/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * PowerPC version * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP * Copyright (C) 1996 Cort Dougan * Adapted for Power Macintosh by Paul Mackerras. * Low-level exception handlers and MMU support * rewritten by Paul Mackerras. * Copyright (C) 1996 Paul Mackerras. * MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net). * * This file contains the low-level support and setup for the * PowerPC platform, including trap and interrupt dispatch. * (The PPC 8xx embedded CPUs use head_8xx.S instead.) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "head_32.h" #define LOAD_BAT(n, reg, RA, RB) \ /* see the comment for clear_bats() -- Cort */ \ li RA,0; \ mtspr SPRN_IBAT##n##U,RA; \ mtspr SPRN_DBAT##n##U,RA; \ lwz RA,(n*16)+0(reg); \ lwz RB,(n*16)+4(reg); \ mtspr SPRN_IBAT##n##U,RA; \ mtspr SPRN_IBAT##n##L,RB; \ lwz RA,(n*16)+8(reg); \ lwz RB,(n*16)+12(reg); \ mtspr SPRN_DBAT##n##U,RA; \ mtspr SPRN_DBAT##n##L,RB __HEAD .stabs "arch/powerpc/kernel/",N_SO,0,0,0f .stabs "head_book3s_32.S",N_SO,0,0,0f 0: _ENTRY(_stext); /* * _start is defined this way because the XCOFF loader in the OpenFirmware * on the powermac expects the entry point to be a procedure descriptor. */ _ENTRY(_start); /* * These are here for legacy reasons, the kernel used to * need to look like a coff function entry for the pmac * but we're always started by some kind of bootloader now. * -- Cort */ nop /* used by __secondary_hold on prep (mtx) and chrp smp */ nop /* used by __secondary_hold on prep (mtx) and chrp smp */ nop /* PMAC * Enter here with the kernel text, data and bss loaded starting at * 0, running with virtual == physical mapping. * r5 points to the prom entry point (the client interface handler * address). Address translation is turned on, with the prom * managing the hash table. Interrupts are disabled. The stack * pointer (r1) points to just below the end of the half-meg region * from 0x380000 - 0x400000, which is mapped in already. * * If we are booted from MacOS via BootX, we enter with the kernel * image loaded somewhere, and the following values in registers: * r3: 'BooX' (0x426f6f58) * r4: virtual address of boot_infos_t * r5: 0 * * PREP * This is jumped to on prep systems right after the kernel is relocated * to its proper place in memory by the boot loader. The expected layout * of the regs is: * r3: ptr to residual data * r4: initrd_start or if no initrd then 0 * r5: initrd_end - unused if r4 is 0 * r6: Start of command line string * r7: End of command line string * * This just gets a minimal mmu environment setup so we can call * start_here() to do the real work. * -- Cort */ .globl __start __start: /* * We have to do any OF calls before we map ourselves to KERNELBASE, * because OF may have I/O devices mapped into that area * (particularly on CHRP). */ cmpwi 0,r5,0 beq 1f #ifdef CONFIG_PPC_OF_BOOT_TRAMPOLINE /* find out where we are now */ bcl 20,31,$+4 0: mflr r8 /* r8 = runtime addr here */ addis r8,r8,(_stext - 0b)@ha addi r8,r8,(_stext - 0b)@l /* current runtime base addr */ bl prom_init #endif /* CONFIG_PPC_OF_BOOT_TRAMPOLINE */ /* We never return. We also hit that trap if trying to boot * from OF while CONFIG_PPC_OF_BOOT_TRAMPOLINE isn't selected */ trap /* * Check for BootX signature when supporting PowerMac and branch to * appropriate trampoline if it's present */ #ifdef CONFIG_PPC_PMAC 1: lis r31,0x426f ori r31,r31,0x6f58 cmpw 0,r3,r31 bne 1f bl bootx_init trap #endif /* CONFIG_PPC_PMAC */ 1: mr r31,r3 /* save device tree ptr */ li r24,0 /* cpu # */ /* * early_init() does the early machine identification and does * the necessary low-level setup and clears the BSS * -- Cort */ bl early_init /* Switch MMU off, clear BATs and flush TLB. At this point, r3 contains * the physical address we are running at, returned by early_init() */ bl mmu_off __after_mmu_off: bl clear_bats bl flush_tlbs bl initial_bats bl load_segment_registers bl reloc_offset bl early_hash_table #if defined(CONFIG_BOOTX_TEXT) bl setup_disp_bat #endif #ifdef CONFIG_PPC_EARLY_DEBUG_CPM bl setup_cpm_bat #endif #ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO bl setup_usbgecko_bat #endif /* * Call setup_cpu for CPU 0 and initialize 6xx Idle */ bl reloc_offset li r24,0 /* cpu# */ bl call_setup_cpu /* Call setup_cpu for this CPU */ bl reloc_offset bl init_idle_6xx /* * We need to run with _start at physical address 0. * On CHRP, we are loaded at 0x10000 since OF on CHRP uses * the exception vectors at 0 (and therefore this copy * overwrites OF's exception vectors with our own). * The MMU is off at this point. */ bl reloc_offset mr r26,r3 addis r4,r3,KERNELBASE@h /* current address of _start */ lis r5,PHYSICAL_START@h cmplw 0,r4,r5 /* already running at PHYSICAL_START? */ bne relocate_kernel /* * we now have the 1st 16M of ram mapped with the bats. * prep needs the mmu to be turned on here, but pmac already has it on. * this shouldn't bother the pmac since it just gets turned on again * as we jump to our code at KERNELBASE. -- Cort * Actually no, pmac doesn't have it on any more. BootX enters with MMU * off, and in other cases, we now turn it off before changing BATs above. */ turn_on_mmu: mfmsr r0 ori r0,r0,MSR_DR|MSR_IR|MSR_RI mtspr SPRN_SRR1,r0 lis r0,start_here@h ori r0,r0,start_here@l mtspr SPRN_SRR0,r0 rfi /* enables MMU */ /* * We need __secondary_hold as a place to hold the other cpus on * an SMP machine, even when we are running a UP kernel. */ . = 0xc0 /* for prep bootloader */ li r3,1 /* MTX only has 1 cpu */ .globl __secondary_hold __secondary_hold: /* tell the master we're here */ stw r3,__secondary_hold_acknowledge@l(0) #ifdef CONFIG_SMP 100: lwz r4,0(0) /* wait until we're told to start */ cmpw 0,r4,r3 bne 100b /* our cpu # was at addr 0 - go */ mr r24,r3 /* cpu # */ b __secondary_start #else b . #endif /* CONFIG_SMP */ .globl __secondary_hold_spinloop __secondary_hold_spinloop: .long 0 .globl __secondary_hold_acknowledge __secondary_hold_acknowledge: .long -1 /* System reset */ /* core99 pmac starts the seconary here by changing the vector, and putting it back to what it was (unknown_async_exception) when done. */ EXCEPTION(0x100, Reset, unknown_async_exception) /* Machine check */ /* * On CHRP, this is complicated by the fact that we could get a * machine check inside RTAS, and we have no guarantee that certain * critical registers will have the values we expect. The set of * registers that might have bad values includes all the GPRs * and all the BATs. We indicate that we are in RTAS by putting * a non-zero value, the address of the exception frame to use, * in thread.rtas_sp. The machine check handler checks thread.rtas_sp * and uses its value if it is non-zero. * (Other exception handlers assume that r1 is a valid kernel stack * pointer when we take an exception from supervisor mode.) * -- paulus. */ START_EXCEPTION(0x200, MachineCheck) EXCEPTION_PROLOG_0 #ifdef CONFIG_PPC_CHRP mtspr SPRN_SPRG_SCRATCH2,r1 mfspr r1, SPRN_SPRG_THREAD lwz r1, RTAS_SP(r1) cmpwi cr1, r1, 0 bne cr1, 7f mfspr r1, SPRN_SPRG_SCRATCH2 #endif /* CONFIG_PPC_CHRP */ EXCEPTION_PROLOG_1 7: EXCEPTION_PROLOG_2 0x200 MachineCheck #ifdef CONFIG_PPC_CHRP beq cr1, 1f twi 31, 0, 0 #endif 1: prepare_transfer_to_handler bl machine_check_exception b interrupt_return /* Data access exception. */ START_EXCEPTION(0x300, DataAccess) #ifdef CONFIG_PPC_BOOK3S_604 BEGIN_MMU_FTR_SECTION mtspr SPRN_SPRG_SCRATCH2,r10 mfspr r10, SPRN_SPRG_THREAD stw r11, THR11(r10) mfspr r10, SPRN_DSISR mfcr r11 andis. r10, r10, (DSISR_BAD_FAULT_32S | DSISR_DABRMATCH)@h mfspr r10, SPRN_SPRG_THREAD beq hash_page_dsi .Lhash_page_dsi_cont: mtcr r11 lwz r11, THR11(r10) mfspr r10, SPRN_SPRG_SCRATCH2 MMU_FTR_SECTION_ELSE b 1f ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_HPTE_TABLE) #endif 1: EXCEPTION_PROLOG_0 handle_dar_dsisr=1 EXCEPTION_PROLOG_1 EXCEPTION_PROLOG_2 0x300 DataAccess handle_dar_dsisr=1 prepare_transfer_to_handler lwz r5, _DSISR(r11) andis. r0, r5, DSISR_DABRMATCH@h bne- 1f bl do_page_fault b interrupt_return 1: bl do_break REST_NVGPRS(r1) b interrupt_return /* Instruction access exception. */ START_EXCEPTION(0x400, InstructionAccess) mtspr SPRN_SPRG_SCRATCH0,r10 mtspr