tlb_low_64e.S 35.4 KB
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/*
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 *  Low level TLB miss handlers for Book3E
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 *
 *  Copyright (C) 2008-2009
 *      Ben. Herrenschmidt (benh@kernel.crashing.org), IBM Corp.
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 */

#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/pgtable.h>
#include <asm/exception-64e.h>
#include <asm/ppc-opcode.h>
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#include <asm/kvm_asm.h>
#include <asm/kvm_booke_hv_asm.h>
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#ifdef CONFIG_PPC_64K_PAGES
#define VPTE_PMD_SHIFT	(PTE_INDEX_SIZE+1)
#else
#define VPTE_PMD_SHIFT	(PTE_INDEX_SIZE)
#endif
#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)

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/**********************************************************************
 *                                                                    *
 * TLB miss handling for Book3E with a bolted linear mapping          *
 * No virtual page table, no nested TLB misses                        *
 *                                                                    *
 **********************************************************************/

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/*
 * 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.
 */
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.macro tlb_prolog_bolted intnum addr
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	mtspr	SPRN_SPRG_GEN_SCRATCH,r12
	mfspr	r12,SPRN_SPRG_TLB_EXFRAME
	std	r13,EX_TLB_R13(r12)
	std	r10,EX_TLB_R10(r12)
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	mfspr	r13,SPRN_SPRG_PACA
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	mfcr	r10
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	std	r11,EX_TLB_R11(r12)
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#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
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	std	r16,EX_TLB_R16(r12)
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	mfspr	r16,\addr		/* get faulting address */
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	std	r14,EX_TLB_R14(r12)
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	ld	r14,PACAPGD(r13)
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	std	r15,EX_TLB_R15(r12)
	std	r10,EX_TLB_CR(r12)
	TLB_MISS_PROLOG_STATS
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.endm

.macro tlb_epilog_bolted
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	ld	r14,EX_TLB_CR(r12)
	ld	r10,EX_TLB_R10(r12)
	ld	r11,EX_TLB_R11(r12)
	ld	r13,EX_TLB_R13(r12)
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	mtcr	r14
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	ld	r14,EX_TLB_R14(r12)
	ld	r15,EX_TLB_R15(r12)
	TLB_MISS_RESTORE_STATS
	ld	r16,EX_TLB_R16(r12)
	mfspr	r12,SPRN_SPRG_GEN_SCRATCH
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.endm

/* Data TLB miss */
	START_EXCEPTION(data_tlb_miss_bolted)
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	tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR
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	/* 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
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	bne-	dtlb_miss_fault_bolted	/* Bail if fault addr is invalid */
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	rlwinm	r10,r11,32-19,27,27
	rlwimi	r10,r11,32-16,19,19
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	cmpwi	r15,0			/* user vs kernel check */
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	ori	r10,r10,_PAGE_PRESENT
	oris	r11,r10,_PAGE_ACCESSED@h

	TLB_MISS_STATS_SAVE_INFO_BOLTED
	bne	tlb_miss_kernel_bolted

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
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	beq	tlb_miss_fault_bolted	/* No PGDIR, bail */
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BEGIN_MMU_FTR_SECTION
	/* Set the TLB reservation and search for existing entry. Then load
	 * the entry.
	 */
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	PPC_TLBSRX_DOT(0,R16)
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	ldx	r14,r14,r15		/* grab pgd entry */
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	beq	tlb_miss_done_bolted	/* tlb exists already, bail */
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MMU_FTR_SECTION_ELSE
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	ldx	r14,r14,r15		/* grab pgd entry */
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ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBRSRV)

#ifndef CONFIG_PPC_64K_PAGES
	rldicl	r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3
	clrrdi	r15,r15,3
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	cmpdi	cr0,r14,0
	bge	tlb_miss_fault_bolted	/* Bad pgd entry or hugepage; bail */
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	ldx	r14,r14,r15		/* grab pud entry */
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#endif /* CONFIG_PPC_64K_PAGES */

	rldicl	r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3
	clrrdi	r15,r15,3
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	cmpdi	cr0,r14,0
	bge	tlb_miss_fault_bolted
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	ldx	r14,r14,r15		/* Grab pmd entry */
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	rldicl	r15,r16,64-PAGE_SHIFT+3,64-PTE_INDEX_SIZE-3
	clrrdi	r15,r15,3
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	cmpdi	cr0,r14,0
	bge	tlb_miss_fault_bolted
	ldx	r14,r14,r15		/* Grab PTE, normal (!huge) page */
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	/* 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

