/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __HEAD_BOOKE_H__ #define __HEAD_BOOKE_H__ #include /* for STACK_FRAME_REGS_MARKER */ #include #include #include /* for THREAD_SHIFT */ #ifdef __ASSEMBLY__ /* * 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 #if (THREAD_SHIFT < 15) #define ALLOC_STACK_FRAME(reg, val) \ addi reg,reg,val #else #define ALLOC_STACK_FRAME(reg, val) \ addis reg,reg,val@ha; \ addi reg,reg,val@l #endif /* * Macro used to get to thread save registers. * Note that entries 0-3 are used for the prolog code, and the remaining * entries are available for specific exception use in the event a handler * requires more than 4 scratch registers. */ #define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4)) #ifdef CONFIG_PPC_E500 #define BOOKE_CLEAR_BTB(reg) \ START_BTB_FLUSH_SECTION \ BTB_FLUSH(reg) \ END_BTB_FLUSH_SECTION #else #define BOOKE_CLEAR_BTB(reg) #endif #define NORMAL_EXCEPTION_PROLOG(trapno, intno) \ mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \ mfspr r10, SPRN_SPRG_THREAD; \ stw r11, THREAD_NORMSAVE(0)(r10); \ stw r13, THREAD_NORMSAVE(2)(r10); \ mfcr r13; /* save CR in r13 for now */\ mfspr r11, SPRN_SRR1; \ DO_KVM BOOKE_INTERRUPT_##intno SPRN_SRR1; \ andi. r11, r11, MSR_PR; /* check whether user or kernel */\ LOAD_REG_IMMEDIATE(r11, MSR_KERNEL); \ mtmsr r11; \ mr r11, r1; \ beq 1f; \ BOOKE_CLEAR_BTB(r11) \ /* if from user, start at top of this thread's kernel stack */ \ lwz r11, TASK_STACK - THREAD(r10); \ ALLOC_STACK_FRAME(r11, THREAD_SIZE); \ 1 : subi r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */ \ stw r13, _CCR(r11); /* save various registers */ \ stw r12,GPR12(r11); \ stw r9,GPR9(r11); \ mfspr r13, SPRN_SPRG_RSCRATCH0; \ stw r13, GPR10(r11); \ lwz r12, THREAD_NORMSAVE(0)(r10); \ stw r12,GPR11(r11); \ lwz r13, THREAD_NORMSAVE(2)(r10); /* restore r13 */ \ mflr r10; \ stw r10,_LINK(r11); \ mfspr r12,SPRN_SRR0; \ stw r1, GPR1(r11); \ mfspr r9,SPRN_SRR1; \ stw r1, 0(r11); \ mr r1, r11; \ rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\ COMMON_EXCEPTION_PROLOG_END trapno .macro COMMON_EXCEPTION_PROLOG_END trapno stw r0,GPR0(r1) lis r10, STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ addi r10, r10, STACK_FRAME_REGS_MARKER@l stw r10, STACK_INT_FRAME_MARKER(r1) li r10, \trapno stw r10,_TRAP(r1) SAVE_GPRS(3, 8, r1) SAVE_NVGPRS(r1) stw r2,GPR2(r1) stw r12,_NIP(r1) stw r9,_MSR(r1) mfctr r10 mfspr r2,SPRN_SPRG_THREAD stw r10,_CTR(r1) tovirt(r2, r2) mfspr r10,SPRN_XER addi r2, r2, -THREAD stw r10,_XER(r1) addi r3,r1,STACK_INT_FRAME_REGS .endm .macro prepare_transfer_to_handler #ifdef CONFIG_PPC_E500 andi. r12,r9,MSR_PR bne 777f bl prepare_transfer_to_handler 777: #endif .endm .macro SYSCALL_ENTRY trapno intno srr1 mfspr r10, SPRN_SPRG_THREAD #ifdef CONFIG_KVM_BOOKE_HV BEGIN_FTR_SECTION mtspr SPRN_SPRG_WSCRATCH0, r10 stw r11, THREAD_NORMSAVE(0)(r10) stw r13, THREAD_NORMSAVE(2)(r10) mfcr r13 /* save CR in r13 for now */ mfspr r11, SPRN_SRR1 mtocrf 0x80, r11 /* check MSR[GS] without clobbering reg */ bf 3, 1975f b kvmppc_handler_\intno\()_\srr1 1975: mr r12, r13 lwz