SPRN_SPRG_SCRATCH1,r11 mfspr r10, SPRN_SPRG_THREAD mfspr r11, SPRN_SRR0 stw r11, SRR0(r10) mfspr r11, SPRN_SRR1 /* check whether user or kernel */ stw r11, SRR1(r10) mfcr r10 #ifdef CONFIG_PPC_BOOK3S_604 BEGIN_MMU_FTR_SECTION andis. r11, r11, SRR1_ISI_NOPT@h /* no pte found? */ bne hash_page_isi .Lhash_page_isi_cont: mfspr r11, SPRN_SRR1 /* check whether user or kernel */ END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE) #endif andi. r11, r11, MSR_PR EXCEPTION_PROLOG_1 EXCEPTION_PROLOG_2 0x400 InstructionAccess andis. r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */ stw r5, _DSISR(r11) stw r12, _DAR(r11) prepare_transfer_to_handler bl do_page_fault b interrupt_return /* External interrupt */ EXCEPTION(0x500, HardwareInterrupt, do_IRQ) /* Alignment exception */ START_EXCEPTION(0x600, Alignment) EXCEPTION_PROLOG 0x600 Alignment handle_dar_dsisr=1 prepare_transfer_to_handler bl alignment_exception REST_NVGPRS(r1) b interrupt_return /* Program check exception */ START_EXCEPTION(0x700, ProgramCheck) EXCEPTION_PROLOG 0x700 ProgramCheck prepare_transfer_to_handler bl program_check_exception REST_NVGPRS(r1) b interrupt_return /* Floating-point unavailable */ START_EXCEPTION(0x800, FPUnavailable) #ifdef CONFIG_PPC_FPU BEGIN_FTR_SECTION /* * Certain Freescale cores don't have a FPU and treat fp instructions * as a FP Unavailable exception. Redirect to illegal/emulation handling. */ b ProgramCheck END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE) EXCEPTION_PROLOG 0x800 FPUnavailable 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 #else b ProgramCheck #endif /* Decrementer */ EXCEPTION(0x900, Decrementer, timer_interrupt) EXCEPTION(0xa00, Trap_0a, unknown_exception) EXCEPTION(0xb00, Trap_0b, unknown_exception) /* System call */ START_EXCEPTION(0xc00, SystemCall) SYSCALL_ENTRY 0xc00 EXCEPTION(0xd00, SingleStep, single_step_exception) EXCEPTION(0xe00, Trap_0e, unknown_exception) /* * The Altivec unavailable trap is at 0x0f20. Foo. * We effectively remap it to 0x3000. * We include an altivec unavailable exception vector even if * not configured for Altivec, so that you can't panic a * non-altivec kernel running on a machine with altivec just * by executing an altivec instruction. */ START_EXCEPTION(0xf00, PerformanceMonitorTrap) b PerformanceMonitor START_EXCEPTION(0xf20, AltiVecUnavailableTrap) b AltiVecUnavailable __HEAD /* * Handle TLB miss for instruction on 603/603e. * Note: we get an alternate set of r0 - r3 to use automatically. */ . = 0x1000 InstructionTLBMiss: /* * r0: scratch * r1: linux style pte ( later becomes ppc hardware pte ) * r2: ptr to linux-style pte * r3: scratch */ /* Get PTE (linux-style) and check access */ mfspr r3,SPRN_IMISS #ifdef CONFIG_MODULES lis r1, TASK_SIZE@h /* check if kernel address */ cmplw 0,r1,r3 #endif mfspr r2, SPRN_SDR1 li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC | _PAGE_USER rlwinm r2, r2, 28, 0xfffff000 #ifdef CONFIG_MODULES bgt- 112f lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */ li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */ #endif 112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */ lwz r2,0(r2) /* get pmd entry */ rlwinm. r2,r2,0,0,19 /* extract address of pte page */ beq- InstructionAddressInvalid /* return if no mapping */ rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */ lwz r0,0(r2) /* get linux-style pte */ andc. r1,r1,r0 /* check access & ~permission */ bne- InstructionAddressInvalid /* return if access not permitted */ /* Convert linux-style PTE to low word of PPC-style PTE */ rlwimi r0,r0,32-2,31,31 /* _PAGE_USER -> PP lsb */ ori r1, r1, 0xe06 /* clear out reserved bits */ andc r1, r0, r1 /* PP = user? 1 : 0 */ BEGIN_FTR_SECTION rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT) mtspr SPRN_RPA,r1 tlbli r3 mfspr r3,SPRN_SRR1 /* Need to restore CR0 */ mtcrf 0x80,r3 rfi InstructionAddressInvalid: mfspr r3,SPRN_SRR1 rlwinm r1,r3,9,6,6 /* Get load/store bit */ addis r1,r1,0x2000 mtspr SPRN_DSISR,r1 /* (shouldn't be needed) */ andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */ or r2,r2,r1 mtspr SPRN_SRR1,r2 