1/*
2 * This file contains the routines for TLB flushing.
3 * On machines where the MMU does not use a hash table to store virtual to
4 * physical translations (ie, SW loaded TLBs or Book3E compilant processors,
5 * this does -not- include 603 however which shares the implementation with
6 * hash based processors)
7 *
8 *  -- BenH
9 *
10 * Copyright 2008,2009 Ben Herrenschmidt <benh@kernel.crashing.org>
11 *                     IBM Corp.
12 *
13 *  Derived from arch/ppc/mm/init.c:
14 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
15 *
16 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
17 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
18 *    Copyright (C) 1996 Paul Mackerras
19 *
20 *  Derived from "arch/i386/mm/init.c"
21 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
22 *
23 *  This program is free software; you can redistribute it and/or
24 *  modify it under the terms of the GNU General Public License
25 *  as published by the Free Software Foundation; either version
26 *  2 of the License, or (at your option) any later version.
27 *
28 */
29
30#include <linux/kernel.h>
31#include <linux/export.h>
32#include <linux/mm.h>
33#include <linux/init.h>
34#include <linux/highmem.h>
35#include <linux/pagemap.h>
36#include <linux/preempt.h>
37#include <linux/spinlock.h>
38#include <linux/memblock.h>
39#include <linux/of_fdt.h>
40#include <linux/hugetlb.h>
41
42#include <asm/tlbflush.h>
43#include <asm/tlb.h>
44#include <asm/code-patching.h>
45#include <asm/hugetlb.h>
46#include <asm/paca.h>
47
48#include "mmu_decl.h"
49
50/*
51 * This struct lists the sw-supported page sizes.  The hardawre MMU may support
52 * other sizes not listed here.   The .ind field is only used on MMUs that have
53 * indirect page table entries.
54 */
55#ifdef CONFIG_PPC_BOOK3E_MMU
56#ifdef CONFIG_PPC_FSL_BOOK3E
57struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
58	[MMU_PAGE_4K] = {
59		.shift	= 12,
60		.enc	= BOOK3E_PAGESZ_4K,
61	},
62	[MMU_PAGE_2M] = {
63		.shift	= 21,
64		.enc	= BOOK3E_PAGESZ_2M,
65	},
66	[MMU_PAGE_4M] = {
67		.shift	= 22,
68		.enc	= BOOK3E_PAGESZ_4M,
69	},
70	[MMU_PAGE_16M] = {
71		.shift	= 24,
72		.enc	= BOOK3E_PAGESZ_16M,
73	},
74	[MMU_PAGE_64M] = {
75		.shift	= 26,
76		.enc	= BOOK3E_PAGESZ_64M,
77	},
78	[MMU_PAGE_256M] = {
79		.shift	= 28,
80		.enc	= BOOK3E_PAGESZ_256M,
81	},
82	[MMU_PAGE_1G] = {
83		.shift	= 30,
84		.enc	= BOOK3E_PAGESZ_1GB,
85	},
86};
87#else
88struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
89	[MMU_PAGE_4K] = {
90		.shift	= 12,
91		.ind	= 20,
92		.enc	= BOOK3E_PAGESZ_4K,
93	},
94	[MMU_PAGE_16K] = {
95		.shift	= 14,
96		.enc	= BOOK3E_PAGESZ_16K,
97	},
98	[MMU_PAGE_64K] = {
99		.shift	= 16,
100		.ind	= 28,
101		.enc	= BOOK3E_PAGESZ_64K,
102	},
103	[MMU_PAGE_1M] = {
104		.shift	= 20,
105		.enc	= BOOK3E_PAGESZ_1M,
106	},
107	[MMU_PAGE_16M] = {
108		.shift	= 24,
109		.ind	= 36,
110		.enc	= BOOK3E_PAGESZ_16M,
111	},
112	[MMU_PAGE_256M] = {
113		.shift	= 28,
114		.enc	= BOOK3E_PAGESZ_256M,
115	},
116	[MMU_PAGE_1G] = {
117		.shift	= 30,
118		.enc	= BOOK3E_PAGESZ_1GB,
119	},
120};
121#endif /* CONFIG_FSL_BOOKE */
122
123static inline int mmu_get_tsize(int psize)
124{
125	return mmu_psize_defs[psize].enc;
126}
127#else
128static inline int mmu_get_tsize(int psize)
129{
130	/* This isn't used on !Book3E for now */
131	return 0;
132}
133#endif /* CONFIG_PPC_BOOK3E_MMU */
134
135/* The variables below are currently only used on 64-bit Book3E
136 * though this will probably be made common with other nohash
137 * implementations at some point
138 */
139#ifdef CONFIG_PPC64
140
141int mmu_linear_psize;		/* Page size used for the linear mapping */
142int mmu_pte_psize;		/* Page size used for PTE pages */
143int mmu_vmemmap_psize;		/* Page size used for the virtual mem map */
144int book3e_htw_mode;		/* HW tablewalk?  Value is PPC_HTW_* */
145unsigned long linear_map_top;	/* Top of linear mapping */
146
147
148/*
149 * Number of bytes to add to SPRN_SPRG_TLB_EXFRAME on crit/mcheck/debug
150 * exceptions.  This is used for bolted and e6500 TLB miss handlers which
151 * do not modify this SPRG in the TLB miss code; for other TLB miss handlers,
152 * this is set to zero.
