1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * This file contains the routines for TLB flushing.
4 * On machines where the MMU does not use a hash table to store virtual to
5 * physical translations (ie, SW loaded TLBs or Book3E compilant processors,
6 * this does -not- include 603 however which shares the implementation with
7 * hash based processors)
8 *
9 *  -- BenH
10 *
11 * Copyright 2008,2009 Ben Herrenschmidt <benh@kernel.crashing.org>
12 *                     IBM Corp.
13 *
14 *  Derived from arch/ppc/mm/init.c:
15 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
16 *
17 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
18 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
19 *    Copyright (C) 1996 Paul Mackerras
20 *
21 *  Derived from "arch/i386/mm/init.c"
22 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
23 */
24
25#include <linux/kernel.h>
26#include <linux/export.h>
27#include <linux/mm.h>
28#include <linux/init.h>
29#include <linux/highmem.h>
30#include <linux/pagemap.h>
31#include <linux/preempt.h>
32#include <linux/spinlock.h>
33#include <linux/memblock.h>
34#include <linux/of_fdt.h>
35#include <linux/hugetlb.h>
36
37#include <asm/pgalloc.h>
38#include <asm/tlbflush.h>
39#include <asm/tlb.h>
40#include <asm/code-patching.h>
41#include <asm/cputhreads.h>
42#include <asm/hugetlb.h>
43#include <asm/paca.h>
44
45#include <mm/mmu_decl.h>
46
47/*
48 * This struct lists the sw-supported page sizes.  The hardawre MMU may support
49 * other sizes not listed here.   The .ind field is only used on MMUs that have
50 * indirect page table entries.
51 */
52#if defined(CONFIG_PPC_BOOK3E_MMU) || defined(CONFIG_PPC_8xx)
53#ifdef CONFIG_PPC_FSL_BOOK3E
54struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
55	[MMU_PAGE_4K] = {
56		.shift	= 12,
57		.enc	= BOOK3E_PAGESZ_4K,
58	},
59	[MMU_PAGE_2M] = {
60		.shift	= 21,
61		.enc	= BOOK3E_PAGESZ_2M,
62	},
63	[MMU_PAGE_4M] = {
64		.shift	= 22,
65		.enc	= BOOK3E_PAGESZ_4M,
66	},
67	[MMU_PAGE_16M] = {
68		.shift	= 24,
69		.enc	= BOOK3E_PAGESZ_16M,
70	},
71	[MMU_PAGE_64M] = {
72		.shift	= 26,
73		.enc	= BOOK3E_PAGESZ_64M,
74	},
75	[MMU_PAGE_256M] = {
76		.shift	= 28,
77		.enc	= BOOK3E_PAGESZ_256M,
78	},
79	[MMU_PAGE_1G] = {
80		.shift	= 30,
81		.enc	= BOOK3E_PAGESZ_1GB,
82	},
83};
84#elif defined(CONFIG_PPC_8xx)
85struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
86	[MMU_PAGE_4K] = {
87		.shift	= 12,
88	},
89	[MMU_PAGE_16K] = {
90		.shift	= 14,
91	},
92	[MMU_PAGE_512K] = {
93		.shift	= 19,
94	},
95	[MMU_PAGE_8M] = {
96		.shift	= 23,
97	},
98};
99#else
100struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
101	[MMU_PAGE_4K] = {
102		.shift	= 12,
103		.ind	= 20,
104		.enc	= BOOK3E_PAGESZ_4K,
105	},
106	[MMU_PAGE_16K] = {
107		.shift	= 14,
108		.enc	= BOOK3E_PAGESZ_16K,
109	},
110	[MMU_PAGE_64K] = {
111		.shift	= 16,
112		.ind	= 28,
113		.enc	= BOOK3E_PAGESZ_64K,
114	},
115	[MMU_PAGE_1M] = {
116		.shift	= 20,
117		.enc	= BOOK3E_PAGESZ_1M,
118	},
119	[MMU_PAGE_16M] = {
120		.shift	= 24,
121		.ind	= 36,
122		.enc	= BOOK3E_PAGESZ_16M,
123	},
124	[MMU_PAGE_256M] = {
125		.shift	= 28,
126		.enc	= BOOK3E_PAGESZ_256M,
127	},
128	[MMU_PAGE_1G] = {
129		.shift	= 30,
130		.enc	= BOOK3E_PAGESZ_1GB,
131	},
132};
133#endif /* CONFIG_FSL_BOOKE */
134
135static inline int mmu_get_tsize(int psize)
136{
137	return mmu_psize_defs[psize].enc;
138}
139#else
140static inline int mmu_get_tsize(int psize)
141{
142	/* This isn't used on !Book3E for now */
143	return 0;
144}
145#endif /* CONFIG_PPC_BOOK3E_MMU */
146
147/* The variables below are currently only used on 64-bit Book3E
148 * though this will probably be made common with other nohash
149 * implementations at some point
150 */
151#ifdef CONFIG_PPC64
152
153int mmu_linear_psize;		/* Page size used for the linear mapping */
154int mmu_pte_psize;		/* Page size used for PTE pages */
155int mmu_vmemmap_psize;		/* Page size used for the virtual mem map */
156int book3e_htw_mode;		/* HW tablewalk?  Value is PPC_HTW_* */
157unsigned long linear_map_top;	/* Top of linear mapping */
158
159
160/*
161 * Number of bytes to add to SPRN_SPRG_TLB_EXFRAME on crit/mcheck/debug
162 * exceptions.  This is used for bolted and e6500 TLB miss handlers which
163 * do not modify this SPRG in the TLB miss code; for other TLB miss handlers,
164 * this is set to zero.
