Commit 8729c26e authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Michael Ellerman
Browse files

powerpc/64s/exception: Move real to virt switch into the common handler 



The real mode interrupt entry points currently use rfid to branch to
the common handler in virtual mode. This is a significant amount of
code, and forces other code (notably the KVM test) to live in the
real mode handler.

In the interest of minimising the amount of code that runs unrelocated
move the switch to virt mode into the common code, and do it with
mtmsrd, which avoids clobbering SRRs (although the post-KVMTEST
performance of real-mode interrupt handlers is not a big concern these
days).

This requires CTR to always be saved (real-mode needs to reach 0xc...)
but that's not a huge impact these days. It could be optimized away in
future.

mpe: Incorporate fix from Nick:

It's possible for interrupts to be replayed when TM is enabled and
suspended, for example rt_sigreturn, where the mtmsrd MSR_KERNEL in
the real-mode entry point to the common handler causes a TM Bad Thing
exception (due to attempting to clear suspended).

The fix for this is to have replay interrupts go to the _virt entry
point and skip the mtmsrd, which matches what happens before this
patch.

Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-11-npiggin@gmail.com
parent a3cd35be

arch/powerpc/include/asm/exception-64s.h

+0 −4
Original line number Diff line number Diff line
@@ -33,11 +33,7 @@ 
#include <asm/feature-fixups.h>



/* PACA save area size in u64 units (exgen, exmc, etc) */

#if defined(CONFIG_RELOCATABLE)

#define EX_SIZE		10

#else

#define EX_SIZE		9

#endif



/*

 * maximum recursive depth of MCE exceptions

arch/powerpc/kernel/exceptions-64s.S

+116 −149
Original line number Diff line number Diff line
@@ -32,16 +32,10 @@ 
#define EX_CCR		52

#define EX_CFAR		56

#define EX_PPR		64

#if defined(CONFIG_RELOCATABLE)

#define EX_CTR		72

.if EX_SIZE != 10

	.error "EX_SIZE is wrong"

.endif

#else

.if EX_SIZE != 9

	.error "EX_SIZE is wrong"

.endif

#endif



/*

 * Following are fixed section helper macros.
@@ -124,22 +118,6 @@ name: 
#define EXC_HV		1

#define EXC_STD		0



#if defined(CONFIG_RELOCATABLE)

/*

 * If we support interrupts with relocation on AND we're a relocatable kernel,

 * we need to use CTR to get to the 2nd level handler.  So, save/restore it

 * when required.

 */

#define SAVE_CTR(reg, area)	mfctr	reg ; 	std	reg,area+EX_CTR(r13)

#define GET_CTR(reg, area) 			ld	reg,area+EX_CTR(r13)

#define RESTORE_CTR(reg, area)	ld	reg,area+EX_CTR(r13) ; mtctr reg

#else

/* ...else CTR is unused and in register. */

#define SAVE_CTR(reg, area)

#define GET_CTR(reg, area) 	mfctr	reg

#define RESTORE_CTR(reg, area)

#endif



/*

 * PPR save/restore macros used in exceptions-64s.S

 * Used for P7 or later processors
@@ -199,6 +177,7 @@ END_FTR_SECTION_NESTED(ftr,ftr,943) 
#define IVEC		.L_IVEC_\name\()

#define IHSRR		.L_IHSRR_\name\()

#define IAREA		.L_IAREA_\name\()

#define IVIRT		.L_IVIRT_\name\()

#define IISIDE		.L_IISIDE_\name\()

#define IDAR		.L_IDAR_\name\()

#define IDSISR		.L_IDSISR_\name\()
@@ -232,6 +211,9 @@ do_define_int n 
	.ifndef IAREA

		IAREA=PACA_EXGEN

	.endif

	.ifndef IVIRT

		IVIRT=1

	.endif

	.ifndef IISIDE

		IISIDE=0

	.endif
@@ -325,7 +307,7 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) 
	 * outside the head section. CONFIG_RELOCATABLE KVM expects CTR

	 * to be saved in HSTATE_SCRATCH1.

