| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * Low level TLB miss handlers for Book3E |
| * |
| * Copyright (C) 2008-2009 |
| * Ben. Herrenschmidt (benh@kernel.crashing.org), IBM Corp. |
| */ |
| |
| #include <linux/pgtable.h> |
| #include <asm/processor.h> |
| #include <asm/reg.h> |
| #include <asm/page.h> |
| #include <asm/mmu.h> |
| #include <asm/ppc_asm.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/cputable.h> |
| #include <asm/exception-64e.h> |
| #include <asm/ppc-opcode.h> |
| #include <asm/kvm_asm.h> |
| #include <asm/kvm_booke_hv_asm.h> |
| #include <asm/feature-fixups.h> |
| |
| #define VPTE_PMD_SHIFT (PTE_INDEX_SIZE) |
| #define VPTE_PUD_SHIFT (VPTE_PMD_SHIFT + PMD_INDEX_SIZE) |
| #define VPTE_PGD_SHIFT (VPTE_PUD_SHIFT + PUD_INDEX_SIZE) |
| #define VPTE_INDEX_SIZE (VPTE_PGD_SHIFT + PGD_INDEX_SIZE) |
| |
| /********************************************************************** |
| * * |
| * TLB miss handling for Book3E with a bolted linear mapping * |
| * No virtual page table, no nested TLB misses * |
| * * |
| **********************************************************************/ |
| |
| /* |
| * Note that, unlike non-bolted handlers, TLB_EXFRAME is not |
| * modified by the TLB miss handlers themselves, since the TLB miss |
| * handler code will not itself cause a recursive TLB miss. |
| * |
| * TLB_EXFRAME will be modified when crit/mc/debug exceptions are |
| * entered/exited. |
| */ |
| .macro tlb_prolog_bolted intnum addr |
| mtspr SPRN_SPRG_GEN_SCRATCH,r12 |
| mfspr r12,SPRN_SPRG_TLB_EXFRAME |
| std r13,EX_TLB_R13(r12) |
| std r10,EX_TLB_R10(r12) |
| mfspr r13,SPRN_SPRG_PACA |
| |
| mfcr r10 |
| std r11,EX_TLB_R11(r12) |
| #ifdef CONFIG_KVM_BOOKE_HV |
| BEGIN_FTR_SECTION |
| mfspr r11, SPRN_SRR1 |
| END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV) |
| #endif |
| DO_KVM \intnum, SPRN_SRR1 |
| std r16,EX_TLB_R16(r12) |
| mfspr r16,\addr /* get faulting address */ |
| std r14,EX_TLB_R14(r12) |
| ld r14,PACAPGD(r13) |
| std r15,EX_TLB_R15(r12) |
| std r10,EX_TLB_CR(r12) |
| START_BTB_FLUSH_SECTION |
| mfspr r11, SPRN_SRR1 |
| andi. r10,r11,MSR_PR |
| beq 1f |
| BTB_FLUSH(r10) |
| 1: |
| END_BTB_FLUSH_SECTION |
| std r7,EX_TLB_R7(r12) |
| .endm |
| |
| .macro tlb_epilog_bolted |
| ld r14,EX_TLB_CR(r12) |
| ld r7,EX_TLB_R7(r12) |
| ld r10,EX_TLB_R10(r12) |
| ld r11,EX_TLB_R11(r12) |
| ld r13,EX_TLB_R13(r12) |
| mtcr r14 |
| ld r14,EX_TLB_R14(r12) |
| ld r15,EX_TLB_R15(r12) |
| ld r16,EX_TLB_R16(r12) |
| mfspr r12,SPRN_SPRG_GEN_SCRATCH |
| .endm |
| |
| /* Data TLB miss */ |
| START_EXCEPTION(data_tlb_miss_bolted) |
| tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR |
| |
| /* We need _PAGE_PRESENT and _PAGE_ACCESSED set */ |
| |
| /* We do the user/kernel test for the PID here along with the RW test |
| */ |
| /* We pre-test some combination of permissions to avoid double |