165 */
166int extlb_level_exc;
167
168#endif /* CONFIG_PPC64 */
169
170#ifdef CONFIG_PPC_FSL_BOOK3E
171/* next_tlbcam_idx is used to round-robin tlbcam entry assignment */
172DEFINE_PER_CPU(int, next_tlbcam_idx);
173EXPORT_PER_CPU_SYMBOL(next_tlbcam_idx);
174#endif
175
176/*
177 * Base TLB flushing operations:
178 *
179 *  - flush_tlb_mm(mm) flushes the specified mm context TLB's
180 *  - flush_tlb_page(vma, vmaddr) flushes one page
181 *  - flush_tlb_range(vma, start, end) flushes a range of pages
182 *  - flush_tlb_kernel_range(start, end) flushes kernel pages
183 *
184 *  - local_* variants of page and mm only apply to the current
185 *    processor
186 */
187
188/*
189 * These are the base non-SMP variants of page and mm flushing
190 */
191void local_flush_tlb_mm(struct mm_struct *mm)
192{
193	unsigned int pid;
194
195	preempt_disable();
196	pid = mm->context.id;
197	if (pid != MMU_NO_CONTEXT)
198		_tlbil_pid(pid);
199	preempt_enable();
200}
201EXPORT_SYMBOL(local_flush_tlb_mm);
202
203void __local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
204			    int tsize, int ind)
205{
206	unsigned int pid;
207
208	preempt_disable();
209	pid = mm ? mm->context.id : 0;
210	if (pid != MMU_NO_CONTEXT)
211		_tlbil_va(vmaddr, pid, tsize, ind);
212	preempt_enable();
213}
214
215void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
216{
217	__local_flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
218			       mmu_get_tsize(mmu_virtual_psize), 0);
219}
220EXPORT_SYMBOL(local_flush_tlb_page);
221
222/*
223 * And here are the SMP non-local implementations
224 */
225#ifdef CONFIG_SMP
226
227static DEFINE_RAW_SPINLOCK(tlbivax_lock);
228
229struct tlb_flush_param {
230	unsigned long addr;
231	unsigned int pid;
232	unsigned int tsize;
233	unsigned int ind;
234};
235
236static void do_flush_tlb_mm_ipi(void *param)
237{
238	struct tlb_flush_param *p = param;
239
240	_tlbil_pid(p ? p->pid : 0);
241}
242
243static void do_flush_tlb_page_ipi(void *param)
244{
245	struct tlb_flush_param *p = param;
246
247	_tlbil_va(p->addr, p->pid, p->tsize, p->ind);
248}
249
250
251/* Note on invalidations and PID:
252 *
253 * We snapshot the PID with preempt disabled. At this point, it can still
254 * change either because:
255 * - our context is being stolen (PID -> NO_CONTEXT) on another CPU
256 * - we are invaliating some target that isn't currently running here
257 *   and is concurrently acquiring a new PID on another CPU
258 * - some other CPU is re-acquiring a lost PID for this mm
259 * etc...
260 *
261 * However, this shouldn't be a problem as we only guarantee
262 * invalidation of TLB entries present prior to this call, so we
263 * don't care about the PID changing, and invalidating a stale PID
264 * is generally harmless.
