[PATCH 00/11] Refactor exception entry on 40x/6xx/8xx

[PATCH 00/11] Refactor exception entry on 40x/6xx/8xx

[Christophe Leroy]

This serie refactors exception entry macros for 40x, 6xx and 8xx

This serie will benefit to the implementation of CONFIG_VMAP, and also
to Ben's serie on MSR_EE.

First patch of this serie is a part of the CONFIG_THREAD_INFO_IN_TASK serie.
This avoids a conflict between the two series.

Christophe Leroy (11):
  powerpc/32: Rename THREAD_INFO to TASK_STACK
  powerpc/32: Refactor EXCEPTION entry macros for head_8xx.S and
    head_32.S
  powerpc/32: Add a macro for setting MSR_RI in EXCEPTION_PROLOG_2
  powerpc/32: add CLR_MSR_WE() in EXCEPTION_PROLOG in head_32.h
  powerpc/32: add START_EXCEPTION() in head_32.h
  powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it
  powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG
  powerpc/40x: add exception frame marker
  powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG
  powerpc/40x: Add EXC_XFER_TEMPLATE_CRITICAL()
  powerpc/40x: Refactor exception entry macros by using head_32.h

 arch/powerpc/kernel/asm-offsets.c    |   2 +-
 arch/powerpc/kernel/entry_32.S       |  11 +---
 arch/powerpc/kernel/head_32.S        | 101 ++--------------------------
 arch/powerpc/kernel/head_32.h        | 124 +++++++++++++++++++++++++++++++++++
 arch/powerpc/kernel/head_40x.S       | 120 ++++++++-------------------------
 arch/powerpc/kernel/head_8xx.S       | 103 ++---------------------------
 arch/powerpc/kernel/head_booke.h     |   4 +-
 arch/powerpc/kernel/head_fsl_booke.S |   2 +-
 8 files changed, 167 insertions(+), 300 deletions(-)
 create mode 100644 arch/powerpc/kernel/head_32.h

-- 
2.13.3

[PATCH 01/11] powerpc/32: Rename THREAD_INFO to TASK_STACK

[Christophe Leroy]

This patch renames THREAD_INFO to TASK_STACK, because it is in fact
the offset of the pointer to the stack in task_struct so this pointer
will not be impacted by the move of THREAD_INFO.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kernel/asm-offsets.c    | 2 +-
 arch/powerpc/kernel/entry_32.S       | 2 +-
 arch/powerpc/kernel/head_32.S        | 2 +-
 arch/powerpc/kernel/head_40x.S       | 4 ++--
 arch/powerpc/kernel/head_8xx.S       | 2 +-
 arch/powerpc/kernel/head_booke.h     | 4 ++--
 arch/powerpc/kernel/head_fsl_booke.S | 2 +-
 7 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 9ffc72ded73a..23456ba3410a 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -90,7 +90,7 @@ int main(void)
 	DEFINE(SIGSEGV, SIGSEGV);
 	DEFINE(NMI_MASK, NMI_MASK);
 #else
-	OFFSET(THREAD_INFO, task_struct, stack);
+	OFFSET(TASK_STACK, task_struct, stack);
 	DEFINE(THREAD_INFO_GAP, _ALIGN_UP(sizeof(struct thread_info), 16));
 	OFFSET(KSP_LIMIT, thread_struct, ksp_limit);
 #endif /* CONFIG_PPC64 */
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 0768dfd8a64e..3f83e71ae43f 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -1166,7 +1166,7 @@ ret_from_debug_exc:
 	mfspr	r9,SPRN_SPRG_THREAD
 	lwz	r10,SAVED_KSP_LIMIT(r1)
 	stw	r10,KSP_LIMIT(r9)
-	lwz	r9,THREAD_INFO-THREAD(r9)
+	lwz	r9,TASK_STACK-THREAD(r9)
 	CURRENT_THREAD_INFO(r10, r1)
 	lwz	r10,TI_PREEMPT(r10)
 	stw	r10,TI_PREEMPT(r9)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 05b08db3901d..9268e5e87949 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -261,7 +261,7 @@ __secondary_hold_acknowledge:
 	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
 	beq	1f;		\
 	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,THREAD_INFO-THREAD(r11);	\
+	lwz	r11,TASK_STACK-THREAD(r11);	\
 	addi	r11,r11,THREAD_SIZE;	\
 	tophys(r11,r11);	\
 1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index b19d78410511..3088c9f29f5e 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -115,7 +115,7 @@ _ENTRY(saved_ksp_limit)
 	andi.	r11,r11,MSR_PR;						     \
 	beq	1f;							     \
 	mfspr	r1,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r1,THREAD_INFO-THREAD(r1); /* this thread's kernel stack   */\
+	lwz	r1,TASK_STACK-THREAD(r1); /* this thread's kernel stack   */\
 	addi	r1,r1,THREAD_SIZE;					     \
 1:	subi	r1,r1,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
 	tophys(r11,r1);							     \
@@ -158,7 +158,7 @@ _ENTRY(saved_ksp_limit)
 	beq	1f;							     \
 	/* COMING FROM USER MODE */					     \
 	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
+	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
 1:	addi	r11,r11,THREAD_SIZE-INT_FRAME_SIZE; /* Alloc an excpt frm  */\
 	tophys(r11,r11);						     \
 	stw	r10,_CCR(r11);          /* save various registers	   */\
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 20cc816b3508..ca9207013579 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -142,7 +142,7 @@ instruction_counter:
 	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
 	beq	1f;		\
 	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,THREAD_INFO-THREAD(r11);	\
+	lwz	r11,TASK_STACK-THREAD(r11);	\
 	addi	r11,r11,THREAD_SIZE;	\
 	tophys(r11,r11);	\
 1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index 306e26c073a0..69e80e6d0d16 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -55,7 +55,7 @@ END_BTB_FLUSH_SECTION
 	beq	1f;							     \
 	BOOKE_CLEAR_BTB(r11)						\
 	/* if from user, start at top of this thread's kernel stack */       \
-	lwz	r11, THREAD_INFO-THREAD(r10);				     \
+	lwz	r11, TASK_STACK - THREAD(r10);				     \
 	ALLOC_STACK_FRAME(r11, THREAD_SIZE);				     \
 1 :	subi	r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */     \
 	stw	r13, _CCR(r11);		/* save various registers */	     \
@@ -142,7 +142,7 @@ END_BTB_FLUSH_SECTION
 	BOOKE_CLEAR_BTB(r10)						\
 	andi.	r11,r11,MSR_PR;						     \
 	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
+	lwz	r11, TASK_STACK - THREAD(r11); /* this thread's kernel stack */\
 	addi	r11,r11,EXC_LVL_FRAME_OVERHEAD;	/* allocate stack frame    */\
 	beq	1f;							     \
 	/* COMING FROM USER MODE */					     \
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 2386ce2a9c6e..acf9a58c3c00 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -717,7 +717,7 @@ finish_tlb_load:
 
