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diff --git a/arch/powerpc/mm/nohash/tlb_low_64e.S b/arch/powerpc/mm/nohash/tlb_low_64e.S
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+++ b/arch/powerpc/mm/nohash/tlb_low_64e.S
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+/* 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
+ tlbilxva 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
+ li r10,1
+ andi. r15,r14,HUGEPD_SHIFT_MASK@l /* r15 = psize */
+ rldimi r14,r10,63,0 /* Set PD_HUGE */
+ xor r14,r14,r15 /* Clear size bits */
+ ldx r14,0,r14
+
+ /*
+ * 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
+ */
+
+ subi r15,r15,10 /* Convert psize to tsize */
+ 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
+
+/**********************************************************************
+ * *
+ * TLB miss handling for Book3E with TLB reservation and HES support *
+ * *
+ **********************************************************************/
+
+
+/* Data TLB miss */
+ START_EXCEPTION(data_tlb_miss)
+ TLB_MISS_PROLOG
+
+ /* Now we handle the fault proper. We only save DEAR in normal
+ * fault case since that's the only interesting values here.
+ * We could probably also optimize by not saving SRR0/1 in the
+ * linear mapping case but I'll leave that for later
+ */
+ mfspr r14,SPRN_ESR
+ mfspr r16,SPRN_DEAR /* get faulting address */
+ srdi r15,r16,44 /* get region */
+ xoris r15,r15,0xc
+ cmpldi cr0,r15,0 /* linear mapping ? */
+ beq tlb_load_linear /* yes -> go to linear map load */
+ cmpldi cr1,r15,1 /* vmalloc mapping ? */
+
+ /* The page tables are mapped virtually linear. At this point, though,
+ * we don't know whether we are trying to fault in a first level
+ * virtual address or a virtual page table address. We can get that
+ * from bit 0x1 of the region ID which we have set for a page table
+ */
+ andis. r10,r15,0x1
+ bne- virt_page_table_tlb_miss
+
+ std r14,EX_TLB_ESR(r12); /* save ESR */
+ std r16,EX_TLB_DEAR(r12); /* save DEAR */
+
+ /* We need _PAGE_PRESENT and _PAGE_ACCESSED set */
+ li r11,_PAGE_PRESENT
+ oris r11,r11,_PAGE_ACCESSED@h
+
+ /* We do the user/kernel test for the PID here along with the RW test
+ */
+ srdi. r15,r16,60 /* Check for user region */
+
+ /* 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
+ */
+ rlwimi r11,r14,32-19,27,27
+ rlwimi r11,r14,32-16,19,19
+ beq normal_tlb_miss_user
+ /* XXX replace the RMW cycles with immediate loads + writes */
+1: mfspr r10,SPRN_MAS1
+ rlwinm r10,r10,0,16,1 /* Clear TID */
+ mtspr SPRN_MAS1,r10
+ beq+ cr1,normal_tlb_miss
+
+ /* We got a crappy address, just fault with whatever DEAR and ESR
+ * are here
+ */
+ TLB_MISS_EPILOG_ERROR
+ b exc_data_storage_book3e
+
+/* Instruction TLB miss */
+ START_EXCEPTION(instruction_tlb_miss)
+ TLB_MISS_PROLOG
+
+ /* If we take a recursive fault, the second level handler may need
+ * to know whether we are handling a data or instruction fault in
+ * order to get to the right store fault handler. We provide that
+ * info by writing a crazy value in ESR in our exception frame
+ */
+ li r14,-1 /* store to exception frame is done later */
+
+ /* Now we handle the fault proper. We only save DEAR in the non
+ * linear mapping case since we know the linear mapping case will
+ * not re-enter. We could indeed optimize and also not save SRR0/1
+ * in the linear mapping case but I'll leave that for later
+ *
+ * Faulting address is SRR0 which is already in r16
+ */
+ srdi r15,r16,44 /* get region */
+ xoris r15,r15,0xc
+ cmpldi cr0,r15,0 /* linear mapping ? */
+ beq tlb_load_linear /* yes -> go to linear map load */
+ cmpldi cr1,r15,1 /* vmalloc mapping ? */