	 */

	mfctr	r9

	ld	r9,IAREA+EX_CTR(r13)

	std	r9,HSTATE_SCRATCH1(r13)

	__LOAD_FAR_HANDLER(r9, kvmppc_interrupt)

	mtctr	r9
@@ -362,101 +344,6 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) 
.endm

#endif



.macro INT_SAVE_SRR_AND_JUMP label, hsrr, set_ri

	ld	r10,PACAKMSR(r13)	/* get MSR value for kernel */

	.if ! \set_ri

	xori	r10,r10,MSR_RI		/* Clear MSR_RI */

	.endif

	.if \hsrr == EXC_HV_OR_STD

	BEGIN_FTR_SECTION

	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */

	mfspr	r12,SPRN_HSRR1		/* and HSRR1 */

	mtspr	SPRN_HSRR1,r10

	FTR_SECTION_ELSE

	mfspr	r11,SPRN_SRR0		/* save SRR0 */

	mfspr	r12,SPRN_SRR1		/* and SRR1 */

	mtspr	SPRN_SRR1,r10

	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

	.elseif \hsrr

	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */

	mfspr	r12,SPRN_HSRR1		/* and HSRR1 */

	mtspr	SPRN_HSRR1,r10

	.else

	mfspr	r11,SPRN_SRR0		/* save SRR0 */

	mfspr	r12,SPRN_SRR1		/* and SRR1 */

	mtspr	SPRN_SRR1,r10

	.endif

	LOAD_HANDLER(r10, \label\())

	.if \hsrr == EXC_HV_OR_STD

	BEGIN_FTR_SECTION

	mtspr	SPRN_HSRR0,r10

	HRFI_TO_KERNEL

	FTR_SECTION_ELSE

	mtspr	SPRN_SRR0,r10

	RFI_TO_KERNEL

	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

	.elseif \hsrr

	mtspr	SPRN_HSRR0,r10

	HRFI_TO_KERNEL

	.else

	mtspr	SPRN_SRR0,r10

	RFI_TO_KERNEL

	.endif

	b	.	/* prevent speculative execution */

.endm



/* INT_SAVE_SRR_AND_JUMP works for real or virt, this is faster but virt only */

.macro INT_VIRT_SAVE_SRR_AND_JUMP label, hsrr

#ifdef CONFIG_RELOCATABLE

	.if \hsrr == EXC_HV_OR_STD

	BEGIN_FTR_SECTION

	mfspr	r11,SPRN_HSRR0	/* save HSRR0 */

	FTR_SECTION_ELSE

	mfspr	r11,SPRN_SRR0	/* save SRR0 */

	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

	.elseif \hsrr

	mfspr	r11,SPRN_HSRR0	/* save HSRR0 */

	.else

	mfspr	r11,SPRN_SRR0	/* save SRR0 */

	.endif

	LOAD_HANDLER(r12, \label\())

	mtctr	r12

	.if \hsrr == EXC_HV_OR_STD

	BEGIN_FTR_SECTION

	mfspr	r12,SPRN_HSRR1	/* and HSRR1 */

	FTR_SECTION_ELSE

	mfspr	r12,SPRN_SRR1	/* and HSRR1 */

	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

	.elseif \hsrr

	mfspr	r12,SPRN_HSRR1	/* and HSRR1 */

	.else

	mfspr	r12,SPRN_SRR1	/* and HSRR1 */

	.endif

	li	r10,MSR_RI

	mtmsrd 	r10,1		/* Set RI (EE=0) */

	bctr

#else

	.if \hsrr == EXC_HV_OR_STD

	BEGIN_FTR_SECTION

	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */

	mfspr	r12,SPRN_HSRR1		/* and HSRR1 */

	FTR_SECTION_ELSE

	mfspr	r11,SPRN_SRR0		/* save SRR0 */

	mfspr	r12,SPRN_SRR1		/* and SRR1 */

	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

	.elseif \hsrr

	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */

	mfspr	r12,SPRN_HSRR1		/* and HSRR1 */

	.else

	mfspr	r11,SPRN_SRR0		/* save SRR0 */

	mfspr	r12,SPRN_SRR1		/* and SRR1 */

	.endif

	li	r10,MSR_RI

	mtmsrd 	r10,1			/* Set RI (EE=0) */

	b	\label

#endif

.endm



/*

 * This is the BOOK3S interrupt entry code macro.

 *
@@ -477,6 +364,23 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) 
 * - Fall through and continue executing in real, unrelocated mode.

 *   This is done if early=2.