| * faults: |
| * |
| * We move the ESR:ST bit into the position of _PAGE_BAP_SW in the PTE |
| * ESR_ST is 0x00800000 |
| * _PAGE_BAP_SW is 0x00000010 |
| * So the shift is >> 19. This tests for supervisor writeability. |
| * If the page happens to be supervisor writeable and not user |
| * writeable, we will take a new fault later, but that should be |
| * a rare enough case. |
| * |
| * We also move ESR_ST in _PAGE_DIRTY position |
| * _PAGE_DIRTY is 0x00001000 so the shift is >> 11 |
| * |
| * MAS1 is preset for all we need except for TID that needs to |
| * be cleared for kernel translations |
| */ |
| |
| mfspr r11,SPRN_ESR |
| |
| srdi r15,r16,60 /* get region */ |
| rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 |
| bne- dtlb_miss_fault_bolted /* Bail if fault addr is invalid */ |
| |
| rlwinm r10,r11,32-19,27,27 |
| rlwimi r10,r11,32-16,19,19 |
| cmpwi r15,0 /* user vs kernel check */ |
| ori r10,r10,_PAGE_PRESENT |
| oris r11,r10,_PAGE_ACCESSED@h |
| |
| bne tlb_miss_kernel_bolted |
| |
| tlb_miss_user_bolted: |
| #ifdef CONFIG_PPC_KUAP |
| mfspr r10,SPRN_MAS1 |
| rlwinm. r10,r10,0,0x3fff0000 |
| beq- tlb_miss_fault_bolted /* KUAP fault */ |
| #endif |
| |
| tlb_miss_common_bolted: |
| /* |
| * This is the guts of the TLB miss handler for bolted-linear. |
| * We are entered with: |
| * |
| * r16 = faulting address |
| * r15 = crap (free to use) |
| * r14 = page table base |
| * r13 = PACA |
| * r11 = PTE permission mask |
| * r10 = crap (free to use) |
| */ |
| rldicl r15,r16,64-PGDIR_SHIFT+3,64-PGD_INDEX_SIZE-3 |
| cmpldi cr0,r14,0 |
| clrrdi r15,r15,3 |
| beq tlb_miss_fault_bolted /* No PGDIR, bail */ |
| |
| ldx r14,r14,r15 /* grab pgd entry */ |
| |
| rldicl r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3 |
| clrrdi r15,r15,3 |
| cmpdi cr0,r14,0 |
| bge tlb_miss_fault_bolted /* Bad pgd entry or hugepage; bail */ |
| ldx r14,r14,r15 /* grab pud entry */ |
| |
| rldicl r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3 |
| clrrdi r15,r15,3 |
| cmpdi cr0,r14,0 |
| bge tlb_miss_fault_bolted |
| ldx r14,r14,r15 /* Grab pmd entry */ |
| |
| rldicl r15,r16,64-PAGE_SHIFT+3,64-PTE_INDEX_SIZE-3 |
| clrrdi r15,r15,3 |
| cmpdi cr0,r14,0 |
| bge tlb_miss_fault_bolted |
| ldx r14,r14,r15 /* Grab PTE, normal (!huge) page */ |
| |
| /* Check if required permissions are met */ |
| andc. r15,r11,r14 |
| rldicr r15,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT |
| bne- tlb_miss_fault_bolted |
| |
| /* Now we build the MAS: |
| * |
| * MAS 0 : Fully setup with defaults in MAS4 and TLBnCFG |
| * MAS 1 : Almost fully setup |
| * - PID already updated by caller if necessary |
| * - TSIZE need change if !base page size, not |
| * yet implemented for now |
| * MAS 2 : Defaults not useful, need to be redone |
| * MAS 3+7 : Needs to be done |
| */ |
