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Diffstat (limited to 'arch/powerpc/kernel/head_booke.h')
| -rw-r--r-- | arch/powerpc/kernel/head_booke.h | 527 |
1 files changed, 527 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h new file mode 100644 index 000000000..b6b5b01a1 --- /dev/null +++ b/arch/powerpc/kernel/head_booke.h @@ -0,0 +1,527 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __HEAD_BOOKE_H__ +#define __HEAD_BOOKE_H__ + +#include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */ +#include <asm/kvm_asm.h> +#include <asm/kvm_booke_hv_asm.h> +#include <asm/thread_info.h> /* 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 40x and Book-E + * processors we allocate a stack per additional priority level. + * + * 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. + * + * 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__ */ |