1/*
2 *  Low level TLB miss handlers for Book3E
3 *
4 *  Copyright (C) 2008-2009
5 *      Ben. Herrenschmidt (benh@kernel.crashing.org), IBM Corp.
6 *
7 *  This program is free software; you can redistribute it and/or
8 *  modify it under the terms of the GNU General Public License
9 *  as published by the Free Software Foundation; either version
10 *  2 of the License, or (at your option) any later version.
11 */
12
13#include <asm/processor.h>
14#include <asm/reg.h>
15#include <asm/page.h>
16#include <asm/mmu.h>
17#include <asm/ppc_asm.h>
18#include <asm/asm-offsets.h>
19#include <asm/cputable.h>
20#include <asm/pgtable.h>
21#include <asm/exception-64e.h>
22#include <asm/ppc-opcode.h>
23#include <asm/kvm_asm.h>
24#include <asm/kvm_booke_hv_asm.h>
25
26#ifdef CONFIG_PPC_64K_PAGES
27#define VPTE_PMD_SHIFT	(PTE_INDEX_SIZE+1)
28#else
29#define VPTE_PMD_SHIFT	(PTE_INDEX_SIZE)
30#endif
31#define VPTE_PUD_SHIFT	(VPTE_PMD_SHIFT + PMD_INDEX_SIZE)
32#define VPTE_PGD_SHIFT	(VPTE_PUD_SHIFT + PUD_INDEX_SIZE)
33#define VPTE_INDEX_SIZE (VPTE_PGD_SHIFT + PGD_INDEX_SIZE)
34
35/**********************************************************************
36 *                                                                    *
37 * TLB miss handling for Book3E with a bolted linear mapping          *
38 * No virtual page table, no nested TLB misses                        *
39 *                                                                    *
40 **********************************************************************/
41
42/*
43 * Note that, unlike non-bolted handlers, TLB_EXFRAME is not
44 * modified by the TLB miss handlers themselves, since the TLB miss
45 * handler code will not itself cause a recursive TLB miss.
46 *
47 * TLB_EXFRAME will be modified when crit/mc/debug exceptions are
48 * entered/exited.
49 */
50.macro tlb_prolog_bolted intnum addr
51	mtspr	SPRN_SPRG_GEN_SCRATCH,r12
52	mfspr	r12,SPRN_SPRG_TLB_EXFRAME
53	std	r13,EX_TLB_R13(r12)
54	std	r10,EX_TLB_R10(r12)
55	mfspr	r13,SPRN_SPRG_PACA
56
57	mfcr	r10
58	std	r11,EX_TLB_R11(r12)
59#ifdef CONFIG_KVM_BOOKE_HV
60BEGIN_FTR_SECTION
61	mfspr	r11, SPRN_SRR1
62END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
63#endif
64	DO_KVM	\intnum, SPRN_SRR1
65	std	r16,EX_TLB_R16(r12)
66	mfspr	r16,\addr		/* get faulting address */
67	std	r14,EX_TLB_R14(r12)
68	ld	r14,PACAPGD(r13)
69	std	r15,EX_TLB_R15(r12)
70	std	r10,EX_TLB_CR(r12)
71	TLB_MISS_PROLOG_STATS
72.endm
73
74.macro tlb_epilog_bolted
75	ld	r14,EX_TLB_CR(r12)
76	ld	r10,EX_TLB_R10(r12)
77	ld	r11,EX_TLB_R11(r12)
78	ld	r13,EX_TLB_R13(r12)
79	mtcr	r14
80	ld	r14,EX_TLB_R14(r12)
81	ld	r15,EX_TLB_R15(r12)
82	TLB_MISS_RESTORE_STATS
83	ld	r16,EX_TLB_R16(r12)
84	mfspr	r12,SPRN_SPRG_GEN_SCRATCH
85.endm
86
87/* Data TLB miss */
88	START_EXCEPTION(data_tlb_miss_bolted)
89	tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR
90
91	/* We need _PAGE_PRESENT and  _PAGE_ACCESSED set */
92
93	/* We do the user/kernel test for the PID here along with the RW test
94	 */
95	/* We pre-test some combination of permissions to avoid double
96	 * faults:
97	 *
98	 * We move the ESR:ST bit into the position of _PAGE_BAP_SW in the PTE
99	 * ESR_ST   is 0x00800000
100	 * _PAGE_BAP_SW is 0x00000010
101	 * So the shift is >> 19. This tests for supervisor writeability.
102	 * If the page happens to be supervisor writeable and not user
103	 * writeable, we will take a new fault later, but that should be
104	 * a rare enough case.
105	 *
106	 * We also move ESR_ST in _PAGE_DIRTY position
107	 * _PAGE_DIRTY is 0x00001000 so the shift is >> 11
108	 *
109	 * MAS1 is preset for all we need except for TID that needs to
110	 * be cleared for kernel translations
111	 */
112
113	mfspr	r11,SPRN_ESR
114
115	srdi	r15,r16,60		/* get region */
116	rldicl.	r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4
117	bne-	dtlb_miss_fault_bolted	/* Bail if fault addr is invalid */
118
119	rlwinm	r10,r11,32-19,27,27
120	rlwimi	r10,r11,32-16,19,19
121	cmpwi	r15,0			/* user vs kernel check */
122	ori	r10,r10,_PAGE_PRESENT
123	oris	r11,r10,_PAGE_ACCESSED@h
124
125	TLB_MISS_STATS_SAVE_INFO_BOLTED
126	bne	tlb_miss_kernel_bolted
127
128tlb_miss_common_bolted:
129/*
130 * This is the guts of the TLB miss handler for bolted-linear.
131 * We are entered with:
132 *
133 * r16 = faulting address
134 * r15 = crap (free to use)
135 * r14 = page table base
136 * r13 = PACA
137 * r11 = PTE permission mask
138 * r10 = crap (free to use)
139 */
140	rldicl	r15,r16,64-PGDIR_SHIFT+3,64-PGD_INDEX_SIZE-3
141	cmpldi	cr0,r14,0
142	clrrdi	r15,r15,3
143	beq	tlb_miss_fault_bolted	/* No PGDIR, bail */
144
145BEGIN_MMU_FTR_SECTION
146	/* Set the TLB reservation and search for existing entry. Then load
147	 * the entry.