mfspr r1,SPRN_IMISS /* Get failing address */ rlwinm. r2,r2,0,31,31 /* Check for little endian access */ rlwimi r2,r2,1,30,30 /* change 1 -> 3 */ xor r1,r1,r2 mtspr SPRN_DAR,r1 /* Set fault address */ mfmsr r0 /* Restore "normal" registers */ xoris r0,r0,MSR_TGPR>>16 mtcrf 0x80,r3 /* Restore CR0 */ mtmsr r0 b InstructionAccess /* * Handle TLB miss for DATA Load operation on 603/603e */ . = 0x1100 DataLoadTLBMiss: /* * r0: scratch * r1: linux style pte ( later becomes ppc hardware pte ) * r2: ptr to linux-style pte * r3: scratch */ /* Get PTE (linux-style) and check access */ mfspr r3,SPRN_DMISS lis r1, TASK_SIZE@h /* check if kernel address */ cmplw 0,r1,r3 mfspr r2, SPRN_SDR1 li r1, _PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_USER rlwinm r2, r2, 28, 0xfffff000 bgt- 112f lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */ li r1, _PAGE_PRESENT | _PAGE_ACCESSED addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */ 112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */ lwz r2,0(r2) /* get pmd entry */ rlwinm. r2,r2,0,0,19 /* extract address of pte page */ beq- DataAddressInvalid /* return if no mapping */ rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */ lwz r0,0(r2) /* get linux-style pte */ andc. r1,r1,r0 /* check access & ~permission */ bne- DataAddressInvalid /* return if access not permitted */ /* * NOTE! We are assuming this is not an SMP system, otherwise * we would need to update the pte atomically with lwarx/stwcx. */ /* Convert linux-style PTE to low word of PPC-style PTE */ rlwinm r1,r0,32-9,30,30 /* _PAGE_RW -> PP msb */ rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */ rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */ ori r1,r1,0xe04 /* clear out reserved bits */ andc r1,r0,r1 /* PP = user? rw? 1: 3: 0 */ BEGIN_FTR_SECTION rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT) mtspr SPRN_RPA,r1 mfspr r2,SPRN_SRR1 /* Need to restore CR0 */ mtcrf 0x80,r2 BEGIN_MMU_FTR_SECTION li r0,1 mfspr r1,SPRN_SPRG_603_LRU rlwinm r2,r3,20,27,31 /* Get Address bits 15:19 */ slw r0,r0,r2 xor r1,r0,r1 srw r0,r1,r2 mtspr SPRN_SPRG_603_LRU,r1 mfspr r2,SPRN_SRR1 rlwimi r2,r0,31-14,14,14 mtspr SPRN_SRR1,r2 END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU) tlbld r3 rfi DataAddressInvalid: mfspr r3,SPRN_SRR1 rlwinm r1,r3,9,6,6 /* Get load/store bit */ addis r1,r1,0x2000 mtspr SPRN_DSISR,r1 andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */ mtspr SPRN_SRR1,r2 mfspr r1,SPRN_DMISS /* Get failing address */ rlwinm. r2,r2,0,31,31 /* Check for little endian access */ beq 20f /* Jump if big endian */ xori r1,r1,3 20: mtspr SPRN_DAR,r1 /* Set fault address */ mfmsr r0 /* Restore "normal" registers */ xoris r0,r0,MSR_TGPR>>16 mtcrf 0x80,r3 /* Restore CR0 */ mtmsr r0 b DataAccess /* * Handle TLB miss for DATA Store on 603/603e */ . = 0x1200 DataStoreTLBMiss: /* * r0: scratch * r1: linux style pte ( later becomes ppc hardware pte ) * r2: ptr to linux-style pte * r3: scratch */ /* Get PTE (linux-style) and check access */ mfspr r3,SPRN_DMISS lis r1, TASK_SIZE@h /* check if kernel address */ cmplw 0,r1,r3 mfspr r2, SPRN_SDR1 li r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_USER rlwinm r2, r2, 28, 0xfffff000 bgt- 112f lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */ li r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT | _PAGE_ACCESSED addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */ 112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */ lwz r2,0(r2) /* get pmd entry */ rlwinm. r2,r2,0,0,19 /* extract address of pte page */ beq- DataAddressInvalid /* return if no mapping */ rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */ lwz r0,0(r2) /* get linux-style pte */ andc. r1,r1,r0 /* check access & ~permission */ bne- DataAddressInvalid /* return if access not permitted */ /* * NOTE! We are assuming this is not an SMP system, otherwise * we would need to update the pte atomically with lwarx/stwcx. */ /* Convert linux-style PTE to low word of PPC-style PTE */ rlwimi r0,r0,32-2,31,31 /* _PAGE_USER -> PP lsb */ li r1,0xe06 /* clear out reserved bits & PP msb */ andc r1,r0,r1 /* PP = user? 1: 0 */ BEGIN_FTR_SECTION rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT) mtspr SPRN_RPA,r1 mfspr r2,SPRN_SRR1 /* Need to restore CR0 */ mtcrf 0x80,r2 BEGIN_MMU_FTR_SECTION li r0,1 mfspr r1,SPRN_SPRG_603_LRU rlwinm r2,r3,20,27,31 /* Get Address bits 15:19 */ slw r0,r0,r2 xor r1,r0,r1 srw r0,r1,r2 mtspr SPRN_SPRG_603_LRU,r1 mfspr r2,SPRN_SRR1 rlwimi r2,r0,31-14,14,14 mtspr SPRN_SRR1,r2 END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU) tlbld r3 rfi #ifndef CONFIG_ALTIVEC #define altivec_assist_exception unknown_exception #endif #ifndef CONFIG_TAU_INT #define TAUException unknown_async_exception #endif EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception) EXCEPTION(0x1400, SMI, SMIException) EXCEPTION(0x1500, Trap_15, unknown_exception) EXCEPTION(0x1600, Trap_16, altivec_assist_exception) EXCEPTION(0x1700, Trap_17, TAUException) EXCEPTION(0x1800, Trap_18, unknown_exception) EXCEPTION(0x1900, Trap_19, unknown_exception) EXCEPTION(0x1a00, Trap_1a, unknown_exception) EXCEPTION(0x1b00, Trap_1b, unknown_exception) EXCEPTION(0x1c00, Trap_1c, unknown_exception) EXCEPTION(0x1d00, Trap_1d, unknown_exception) EXCEPTION(0x1e00, Trap_1e, unknown_exception) EXCEPTION(0x1f00, Trap_1f, unknown_exception) EXCEPTION(0x2000, RunMode, RunModeException) EXCEPTION(0x2100, Trap_21, unknown_exception) EXCEPTION(0x2200, Trap_22, unknown_exception) EXCEPTION(0x2300, Trap_23, unknown_exception) EXCEPTION(0x2400, Trap_24, unknown_exception) EXCEPTION(0x2500, Trap_25, unknown_exception) EXCEPTION(0x2600, Trap_26, unknown_exception) EXCEPTION(0x2700, Trap_27, unknown_exception) EXCEPTION(0x2800, Trap_28, unknown_exception) EXCEPTION(0x2900, Trap_29, unknown_exception) EXCEPTION(0x2a00, Trap_2a, unknown_exception) EXCEPTION(0x2b00, Trap_2b, unknown_exception) EXCEPTION(0x2c00, Trap_2c, unknown_exception) EXCEPTION(0x2d00, Trap_2d, unknown_exception) EXCEPTION(0x2e00, Trap_2e, unknown_exception) EXCEPTION(0x2f00, Trap_2f, unknown_exception) __HEAD . = 0x3000 #ifdef CONFIG_PPC_BOOK3S_604 .macro save_regs_thread thread stw r0, THR0(\thread) stw r3, THR3(\thread) stw r4, THR4(\thread) stw r5, THR5(\thread) stw r6, THR6(\thread) stw r8, THR8(\thread) stw r9, THR9(\thread) mflr r0 stw r0, THLR(\thread) mfctr r0 stw r0, THCTR(\thread) .endm .macro restore_regs_thread thread lwz r0, THLR(\thread) mtlr r0 lwz r0, THCTR(\thread) mtctr r0 lwz r0, THR0(\thread) lwz r3, THR3(\thread) lwz r4, THR4(\thread) lwz r5, THR5(\thread) lwz r6, THR6(\thread) lwz r8, THR8(\thread) lwz r9, THR9(\thread) .endm hash_page_dsi: save_regs_thread r10 mfdsisr r3 mfdar r4 mfsrr0 r5 mfsrr1 r9 rlwinm r3, r3, 32 - 15, _PAGE_RW /* DSISR_STORE -> _PAGE_RW */ bl hash_page mfspr r10, SPRN_SPRG_THREAD restore_regs_thread r10 b .Lhash_page_dsi_cont hash_page_isi: mr r11, r10 mfspr r10, SPRN_SPRG_THREAD save_regs_thread r10 li r3, 0 lwz r4, SRR0(r10) lwz r9, SRR1(r10) bl hash_page mfspr r10, SPRN_SPRG_THREAD restore_regs_thread r10 mr r10, r11 b .Lhash_page_isi_cont .globl fast_hash_page_return fast_hash_page_return: andis. r10, r9, SRR1_ISI_NOPT@h /* Set on ISI, cleared on DSI */ mfspr r10, SPRN_SPRG_THREAD restore_regs_thread r10 bne 1f /* DSI */ mtcr r11 lwz r11, THR11(r10) mfspr r10, SPRN_SPRG_SCRATCH2 rfi 1: /* ISI */ mtcr r11 mfspr r11, SPRN_SPRG_SCRATCH1 mfspr r10, SPRN_SPRG_SCRATCH0 rfi #endif /* CONFIG_PPC_BOOK3S_604 */ #ifdef CONFIG_VMAP_STACK vmap_stack_overflow_exception #endif __HEAD AltiVecUnavailable: EXCEPTION_PROLOG 0xf20 AltiVecUnavailable #ifdef CONFIG_ALTIVEC beq 1f bl load_up_altivec /* if from user, just load it up */ b fast_exception_return #endif /* CONFIG_ALTIVEC */ 1: prepare_transfer_to_handler bl altivec_unavailable_exception b interrupt_return __HEAD PerformanceMonitor: EXCEPTION_PROLOG 0xf00 PerformanceMonitor prepare_transfer_to_handler bl performance_monitor_exception b interrupt_return __HEAD /* * This code is jumped to from the startup code to copy * the kernel image to physical address PHYSICAL_START. */ relocate_kernel: addis r9,r26,klimit@ha /* fetch klimit */ lwz r25,klimit@l(r9) addis r25,r25,-KERNELBASE@h lis