153 */
154int extlb_level_exc;
155
156#endif /* CONFIG_PPC64 */
157
158#ifdef CONFIG_PPC_FSL_BOOK3E
159/* next_tlbcam_idx is used to round-robin tlbcam entry assignment */
160DEFINE_PER_CPU(int, next_tlbcam_idx);
161EXPORT_PER_CPU_SYMBOL(next_tlbcam_idx);
162#endif
163
164/*
165 * Base TLB flushing operations:
166 *
167 *  - flush_tlb_mm(mm) flushes the specified mm context TLB's
168 *  - flush_tlb_page(vma, vmaddr) flushes one page
169 *  - flush_tlb_range(vma, start, end) flushes a range of pages
170 *  - flush_tlb_kernel_range(start, end) flushes kernel pages
171 *
172 *  - local_* variants of page and mm only apply to the current
173 *    processor
174 */
175
176/*
177 * These are the base non-SMP variants of page and mm flushing
178 */
179void local_flush_tlb_mm(struct mm_struct *mm)
180{
181	unsigned int pid;
182
183	preempt_disable();
184	pid = mm->context.id;
185	if (pid != MMU_NO_CONTEXT)
186		_tlbil_pid(pid);
187	preempt_enable();
188}
189EXPORT_SYMBOL(local_flush_tlb_mm);
190
191void __local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
192			    int tsize, int ind)
193{
194	unsigned int pid;
195
196	preempt_disable();
197	pid = mm ? mm->context.id : 0;
198	if (pid != MMU_NO_CONTEXT)
199		_tlbil_va(vmaddr, pid, tsize, ind);
200	preempt_enable();
201}
202
203void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
204{
205	__local_flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
206			       mmu_get_tsize(mmu_virtual_psize), 0);
207}
208EXPORT_SYMBOL(local_flush_tlb_page);
209
210/*
211 * And here are the SMP non-local implementations
212 */
213#ifdef CONFIG_SMP
214
215static DEFINE_RAW_SPINLOCK(tlbivax_lock);
216
217static int mm_is_core_local(struct mm_struct *mm)
218{
219	return cpumask_subset(mm_cpumask(mm),
220			      topology_thread_cpumask(smp_processor_id()));
221}
222
223struct tlb_flush_param {
224	unsigned long addr;
225	unsigned int pid;
226	unsigned int tsize;
227	unsigned int ind;
228};
229
230static void do_flush_tlb_mm_ipi(void *param)
231{
232	struct tlb_flush_param *p = param;
233
234	_tlbil_pid(p ? p->pid : 0);
235}
236
237static void do_flush_tlb_page_ipi(void *param)
238{
239	struct tlb_flush_param *p = param;
240
241	_tlbil_va(p->addr, p->pid, p->tsize, p->ind);
242}
243
244
245/* Note on invalidations and PID:
246 *
247 * We snapshot the PID with preempt disabled. At this point, it can still
248 * change either because:
249 * - our context is being stolen (PID -> NO_CONTEXT) on another CPU
250 * - we are invaliating some target that isn't currently running here
251 *   and is concurrently acquiring a new PID on another CPU
252 * - some other CPU is re-acquiring a lost PID for this mm
253 * etc...
254 *
255 * However, this shouldn't be a problem as we only guarantee
256 * invalidation of TLB entries present prior to this call, so we
257 * don't care about the PID changing, and invalidating a stale PID
258 * is generally harmless.