| clrrdi r11,r16,12 /* Clear low crap in EA */ |
| clrldi r15,r15,12 /* Clear crap at the top */ |
| rlwimi r11,r14,32-19,27,31 /* Insert WIMGE */ |
| rlwimi r15,r14,32-8,22,25 /* Move in U bits */ |
| mtspr SPRN_MAS2,r11 |
| andi. r11,r14,_PAGE_DIRTY |
| rlwimi r15,r14,32-2,26,31 /* Move in BAP bits */ |
| |
| /* Mask out SW and UW if !DIRTY (XXX optimize this !) */ |
| bne 1f |
| li r11,MAS3_SW|MAS3_UW |
| andc r15,r15,r11 |
| 1: |
| mtspr SPRN_MAS7_MAS3,r15 |
| tlbwe |
| |
| tlb_miss_done_bolted: |
| tlb_epilog_bolted |
| rfi |
| |
| itlb_miss_kernel_bolted: |
| li r11,_PAGE_PRESENT|_PAGE_BAP_SX /* Base perm */ |
| oris r11,r11,_PAGE_ACCESSED@h |
| tlb_miss_kernel_bolted: |
| mfspr r10,SPRN_MAS1 |
| ld r14,PACA_KERNELPGD(r13) |
| srdi r15,r16,44 /* get kernel region */ |
| andi. r15,r15,1 /* Check for vmalloc region */ |
| rlwinm r10,r10,0,16,1 /* Clear TID */ |
| mtspr SPRN_MAS1,r10 |
| bne+ tlb_miss_common_bolted |
| |
| tlb_miss_fault_bolted: |
| /* We need to check if it was an instruction miss */ |
| andi. r10,r11,_PAGE_BAP_UX|_PAGE_BAP_SX |
| bne itlb_miss_fault_bolted |
| dtlb_miss_fault_bolted: |
| tlb_epilog_bolted |
| b exc_data_storage_book3e |
| itlb_miss_fault_bolted: |
| tlb_epilog_bolted |
| b exc_instruction_storage_book3e |
| |
| /* Instruction TLB miss */ |
| START_EXCEPTION(instruction_tlb_miss_bolted) |
| tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0 |
| |
| rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 |
| srdi r15,r16,60 /* get region */ |
| bne- itlb_miss_fault_bolted |
| |
| li r11,_PAGE_PRESENT|_PAGE_BAP_UX /* Base perm */ |
| |
| /* We do the user/kernel test for the PID here along with the RW test |
| */ |
| |
| cmpldi cr0,r15,0 /* Check for user region */ |
| oris r11,r11,_PAGE_ACCESSED@h |
| beq tlb_miss_user_bolted |
| b itlb_miss_kernel_bolted |
| |
| /* |
| * TLB miss handling for e6500 and derivatives, using hardware tablewalk. |
| * |
| * Linear mapping is bolted: no virtual page table or nested TLB misses |
| * Indirect entries in TLB1, hardware loads resulting direct entries |
| * into TLB0 |
| * No HES or NV hint on TLB1, so we need to do software round-robin |
| * No tlbsrx. so we need a spinlock, and we have to deal |
| * with MAS-damage caused by tlbsx |
| * 4K pages only |
| */ |
| |
| START_EXCEPTION(instruction_tlb_miss_e6500) |
| tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0 |
| |
| ld r11,PACA_TCD_PTR(r13) |
| srdi. r15,r16,60 /* get region */ |
| ori r16,r16,1 |
| |
| bne tlb_miss_kernel_e6500 /* user/kernel test */ |
| |
| b tlb_miss_common_e6500 |
| |
| START_EXCEPTION(data_tlb_miss_e6500) |
| tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR |
| |
| ld r11,PACA_TCD_PTR(r13) |
| srdi. r15,r16,60 /* get region */ |
| rldicr r16,r16,0,62 |
| |
| bne tlb_miss_kernel_e6500 /* user vs kernel check */ |
| |
| /* |