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tlb_miss_done_bolted:
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	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_NORM_OK)
	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)
	cmpldi	cr0,r15,8		/* Check for vmalloc region */
	rlwinm	r10,r10,0,16,1		/* Clear TID */
	mtspr	SPRN_MAS1,r10
	beq+	tlb_miss_common_bolted

tlb_miss_fault_bolted:
	/* We need to check if it was an instruction miss */
	andi.	r10,r11,_PAGE_EXEC|_PAGE_BAP_SX
	bne	itlb_miss_fault_bolted
dtlb_miss_fault_bolted:
	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
	tlb_epilog_bolted
	b	exc_data_storage_book3e
itlb_miss_fault_bolted:
	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT)
	tlb_epilog_bolted
	b	exc_instruction_storage_book3e

/* Instruction TLB miss */
	START_EXCEPTION(instruction_tlb_miss_bolted)
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	tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0
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	rldicl.	r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4
	srdi	r15,r16,60		/* get region */
	TLB_MISS_STATS_SAVE_INFO_BOLTED
	bne-	itlb_miss_fault_bolted

	li	r11,_PAGE_PRESENT|_PAGE_EXEC	/* 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_common_bolted
	b	itlb_miss_kernel_bolted
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#ifdef CONFIG_PPC_FSL_BOOK3E
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/*
 * 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

	TLB_MISS_STATS_SAVE_INFO_BOLTED
	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

	TLB_MISS_STATS_SAVE_INFO_BOLTED
	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
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 * r10 = crap (free to use)
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 */
tlb_miss_common_e6500:
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	crmove	cr2*4+2,cr0*4+2		/* cr2.eq != 0 if kernel address */

BEGIN_FTR_SECTION		/* CPU_FTR_SMT */
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	/*
	 * 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
	 */
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1:	lbarx	r15,0,r11
	lhz	r10,PACAPACAINDEX(r13)
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	cmpdi	r15,0
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	cmpdi	cr1,r15,1	/* set cr1.eq = 0 for non-recursive */
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	addi	r10,r10,1
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	bne	2f
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	stbcx.	r10,0,r11
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	bne	1b
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	.subsection 1
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2:	cmpd	cr1,r15,r10	/* recursive lock due to mcheck/crit/etc? */
	beq	cr1,3b		/* unlock will happen if cr1.eq = 0 */
	lbz	r15,0(r11)
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	cmpdi	r15,0
	bne	2b
	b	1b
	.previous

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	/*
	 * 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.
	 */

	lbz	r15,TCD_ESEL_NEXT(r11)
	rlwinm	r10,r15,16,0xff0000
	oris	r10,r10,MAS0_TLBSEL(1)@h
	mtspr	SPRN_MAS0,r10
	isync
	tlbre
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	mfspr	r15,SPRN_MAS1
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	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)
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	mfspr	r10,SPRN_MAS1
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	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
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	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
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	bne	tlb_miss_done_e6500
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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
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	/* 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_fault_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_fault_e6500
	ldx	r14,r14,r15		/* Grab pmd entry */

	mfspr	r10,SPRN_MAS0
	cmpdi	cr0,r14,0
	bge	tlb_miss_fault_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

	lbz	r15,TCD_ESEL_NEXT(r11)
	lbz	r16,TCD_ESEL_MAX(r11)
	lbz	r14,TCD_ESEL_FIRST(r11)
	rlwimi	r10,r15,16,0x00ff0000	/* insert esel_next into MAS0 */
	addi	r15,r15,1		/* increment esel_next */
	mtspr	SPRN_MAS0,r10
	cmpw	r15,r16
	iseleq	r15,r14,r15		/* if next == last use first */
	stb	r15,TCD_ESEL_NEXT(r11)

	tlbwe

tlb_miss_done_e6500:
	.macro	tlb_unlock_e6500
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BEGIN_FTR_SECTION
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	beq	cr1,1f		/* no unlock if lock was recursively grabbed */
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	li	r15,0
	isync
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	stb	r15,0(r11)
1:
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END_FTR_SECTION_IFSET(CPU_FTR_SMT)
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	.endm

	tlb_unlock_e6500
	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_NORM_OK)
	tlb_epilog_bolted
	rfi

