Merge branch 'linux-next' of git://git.infradead.org/~dedekind/ubi-2.6

1 files changed, 85 insertions, 41 deletions

diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index aefafc6330c9..fce2df988504 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -43,9 +43,7 @@
 	SAVE_2GPRS(7, r11)
 
 /* To handle the additional exception priority levels on 40x and Book-E
- * processors we allocate a 4k stack per additional priority level. The various
- * head_xxx.S files allocate space (exception_stack_top) for each priority's
- * stack times the number of CPUs
+ * processors we allocate a stack per additional priority level.
  *
  * On 40x critical is the only additional level
  * On 44x/e500 we have critical and machine check
@@ -61,36 +59,37 @@
  * going to critical or their own debug level we aren't currently
  * providing configurations that micro-optimize space usage.
  */
-#ifdef CONFIG_44x
-#define NUM_EXCEPTION_LVLS	2
-#else
-#define NUM_EXCEPTION_LVLS	3
-#endif
-#define BOOKE_EXCEPTION_STACK_SIZE	(4096 * NUM_EXCEPTION_LVLS)
 
 /* CRIT_SPRG only used in critical exception handling */
 #define CRIT_SPRG	SPRN_SPRG2
 /* MCHECK_SPRG only used in machine check exception handling */
 #define MCHECK_SPRG	SPRN_SPRG6W
 
-#define MCHECK_STACK_TOP	(exception_stack_top - 4096)
-#define CRIT_STACK_TOP		(exception_stack_top)
+#define MCHECK_STACK_BASE	mcheckirq_ctx
+#define CRIT_STACK_BASE		critirq_ctx
 
-/* only on e200 for now */
-#define DEBUG_STACK_TOP		(exception_stack_top - 8192)
+/* only on e500mc/e200 */
+#define DEBUG_STACK_BASE	dbgirq_ctx
+#ifdef CONFIG_PPC_E500MC
+#define DEBUG_SPRG		SPRN_SPRG9
+#else
 #define DEBUG_SPRG		SPRN_SPRG6W
+#endif
+
+#define EXC_LVL_FRAME_OVERHEAD	(THREAD_SIZE - INT_FRAME_SIZE - EXC_LVL_SIZE)
 
 #ifdef CONFIG_SMP
 #define BOOKE_LOAD_EXC_LEVEL_STACK(level)		\
 	mfspr	r8,SPRN_PIR;				\
-	mulli	r8,r8,BOOKE_EXCEPTION_STACK_SIZE;	\
-	neg	r8,r8;					\
-	addis	r8,r8,level##_STACK_TOP@ha;		\
-	addi	r8,r8,level##_STACK_TOP@l
+	slwi	r8,r8,2;				\
+	addis	r8,r8,level##_STACK_BASE@ha;		\
+	lwz	r8,level##_STACK_BASE@l(r8);		\
+	addi	r8,r8,EXC_LVL_FRAME_OVERHEAD;
 #else
 #define BOOKE_LOAD_EXC_LEVEL_STACK(level)		\
-	lis	r8,level##_STACK_TOP@h;			\
-	ori	r8,r8,level##_STACK_TOP@l
+	lis	r8,level##_STACK_BASE@ha;		\
+	lwz	r8,level##_STACK_BASE@l(r8);		\
+	addi	r8,r8,EXC_LVL_FRAME_OVERHEAD;
 #endif
 