265 */
266
267void flush_tlb_mm(struct mm_struct *mm)
268{
269	unsigned int pid;
270
271	preempt_disable();
272	pid = mm->context.id;
273	if (unlikely(pid == MMU_NO_CONTEXT))
274		goto no_context;
275	if (!mm_is_core_local(mm)) {
276		struct tlb_flush_param p = { .pid = pid };
277		/* Ignores smp_processor_id() even if set. */
278		smp_call_function_many(mm_cpumask(mm),
279				       do_flush_tlb_mm_ipi, &p, 1);
280	}
281	_tlbil_pid(pid);
282 no_context:
283	preempt_enable();
284}
285EXPORT_SYMBOL(flush_tlb_mm);
286
287void __flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
288		      int tsize, int ind)
289{
290	struct cpumask *cpu_mask;
291	unsigned int pid;
292
293	/*
294	 * This function as well as __local_flush_tlb_page() must only be called
295	 * for user contexts.
296	 */
297	if (WARN_ON(!mm))
298		return;
299
300	preempt_disable();
301	pid = mm->context.id;
302	if (unlikely(pid == MMU_NO_CONTEXT))
303		goto bail;
304	cpu_mask = mm_cpumask(mm);
305	if (!mm_is_core_local(mm)) {
306		/* If broadcast tlbivax is supported, use it */
307		if (mmu_has_feature(MMU_FTR_USE_TLBIVAX_BCAST)) {
308			int lock = mmu_has_feature(MMU_FTR_LOCK_BCAST_INVAL);
309			if (lock)
310				raw_spin_lock(&tlbivax_lock);
311			_tlbivax_bcast(vmaddr, pid, tsize, ind);
312			if (lock)
313				raw_spin_unlock(&tlbivax_lock);
314			goto bail;
315		} else {
316			struct tlb_flush_param p = {
317				.pid = pid,
318				.addr = vmaddr,
319				.tsize = tsize,
320				.ind = ind,
321			};
322			/* Ignores smp_processor_id() even if set in cpu_mask */
323			smp_call_function_many(cpu_mask,
324					       do_flush_tlb_page_ipi, &p, 1);
325		}
326	}
327	_tlbil_va(vmaddr, pid, tsize, ind);
328 bail:
329	preempt_enable();
330}
331
332void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
333{
334#ifdef CONFIG_HUGETLB_PAGE
335	if (vma && is_vm_hugetlb_page(vma))
336		flush_hugetlb_page(vma, vmaddr);
337#endif
338
339	__flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
340			 mmu_get_tsize(mmu_virtual_psize), 0);
341}
342EXPORT_SYMBOL(flush_tlb_page);
343
344#endif /* CONFIG_SMP */
345
346#ifdef CONFIG_PPC_47x
347void __init early_init_mmu_47x(void)
348{
349#ifdef CONFIG_SMP
350	unsigned long root = of_get_flat_dt_root();
351	if (of_get_flat_dt_prop(root, "cooperative-partition", NULL))
352		mmu_clear_feature(MMU_FTR_USE_TLBIVAX_BCAST);
353#endif /* CONFIG_SMP */
354}
355#endif /* CONFIG_PPC_47x */
356
357/*
358 * Flush kernel TLB entries in the given range
359 */
360void flush_tlb_kernel_range(unsigned long start, unsigned long end)
361{
362#ifdef CONFIG_SMP
363	preempt_disable();
364	smp_call_function(do_flush_tlb_mm_ipi, NULL, 1);
365	_tlbil_pid(0);
366	preempt_enable();
367#else
368	_tlbil_pid(0);
369#endif
370}
371EXPORT_SYMBOL(flush_tlb_kernel_range);
372
373/*
374 * Currently, for range flushing, we just do a full mm flush. This should
375 * be optimized based on a threshold on the size of the range, since
376 * some implementation can stack multiple tlbivax before a tlbsync but
377 * for now, we keep it that way
378 */
379void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
380		     unsigned long end)
381
382{
383	if (end - start == PAGE_SIZE && !(start & ~PAGE_MASK))
384		flush_tlb_page(vma, start);
385	else
386		flush_tlb_mm(vma->vm_mm);
387}
388EXPORT_SYMBOL(flush_tlb_range);
389
390void tlb_flush(struct mmu_gather *tlb)
391{
392	flush_tlb_mm(tlb->mm);
393}
394
395/*
396 * Below are functions specific to the 64-bit variant of Book3E though that
397 * may change in the future
398 */
399
400#ifdef CONFIG_PPC64
401
402/*
403 * Handling of virtual linear page tables or indirect TLB entries
404 * flushing when PTE pages are freed
405 */