 	/* Get the next_tlbcam_idx percpu var */
 #ifdef CONFIG_SMP
-	lwz	r12, THREAD_INFO-THREAD(r12)
+	lwz	r12, TASK_STACK-THREAD(r12)
 	lwz	r15, TI_CPU(r12)
 	lis     r14, __per_cpu_offset@h
 	ori     r14, r14, __per_cpu_offset@l
-- 
2.13.3

[PATCH 02/11] powerpc/32: Refactor EXCEPTION entry macros for head_8xx.S and head_32.S

[Christophe Leroy]

EXCEPTION_PROLOG is similar in head_8xx.S and head_32.S

This patch creates head_32.h and moves EXCEPTION_PROLOG macro
into it.

It also moves EXCEPTION() and EXC_XFER_XXXX() macros which are also
similar. For that, the 8xx needs to define a dummy DO_KVM asm macro.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.S  |  99 +--------------------------------------
 arch/powerpc/kernel/head_32.h  | 104 +++++++++++++++++++++++++++++++++++++++++
 arch/powerpc/kernel/head_8xx.S | 101 ++-------------------------------------
 3 files changed, 111 insertions(+), 193 deletions(-)
 create mode 100644 arch/powerpc/kernel/head_32.h

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 9268e5e87949..a5efcdc78e8e 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -37,6 +37,8 @@
 #include <asm/export.h>
 #include <asm/feature-fixups.h>
 
+#include "head_32.h"
+
 /* 601 only have IBAT; cr0.eq is set on 601 when using this macro */
 #define LOAD_BAT(n, reg, RA, RB)	\
 	/* see the comment for clear_bats() -- Cort */ \
@@ -242,103 +244,6 @@ __secondary_hold_spinloop:
 __secondary_hold_acknowledge:
 	.long	-1
 
