Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (134 commits)
  powerpc/nvram: Enable use Generic NVRAM driver for different size chips
  powerpc/iseries: Fix oops reading from /proc/iSeries/mf/*/cmdline
  powerpc/ps3: Workaround for flash memory I/O error
  powerpc/booke: Don't set DABR on 64-bit BookE, use DAC1 instead
  powerpc/perf_counters: Reduce stack usage of power_check_constraints
  powerpc: Fix bug where perf_counters breaks oprofile
  powerpc/85xx: Fix SMP compile error and allow NULL for smp_ops
  powerpc/irq: Improve nanodoc
  powerpc: Fix some late PowerMac G5 with PCIe ATI graphics
  powerpc/fsl-booke: Use HW PTE format if CONFIG_PTE_64BIT
  powerpc/book3e: Add missing page sizes
  powerpc/pseries: Fix to handle slb resize across migration
  powerpc/powermac: Thermal control turns system off too eagerly
  powerpc/pci: Merge ppc32 and ppc64 versions of phb_scan()
  powerpc/405ex: support cuImage via included dtb
  powerpc/405ex: provide necessary fixup function to support cuImage
  powerpc/40x: Add support for the ESTeem 195E (PPC405EP) SBC
  powerpc/44x: Add Eiger AMCC (AppliedMicro) PPC460SX evaluation board support.
  powerpc/44x: Update Arches defconfig
  powerpc/44x: Update Arches dts
  ...

Fix up conflicts in drivers/char/agp/uninorth-agp.c

1 files changed, 770 insertions, 0 deletions

diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S
new file mode 100644
index 00000000000..ef1cccf7117
--- /dev/null
+++ b/arch/powerpc/mm/tlb_low_64e.S
@@ -0,0 +1,770 @@
+/*
+ *  Low leve TLB miss handlers for Book3E
+ *
+ *  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/reg.h>
+#include <asm/exception-64e.h>
+#include <asm/ppc-opcode.h>
+
+#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)
+
+
+/**********************************************************************
+ *                                                                    *
+ * 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
+	 */
+	li	r11,_PAGE_PRESENT|_PAGE_EXEC	/* Base perm */
+	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
+	/* 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 */
+	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
+
+BEGIN_MMU_FTR_SECTION
+	/* Set the TLB reservation and seach for existing entry. Then load
+	 * the entry.
+	 */
+	PPC_TLBSRX_DOT(0,r16)
+	ld	r14,0(r10)
+	beq	normal_tlb_miss_done
+MMU_FTR_SECTION_ELSE
+	ld	r14,0(r10)
+ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBRSRV)
+
+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
+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)
+
+	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 */
+	andi.	r10,r11,_PAGE_EXEC
+	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:
+BEGIN_MMU_FTR_SECTION
+	/* Search if we already have a TLB entry for that virtual address, and
+	 * if we do, bail out.
+	 */
+	PPC_TLBSRX_DOT(0,r16)
+	beq	virt_page_table_tlb_miss_done
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_TLBRSRV)
+
+	/* 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
+	cmpldi	cr0,r15,0
+	beq	virt_page_table_tlb_miss_fault
+
+#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
+	cmpldi	cr0,r15,0
+	beq	virt_page_table_tlb_miss_fault
+#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
+	cmpldi	cr0,r15,0
+	beq	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 */
+
+BEGIN_MMU_FTR_SECTION
+	srdi	r16,r10,32
+	mtspr	SPRN_MAS3,r10
+	mtspr	SPRN_MAS7,r16
+MMU_FTR_SECTION_ELSE
+	mtspr	SPRN_MAS7_MAS3,r10
+ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
+
+	tlbwe
+
+BEGIN_MMU_FTR_SECTION
+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:
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_TLBRSRV)
+	/* 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
+	 * either data or instruction store fault, and we need to retreive
+	 * 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 informations 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_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
+	 */
+	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
+	cmpldi	cr0,r15,0
+	beq	htw_tlb_miss_fault
+
+#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
+	cmpldi	cr0,r15,0
+	beq	htw_tlb_miss_fault
+#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
+	cmpldi	cr0,r15,0
+	beq	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.
+	 */
+#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
+
+BEGIN_MMU_FTR_SECTION
+	srdi	r16,r10,32
+	mtspr	SPRN_MAS3,r10
+	mtspr	SPRN_MAS7,r16
+MMU_FTR_SECTION_ELSE
+	mtspr	SPRN_MAS7_MAS3,r10
+ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
+
+	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)
+	cmpld	cr0,r10,r16
+	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
+
+BEGIN_MMU_FTR_SECTION
+	srdi	r16,r10,32
+	mtspr	SPRN_MAS3,r10
+	mtspr	SPRN_MAS7,r16
+MMU_FTR_SECTION_ELSE
+	mtspr	SPRN_MAS7_MAS3,r10
+ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
+
+	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