r3,PHYSICAL_START@h /* Destination base address */ li r6,0 /* Destination offset */ li r5,0x4000 /* # bytes of memory to copy */ bl copy_and_flush /* copy the first 0x4000 bytes */ addi r0,r3,4f@l /* jump to the address of 4f */ mtctr r0 /* in copy and do the rest. */ bctr /* jump to the copy */ 4: mr r5,r25 bl copy_and_flush /* copy the rest */ b turn_on_mmu /* * Copy routine used to copy the kernel to start at physical address 0 * and flush and invalidate the caches as needed. * r3 = dest addr, r4 = source addr, r5 = copy limit, r6 = start offset * on exit, r3, r4, r5 are unchanged, r6 is updated to be >= r5. */ _ENTRY(copy_and_flush) addi r5,r5,-4 addi r6,r6,-4 4: li r0,L1_CACHE_BYTES/4 mtctr r0 3: addi r6,r6,4 /* copy a cache line */ lwzx r0,r6,r4 stwx r0,r6,r3 bdnz 3b dcbst r6,r3 /* write it to memory */ sync icbi r6,r3 /* flush the icache line */ cmplw 0,r6,r5 blt 4b sync /* additional sync needed on g4 */ isync addi r5,r5,4 addi r6,r6,4 blr #ifdef CONFIG_SMP .globl __secondary_start_mpc86xx __secondary_start_mpc86xx: mfspr r3, SPRN_PIR stw r3, __secondary_hold_acknowledge@l(0) mr r24, r3 /* cpu # */ b __secondary_start .globl __secondary_start_pmac_0 __secondary_start_pmac_0: /* NB the entries for cpus 0, 1, 2 must each occupy 8 bytes. */ li r24,0 b 1f li r24,1 b 1f li r24,2 b 1f li r24,3 1: /* on powersurge, we come in here with IR=0 and DR=1, and DBAT 0 set to map the 0xf0000000 - 0xffffffff region */ mfmsr r0 rlwinm r0,r0,0,28,26 /* clear DR (0x10) */ mtmsr r0 isync .globl __secondary_start __secondary_start: /* Copy some CPU settings from CPU 0 */ bl __restore_cpu_setup lis r3,-KERNELBASE@h mr r4,r24 bl call_setup_cpu /* Call setup_cpu for this CPU */ lis r3,-KERNELBASE@h bl init_idle_6xx /* get current's stack and current */ lis r2,secondary_current@ha tophys(r2,r2) lwz r2,secondary_current@l(r2) tophys(r1,r2) lwz r1,TASK_STACK(r1) /* stack */ addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD li r0,0 tophys(r3,r1) stw r0,0(r3) /* load up the MMU */ bl load_segment_registers bl load_up_mmu /* ptr to phys current thread */ tophys(r4,r2) addi r4,r4,THREAD /* phys address of our thread_struct */ mtspr SPRN_SPRG_THREAD,r4 BEGIN_MMU_FTR_SECTION lis r4, (swapper_pg_dir - PAGE_OFFSET)@h ori r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l rlwinm r4, r4, 4, 0xffff01ff mtspr SPRN_SDR1, r4 END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE) /* enable MMU and jump to start_secondary */ li r4,MSR_KERNEL lis r3,start_secondary@h ori r3,r3,start_secondary@l mtspr SPRN_SRR0,r3 mtspr SPRN_SRR1,r4 rfi #endif /* CONFIG_SMP */ #ifdef CONFIG_KVM_BOOK3S_HANDLER #include "../kvm/book3s_rmhandlers.S" #endif /* * Load stuff into the MMU. Intended to be called with * IR=0 and DR=0. */ early_hash_table: sync /* Force all PTE updates to finish */ isync tlbia /* Clear all TLB entries */ sync /* wait for tlbia/tlbie to finish */ TLBSYNC /* ... on all CPUs */ /* Load the SDR1 register (hash table base & size) */ lis r6, early_hash - PAGE_OFFSET@h ori r6, r6, 3 /* 256kB table */ mtspr SPRN_SDR1, r6 blr load_up_mmu: sync /* Force all PTE updates to finish */ isync tlbia /* Clear all TLB entries */ sync /* wait for tlbia/tlbie to finish */ TLBSYNC /* ... on all CPUs */ BEGIN_MMU_FTR_SECTION /* Load the SDR1 register (hash table base & size) */ lis r6,_SDR1@ha tophys(r6,r6) lwz r6,_SDR1@l(r6) mtspr SPRN_SDR1,r6 END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE) /* Load the BAT registers with the values set up by MMU_init. */ lis r3,BATS@ha addi r3,r3,BATS@l tophys(r3,r3) LOAD_BAT(0,r3,r4,r5) LOAD_BAT(1,r3,r4,r5) LOAD_BAT(2,r3,r4,r5) LOAD_BAT(3,r3,r4,r5) BEGIN_MMU_FTR_SECTION LOAD_BAT(4,r3,r4,r5) LOAD_BAT(5,r3,r4,r5) LOAD_BAT(6,r3,r4,r5) LOAD_BAT(7,r3,r4,r5) END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS) blr _GLOBAL(load_segment_registers) li r0, NUM_USER_SEGMENTS /* load up user segment register values */ mtctr r0 /* for context 0 */ li r3, 0 /* Kp = 0, Ks = 0, VSID = 0 */ #ifdef CONFIG_PPC_KUEP oris r3, r3, SR_NX@h /* Set Nx */ #endif #ifdef CONFIG_PPC_KUAP oris r3, r3, SR_KS@h /* Set Ks */ #endif li r4, 0 3: mtsrin