-/*
- * Exception entry code.  This code runs with address translation
- * turned off, i.e. using physical addresses.
- * We assume sprg3 has the physical address of the current
- * task's thread_struct.
- */
-#define EXCEPTION_PROLOG	\
-	mtspr	SPRN_SPRG_SCRATCH0,r10;	\
-	mtspr	SPRN_SPRG_SCRATCH1,r11;	\
-	mfcr	r10;		\
-	EXCEPTION_PROLOG_1;	\
-	EXCEPTION_PROLOG_2
-
-#define EXCEPTION_PROLOG_1	\
-	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel */ \
-	andi.	r11,r11,MSR_PR;	\
-	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
-	beq	1f;		\
-	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,TASK_STACK-THREAD(r11);	\
-	addi	r11,r11,THREAD_SIZE;	\
-	tophys(r11,r11);	\
-1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
-
-
-#define EXCEPTION_PROLOG_2	\
-	stw	r10,_CCR(r11);		/* save registers */ \
-	stw	r12,GPR12(r11);	\
-	stw	r9,GPR9(r11);	\
-	mfspr	r10,SPRN_SPRG_SCRATCH0;	\
-	stw	r10,GPR10(r11);	\
-	mfspr	r12,SPRN_SPRG_SCRATCH1;	\
-	stw	r12,GPR11(r11);	\
-	mflr	r10;		\
-	stw	r10,_LINK(r11);	\
-	mfspr	r12,SPRN_SRR0;	\
-	mfspr	r9,SPRN_SRR1;	\
-	stw	r1,GPR1(r11);	\
-	stw	r1,0(r11);	\
-	tovirt(r1,r11);			/* set new kernel sp */	\
-	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
-	MTMSRD(r10);			/* (except for mach check in rtas) */ \
-	stw	r0,GPR0(r11);	\
-	lis	r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
-	addi	r10,r10,STACK_FRAME_REGS_MARKER@l; \
-	stw	r10,8(r11);	\
-	SAVE_4GPRS(3, r11);	\
-	SAVE_2GPRS(7, r11)
-
-/*
- * Note: code which follows this uses cr0.eq (set if from kernel),
- * r11, r12 (SRR0), and r9 (SRR1).
- *
- * Note2: once we have set r1 we are in a position to take exceptions
- * again, and we could thus set MSR:RI at that point.
- */
-
-/*
- * Exception vectors.
- */
-#define EXCEPTION(n, label, hdlr, xfer)		\
-	. = n;					\
-	DO_KVM n;				\
-label:						\
-	EXCEPTION_PROLOG;			\
-	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
-	xfer(n, hdlr)
-
-#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
-	li	r10,trap;					\
-	stw	r10,_TRAP(r11);					\
-	li	r10,MSR_KERNEL;					\
-	copyee(r10, r9);					\
-	bl	tfer;						\
-i##n:								\
-	.long	hdlr;						\
-	.long	ret
-
-#define COPY_EE(d, s)		rlwimi d,s,0,16,16
-#define NOCOPY(d, s)
-
-#define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
-			  ret_from_except_full)
-
-#define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
-			  ret_from_except)
-
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
 /* System reset */
 /* core99 pmac starts the seconary here by changing the vector, and
    putting it back to what it was (unknown_exception) when done.  */
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
new file mode 100644
index 000000000000..7356c27d2136
--- /dev/null
+++ b/arch/powerpc/kernel/head_32.h
@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __HEAD_32_H__
+#define __HEAD_32_H__
+
+#include <asm/ptrace.h>	/* for STACK_FRAME_REGS_MARKER */
+
+/*
+ * Exception entry code.  This code runs with address translation
+ * turned off, i.e. using physical addresses.
+ * We assume sprg3 has the physical address of the current
+ * task's thread_struct.
+ */
+#define EXCEPTION_PROLOG	\
+	mtspr	SPRN_SPRG_SCRATCH0,r10;	\
+	mtspr	SPRN_SPRG_SCRATCH1,r11;	\
+	mfcr	r10;		\
+	EXCEPTION_PROLOG_1;	\
+	EXCEPTION_PROLOG_2
+
+#define EXCEPTION_PROLOG_1	\
+	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel */ \
+	andi.	r11,r11,MSR_PR;	\
+	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
+	beq	1f;		\
+	mfspr	r11,SPRN_SPRG_THREAD;	\
+	lwz	r11,TASK_STACK-THREAD(r11);	\
+	addi	r11,r11,THREAD_SIZE;	\
+	tophys(r11,r11);	\
+1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
+
+
+#define EXCEPTION_PROLOG_2	\
+	stw	r10,_CCR(r11);		/* save registers */ \
+	stw	r12,GPR12(r11);	\
+	stw	r9,GPR9(r11);	\
+	mfspr	r10,SPRN_SPRG_SCRATCH0;	\
+	stw	r10,GPR10(r11);	\
+	mfspr	r12,SPRN_SPRG_SCRATCH1;	\
+	stw	r12,GPR11(r11);	\
+	mflr	r10;		\
+	stw	r10,_LINK(r11);	\
+	mfspr	r12,SPRN_SRR0;	\
+	mfspr	r9,SPRN_SRR1;	\
+	stw	r1,GPR1(r11);	\
+	stw	r1,0(r11);	\
+	tovirt(r1,r11);			/* set new kernel sp */	\
+	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
+	MTMSRD(r10);			/* (except for mach check in rtas) */ \
+	stw	r0,GPR0(r11);	\
+	lis	r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
+	addi	r10,r10,STACK_FRAME_REGS_MARKER@l; \
+	stw	r10,8(r11);	\
+	SAVE_4GPRS(3, r11);	\
+	SAVE_2GPRS(7, r11)
+
+/*
+ * Note: code which follows this uses cr0.eq (set if from kernel),
+ * r11, r12 (SRR0), and r9 (SRR1).
+ *
+ * Note2: once we have set r1 we are in a position to take exceptions
+ * again, and we could thus set MSR:RI at that point.
+ */
+
+/*
+ * Exception vectors.
+ */
+#define EXCEPTION(n, label, hdlr, xfer)		\
+	. = n;					\
+	DO_KVM n;				\
+label:						\
+	EXCEPTION_PROLOG;			\
+	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
+	xfer(n, hdlr)
+
+#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
+	li	r10,trap;					\
+	stw	r10,_TRAP(r11);					\
+	li	r10,MSR_KERNEL;					\
+	copyee(r10, r9);					\
+	bl	tfer;						\
+i##n:								\
+	.long	hdlr;						\
+	.long	ret
+
+#define COPY_EE(d, s)		rlwimi d,s,0,MSR_EE
+#define NOCOPY(d, s)
+
+#define EXC_XFER_STD(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
+			  ret_from_except_full)
+
+#define EXC_XFER_LITE(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
+			  ret_from_except)
+
+#define EXC_XFER_EE(n, hdlr)		\
+	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
+			  ret_from_except_full)
+
+#define EXC_XFER_EE_LITE(n, hdlr)	\
+	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
+			  ret_from_except)
+
+#endif /* __HEAD_32_H__ */
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index ca9207013579..d9c5bc48bef0 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -33,6 +33,11 @@
 #include <asm/export.h>
 #include <asm/code-patching-asm.h>
 
+.macro DO_KVM intno
+.endm
+
+#include "head_32.h"
+
 #if CONFIG_TASK_SIZE <= 0x80000000 && CONFIG_PAGE_OFFSET >= 0x80000000
 /* By simply checking Address >= 0x80000000, we know if its a kernel address */
 #define SIMPLE_KERNEL_ADDRESS		1
@@ -123,102 +128,6 @@ instruction_counter:
 	.space	4
 #endif
 
