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
* is necessary since the MMU is always on, for Book-E parts, and the stacks
* are offset from KERNELBASE.
*
+ * There is some space optimization to be had here if desired. However
+ * to allow for a common kernel with support for debug exceptions either
+ * going to critical or their own debug level we aren't currently
+ * providing configurations that micro-optimize space usage.
*/
-#define BOOKE_EXCEPTION_STACK_SIZE (8192)
/* 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 - 4096)
+#define DEBUG_STACK_BASE dbgirq_ctx
#define DEBUG_SPRG SPRN_SPRG6W
+#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
/*
#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 */\
* save (and later restore) the MSR via SPRN_CSRR1, which will still have
* the MSR_DE bit set.
*/
-#ifdef CONFIG_E200
-#define DEBUG_EXCEPTION \
- START_EXCEPTION(Debug); \
+#define DEBUG_DEBUG_EXCEPTION \
+ START_EXCEPTION(DebugDebug); \
DEBUG_EXCEPTION_PROLOG; \
\
/* \
* 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; \
cmplw r12,r10; \
blt+ 2f; /* addr below exception vectors */ \
\
- lis r10,Debug@h; \
- ori r10,r10,Debug@l; \
+ lis r10,DebugDebug@h; \
+ ori r10,r10,DebugDebug@l; \
cmplw r12,r10; \
bgt+ 2f; /* addr above exception vectors */ \
\
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)
-#else
-#define DEBUG_EXCEPTION \
- START_EXCEPTION(Debug); \
+ 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); \
CRITICAL_EXCEPTION_PROLOG; \
\
/* \
cmplw r12,r10; \
blt+ 2f; /* addr below exception vectors */ \
\
- lis r10,Debug@h; \
- ori r10,r10,Debug@l; \
+ lis r10,DebugCrit@h; \
+ ori r10,r10,DebugCrit@l; \
cmplw r12,r10; \
bgt+ 2f; /* addr above exception vectors */ \
\
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; \
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)
-#endif
#define INSTRUCTION_STORAGE_EXCEPTION \
START_EXCEPTION(InstructionStorage) \
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__ */