r3, r4 addi r3, r3, 0x111 /* increment VSID */ addis r4, r4, 0x1000 /* address of next segment */ bdnz 3b li r0, 16 - NUM_USER_SEGMENTS /* load up kernel segment registers */ mtctr r0 /* for context 0 */ rlwinm r3, r3, 0, ~SR_NX /* Nx = 0 */ rlwinm r3, r3, 0, ~SR_KS /* Ks = 0 */ oris r3, r3, SR_KP@h /* Kp = 1 */ 3: mtsrin r3, r4 addi r3, r3, 0x111 /* increment VSID */ addis r4, r4, 0x1000 /* address of next segment */ bdnz 3b blr /* * This is where the main kernel code starts. */ start_here: /* ptr to current */ lis r2,init_task@h ori r2,r2,init_task@l /* Set up for using our exception vectors */ /* ptr to phys current thread */ tophys(r4,r2) addi r4,r4,THREAD /* init task's THREAD */ mtspr SPRN_SPRG_THREAD,r4 BEGIN_MMU_FTR_SECTION lis r4, (swapper_pg_dir - PAGE_OFFSET)@h ori r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l rlwinm r4, r4, 4, 0xffff01ff mtspr SPRN_SDR1, r4 END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE) /* stack */ lis r1,init_thread_union@ha addi r1,r1,init_thread_union@l li r0,0 stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1) /* * Do early platform-specific initialization, * and set up the MMU. */ #ifdef CONFIG_KASAN bl kasan_early_init #endif li r3,0 mr r4,r31 bl machine_init bl __save_cpu_setup bl MMU_init bl MMU_init_hw_patch /* * Go back to running unmapped so we can load up new values * for SDR1 (hash table pointer) and the segment registers * and change to using our exception vectors. */ lis r4,2f@h ori r4,r4,2f@l tophys(r4,r4) li r3,MSR_KERNEL & ~(MSR_IR|MSR_DR) .align 4 mtspr SPRN_SRR0,r4 mtspr SPRN_SRR1,r3 rfi /* Load up the kernel context */ 2: bl load_up_mmu #ifdef CONFIG_BDI_SWITCH /* Add helper information for the Abatron bdiGDB debugger. * We do this here because we know the mmu is disabled, and * will be enabled for real in just a few instructions. */ lis r5, abatron_pteptrs@h ori r5, r5, abatron_pteptrs@l stw r5, 0xf0(0) /* This much match your Abatron config */ lis r6, swapper_pg_dir@h ori r6, r6, swapper_pg_dir@l tophys(r5, r5) stw r6, 0(r5) #endif /* CONFIG_BDI_SWITCH */ /* Now turn on the MMU for real! */ li r4,MSR_KERNEL lis r3,start_kernel@h ori r3,r3,start_kernel@l mtspr SPRN_SRR0,r3 mtspr SPRN_SRR1,r4 rfi /* * void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next); * * Set up the segment registers for a new context. */ _ENTRY(switch_mmu_context) lwz r3,MMCONTEXTID(r4) cmpwi cr0,r3,0 blt- 4f mulli r3,r3,897 /* multiply context by skew factor */ rlwinm r3,r3,4,8,27 /* VSID = (context & 0xfffff) << 4 */ #ifdef CONFIG_PPC_KUEP oris r3, r3, SR_NX@h /* Set Nx */ #endif #ifdef CONFIG_PPC_KUAP oris r3, r3, SR_KS@h /* Set Ks */ #endif li r0,NUM_USER_SEGMENTS mtctr r0 #ifdef CONFIG_BDI_SWITCH /* Context switch the PTE pointer for the Abatron BDI2000. * The PGDIR is passed as second argument. */ lwz r4, MM_PGD(r4) lis r5, abatron_pteptrs@ha stw r4, abatron_pteptrs@l + 0x4(r5) #endif BEGIN_MMU_FTR_SECTION #ifndef CONFIG_BDI_SWITCH lwz r4, MM_PGD(r4) #endif tophys(r4, r4) rlwinm r4, r4, 4, 0xffff01ff mtspr SPRN_SDR1, r4 END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE) li r4,0 isync 3: mtsrin r3,r4 addi r3,r3,0x111 /* next VSID */ rlwinm r3,r3,0,8,3 /* clear out any overflow from VSID field */ addis r4,r4,0x1000 /* address of next segment */ bdnz 3b sync isync blr 4: trap EMIT_BUG_ENTRY 4b,__FILE__,__LINE__,0 blr EXPORT_SYMBOL(switch_mmu_context) /* * An undocumented "feature" of 604e requires that the v bit * be cleared before changing BAT values. * * Also, newer IBM firmware does not clear bat3 and 4 so * this makes sure it's done. * -- Cort */ clear_bats: li r10,0 mtspr SPRN_DBAT0U,r10 mtspr SPRN_DBAT0L,r10 mtspr SPRN_DBAT1U,r10 mtspr SPRN_DBAT1L,r10 mtspr SPRN_DBAT2U,r10 mtspr SPRN_DBAT2L,r10 mtspr SPRN_DBAT3U,r10 mtspr SPRN_DBAT3L,r10 mtspr SPRN_IBAT0U,r10 mtspr SPRN_IBAT0L,r10 mtspr SPRN_IBAT1U,r10 mtspr SPRN_IBAT1L,r10 mtspr SPRN_IBAT2U,r10 mtspr SPRN_IBAT2L,r10 mtspr SPRN_IBAT3U,r10 mtspr SPRN_IBAT3L,r10 BEGIN_MMU_FTR_SECTION /* Here's a tweak: at this point, CPU setup have * not been called yet, so HIGH_BAT_EN may not be * set in HID0 for the 745x