-/*
- * Exception entry code.  This code runs with address translation
- * turned off, i.e. using physical addresses.
- * We assume sprg3 has the physical address of the current
- * task's thread_struct.
- */
-#define EXCEPTION_PROLOG	\
-	mtspr	SPRN_SPRG_SCRATCH0, r10;	\
-	mtspr	SPRN_SPRG_SCRATCH1, r11;	\
-	mfcr	r10;		\
-	EXCEPTION_PROLOG_1;	\
-	EXCEPTION_PROLOG_2
-
-#define EXCEPTION_PROLOG_1	\
-	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel */ \
-	andi.	r11,r11,MSR_PR;	\
-	tophys(r11,r1);			/* use tophys(r1) if kernel */ \
-	beq	1f;		\
-	mfspr	r11,SPRN_SPRG_THREAD;	\
-	lwz	r11,TASK_STACK-THREAD(r11);	\
-	addi	r11,r11,THREAD_SIZE;	\
-	tophys(r11,r11);	\
-1:	subi	r11,r11,INT_FRAME_SIZE	/* alloc exc. frame */
-
-
-#define EXCEPTION_PROLOG_2	\
-	stw	r10,_CCR(r11);		/* save registers */ \
-	stw	r12,GPR12(r11);	\
-	stw	r9,GPR9(r11);	\
-	mfspr	r10,SPRN_SPRG_SCRATCH0;	\
-	stw	r10,GPR10(r11);	\
-	mfspr	r12,SPRN_SPRG_SCRATCH1;	\
-	stw	r12,GPR11(r11);	\
-	mflr	r10;		\
-	stw	r10,_LINK(r11);	\
-	mfspr	r12,SPRN_SRR0;	\
-	mfspr	r9,SPRN_SRR1;	\
-	stw	r1,GPR1(r11);	\
-	stw	r1,0(r11);	\
-	tovirt(r1,r11);			/* set new kernel sp */	\
-	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
-	mtmsr	r10;		\
-	stw	r0,GPR0(r11);	\
-	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
-	addi	r10, r10, STACK_FRAME_REGS_MARKER@l; \
-	stw	r10, 8(r11);	\
-	SAVE_4GPRS(3, r11);	\
-	SAVE_2GPRS(7, r11)
-
-/*
- * Note: code which follows this uses cr0.eq (set if from kernel),
- * r11, r12 (SRR0), and r9 (SRR1).
- *
- * Note2: once we have set r1 we are in a position to take exceptions
- * again, and we could thus set MSR:RI at that point.
- */
-
-/*
- * Exception vectors.
- */
-#define EXCEPTION(n, label, hdlr, xfer)		\
-	. = n;					\
-label:						\
-	EXCEPTION_PROLOG;			\
-	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
-	xfer(n, hdlr)
-
-#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
-	li	r10,trap;					\
-	stw	r10,_TRAP(r11);					\
-	li	r10,MSR_KERNEL;					\
-	copyee(r10, r9);					\
-	bl	tfer;						\
-i##n:								\
-	.long	hdlr;						\
-	.long	ret
-
-#define COPY_EE(d, s)		rlwimi d,s,0,16,16
-#define NOCOPY(d, s)
-
-#define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full,	\
-			  ret_from_except_full)
-
-#define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
-			  ret_from_except)
-
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
 /* System reset */
 	EXCEPTION(0x100, Reset, system_reset_exception, EXC_XFER_STD)
 
-- 
2.13.3

[PATCH 03/11] powerpc/32: Add a macro for setting MSR_RI in EXCEPTION_PROLOG_2

[Christophe Leroy]

Setting MSR_RI applies to head_32 and head_8xx, but not to
head_40x. So in order to refactor EXCEPTION_PROLOG for 40x too,
this patch adds a macro for setting MSR_RI.

In the meantime, this gives the opportunity to make it
simpler on the 8xx as writing in SPRN_EID sets MSR_RI.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.S  | 2 ++
 arch/powerpc/kernel/head_32.h  | 7 +++++--
 arch/powerpc/kernel/head_8xx.S | 2 ++
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index a5efcdc78e8e..edc5e78faf08 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -37,6 +37,8 @@
 #include <asm/export.h>
 #include <asm/feature-fixups.h>
 
+#define SET_AND_STORE_MSR_RI(reg)	li reg,MSR_KERNEL & ~(MSR_IR|MSR_DR); MTMSRD(reg)
+
 #include "head_32.h"
 
 /* 601 only have IBAT; cr0.eq is set on 601 when using this macro */
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 7356c27d2136..9e6fb9d468f0 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -4,6 +4,10 @@
 
 #include <asm/ptrace.h>	/* for STACK_FRAME_REGS_MARKER */
 
+#ifndef SET_AND_STORE_MSR_RI
+#define SET_AND_STORE_MSR_RI(reg)
+#endif
+
 /*
  * Exception entry code.  This code runs with address translation
  * turned off, i.e. using physical addresses.
@@ -44,8 +48,7 @@
 	stw	r1,GPR1(r11);	\
 	stw	r1,0(r11);	\
 	tovirt(r1,r11);			/* set new kernel sp */	\
-	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
-	MTMSRD(r10);			/* (except for mach check in rtas) */ \
+	SET_AND_STORE_MSR_RI(r10);	/* can take exceptions */ \
 	stw	r0,GPR0(r11);	\
 	lis	r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
 	addi	r10,r10,STACK_FRAME_REGS_MARKER@l; \
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index d9c5bc48bef0..00dacec2b0d1 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -36,6 +36,8 @@
 .macro DO_KVM intno
 .endm
 
+#define SET_AND_STORE_MSR_RI(reg)	mtspr	SPRN_EID, reg
+
 #include "head_32.h"
 
 #if CONFIG_TASK_SIZE <= 0x80000000 && CONFIG_PAGE_OFFSET >= 0x80000000
-- 
2.13.3

[PATCH 04/11] powerpc/32: add CLR_MSR_WE() in EXCEPTION_PROLOG in head_32.h

[Christophe Leroy]

Add CLR_MSR_WE() macro to allow 40x to clear
that bit from the register containing msr value.