148	 */
149	PPC_TLBSRX_DOT(0,R16)
150	ldx	r14,r14,r15		/* grab pgd entry */
151	beq	tlb_miss_done_bolted	/* tlb exists already, bail */
152MMU_FTR_SECTION_ELSE
153	ldx	r14,r14,r15		/* grab pgd entry */
154ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBRSRV)
155
156#ifndef CONFIG_PPC_64K_PAGES
157	rldicl	r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3
158	clrrdi	r15,r15,3
159	cmpdi	cr0,r14,0
160	bge	tlb_miss_fault_bolted	/* Bad pgd entry or hugepage; bail */
161	ldx	r14,r14,r15		/* grab pud entry */
162#endif /* CONFIG_PPC_64K_PAGES */
163
164	rldicl	r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3
165	clrrdi	r15,r15,3
166	cmpdi	cr0,r14,0
167	bge	tlb_miss_fault_bolted
168	ldx	r14,r14,r15		/* Grab pmd entry */
169
170	rldicl	r15,r16,64-PAGE_SHIFT+3,64-PTE_INDEX_SIZE-3
171	clrrdi	r15,r15,3
172	cmpdi	cr0,r14,0
173	bge	tlb_miss_fault_bolted
174	ldx	r14,r14,r15		/* Grab PTE, normal (!huge) page */
175
176	/* Check if required permissions are met */
177	andc.	r15,r11,r14
178	rldicr	r15,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT
179	bne-	tlb_miss_fault_bolted
180
181	/* Now we build the MAS:
182	 *
183	 * MAS 0   :	Fully setup with defaults in MAS4 and TLBnCFG
184	 * MAS 1   :	Almost fully setup
185	 *               - PID already updated by caller if necessary
186	 *               - TSIZE need change if !base page size, not
187	 *                 yet implemented for now
188	 * MAS 2   :	Defaults not useful, need to be redone
189	 * MAS 3+7 :	Needs to be done
190	 */
191	clrrdi	r11,r16,12		/* Clear low crap in EA */
192	clrldi	r15,r15,12		/* Clear crap at the top */
193	rlwimi	r11,r14,32-19,27,31	/* Insert WIMGE */
194	rlwimi	r15,r14,32-8,22,25	/* Move in U bits */
195	mtspr	SPRN_MAS2,r11
196	andi.	r11,r14,_PAGE_DIRTY
197	rlwimi	r15,r14,32-2,26,31	/* Move in BAP bits */
198
199	/* Mask out SW and UW if !DIRTY (XXX optimize this !) */
200	bne	1f
201	li	r11,MAS3_SW|MAS3_UW
202	andc	r15,r15,r11
2031:
204	mtspr	SPRN_MAS7_MAS3,r15
205	tlbwe
206
207tlb_miss_done_bolted:
208	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_NORM_OK)
209	tlb_epilog_bolted
210	rfi
211
212itlb_miss_kernel_bolted:
213	li	r11,_PAGE_PRESENT|_PAGE_BAP_SX	/* Base perm */
214	oris	r11,r11,_PAGE_ACCESSED@h
215tlb_miss_kernel_bolted:
216	mfspr	r10,SPRN_MAS1
217	ld	r14,PACA_KERNELPGD(r13)
218	cmpldi	cr0,r15,8		/* Check for vmalloc region */
219	rlwinm	r10,r10,0,16,1		/* Clear TID */
220	mtspr	SPRN_MAS1,r10
221	beq+	tlb_miss_common_bolted
222
223tlb_miss_fault_bolted:
224	/* We need to check if it was an instruction miss */
225	andi.	r10,r11,_PAGE_EXEC|_PAGE_BAP_SX
226	bne	itlb_miss_fault_bolted
227dtlb_miss_fault_bolted:
228	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
229	tlb_epilog_bolted
230	b	exc_data_storage_book3e
231itlb_miss_fault_bolted:
232	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT)
233	tlb_epilog_bolted
234	b	exc_instruction_storage_book3e
235
236/* Instruction TLB miss */
237	START_EXCEPTION(instruction_tlb_miss_bolted)
238	tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0
239
240	rldicl.	r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4
241	srdi	r15,r16,60		/* get region */
242	TLB_MISS_STATS_SAVE_INFO_BOLTED
243	bne-	itlb_miss_fault_bolted
244
245	li	r11,_PAGE_PRESENT|_PAGE_EXEC	/* Base perm */
246
247	/* We do the user/kernel test for the PID here along with the RW test
248	 */
249
250	cmpldi	cr0,r15,0			/* Check for user region */
251	oris	r11,r11,_PAGE_ACCESSED@h
252	beq	tlb_miss_common_bolted
253	b	itlb_miss_kernel_bolted
254
255#ifdef CONFIG_PPC_FSL_BOOK3E
256/*
257 * TLB miss handling for e6500 and derivatives, using hardware tablewalk.
258 *
259 * Linear mapping is bolted: no virtual page table or nested TLB misses
260 * Indirect entries in TLB1, hardware loads resulting direct entries
261 *    into TLB0
262 * No HES or NV hint on TLB1, so we need to do software round-robin
263 * No tlbsrx. so we need a spinlock, and we have to deal
264 *    with MAS-damage caused by tlbsx
265 * 4K pages only
266 */
267
268	START_EXCEPTION(instruction_tlb_miss_e6500)
269	tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0
270
271	ld	r11,PACA_TCD_PTR(r13)
272	srdi.	r15,r16,60		/* get region */
273	ori	r16,r16,1
274
275	TLB_MISS_STATS_SAVE_INFO_BOLTED
276	bne	tlb_miss_kernel_e6500	/* user/kernel test */
277
278	b	tlb_miss_common_e6500
279
280	START_EXCEPTION(data_tlb_miss_e6500)
281	tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR
282
283	ld	r11,PACA_TCD_PTR(r13)
284	srdi.	r15,r16,60		/* get region */
285	rldicr	r16,r16,0,62
286
287	TLB_MISS_STATS_SAVE_INFO_BOLTED
288	bne	tlb_miss_kernel_e6500	/* user vs kernel check */
289
290/*
291 * This is the guts of the TLB miss handler for e6500 and derivatives.
292 * We are entered with:
293 *
294 * r16 = page of faulting address (low bit 0 if data, 1 if instruction)
295 * r15 = crap (free to use)
296 * r14 = page table base
297 * r13 = PACA
298 * r11 = tlb_per_core ptr
299 * r10 = crap (free to use)
300 */
301tlb_miss_common_e6500:
302	crmove	cr2*4+2,cr0*4+2		/* cr2.eq != 0 if kernel address */
303
304BEGIN_FTR_SECTION		/* CPU_FTR_SMT */
305	/*
306	 * Search if we already have an indirect entry for that virtual
307	 * address, and if we do, bail out.