259 */
260
261void flush_tlb_mm(struct mm_struct *mm)
262{
263	unsigned int pid;
264
265	preempt_disable();
266	pid = mm->context.id;
267	if (unlikely(pid == MMU_NO_CONTEXT))
268		goto no_context;
269	if (!mm_is_core_local(mm)) {
270		struct tlb_flush_param p = { .pid = pid };
271		/* Ignores smp_processor_id() even if set. */
272		smp_call_function_many(mm_cpumask(mm),
273				       do_flush_tlb_mm_ipi, &p, 1);
274	}
275	_tlbil_pid(pid);
276 no_context:
277	preempt_enable();
278}
279EXPORT_SYMBOL(flush_tlb_mm);
280
281void __flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
282		      int tsize, int ind)
283{
284	struct cpumask *cpu_mask;
285	unsigned int pid;
286
287	/*
288	 * This function as well as __local_flush_tlb_page() must only be called
289	 * for user contexts.
290	 */
291	if (unlikely(WARN_ON(!mm)))
292		return;
293
294	preempt_disable();
295	pid = mm->context.id;
296	if (unlikely(pid == MMU_NO_CONTEXT))
297		goto bail;
298	cpu_mask = mm_cpumask(mm);
299	if (!mm_is_core_local(mm)) {
300		/* If broadcast tlbivax is supported, use it */
301		if (mmu_has_feature(MMU_FTR_USE_TLBIVAX_BCAST)) {
302			int lock = mmu_has_feature(MMU_FTR_LOCK_BCAST_INVAL);
303			if (lock)
304				raw_spin_lock(&tlbivax_lock);
305			_tlbivax_bcast(vmaddr, pid, tsize, ind);
306			if (lock)
307				raw_spin_unlock(&tlbivax_lock);
308			goto bail;
309		} else {
310			struct tlb_flush_param p = {
311				.pid = pid,
312				.addr = vmaddr,
313				.tsize = tsize,
314				.ind = ind,
315			};
316			/* Ignores smp_processor_id() even if set in cpu_mask */
317			smp_call_function_many(cpu_mask,
318					       do_flush_tlb_page_ipi, &p, 1);
319		}
320	}
321	_tlbil_va(vmaddr, pid, tsize, ind);
322 bail:
323	preempt_enable();
324}
325
326void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
327{
328#ifdef CONFIG_HUGETLB_PAGE
329	if (vma && is_vm_hugetlb_page(vma))
330		flush_hugetlb_page(vma, vmaddr);
331#endif
332
333	__flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
334			 mmu_get_tsize(mmu_virtual_psize), 0);
335}
336EXPORT_SYMBOL(flush_tlb_page);
337
338#endif /* CONFIG_SMP */
339
340#ifdef CONFIG_PPC_47x
341void __init early_init_mmu_47x(void)
342{
343#ifdef CONFIG_SMP
344	unsigned long root = of_get_flat_dt_root();
345	if (of_get_flat_dt_prop(root, "cooperative-partition", NULL))
346		mmu_clear_feature(MMU_FTR_USE_TLBIVAX_BCAST);
347#endif /* CONFIG_SMP */
348}
349#endif /* CONFIG_PPC_47x */
350
351/*
352 * Flush kernel TLB entries in the given range
353 */
354void flush_tlb_kernel_range(unsigned long start, unsigned long end)
355{
356#ifdef CONFIG_SMP
357	preempt_disable();
358	smp_call_function(do_flush_tlb_mm_ipi, NULL, 1);
359	_tlbil_pid(0);
360	preempt_enable();
361#else
362	_tlbil_pid(0);
363#endif
364}
365EXPORT_SYMBOL(flush_tlb_kernel_range);
366
367/*
368 * Currently, for range flushing, we just do a full mm flush. This should
369 * be optimized based on a threshold on the size of the range, since
370 * some implementation can stack multiple tlbivax before a tlbsync but
371 * for now, we keep it that way
372 */
373void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
374		     unsigned long end)
375
376{
377	flush_tlb_mm(vma->vm_mm);
378}
379EXPORT_SYMBOL(flush_tlb_range);
380
381void tlb_flush(struct mmu_gather *tlb)
382{
383	flush_tlb_mm(tlb->mm);
384}
385
386/*
387 * Below are functions specific to the 64-bit variant of Book3E though that
388 * may change in the future
389 */
390
391#ifdef CONFIG_PPC64
392
393/*
394 * Handling of virtual linear page tables or indirect TLB entries
395 * flushing when PTE pages are freed
396 */
397void tlb_flush_pgtable(struct mmu_gather *tlb, unsigned long address)
398{
