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Diffstat (limited to 'arch/powerpc/kernel/exceptions-64s.S')
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 978 |
1 files changed, 978 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S new file mode 100644 index 000000000000..eb898112e577 --- /dev/null +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -0,0 +1,978 @@ +/* + * This file contains the 64-bit "server" PowerPC variant + * of the low level exception handling including exception + * vectors, exception return, part of the slb and stab + * handling and other fixed offset specific things. + * + * This file is meant to be #included from head_64.S due to + * position dependant assembly. + * + * Most of this originates from head_64.S and thus has the same + * copyright history. + * + */ + +/* + * We layout physical memory as follows: + * 0x0000 - 0x00ff : Secondary processor spin code + * 0x0100 - 0x2fff : pSeries Interrupt prologs + * 0x3000 - 0x5fff : interrupt support, iSeries and common interrupt prologs + * 0x6000 - 0x6fff : Initial (CPU0) segment table + * 0x7000 - 0x7fff : FWNMI data area + * 0x8000 - : Early init and support code + */ + + +/* + * SPRG Usage + * + * Register Definition + * + * SPRG0 reserved for hypervisor + * SPRG1 temp - used to save gpr + * SPRG2 temp - used to save gpr + * SPRG3 virt addr of paca + */ + +/* + * This is the start of the interrupt handlers for pSeries + * This code runs with relocation off. + * Code from here to __end_interrupts gets copied down to real + * address 0x100 when we are running a relocatable kernel. + * Therefore any relative branches in this section must only + * branch to labels in this section. + */ + . = 0x100 + .globl __start_interrupts +__start_interrupts: + + STD_EXCEPTION_PSERIES(0x100, system_reset) + + . = 0x200 +_machine_check_pSeries: + HMT_MEDIUM + mtspr SPRN_SPRG1,r13 /* save r13 */ + EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common) + + . = 0x300 + .globl data_access_pSeries +data_access_pSeries: + HMT_MEDIUM + mtspr SPRN_SPRG1,r13 +BEGIN_FTR_SECTION + mtspr SPRN_SPRG2,r12 + mfspr r13,SPRN_DAR + mfspr r12,SPRN_DSISR + srdi r13,r13,60 + rlwimi r13,r12,16,0x20 + mfcr r12 + cmpwi r13,0x2c + beq do_stab_bolted_pSeries + mtcrf 0x80,r12 + mfspr r12,SPRN_SPRG2 +END_FTR_SECTION_IFCLR(CPU_FTR_SLB) + EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common) + + . = 0x380 + .globl data_access_slb_pSeries +data_access_slb_pSeries: + HMT_MEDIUM + mtspr SPRN_SPRG1,r13 + mfspr r13,SPRN_SPRG3 /* get paca address into r13 */ + std r3,PACA_EXSLB+EX_R3(r13) + mfspr r3,SPRN_DAR + std r9,PACA_EXSLB+EX_R9(r13) /* save r9 - r12 */ + mfcr r9 +#ifdef __DISABLED__ + /* Keep that around for when we re-implement dynamic VSIDs */ + cmpdi r3,0 + bge slb_miss_user_pseries +#endif /* __DISABLED__ */ + std r10,PACA_EXSLB+EX_R10(r13) + std r11,PACA_EXSLB+EX_R11(r13) + std r12,PACA_EXSLB+EX_R12(r13) + mfspr r10,SPRN_SPRG1 + std r10,PACA_EXSLB+EX_R13(r13) + mfspr r12,SPRN_SRR1 /* and SRR1 */ +#ifndef CONFIG_RELOCATABLE + b .slb_miss_realmode +#else + /* + * We can't just use a direct branch to .slb_miss_realmode + * because the distance from here to there depends on where + * the kernel ends up being put. + */ + mfctr r11 + ld r10,PACAKBASE(r13) + LOAD_HANDLER(r10, .slb_miss_realmode) + mtctr