| * This is the guts of the TLB miss handler for e6500 and derivatives. |
| * We are entered with: |
| * |
| * r16 = page of faulting address (low bit 0 if data, 1 if instruction) |
| * r15 = crap (free to use) |
| * r14 = page table base |
| * r13 = PACA |
| * r11 = tlb_per_core ptr |
| * r10 = crap (free to use) |
| * r7 = esel_next |
| */ |
| tlb_miss_common_e6500: |
| crmove cr2*4+2,cr0*4+2 /* cr2.eq != 0 if kernel address */ |
| |
| BEGIN_FTR_SECTION /* CPU_FTR_SMT */ |
| /* |
| * Search if we already have an indirect entry for that virtual |
| * address, and if we do, bail out. |
| * |
| * MAS6:IND should be already set based on MAS4 |
| */ |
| lhz r10,PACAPACAINDEX(r13) |
| addi r10,r10,1 |
| crclr cr1*4+eq /* set cr1.eq = 0 for non-recursive */ |
| 1: lbarx r15,0,r11 |
| cmpdi r15,0 |
| bne 2f |
| stbcx. r10,0,r11 |
| bne 1b |
| 3: |
| .subsection 1 |
| 2: cmpd cr1,r15,r10 /* recursive lock due to mcheck/crit/etc? */ |
| beq cr1,3b /* unlock will happen if cr1.eq = 0 */ |
| 10: lbz r15,0(r11) |
| cmpdi r15,0 |
| bne 10b |
| b 1b |
| .previous |
| END_FTR_SECTION_IFSET(CPU_FTR_SMT) |
| |
| lbz r7,TCD_ESEL_NEXT(r11) |
| |
| BEGIN_FTR_SECTION /* CPU_FTR_SMT */ |
| /* |
| * Erratum A-008139 says that we can't use tlbwe to change |
| * an indirect entry in any way (including replacing or |
| * invalidating) if the other thread could be in the process |
| * of a lookup. The workaround is to invalidate the entry |
| * with tlbilx before overwriting. |
| */ |
| |
| rlwinm r10,r7,16,0xff0000 |
| oris r10,r10,MAS0_TLBSEL(1)@h |
| mtspr SPRN_MAS0,r10 |
| isync |
| tlbre |
| mfspr r15,SPRN_MAS1 |
| andis. r15,r15,MAS1_VALID@h |
| beq 5f |
| |
| BEGIN_FTR_SECTION_NESTED(532) |
| mfspr r10,SPRN_MAS8 |
| rlwinm r10,r10,0,0x80000fff /* tgs,tlpid -> sgs,slpid */ |
| mtspr SPRN_MAS5,r10 |
| END_FTR_SECTION_NESTED(CPU_FTR_EMB_HV,CPU_FTR_EMB_HV,532) |
| |
| mfspr r10,SPRN_MAS1 |
| rlwinm r15,r10,0,0x3fff0000 /* tid -> spid */ |
| rlwimi r15,r10,20,0x00000003 /* ind,ts -> sind,sas */ |
| mfspr r10,SPRN_MAS6 |
| mtspr SPRN_MAS6,r15 |
| |
| mfspr r15,SPRN_MAS2 |
| isync |
| PPC_TLBILX_VA(0,R15) |
| isync |
| |
| mtspr SPRN_MAS6,r10 |
| |
| 5: |
| BEGIN_FTR_SECTION_NESTED(532) |
| li r10,0 |
| mtspr SPRN_MAS8,r10 |
| mtspr SPRN_MAS5,r10 |
| END_FTR_SECTION_NESTED(CPU_FTR_EMB_HV,CPU_FTR_EMB_HV,532) |
| |
| tlbsx 0,r16 |
| mfspr r10,SPRN_MAS1 |
| andis. r15,r10,MAS1_VALID@h |
| bne tlb_miss_done_e6500 |
| FTR_SECTION_ELSE |
| mfspr r10,SPRN_MAS1 |
| ALT_FTR_SECTION_END_IFSET(CPU_FTR_SMT) |
| |
| oris r10,r10,MAS1_VALID@h |
| beq cr2,4f |
| rlwinm r10,r10,0,16,1 /* Clear TID */ |
| 4: mtspr SPRN_MAS1,r10 |
| |
| /* Now, we need to walk the page tables. First check if we are in |
| * range. |
| */ |
| rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 |
| bne- tlb_miss_fault_e6500 |
| |