+
+ /* We do the user/kernel test for the PID here along with the RW test
+ */
+ li r11,_PAGE_PRESENT|_PAGE_BAP_UX /* Base perm */
+ oris r11,r11,_PAGE_ACCESSED@h
+
+ srdi. r15,r16,60 /* Check for user region */
+ std r14,EX_TLB_ESR(r12) /* write crazy -1 to frame */
+ beq normal_tlb_miss_user
+
+ li r11,_PAGE_PRESENT|_PAGE_BAP_SX /* Base perm */
+ oris r11,r11,_PAGE_ACCESSED@h
+ /* 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
+ beq+ cr1,normal_tlb_miss
+
+ /* We got a crappy address, just fault */
+ TLB_MISS_EPILOG_ERROR
+ b exc_instruction_storage_book3e
+
+/*
+ * This is the guts of the first-level TLB miss handler for direct
+ * misses. We are entered with:
+ *
+ * r16 = faulting address
+ * r15 = region ID
+ * r14 = crap (free to use)
+ * r13 = PACA
+ * r12 = TLB exception frame in PACA
+ * r11 = PTE permission mask
+ * r10 = crap (free to use)
+ */
+normal_tlb_miss_user:
+#ifdef CONFIG_PPC_KUAP
+ mfspr r14,SPRN_MAS1
+ rlwinm. r14,r14,0,0x3fff0000
+ beq- normal_tlb_miss_access_fault /* KUAP fault */
+#endif
+normal_tlb_miss:
+ /* So we first construct the page table address. We do that by
+ * shifting the bottom of the address (not the region ID) by
+ * PAGE_SHIFT-3, clearing the bottom 3 bits (get a PTE ptr) and
+ * or'ing the fourth high bit.
+ *
+ * NOTE: For 64K pages, we do things slightly differently in
+ * order to handle the weird page table format used by linux
+ */
+ srdi r15,r16,44
+ oris r10,r15,0x1
+ rldicl r14,r16,64-(PAGE_SHIFT-3),PAGE_SHIFT-3+4
+ sldi r15,r10,44
+ clrrdi r14,r14,19
+ or r10,r15,r14
+
+ ld r14,0(r10)
+
+finish_normal_tlb_miss:
+ /* Check if required permissions are met */
+ andc. r15,r11,r14
+ bne- normal_tlb_miss_access_fault
+
+ /* 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
+ *
+ * TODO: mix up code below for better scheduling
+ */
+ clrrdi r10,r16,12 /* Clear low crap in EA */
+ rlwimi r10,r14,32-19,27,31 /* Insert WIMGE */
+ mtspr SPRN_MAS2,r10
+
+ /* Check page size, if not standard, update MAS1 */
+ rldicl r10,r14,64-8,64-8
+ cmpldi cr0,r10,BOOK3E_PAGESZ_4K
+ beq- 1f
+ mfspr r11,SPRN_MAS1
+ rlwimi r11,r14,31,21,24
+ rlwinm r11,r11,0,21,19
+ mtspr SPRN_MAS1,r11
+1:
+ /* Move RPN in position */
+ rldicr r11,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT
+ clrldi r15,r11,12 /* Clear crap at the top */
+ rlwimi r15,r14,32-8,22,25 /* Move in U bits */
+ rlwimi r15,r14,32-2,26,31 /* Move in BAP bits */
+
+ /* Mask out SW and UW if !DIRTY (XXX optimize this !) */
+ andi. r11,r14,_PAGE_DIRTY
+ bne 1f
+ li r11,MAS3_SW|MAS3_UW
+ andc r15,r15,r11
+1:
+ srdi r16,r15,32
+ mtspr SPRN_MAS3,r15
+ mtspr SPRN_MAS7,r16
+
+ tlbwe
+
+normal_tlb_miss_done:
+ /* We don't bother with restoring DEAR or ESR since we know we are
+ * level 0 and just going back to userland. They are only needed
+ * if you are going to take an access fault
+ */
+ TLB_MISS_EPILOG_SUCCESS
+ rfi
+
+normal_tlb_miss_access_fault:
+ /* We need to check if it was an instruction miss */
+ andi. r10,r11,_PAGE_BAP_UX
+ bne 1f
+ ld r14,EX_TLB_DEAR(r12)
+ ld r15,EX_TLB_ESR(r12)
+ mtspr SPRN_DEAR,r14
+ mtspr SPRN_ESR,r15
+ TLB_MISS_EPILOG_ERROR
+ b exc_data_storage_book3e
+1: TLB_MISS_EPILOG_ERROR
+ 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
+
+
+/**************************************************************
+ * *
+ * TLB miss handling for Book3E with hw page table support *
+ * *
+ **************************************************************/
+
+
+/* Data TLB miss */
+ START_EXCEPTION(data_tlb_miss_htw)
+ TLB_MISS_PROLOG
+
+ /* Now we handle the fault proper. We only save DEAR in normal
+ * fault case since that's the only interesting values here.