r10 + bctr +#endif + + STD_EXCEPTION_PSERIES(0x400, instruction_access) + + . = 0x480 + .globl instruction_access_slb_pSeries +instruction_access_slb_pSeries: + HMT_MEDIUM + mtspr SPRN_SPRG1,r13 + mfspr r13,SPRN_SPRG3 /* get paca address into r13 */ + std r3,PACA_EXSLB+EX_R3(r13) + mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */ + std r9,PACA_EXSLB+EX_R9(r13) /* save r9 - r12 */ + mfcr r9 +#ifdef __DISABLED__ + /* Keep that around for when we re-implement dynamic VSIDs */ + cmpdi r3,0 + bge slb_miss_user_pseries +#endif /* __DISABLED__ */ + std r10,PACA_EXSLB+EX_R10(r13) + std r11,PACA_EXSLB+EX_R11(r13) + std r12,PACA_EXSLB+EX_R12(r13) + mfspr r10,SPRN_SPRG1 + std r10,PACA_EXSLB+EX_R13(r13) + mfspr r12,SPRN_SRR1 /* and SRR1 */ +#ifndef CONFIG_RELOCATABLE + b .slb_miss_realmode +#else + mfctr r11 + ld r10,PACAKBASE(r13) + LOAD_HANDLER(r10, .slb_miss_realmode) + mtctr r10 + bctr +#endif + + MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt) + STD_EXCEPTION_PSERIES(0x600, alignment) + STD_EXCEPTION_PSERIES(0x700, program_check) + STD_EXCEPTION_PSERIES(0x800, fp_unavailable) + MASKABLE_EXCEPTION_PSERIES(0x900, decrementer) + STD_EXCEPTION_PSERIES(0xa00, trap_0a) + STD_EXCEPTION_PSERIES(0xb00, trap_0b) + + . = 0xc00 + .globl system_call_pSeries +system_call_pSeries: + HMT_MEDIUM +BEGIN_FTR_SECTION + cmpdi r0,0x1ebe + beq- 1f +END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) + mr r9,r13 + mfspr r13,SPRN_SPRG3 + mfspr r11,SPRN_SRR0 + ld r12,PACAKBASE(r13) + ld r10,PACAKMSR(r13) + LOAD_HANDLER(r12, system_call_entry) + mtspr SPRN_SRR0,r12 + mfspr r12,SPRN_SRR1 + mtspr SPRN_SRR1,r10 + rfid + b . /* prevent speculative execution */ + +/* Fast LE/BE switch system call */ +1: mfspr r12,SPRN_SRR1 + xori r12,r12,MSR_LE + mtspr SPRN_SRR1,r12 + rfid /* return to userspace */ + b . + + STD_EXCEPTION_PSERIES(0xd00, single_step) + STD_EXCEPTION_PSERIES(0xe00, trap_0e) + + /* We need to deal with the Altivec unavailable exception + * here which is at 0xf20, thus in the middle of the + * prolog code of the PerformanceMonitor one. A little + * trickery is thus necessary + */ + . = 0xf00 + b performance_monitor_pSeries + + . = 0xf20 + b altivec_unavailable_pSeries + + . = 0xf40 + b vsx_unavailable_pSeries + +#ifdef CONFIG_CBE_RAS + HSTD_EXCEPTION_PSERIES(0x1200, cbe_system_error) +#endif /* CONFIG_CBE_RAS */ + STD_EXCEPTION_PSERIES(0x1300, instruction_breakpoint) +#ifdef CONFIG_CBE_RAS + HSTD_EXCEPTION_PSERIES(0x1600, cbe_maintenance) +#endif /* CONFIG_CBE_RAS */ + STD_EXCEPTION_PSERIES(0x1700, altivec_assist) +#ifdef CONFIG_CBE_RAS + HSTD_EXCEPTION_PSERIES(0x1800, cbe_thermal) +#endif /* CONFIG_CBE_RAS */ + + . = 0x3000 + +/*** pSeries interrupt support ***/ + + /* moved from 0xf00 */ + STD_EXCEPTION_PSERIES(., performance_monitor) + STD_EXCEPTION_PSERIES(., altivec_unavailable) + STD_EXCEPTION_PSERIES(., vsx_unavailable) + +/* + * An interrupt came in while soft-disabled; clear EE in SRR1, + * clear paca->hard_enabled and return. + */ +masked_interrupt: + stb r10,PACAHARDIRQEN(r13) + mtcrf 0x80,r9 + ld r9,PACA_EXGEN+EX_R9(r13) + mfspr r10,SPRN_SRR1 + rldicl r10,r10,48,1 /* clear MSR_EE */ + rotldi r10,r10,16 + mtspr SPRN_SRR1,r10 + ld r10,PACA_EXGEN+EX_R10(r13) + mfspr r13,SPRN_SPRG1 + rfid + b . + + .align 