,r10;				\
	b	2f;					\
627
1:	cmpwi	r10,PACA_IRQ_DBELL;			\
628 629
	beq	2f;					\
	cmpwi	r10,PACA_IRQ_HMI;			\
630 631
	beq	2f;					\
	mfspr	r10,SPRN_##_H##SRR1;			\
632 633 634 635 636 637 638 639 640
	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;					\
641
	b	.
642 643 644
	
	MASKED_INTERRUPT()
	MASKED_INTERRUPT(H)
645

646 647
/*
 * Called from arch_local_irq_enable when an interrupt needs
648 649
 * to be resent. r3 contains 0x500, 0x900, 0xa00 or 0xe80 to indicate
 * which kind of interrupt. MSR:EE is already off. We generate a
650 651 652 653 654 655 656 657 658 659 660 661 662 663 664
 * 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
665 666 667 668 669 670 671
	cmpwi	r3,0x900
	beq	decrementer_common
	cmpwi	r3,0x500
	beq	hardware_interrupt_common
BEGIN_FTR_SECTION
	cmpwi	r3,0xe80
	beq	h_doorbell_common
672 673
	cmpwi	r3,0xea0
	beq	h_virt_irq_common
674 675 676 677 678
FTR_SECTION_ELSE
	cmpwi	r3,0xa00
	beq	doorbell_super_common
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
	blr
679

680 681 682 683 684 685 686
#ifdef CONFIG_PPC_PSERIES
/*
 * Vectors for the FWNMI option.  Share common code.
 */
	.globl system_reset_fwnmi
      .align 7
system_reset_fwnmi:
687
	SET_SCRATCH0(r13)		/* save r13 */
688 689
	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
				 NOTEST, 0x100)
690 691 692

#endif /* CONFIG_PPC_PSERIES */

693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718
#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

719
/*
720 721 722 723
 * 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.
724 725 726 727
 */

/*** Common interrupt handlers ***/

728
	STD_EXCEPTION_COMMON(0x100, system_reset, system_reset_exception)
729

730
	STD_EXCEPTION_COMMON_ASYNC(0x500, hardware_interrupt, do_IRQ)
731 732
	STD_EXCEPTION_COMMON_ASYNC(0x900, decrementer, timer_interrupt)
	STD_EXCEPTION_COMMON(0x980, hdecrementer, hdec_interrupt)
733
#ifdef CONFIG_PPC_DOORBELL
734
	STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, doorbell_exception)
735
#else
736
	STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, unknown_exception)
737
#endif
738 739 740 741
	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)
742
	STD_EXCEPTION_COMMON_ASYNC(0xe60, hmi_exception, handle_hmi_exception)
743
#ifdef CONFIG_PPC_DOORBELL
744
	STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, doorbell_exception)
745
#else
746
	STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, unknown_exception)
747
#endif
748
	STD_EXCEPTION_COMMON_ASYNC(0xea0, h_virt_irq, do_IRQ)
749 750 751
	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)
752
#ifdef CONFIG_ALTIVEC
753
	STD_EXCEPTION_COMMON(0x1700, altivec_assist, altivec_assist_exception)
754
#else
755
	STD_EXCEPTION_COMMON(0x1700, altivec_assist, unknown_exception)
756 757
#endif

758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777
	/*
	 * 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)
778
	EXCEPTION_PROLOG_0(PACA_EXSLB)
779 780 781 782 783
	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
784
	b	slb_miss_realmode
785 786
#else
	/*
787
	 * We can't just use a direct branch to slb_miss_realmode
788 789 790 791 792
	 * because the distance from here to there depends on where
	 * the kernel ends up being put.
	 */
	mfctr	r11
	ld	r10,PACAKBASE(r13)
793
	LOAD_HANDLER(r10, slb_miss_realmode)
794 795 796 797 798 799 800 801 802
	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)
803
	EXCEPTION_PROLOG_0(PACA_EXSLB)
804 805 806 807 808
	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
809
	b	slb_miss_realmode
810 811 812
#else
	mfctr	r11
	ld	r10,PACAKBASE(r13)
813
	LOAD_HANDLER(r10, slb_miss_realmode)
814 815 816 817 818 819 820 821 822 823 824 825 826
	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)
827
	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
828 829 830 831 832
	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)
833
	MASKABLE_RELON_EXCEPTION_PSERIES(0x4a00, 0xa00, doorbell_super)
834 835 836 837 838 839 840 841 842 843 844 845 846
	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
847
	b	.	/* Can't happen, see v2.07 Book III-S section 6.5 */
848 849