+ * We could probably also optimize by not saving SRR0/1 in the
+ * linear mapping case but I'll leave that for later
+ */
+ mfspr r14,SPRN_ESR
+ mfspr r16,SPRN_DEAR /* get faulting address */
+ srdi r11,r16,44 /* get region */
+ xoris r11,r11,0xc
+ cmpldi cr0,r11,0 /* linear mapping ? */
+ beq tlb_load_linear /* yes -> go to linear map load */
+ cmpldi cr1,r11,1 /* vmalloc mapping ? */
+
+ /* We do the user/kernel test for the PID here along with the RW test
+ */
+ srdi. r11,r16,60 /* Check for user region */
+ ld r15,PACAPGD(r13) /* Load user pgdir */
+ beq htw_tlb_miss
+
+ /* XXX replace the RMW cycles with immediate loads + writes */
+1: mfspr r10,SPRN_MAS1
+ rlwinm r10,r10,0,16,1 /* Clear TID */
+ mtspr SPRN_MAS1,r10
+ ld r15,PACA_KERNELPGD(r13) /* Load kernel pgdir */
+ beq+ cr1,htw_tlb_miss
+
+ /* We got a crappy address, just fault with whatever DEAR and ESR
+ * are here
+ */
+ TLB_MISS_EPILOG_ERROR
+ b exc_data_storage_book3e
+
+/* Instruction TLB miss */
+ START_EXCEPTION(instruction_tlb_miss_htw)
+ TLB_MISS_PROLOG
+
+ /* If we take a recursive fault, the second level handler may need
+ * to know whether we are handling a data or instruction fault in
+ * order to get to the right store fault handler. We provide that
+ * info by keeping a crazy value for ESR in r14
+ */
+ li r14,-1 /* store to exception frame is done later */
+
+ /* Now we handle the fault proper. We only save DEAR in the non
+ * linear mapping case since we know the linear mapping case will
+ * not re-enter. We could indeed optimize and also not save SRR0/1
+ * in the linear mapping case but I'll leave that for later
+ *
+ * Faulting address is SRR0 which is already in r16
+ */
+ srdi r11,r16,44 /* get region */
+ xoris r11,r11,0xc
+ cmpldi cr0,r11,0 /* linear mapping ? */
+ beq tlb_load_linear /* yes -> go to linear map load */
+ cmpldi cr1,r11,1 /* vmalloc mapping ? */
+
+ /* We do the user/kernel test for the PID here along with the RW test
+ */
+ srdi. r11,r16,60 /* Check for user region */
+ ld r15,PACAPGD(r13) /* Load user pgdir */
+ beq htw_tlb_miss
+
+ /* XXX replace the RMW cycles with immediate loads + writes */
+1: mfspr r10,SPRN_MAS1
+ rlwinm r10,r10,0,16,1 /* Clear TID */
+ mtspr SPRN_MAS1,r10
+ ld r15,PACA_KERNELPGD(r13) /* Load kernel pgdir */
+ beq+ htw_tlb_miss
+
+ /* We got a crappy address, just fault */
+ TLB_MISS_EPILOG_ERROR
+ 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 = PGD pointer
+ * r14 = ESR
+ * r13 = PACA
+ * r12 = TLB exception frame in PACA
+ * r11 = crap (free to use)
+ * r10 = crap (free to use)
+ *
+ * It can be re-entered by the linear mapping miss handler. However, to
+ * avoid too much complication, it will save/restore things for us
+ */
+htw_tlb_miss:
+#ifdef CONFIG_PPC_KUAP
+ mfspr r10,SPRN_MAS1
+ rlwinm. r10,r10,0,0x3fff0000
+ beq- htw_tlb_miss_fault /* KUAP fault */
+#endif
+ /* Search if we already have a TLB entry for that virtual address, and
+ * if we do, bail out.