 */



.macro GEN_BRANCH_TO_COMMON name, virt

	.if \virt

#ifndef CONFIG_RELOCATABLE

	b	\name\()_common_virt

#else

	LOAD_HANDLER(r10, \name\()_common_virt)

	mtctr	r10

	bctr

#endif

	.else

	LOAD_HANDLER(r10, \name\()_common_real)

	mtctr	r10

	bctr

	.endif

.endm



.macro GEN_INT_ENTRY name, virt, ool=0

	SET_SCRATCH0(r13)			/* save r13 */

	GET_PACA(r13)
@@ -500,8 +404,10 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) 
	OPT_SAVE_REG_TO_PACA(IAREA+EX_PPR, r9, CPU_FTR_HAS_PPR)

	OPT_SAVE_REG_TO_PACA(IAREA+EX_CFAR, r10, CPU_FTR_CFAR)

	INTERRUPT_TO_KERNEL

	SAVE_CTR(r10, IAREA)

	mfctr	r10

	std	r10,IAREA+EX_CTR(r13)

	mfcr	r9



	.if (!\virt && IKVM_REAL) || (\virt && IKVM_VIRT)

		KVMTEST \name IHSRR IVEC

	.endif
@@ -566,27 +472,58 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) 
	.if IEARLY == 2

	/* nothing more */

	.elseif IEARLY

	mfctr	r10			/* save ctr, even for !RELOCATABLE */

	BRANCH_TO_C000(r11, \name\()_common)

	.elseif !\virt

	INT_SAVE_SRR_AND_JUMP \name\()_common, IHSRR, ISET_RI

	.else

	INT_VIRT_SAVE_SRR_AND_JUMP \name\()_common, IHSRR

	.if IHSRR == EXC_HV_OR_STD

	BEGIN_FTR_SECTION

	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */

	mfspr	r12,SPRN_HSRR1		/* and HSRR1 */

	FTR_SECTION_ELSE

	mfspr	r11,SPRN_SRR0		/* save SRR0 */

	mfspr	r12,SPRN_SRR1		/* and SRR1 */

	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

	.elseif IHSRR

	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */

	mfspr	r12,SPRN_HSRR1		/* and HSRR1 */

	.else

	mfspr	r11,SPRN_SRR0		/* save SRR0 */

	mfspr	r12,SPRN_SRR1		/* and SRR1 */

	.endif

	GEN_BRANCH_TO_COMMON \name \virt

	.endif



	.if \ool

	.popsection

	.endif

.endm



/*

 * On entry r13 points to the paca, r9-r13 are saved in the paca,

 * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and

 * SRR1, and relocation is on.

 *

 * If stack=0, then the stack is already set in r1, and r1 is saved in r10.

 * PPR save and CPU accounting is not done for the !stack case (XXX why not?)

 * __GEN_COMMON_ENTRY is required to receive the branch from interrupt

 * entry, except in the case of the IEARLY handlers.

 * This switches to virtual mode and sets MSR[RI].

 */

.macro GEN_COMMON name

.macro __GEN_COMMON_ENTRY name

DEFINE_FIXED_SYMBOL(\name\()_common_real)

\name\()_common_real:

	ld	r10,PACAKMSR(r13)	/* get MSR value for kernel */

	/* MSR[RI] is clear iff using SRR regs */

	.if IHSRR == EXC_HV_OR_STD

	BEGIN_FTR_SECTION

	xori	r10,r10,MSR_RI

	END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)

	.elseif ! IHSRR

	xori	r10,r10,MSR_RI

	.endif

	mtmsrd	r10



	.if IVIRT

	.balign IFETCH_ALIGN_BYTES

DEFINE_FIXED_SYMBOL(\name\()_common_virt)

\name\()_common_virt:

	.endif /* IVIRT */

.endm



.macro __GEN_COMMON_BODY name

	.if ISTACK

	andi.	r10,r12,MSR_PR		/* See if coming from user	*/

	mr	r10,r1			/* Save r1			*/
@@ -604,6 +541,11 @@ END_FTR_SECTION_NESTED(CPU_FTR_HAS_PPR,CPU_FTR_HAS_PPR,948) 
	std	r0,GPR0(r1)		/* save r0 in stackframe	*/

	std	r10,GPR1(r1)		/* save r1 in stackframe	*/



	.if ISET_RI

	li	r10,MSR_RI

	mtmsrd	r10,1			/* Set MSR_RI */

	.endif



	.if ISTACK

	.if IKUAP

	kuap_save_amr_and_lock r9, r10, cr1, cr0
@@ -654,7 +596,7 @@ BEGIN_FTR_SECTION_NESTED(66) 
	ld	r10,IAREA+EX_CFAR(r13)

	std	r10,ORIG_GPR3(r1)

END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66)

	GET_CTR(r10, IAREA)

	ld	r10,IAREA+EX_CTR(r13)

	std	r10,_CTR(r1)

	std	r2,GPR2(r1)		/* save r2 in stackframe	*/

	SAVE_4GPRS(3, r1)		/* save r3 - r6 in stackframe   */
@@ -682,6 +624,19 @@ END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66) 
	.endif

.endm



/*

 * On entry r13 points to the paca, r9-r13 are saved in the paca,

 * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and

 * SRR1, and relocation is on.