399	int tsize = mmu_psize_defs[mmu_pte_psize].enc;
400
401	if (book3e_htw_mode != PPC_HTW_NONE) {
402		unsigned long start = address & PMD_MASK;
403		unsigned long end = address + PMD_SIZE;
404		unsigned long size = 1UL << mmu_psize_defs[mmu_pte_psize].shift;
405
406		/* This isn't the most optimal, ideally we would factor out the
407		 * while preempt & CPU mask mucking around, or even the IPI but
408		 * it will do for now
409		 */
410		while (start < end) {
411			__flush_tlb_page(tlb->mm, start, tsize, 1);
412			start += size;
413		}
414	} else {
415		unsigned long rmask = 0xf000000000000000ul;
416		unsigned long rid = (address & rmask) | 0x1000000000000000ul;
417		unsigned long vpte = address & ~rmask;
418
419#ifdef CONFIG_PPC_64K_PAGES
420		vpte = (vpte >> (PAGE_SHIFT - 4)) & ~0xfffful;
421#else
422		vpte = (vpte >> (PAGE_SHIFT - 3)) & ~0xffful;
423#endif
424		vpte |= rid;
425		__flush_tlb_page(tlb->mm, vpte, tsize, 0);
426	}
427}
428
429static void setup_page_sizes(void)
430{
431	unsigned int tlb0cfg;
432	unsigned int tlb0ps;
433	unsigned int eptcfg;
434	int i, psize;
435
436#ifdef CONFIG_PPC_FSL_BOOK3E
437	unsigned int mmucfg = mfspr(SPRN_MMUCFG);
438	int fsl_mmu = mmu_has_feature(MMU_FTR_TYPE_FSL_E);
439
440	if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V1) {
441		unsigned int tlb1cfg = mfspr(SPRN_TLB1CFG);
442		unsigned int min_pg, max_pg;
443
444		min_pg = (tlb1cfg & TLBnCFG_MINSIZE) >> TLBnCFG_MINSIZE_SHIFT;
445		max_pg = (tlb1cfg & TLBnCFG_MAXSIZE) >> TLBnCFG_MAXSIZE_SHIFT;
446
447		for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
448			struct mmu_psize_def *def;
449			unsigned int shift;
450
451			def = &mmu_psize_defs[psize];
452			shift = def->shift;
453
454			if (shift == 0 || shift & 1)
455				continue;
456
457			/* adjust to be in terms of 4^shift Kb */
458			shift = (shift - 10) >> 1;
459
460			if ((shift >= min_pg) && (shift <= max_pg))
461				def->flags |= MMU_PAGE_SIZE_DIRECT;
462		}
463
464		goto out;
465	}
466
467	if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V2) {
468		u32 tlb1cfg, tlb1ps;
469
470		tlb0cfg = mfspr(SPRN_TLB0CFG);
471		tlb1cfg = mfspr(SPRN_TLB1CFG);
472		tlb1ps = mfspr(SPRN_TLB1PS);
473		eptcfg = mfspr(SPRN_EPTCFG);
474
475		if ((tlb1cfg & TLBnCFG_IND) && (tlb0cfg & TLBnCFG_PT))
476			book3e_htw_mode = PPC_HTW_E6500;
477
478		/*
479		 * We expect 4K subpage size and unrestricted indirect size.
480		 * The lack of a restriction on indirect size is a Freescale
481		 * extension, indicated by PSn = 0 but SPSn != 0.
482		 */
483		if (eptcfg != 2)
484			book3e_htw_mode = PPC_HTW_NONE;
485
486		for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
487			struct mmu_psize_def *def = &mmu_psize_defs[psize];
488
489			if (tlb1ps & (1U << (def->shift - 10))) {
490				def->flags |= MMU_PAGE_SIZE_DIRECT;
491
492				if (book3e_htw_mode && psize == MMU_PAGE_2M)
493					def->flags |= MMU_PAGE_SIZE_INDIRECT;
494			}
495		}
496
497		goto out;
498	}
499#endif
500
501	tlb0cfg = mfspr(SPRN_TLB0CFG);
502	tlb0ps = mfspr(SPRN_TLB0PS);
503	eptcfg = mfspr(SPRN_EPTCFG);
504
505	/* Look for supported direct sizes */
506	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
507		struct mmu_psize_def *def = &mmu_psize_defs[psize];
508
509		if (tlb0ps & (1U << (def->shift - 10)))
510			def->flags |= MMU_PAGE_SIZE_DIRECT;
511	}
512
513	/* Indirect page sizes supported ? */
514	if ((tlb0cfg & TLBnCFG_IND) == 0 ||
515	    (tlb0cfg & TLBnCFG_PT) == 0)
516		goto out;
517
518	book3e_htw_mode = PPC_HTW_IBM;
519
520	/* Now, we only deal with one IND page size for each
521	 * direct size. Hopefully all implementations today are
522	 * unambiguous, but we might want to be careful in the
523	 * future.
