/* * 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. * */ #include /* * 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 */