406void tlb_flush_pgtable(struct mmu_gather *tlb, unsigned long address)
407{
408	int tsize = mmu_psize_defs[mmu_pte_psize].enc;
409
410	if (book3e_htw_mode != PPC_HTW_NONE) {
411		unsigned long start = address & PMD_MASK;
412		unsigned long end = address + PMD_SIZE;
413		unsigned long size = 1UL << mmu_psize_defs[mmu_pte_psize].shift;
414
415		/* This isn't the most optimal, ideally we would factor out the
416		 * while preempt & CPU mask mucking around, or even the IPI but
417		 * it will do for now
418		 */
419		while (start < end) {
420			__flush_tlb_page(tlb->mm, start, tsize, 1);
421			start += size;
422		}
423	} else {
424		unsigned long rmask = 0xf000000000000000ul;
425		unsigned long rid = (address & rmask) | 0x1000000000000000ul;
426		unsigned long vpte = address & ~rmask;
427
428		vpte = (vpte >> (PAGE_SHIFT - 3)) & ~0xffful;
429		vpte |= rid;
430		__flush_tlb_page(tlb->mm, vpte, tsize, 0);
431	}
432}
433
434static void setup_page_sizes(void)
435{
436	unsigned int tlb0cfg;
437	unsigned int tlb0ps;
438	unsigned int eptcfg;
439	int i, psize;
440
441#ifdef CONFIG_PPC_FSL_BOOK3E
442	unsigned int mmucfg = mfspr(SPRN_MMUCFG);
443	int fsl_mmu = mmu_has_feature(MMU_FTR_TYPE_FSL_E);
444
445	if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V1) {
446		unsigned int tlb1cfg = mfspr(SPRN_TLB1CFG);
447		unsigned int min_pg, max_pg;
448
449		min_pg = (tlb1cfg & TLBnCFG_MINSIZE) >> TLBnCFG_MINSIZE_SHIFT;
450		max_pg = (tlb1cfg & TLBnCFG_MAXSIZE) >> TLBnCFG_MAXSIZE_SHIFT;
451
452		for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
453			struct mmu_psize_def *def;
454			unsigned int shift;
455
456			def = &mmu_psize_defs[psize];
457			shift = def->shift;
458
459			if (shift == 0 || shift & 1)
460				continue;
461
462			/* adjust to be in terms of 4^shift Kb */
463			shift = (shift - 10) >> 1;
464
465			if ((shift >= min_pg) && (shift <= max_pg))
466				def->flags |= MMU_PAGE_SIZE_DIRECT;
467		}
468
469		goto out;
470	}
471
472	if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V2) {
473		u32 tlb1cfg, tlb1ps;
474
475		tlb0cfg = mfspr(SPRN_TLB0CFG);
476		tlb1cfg = mfspr(SPRN_TLB1CFG);
477		tlb1ps = mfspr(SPRN_TLB1PS);
478		eptcfg = mfspr(SPRN_EPTCFG);
479
480		if ((tlb1cfg & TLBnCFG_IND) && (tlb0cfg & TLBnCFG_PT))
481			book3e_htw_mode = PPC_HTW_E6500;
482
483		/*
484		 * We expect 4K subpage size and unrestricted indirect size.
485		 * The lack of a restriction on indirect size is a Freescale
486		 * extension, indicated by PSn = 0 but SPSn != 0.
487		 */
488		if (eptcfg != 2)
489			book3e_htw_mode = PPC_HTW_NONE;
490
491		for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
492			struct mmu_psize_def *def = &mmu_psize_defs[psize];
493
494			if (!def->shift)
495				continue;
496
497			if (tlb1ps & (1U << (def->shift - 10))) {
498				def->flags |= MMU_PAGE_SIZE_DIRECT;
499
500				if (book3e_htw_mode && psize == MMU_PAGE_2M)
501					def->flags |= MMU_PAGE_SIZE_INDIRECT;
502			}
503		}
504
505		goto out;
506	}
507#endif
508
509	tlb0cfg = mfspr(SPRN_TLB0CFG);
510	tlb0ps = mfspr(SPRN_TLB0PS);
511	eptcfg = mfspr(SPRN_EPTCFG);
512
513	/* Look for supported direct sizes */
514	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
515		struct mmu_psize_def *def = &mmu_psize_defs[psize];
516
517		if (tlb0ps & (1U << (def->shift - 10)))
518			def->flags |= MMU_PAGE_SIZE_DIRECT;
519	}
520
521	/* Indirect page sizes supported ? */
522	if ((tlb0cfg & TLBnCFG_IND) == 0 ||
523	    (tlb0cfg & TLBnCFG_PT) == 0)
524		goto out;
525
526	book3e_htw_mode = PPC_HTW_IBM;
527
528	/* Now, we only deal with one IND page size for each
529	 * direct size. Hopefully all implementations today are
530	 * unambiguous, but we might want to be careful in the
531	 * future.