r13, THREAD_NORMSAVE(2)(r10) FTR_SECTION_ELSE mfcr r12 ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) #else mfcr r12 #endif mfspr r9, SPRN_SRR1 BOOKE_CLEAR_BTB(r11) mr r11, r1 lwz r1, TASK_STACK - THREAD(r10) rlwinm r12,r12,0,4,2 /* Clear SO bit in CR */ ALLOC_STACK_FRAME(r1, THREAD_SIZE - INT_FRAME_SIZE) stw r12, _CCR(r1) mfspr r12,SPRN_SRR0 stw r12,_NIP(r1) b transfer_to_syscall /* jump to handler */ .endm /* To handle the additional exception priority levels on Book-E * processors we allocate a stack per additional priority 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. * * There is some space optimization to be had here if desired. However * to allow for a common kernel with support for debug exceptions either * going to critical or their own debug level we aren't currently * providing configurations that micro-optimize space usage. */ #define MC_STACK_BASE mcheckirq_ctx #define CRIT_STACK_BASE critirq_ctx /* only on e500mc */ #define DBG_STACK_BASE dbgirq_ctx #ifdef CONFIG_SMP #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \ mfspr r8,SPRN_PIR; \ slwi r8,r8,2; \ addis r8,r8,level##_STACK_BASE@ha; \ lwz r8,level##_STACK_BASE@l(r8); \ addi r8,r8,THREAD_SIZE - INT_FRAME_SIZE; #else #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \ lis r8,level##_STACK_BASE@ha; \ lwz r8,level##_STACK_BASE@l(r8); \ addi r8,r8,THREAD_SIZE - INT_FRAME_SIZE; #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, trapno, intno, exc_level_srr0, exc_level_srr1) \ mtspr SPRN_SPRG_WSCRATCH_##exc_level,r8; \ BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \ stw r9,GPR9(r8); /* save various registers */\ mfcr r9; /* save CR in r9 for now */\ stw r10,GPR10(r8); \ stw r11,GPR11(r8); \ stw r9,_CCR(r8); /* save CR on stack */\ mfspr r11,exc_level_srr1; /* check whether user or kernel */\ DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \ BOOKE_CLEAR_BTB(r10) \ andi. r11,r11,MSR_PR; \ LOAD_REG_IMMEDIATE(r11, MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)); \ mtmsr r11; \ mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\ lwz r11, TASK_STACK - THREAD(r11); /* this thread's kernel stack */\ addi r11,r11,THREAD_SIZE - INT_FRAME_SIZE; /* allocate stack frame */\ beq 1f; \ /* COMING FROM USER MODE */ \ stw r9,_CCR(r11); /* save CR */\ lwz r10,GPR10(r8); /* copy regs from exception stack */\ lwz r9,GPR9(r8); \ stw r10,GPR10(r11); \ lwz r10,GPR11(r8); \ stw r9,GPR9(r11); \ stw r10,GPR11(r11); \ b 2f; \ /* COMING FROM PRIV MODE */ \ 1: mr r11, r8; \ 2: mfspr r8,SPRN_SPRG_RSCRATCH_##exc_level; \ stw r12,GPR12(r11); /* save various registers */\ 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?) */\ COMMON_EXCEPTION_PROLOG_END trapno #define SAVE_xSRR(xSRR) \ mfspr r0,SPRN_##xSRR##0; \ stw r0,_##xSRR##0(r1); \ mfspr r0,SPRN_##xSRR##1; \ stw r0,_##xSRR##1(r1) .macro SAVE_MMU_REGS #ifdef CONFIG_PPC_E500 mfspr r0,SPRN_MAS0 stw r0,MAS0(r1) mfspr r0,SPRN_MAS1 stw r0,MAS1(r1) mfspr r0,SPRN_MAS2 stw r0,MAS2(r1) mfspr r0,SPRN_MAS3 stw r0,MAS3(r1) mfspr r0,SPRN_MAS6 stw r0,MAS6(r1) #ifdef CONFIG_PHYS_64BIT mfspr r0,SPRN_MAS7 stw