308	 *
309	 * MAS6:IND should be already set based on MAS4
310	 */
3111:	lbarx	r15,0,r11
312	lhz	r10,PACAPACAINDEX(r13)
313	cmpdi	r15,0
314	cmpdi	cr1,r15,1	/* set cr1.eq = 0 for non-recursive */
315	addi	r10,r10,1
316	bne	2f
317	stbcx.	r10,0,r11
318	bne	1b
3193:
320	.subsection 1
3212:	cmpd	cr1,r15,r10	/* recursive lock due to mcheck/crit/etc? */
322	beq	cr1,3b		/* unlock will happen if cr1.eq = 0 */
323	lbz	r15,0(r11)
324	cmpdi	r15,0
325	bne	2b
326	b	1b
327	.previous
328
329	/*
330	 * Erratum A-008139 says that we can't use tlbwe to change
331	 * an indirect entry in any way (including replacing or
332	 * invalidating) if the other thread could be in the process
333	 * of a lookup.  The workaround is to invalidate the entry
334	 * with tlbilx before overwriting.
335	 */
336
337	lbz	r15,TCD_ESEL_NEXT(r11)
338	rlwinm	r10,r15,16,0xff0000
339	oris	r10,r10,MAS0_TLBSEL(1)@h
340	mtspr	SPRN_MAS0,r10
341	isync
342	tlbre
343	mfspr	r15,SPRN_MAS1
344	andis.	r15,r15,MAS1_VALID@h
345	beq	5f
346
347BEGIN_FTR_SECTION_NESTED(532)
348	mfspr	r10,SPRN_MAS8
349	rlwinm	r10,r10,0,0x80000fff  /* tgs,tlpid -> sgs,slpid */
350	mtspr	SPRN_MAS5,r10
351END_FTR_SECTION_NESTED(CPU_FTR_EMB_HV,CPU_FTR_EMB_HV,532)
352
353	mfspr	r10,SPRN_MAS1
354	rlwinm	r15,r10,0,0x3fff0000  /* tid -> spid */
355	rlwimi	r15,r10,20,0x00000003 /* ind,ts -> sind,sas */
356	mfspr	r10,SPRN_MAS6
357	mtspr	SPRN_MAS6,r15
358
359	mfspr	r15,SPRN_MAS2
360	isync
361	tlbilxva 0,r15
362	isync
363
364	mtspr	SPRN_MAS6,r10
365
3665:
367BEGIN_FTR_SECTION_NESTED(532)
368	li	r10,0
369	mtspr	SPRN_MAS8,r10
370	mtspr	SPRN_MAS5,r10
371END_FTR_SECTION_NESTED(CPU_FTR_EMB_HV,CPU_FTR_EMB_HV,532)
372
373	tlbsx	0,r16
374	mfspr	r10,SPRN_MAS1
375	andis.	r15,r10,MAS1_VALID@h
376	bne	tlb_miss_done_e6500
377FTR_SECTION_ELSE
378	mfspr	r10,SPRN_MAS1
379ALT_FTR_SECTION_END_IFSET(CPU_FTR_SMT)
380
381	oris	r10,r10,MAS1_VALID@h
382	beq	cr2,4f
383	rlwinm	r10,r10,0,16,1		/* Clear TID */
3844:	mtspr	SPRN_MAS1,r10
385
386	/* Now, we need to walk the page tables. First check if we are in
387	 * range.
388	 */
389	rldicl.	r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4
390	bne-	tlb_miss_fault_e6500
391
392	rldicl	r15,r16,64-PGDIR_SHIFT+3,64-PGD_INDEX_SIZE-3
393	cmpldi	cr0,r14,0
394	clrrdi	r15,r15,3
395	beq-	tlb_miss_fault_e6500 /* No PGDIR, bail */
396	ldx	r14,r14,r15		/* grab pgd entry */
397
398	rldicl	r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3
399	clrrdi	r15,r15,3
400	cmpdi	cr0,r14,0
401	bge	tlb_miss_fault_e6500	/* Bad pgd entry or hugepage; bail */
402	ldx	r14,r14,r15		/* grab pud entry */
403
404	rldicl	r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3
405	clrrdi	r15,r15,3
406	cmpdi	cr0,r14,0
407	bge	tlb_miss_fault_e6500
408	ldx	r14,r14,r15		/* Grab pmd entry */
409
410	mfspr	r10,SPRN_MAS0
411	cmpdi	cr0,r14,0
412	bge	tlb_miss_fault_e6500
413
414	/* Now we build the MAS for a 2M indirect page:
415	 *
416	 * MAS 0   :	ESEL needs to be filled by software round-robin
417	 * MAS 1   :	Fully set up
418	 *               - PID already updated by caller if necessary
419	 *               - TSIZE for now is base ind page size always
420	 *               - TID already cleared if necessary
421	 * MAS 2   :	Default not 2M-aligned, need to be redone
422	 * MAS 3+7 :	Needs to be done
423	 */
424
425	ori	r14,r14,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT)
426	mtspr	SPRN_MAS7_MAS3,r14
427
428	clrrdi	r15,r16,21		/* make EA 2M-aligned */
429	mtspr	SPRN_MAS2,r15
430
431	lbz	r15,TCD_ESEL_NEXT(r11)
432	lbz	r16,TCD_ESEL_MAX(r11)
433	lbz	r14,TCD_ESEL_FIRST(r11)
434	rlwimi	r10,r15,16,0x00ff0000	/* insert esel_next into MAS0 */
435	addi	r15,r15,1		/* increment esel_next */
436	mtspr	SPRN_MAS0,r10
437	cmpw	r15,r16
438	iseleq	r15,r14,r15		/* if next == last use first */
439	stb	r15,TCD_ESEL_NEXT(r11)
440
441	tlbwe
442
443tlb_miss_done_e6500:
444	.macro	tlb_unlock_e6500
445BEGIN_FTR_SECTION
446	beq	cr1,1f		/* no unlock if lock was recursively grabbed */
447	li	r15,0
448	isync
449	stb	r15,0(r11)
4501:
451END_FTR_SECTION_IFSET(CPU_FTR_SMT)
452	.endm
453
454	tlb_unlock_e6500
455	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_NORM_OK)
456	tlb_epilog_bolted
457	rfi
458
459tlb_miss_kernel_e6500:
460	ld	r14,PACA_KERNELPGD(r13)
461	cmpldi	cr1,r15,8		/* Check for vmalloc region */
462	beq+	cr1,tlb_miss_common_e6500
463
464tlb_miss_fault_e6500:
465	tlb_unlock_e6500
466	/* We need to check if it was an instruction miss */
467	andi.	r16,r16,1
468	bne	itlb_miss_fault_e6500
469dtlb_miss_fault_e6500:
470	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
471	tlb_epilog_bolted
472	b	exc_data_storage_book3e
473itlb_miss_fault_e6500:
474	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT)
475	tlb_epilog_bolted
476	b	exc_instruction_storage_book3e
477#endif /* CONFIG_PPC_FSL_BOOK3E */
478
479/**********************************************************************
480 *                                                                    *
481 * TLB miss handling for Book3E with TLB reservation and HES support  *
482 *                                                                    *
483 **********************************************************************/
484
485
486/* Data TLB miss */
487	START_EXCEPTION(data_tlb_miss)
488	TLB_MISS_PROLOG
489
490	/* Now we handle the fault proper. We only save DEAR in normal
491	 * fault case since that's the only interesting values here.