| rldicl r15,r16,64-PGDIR_SHIFT+3,64-PGD_INDEX_SIZE-3 |
| cmpldi cr0,r14,0 |
| clrrdi r15,r15,3 |
| beq- tlb_miss_fault_e6500 /* No PGDIR, bail */ |
| ldx r14,r14,r15 /* grab pgd entry */ |
| |
| rldicl r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3 |
| clrrdi r15,r15,3 |
| cmpdi cr0,r14,0 |
| bge tlb_miss_huge_e6500 /* Bad pgd entry or hugepage; bail */ |
| ldx r14,r14,r15 /* grab pud entry */ |
| |
| rldicl r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3 |
| clrrdi r15,r15,3 |
| cmpdi cr0,r14,0 |
| bge tlb_miss_huge_e6500 |
| ldx r14,r14,r15 /* Grab pmd entry */ |
| |
| mfspr r10,SPRN_MAS0 |
| cmpdi cr0,r14,0 |
| bge tlb_miss_huge_e6500 |
| |
| /* Now we build the MAS for a 2M indirect page: |
| * |
| * MAS 0 : ESEL needs to be filled by software round-robin |
| * MAS 1 : Fully set up |
| * - PID already updated by caller if necessary |
| * - TSIZE for now is base ind page size always |
| * - TID already cleared if necessary |
| * MAS 2 : Default not 2M-aligned, need to be redone |
| * MAS 3+7 : Needs to be done |
| */ |
| |
| ori r14,r14,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT) |
| mtspr SPRN_MAS7_MAS3,r14 |
| |
| clrrdi r15,r16,21 /* make EA 2M-aligned */ |
| mtspr SPRN_MAS2,r15 |
| |
| tlb_miss_huge_done_e6500: |
| lbz r16,TCD_ESEL_MAX(r11) |
| lbz r14,TCD_ESEL_FIRST(r11) |
| rlwimi r10,r7,16,0x00ff0000 /* insert esel_next into MAS0 */ |
| addi r7,r7,1 /* increment esel_next */ |
| mtspr SPRN_MAS0,r10 |
| cmpw r7,r16 |
| iseleq r7,r14,r7 /* if next == last use first */ |
| stb r7,TCD_ESEL_NEXT(r11) |
| |
| tlbwe |
| |
| tlb_miss_done_e6500: |
| .macro tlb_unlock_e6500 |
| BEGIN_FTR_SECTION |
| beq cr1,1f /* no unlock if lock was recursively grabbed */ |
| li r15,0 |
| isync |
| stb r15,0(r11) |
| 1: |
| END_FTR_SECTION_IFSET(CPU_FTR_SMT) |
| .endm |
| |
| tlb_unlock_e6500 |
| tlb_epilog_bolted |
| rfi |
| |
| tlb_miss_huge_e6500: |
| beq tlb_miss_fault_e6500 |
| rlwinm r15,r14,32-_PAGE_PSIZE_SHIFT,0x1e |
| |
| /* |
| * Now we build the MAS for a huge page. |
| * |
| * MAS 0 : ESEL needs to be filled by software round-robin |
| * - can be handled by indirect code |
| * MAS 1 : Need to clear IND and set TSIZE |
| * MAS 2,3+7: Needs to be redone similar to non-tablewalk handler |
| */ |
| |
| mfspr r10,SPRN_MAS1 |
| rlwinm r10,r10,0,~MAS1_IND |
| rlwimi r10,r15,MAS1_TSIZE_SHIFT,MAS1_TSIZE_MASK |
| mtspr SPRN_MAS1,r10 |
| |
| li r10,-0x400 |
| sld r15,r10,r15 /* Generate mask based on size */ |
| and r10,r16,r15 |
| rldicr r15,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT |
| rlwimi r10,r14,32-19,27,31 /* Insert WIMGE */ |
| clrldi r15,r15,PAGE_SHIFT /* Clear crap at the top */ |
| rlwimi r15,r14,32-8,22,25 /* Move in U bits */ |
| mtspr SPRN_MAS2,r10 |
| andi. r10,r14,_PAGE_DIRTY |
| rlwimi r15,r14,32-2,26,31 /* Move in BAP bits */ |
| |
| /* Mask out SW and UW if !DIRTY (XXX optimize this !) */ |