	. = 0x4e20
850
	b	.	/* Can't happen, see v2.07 Book III-S section 6.5 */
851 852

	. = 0x4e40
853
emulation_assist_relon_trampoline:
854 855
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
856 857 858
	b	emulation_assist_relon_hv

	. = 0x4e60
859
	b	.	/* Can't happen, see v2.07 Book III-S section 6.5 */
860

861
	. = 0x4e80
862
h_doorbell_relon_trampoline:
863 864
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
865
	b	h_doorbell_relon_hv
866

867 868 869 870 871 872
	. = 0x4ea0
h_virt_irq_relon_trampoline:
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
	b	h_virt_irq_relon_hv

873
	. = 0x4f00
874
performance_monitor_relon_pseries_trampoline:
875 876
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
877 878 879
	b	performance_monitor_relon_pSeries

	. = 0x4f20
880
altivec_unavailable_relon_pseries_trampoline:
881 882
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
883 884 885
	b	altivec_unavailable_relon_pSeries

	. = 0x4f40
886
vsx_unavailable_relon_pseries_trampoline:
887 888
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
889 890
	b	vsx_unavailable_relon_pSeries

891
	. = 0x4f60
892
facility_unavailable_relon_trampoline:
893 894
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
895
	b	facility_unavailable_relon_pSeries
896

897
	. = 0x4f80
898
hv_facility_unavailable_relon_trampoline:
899 900
	SET_SCRATCH0(r13)
	EXCEPTION_PROLOG_0(PACA_EXGEN)
901
	b	hv_facility_unavailable_relon_hv
902

903 904 905 906 907 908 909
	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)

910 911 912 913
	.align	7
system_call_entry:
	b	system_call_common

914
ppc64_runlatch_on_trampoline:
915
	b	__ppc64_runlatch_on
916

917 918 919 920 921 922 923 924 925 926 927 928 929
/*
 * 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)
930
	RECONCILE_IRQ_STATE(r10, r11)
931
	ld	r12,_MSR(r1)
932 933 934
	ld	r3,PACA_EXGEN+EX_DAR(r13)
	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
	li	r5,0x300
935 936 937
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
938
	b	do_hash_page		/* Try to handle as hpte fault */
939 940 941
MMU_FTR_SECTION_ELSE
	b	handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_RADIX)
942

943
	.align  7
944
	.globl  h_data_storage_common
945
h_data_storage_common:
946 947 948 949 950
	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)
951
	bl      save_nvgprs
952
	RECONCILE_IRQ_STATE(r10, r11)
953
	addi    r3,r1,STACK_FRAME_OVERHEAD
954 955
	bl      unknown_exception
	b       ret_from_except
956

957 958 959 960
	.align	7
	.globl instruction_access_common
instruction_access_common:
	EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
961
	RECONCILE_IRQ_STATE(r10, r11)
962
	ld	r12,_MSR(r1)
963 964 965
	ld	r3,_NIP(r1)
	andis.	r4,r12,0x5820
	li	r5,0x400
966 967 968
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)
BEGIN_MMU_FTR_SECTION
969
	b	do_hash_page		/* Try to handle as hpte fault */
970 971 972
MMU_FTR_SECTION_ELSE
	b	handle_page_fault
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_RADIX)
973