492	 * We could probably also optimize by not saving SRR0/1 in the
493	 * linear mapping case but I'll leave that for later
494	 */
495	mfspr	r14,SPRN_ESR
496	mfspr	r16,SPRN_DEAR		/* get faulting address */
497	srdi	r15,r16,60		/* get region */
498	cmpldi	cr0,r15,0xc		/* linear mapping ? */
499	TLB_MISS_STATS_SAVE_INFO
500	beq	tlb_load_linear		/* yes -> go to linear map load */
501
502	/* The page tables are mapped virtually linear. At this point, though,
503	 * we don't know whether we are trying to fault in a first level
504	 * virtual address or a virtual page table address. We can get that
505	 * from bit 0x1 of the region ID which we have set for a page table
506	 */
507	andi.	r10,r15,0x1
508	bne-	virt_page_table_tlb_miss
509
510	std	r14,EX_TLB_ESR(r12);	/* save ESR */
511	std	r16,EX_TLB_DEAR(r12);	/* save DEAR */
512
513	 /* We need _PAGE_PRESENT and  _PAGE_ACCESSED set */
514	li	r11,_PAGE_PRESENT
515	oris	r11,r11,_PAGE_ACCESSED@h
516
517	/* We do the user/kernel test for the PID here along with the RW test
518	 */
519	cmpldi	cr0,r15,0		/* Check for user region */
520
521	/* We pre-test some combination of permissions to avoid double
522	 * faults:
523	 *
524	 * We move the ESR:ST bit into the position of _PAGE_BAP_SW in the PTE
525	 * ESR_ST   is 0x00800000
526	 * _PAGE_BAP_SW is 0x00000010
527	 * So the shift is >> 19. This tests for supervisor writeability.
528	 * If the page happens to be supervisor writeable and not user
529	 * writeable, we will take a new fault later, but that should be
530	 * a rare enough case.
531	 *
532	 * We also move ESR_ST in _PAGE_DIRTY position
533	 * _PAGE_DIRTY is 0x00001000 so the shift is >> 11
534	 *
535	 * MAS1 is preset for all we need except for TID that needs to
536	 * be cleared for kernel translations
537	 */
538	rlwimi	r11,r14,32-19,27,27
539	rlwimi	r11,r14,32-16,19,19
540	beq	normal_tlb_miss
541	/* XXX replace the RMW cycles with immediate loads + writes */
5421:	mfspr	r10,SPRN_MAS1
543	cmpldi	cr0,r15,8		/* Check for vmalloc region */
544	rlwinm	r10,r10,0,16,1		/* Clear TID */
545	mtspr	SPRN_MAS1,r10
546	beq+	normal_tlb_miss
547
548	/* We got a crappy address, just fault with whatever DEAR and ESR
549	 * are here
550	 */
551	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
552	TLB_MISS_EPILOG_ERROR
553	b	exc_data_storage_book3e
554
555/* Instruction TLB miss */
556	START_EXCEPTION(instruction_tlb_miss)
557	TLB_MISS_PROLOG
558
559	/* If we take a recursive fault, the second level handler may need
560	 * to know whether we are handling a data or instruction fault in
561	 * order to get to the right store fault handler. We provide that
562	 * info by writing a crazy value in ESR in our exception frame
563	 */
564	li	r14,-1	/* store to exception frame is done later */
565
566	/* Now we handle the fault proper. We only save DEAR in the non
567	 * linear mapping case since we know the linear mapping case will
568	 * not re-enter. We could indeed optimize and also not save SRR0/1
569	 * in the linear mapping case but I'll leave that for later
570	 *
571	 * Faulting address is SRR0 which is already in r16
572	 */
573	srdi	r15,r16,60		/* get region */
574	cmpldi	cr0,r15,0xc		/* linear mapping ? */
575	TLB_MISS_STATS_SAVE_INFO
576	beq	tlb_load_linear		/* yes -> go to linear map load */
577
578	/* We do the user/kernel test for the PID here along with the RW test
579	 */
580	li	r11,_PAGE_PRESENT|_PAGE_EXEC	/* Base perm */
581	oris	r11,r11,_PAGE_ACCESSED@h
582
583	cmpldi	cr0,r15,0			/* Check for user region */
584	std	r14,EX_TLB_ESR(r12)		/* write crazy -1 to frame */
585	beq	normal_tlb_miss
586
587	li	r11,_PAGE_PRESENT|_PAGE_BAP_SX	/* Base perm */
588	oris	r11,r11,_PAGE_ACCESSED@h
589	/* XXX replace the RMW cycles with immediate loads + writes */
590	mfspr	r10,SPRN_MAS1
591	cmpldi	cr0,r15,8			/* Check for vmalloc region */
592	rlwinm	r10,r10,0,16,1			/* Clear TID */
593	mtspr	SPRN_MAS1,r10
594	beq+	normal_tlb_miss
595
596	/* We got a crappy address, just fault */
597	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT)
598	TLB_MISS_EPILOG_ERROR
599	b	exc_instruction_storage_book3e
600
601/*
602 * This is the guts of the first-level TLB miss handler for direct
603 * misses. We are entered with:
604 *
605 * r16 = faulting address
606 * r15 = region ID
607 * r14 = crap (free to use)
608 * r13 = PACA
609 * r12 = TLB exception frame in PACA
610 * r11 = PTE permission mask
611 * r10 = crap (free to use)
612 */
613normal_tlb_miss:
614	/* So we first construct the page table address. We do that by
615	 * shifting the bottom of the address (not the region ID) by
616	 * PAGE_SHIFT-3, clearing the bottom 3 bits (get a PTE ptr) and
617	 * or'ing the fourth high bit.
