--- /dev/null
+#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, KernelFP)
+
+#endif /* __HEAD_BOOKE_H__ */
git.openpandora.org / pandora-kernel.git / blobdiff