processors. However, it * seems that doesn't affect our ability to actually * write to these SPRs. */ mtspr SPRN_DBAT4U,r10 mtspr SPRN_DBAT4L,r10 mtspr SPRN_DBAT5U,r10 mtspr SPRN_DBAT5L,r10 mtspr SPRN_DBAT6U,r10 mtspr SPRN_DBAT6L,r10 mtspr SPRN_DBAT7U,r10 mtspr SPRN_DBAT7L,r10 mtspr SPRN_IBAT4U,r10 mtspr SPRN_IBAT4L,r10 mtspr SPRN_IBAT5U,r10 mtspr SPRN_IBAT5L,r10 mtspr SPRN_IBAT6U,r10 mtspr SPRN_IBAT6L,r10 mtspr SPRN_IBAT7U,r10 mtspr SPRN_IBAT7L,r10 END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS) blr _ENTRY(update_bats) lis r4, 1f@h ori r4, r4, 1f@l tophys(r4, r4) mfmsr r6 mflr r7 li r3, MSR_KERNEL & ~(MSR_IR | MSR_DR) rlwinm r0, r6, 0, ~MSR_RI rlwinm r0, r0, 0, ~MSR_EE mtmsr r0 .align 4 mtspr SPRN_SRR0, r4 mtspr SPRN_SRR1, r3 rfi 1: bl clear_bats lis r3, BATS@ha addi r3, r3, BATS@l tophys(r3, r3) LOAD_BAT(0, r3, r4, r5) LOAD_BAT(1, r3, r4, r5) LOAD_BAT(2, r3, r4, r5) LOAD_BAT(3, r3, r4, r5) BEGIN_MMU_FTR_SECTION LOAD_BAT(4, r3, r4, r5) LOAD_BAT(5, r3, r4, r5) LOAD_BAT(6, r3, r4, r5) LOAD_BAT(7, r3, r4, r5) END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS) li r3, MSR_KERNEL & ~(MSR_IR | MSR_DR | MSR_RI) mtmsr r3 mtspr SPRN_SRR0, r7 mtspr SPRN_SRR1, r6 rfi flush_tlbs: lis r10, 0x40 1: addic. r10, r10, -0x1000 tlbie r10 bgt 1b sync blr mmu_off: addi r4, r3, __after_mmu_off - _start mfmsr r3 andi. r0,r3,MSR_DR|MSR_IR /* MMU enabled? */ beqlr andc r3,r3,r0 .align 4 mtspr SPRN_SRR0,r4 mtspr SPRN_SRR1,r3 sync rfi /* We use one BAT to map up to 256M of RAM at _PAGE_OFFSET */ initial_bats: lis r11,PAGE_OFFSET@h tophys(r8,r11) #ifdef CONFIG_SMP ori r8,r8,0x12 /* R/W access, M=1 */ #else ori r8,r8,2 /* R/W access */ #endif /* CONFIG_SMP */ ori r11,r11,BL_256M<<2|0x2 /* set up BAT registers for 604 */ mtspr SPRN_DBAT0L,r8 /* N.B. 6xx have valid */ mtspr SPRN_DBAT0U,r11 /* bit in upper BAT register */ mtspr SPRN_IBAT0L,r8 mtspr SPRN_IBAT0U,r11 isync blr #ifdef CONFIG_BOOTX_TEXT setup_disp_bat: /* * setup the display bat prepared for us in prom.c */ mflr r8 bl reloc_offset mtlr r8 addis r8,r3,disp_BAT@ha addi r8,r8,disp_BAT@l cmpwi cr0,r8,0 beqlr lwz r11,0(r8) lwz r8,4(r8) mtspr SPRN_DBAT3L,r8 mtspr SPRN_DBAT3U,r11 blr #endif /* CONFIG_BOOTX_TEXT */ #ifdef CONFIG_PPC_EARLY_DEBUG_CPM setup_cpm_bat: lis r8, 0xf000 ori r8, r8, 0x002a mtspr SPRN_DBAT1L, r8 lis r11, 0xf000 ori r11, r11, (BL_1M << 2) | 2 mtspr SPRN_DBAT1U, r11 blr #endif #ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO setup_usbgecko_bat: /* prepare a BAT for early io */ #if defined(CONFIG_GAMECUBE) lis r8, 0x0c00 #elif defined(CONFIG_WII) lis r8, 0x0d00 #else #error Invalid platform for USB Gecko based early debugging. #endif /* * The virtual address used must match the virtual address * associated to the fixmap entry FIX_EARLY_DEBUG_BASE. */ lis r11, 0xfffe /* top 128K */ ori r8, r8, 0x002a /* uncached, guarded ,rw */ ori r11, r11, 0x2 /* 128K, Vs=1, Vp=0 */ mtspr SPRN_DBAT1L, r8 mtspr SPRN_DBAT1U, r11 blr #endif #ifdef CONFIG_8260 /* Jump into the system reset for the rom. * We first disable the MMU, and then jump to the ROM reset address. * * r3 is the board info structure, r4 is the location for starting. * I use this for building a small kernel that can load other kernels, * rather than trying to write or rely on a rom monitor that can tftp load. */ .globl m8260_gorom m8260_gorom: mfmsr r0 rlwinm r0,r0,0,17,15 /* clear MSR_EE in r0 */ sync mtmsr r0 sync mfspr r11, SPRN_HID0 lis r10, 0 ori r10,r10,HID0_ICE|HID0_DCE andc r11, r11, r10 mtspr SPRN_HID0, r11 isync li r5, MSR_ME|MSR_RI lis r6,2f@h addis r6,r6,-KERNELBASE@h ori r6,r6,2f@l mtspr SPRN_SRR0,r6 mtspr SPRN_SRR1,r5 isync sync rfi 2: mtlr r4 blr #endif /* * We put a few things here that have to be page-aligned. * This stuff goes at the beginning of the data segment, * which is page-aligned. */ .data .globl sdata sdata: .globl empty_zero_page empty_zero_page: .space 4096 EXPORT_SYMBOL(empty_zero_page) .globl swapper_pg_dir swapper_pg_dir: .space PGD_TABLE_SIZE /* Room for two PTE pointers, usually the kernel and current user pointers * to their respective root page table. */ abatron_pteptrs: .space 8