618	 *
619	 * NOTE: For 64K pages, we do things slightly differently in
620	 * order to handle the weird page table format used by linux
621	 */
622	ori	r10,r15,0x1
623#ifdef CONFIG_PPC_64K_PAGES
624	/* For the top bits, 16 bytes per PTE */
625	rldicl	r14,r16,64-(PAGE_SHIFT-4),PAGE_SHIFT-4+4
626	/* Now create the bottom bits as 0 in position 0x8000 and
627	 * the rest calculated for 8 bytes per PTE
628	 */
629	rldicl	r15,r16,64-(PAGE_SHIFT-3),64-15
630	/* Insert the bottom bits in */
631	rlwimi	r14,r15,0,16,31
632#else
633	rldicl	r14,r16,64-(PAGE_SHIFT-3),PAGE_SHIFT-3+4
634#endif
635	sldi	r15,r10,60
636	clrrdi	r14,r14,3
637	or	r10,r15,r14
638
639BEGIN_MMU_FTR_SECTION
640	/* Set the TLB reservation and search for existing entry. Then load
641	 * the entry.
642	 */
643	PPC_TLBSRX_DOT(0,R16)
644	ld	r14,0(r10)
645	beq	normal_tlb_miss_done
646MMU_FTR_SECTION_ELSE
647	ld	r14,0(r10)
648ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBRSRV)
649
650finish_normal_tlb_miss:
651	/* Check if required permissions are met */
652	andc.	r15,r11,r14
653	bne-	normal_tlb_miss_access_fault
654
655	/* Now we build the MAS:
656	 *
657	 * MAS 0   :	Fully setup with defaults in MAS4 and TLBnCFG
658	 * MAS 1   :	Almost fully setup
659	 *               - PID already updated by caller if necessary
660	 *               - TSIZE need change if !base page size, not
661	 *                 yet implemented for now
662	 * MAS 2   :	Defaults not useful, need to be redone
663	 * MAS 3+7 :	Needs to be done
664	 *
665	 * TODO: mix up code below for better scheduling
666	 */
667	clrrdi	r11,r16,12		/* Clear low crap in EA */
668	rlwimi	r11,r14,32-19,27,31	/* Insert WIMGE */
669	mtspr	SPRN_MAS2,r11
670
671	/* Check page size, if not standard, update MAS1 */
672	rldicl	r11,r14,64-8,64-8
673#ifdef CONFIG_PPC_64K_PAGES
674	cmpldi	cr0,r11,BOOK3E_PAGESZ_64K
675#else
676	cmpldi	cr0,r11,BOOK3E_PAGESZ_4K
677#endif
678	beq-	1f
679	mfspr	r11,SPRN_MAS1
680	rlwimi	r11,r14,31,21,24
681	rlwinm	r11,r11,0,21,19
682	mtspr	SPRN_MAS1,r11
6831:
684	/* Move RPN in position */
685	rldicr	r11,r14,64-(PTE_RPN_SHIFT-PAGE_SHIFT),63-PAGE_SHIFT
686	clrldi	r15,r11,12		/* Clear crap at the top */
687	rlwimi	r15,r14,32-8,22,25	/* Move in U bits */
688	rlwimi	r15,r14,32-2,26,31	/* Move in BAP bits */
689
690	/* Mask out SW and UW if !DIRTY (XXX optimize this !) */
691	andi.	r11,r14,_PAGE_DIRTY
692	bne	1f
693	li	r11,MAS3_SW|MAS3_UW
694	andc	r15,r15,r11
6951:
696BEGIN_MMU_FTR_SECTION
697	srdi	r16,r15,32
698	mtspr	SPRN_MAS3,r15
699	mtspr	SPRN_MAS7,r16
700MMU_FTR_SECTION_ELSE
701	mtspr	SPRN_MAS7_MAS3,r15
702ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
703
704	tlbwe
705
706normal_tlb_miss_done:
707	/* We don't bother with restoring DEAR or ESR since we know we are
708	 * level 0 and just going back to userland. They are only needed
709	 * if you are going to take an access fault
710	 */
711	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_NORM_OK)
712	TLB_MISS_EPILOG_SUCCESS
713	rfi
714
715normal_tlb_miss_access_fault:
716	/* We need to check if it was an instruction miss */
717	andi.	r10,r11,_PAGE_EXEC
718	bne	1f
719	ld	r14,EX_TLB_DEAR(r12)
720	ld	r15,EX_TLB_ESR(r12)
721	mtspr	SPRN_DEAR,r14
722	mtspr	SPRN_ESR,r15
723	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
724	TLB_MISS_EPILOG_ERROR
725	b	exc_data_storage_book3e
7261:	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT)
727	TLB_MISS_EPILOG_ERROR
728	b	exc_instruction_storage_book3e
729
730
731/*
732 * This is the guts of the second-level TLB miss handler for direct
733 * misses. We are entered with:
734 *
735 * r16 = virtual page table faulting address
736 * r15 = region (top 4 bits of address)
737 * r14 = crap (free to use)
738 * r13 = PACA
739 * r12 = TLB exception frame in PACA
740 * r11 = crap (free to use)
741 * r10 = crap (free to use)
742 *
743 * Note that this should only ever be called as a second level handler
744 * with the current scheme when using SW load.
745 * That means we can always get the original fault DEAR at
746 * EX_TLB_DEAR-EX_TLB_SIZE(r12)
747 *
748 * It can be re-entered by the linear mapping miss handler. However, to
749 * avoid too much complication, it will restart the whole fault at level
750 * 0 so we don't care too much about clobbers
751 *
752 * XXX That code was written back when we couldn't clobber r14. We can now,
753 * so we could probably optimize things a bit
754 */
755virt_page_table_tlb_miss:
756	/* Are we hitting a kernel page table ? */
757	andi.	r10,r15,0x8
758
759	/* The cool thing now is that r10 contains 0 for user and 8 for kernel,
760	 * and we happen to have the swapper_pg_dir at offset 8 from the user
761	 * pgdir in the PACA :-).
762	 */
763	add	r11,r10,r13
764
765	/* If kernel, we need to clear MAS1 TID */
766	beq	1f
767	/* XXX replace the RMW cycles with immediate loads + writes */
768	mfspr	r10,SPRN_MAS1
769	rlwinm	r10,r10,0,16,1			/* Clear TID */
770	mtspr	SPRN_MAS1,r10
7711:
772BEGIN_MMU_FTR_SECTION
773	/* Search if we already have a TLB entry for that virtual address, and
774	 * if we do, bail out.
