*
* On 40x critical is the only additional level
* On 44x/e500 we have critical and machine check
+ * On e200 we have critical and debug (machine check occurs via critical)
*
* Additionally we reserve a SPRG for each priority level so we can free up a
* GPR to use as the base for indirect access to the exception stacks. This
/* CRIT_SPRG only used in critical exception handling */
#define CRIT_SPRG SPRN_SPRG2
-/* MCHECK_SPRG only used in critical exception handling */
+/* 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)
+/* only on e200 for now */
+#define DEBUG_STACK_TOP (exception_stack_top - 4096)
+#define DEBUG_SPRG SPRN_SPRG6W
+
#ifdef CONFIG_SMP
-#define BOOKE_LOAD_CRIT_STACK \
+#define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
mfspr r8,SPRN_PIR; \
mulli r8,r8,BOOKE_EXCEPTION_STACK_SIZE; \
neg r8,r8; \
- addis r8,r8,CRIT_STACK_TOP@ha; \
- addi r8,r8,CRIT_STACK_TOP@l
-#define BOOKE_LOAD_MCHECK_STACK \
- mfspr r8,SPRN_PIR; \
- mulli r8,r8,BOOKE_EXCEPTION_STACK_SIZE; \
- neg r8,r8; \
- addis r8,r8,MCHECK_STACK_TOP@ha; \
- addi r8,r8,MCHECK_STACK_TOP@l
+ addis r8,r8,level##_STACK_TOP@ha; \
+ addi r8,r8,level##_STACK_TOP@l
#else
-#define BOOKE_LOAD_CRIT_STACK \
- lis r8,CRIT_STACK_TOP@h; \
- ori r8,r8,CRIT_STACK_TOP@l
-#define BOOKE_LOAD_MCHECK_STACK \
- lis r8,MCHECK_STACK_TOP@h; \
- ori r8,r8,MCHECK_STACK_TOP@l
+#define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
+ lis r8,level##_STACK_TOP@h; \
+ ori r8,r8,level##_STACK_TOP@l
#endif
/*
- * 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.
- * Thus we cannot use the same SPRG registers as the normal prolog above.
- * Instead we use a portion of the critical exception stack at low physical
- * addresses.
+ * Exception prolog for critical/machine check exceptions. This is a
+ * little different from the normal exception prolog above since a
+ * critical/machine check exception can potentially occur at any point
+ * during normal exception processing. Thus we cannot use the same SPRG
+ * registers as the normal prolog above. Instead we use a portion of the
+ * critical/machine check exception stack at low physical addresses.
*/
-
-#define CRITICAL_EXCEPTION_PROLOG \
- mtspr CRIT_SPRG,r8; \
- BOOKE_LOAD_CRIT_STACK; /* r8 points to the crit stack */ \
+#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,SPRN_CSRR1; /* check whether user or kernel */\
+ mfspr r11,exc_level_srr1; /* check whether user or kernel */\
andi. r11,r11,MSR_PR; \
mr r11,r8; \
- mfspr r8,CRIT_SPRG; \
+ mfspr r8,exc_level##_SPRG; \
beq 1f; \
/* COMING FROM USER MODE */ \
mfspr r11,SPRN_SPRG3; /* if from user, start at top of */\
stw r12,_DEAR(r11); /* since they may have had stuff */\
mfspr r9,SPRN_ESR; /* in them at the point where the */\
stw r9,_ESR(r11); /* exception was taken */\
- mfspr r12,SPRN_CSRR0; \
+ mfspr r12,exc_level_srr0; \
stw r1,GPR1(r11); \
- mfspr r9,SPRN_CSRR1; \
+ mfspr r9,exc_level_srr1; \
stw r1,0(r11); \
mr r1,r11; \
rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
SAVE_4GPRS(3, r11); \
SAVE_2GPRS(7, r11)
-/*
- * Exception prolog for machine check exceptions. This is similar to
- * the critical exception prolog, except that machine check exceptions
- * have their stack.