| bne 1f |
| li r10,MAS3_SW|MAS3_UW |
| andc r15,r15,r10 |
| 1: |
| mtspr SPRN_MAS7_MAS3,r15 |
| |
| mfspr r10,SPRN_MAS0 |
| b tlb_miss_huge_done_e6500 |
| |
| tlb_miss_kernel_e6500: |
| ld r14,PACA_KERNELPGD(r13) |
| srdi r15,r16,44 /* get kernel region */ |
| xoris r15,r15,0xc /* Check for vmalloc region */ |
| cmplwi cr1,r15,1 |
| beq+ cr1,tlb_miss_common_e6500 |
| |
| tlb_miss_fault_e6500: |
| tlb_unlock_e6500 |
| /* We need to check if it was an instruction miss */ |
| andi. r16,r16,1 |
| bne itlb_miss_fault_e6500 |
| dtlb_miss_fault_e6500: |
| tlb_epilog_bolted |
| b exc_data_storage_book3e |
| itlb_miss_fault_e6500: |
| tlb_epilog_bolted |
| b exc_instruction_storage_book3e |
| |
| /* |
| * This is the guts of the second-level TLB miss handler for direct |
| * misses. We are entered with: |
| * |
| * r16 = virtual page table faulting address |
| * r15 = region (top 4 bits of address) |
| * r14 = crap (free to use) |
| * r13 = PACA |
| * r12 = TLB exception frame in PACA |
| * r11 = crap (free to use) |
| * r10 = crap (free to use) |
| * |
| * Note that this should only ever be called as a second level handler |
| * with the current scheme when using SW load. |
| * That means we can always get the original fault DEAR at |
| * EX_TLB_DEAR-EX_TLB_SIZE(r12) |
| * |
| * It can be re-entered by the linear mapping miss handler. However, to |
| * avoid too much complication, it will restart the whole fault at level |
| * 0 so we don't care too much about clobbers |
| * |
| * XXX That code was written back when we couldn't clobber r14. We can now, |
| * so we could probably optimize things a bit |
| */ |
| virt_page_table_tlb_miss: |
| /* Are we hitting a kernel page table ? */ |
| srdi r15,r16,60 |
| andi. r10,r15,0x8 |
| |
| /* The cool thing now is that r10 contains 0 for user and 8 for kernel, |
| * and we happen to have the swapper_pg_dir at offset 8 from the user |
| * pgdir in the PACA :-). |
| */ |
| add r11,r10,r13 |
| |
| /* If kernel, we need to clear MAS1 TID */ |
| beq 1f |
| /* XXX replace the RMW cycles with immediate loads + writes */ |
| mfspr r10,SPRN_MAS1 |
| rlwinm r10,r10,0,16,1 /* Clear TID */ |
| mtspr SPRN_MAS1,r10 |
| #ifdef CONFIG_PPC_KUAP |
| b 2f |
| 1: |
| mfspr r10,SPRN_MAS1 |
| rlwinm. r10,r10,0,0x3fff0000 |
| beq- virt_page_table_tlb_miss_fault /* KUAP fault */ |
| 2: |
| #else |
| 1: |
| #endif |
| |
| /* Now, we need to walk the page tables. First check if we are in |
| * range. |
| */ |
| rldicl r10,r16,64-(VPTE_INDEX_SIZE+3),VPTE_INDEX_SIZE+3+4 |
| cmpldi r10,0x80 |
| bne- virt_page_table_tlb_miss_fault |
| |
| /* Get the PGD pointer */ |
| ld r15,PACAPGD(r11) |
| cmpldi cr0,r15,0 |
| beq- virt_page_table_tlb_miss_fault |
| |
| /* Get to PGD entry */ |
| rldicl r11,r16,64-VPTE_PGD_SHIFT,64-PGD_INDEX_SIZE-3 |
| clrrdi r10,r11,3 |