775	 */
776	PPC_TLBSRX_DOT(0,R16)
777	beq	virt_page_table_tlb_miss_done
778END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_TLBRSRV)
779
780	/* Now, we need to walk the page tables. First check if we are in
781	 * range.
782	 */
783	rldicl.	r10,r16,64-(VPTE_INDEX_SIZE+3),VPTE_INDEX_SIZE+3+4
784	bne-	virt_page_table_tlb_miss_fault
785
786	/* Get the PGD pointer */
787	ld	r15,PACAPGD(r11)
788	cmpldi	cr0,r15,0
789	beq-	virt_page_table_tlb_miss_fault
790
791	/* Get to PGD entry */
792	rldicl	r11,r16,64-VPTE_PGD_SHIFT,64-PGD_INDEX_SIZE-3
793	clrrdi	r10,r11,3
794	ldx	r15,r10,r15
795	cmpdi	cr0,r15,0
796	bge	virt_page_table_tlb_miss_fault
797
798#ifndef CONFIG_PPC_64K_PAGES
799	/* Get to PUD entry */
800	rldicl	r11,r16,64-VPTE_PUD_SHIFT,64-PUD_INDEX_SIZE-3
801	clrrdi	r10,r11,3
802	ldx	r15,r10,r15
803	cmpdi	cr0,r15,0
804	bge	virt_page_table_tlb_miss_fault
805#endif /* CONFIG_PPC_64K_PAGES */
806
807	/* Get to PMD entry */
808	rldicl	r11,r16,64-VPTE_PMD_SHIFT,64-PMD_INDEX_SIZE-3
809	clrrdi	r10,r11,3
810	ldx	r15,r10,r15
811	cmpdi	cr0,r15,0
812	bge	virt_page_table_tlb_miss_fault
813
814	/* Ok, we're all right, we can now create a kernel translation for
815	 * a 4K or 64K page from r16 -> r15.
816	 */
817	/* Now we build the MAS:
818	 *
819	 * MAS 0   :	Fully setup with defaults in MAS4 and TLBnCFG
820	 * MAS 1   :	Almost fully setup
821	 *               - PID already updated by caller if necessary
822	 *               - TSIZE for now is base page size always
823	 * MAS 2   :	Use defaults
824	 * MAS 3+7 :	Needs to be done
825	 *
826	 * So we only do MAS 2 and 3 for now...
827	 */
828	clrldi	r11,r15,4		/* remove region ID from RPN */
829	ori	r10,r11,1		/* Or-in SR */
830
831BEGIN_MMU_FTR_SECTION
832	srdi	r16,r10,32
833	mtspr	SPRN_MAS3,r10
834	mtspr	SPRN_MAS7,r16
835MMU_FTR_SECTION_ELSE
836	mtspr	SPRN_MAS7_MAS3,r10
837ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
838
839	tlbwe
840
841BEGIN_MMU_FTR_SECTION
842virt_page_table_tlb_miss_done:
843
844	/* We have overriden MAS2:EPN but currently our primary TLB miss
845	 * handler will always restore it so that should not be an issue,
846	 * if we ever optimize the primary handler to not write MAS2 on
847	 * some cases, we'll have to restore MAS2:EPN here based on the
848	 * original fault's DEAR. If we do that we have to modify the
849	 * ITLB miss handler to also store SRR0 in the exception frame
850	 * as DEAR.
851	 *
852	 * However, one nasty thing we did is we cleared the reservation
853	 * (well, potentially we did). We do a trick here thus if we
854	 * are not a level 0 exception (we interrupted the TLB miss) we
855	 * offset the return address by -4 in order to replay the tlbsrx
856	 * instruction there
857	 */
858	subf	r10,r13,r12
859	cmpldi	cr0,r10,PACA_EXTLB+EX_TLB_SIZE
860	bne-	1f
861	ld	r11,PACA_EXTLB+EX_TLB_SIZE+EX_TLB_SRR0(r13)
862	addi	r10,r11,-4
863	std	r10,PACA_EXTLB+EX_TLB_SIZE+EX_TLB_SRR0(r13)
8641:
865END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_TLBRSRV)
866	/* Return to caller, normal case */
867	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_PT_OK);
868	TLB_MISS_EPILOG_SUCCESS
869	rfi
870
871virt_page_table_tlb_miss_fault:
872	/* If we fault here, things are a little bit tricky. We need to call
873	 * either data or instruction store fault, and we need to retrieve
874	 * the original fault address and ESR (for data).
875	 *
876	 * The thing is, we know that in normal circumstances, this is
877	 * always called as a second level tlb miss for SW load or as a first
878	 * 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	 * However, we do need to double check that, because we may just hit
882	 * a stray kernel pointer or a userland attack trying to hit those
883	 * areas. If that is the case, we do a data fault. (We can't get here
884	 * from an instruction tlb miss anyway).
885	 *
886	 * Note also that when going to a fault, we must unwind the previous
887	 * level as well. Since we are doing that, we don't need to clear or
888	 * restore the TLB reservation neither.
889	 */
890	subf	r10,r13,r12
891	cmpldi	cr0,r10,PACA_EXTLB+EX_TLB_SIZE
892	bne-	virt_page_table_tlb_miss_whacko_fault
893
894	/* We dig the original DEAR and ESR from slot 0 */
895	ld	r15,EX_TLB_DEAR+PACA_EXTLB(r13)
896	ld	r16,EX_TLB_ESR+PACA_EXTLB(r13)
897
898	/* We check for the "special" ESR value for instruction faults */
899	cmpdi	cr0,r16,-1
900	beq	1f
901	mtspr	SPRN_DEAR,r15
902	mtspr	SPRN_ESR,r16
903	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_PT_FAULT);
904	TLB_MISS_EPILOG_ERROR
905	b	exc_data_storage_book3e
9061:	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_PT_FAULT);
907	TLB_MISS_EPILOG_ERROR
908	b	exc_instruction_storage_book3e
909
910virt_page_table_tlb_miss_whacko_fault:
911	/* The linear fault will restart everything so ESR and DEAR will
912	 * not have been clobbered, let's just fault with what we have
913	 */
914	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_PT_FAULT);
915	TLB_MISS_EPILOG_ERROR
916	b	exc_data_storage_book3e
917
918
919/**************************************************************
920 *                                                            *
921 * TLB miss handling for Book3E with hw page table support    *
922 *                                                            *
923 **************************************************************/
924
925
926/* Data TLB miss */
927	START_EXCEPTION(data_tlb_miss_htw)
928	TLB_MISS_PROLOG
929
930	/* Now we handle the fault proper. We only save DEAR in normal
931	 * fault case since that's the only interesting values here.