r0,MAS7(r1) #endif /* CONFIG_PHYS_64BIT */ #endif /* CONFIG_PPC_E500 */ #ifdef CONFIG_44x mfspr r0,SPRN_MMUCR stw r0,MMUCR(r1) #endif .endm #define CRITICAL_EXCEPTION_PROLOG(trapno, intno) \ EXC_LEVEL_EXCEPTION_PROLOG(CRIT, trapno+2, intno, SPRN_CSRR0, SPRN_CSRR1) #define DEBUG_EXCEPTION_PROLOG(trapno) \ EXC_LEVEL_EXCEPTION_PROLOG(DBG, trapno+8, DEBUG, SPRN_DSRR0, SPRN_DSRR1) #define MCHECK_EXCEPTION_PROLOG(trapno) \ EXC_LEVEL_EXCEPTION_PROLOG(MC, trapno+4, MACHINE_CHECK, \ SPRN_MCSRR0, SPRN_MCSRR1) /* * Guest Doorbell -- this is a bit odd in that uses GSRR0/1 despite * being delivered to the host. This exception can only happen * inside a KVM guest -- so we just handle up to the DO_KVM rather * than try to fit this into one of the existing prolog macros. */ #define GUEST_DOORBELL_EXCEPTION \ START_EXCEPTION(GuestDoorbell); \ mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \ mfspr r10, SPRN_SPRG_THREAD; \ stw r11, THREAD_NORMSAVE(0)(r10); \ mfspr r11, SPRN_SRR1; \ stw r13, THREAD_NORMSAVE(2)(r10); \ mfcr r13; /* save CR in r13 for now */\ DO_KVM BOOKE_INTERRUPT_GUEST_DBELL SPRN_GSRR1; \ trap /* * Exception vectors. */ #define START_EXCEPTION(label) \ .align 5; \ label: #define EXCEPTION(n, intno, label, hdlr) \ START_EXCEPTION(label); \ NORMAL_EXCEPTION_PROLOG(n, intno); \ prepare_transfer_to_handler; \ bl hdlr; \ b interrupt_return #define CRITICAL_EXCEPTION(n, intno, label, hdlr) \ START_EXCEPTION(label); \ CRITICAL_EXCEPTION_PROLOG(n, intno); \ SAVE_MMU_REGS; \ SAVE_xSRR(SRR); \ prepare_transfer_to_handler; \ bl hdlr; \ b ret_from_crit_exc #define MCHECK_EXCEPTION(n, label, hdlr) \ START_EXCEPTION(label); \ MCHECK_EXCEPTION_PROLOG(n); \ mfspr r5,SPRN_ESR; \ stw r5,_ESR(r11); \ SAVE_xSRR(DSRR); \ SAVE_xSRR(CSRR); \ SAVE_MMU_REGS; \ SAVE_xSRR(SRR); \ prepare_transfer_to_handler; \ bl hdlr; \ b ret_from_mcheck_exc /* 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_DEBUG_EXCEPTION \ START_EXCEPTION(DebugDebug); \ DEBUG_EXCEPTION_PROLOG(2000); \ \ /* \ * 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 DSRR1 value and clearing the debug status. \ */ \ mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \ andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \ beq+ 2f; \ \ lis r10,interrupt_base@h; /* check if exception in vectors */ \ ori r10,r10,interrupt_base@l; \ cmplw r12,r10; \ blt+ 2f; /* addr below exception vectors */ \ \ lis r10,interrupt_end@h; \ ori r10,r10,interrupt_end@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|DBSR_BT)@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 SPRN_SPRG_WSCRATCH_DBG,r8; \ BOOKE_LOAD_EXC_LEVEL_STACK(DBG); /* r8 points to the debug stack */ \ lwz r10,GPR10(r8); \ lwz r11,GPR11(r8); \ mfspr r8,SPRN_SPRG_RSCRATCH_DBG; \ \ PPC_RFDI; \ b .; \ \ /* continue normal handling for a debug exception... */ \ 2: mfspr r4,SPRN_DBSR; \ stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\ SAVE_xSRR(CSRR); \ SAVE_MMU_REGS; \ SAVE_xSRR(SRR); \ prepare_transfer_to_handler; \ bl DebugException; \ b ret_from_debug_exc #define DEBUG_CRIT_EXCEPTION \ START_EXCEPTION(DebugCrit); \ CRITICAL_EXCEPTION_PROLOG(2000,DEBUG); \ \ /* \ * 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|DBSR_BT)@h; \ beq+ 2f; \ \ lis r10,interrupt_base@h; /* check if exception in vectors */ \ ori r10,r10,interrupt_base@l; \ cmplw r12,r10; \ blt+ 2f; /* addr below exception vectors */ \ \ lis r10,interrupt_end@h; \ ori r10,r10,interrupt_end@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|DBSR_BT)@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 SPRN_SPRG_WSCRATCH_CRIT,r8; \ BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */ \ lwz r10,GPR10(r8); \ lwz r11,GPR11(r8); \ mfspr r8,SPRN_SPRG_RSCRATCH_CRIT; \ \ rfci; \ b .; \ \ /* continue normal handling for a critical exception... */ \ 2: mfspr r4,SPRN_DBSR; \ stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\ SAVE_MMU_REGS; \ SAVE_xSRR(SRR); \ prepare_transfer_to_handler; \ bl DebugException; \ b ret_from_crit_exc #define DATA_STORAGE_EXCEPTION \ START_EXCEPTION(DataStorage) \ NORMAL_EXCEPTION_PROLOG(0x300, DATA_STORAGE); \ mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \ stw r5,_ESR(r11); \ mfspr r4,SPRN_DEAR; /* Grab the DEAR */ \ stw r4, _DEAR(r11); \ prepare_transfer_to_handler; \ bl do_page_fault; \ b interrupt_return /* * Instruction TLB Error interrupt handlers may call InstructionStorage * directly without clearing ESR, so the ESR at this point may be left over * from a prior interrupt. * * In any case, do_page_fault for BOOK3E does not use ESR and always expects * dsisr to be 0. ESR_DST from a prior store in particular would confuse fault * handling. */ #define INSTRUCTION_STORAGE_EXCEPTION \ START_EXCEPTION(InstructionStorage) \ NORMAL_EXCEPTION_PROLOG(0x400, INST_STORAGE); \ li r5,0; /* Store 0 in regs->esr (dsisr) */ \ stw r5,_ESR(r11); \ stw r12, _DEAR(r11); /* Set regs->dear (dar) to SRR0 */ \ prepare_transfer_to_handler; \ bl do_page_fault; \ b interrupt_return #define ALIGNMENT_EXCEPTION \ START_EXCEPTION(Alignment) \ NORMAL_EXCEPTION_PROLOG(0x600, ALIGNMENT); \ mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \ stw r4,_DEAR(r11); \ prepare_transfer_to_handler; \ bl alignment_exception; \ REST_NVGPRS(r1); \ b interrupt_return #define PROGRAM_EXCEPTION \ START_EXCEPTION(Program) \ NORMAL_EXCEPTION_PROLOG(0x700, PROGRAM); \ mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \ stw r4,_ESR(r11); \ prepare_transfer_to_handler; \ bl program_check_exception; \ REST_NVGPRS(r1); \ b interrupt_return #define DECREMENTER_EXCEPTION \ START_EXCEPTION(Decrementer) \ NORMAL_EXCEPTION_PROLOG(0x900, DECREMENTER); \ lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \ mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \ prepare_transfer_to_handler; \ bl timer_interrupt; \ b interrupt_return #define FP_UNAVAILABLE_EXCEPTION \ START_EXCEPTION(FloatingPointUnavailable) \ NORMAL_EXCEPTION_PROLOG(0x800, FP_UNAVAIL); \ beq 1f; \ bl load_up_fpu; /* if from user, just load it up */ \ b fast_exception_return; \ 1: prepare_transfer_to_handler; \ bl kernel_fp_unavailable_exception; \ b interrupt_return #endif /* __ASSEMBLY__ */ #endif /* __HEAD_BOOKE_H__ */