This is the only difference between common EXCEPTION_PROLOG
and 40x one. This patch will allow 40x to use the common one.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 9e6fb9d468f0..643dd8d34aac 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -8,6 +8,10 @@
 #define SET_AND_STORE_MSR_RI(reg)
 #endif
 
+#ifndef CLR_MSR_WE
+#define CLR_MSR_WE(reg)
+#endif
+
 /*
  * Exception entry code.  This code runs with address translation
  * turned off, i.e. using physical addresses.
@@ -49,6 +53,7 @@
 	stw	r1,0(r11);	\
 	tovirt(r1,r11);			/* set new kernel sp */	\
 	SET_AND_STORE_MSR_RI(r10);	/* can take exceptions */ \
+	CLR_MSR_WE(r9);		\
 	stw	r0,GPR0(r11);	\
 	lis	r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
 	addi	r10,r10,STACK_FRAME_REGS_MARKER@l; \
-- 
2.13.3

[PATCH 05/11] powerpc/32: add START_EXCEPTION() in head_32.h

[Christophe Leroy]

Add START_EXCEPTION() in head_32.h for preparing the use
of head_32.h in head_40x.S

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_32.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 643dd8d34aac..f77f13142410 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -72,10 +72,13 @@
 /*
  * Exception vectors.
  */
-#define EXCEPTION(n, label, hdlr, xfer)		\
+#define	START_EXCEPTION(n, label)		\
 	. = n;					\
 	DO_KVM n;				\
-label:						\
+label:
+
+#define EXCEPTION(n, label, hdlr, xfer)		\
+	START_EXCEPTION(n, label)		\
 	EXCEPTION_PROLOG;			\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;	\
 	xfer(n, hdlr)
-- 
2.13.3

[PATCH 06/11] powerpc/32: move LOAD_MSR_KERNEL() into head_32.h and use it

[Christophe Leroy]

As preparation for using head_32.h for head_40x.S, move
LOAD_MSR_KERNEL() there and use it to load r10 with MSR_KERNEL value.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/entry_32.S |  9 +--------
 arch/powerpc/kernel/head_32.h  | 11 ++++++++++-
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 3f83e71ae43f..24d93231665b 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -37,14 +37,7 @@
 #include <asm/feature-fixups.h>
 #include <asm/barrier.h>
 
-/*
- * MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE.
- */
-#if MSR_KERNEL >= 0x10000
-#define LOAD_MSR_KERNEL(r, x)	lis r,(x)@h; ori r,r,(x)@l
-#else
-#define LOAD_MSR_KERNEL(r, x)	li r,(x)
-#endif
+#include "head_32.h"
 
 /*
  * Align to 4k in order to ensure that all functions modyfing srr0/srr1
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index f77f13142410..e302afd40d0a 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -13,6 +13,15 @@
 #endif
 
 /*
+ * MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE.
+ */
+#if MSR_KERNEL >= 0x10000
+#define LOAD_MSR_KERNEL(r, x)	lis r,(x)@h; ori r,r,(x)@l
+#else
+#define LOAD_MSR_KERNEL(r, x)	li r,(x)
+#endif
+
+/*
  * Exception entry code.  This code runs with address translation
  * turned off, i.e. using physical addresses.
  * We assume sprg3 has the physical address of the current
@@ -86,7 +95,7 @@
 #define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret)	\
 	li	r10,trap;					\
 	stw	r10,_TRAP(r11);					\
-	li	r10,MSR_KERNEL;					\
+	LOAD_MSR_KERNEL(r10, MSR_KERNEL);			\
 	copyee(r10, r9);					\
 	bl	tfer;						\
 i##n:								\
-- 
2.13.3

[PATCH 07/11] powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG

[Christophe Leroy]

Unlike said in the comment, r1 is not reused by the critical
exception handler, as it uses a dedicated critirq_ctx stack.
Decrementing r1 early is then unneeded.

Should the above be valid, the code is crap buggy anyway as
r1 gets some intermediate values that would jeopardise the
whole process (for instance after mfspr   r1,SPRN_SPRG_THREAD)

Using SPRN_SPRG_SCRATCH2 to save r1 is then not needed, r11 can be
used instead. This avoids one mtspr and one mfspr and makes the
prolog closer to what's done on 6xx and 8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 3088c9f29f5e..59f6f53f1ac2 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -102,23 +102,20 @@ _ENTRY(saved_ksp_limit)
  * Exception vector entry code. This code runs with address translation
  * turned off (i.e. using physical addresses). We assume SPRG_THREAD has
  * the physical address of the current task thread_struct.
- * Note that we have to have decremented r1 before we write to any fields
- * of the exception frame, since a critical interrupt could occur at any
- * time, and it will write to the area immediately below the current r1.
  */
 #define NORMAL_EXCEPTION_PROLOG						     \
 	mtspr	SPRN_SPRG_SCRATCH0,r10;	/* save two registers to work with */\
 	mtspr	SPRN_SPRG_SCRATCH1,r11;					     \
-	mtspr	SPRN_SPRG_SCRATCH2,r1;					     \
 	mfcr	r10;			/* save CR in r10 for now	   */\
 	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel    */\
 	andi.	r11,r11,MSR_PR;						     \
-	beq	1f;							     \
-	mfspr	r1,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r1,TASK_STACK-THREAD(r1); /* this thread's kernel stack   */\
-	addi	r1,r1,THREAD_SIZE;					     \
-1:	subi	r1,r1,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
 	tophys(r11,r1);							     \
+	beq	1f;							     \
+	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
+	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
+	addi	r11,r11,THREAD_SIZE;					     \
+	tophys(r11,r11);						     \
+1:	subi	r11,r11,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
 	stw	r10,_CCR(r11);          /* save various registers	   */\
 	stw	r12,GPR12(r11);						     \
 	stw	r9,GPR9(r11);						     \
@@ -128,11 +125,11 @@ _ENTRY(saved_ksp_limit)
 	stw	r12,GPR11(r11);						     \
 	mflr	r10;							     \
 	stw	r10,_LINK(r11);						     \
-	mfspr	r10,SPRN_SPRG_SCRATCH2;					     \
 	mfspr	r12,SPRN_SRR0;						     \
-	stw	r10,GPR1(r11);						     \
+	stw	r1,GPR1(r11);						     \
 	mfspr	r9,SPRN_SRR1;						     \
-	stw	r10,0(r11);						     \
+	stw	r1,0(r11);						     \
+	tovirt(r1,r11);			/* set new kernel sp */	\
 	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
 	stw	r0,GPR0(r11);						     \
 	SAVE_4GPRS(3, r11);						     \
-- 
2.13.3