 *

 * If stack=0, then the stack is already set in r1, and r1 is saved in r10.

 * PPR save and CPU accounting is not done for the !stack case (XXX why not?)

 */

.macro GEN_COMMON name

	__GEN_COMMON_ENTRY \name

	__GEN_COMMON_BODY \name

.endm



/*

 * Restore all registers including H/SRR0/1 saved in a stack frame of a

 * standard exception.
@@ -834,6 +789,7 @@ EXC_VIRT_NONE(0x4000, 0x100) 
INT_DEFINE_BEGIN(system_reset)

	IVEC=0x100

	IAREA=PACA_EXNMI

	IVIRT=0 /* no virt entry point */

	/*

	 * MSR_RI is not enabled, because PACA_EXNMI and nmi stack is

	 * being used, so a nested NMI exception would corrupt it.
@@ -913,6 +869,7 @@ TRAMP_REAL_BEGIN(system_reset_fwnmi) 
#endif /* CONFIG_PPC_PSERIES */



EXC_COMMON_BEGIN(system_reset_common)

	__GEN_COMMON_ENTRY system_reset

	/*

	 * Increment paca->in_nmi then enable MSR_RI. SLB or MCE will be able

	 * to recover, but nested NMI will notice in_nmi and not recover
@@ -928,7 +885,7 @@ EXC_COMMON_BEGIN(system_reset_common) 
	mr	r10,r1

	ld	r1,PACA_NMI_EMERG_SP(r13)

	subi	r1,r1,INT_FRAME_SIZE

	GEN_COMMON system_reset

	__GEN_COMMON_BODY system_reset

	bl	save_nvgprs

	/*

	 * Set IRQS_ALL_DISABLED unconditionally so arch_irqs_disabled does
@@ -973,6 +930,7 @@ EXC_COMMON_BEGIN(system_reset_common) 
INT_DEFINE_BEGIN(machine_check_early)

	IVEC=0x200

	IAREA=PACA_EXMC

	IVIRT=0 /* no virt entry point */

	/*

	 * MSR_RI is not enabled, because PACA_EXMC is being used, so a

	 * nested machine check corrupts it. machine_check_common enables
@@ -990,6 +948,7 @@ INT_DEFINE_END(machine_check_early) 
INT_DEFINE_BEGIN(machine_check)

	IVEC=0x200

	IAREA=PACA_EXMC

	IVIRT=0 /* no virt entry point */

	ISET_RI=0

	IDAR=1

	IDSISR=1
@@ -1022,7 +981,6 @@ TRAMP_KVM_BEGIN(machine_check_kvm) 
	EXCEPTION_RESTORE_REGS EXC_STD



EXC_COMMON_BEGIN(machine_check_early_common)

	mtctr	r10			/* Restore ctr */

	mfspr	r11,SPRN_SRR0

	mfspr	r12,SPRN_SRR1
@@ -1061,7 +1019,7 @@ EXC_COMMON_BEGIN(machine_check_early_common) 
	bgt	cr1,unrecoverable_mce	/* Check if we hit limit of 4 */

	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame */



	GEN_COMMON machine_check_early

	__GEN_COMMON_BODY machine_check_early



BEGIN_FTR_SECTION

	bl	enable_machine_check
@@ -1448,6 +1406,8 @@ EXC_VIRT_END(program_check, 0x4700, 0x100) 
TRAMP_KVM_BEGIN(program_check_kvm)

	GEN_KVM program_check

EXC_COMMON_BEGIN(program_check_common)

	__GEN_COMMON_ENTRY program_check



	/*

	 * It's possible to receive a TM Bad Thing type program check with

	 * userspace register values (in particular r1), but with SRR1 reporting
@@ -1473,11 +1433,11 @@ EXC_COMMON_BEGIN(program_check_common) 
	ld	r1,PACAEMERGSP(r13)	/* Use emergency stack		*/

	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame		*/

	__ISTACK(program_check)=0

	GEN_COMMON program_check

	__GEN_COMMON_BODY program_check

	b 3f

2:

	__ISTACK(program_check)=1

	GEN_COMMON program_check

	__GEN_COMMON_BODY program_check

3:

	bl	save_nvgprs

	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -1861,14 +1821,13 @@ TRAMP_KVM_BEGIN(hmi_exception_kvm) 
	GEN_KVM hmi_exception