532	 */
533	for (i = 0; i < 3; i++) {
534		unsigned int ps, sps;
535
536		sps = eptcfg & 0x1f;
537		eptcfg >>= 5;
538		ps = eptcfg & 0x1f;
539		eptcfg >>= 5;
540		if (!ps || !sps)
541			continue;
542		for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
543			struct mmu_psize_def *def = &mmu_psize_defs[psize];
544
545			if (ps == (def->shift - 10))
546				def->flags |= MMU_PAGE_SIZE_INDIRECT;
547			if (sps == (def->shift - 10))
548				def->ind = ps + 10;
549		}
550	}
551
552out:
553	/* Cleanup array and print summary */
554	pr_info("MMU: Supported page sizes\n");
555	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
556		struct mmu_psize_def *def = &mmu_psize_defs[psize];
557		const char *__page_type_names[] = {
558			"unsupported",
559			"direct",
560			"indirect",
561			"direct & indirect"
562		};
563		if (def->flags == 0) {
564			def->shift = 0;
565			continue;
566		}
567		pr_info("  %8ld KB as %s\n", 1ul << (def->shift - 10),
568			__page_type_names[def->flags & 0x3]);
569	}
570}
571
572static void setup_mmu_htw(void)
573{
574	/*
575	 * If we want to use HW tablewalk, enable it by patching the TLB miss
576	 * handlers to branch to the one dedicated to it.
577	 */
578
579	switch (book3e_htw_mode) {
580	case PPC_HTW_IBM:
581		patch_exception(0x1c0, exc_data_tlb_miss_htw_book3e);
582		patch_exception(0x1e0, exc_instruction_tlb_miss_htw_book3e);
583		break;
584#ifdef CONFIG_PPC_FSL_BOOK3E
585	case PPC_HTW_E6500:
586		extlb_level_exc = EX_TLB_SIZE;
587		patch_exception(0x1c0, exc_data_tlb_miss_e6500_book3e);
588		patch_exception(0x1e0, exc_instruction_tlb_miss_e6500_book3e);
589		break;
590#endif
591	}
592	pr_info("MMU: Book3E HW tablewalk %s\n",
593		book3e_htw_mode != PPC_HTW_NONE ? "enabled" : "not supported");
594}
595
596/*
597 * Early initialization of the MMU TLB code
598 */
599static void early_init_this_mmu(void)
600{
601	unsigned int mas4;
602
603	/* Set MAS4 based on page table setting */
604
605	mas4 = 0x4 << MAS4_WIMGED_SHIFT;
606	switch (book3e_htw_mode) {
607	case PPC_HTW_E6500:
608		mas4 |= MAS4_INDD;
609		mas4 |= BOOK3E_PAGESZ_2M << MAS4_TSIZED_SHIFT;
610		mas4 |= MAS4_TLBSELD(1);
611		mmu_pte_psize = MMU_PAGE_2M;
612		break;
613
614	case PPC_HTW_IBM:
615		mas4 |= MAS4_INDD;
616		mas4 |=	BOOK3E_PAGESZ_1M << MAS4_TSIZED_SHIFT;
617		mmu_pte_psize = MMU_PAGE_1M;
618		break;
619
620	case PPC_HTW_NONE:
621		mas4 |=	BOOK3E_PAGESZ_4K << MAS4_TSIZED_SHIFT;
622		mmu_pte_psize = mmu_virtual_psize;
623		break;
624	}
625	mtspr(SPRN_MAS4, mas4);
626
627#ifdef CONFIG_PPC_FSL_BOOK3E
628	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
629		unsigned int num_cams;
630		bool map = true;
631
632		/* use a quarter of the TLBCAM for bolted linear map */
633		num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4;
634
635		/*
636		 * Only do the mapping once per core, or else the
637		 * transient mapping would cause problems.