[PATCH 08/11] powerpc/40x: add exception frame marker

[Christophe Leroy]

This patch adds STACK_FRAME_REGS_MARKER in the stack at exception entry
in order to see interrupts in call traces as below:

[    0.013964] Call Trace:
[    0.014014] [c0745db0] [c007a9d4] tick_periodic.constprop.5+0xd8/0x104 (unreliable)
[    0.014086] [c0745dc0] [c007aa20] tick_handle_periodic+0x20/0x9c
[    0.014181] [c0745de0] [c0009cd0] timer_interrupt+0xa0/0x264
[    0.014258] [c0745e10] [c000e484] ret_from_except+0x0/0x14
[    0.014390] --- interrupt: 901 at console_unlock.part.7+0x3f4/0x528
[    0.014390]     LR = console_unlock.part.7+0x3f0/0x528
[    0.014455] [c0745ee0] [c0050334] console_unlock.part.7+0x114/0x528 (unreliable)
[    0.014542] [c0745f30] [c00524e0] register_console+0x3d8/0x44c
[    0.014625] [c0745f60] [c0675aac] cpm_uart_console_init+0x18/0x2c
[    0.014709] [c0745f70] [c06614f4] console_init+0x114/0x1cc
[    0.014795] [c0745fb0] [c0658b68] start_kernel+0x300/0x3d8
[    0.014864] [c0745ff0] [c00022cc] start_here+0x44/0x98

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 59f6f53f1ac2..f3bfb695f952 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -132,6 +132,9 @@ _ENTRY(saved_ksp_limit)
 	tovirt(r1,r11);			/* set new kernel sp */	\
 	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
 	stw	r0,GPR0(r11);						     \
+	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */\
+	addi	r10, r10, STACK_FRAME_REGS_MARKER@l;			     \
+	stw	r10, 8(r11);						     \
 	SAVE_4GPRS(3, r11);						     \
 	SAVE_2GPRS(7, r11)
 
@@ -174,6 +177,9 @@ _ENTRY(saved_ksp_limit)
 	tovirt(r1,r11);							     \
 	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
 	stw	r0,GPR0(r11);						     \
+	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */\
+	addi	r10, r10, STACK_FRAME_REGS_MARKER@l;			     \
+	stw	r10, 8(r11);						     \
 	SAVE_4GPRS(3, r11);						     \
 	SAVE_2GPRS(7, r11)
 
-- 
2.13.3

[PATCH 09/11] powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG

[Christophe Leroy]

This patch splits NORMAL_EXCEPTION_PROLOG in the same way as in
head_8xx.S and head_32.S and renames it EXCEPTION_PROLOG() as well
to match head_32.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index f3bfb695f952..1203075c0c1a 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -103,10 +103,14 @@ _ENTRY(saved_ksp_limit)
  * turned off (i.e. using physical addresses). We assume SPRG_THREAD has
  * the physical address of the current task thread_struct.
  */
-#define NORMAL_EXCEPTION_PROLOG						     \
+#define EXCEPTION_PROLOG						     \
 	mtspr	SPRN_SPRG_SCRATCH0,r10;	/* save two registers to work with */\
 	mtspr	SPRN_SPRG_SCRATCH1,r11;					     \
 	mfcr	r10;			/* save CR in r10 for now	   */\
+	EXCEPTION_PROLOG_1;						     \
+	EXCEPTION_PROLOG_2
+
+#define EXCEPTION_PROLOG_1						     \
 	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel    */\
 	andi.	r11,r11,MSR_PR;						     \
 	tophys(r11,r1);							     \
@@ -115,7 +119,9 @@ _ENTRY(saved_ksp_limit)
 	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
 	addi	r11,r11,THREAD_SIZE;					     \
 	tophys(r11,r11);						     \
-1:	subi	r11,r11,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
+1:	subi	r11,r11,INT_FRAME_SIZE;	/* Allocate an exception frame     */
+
+#define EXCEPTION_PROLOG_2						     \
 	stw	r10,_CCR(r11);          /* save various registers	   */\
 	stw	r12,GPR12(r11);						     \
 	stw	r9,GPR9(r11);						     \
@@ -205,7 +211,7 @@ label:
 
 #define EXCEPTION(n, label, hdlr, xfer)				\
 	START_EXCEPTION(n, label);				\
-	NORMAL_EXCEPTION_PROLOG;				\
+	EXCEPTION_PROLOG;				\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
 	xfer(n, hdlr)
 
@@ -396,7 +402,7 @@ label:
  * This is caused by a fetch from non-execute or guarded pages.
  */
 	START_EXCEPTION(0x0400, InstructionAccess)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mr	r4,r12			/* Pass SRR0 as arg2 */
 	li	r5,0			/* Pass zero as arg3 */
 	EXC_XFER_LITE(0x400, handle_page_fault)
@@ -406,7 +412,7 @@ label:
 