974
	STD_EXCEPTION_COMMON(0xe20, h_instr_storage, unknown_exception)
975

976 977 978 979 980 981 982 983 984 985 986 987 988 989
	/*
	 * 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
990
	RECONCILE_IRQ_STATE(r10, r11)
991 992 993 994
	ld	r3,PACA_EXGEN+EX_DAR(r13)
	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
	std	r3,_DAR(r1)
	std	r4,_DSISR(r1)
995
	bl	save_nvgprs
996
	addi	r3,r1,STACK_FRAME_OVERHEAD
997 998
	bl	machine_check_exception
	b	ret_from_except
999

1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011
	.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)
1012
	bl	save_nvgprs
1013
	RECONCILE_IRQ_STATE(r10, r11)
1014
	addi	r3,r1,STACK_FRAME_OVERHEAD
1015 1016
	bl	alignment_exception
	b	ret_from_except
1017 1018 1019 1020 1021

	.align	7
	.globl program_check_common
program_check_common:
	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
1022
	bl	save_nvgprs
1023
	RECONCILE_IRQ_STATE(r10, r11)
1024
	addi	r3,r1,STACK_FRAME_OVERHEAD
1025 1026
	bl	program_check_exception
	b	ret_from_except
1027 1028 1029 1030 1031 1032

	.align	7
	.globl fp_unavailable_common
fp_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
	bne	1f			/* if from user, just load it up */
1033
	bl	save_nvgprs
1034
	RECONCILE_IRQ_STATE(r10, r11)
1035
	addi	r3,r1,STACK_FRAME_OVERHEAD
1036
	bl	kernel_fp_unavailable_exception
1037
	BUG_OPCODE
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047
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
1048
	bl	load_up_fpu
1049
	b	fast_exception_return
1050 1051
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2:	/* User process was in a transaction */
1052
	bl	save_nvgprs
1053
	RECONCILE_IRQ_STATE(r10, r11)
1054
	addi	r3,r1,STACK_FRAME_OVERHEAD
1055 1056
	bl	fp_unavailable_tm
	b	ret_from_except
1057
#endif
1058 1059 1060 1061 1062 1063 1064
	.align	7
	.globl altivec_unavailable_common
altivec_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
	beq	1f
1065 1066 1067 1068 1069 1070 1071 1072 1073
#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
1074
	bl	load_up_altivec
1075
	b	fast_exception_return
1076 1077
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2:	/* User process was in a transaction */
1078
	bl	save_nvgprs
1079
	RECONCILE_IRQ_STATE(r10, r11)
1080
	addi	r3,r1,STACK_FRAME_OVERHEAD
1081 1082
	bl	altivec_unavailable_tm
	b	ret_from_except
1083
#endif
1084 1085 1086
1:
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif
1087
	bl	save_nvgprs
1088
	RECONCILE_IRQ_STATE(r10, r11)
1089
	addi	r3,r1,STACK_FRAME_OVERHEAD
1090 1091
	bl	altivec_unavailable_exception
	b	ret_from_except
1092 1093 1094 1095 1096 1097 1098

	.align	7
	.globl vsx_unavailable_common
vsx_unavailable_common:
	EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
#ifdef CONFIG_VSX
BEGIN_FTR_SECTION
1099
	beq	1f
1100 1101 1102 1103 1104 1105 1106 1107 1108
#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
1109
	b	load_up_vsx
1110 1111
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2:	/* User process was in a transaction */
1112
	bl	save_nvgprs
1113
	RECONCILE_IRQ_STATE(r10, r11)
1114
	addi	r3,r1,STACK_FRAME_OVERHEAD
1115 1116
	bl	vsx_unavailable_tm
	b	ret_from_except
1117
#endif
1118 1119 1120
1:
END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif
1121
	bl	save_nvgprs
1122
	RECONCILE_IRQ_STATE(r10, r11)
1123
	addi	r3,r1,STACK_FRAME_OVERHEAD
1124 1125
	bl	vsx_unavailable_exception
	b	ret_from_except
1126

1127
	/* Equivalents to the above handlers for relocation-on interrupt vectors */
1128 1129
	STD_RELON_EXCEPTION_HV_OOL(0xe40, emulation_assist)
	MASKABLE_RELON_EXCEPTION_HV_OOL(0xe80, h_doorbell)
1130
	MASKABLE_RELON_EXCEPTION_HV_OOL(0xea0, h_virt_irq)
1131