 /*
@@ -104,22 +103,36 @@
 #define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, exc_level_srr0, exc_level_srr1) \
 	mtspr	exc_level##_SPRG,r8;					     \
 	BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \
-	stw	r10,GPR10-INT_FRAME_SIZE(r8);				     \
-	stw	r11,GPR11-INT_FRAME_SIZE(r8);				     \
-	mfcr	r10;			/* save CR in r10 for now	   */\
-	mfspr	r11,exc_level_srr1;	/* check whether user or kernel    */\
-	andi.	r11,r11,MSR_PR;						     \
-	mr	r11,r8;							     \
-	mfspr	r8,exc_level##_SPRG;					     \
-	beq	1f;							     \
-	/* COMING FROM USER MODE */					     \
+	stw	r9,GPR9(r8);		/* save various registers	   */\
+	mfcr	r9;			/* save CR in r9 for now	   */\
+	stw	r10,GPR10(r8);						     \
+	stw	r11,GPR11(r8);						     \
+	stw	r9,_CCR(r8);		/* save CR on stack		   */\
+	mfspr	r10,exc_level_srr1;	/* check whether user or kernel    */\
+	andi.	r10,r10,MSR_PR;						     \
 	mfspr	r11,SPRN_SPRG3;		/* if from user, start at top of   */\
 	lwz	r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
-	addi	r11,r11,THREAD_SIZE;					     \
-1:	subi	r11,r11,INT_FRAME_SIZE;	/* Allocate an exception frame     */\
-	stw	r10,_CCR(r11);          /* save various registers	   */\
-	stw	r12,GPR12(r11);						     \
+	addi	r11,r11,EXC_LVL_FRAME_OVERHEAD;	/* allocate stack frame    */\
+	beq	1f;							     \
+	/* COMING FROM USER MODE */					     \
+	stw	r9,_CCR(r11);		/* save CR			   */\
+	lwz	r10,GPR10(r8);		/* copy regs from exception stack  */\
+	lwz	r9,GPR9(r8);						     \
+	stw	r10,GPR10(r11);						     \
+	lwz	r10,GPR11(r8);						     \
 	stw	r9,GPR9(r11);						     \
+	stw	r10,GPR11(r11);						     \
+	b	2f;							     \
+	/* COMING FROM PRIV MODE */					     \
+1:	lwz	r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r11);		     \
+	lwz	r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r11);		     \
+	stw	r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r8);			     \
+	stw	r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r8);		     \
+	lwz	r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r11);			     \
+	stw	r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r8);			     \
+	mr	r11,r8;							     \
+2:	mfspr	r8,exc_level##_SPRG;					     \
+	stw	r12,GPR12(r11);		/* save various registers	   */\
 	mflr	r10;							     \
 	stw	r10,_LINK(r11);						     \
 	mfspr	r12,SPRN_DEAR;		/* save DEAR and ESR in the frame  */\
@@ -231,7 +244,7 @@ label:
 	 * the code where the exception occurred (since exception entry	      \
 	 * doesn't turn off DE automatically).  We simulate the effect	      \
 	 * of turning off DE on entry to an exception handler by turning      \
-	 * off DE in the CSRR1 value and clearing the debug status.	      \
+	 * off DE in the DSRR1 value and clearing the debug status.	      \
 	 */								      \
 	mfspr	r10,SPRN_DBSR;		/* check single-step/branch taken */  \
 	andis.	r10,r10,DBSR_IC@h;					      \
@@ -262,17 +275,17 @@ label:
 	lwz	r12,GPR12(r11);						      \
 	mtspr	DEBUG_SPRG,r8;						      \
 	BOOKE_LOAD_EXC_LEVEL_STACK(DEBUG); /* r8 points to the debug stack */ \
-	lwz	r10,GPR10-INT_FRAME_SIZE(r8);				      \
-	lwz	r11,GPR11-INT_FRAME_SIZE(r8);				      \
+	lwz	r10,GPR10(r8);						      \
+	lwz	r11,GPR11(r8);						      \
 	mfspr	r8,DEBUG_SPRG;						      \
 									      \
 	RFDI;								      \
 	b	.;							      \
 									      \
-	/* continue normal handling for a critical exception... */	      \
+	/* continue normal handling for a debug 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, debug_transfer_to_handler, ret_from_debug_exc)
+	EXC_XFER_TEMPLATE(DebugException, 0x2008, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, debug_transfer_to_handler, ret_from_debug_exc)
 
 #define DEBUG_CRIT_EXCEPTION						      \
 	START_EXCEPTION(DebugCrit);					      \
@@ -315,8 +328,8 @@ label:
 	lwz	r12,GPR12(r11);						      \
 	mtspr	CRIT_SPRG,r8;						      \
 	BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */  \
-	lwz	r10,GPR10-INT_FRAME_SIZE(r8);				      \
-	lwz	r11,GPR11-INT_FRAME_SIZE(r8);				      \
+	lwz	r10,GPR10(r8);						      \
+	lwz	r11,GPR11(r8);						      \
 	mfspr	r8,CRIT_SPRG;						      \
 									      \
 	rfci;								      \
@@ -327,6 +340,14 @@ label:
 	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)
 
+#define DATA_STORAGE_EXCEPTION						      \
+	START_EXCEPTION(DataStorage)					      \
+	NORMAL_EXCEPTION_PROLOG;					      \
+	mfspr	r5,SPRN_ESR;		/* Grab the ESR and save it */	      \
+	stw	r5,_ESR(r11);						      \
+	mfspr	r4,SPRN_DEAR;		/* Grab the DEAR */		      \
+	EXC_XFER_EE_LITE(0x0300, handle_page_fault)
+
 #define INSTRUCTION_STORAGE_EXCEPTION					      \
 	START_EXCEPTION(InstructionStorage)				      \
 	NORMAL_EXCEPTION_PROLOG;					      \
@@ -363,8 +384,31 @@ label:
 #define FP_UNAVAILABLE_EXCEPTION					      \
 	START_EXCEPTION(FloatingPointUnavailable)			      \
 	NORMAL_EXCEPTION_PROLOG;					      \
-	bne	load_up_fpu;		/* if from user, just load it up */   \
-	addi	r3,r1,STACK_FRAME_OVERHEAD;				      \
+	beq	1f;							      \
+	bl	load_up_fpu;		/* if from user, just load it up */   \
+	b	fast_exception_return;					      \
+1:	addi	r3,r1,STACK_FRAME_OVERHEAD;				      \
 	EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
 
+#ifndef __ASSEMBLY__
+struct exception_regs {
+	unsigned long mas0;
+	unsigned long mas1;
+	unsigned long mas2;
+	unsigned long mas3;
+	unsigned long mas6;
+	unsigned long mas7;
+	unsigned long srr0;
+	unsigned long srr1;
+	unsigned long csrr0;
+	unsigned long csrr1;
+	unsigned long dsrr0;
+	unsigned long dsrr1;
+	unsigned long saved_ksp_limit;
+};
+
+/* ensure this structure is always sized to a multiple of the stack alignment */
+#define STACK_EXC_LVL_FRAME_SIZE	_ALIGN_UP(sizeof (struct exception_regs), 16)
+
+#endif /* __ASSEMBLY__ */
 #endif /* __HEAD_BOOKE_H__ */