- */
-#define MCHECK_EXCEPTION_PROLOG \
- mtspr MCHECK_SPRG,r8; \
- BOOKE_LOAD_MCHECK_STACK; /* r8 points to the mcheck 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,SPRN_MCSRR1; /* check whether user or kernel */\
- andi. r11,r11,MSR_PR; \
- mr r11,r8; \
- mfspr r8,MCHECK_SPRG; \
- beq 1f; \
- /* COMING FROM USER MODE */ \
- 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); \
- stw r9,GPR9(r11); \
- mflr r10; \
- stw r10,_LINK(r11); \
- mfspr r12,SPRN_DEAR; /* save DEAR and ESR in the frame */\
- stw r12,_DEAR(r11); /* since they may have had stuff */\
- mfspr r9,SPRN_ESR; /* in them at the point where the */\
- stw r9,_ESR(r11); /* exception was taken */\
- mfspr r12,SPRN_MCSRR0; \
- stw r1,GPR1(r11); \
- mfspr r9,SPRN_MCSRR1; \
- stw r1,0(r11); \
- mr r1,r11; \
- rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
- stw r0,GPR0(r11); \
- SAVE_4GPRS(3, r11); \
- SAVE_2GPRS(7, r11)
+#define CRITICAL_EXCEPTION_PROLOG \
+ EXC_LEVEL_EXCEPTION_PROLOG(CRIT, SPRN_CSRR0, SPRN_CSRR1)
+#define DEBUG_EXCEPTION_PROLOG \
+ EXC_LEVEL_EXCEPTION_PROLOG(DEBUG, SPRN_DSRR0, SPRN_DSRR1)
+#define MCHECK_EXCEPTION_PROLOG \
+ EXC_LEVEL_EXCEPTION_PROLOG(MCHECK, SPRN_MCSRR0, SPRN_MCSRR1)
/*
* Exception vectors.
EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
ret_from_except)
-
/* Check for a single step debug exception while in an exception
* handler before state has been saved. This is to catch the case
* where an instruction that we are trying to single step causes
* 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); \
+ DEBUG_EXCEPTION_PROLOG; \
+ \
+ /* \
+ * If there is a single step or branch-taken exception in an \
+ * exception entry sequence, it was probably meant to apply to \
+ * 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. \
+ */ \
+ mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
+ andis. r10,r10,DBSR_IC@h; \
+ beq+ 2f; \
+ \
+ lis r10,KERNELBASE@h; /* check if exception in vectors */ \
+ ori r10,r10,KERNELBASE@l; \
+ cmplw r12,r10; \
+ blt+ 2f; /* addr below exception vectors */ \
+ \
+ lis r10,Debug@h; \
+ ori r10,r10,Debug@l; \
+ cmplw r12,r10; \
+ bgt+ 2f; /* addr above exception vectors */ \
+ \
+ /* here it looks like we got an inappropriate debug exception. */ \
+1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CDRR1 value */ \
+ lis r10,DBSR_IC@h; /* clear the IC event */ \
+ mtspr SPRN_DBSR,r10; \
+ /* restore state and get out */ \
+ lwz r10,_CCR(r11); \
+ lwz r0,GPR0(r11); \
+ lwz r1,GPR1(r11); \
+ mtcrf 0x80,r10; \
+ mtspr SPRN_DSRR0,r12; \
+ mtspr SPRN_DSRR1,r9; \
+ lwz r9,GPR9(r11); \
+ 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); \
+ mfspr r8,DEBUG_SPRG; \
+ \
+ RFDI; \
+ b .; \
+ \
+ /* 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, debug_transfer_to_handler, ret_from_debug_exc)
+#else
#define DEBUG_EXCEPTION \
START_EXCEPTION(Debug); \
CRITICAL_EXCEPTION_PROLOG; \
lwz r9,GPR9(r11); \
lwz r12,GPR12(r11); \
mtspr CRIT_SPRG,r8; \
- BOOKE_LOAD_CRIT_STACK; /* r8 points to the crit stack */ \
+ 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); \
mfspr r8,CRIT_SPRG; \
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) \
mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \
stw r4,_DEAR(r11); \
addi r3,r1,STACK_FRAME_OVERHEAD; \
- EXC_XFER_EE(0x0600, AlignmentException)
+ EXC_XFER_EE(0x0600, alignment_exception)
#define PROGRAM_EXCEPTION \
START_EXCEPTION(Program) \
mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \
stw r4,_ESR(r11); \
addi r3,r1,STACK_FRAME_OVERHEAD; \
- EXC_XFER_STD(0x0700, ProgramCheckException)
+ EXC_XFER_STD(0x0700, program_check_exception)
#define DECREMENTER_EXCEPTION \
START_EXCEPTION(Decrementer) \
NORMAL_EXCEPTION_PROLOG; \
bne load_up_fpu; /* if from user, just load it up */ \
addi r3,r1,STACK_FRAME_OVERHEAD; \
- EXC_XFER_EE_LITE(0x800, KernelFP)
+ EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
#endif /* __HEAD_BOOKE_H__ */
git://git.onelab.eu / linux-2.6.git / blobdiff