diff options
Diffstat (limited to 'arch/powerpc/kernel/head_booke.h')
| -rw-r--r-- | arch/powerpc/kernel/head_booke.h | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h new file mode 100644 index 000000000000..8536e7676160 --- /dev/null +++ b/arch/powerpc/kernel/head_booke.h @@ -0,0 +1,363 @@ +#ifndef __HEAD_BOOKE_H__ +#define __HEAD_BOOKE_H__ + +/* + * Macros used for common Book-e exception handling + */ + +#define SET_IVOR(vector_number, vector_label) \ + li r26,vector_label@l; \ + mtspr SPRN_IVOR##vector_number,r26; \ + sync + +#define NORMAL_EXCEPTION_PROLOG \ + mtspr SPRN_SPRG0,r10; /* save two registers to work with */\ + mtspr SPRN_SPRG1,r11; \ + mtspr SPRN_SPRG4W,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_SPRG3; /* if from user, start at top of */\ + lwz r1,THREAD_INFO-THREAD(r1); /* this thread's kernel stack */\ + addi r1,r1,THREAD_SIZE; \ +1: subi r1,r1,INT_FRAME_SIZE; /* Allocate an exception frame */\ + mr r11,r1; \ + stw r10,_CCR(r11); /* save various registers */\ + stw r12,GPR12(r11); \ + stw r9,GPR9(r11); \ + mfspr r10,SPRN_SPRG0; \ + stw r10,GPR10(r11); \ + mfspr r12,SPRN_SPRG1; \ + stw r12,GPR11(r11); \ + mflr r10; \ + stw r10,_LINK(r11); \ + mfspr r10,SPRN_SPRG4R; \ + mfspr r12,SPRN_SRR0; \ + stw r10,GPR1(r11); \ + mfspr r9,SPRN_SRR1; \ + stw r10,0(r11); \ + rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\ + stw r0,GPR0(r11); \ + SAVE_4GPRS(3, r11); \ + 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 + * + * 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 + * is necessary since the MMU is always on, for Book-E parts, and the stacks + * are offset from KERNELBASE. + * + */ +#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) + +/* 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; \ + mulli r8,r8,BOOKE_EXCEPTION_STACK_SIZE; \ + neg r8,r8; \ + addis r8,r8,level##_STACK_TOP@ha; \ + addi r8,r8,level##_STACK_TOP@l +#else +#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/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 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 */ \ + 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,exc_level_srr0; \ + stw r1,GPR1(r11); \ + mfspr r9,exc_level_srr1; \ + 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. + */ +#define START_EXCEPTION(label) \ + .align 5; \ +label: + +#define FINISH_EXCEPTION(func) \ + bl transfer_to_handler_full; \ + .long func; \ + .long ret_from_except_full + +#define EXCEPTION(n, label, hdlr, xfer) \ + START_EXCEPTION(label); \ + NORMAL_EXCEPTION_PROLOG; \ + addi r3,r1,STACK_FRAME_OVERHEAD; \ + xfer(n, hdlr) + +#define CRITICAL_EXCEPTION(n, label, hdlr) \ + START_EXCEPTION(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) + +#define MCHECK_EXCEPTION(n, label, hdlr) \ + START_EXCEPTION(label); \ + MCHECK_EXCEPTION_PROLOG; \ + mfspr r5,SPRN_ESR; \ + stw r5,_ESR(r11); \ + addi r3,r1,STACK_FRAME_OVERHEAD; \ + EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \ + NOCOPY, mcheck_transfer_to_handler, \ + ret_from_mcheck_exc) + +#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 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) + +/* 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 + * an exception (eg ITLB/DTLB miss) and thus the first instruction of + * the exception handler generates a single step debug exception. + * + * If we get a debug trap on the first instruction of an exception handler, + * we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is + * a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR). + * The exception handler was handling a non-critical interrupt, so it will + * 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; \ + \ + /* \ + * 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 CSRR1 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_CSRR0,r12; \ + mtspr SPRN_CSRR1,r9; \ + lwz r9,GPR9(r11); \ + 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); \ + mfspr r8,CRIT_SPRG; \ + \ + rfci; \ + 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, crit_transfer_to_handler, ret_from_crit_exc) +#endif + +#define INSTRUCTION_STORAGE_EXCEPTION \ + START_EXCEPTION(InstructionStorage) \ + NORMAL_EXCEPTION_PROLOG; \ + mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \ + stw r5,_ESR(r11); \ + mr r4,r12; /* Pass SRR0 as arg2 */ \ + li r5,0; /* Pass zero as arg3 */ \ + EXC_XFER_EE_LITE(0x0400, handle_page_fault) + +#define ALIGNMENT_EXCEPTION \ + START_EXCEPTION(Alignment) \ + NORMAL_EXCEPTION_PROLOG; \ + mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \ + stw r4,_DEAR(r11); \ + addi r3,r1,STACK_FRAME_OVERHEAD; \ + EXC_XFER_EE(0x0600, alignment_exception) + +#define PROGRAM_EXCEPTION \ + START_EXCEPTION(Program) \ + NORMAL_EXCEPTION_PROLOG; \ + mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \ + stw r4,_ESR(r11); \ + addi r3,r1,STACK_FRAME_OVERHEAD; \ + EXC_XFER_STD(0x0700, program_check_exception) + +#define DECREMENTER_EXCEPTION \ + START_EXCEPTION(Decrementer) \ + NORMAL_EXCEPTION_PROLOG; \ + lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \ + mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \ + addi r3,r1,STACK_FRAME_OVERHEAD; \ + EXC_XFER_LITE(0x0900, timer_interrupt) + +#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; \ + EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception) + +#endif /* __HEAD_BOOKE_H__ */ |