 /* 0x0600 - Alignment Exception */
 	START_EXCEPTION(0x0600, Alignment)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mfspr	r4,SPRN_DEAR		/* Grab the DEAR and save it */
 	stw	r4,_DEAR(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -414,7 +420,7 @@ label:
 
 /* 0x0700 - Program Exception */
 	START_EXCEPTION(0x0700, ProgramCheck)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mfspr	r4,SPRN_ESR		/* Grab the ESR and save it */
 	stw	r4,_ESR(r11)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -427,7 +433,7 @@ label:
 
 /* 0x0C00 - System Call Exception */
 	START_EXCEPTION(0x0C00,	SystemCall)
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	EXC_XFER_EE_LITE(0xc00, DoSyscall)
 
 	EXCEPTION(0x0D00, Trap_0D, unknown_exception, EXC_XFER_EE)
@@ -733,7 +739,7 @@ label:
 
 	/* Programmable Interval Timer (PIT) Exception. (from 0x1000) */
 Decrementer:
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	lis	r0,TSR_PIS@h
 	mtspr	SPRN_TSR,r0		/* Clear the PIT exception */
 	addi	r3,r1,STACK_FRAME_OVERHEAD
@@ -741,7 +747,7 @@ Decrementer:
 
 	/* Fixed Interval Timer (FIT) Exception. (from 0x1010) */
 FITException:
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	addi	r3,r1,STACK_FRAME_OVERHEAD;
 	EXC_XFER_EE(0x1010, unknown_exception)
 
@@ -759,7 +765,7 @@ WDTException:
  * if they can't resolve the lightweight TLB fault.
  */
 DataAccess:
-	NORMAL_EXCEPTION_PROLOG
+	EXCEPTION_PROLOG
 	mfspr	r5,SPRN_ESR		/* Grab the ESR, save it, pass arg3 */
 	stw	r5,_ESR(r11)
 	mfspr	r4,SPRN_DEAR		/* Grab the DEAR, save it, pass arg2 */
-- 
2.13.3

[PATCH 10/11] powerpc/40x: Add EXC_XFER_TEMPLATE_CRITICAL()

[Christophe Leroy]

This patch adds EXC_XFER_TEMPLATE_CRITICAL() for handling
transfer to critical exception handler. This will allow
to move the normal exception to using the standard
EXC_XFER_TEMPLATE() defined in head_32.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 1203075c0c1a..d52e460ea85e 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -219,9 +219,7 @@ label:
 	START_EXCEPTION(n, label);				\
 	CRITICAL_EXCEPTION_PROLOG;				\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
-	EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
-			  NOCOPY, crit_transfer_to_handler,	\
-			  ret_from_crit_exc)
+	EXC_XFER_TEMPLATE_CRITICAL(hdlr, n+2)
 
 #define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret)	\
 	li	r10,trap;					\
@@ -233,6 +231,14 @@ label:
 	.long	hdlr;						\
 	.long	ret
 
+#define EXC_XFER_TEMPLATE_CRITICAL(hdlr, trap)			\
+	li	r10,trap;					\
+	stw	r10,_TRAP(r11);					\
+	li	r10, MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE);	\
+	bl	crit_transfer_to_handler;		 	\
+	.long	hdlr;						\
+	.long	ret_from_crit_exc
+
 #define COPY_EE(d, s)		rlwimi d,s,0,16,16
 #define NOCOPY(d, s)
 
@@ -733,9 +739,7 @@ label:
 	/* continue normal handling for a critical exception... */
 2:	mfspr	r4,SPRN_DBSR
 	addi	r3,r1,STACK_FRAME_OVERHEAD
-	EXC_XFER_TEMPLATE(DebugException, 0x2002, \
-		(MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
-		NOCOPY, crit_transfer_to_handler, ret_from_crit_exc)
+	EXC_XFER_TEMPLATE_CRITICAL(DebugException, 0x2002)
 
 	/* Programmable Interval Timer (PIT) Exception. (from 0x1000) */
 Decrementer:
@@ -755,10 +759,7 @@ FITException:
 WDTException:
 	CRITICAL_EXCEPTION_PROLOG;
 	addi	r3,r1,STACK_FRAME_OVERHEAD;
-	EXC_XFER_TEMPLATE(WatchdogException, 0x1020+2,
-	                  (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)),
-			  NOCOPY, crit_transfer_to_handler,
-			  ret_from_crit_exc)
+	EXC_XFER_TEMPLATE_CRITICAL(WatchdogException, 0x1020+2)
 
 /*
  * The other Data TLB exceptions bail out to this point
-- 
2.13.3

[PATCH 11/11] powerpc/40x: Refactor exception entry macros by using head_32.h

[Christophe Leroy]

Refactor exception entry macros by using the ones defined in head_32.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/kernel/head_40x.S | 94 ++++--------------------------------------
 1 file changed, 8 insertions(+), 86 deletions(-)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index d52e460ea85e..e123bb3aff96 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -44,6 +44,14 @@
 #include <asm/export.h>
 #include <asm/asm-405.h>
 
+.macro DO_KVM intno
+.endm
+
+/* clear MSR_WE (necessary?)*/
+#define CLR_MSR_WE(reg)		rlwinm	reg, reg, 0, ~MSR_WE
+
+#include "head_32.h"
+
 /* As with the other PowerPC ports, it is expected that when code
  * execution begins here, the following registers contain valid, yet
  * optional, information:
@@ -99,52 +107,6 @@ _ENTRY(saved_ksp_limit)
 	.space	4
 