| ldx r15,r10,r15 |
| cmpdi cr0,r15,0 |
| bge virt_page_table_tlb_miss_fault |
| |
| /* Get to PUD entry */ |
| rldicl r11,r16,64-VPTE_PUD_SHIFT,64-PUD_INDEX_SIZE-3 |
| clrrdi r10,r11,3 |
| ldx r15,r10,r15 |
| cmpdi cr0,r15,0 |
| bge virt_page_table_tlb_miss_fault |
| |
| /* Get to PMD entry */ |
| rldicl r11,r16,64-VPTE_PMD_SHIFT,64-PMD_INDEX_SIZE-3 |
| clrrdi r10,r11,3 |
| ldx r15,r10,r15 |
| cmpdi cr0,r15,0 |
| bge virt_page_table_tlb_miss_fault |
| |
| /* Ok, we're all right, we can now create a kernel translation for |
| * a 4K or 64K page from r16 -> r15. |
| */ |
| /* Now we build the MAS: |
| * |
| * MAS 0 : Fully setup with defaults in MAS4 and TLBnCFG |
| * MAS 1 : Almost fully setup |
| * - PID already updated by caller if necessary |
| * - TSIZE for now is base page size always |
| * MAS 2 : Use defaults |
| * MAS 3+7 : Needs to be done |
| * |
| * So we only do MAS 2 and 3 for now... |
| */ |
| clrldi r11,r15,4 /* remove region ID from RPN */ |
| ori r10,r11,1 /* Or-in SR */ |
| |
| srdi r16,r10,32 |
| mtspr SPRN_MAS3,r10 |
| mtspr SPRN_MAS7,r16 |
| |
| tlbwe |
| |
| /* Return to caller, normal case */ |
| TLB_MISS_EPILOG_SUCCESS |
| rfi |
| |
| virt_page_table_tlb_miss_fault: |
| /* If we fault here, things are a little bit tricky. We need to call |
| * either data or instruction store fault, and we need to retrieve |
| * the original fault address and ESR (for data). |
| * |
| * The thing is, we know that in normal circumstances, this is |
| * always called as a second level tlb miss for SW load or as a first |
| * level TLB miss for HW load, so we should be able to peek at the |
| * relevant information in the first exception frame in the PACA. |
| * |
| * However, we do need to double check that, because we may just hit |
| * a stray kernel pointer or a userland attack trying to hit those |
| * areas. If that is the case, we do a data fault. (We can't get here |
| * from an instruction tlb miss anyway). |
| * |
| * Note also that when going to a fault, we must unwind the previous |
| * level as well. Since we are doing that, we don't need to clear or |
| * restore the TLB reservation neither. |
| */ |
| subf r10,r13,r12 |
| cmpldi cr0,r10,PACA_EXTLB+EX_TLB_SIZE |
| bne- virt_page_table_tlb_miss_whacko_fault |
| |
| /* We dig the original DEAR and ESR from slot 0 */ |
| ld r15,EX_TLB_DEAR+PACA_EXTLB(r13) |
| ld r16,EX_TLB_ESR+PACA_EXTLB(r13) |
| |
| /* We check for the "special" ESR value for instruction faults */ |
| cmpdi cr0,r16,-1 |
| beq 1f |
| mtspr SPRN_DEAR,r15 |
| mtspr SPRN_ESR,r16 |
| TLB_MISS_EPILOG_ERROR |
| b exc_data_storage_book3e |
| 1: TLB_MISS_EPILOG_ERROR |
| b exc_instruction_storage_book3e |
| |
| virt_page_table_tlb_miss_whacko_fault: |
| /* The linear fault will restart everything so ESR and DEAR will |
| * not have been clobbered, let's just fault with what we have |
