[PATCH v6 8/8] powernv/pseries: consolidate code for mce early handling.

[Mahesh J Salgaonkar]

From: Mahesh Salgaonkar <mahesh at linux.vnet.ibm.com>

Now that other platforms also implements real mode mce handler,
lets consolidate the code by sharing existing powernv machine check
early code. Rename machine_check_powernv_early to
machine_check_common_early and reuse the code.

Signed-off-by: Mahesh Salgaonkar <mahesh at linux.vnet.ibm.com>
---
 arch/powerpc/kernel/exceptions-64s.S |   56 +++++++---------------------------
 1 file changed, 11 insertions(+), 45 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 0038596b7906..3e877ec55d50 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -243,14 +243,13 @@ EXC_REAL_BEGIN(machine_check, 0x200, 0x100)
 	SET_SCRATCH0(r13)		/* save r13 */
 	EXCEPTION_PROLOG_0(PACA_EXMC)
 BEGIN_FTR_SECTION
-	b	machine_check_powernv_early
+	b	machine_check_common_early
 FTR_SECTION_ELSE
 	b	machine_check_pSeries_0
 ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
 EXC_REAL_END(machine_check, 0x200, 0x100)
 EXC_VIRT_NONE(0x4200, 0x100)
-TRAMP_REAL_BEGIN(machine_check_powernv_early)
-BEGIN_FTR_SECTION
+TRAMP_REAL_BEGIN(machine_check_common_early)
 	EXCEPTION_PROLOG_1(PACA_EXMC, NOTEST, 0x200)
 	/*
 	 * Register contents:
@@ -306,7 +305,9 @@ BEGIN_FTR_SECTION
 	/* Save r9 through r13 from EXMC save area to stack frame. */
 	EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
 	mfmsr	r11			/* get MSR value */
+BEGIN_FTR_SECTION
 	ori	r11,r11,MSR_ME		/* turn on ME bit */
+END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
 	ori	r11,r11,MSR_RI		/* turn on RI bit */
 	LOAD_HANDLER(r12, machine_check_handle_early)
 1:	mtspr	SPRN_SRR0,r12
@@ -325,7 +326,6 @@ BEGIN_FTR_SECTION
 	andc	r11,r11,r10		/* Turn off MSR_ME */
 	b	1b
 	b	.	/* prevent speculative execution */
-END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
 
 TRAMP_REAL_BEGIN(machine_check_pSeries)
 	.globl machine_check_fwnmi
@@ -333,7 +333,7 @@ machine_check_fwnmi:
 	SET_SCRATCH0(r13)		/* save r13 */
 	EXCEPTION_PROLOG_0(PACA_EXMC)
 BEGIN_FTR_SECTION
-	b	machine_check_pSeries_early
+	b	machine_check_common_early
 END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
 machine_check_pSeries_0:
 	EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST_PR, 0x200)
@@ -346,45 +346,6 @@ machine_check_pSeries_0:
 
 TRAMP_KVM_SKIP(PACA_EXMC, 0x200)
 
-TRAMP_REAL_BEGIN(machine_check_pSeries_early)
-BEGIN_FTR_SECTION
-	EXCEPTION_PROLOG_1(PACA_EXMC, NOTEST, 0x200)
-	mr	r10,r1			/* Save r1 */
-	ld	r1,PACAMCEMERGSP(r13)	/* Use MC emergency stack */
-	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame		*/
-	mfspr	r11,SPRN_SRR0		/* Save SRR0 */
-	mfspr	r12,SPRN_SRR1		/* Save SRR1 */
-	EXCEPTION_PROLOG_COMMON_1()
-	EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
-	EXCEPTION_PROLOG_COMMON_3(0x200)
-	addi	r3,r1,STACK_FRAME_OVERHEAD
-	BRANCH_LINK_TO_FAR(machine_check_early) /* Function call ABI */
-
-	/* Move original SRR0 and SRR1 into the respective regs */
-	ld	r9,_MSR(r1)
-	mtspr	SPRN_SRR1,r9
-	ld	r3,_NIP(r1)
-	mtspr	SPRN_SRR0,r3
-	ld	r9,_CTR(r1)
-	mtctr	r9
-	ld	r9,_XER(r1)
-	mtxer	r9
-	ld	r9,_LINK(r1)
-	mtlr	r9
-	REST_GPR(0, r1)
-	REST_8GPRS(2, r1)
-	REST_GPR(10, r1)
-	ld	r11,_CCR(r1)
-	mtcr	r11
-	REST_GPR(11, r1)
-	REST_2GPRS(12, r1)
-	/* restore original r1. */
-	ld	r1,GPR1(r1)
-	SET_SCRATCH0(r13)		/* save r13 */
-	EXCEPTION_PROLOG_0(PACA_EXMC)
-	b	machine_check_pSeries_0
-END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
-
 EXC_COMMON_BEGIN(machine_check_common)
 	/*
 	 * Machine check is different because we use a different
@@ -483,6 +444,9 @@ EXC_COMMON_BEGIN(machine_check_handle_early)
 	bl	machine_check_early
 	std	r3,RESULT(r1)	/* Save result */
 	ld	r12,_MSR(r1)
+BEGIN_FTR_SECTION
+	bne	9f			/* pSeries: continue to V mode. */
+END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
 
 #ifdef	CONFIG_PPC_P7_NAP
 	/*
@@ -564,7 +528,9 @@ EXC_COMMON_BEGIN(machine_check_handle_early)
 9:
 	/* Deliver the machine check to host kernel in V mode. */
 	MACHINE_CHECK_HANDLER_WINDUP
-	b	machine_check_pSeries
+	SET_SCRATCH0(r13)		/* save r13 */
+	EXCEPTION_PROLOG_0(PACA_EXMC)
+	b	machine_check_pSeries_0
 
 EXC_COMMON_BEGIN(unrecover_mce)
 	/* Invoke machine_check_exception to print MCE event and panic. */