 /*
- * Exception vector entry code. This code runs with address translation
- * turned off (i.e. using physical addresses). We assume SPRG_THREAD has
- * the physical address of the current task thread_struct.
- */
-#define EXCEPTION_PROLOG						     \
-	mtspr	SPRN_SPRG_SCRATCH0,r10;	/* save two registers to work with */\
-	mtspr	SPRN_SPRG_SCRATCH1,r11;					     \
-	mfcr	r10;			/* save CR in r10 for now	   */\
-	EXCEPTION_PROLOG_1;						     \
-	EXCEPTION_PROLOG_2
-
-#define EXCEPTION_PROLOG_1						     \
-	mfspr	r11,SPRN_SRR1;		/* check whether user or kernel    */\
-	andi.	r11,r11,MSR_PR;						     \
-	tophys(r11,r1);							     \
-	beq	1f;							     \
-	mfspr	r11,SPRN_SPRG_THREAD;	/* if from user, start at top of   */\
-	lwz	r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
-	addi	r11,r11,THREAD_SIZE;					     \
-	tophys(r11,r11);						     \
-1:	subi	r11,r11,INT_FRAME_SIZE;	/* Allocate an exception frame     */
-
-#define EXCEPTION_PROLOG_2						     \
-	stw	r10,_CCR(r11);          /* save various registers	   */\
-	stw	r12,GPR12(r11);						     \
-	stw	r9,GPR9(r11);						     \
-	mfspr	r10,SPRN_SPRG_SCRATCH0;					     \
-	stw	r10,GPR10(r11);						     \
-	mfspr	r12,SPRN_SPRG_SCRATCH1;					     \
-	stw	r12,GPR11(r11);						     \
-	mflr	r10;							     \
-	stw	r10,_LINK(r11);						     \
-	mfspr	r12,SPRN_SRR0;						     \
-	stw	r1,GPR1(r11);						     \
-	mfspr	r9,SPRN_SRR1;						     \
-	stw	r1,0(r11);						     \
-	tovirt(r1,r11);			/* set new kernel sp */	\
-	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\
-	stw	r0,GPR0(r11);						     \
-	lis	r10, STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */\
-	addi	r10, r10, STACK_FRAME_REGS_MARKER@l;			     \
-	stw	r10, 8(r11);						     \
-	SAVE_4GPRS(3, r11);						     \
-	SAVE_2GPRS(7, r11)
-
-/*
  * Exception prolog for critical exceptions.  This is a little different
  * from the normal exception prolog above since a critical exception
  * can potentially occur at any point during normal exception processing.
@@ -205,32 +167,12 @@ _ENTRY(saved_ksp_limit)
 /*
  * Exception vectors.
  */
-#define	START_EXCEPTION(n, label)					     \
-	. = n;								     \
-label:
-
-#define EXCEPTION(n, label, hdlr, xfer)				\
-	START_EXCEPTION(n, label);				\
-	EXCEPTION_PROLOG;				\
-	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
-	xfer(n, hdlr)
-
 #define CRITICAL_EXCEPTION(n, label, hdlr)			\
 	START_EXCEPTION(n, label);				\
 	CRITICAL_EXCEPTION_PROLOG;				\
 	addi	r3,r1,STACK_FRAME_OVERHEAD;			\
 	EXC_XFER_TEMPLATE_CRITICAL(hdlr, n+2)
 
-#define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret)	\
-	li	r10,trap;					\
-	stw	r10,_TRAP(r11);					\
-	lis	r10,msr@h;					\
-	ori	r10,r10,msr@l;					\
-	copyee(r10, r9);					\
-	bl	tfer;		 				\
-	.long	hdlr;						\
-	.long	ret
-
 #define EXC_XFER_TEMPLATE_CRITICAL(hdlr, trap)			\
 	li	r10,trap;					\
 	stw	r10,_TRAP(r11);					\
@@ -239,26 +181,6 @@ label:
 	.long	hdlr;						\
 	.long	ret_from_crit_exc
 
-#define COPY_EE(d, s)		rlwimi d,s,0,16,16
-#define NOCOPY(d, s)
-
-#define EXC_XFER_STD(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_LITE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
-			  ret_from_except)
-
-#define EXC_XFER_EE(n, hdlr)		\
-	EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
-			  ret_from_except_full)
-
-#define EXC_XFER_EE_LITE(n, hdlr)	\
-	EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
-			  ret_from_except)
-
-
 /*
  * 0x0100 - Critical Interrupt Exception
  */
-- 
2.13.3

Re: [PATCH 00/11] Refactor exception entry on 40x/6xx/8xx

[Christoph Hellwig]

On Mon, Jan 28, 2019 at 11:11:10AM +0000, Christophe Leroy wrote:
> This serie refactors exception entry macros for 40x, 6xx and 8xx
> 
> This serie will benefit to the implementation of CONFIG_VMAP, and also
> to Ben's serie on MSR_EE.

We don't have a CONFIG_VMAP.  Do you mean CONFIG_VMAP_STACK ?

Re: [PATCH 00/11] Refactor exception entry on 40x/6xx/8xx

[Christophe Leroy]

Le 28/01/2019 à 15:15, Christoph Hellwig a écrit :
> On Mon, Jan 28, 2019 at 11:11:10AM +0000, Christophe Leroy wrote:
>> This serie refactors exception entry macros for 40x, 6xx and 8xx
>>
>> This serie will benefit to the implementation of CONFIG_VMAP, and also
>> to Ben's serie on MSR_EE.
> 
> We don't have a CONFIG_VMAP.  Do you mean CONFIG_VMAP_STACK ?
> 

Yes that's what I mean, sorry.