| */ |
| TLB_MISS_EPILOG_ERROR |
| b exc_data_storage_book3e |
| |
| /* |
| * This is the guts of "any" level TLB miss handler for kernel linear |
| * mapping misses. We are entered with: |
| * |
| * |
| * r16 = faulting address |
| * r15 = crap (free to use) |
| * r14 = ESR (data) or -1 (instruction) |
| * r13 = PACA |
| * r12 = TLB exception frame in PACA |
| * r11 = crap (free to use) |
| * r10 = crap (free to use) |
| * |
| * In addition we know that we will not re-enter, so in theory, we could |
| * use a simpler epilog not restoring SRR0/1 etc.. but we'll do that later. |
| * |
| * We also need to be careful about MAS registers here & TLB reservation, |
| * as we know we'll have clobbered them if we interrupt the main TLB miss |
| * handlers in which case we probably want to do a full restart at level |
| * 0 rather than saving / restoring the MAS. |
| * |
| * Note: If we care about performance of that core, we can easily shuffle |
| * a few things around |
| */ |
| tlb_load_linear: |
| /* For now, we assume the linear mapping is contiguous and stops at |
| * linear_map_top. We also assume the size is a multiple of 1G, thus |
| * we only use 1G pages for now. That might have to be changed in a |
| * final implementation, especially when dealing with hypervisors |
| */ |
| __LOAD_PACA_TOC(r11) |
| LOAD_REG_ADDR_ALTTOC(r11, r11, linear_map_top) |
| ld r10,0(r11) |
| tovirt(10,10) |
| cmpld cr0,r16,r10 |
| bge tlb_load_linear_fault |
| |
| /* MAS1 need whole new setup. */ |
| li r15,(BOOK3E_PAGESZ_1GB<<MAS1_TSIZE_SHIFT) |
| oris r15,r15,MAS1_VALID@h /* MAS1 needs V and TSIZE */ |
| mtspr SPRN_MAS1,r15 |
| |
| /* Already somebody there ? */ |
| PPC_TLBSRX_DOT(0,R16) |
| beq tlb_load_linear_done |
| |
| /* Now we build the remaining MAS. MAS0 and 2 should be fine |
| * with their defaults, which leaves us with MAS 3 and 7. The |
| * mapping is linear, so we just take the address, clear the |
| * region bits, and or in the permission bits which are currently |
| * hard wired |
| */ |
| clrrdi r10,r16,30 /* 1G page index */ |
| clrldi r10,r10,4 /* clear region bits */ |
| ori r10,r10,MAS3_SR|MAS3_SW|MAS3_SX |
| |
| srdi r16,r10,32 |
| mtspr SPRN_MAS3,r10 |
| mtspr SPRN_MAS7,r16 |
| |
| tlbwe |
| |
| tlb_load_linear_done: |
| /* We use the "error" epilog for success as we do want to |
| * restore to the initial faulting context, whatever it was. |
| * We do that because we can't resume a fault within a TLB |
| * miss handler, due to MAS and TLB reservation being clobbered. |
| */ |
| TLB_MISS_EPILOG_ERROR |
| rfi |
| |
| tlb_load_linear_fault: |
| /* We keep the DEAR and ESR around, this shouldn't have happened */ |
| cmpdi cr0,r14,-1 |
| beq 1f |
| TLB_MISS_EPILOG_ERROR_SPECIAL |
| b exc_data_storage_book3e |
| 1: TLB_MISS_EPILOG_ERROR_SPECIAL |
| b exc_instruction_storage_book3e |