+ *
+ * MAS1:IND should be already set based on MAS4
+ */
+ PPC_TLBSRX_DOT(0,R16)
+ beq htw_tlb_miss_done
+
+ /* 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- htw_tlb_miss_fault
+
+ /* Get the PGD pointer */
+ cmpldi cr0,r15,0
+ beq- htw_tlb_miss_fault
+
+ /* Get to PGD entry */
+ rldicl r11,r16,64-(PGDIR_SHIFT-3),64-PGD_INDEX_SIZE-3
+ clrrdi r10,r11,3
+ ldx r15,r10,r15
+ cmpdi cr0,r15,0
+ bge htw_tlb_miss_fault
+
+ /* Get to PUD entry */
+ rldicl r11,r16,64-(PUD_SHIFT-3),64-PUD_INDEX_SIZE-3
+ clrrdi r10,r11,3
+ ldx r15,r10,r15
+ cmpdi cr0,r15,0
+ bge htw_tlb_miss_fault
+
+ /* Get to PMD entry */
+ rldicl r11,r16,64-(PMD_SHIFT-3),64-PMD_INDEX_SIZE-3
+ clrrdi r10,r11,3
+ ldx r15,r10,r15
+ cmpdi cr0,r15,0
+ bge htw_tlb_miss_fault
+
+ /* Ok, we're all right, we can now create an indirect entry for
+ * a 1M or 256M page.
+ *
+ * The last trick is now that because we use "half" pages for
+ * the HTW (1M IND is 2K and 256M IND is 32K) we need to account
+ * for an added LSB bit to the RPN. For 64K pages, there is no
+ * problem as we already use 32K arrays (half PTE pages), but for
+ * 4K page we need to extract a bit from the virtual address and
+ * insert it into the "PA52" bit of the RPN.
+ */
+ rlwimi r15,r16,32-9,20,20
+ /* 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 ind page size always
+ * MAS 2 : Use defaults
+ * MAS 3+7 : Needs to be done
+ */
+ ori r10,r15,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT)
+
+ srdi r16,r10,32
+ mtspr SPRN_MAS3,r10
+ mtspr SPRN_MAS7,r16
+
+ tlbwe
+
+htw_tlb_miss_done:
+ /* We don't bother with restoring DEAR or ESR since we know we are
+ * level 0 and just going back to userland. They are only needed
+ * if you are going to take an access fault
+ */
+ TLB_MISS_EPILOG_SUCCESS
+ rfi
+
+htw_tlb_miss_fault:
+ /* We need to check if it was an instruction miss. We know this
+ * though because r14 would contain -1
+ */
+ cmpdi cr0,r14,-1
+ beq 1f
+ mtspr SPRN_DEAR,r16
+ mtspr SPRN_ESR,r14
+ TLB_MISS_EPILOG_ERROR
+ b exc_data_storage_book3e
+1: TLB_MISS_EPILOG_ERROR
+ b exc_instruction_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