932	 * We could probably also optimize by not saving SRR0/1 in the
933	 * linear mapping case but I'll leave that for later
934	 */
935	mfspr	r14,SPRN_ESR
936	mfspr	r16,SPRN_DEAR		/* get faulting address */
937	srdi	r11,r16,60		/* get region */
938	cmpldi	cr0,r11,0xc		/* linear mapping ? */
939	TLB_MISS_STATS_SAVE_INFO
940	beq	tlb_load_linear		/* yes -> go to linear map load */
941
942	/* We do the user/kernel test for the PID here along with the RW test
943	 */
944	cmpldi	cr0,r11,0		/* Check for user region */
945	ld	r15,PACAPGD(r13)	/* Load user pgdir */
946	beq	htw_tlb_miss
947
948	/* XXX replace the RMW cycles with immediate loads + writes */
9491:	mfspr	r10,SPRN_MAS1
950	cmpldi	cr0,r11,8		/* Check for vmalloc region */
951	rlwinm	r10,r10,0,16,1		/* Clear TID */
952	mtspr	SPRN_MAS1,r10
953	ld	r15,PACA_KERNELPGD(r13)	/* Load kernel pgdir */
954	beq+	htw_tlb_miss
955
956	/* We got a crappy address, just fault with whatever DEAR and ESR
957	 * are here
958	 */
959	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT)
960	TLB_MISS_EPILOG_ERROR
961	b	exc_data_storage_book3e
962
963/* Instruction TLB miss */
964	START_EXCEPTION(instruction_tlb_miss_htw)
965	TLB_MISS_PROLOG
966
967	/* If we take a recursive fault, the second level handler may need
968	 * to know whether we are handling a data or instruction fault in
969	 * order to get to the right store fault handler. We provide that
970	 * info by keeping a crazy value for ESR in r14
971	 */
972	li	r14,-1	/* store to exception frame is done later */
973
974	/* Now we handle the fault proper. We only save DEAR in the non
975	 * linear mapping case since we know the linear mapping case will
976	 * not re-enter. We could indeed optimize and also not save SRR0/1
977	 * in the linear mapping case but I'll leave that for later
978	 *
979	 * Faulting address is SRR0 which is already in r16
980	 */
981	srdi	r11,r16,60		/* get region */
982	cmpldi	cr0,r11,0xc		/* linear mapping ? */
983	TLB_MISS_STATS_SAVE_INFO
984	beq	tlb_load_linear		/* yes -> go to linear map load */
985
986	/* We do the user/kernel test for the PID here along with the RW test
987	 */
988	cmpldi	cr0,r11,0			/* Check for user region */
989	ld	r15,PACAPGD(r13)		/* Load user pgdir */
990	beq	htw_tlb_miss
991
992	/* XXX replace the RMW cycles with immediate loads + writes */
9931:	mfspr	r10,SPRN_MAS1
994	cmpldi	cr0,r11,8			/* Check for vmalloc region */
995	rlwinm	r10,r10,0,16,1			/* Clear TID */
996	mtspr	SPRN_MAS1,r10
997	ld	r15,PACA_KERNELPGD(r13)		/* Load kernel pgdir */
998	beq+	htw_tlb_miss
999
1000	/* We got a crappy address, just fault */
1001	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT)
1002	TLB_MISS_EPILOG_ERROR
1003	b	exc_instruction_storage_book3e
1004
1005
1006/*
1007 * This is the guts of the second-level TLB miss handler for direct
1008 * misses. We are entered with:
1009 *
1010 * r16 = virtual page table faulting address
1011 * r15 = PGD pointer
1012 * r14 = ESR
1013 * r13 = PACA
1014 * r12 = TLB exception frame in PACA
1015 * r11 = crap (free to use)
1016 * r10 = crap (free to use)
1017 *
1018 * It can be re-entered by the linear mapping miss handler. However, to
1019 * avoid too much complication, it will save/restore things for us
1020 */
1021htw_tlb_miss:
1022	/* Search if we already have a TLB entry for that virtual address, and
1023	 * if we do, bail out.
1024	 *
1025	 * MAS1:IND should be already set based on MAS4
1026	 */
1027	PPC_TLBSRX_DOT(0,R16)
1028	beq	htw_tlb_miss_done
1029
1030	/* Now, we need to walk the page tables. First check if we are in
1031	 * range.
1032	 */
1033	rldicl.	r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4
1034	bne-	htw_tlb_miss_fault
1035
1036	/* Get the PGD pointer */
1037	cmpldi	cr0,r15,0
1038	beq-	htw_tlb_miss_fault
1039
1040	/* Get to PGD entry */
1041	rldicl	r11,r16,64-(PGDIR_SHIFT-3),64-PGD_INDEX_SIZE-3
1042	clrrdi	r10,r11,3
1043	ldx	r15,r10,r15
1044	cmpdi	cr0,r15,0
1045	bge	htw_tlb_miss_fault
1046
1047#ifndef CONFIG_PPC_64K_PAGES
1048	/* Get to PUD entry */
1049	rldicl	r11,r16,64-(PUD_SHIFT-3),64-PUD_INDEX_SIZE-3
1050	clrrdi	r10,r11,3
1051	ldx	r15,r10,r15
1052	cmpdi	cr0,r15,0
1053	bge	htw_tlb_miss_fault
1054#endif /* CONFIG_PPC_64K_PAGES */
1055
1056	/* Get to PMD entry */
1057	rldicl	r11,r16,64-(PMD_SHIFT-3),64-PMD_INDEX_SIZE-3
1058	clrrdi	r10,r11,3
1059	ldx	r15,r10,r15
1060	cmpdi	cr0,r15,0
1061	bge	htw_tlb_miss_fault
1062
1063	/* Ok, we're all right, we can now create an indirect entry for
1064	 * a 1M or 256M page.
1065	 *
1066	 * The last trick is now that because we use "half" pages for
1067	 * the HTW (1M IND is 2K and 256M IND is 32K) we need to account
1068	 * for an added LSB bit to the RPN. For 64K pages, there is no
1069	 * problem as we already use 32K arrays (half PTE pages), but for
1070	 * 4K page we need to extract a bit from the virtual address and
1071	 * insert it into the "PA52" bit of the RPN.