524	 */
525	for (i = 0; i < 3; i++) {
526		unsigned int ps, sps;
527
528		sps = eptcfg & 0x1f;
529		eptcfg >>= 5;
530		ps = eptcfg & 0x1f;
531		eptcfg >>= 5;
532		if (!ps || !sps)
533			continue;
534		for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
535			struct mmu_psize_def *def = &mmu_psize_defs[psize];
536
537			if (ps == (def->shift - 10))
538				def->flags |= MMU_PAGE_SIZE_INDIRECT;
539			if (sps == (def->shift - 10))
540				def->ind = ps + 10;
541		}
542	}
543
544out:
545	/* Cleanup array and print summary */
546	pr_info("MMU: Supported page sizes\n");
547	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
548		struct mmu_psize_def *def = &mmu_psize_defs[psize];
549		const char *__page_type_names[] = {
550			"unsupported",
551			"direct",
552			"indirect",
553			"direct & indirect"
554		};
555		if (def->flags == 0) {
556			def->shift = 0;
557			continue;
558		}
559		pr_info("  %8ld KB as %s\n", 1ul << (def->shift - 10),
560			__page_type_names[def->flags & 0x3]);
561	}
562}
563
564static void setup_mmu_htw(void)
565{
566	/*
567	 * If we want to use HW tablewalk, enable it by patching the TLB miss
568	 * handlers to branch to the one dedicated to it.
569	 */
570
571	switch (book3e_htw_mode) {
572	case PPC_HTW_IBM:
573		patch_exception(0x1c0, exc_data_tlb_miss_htw_book3e);
574		patch_exception(0x1e0, exc_instruction_tlb_miss_htw_book3e);
575		break;
576#ifdef CONFIG_PPC_FSL_BOOK3E
577	case PPC_HTW_E6500:
578		extlb_level_exc = EX_TLB_SIZE;
579		patch_exception(0x1c0, exc_data_tlb_miss_e6500_book3e);
580		patch_exception(0x1e0, exc_instruction_tlb_miss_e6500_book3e);
581		break;
582#endif
583	}
584	pr_info("MMU: Book3E HW tablewalk %s\n",
585		book3e_htw_mode != PPC_HTW_NONE ? "enabled" : "not supported");
586}
587
588/*
589 * Early initialization of the MMU TLB code
590 */
591static void early_init_this_mmu(void)
592{
593	unsigned int mas4;
594
595	/* Set MAS4 based on page table setting */
596
597	mas4 = 0x4 << MAS4_WIMGED_SHIFT;
598	switch (book3e_htw_mode) {
599	case PPC_HTW_E6500:
600		mas4 |= MAS4_INDD;
601		mas4 |= BOOK3E_PAGESZ_2M << MAS4_TSIZED_SHIFT;
602		mas4 |= MAS4_TLBSELD(1);
603		mmu_pte_psize = MMU_PAGE_2M;
604		break;
605
606	case PPC_HTW_IBM:
607		mas4 |= MAS4_INDD;
608#ifdef CONFIG_PPC_64K_PAGES
609		mas4 |=	BOOK3E_PAGESZ_256M << MAS4_TSIZED_SHIFT;
610		mmu_pte_psize = MMU_PAGE_256M;
611#else
612		mas4 |=	BOOK3E_PAGESZ_1M << MAS4_TSIZED_SHIFT;
613		mmu_pte_psize = MMU_PAGE_1M;
614#endif
615		break;
616
617	case PPC_HTW_NONE:
618#ifdef CONFIG_PPC_64K_PAGES
619		mas4 |=	BOOK3E_PAGESZ_64K << MAS4_TSIZED_SHIFT;
620#else
621		mas4 |=	BOOK3E_PAGESZ_4K << MAS4_TSIZED_SHIFT;
622#endif
623		mmu_pte_psize = mmu_virtual_psize;
624		break;
625	}
626	mtspr(SPRN_MAS4, mas4);
627
628#ifdef CONFIG_PPC_FSL_BOOK3E
629	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
630		unsigned int num_cams;
631
632		/* use a quarter of the TLBCAM for bolted linear map */
633		num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4;
634		linear_map_top = map_mem_in_cams(linear_map_top, num_cams);
635	}
636#endif
637
638	/* A sync won't hurt us after mucking around with
639	 * the MMU configuration
640	 */
641	mb();
642}
643
644static void __init early_init_mmu_global(void)
645{
646	/* XXX This will have to be decided at runtime, but right
647	 * now our boot and TLB miss code hard wires it. Ideally
648	 * we should find out a suitable page size and patch the
649	 * TLB miss code (either that or use the PACA to store
650	 * the value we want)
651	 */
652	mmu_linear_psize = MMU_PAGE_1G;
653
654	/* XXX This should be decided at runtime based on supported
655	 * page sizes in the TLB, but for now let's assume 16M is
656	 * always there and a good fit (which it probably is)
657	 *
658	 * Freescale booke only supports 4K pages in TLB0, so use that.