tlb_miss_kernel_e6500:
	ld	r14,PACA_KERNELPGD(r13)
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	cmpldi	cr1,r15,8		/* Check for vmalloc region */
	beq+	cr1,tlb_miss_common_e6500
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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_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
	tlb_epilog_bolted
	b	exc_data_storage_book3e
itlb_miss_fault_e6500:
	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT)
	tlb_epilog_bolted
	b	exc_instruction_storage_book3e
477
#endif /* CONFIG_PPC_FSL_BOOK3E */
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/**********************************************************************
 *                                                                    *
 * 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,r16,60		/* get region */
	cmpldi	cr0,r15,0xc		/* linear mapping ? */
	TLB_MISS_STATS_SAVE_INFO
	beq	tlb_load_linear		/* yes -> go to linear map load */

	/* 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
	 */
	andi.	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
	 */
	cmpldi	cr0,r15,0		/* 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
	/* XXX replace the RMW cycles with immediate loads + writes */
1:	mfspr	r10,SPRN_MAS1
	cmpldi	cr0,r15,8		/* Check for vmalloc region */
	rlwinm	r10,r10,0,16,1		/* Clear TID */
	mtspr	SPRN_MAS1,r10
	beq+	normal_tlb_miss

	/* We got a crappy address, just fault with whatever DEAR and ESR
	 * are here
	 */
	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
	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,r16,60		/* get region */
	cmpldi	cr0,r15,0xc		/* linear mapping ? */
	TLB_MISS_STATS_SAVE_INFO
	beq	tlb_load_linear		/* yes -> go to linear map load */

	/* We do the user/kernel test for the PID here along with the RW test
	 */
580
	li	r11,_PAGE_PRESENT|_PAGE_EXEC	/* Base perm */
581 582 583 584 585
	oris	r11,r11,_PAGE_ACCESSED@h

	cmpldi	cr0,r15,0			/* Check for user region */
	std	r14,EX_TLB_ESR(r12)		/* write crazy -1 to frame */
	beq	normal_tlb_miss
586 587 588

	li	r11,_PAGE_PRESENT|_PAGE_BAP_SX	/* Base perm */
	oris	r11,r11,_PAGE_ACCESSED@h
589
	/* XXX replace the RMW cycles with immediate loads + writes */
590
	mfspr	r10,SPRN_MAS1
591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638
	cmpldi	cr0,r15,8			/* Check for vmalloc region */
	rlwinm	r10,r10,0,16,1			/* Clear TID */
	mtspr	SPRN_MAS1,r10
	beq+	normal_tlb_miss

	/* We got a crappy address, just fault */
	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_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:
	/* 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
	 */
	ori	r10,r15,0x1
#ifdef CONFIG_PPC_64K_PAGES
	/* For the top bits, 16 bytes per PTE */
	rldicl	r14,r16,64-(PAGE_SHIFT-4),PAGE_SHIFT-4+4
	/* Now create the bottom bits as 0 in position 0x8000 and
	 * the rest calculated for 8 bytes per PTE
	 */
	rldicl	r15,r16,64-(PAGE_SHIFT-3),64-15
	/* Insert the bottom bits in */
	rlwimi	r14,r15,0,16,31
#else
	rldicl	r14,r16,64-(PAGE_SHIFT-3),PAGE_SHIFT-3+4
#endif
	sldi	r15,r10,60
	clrrdi	r14,r14,3
	or	r10,r15,r14

639
BEGIN_MMU_FTR_SECTION
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	/* Set the TLB reservation and search for existing entry. Then load
641 642
	 * the entry.
	 */
643
	PPC_TLBSRX_DOT(0,R16)
644 645
	ld	r14,0(r10)
	beq	normal_tlb_miss_done
646 647 648
MMU_FTR_SECTION_ELSE
	ld	r14,0(r10)
ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBRSRV)
649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694

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	r11,r16,12		/* Clear low crap in EA */
	rlwimi	r11,r14,32-19,27,31	/* Insert WIMGE */
	mtspr	SPRN_MAS2,r11