EXC_COMMON_BEGIN(hmi_exception_early_common)

	mtctr	r10			/* Restore ctr */

	mfspr	r11,SPRN_HSRR0		/* Save HSRR0 */

	mfspr	r12,SPRN_HSRR1		/* Save HSRR1 */

	mr	r10,r1			/* Save r1 */

	ld	r1,PACAEMERGSP(r13)	/* Use emergency stack for realmode */

	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame		*/



	GEN_COMMON hmi_exception_early

	__GEN_COMMON_BODY hmi_exception_early



	addi	r3,r1,STACK_FRAME_OVERHEAD

	bl	hmi_exception_realmode
@@ -2195,7 +2154,9 @@ EXC_REAL_BEGIN(denorm_exception, 0x1500, 0x100) 
	bne+	denorm_assist

#endif

	KVMTEST denorm_exception, EXC_HV, 0x1500

	INT_SAVE_SRR_AND_JUMP denorm_exception_common, EXC_HV, 1

	mfspr	r11,SPRN_HSRR0

	mfspr	r12,SPRN_HSRR1

	GEN_BRANCH_TO_COMMON denorm_exception, virt=0

EXC_REAL_END(denorm_exception, 0x1500, 0x100)

#ifdef CONFIG_PPC_DENORMALISATION

EXC_VIRT_BEGIN(denorm_exception, 0x5500, 0x100)
@@ -2203,7 +2164,9 @@ EXC_VIRT_BEGIN(denorm_exception, 0x5500, 0x100) 
	mfspr	r10,SPRN_HSRR1

	andis.	r10,r10,(HSRR1_DENORM)@h /* denorm? */

	bne+	denorm_assist

	INT_VIRT_SAVE_SRR_AND_JUMP denorm_exception_common, EXC_HV

	mfspr	r11,SPRN_HSRR0

	mfspr	r12,SPRN_HSRR1

	GEN_BRANCH_TO_COMMON denorm_exception, virt=1

EXC_VIRT_END(denorm_exception, 0x5500, 0x100)

#else

EXC_VIRT_NONE(0x5500, 0x100)
@@ -2374,7 +2337,11 @@ EXC_VIRT_NONE(0x5800, 0x100) 
	std	r12,PACA_EXGEN+EX_R12(r13);		\

	GET_SCRATCH0(r10);				\

	std	r10,PACA_EXGEN+EX_R13(r13);		\

	INT_SAVE_SRR_AND_JUMP soft_nmi_common, _H, 1

	mfspr	r11,SPRN_SRR0;		/* save SRR0 */	\

	mfspr	r12,SPRN_SRR1;		/* and SRR1 */	\

	LOAD_HANDLER(r10, soft_nmi_common);		\

	mtctr	r10;					\

	bctr



/*

 * Branch to soft_nmi_interrupt using the emergency stack. The emergency
@@ -2390,7 +2357,7 @@ EXC_COMMON_BEGIN(soft_nmi_common) 
	ld	r1,PACAEMERGSP(r13)

	subi	r1,r1,INT_FRAME_SIZE

	__ISTACK(decrementer)=0

	GEN_COMMON decrementer

	__GEN_COMMON_BODY decrementer

	bl	save_nvgprs

	addi	r3,r1,STACK_FRAME_OVERHEAD

	bl	soft_nmi_interrupt
@@ -2790,12 +2757,12 @@ handle_dabr_fault: 
h_doorbell_common_msgclr:

	LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))

	PPC_MSGCLR(3)

	b 	h_doorbell_common

	b 	h_doorbell_common_virt



doorbell_super_common_msgclr:

	LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))

	PPC_MSGCLRP(3)

	b 	doorbell_super_common

	b 	doorbell_super_common_virt



/*

 * Called from arch_local_irq_enable when an interrupt needs
@@ -2821,20 +2788,20 @@ _GLOBAL(__replay_interrupt) 
	mfcr	r9

	ori	r12,r12,MSR_EE

	cmpwi	r3,0x900

	beq	decrementer_common

	beq	decrementer_common_virt

	cmpwi	r3,0x500

BEGIN_FTR_SECTION

	beq	h_virt_irq_common

	beq	h_virt_irq_common_virt

FTR_SECTION_ELSE

	beq	hardware_interrupt_common

	beq	hardware_interrupt_common_virt

ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_300)

	cmpwi	r3,0xf00

	beq	performance_monitor_common

	beq	performance_monitor_common_virt

BEGIN_FTR_SECTION

	cmpwi	r3,0xa00

	beq	h_doorbell_common_msgclr

	cmpwi	r3,0xe60

	beq	hmi_exception_common

	beq	hmi_exception_common_virt

FTR_SECTION_ELSE

	cmpwi	r3,0xa00

	beq	doorbell_super_common_msgclr