1132 1133 1134
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
1135
	STD_RELON_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
1136
	STD_RELON_EXCEPTION_HV_OOL(0xf80, hv_facility_unavailable)
1137

1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148
	/*
	 * 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:

1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163
#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) */

1164 1165 1166 1167 1168 1169 1170 1171 1172
	STD_EXCEPTION_COMMON(0xf60, facility_unavailable, facility_unavailable_exception)
	STD_EXCEPTION_COMMON(0xf80, hv_facility_unavailable, facility_unavailable_exception)

#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 */

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	pnv_enter_arch207_idle_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 1402
	/* 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 */
1403
BEGIN_MMU_FTR_SECTION
1404
	beq-	2f
1405 1406 1407
FTR_SECTION_ELSE
	b	2f
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_RADIX)
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 1434

.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)
1435
	RECONCILE_IRQ_STATE(r10, r11)
1436
	bl	save_nvgprs
1437
1:	addi	r3,r1,STACK_FRAME_OVERHEAD
1438
	bl	unrecoverable_exception
1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450
	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

1451 1452 1453 1454
/*
 * Hash table stuff
 */
	.align	7
1455
do_hash_page:
1456
#ifdef CONFIG_PPC_STD_MMU_64
1457
	andis.	r0,r4,0xa410		/* weird error? */
1458
	bne-	handle_page_fault	/* if not, try to insert a HPTE */
1459 1460
	andis.  r0,r4,DSISR_DABRMATCH@h
	bne-    handle_dabr_fault
1461
	CURRENT_THREAD_INFO(r11, r1)
1462 1463 1464
	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 */
1465 1466 1467

	/*
	 * r3 contains the faulting address
1468
	 * r4 msr
1469
	 * r5 contains the trap number
1470
	 * r6 contains dsisr
1471
	 *
1472
	 * at return r3 = 0 for success, 1 for page fault, negative for error
1473
	 */
1474
        mr 	r4,r12
1475
	ld      r6,_DSISR(r1)
1476 1477
	bl	__hash_page		/* build HPTE if possible */
        cmpdi	r3,0			/* see if __hash_page succeeded */
1478

1479
	/* Success */
1480 1481
	beq	fast_exc_return_irq	/* Return from exception on success */

1482 1483
	/* Error */
	blt-	13f
1484
#endif /* CONFIG_PPC_STD_MMU_64 */
1485

1486 1487 1488 1489 1490
/* 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
1491
	bl	do_page_fault
1492
	cmpdi	r3,0
1493
	beq+	12f
1494
	bl	save_nvgprs
1495 1496 1497
	mr	r5,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	lwz	r4,_DAR(r1)
1498 1499
	bl	bad_page_fault
	b	ret_from_except
1500

1501 1502
/* We have a data breakpoint exception - handle it */
handle_dabr_fault:
1503
	bl	save_nvgprs
1504 1505 1506
	ld      r4,_DAR(r1)
	ld      r5,_DSISR(r1)
	addi    r3,r1,STACK_FRAME_OVERHEAD
1507 1508
	bl      do_break
12:	b       ret_from_except_lite
1509

1510

1511
#ifdef CONFIG_PPC_STD_MMU_64
1512 1513 1514
/* We have a page fault that hash_page could handle but HV refused
 * the PTE insertion
 */
1515
13:	bl	save_nvgprs
1516 1517 1518
	mr	r5,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	ld	r4,_DAR(r1)
1519 1520
	bl	low_hash_fault
	b	ret_from_except
1521
#endif
1522

1523 1524 1525 1526 1527 1528 1529
/*
 * 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.
 */
1530
77:	bl	save_nvgprs
1531 1532 1533
	mr	r4,r3
	addi	r3,r1,STACK_FRAME_OVERHEAD
	li	r5,SIGSEGV
1534 1535
	bl	bad_page_fault
	b	ret_from_except
1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595

/*
 * 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