	/* Check page size, if not standard, update MAS1 */
	rldicl	r11,r14,64-8,64-8
#ifdef CONFIG_PPC_64K_PAGES
	cmpldi	cr0,r11,BOOK3E_PAGESZ_64K
#else
	cmpldi	cr0,r11,BOOK3E_PAGESZ_4K
#endif
	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
695 696 697 698 699 700 701 702
1:
BEGIN_MMU_FTR_SECTION
	srdi	r16,r15,32
	mtspr	SPRN_MAS3,r15
	mtspr	SPRN_MAS7,r16
MMU_FTR_SECTION_ELSE
	mtspr	SPRN_MAS7_MAS3,r15
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
703 704 705 706 707 708 709 710 711 712 713 714 715 716

	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_STATS_X(MMSTAT_TLB_MISS_NORM_OK)
	TLB_MISS_EPILOG_SUCCESS
	rfi

normal_tlb_miss_access_fault:
	/* We need to check if it was an instruction miss */
717
	andi.	r10,r11,_PAGE_EXEC
718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771
	bne	1f
	ld	r14,EX_TLB_DEAR(r12)
	ld	r15,EX_TLB_ESR(r12)
	mtspr	SPRN_DEAR,r14
	mtspr	SPRN_ESR,r15
	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
	TLB_MISS_EPILOG_ERROR
	b	exc_data_storage_book3e
1:	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_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 = 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 ? */
	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
1:
772
BEGIN_MMU_FTR_SECTION
773 774 775
	/* Search if we already have a TLB entry for that virtual address, and
	 * if we do, bail out.
	 */
776
	PPC_TLBSRX_DOT(0,R16)
777
	beq	virt_page_table_tlb_miss_done
778
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_TLBRSRV)
779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794

	/* 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
	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
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	cmpdi	cr0,r15,0
	bge	virt_page_table_tlb_miss_fault
797 798 799 800 801 802

#ifndef CONFIG_PPC_64K_PAGES
	/* Get to PUD entry */
	rldicl	r11,r16,64-VPTE_PUD_SHIFT,64-PUD_INDEX_SIZE-3
	clrrdi	r10,r11,3
	ldx	r15,r10,r15
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	cmpdi	cr0,r15,0
	bge	virt_page_table_tlb_miss_fault
805 806 807 808 809 810
#endif /* CONFIG_PPC_64K_PAGES */

	/* Get to PMD entry */
	rldicl	r11,r16,64-VPTE_PMD_SHIFT,64-PMD_INDEX_SIZE-3
	clrrdi	r10,r11,3
	ldx	r15,r10,r15
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	cmpdi	cr0,r15,0
	bge	virt_page_table_tlb_miss_fault
813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829

	/* 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 */
830 831 832 833 834 835

BEGIN_MMU_FTR_SECTION
	srdi	r16,r10,32
	mtspr	SPRN_MAS3,r10
	mtspr	SPRN_MAS7,r16
MMU_FTR_SECTION_ELSE
836
	mtspr	SPRN_MAS7_MAS3,r10
837
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
838 839 840

	tlbwe

841
BEGIN_MMU_FTR_SECTION
842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864
virt_page_table_tlb_miss_done:

	/* We have overriden MAS2:EPN but currently our primary TLB miss
	 * handler will always restore it so that should not be an issue,
	 * if we ever optimize the primary handler to not write MAS2 on
	 * some cases, we'll have to restore MAS2:EPN here based on the
	 * original fault's DEAR. If we do that we have to modify the
	 * ITLB miss handler to also store SRR0 in the exception frame
	 * as DEAR.
	 *
	 * However, one nasty thing we did is we cleared the reservation
	 * (well, potentially we did). We do a trick here thus if we
	 * are not a level 0 exception (we interrupted the TLB miss) we
	 * offset the return address by -4 in order to replay the tlbsrx
	 * instruction there
	 */
	subf	r10,r13,r12
	cmpldi	cr0,r10,PACA_EXTLB+EX_TLB_SIZE
	bne-	1f
	ld	r11,PACA_EXTLB+EX_TLB_SIZE+EX_TLB_SRR0(r13)
	addi	r10,r11,-4
	std	r10,PACA_EXTLB+EX_TLB_SIZE+EX_TLB_SRR0(r13)
1:
865
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_TLBRSRV)
866 867 868 869 870 871 872
	/* Return to caller, normal case */
	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_PT_OK);
	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
L
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	 * either data or instruction store fault, and we need to retrieve
874 875 876 877 878
	 * 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
879
	 * relevant information in the first exception frame in the PACA.
880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026
	 *
	 * 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_STATS_D(MMSTAT_TLB_MISS_PT_FAULT);
	TLB_MISS_EPILOG_ERROR
	b	exc_data_storage_book3e
1:	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_PT_FAULT);
	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_STATS_X(MMSTAT_TLB_MISS_PT_FAULT);
	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,r16,60		/* get region */
	cmpldi	cr0,r11,0xc		/* linear mapping ? */
	TLB_MISS_STATS_SAVE_INFO
	beq	tlb_load_linear		/* yes -> go to linear map load */