7 +do_stab_bolted_pSeries: + mtcrf 0x80,r12 + mfspr r12,SPRN_SPRG2 + EXCEPTION_PROLOG_PSERIES(PACA_EXSLB, .do_stab_bolted) + +#ifdef CONFIG_PPC_PSERIES +/* + * Vectors for the FWNMI option. Share common code. + */ + .globl system_reset_fwnmi + .align 7 +system_reset_fwnmi: + HMT_MEDIUM + mtspr SPRN_SPRG1,r13 /* save r13 */ + EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common) + + .globl machine_check_fwnmi + .align 7 +machine_check_fwnmi: + HMT_MEDIUM + mtspr SPRN_SPRG1,r13 /* save r13 */ + EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common) + +#endif /* CONFIG_PPC_PSERIES */ + +#ifdef __DISABLED__ +/* + * This is used for when the SLB miss handler has to go virtual, + * which doesn't happen for now anymore but will once we re-implement + * dynamic VSIDs for shared page tables + */ +slb_miss_user_pseries: + std r10,PACA_EXGEN+EX_R10(r13) + std r11,PACA_EXGEN+EX_R11(r13) + std r12,PACA_EXGEN+EX_R12(r13) + mfspr r10,SPRG1 + ld r11,PACA_EXSLB+EX_R9(r13) + ld r12,PACA_EXSLB+EX_R3(r13) + std r10,PACA_EXGEN+EX_R13(r13) + std r11,PACA_EXGEN+EX_R9(r13) + std r12,PACA_EXGEN+EX_R3(r13) + clrrdi r12,r13,32 + mfmsr r10 + mfspr r11,SRR0 /* save SRR0 */ + ori r12,r12,slb_miss_user_common@l /* virt addr of handler */ + ori r10,r10,MSR_IR|MSR_DR|MSR_RI + mtspr SRR0,r12 + mfspr r12,SRR1 /* and SRR1 */ + mtspr SRR1,r10 + rfid + b . /* prevent spec. execution */ +#endif /* __DISABLED__ */ + + .align 7 + .globl __end_interrupts +__end_interrupts: + +/* + * Code from here down to __end_handlers is invoked from the + * exception prologs above. Because the prologs assemble the + * addresses of these handlers using the LOAD_HANDLER macro, + * which uses an addi instruction, these handlers must be in + * the first 32k of the kernel image. + */ + +/*** Common interrupt handlers ***/ + + STD_EXCEPTION_COMMON(0x100, system_reset, .system_reset_exception) + + /* + * Machine check is different because we use a different + * save area: PACA_EXMC instead of PACA_EXGEN. + */ + .align 7 + .globl machine_check_common +machine_check_common: + EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC) + FINISH_NAP + DISABLE_INTS + bl .save_nvgprs + addi r3,r1,STACK_FRAME_OVERHEAD + bl .machine_check_exception + b .ret_from_except + + STD_EXCEPTION_COMMON_LITE(0x900, decrementer, .timer_interrupt) + STD_EXCEPTION_COMMON(0xa00, trap_0a, .unknown_exception) + STD_EXCEPTION_COMMON(0xb00, trap_0b, .unknown_exception) + STD_EXCEPTION_COMMON(0xd00, single_step, .single_step_exception) + STD_EXCEPTION_COMMON(0xe00, trap_0e, .unknown_exception) + STD_EXCEPTION_COMMON_IDLE(0xf00, performance_monitor, .performance_monitor_exception) + STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, .instruction_breakpoint_exception) +#ifdef CONFIG_ALTIVEC + STD_EXCEPTION_COMMON(0x1700, altivec_assist, .altivec_assist_exception) +#else + STD_EXCEPTION_COMMON(0x1700, altivec_assist, .unknown_exception) +#endif +#ifdef CONFIG_CBE_RAS + STD_EXCEPTION_COMMON(0x1200, cbe_system_error, .cbe_system_error_exception) + STD_EXCEPTION_COMMON(0x1600, cbe_maintenance, .cbe_maintenance_exception) + STD_EXCEPTION_COMMON(0x1800, cbe_thermal, .cbe_thermal_exception) +#endif /* CONFIG_CBE_RAS */ + + .align 7 +system_call_entry: + b system_call_common + +/* + * Here we have detected