1072	 */
1073#ifndef CONFIG_PPC_64K_PAGES
1074	rlwimi	r15,r16,32-9,20,20
1075#endif
1076	/* Now we build the MAS:
1077	 *
1078	 * MAS 0   :	Fully setup with defaults in MAS4 and TLBnCFG
1079	 * MAS 1   :	Almost fully setup
1080	 *               - PID already updated by caller if necessary
1081	 *               - TSIZE for now is base ind page size always
1082	 * MAS 2   :	Use defaults
1083	 * MAS 3+7 :	Needs to be done
1084	 */
1085#ifdef CONFIG_PPC_64K_PAGES
1086	ori	r10,r15,(BOOK3E_PAGESZ_64K << MAS3_SPSIZE_SHIFT)
1087#else
1088	ori	r10,r15,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT)
1089#endif
1090
1091BEGIN_MMU_FTR_SECTION
1092	srdi	r16,r10,32
1093	mtspr	SPRN_MAS3,r10
1094	mtspr	SPRN_MAS7,r16
1095MMU_FTR_SECTION_ELSE
1096	mtspr	SPRN_MAS7_MAS3,r10
1097ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
1098
1099	tlbwe
1100
1101htw_tlb_miss_done:
1102	/* We don't bother with restoring DEAR or ESR since we know we are
1103	 * level 0 and just going back to userland. They are only needed
1104	 * if you are going to take an access fault
1105	 */
1106	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_PT_OK)
1107	TLB_MISS_EPILOG_SUCCESS
1108	rfi
1109
1110htw_tlb_miss_fault:
1111	/* We need to check if it was an instruction miss. We know this
1112	 * though because r14 would contain -1
1113	 */
1114	cmpdi	cr0,r14,-1
1115	beq	1f
1116	mtspr	SPRN_DEAR,r16
1117	mtspr	SPRN_ESR,r14
1118	TLB_MISS_STATS_D(MMSTAT_TLB_MISS_PT_FAULT)
1119	TLB_MISS_EPILOG_ERROR
1120	b	exc_data_storage_book3e
11211:	TLB_MISS_STATS_I(MMSTAT_TLB_MISS_PT_FAULT)
1122	TLB_MISS_EPILOG_ERROR
1123	b	exc_instruction_storage_book3e
1124
1125/*
1126 * This is the guts of "any" level TLB miss handler for kernel linear
1127 * mapping misses. We are entered with:
1128 *
1129 *
1130 * r16 = faulting address
1131 * r15 = crap (free to use)
1132 * r14 = ESR (data) or -1 (instruction)
1133 * r13 = PACA
1134 * r12 = TLB exception frame in PACA
1135 * r11 = crap (free to use)
1136 * r10 = crap (free to use)
1137 *
1138 * In addition we know that we will not re-enter, so in theory, we could
1139 * use a simpler epilog not restoring SRR0/1 etc.. but we'll do that later.
1140 *
1141 * We also need to be careful about MAS registers here & TLB reservation,
1142 * as we know we'll have clobbered them if we interrupt the main TLB miss
1143 * handlers in which case we probably want to do a full restart at level
1144 * 0 rather than saving / restoring the MAS.
1145 *
1146 * Note: If we care about performance of that core, we can easily shuffle
1147 *       a few things around
1148 */
1149tlb_load_linear:
1150	/* For now, we assume the linear mapping is contiguous and stops at
1151	 * linear_map_top. We also assume the size is a multiple of 1G, thus
1152	 * we only use 1G pages for now. That might have to be changed in a
1153	 * final implementation, especially when dealing with hypervisors
1154	 */
1155	ld	r11,PACATOC(r13)
1156	ld	r11,linear_map_top@got(r11)
1157	ld	r10,0(r11)
1158	tovirt(10,10)
1159	cmpld	cr0,r16,r10
1160	bge	tlb_load_linear_fault
1161
1162	/* MAS1 need whole new setup. */
1163	li	r15,(BOOK3E_PAGESZ_1GB<<MAS1_TSIZE_SHIFT)
1164	oris	r15,r15,MAS1_VALID@h	/* MAS1 needs V and TSIZE */
1165	mtspr	SPRN_MAS1,r15
1166
1167	/* Already somebody there ? */
1168	PPC_TLBSRX_DOT(0,R16)
1169	beq	tlb_load_linear_done
1170
1171	/* Now we build the remaining MAS. MAS0 and 2 should be fine
1172	 * with their defaults, which leaves us with MAS 3 and 7. The
1173	 * mapping is linear, so we just take the address, clear the
1174	 * region bits, and or in the permission bits which are currently
1175	 * hard wired
1176	 */
1177	clrrdi	r10,r16,30		/* 1G page index */
1178	clrldi	r10,r10,4		/* clear region bits */
1179	ori	r10,r10,MAS3_SR|MAS3_SW|MAS3_SX
1180
1181BEGIN_MMU_FTR_SECTION
1182	srdi	r16,r10,32
1183	mtspr	SPRN_MAS3,r10
1184	mtspr	SPRN_MAS7,r16
1185MMU_FTR_SECTION_ELSE
1186	mtspr	SPRN_MAS7_MAS3,r10
1187ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_USE_PAIRED_MAS)
1188
1189	tlbwe
1190
1191tlb_load_linear_done:
1192	/* We use the "error" epilog for success as we do want to
1193	 * restore to the initial faulting context, whatever it was.
1194	 * We do that because we can't resume a fault within a TLB
1195	 * miss handler, due to MAS and TLB reservation being clobbered.
1196	 */
1197	TLB_MISS_STATS_X(MMSTAT_TLB_MISS_LINEAR)
1198	TLB_MISS_EPILOG_ERROR
1199	rfi
1200
1201tlb_load_linear_fault:
1202	/* We keep the DEAR and ESR around, this shouldn't have happened */
1203	cmpdi	cr0,r14,-1
1204	beq	1f
1205	TLB_MISS_EPILOG_ERROR_SPECIAL
1206	b	exc_data_storage_book3e
12071:	TLB_MISS_EPILOG_ERROR_SPECIAL
1208	b	exc_instruction_storage_book3e
1209
1210
1211#ifdef CONFIG_BOOK3E_MMU_TLB_STATS
1212.tlb_stat_inc:
12131:	ldarx	r8,0,r9
1214	addi	r8,r8,1
1215	stdcx.	r8,0,r9
1216	bne-	1b
1217	blr
1218#endif
1219