659	 */
660	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
661		mmu_vmemmap_psize = MMU_PAGE_4K;
662	else
663		mmu_vmemmap_psize = MMU_PAGE_16M;
664
665	/* XXX This code only checks for TLB 0 capabilities and doesn't
666	 *     check what page size combos are supported by the HW. It
667	 *     also doesn't handle the case where a separate array holds
668	 *     the IND entries from the array loaded by the PT.
669	 */
670	/* Look for supported page sizes */
671	setup_page_sizes();
672
673	/* Look for HW tablewalk support */
674	setup_mmu_htw();
675
676#ifdef CONFIG_PPC_FSL_BOOK3E
677	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
678		if (book3e_htw_mode == PPC_HTW_NONE) {
679			extlb_level_exc = EX_TLB_SIZE;
680			patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e);
681			patch_exception(0x1e0,
682				exc_instruction_tlb_miss_bolted_book3e);
683		}
684	}
685#endif
686
687	/* Set the global containing the top of the linear mapping
688	 * for use by the TLB miss code
689	 */
690	linear_map_top = memblock_end_of_DRAM();
691}
692
693static void __init early_mmu_set_memory_limit(void)
694{
695#ifdef CONFIG_PPC_FSL_BOOK3E
696	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
697		/*
698		 * Limit memory so we dont have linear faults.
699		 * Unlike memblock_set_current_limit, which limits
700		 * memory available during early boot, this permanently
701		 * reduces the memory available to Linux.  We need to
702		 * do this because highmem is not supported on 64-bit.
703		 */
704		memblock_enforce_memory_limit(linear_map_top);
705	}
706#endif
707
708	memblock_set_current_limit(linear_map_top);
709}
710
711/* boot cpu only */
712void __init early_init_mmu(void)
713{
714	early_init_mmu_global();
715	early_init_this_mmu();
716	early_mmu_set_memory_limit();
717}
718
719void early_init_mmu_secondary(void)
720{
721	early_init_this_mmu();
722}
723
724void setup_initial_memory_limit(phys_addr_t first_memblock_base,
725				phys_addr_t first_memblock_size)
726{
727	/* On non-FSL Embedded 64-bit, we adjust the RMA size to match
728	 * the bolted TLB entry. We know for now that only 1G
729	 * entries are supported though that may eventually
730	 * change.
731	 *
732	 * on FSL Embedded 64-bit, we adjust the RMA size to match the
733	 * first bolted TLB entry size.  We still limit max to 1G even if
734	 * the TLB could cover more.  This is due to what the early init
735	 * code is setup to do.
736	 *
737	 * We crop it to the size of the first MEMBLOCK to
738	 * avoid going over total available memory just in case...
739	 */
740#ifdef CONFIG_PPC_FSL_BOOK3E
741	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
742		unsigned long linear_sz;
743		linear_sz = calc_cam_sz(first_memblock_size, PAGE_OFFSET,
744					first_memblock_base);
745		ppc64_rma_size = min_t(u64, linear_sz, 0x40000000);
746	} else
747#endif
748		ppc64_rma_size = min_t(u64, first_memblock_size, 0x40000000);
749
750	/* Finally limit subsequent allocations */
751	memblock_set_current_limit(first_memblock_base + ppc64_rma_size);
752}
753#else /* ! CONFIG_PPC64 */
754void __init early_init_mmu(void)
755{
756#ifdef CONFIG_PPC_47x
757	early_init_mmu_47x();
758#endif
759}
760#endif /* CONFIG_PPC64 */
761