diff options
Diffstat (limited to 'arch/ppc/kernel/head_booke.h')
| -rw-r--r-- | arch/ppc/kernel/head_booke.h | 64 |
1 files changed, 63 insertions, 1 deletions
diff --git a/arch/ppc/kernel/head_booke.h b/arch/ppc/kernel/head_booke.h index 9c50f9d2657c..9342acf12e72 100644 --- a/arch/ppc/kernel/head_booke.h +++ b/arch/ppc/kernel/head_booke.h @@ -49,6 +49,7 @@ * * 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 @@ -60,12 +61,16 @@ /* 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_EXC_LEVEL_STACK(level) \ mfspr r8,SPRN_PIR; \ @@ -124,6 +129,8 @@ #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) @@ -205,6 +212,60 @@ label: * 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; \ @@ -257,6 +318,7 @@ label: 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) \ |