| #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 |
| * |
| * 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 critical exception handling */ |
| #define MCHECK_SPRG SPRN_SPRG6W |
| |
| #define MCHECK_STACK_TOP (exception_stack_top - 4096) |
| #define CRIT_STACK_TOP (exception_stack_top) |
| |
| #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 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. |
| */ |
| #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) |
| |
| #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, AlignmentException) |
| |
| #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, ProgramCheckException) |
| |
| #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, KernelFP) |
| |
| #endif /* __HEAD_BOOKE_H__ */ |