	/* We do the user/kernel test for the PID here along with the RW test
	 */
	cmpldi	cr0,r11,0		/* 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
	cmpldi	cr0,r11,8		/* Check for vmalloc region */
	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 with whatever DEAR and ESR
	 * are here
	 */
	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
	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,r16,60		/* get region */
	cmpldi	cr0,r11,0xc		/* linear mapping ? */
	TLB_MISS_STATS_SAVE_INFO
	beq	tlb_load_linear		/* yes -> go to linear map load */

	/* We do the user/kernel test for the PID here along with the RW test
	 */
	cmpldi	cr0,r11,0			/* 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
	cmpldi	cr0,r11,8			/* Check for vmalloc region */
	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_STATS_I(MMSTAT_TLB_MISS_NORM_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:
	/* 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
	 */
1027
	PPC_TLBSRX_DOT(0,R16)
1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043
	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
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Becky Bruce 已提交
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	cmpdi	cr0,r15,0
	bge	htw_tlb_miss_fault
1046 1047 1048 1049 1050 1051

#ifndef CONFIG_PPC_64K_PAGES
	/* Get to PUD entry */
	rldicl	r11,r16,64-(PUD_SHIFT-3),64-PUD_INDEX_SIZE-3
	clrrdi	r10,r11,3
	ldx	r15,r10,r15
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	cmpdi	cr0,r15,0
	bge	htw_tlb_miss_fault
1054 1055 1056 1057 1058 1059
#endif /* CONFIG_PPC_64K_PAGES */

	/* Get to PMD entry */
	rldicl	r11,r16,64-(PMD_SHIFT-3),64-PMD_INDEX_SIZE-3
	clrrdi	r10,r11,3
	ldx	r15,r10,r15
B
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	cmpdi	cr0,r15,0
	bge	htw_tlb_miss_fault
1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089

	/* 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.
	 */
#ifndef CONFIG_PPC_64K_PAGES
	rlwimi	r15,r16,32-9,20,20
#endif
	/* 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
	 */
#ifdef CONFIG_PPC_64K_PAGES
	ori	r10,r15,(BOOK3E_PAGESZ_64K << MAS3_SPSIZE_SHIFT)
#else
	ori	r10,r15,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT)
#endif
1090 1091 1092 1093 1094 1095

BEGIN_MMU_FTR_SECTION
	srdi	r16,r10,32
	mtspr	SPRN_MAS3,r10
	mtspr	SPRN_MAS7,r16
MMU_FTR_SECTION_ELSE
1096
	mtspr	SPRN_MAS7_MAS3,r10
1097
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157

	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_STATS_X(MMSTAT_TLB_MISS_PT_OK)
	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_STATS_D(MMSTAT_TLB_MISS_PT_FAULT)
	TLB_MISS_EPILOG_ERROR
	b	exc_data_storage_book3e
1:	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_PT_FAULT)
	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
	 */
	ld	r11,PACATOC(r13)
	ld	r11,linear_map_top@got(r11)
	ld	r10,0(r11)
1158 1159
	tovirt(10,10)
	cmpld	cr0,r16,r10
1160 1161 1162 1163 1164 1165 1166 1167
	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 ? */
1168
	PPC_TLBSRX_DOT(0,R16)
1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179
	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
1180 1181 1182 1183 1184 1185

BEGIN_MMU_FTR_SECTION
	srdi	r16,r10,32
	mtspr	SPRN_MAS3,r10
	mtspr	SPRN_MAS7,r16
MMU_FTR_SECTION_ELSE
1186
	mtspr	SPRN_MAS7_MAS3,r10
1187
ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218

	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_STATS_X(MMSTAT_TLB_MISS_LINEAR)
	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


#ifdef CONFIG_BOOK3E_MMU_TLB_STATS
.tlb_stat_inc:
1:	ldarx	r8,0,r9
	addi	r8,r8,1
	stdcx.	r8,0,r9
	bne-	1b
	blr
#endif