that the kernel stack pointer is bad. + * R9 contains the saved CR, r13 points to the paca, + * r10 contains the (bad) kernel stack pointer, + * r11 and r12 contain the saved SRR0 and SRR1. + * We switch to using an emergency stack, save the registers there, + * and call kernel_bad_stack(), which panics. + */ +bad_stack: + ld r1,PACAEMERGSP(r13) + subi r1,r1,64+INT_FRAME_SIZE + std r9,_CCR(r1) + std r10,GPR1(r1) + std r11,_NIP(r1) + std r12,_MSR(r1) + mfspr r11,SPRN_DAR + mfspr r12,SPRN_DSISR + std r11,_DAR(r1) + std r12,_DSISR(r1) + mflr r10 + mfctr r11 + mfxer r12 + std r10,_LINK(r1) + std r11,_CTR(r1) + std r12,_XER(r1) + SAVE_GPR(0,r1) + SAVE_GPR(2,r1) + SAVE_4GPRS(3,r1) + SAVE_2GPRS(7,r1) + SAVE_10GPRS(12,r1) + SAVE_10GPRS(22,r1) + lhz r12,PACA_TRAP_SAVE(r13) + std r12,_TRAP(r1) + addi r11,r1,INT_FRAME_SIZE + std r11,0(r1) + li r12,0 + std r12,0(r11) + ld r2,PACATOC(r13) +1: addi r3,r1,STACK_FRAME_OVERHEAD + bl .kernel_bad_stack + b 1b + +/* + * Here r13 points to the paca, r9 contains the saved CR, + * SRR0 and SRR1 are saved in r11 and r12, + * r9 - r13 are saved in paca->exgen. + */ + .align 7 + .globl data_access_common +data_access_common: + mfspr r10,SPRN_DAR + std r10,PACA_EXGEN+EX_DAR(r13) + mfspr r10,SPRN_DSISR + stw r10,PACA_EXGEN+EX_DSISR(r13) + EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN) + ld r3,PACA_EXGEN+EX_DAR(r13) + lwz r4,PACA_EXGEN+EX_DSISR(r13) + li r5,0x300 + b .do_hash_page /* Try to handle as hpte fault */ + + .align 7 + .globl instruction_access_common +instruction_access_common: + EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN) + ld r3,_NIP(r1) + andis. r4,r12,0x5820 + li r5,0x400 + b .do_hash_page /* Try to handle as hpte fault */ + +/* + * Here is the common SLB miss user that is used when going to virtual + * mode for SLB misses, that is currently not used + */ +#ifdef __DISABLED__ + .align 7 + .globl slb_miss_user_common +slb_miss_user_common: + mflr r10 + std r3,PACA_EXGEN+EX_DAR(r13) + stw r9,PACA_EXGEN+EX_CCR(r13) + std r10,PACA_EXGEN+EX_LR(r13) + std r11,PACA_EXGEN+EX_SRR0(r13) + bl .slb_allocate_user + + ld r10,PACA_EXGEN+EX_LR(r13) + ld r3,PACA_EXGEN+EX_R3(r13) + lwz r9,PACA_EXGEN+EX_CCR(r13) + ld r11,PACA_EXGEN+EX_SRR0(r13) + mtlr r10 + beq- slb_miss_fault + + andi. r10,r12,MSR_RI /* check for unrecoverable exception */ + beq- unrecov_user_slb + mfmsr r10 + +.machine push +.machine "power4" + mtcrf 0x80,r9 +.machine pop + + clrrdi r10,r10,2 /* clear RI before setting SRR0/1 */ + mtmsrd r10,1 + + mtspr SRR0,r11 + mtspr SRR1,r12 + + ld r9,PACA_EXGEN+EX_R9(r13) + ld r10,PACA_EXGEN+EX_R10(r13) + ld r11,PACA_EXGEN+EX_R11(r13) + ld r12,PACA_EXGEN+EX_R12(r13) + ld r13,PACA_EXGEN+EX_R13(r13) + rfid + b . + +slb_miss_fault: + EXCEPTION_PROLOG_COMMON(0x380, PACA_EXGEN) + ld r4,PACA_EXGEN+EX_DAR(r13) + li r5,0 + std r4,_DAR(r1) + std r5,_DSISR(r1) + b handle_page_fault + +unrecov_user_slb: + EXCEPTION_PROLOG_COMMON(0x4200, PACA_EXGEN) + DISABLE_INTS + bl .save_nvgprs +1: addi r3,r1,STACK_FRAME_OVERHEAD + bl .unrecoverable_exception + b 1b + +#endif /* __DISABLED__ */ + + +/* + * r13 points to the PACA, r9 contains the saved CR, + * r12 contain the saved SRR1, SRR0 is still ready for return + * r3 has the faulting address + * r9 - r13 are saved in paca->exslb. + * r3 is saved in paca->slb_r3 + * We assume we aren't going to take any exceptions during this procedure. + */ +_GLOBAL(slb_miss_realmode) + mflr r10 +#ifdef CONFIG_RELOCATABLE + mtctr r11 +#endif + + stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */ + std r10,PACA_EXSLB+EX_LR(r13) /* save LR */ + + bl .slb_allocate_realmode + + /* All done -- return from exception. */ + + ld r10,PACA_EXSLB+EX_LR(r13) + ld r3,PACA_EXSLB+EX_R3(r13) + lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */ +#ifdef CONFIG_PPC_ISERIES +BEGIN_FW_FTR_SECTION + ld r11,PACALPPACAPTR(r13) + ld r11,LPPACASRR0(r11) /* get SRR0 value */ +END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES) +#endif /* CONFIG_PPC_ISERIES */ + + mtlr r10 + + andi. r10,r12,MSR_RI /* check for unrecoverable exception */ + beq- 2f + +.machine push +.machine "power4" + mtcrf 0x80,r9 + mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */ +.machine pop + +#ifdef CONFIG_PPC_ISERIES +BEGIN_FW_FTR_SECTION + mtspr SPRN_SRR0,r11 + mtspr SPRN_SRR1,r12 +END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES) +#endif /* CONFIG_PPC_ISERIES */ + ld r9,PACA_EXSLB+EX_R9(r13) + ld r10,PACA_EXSLB+EX_R10(r13) + ld r11,PACA_EXSLB+EX_R11(r13) + ld r12,PACA_EXSLB+EX_R12(r13) + ld r13,PACA_EXSLB+EX_R13(r13) + rfid + b . /* prevent speculative execution */ + +2: +#ifdef CONFIG_PPC_ISERIES +BEGIN_FW_FTR_SECTION + b unrecov_slb +END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES) +#endif /* CONFIG_PPC_ISERIES */ + mfspr r11,SPRN_SRR0 + ld r10,PACAKBASE(r13) + LOAD_HANDLER(r10,unrecov_slb) + mtspr SPRN_SRR0,r10 + ld r10,PACAKMSR(r13) + mtspr SPRN_SRR1,r10 + rfid + b . + +unrecov_slb: + EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB) + DISABLE_INTS + bl .save_nvgprs +1: addi r3,r1,STACK_FRAME_OVERHEAD + bl .unrecoverable_exception + b 1b + + .align 7 + .globl hardware_interrupt_common + .globl hardware_interrupt_entry +hardware_interrupt_common: + EXCEPTION_PROLOG_COMMON(0x500, PACA_EXGEN) + FINISH_NAP +hardware_interrupt_entry: + DISABLE_INTS +BEGIN_FTR_SECTION + bl .ppc64_runlatch_on +END_FTR_SECTION_IFSET(CPU_FTR_CTRL) + addi r3,r1,STACK_FRAME_OVERHEAD + bl .do_IRQ + b .ret_from_except_lite + +#ifdef CONFIG_PPC_970_NAP +power4_fixup_nap: + andc r9,r9,r10 + std r9,TI_LOCAL_FLAGS(r11) + ld r10,_LINK(r1) /* make idle task do the */ + std r10,_NIP(r1) /* equivalent of a blr */ + blr +#endif + + .align 7 + .globl alignment_common +alignment_common: + mfspr r10,SPRN_DAR + std r10,PACA_EXGEN+EX_DAR(r13) + mfspr r10,SPRN_DSISR + stw r10,PACA_EXGEN+EX_DSISR(r13) + EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN) + ld r3,PACA_EXGEN+EX_DAR(r13) + lwz r4,PACA_EXGEN+EX_DSISR(r13) + std r3,_DAR(r1) + std r4,_DSISR(r1) + bl .save_nvgprs + addi r3,r1,STACK_FRAME_OVERHEAD + ENABLE_INTS + bl .alignment_exception + b .ret_from_except + + .align 7 + .globl program_check_common +program_check_common: + EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN) + bl .save_nvgprs + addi r3,r1,STACK_FRAME_OVERHEAD + ENABLE_INTS + bl .program_check_exception + b .ret_from_except + + .align 7 + .globl fp_unavailable_common +fp_unavailable_common: + EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN) + bne 1f /* if from user, just load it up */ + bl .save_nvgprs + addi r3,r1,STACK_FRAME_OVERHEAD + ENABLE_INTS + bl .kernel_fp_unavailable_exception + BUG_OPCODE +1: bl .load_up_fpu + b fast_exception_return + + .align 7 + .globl altivec_unavailable_common +altivec_unavailable_common: + EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN) +#ifdef CONFIG_ALTIVEC +BEGIN_FTR_SECTION + beq 1f + bl .load_up_altivec + b fast_exception_return +1: +END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) +#endif + bl .save_nvgprs + addi r3,r1,STACK_FRAME_OVERHEAD + ENABLE_INTS + bl .altivec_unavailable_exception + b .ret_from_except + + .align 7 + .globl vsx_unavailable_common +vsx_unavailable_common: + EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN) +#ifdef CONFIG_VSX +BEGIN_FTR_SECTION + bne .load_up_vsx +1: +END_FTR_SECTION_IFSET(CPU_FTR_VSX) +#endif + bl .save_nvgprs + addi r3,r1,STACK_FRAME_OVERHEAD + ENABLE_INTS + bl .vsx_unavailable_exception + b .ret_from_except + + .align 7 + .globl __end_handlers +__end_handlers: + +/* + * Return from an exception with minimal checks. + * The caller is assumed to have done EXCEPTION_PROLOG_COMMON. + * If interrupts have been enabled, or anything has been + * done that might have changed the scheduling status of + * any task or sent any task a signal, you should use + * ret_from_except or ret_from_except_lite instead of this. + */ +fast_exc_return_irq: /* restores irq state too */ + ld r3,SOFTE(r1) + TRACE_AND_RESTORE_IRQ(r3); + ld r12,_MSR(r1) + rldicl r4,r12,49,63 /* get MSR_EE to LSB */ + stb r4,PACAHARDIRQEN(r13) /* restore paca->hard_enabled */ + b 1f + + .globl fast_exception_return +fast_exception_return: + ld r12,_MSR(r1) +1: ld r11,_NIP(r1) + andi. r3,r12,MSR_RI /* check if RI is set */ + beq- unrecov_fer + +#ifdef CONFIG_VIRT_CPU_ACCOUNTING + andi. r3,r12,MSR_PR + beq 2f + ACCOUNT_CPU_USER_EXIT(r3, r4) +2: +#endif + + ld r3,_CCR(r1) + ld r4,_LINK(r1) + ld r5,_CTR(r1) + ld r6,_XER(r1) + mtcr r3 + mtlr r4 + mtctr r5 + mtxer r6 + REST_GPR(0, r1) + REST_8GPRS(2, r1) + + mfmsr r10 + rldicl r10,r10,48,1 /* clear EE */ + rldicr r10,r10,16,61 /* clear RI (LE is 0 already) */ + mtmsrd r10,1 + + mtspr SPRN_SRR1,r12 + mtspr SPRN_SRR0,r11 + REST_4GPRS(10, r1) + ld r1,GPR1(r1) + rfid + b . /* prevent speculative execution */ + +unrecov_fer: + bl .save_nvgprs +1: addi r3,r1,STACK_FRAME_OVERHEAD + bl .unrecoverable_exception + b 1b + + +/* + * Hash table stuff + */ + .align 7 +_STATIC(do_hash_page) + std r3,_DAR(r1) + std r4,_DSISR(r1) + + andis. r0,r4,0xa450 /* weird error? */ + bne- handle_page_fault /* if not, try to insert a HPTE */ +BEGIN_FTR_SECTION + andis. r0,r4,0x0020 /* Is it a segment table fault? */ + bne- do_ste_alloc /* If so handle it */ +END_FTR_SECTION_IFCLR(CPU_FTR_SLB) + + /* + * On iSeries, we soft-disable interrupts here, then + * hard-enable interrupts so that the hash_page code can spin on + * the hash_table_lock without problems on a shared processor. + */ + DISABLE_INTS + + /* + * Currently, trace_hardirqs_off() will be called by DISABLE_INTS + * and will clobber volatile registers when irq tracing is enabled + * so we need to reload them. It may be possible to be smarter here + * and move the irq tracing elsewhere but let's keep it simple for + * now + */ +#ifdef CONFIG_TRACE_IRQFLAGS + ld r3,_DAR(r1) + ld r4,_DSISR(r1) + ld r5,_TRAP(r1) + ld r12,_MSR(r1) + clrrdi r5,r5,4 +#endif /* CONFIG_TRACE_IRQFLAGS */ + /* + * We need to set the _PAGE_USER bit if MSR_PR is set or if we are + * accessing a userspace segment (even from the kernel). We assume + * kernel addresses always have the high bit set. + */ + rlwinm r4,r4,32-25+9,31-9,31-9 /* DSISR_STORE -> _PAGE_RW */ + rotldi r0,r3,15 /* Move high bit into MSR_PR posn */ + orc r0,r12,r0 /* MSR_PR | ~high_bit */ + rlwimi r4,r0,32-13,30,30 /* becomes _PAGE_USER access bit */ + ori r4,r4,1 /* add _PAGE_PRESENT */ + rlwimi r4,r5,22+2,31-2,31-2 /* Set _PAGE_EXEC if trap is 0x400 */ + + /* + * r3 contains the faulting address + * r4 contains the required access permissions + * r5 contains the trap number + * + * at return r3 = 0 for success + */ + bl .hash_page /* build HPTE if possible */ + cmpdi r3,0 /* see if hash_page succeeded */ + +BEGIN_FW_FTR_SECTION + /* + * If we had interrupts soft-enabled at the point where the + * DSI/ISI occurred, and an interrupt came in during hash_page, + * handle it now. + * We jump to ret_from_except_lite rather than fast_exception_return + * because ret_from_except_lite will check for and handle pending + * interrupts if necessary. + */ + beq 13f +END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES) + +BEGIN_FW_FTR_SECTION + /* + * Here we have interrupts hard-disabled, so it is sufficient + * to restore paca->{soft,hard}_enable and get out. + */ + beq fast_exc_return_irq /* Return from exception on success */ +END_FW_FTR_SECTION_IFCLR(FW_FEATURE_ISERIES) + + /* For a hash failure, we don't bother re-enabling interrupts */ + ble- 12f + + /* + * hash_page couldn't handle it, set soft interrupt enable back + * to what it was before the trap. Note that .raw_local_irq_restore + * handles any interrupts pending at this point. + */ + ld r3,SOFTE(r1) + TRACE_AND_RESTORE_IRQ_PARTIAL(r3, 11f) + bl .raw_local_irq_restore + b 11f + +/* Here we have a page fault that hash_page can't handle. */ +handle_page_fault: + ENABLE_INTS +11: ld r4,_DAR(r1) + ld r5,_DSISR(r1) + addi r3,r1,STACK_FRAME_OVERHEAD + bl .do_page_fault + cmpdi r3,0 + beq+ 13f + bl .save_nvgprs + mr r5,r3 + addi r3,r1,STACK_FRAME_OVERHEAD + lwz r4,_DAR(r1) + bl .bad_page_fault + b .ret_from_except + +13: b .ret_from_except_lite + +/* We have a page fault that hash_page could handle but HV refused + * the PTE insertion + */ +12: bl .save_nvgprs + mr r5,r3 + addi r3,r1,STACK_FRAME_OVERHEAD + ld r4,_DAR(r1) + bl .low_hash_fault + b .ret_from_except + + /* here we have a segment miss */ +do_ste_alloc: + bl .ste_allocate /* try to insert stab entry */ + cmpdi r3,0 + bne- handle_page_fault + b fast_exception_return + +/* + * r13 points to the PACA, r9 contains the saved CR, + * r11 and r12 contain the saved SRR0 and SRR1. + * r9 - r13 are saved in paca->exslb. + * We assume we aren't going to take any exceptions during this procedure. + * We assume (DAR >> 60) == 0xc. + */ + .align 7 +_GLOBAL(do_stab_bolted) + stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */ + std r11,PACA_EXSLB+EX_SRR0(r13) /* save SRR0 in exc. frame */ + + /* Hash to the primary group */ + ld r10,PACASTABVIRT(r13) + mfspr r11,SPRN_DAR + srdi r11,r11,28 + rldimi r10,r11,7,52 /* r10 = first ste of the group */ + + /* Calculate VSID */ + /* This is a kernel address, so protovsid = ESID */ + ASM_VSID_SCRAMBLE(r11, r9, 256M) + rldic r9,r11,12,16 /* r9 = vsid << 12 */ + + /* Search the primary group for a free entry */ +1: ld r11,0(r10) /* Test valid bit of the current ste */ + andi. r11,r11,0x80 + beq 2f + addi r10,r10,16 + andi. r11,r10,0x70 + bne 1b + + /* Stick for only searching the primary group for now. */ + /* At least for now, we use a very simple random castout scheme */ + /* Use the TB as a random number ; OR in 1 to avoid entry 0 */ + mftb r11 + rldic r11,r11,4,57 /* r11 = (r11 << 4) & 0x70 */ + ori r11,r11,0x10 + + /* r10 currently points to an ste one past the group of interest */ + /* make it point to the randomly selected entry */ + subi r10,r10,128 + or r10,r10,r11 /* r10 is the entry to invalidate */ + + isync /* mark the entry invalid */ + ld r11,0(r10) + rldicl r11,r11,56,1 /* clear the valid bit */ + rotldi r11,r11,8 + std r11,0(r10) + sync + + clrrdi r11,r11,28 /* Get the esid part of the ste */ + slbie r11 + +2: std r9,8(r10) /* Store the vsid part of the ste */ + eieio + + mfspr r11,SPRN_DAR /* Get the new esid */ + clrrdi r11,r11,28 /* Permits a full 32b of ESID */ + ori r11,r11,0x90 /* Turn on valid and kp */ + std r11,0(r10) /* Put new entry back into the stab */ + + sync + + /* All done -- return from exception. */ + lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */ + ld r11,PACA_EXSLB+EX_SRR0(r13) /* get saved SRR0 */ + + andi. r10,r12,MSR_RI + beq- unrecov_slb + + mtcrf 0x80,r9 /* restore CR */ + + mfmsr r10 + clrrdi r10,r10,2 + mtmsrd r10,1 + + mtspr SPRN_SRR0,r11 + mtspr SPRN_SRR1,r12 + ld r9,PACA_EXSLB+EX_R9(r13) + ld r10,PACA_EXSLB+EX_R10(r13) + ld r11,PACA_EXSLB+EX_R11(r13) + ld r12,PACA_EXSLB+EX_R12(r13) + ld r13,PACA_EXSLB+EX_R13(r13) + rfid + b . /* prevent speculative execution */ + +/* + * Space for CPU0's segment table. + * + * On iSeries, the hypervisor must fill in at least one entry before + * we get control (with relocate on). The address is given to the hv + * as a page number (see xLparMap below), so this must be at a + * fixed address (the linker can't compute (u64)&initial_stab >> + * PAGE_SHIFT). + */ + . = STAB0_OFFSET /* 0x6000 */ + .globl initial_stab +initial_stab: + .space 4096 + +#ifdef CONFIG_PPC_PSERIES +/* + * Data area reserved for FWNMI option. + * This address (0x7000) is fixed by the RPA. + */ + .= 0x7000 + .globl fwnmi_data_area +fwnmi_data_area: +#endif /* CONFIG_PPC_PSERIES */ + + /* iSeries does not use the FWNMI stuff, so it is safe to put + * this here, even if we later allow kernels that will boot on + * both pSeries and iSeries */ +#ifdef CONFIG_PPC_ISERIES + . = LPARMAP_PHYS + .globl xLparMap +xLparMap: + .quad HvEsidsToMap /* xNumberEsids */ + .quad HvRangesToMap /* xNumberRanges */ + .quad STAB0_PAGE /* xSegmentTableOffs */ + .zero 40 /* xRsvd */ + /* xEsids (HvEsidsToMap entries of 2 quads) */ + .quad PAGE_OFFSET_ESID /* xKernelEsid */ + .quad PAGE_OFFSET_VSID /* xKernelVsid */ + .quad VMALLOC_START_ESID /* xKernelEsid */ + .quad VMALLOC_START_VSID /* xKernelVsid */ + /* xRanges (HvRangesToMap entries of 3 quads) */ + .quad HvPagesToMap /* xPages */ + .quad 0 /* xOffset */ + .quad PAGE_OFFSET_VSID << (SID_SHIFT - HW_PAGE_SHIFT) /* xVPN */ + +#endif /* CONFIG_PPC_ISERIES */ + +#ifdef CONFIG_PPC_PSERIES + . = 0x8000 +#endif /* CONFIG_PPC_PSERIES */ |