638		 */
639#ifdef CONFIG_SMP
640		if (hweight32(get_tensr()) > 1)
641			map = false;
642#endif
643
644		if (map)
645			linear_map_top = map_mem_in_cams(linear_map_top,
646							 num_cams, false);
647	}
648#endif
649
650	/* A sync won't hurt us after mucking around with
651	 * the MMU configuration
652	 */
653	mb();
654}
655
656static void __init early_init_mmu_global(void)
657{
658	/* XXX This will have to be decided at runtime, but right
659	 * now our boot and TLB miss code hard wires it. Ideally
660	 * we should find out a suitable page size and patch the
661	 * TLB miss code (either that or use the PACA to store
662	 * the value we want)
663	 */
664	mmu_linear_psize = MMU_PAGE_1G;
665
666	/* XXX This should be decided at runtime based on supported
667	 * page sizes in the TLB, but for now let's assume 16M is
668	 * always there and a good fit (which it probably is)
669	 *
670	 * Freescale booke only supports 4K pages in TLB0, so use that.
671	 */
672	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
673		mmu_vmemmap_psize = MMU_PAGE_4K;
674	else
675		mmu_vmemmap_psize = MMU_PAGE_16M;
676
677	/* XXX This code only checks for TLB 0 capabilities and doesn't
678	 *     check what page size combos are supported by the HW. It
679	 *     also doesn't handle the case where a separate array holds
680	 *     the IND entries from the array loaded by the PT.
681	 */
682	/* Look for supported page sizes */
683	setup_page_sizes();
684
685	/* Look for HW tablewalk support */
686	setup_mmu_htw();
687
688#ifdef CONFIG_PPC_FSL_BOOK3E
689	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
690		if (book3e_htw_mode == PPC_HTW_NONE) {
691			extlb_level_exc = EX_TLB_SIZE;
692			patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e);
693			patch_exception(0x1e0,
694				exc_instruction_tlb_miss_bolted_book3e);
695		}
696	}
697#endif
698
699	/* Set the global containing the top of the linear mapping
700	 * for use by the TLB miss code
701	 */
702	linear_map_top = memblock_end_of_DRAM();
703
704	ioremap_bot = IOREMAP_BASE;
705}
706
707static void __init early_mmu_set_memory_limit(void)
708{
709#ifdef CONFIG_PPC_FSL_BOOK3E
710	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
711		/*
712		 * Limit memory so we dont have linear faults.
713		 * Unlike memblock_set_current_limit, which limits
714		 * memory available during early boot, this permanently
715		 * reduces the memory available to Linux.  We need to
716		 * do this because highmem is not supported on 64-bit.
717		 */
718		memblock_enforce_memory_limit(linear_map_top);
719	}
720#endif
721
722	memblock_set_current_limit(linear_map_top);
723}
724
725/* boot cpu only */
726void __init early_init_mmu(void)
727{
728	early_init_mmu_global();
729	early_init_this_mmu();
730	early_mmu_set_memory_limit();
731}
732
733void early_init_mmu_secondary(void)
734{
735	early_init_this_mmu();
736}
737
738void setup_initial_memory_limit(phys_addr_t first_memblock_base,
739				phys_addr_t first_memblock_size)
740{
741	/* On non-FSL Embedded 64-bit, we adjust the RMA size to match
742	 * the bolted TLB entry. We know for now that only 1G
743	 * entries are supported though that may eventually
744	 * change.
745	 *
746	 * on FSL Embedded 64-bit, usually all RAM is bolted, but with
747	 * unusual memory sizes it's possible for some RAM to not be mapped
748	 * (such RAM is not used at all by Linux, since we don't support
749	 * highmem on 64-bit).  We limit ppc64_rma_size to what would be
750	 * mappable if this memblock is the only one.  Additional memblocks
751	 * can only increase, not decrease, the amount that ends up getting
752	 * mapped.  We still limit max to 1G even if we'll eventually map
753	 * more.  This is due to what the early init code is set up to do.
754	 *
755	 * We crop it to the size of the first MEMBLOCK to
756	 * avoid going over total available memory just in case...
757	 */
758#ifdef CONFIG_PPC_FSL_BOOK3E
759	if (early_mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
760		unsigned long linear_sz;
761		unsigned int num_cams;
762
763		/* use a quarter of the TLBCAM for bolted linear map */
764		num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4;
765
766		linear_sz = map_mem_in_cams(first_memblock_size, num_cams,
767					    true);
768
769		ppc64_rma_size = min_t(u64, linear_sz, 0x40000000);
770	} else
771#endif
772		ppc64_rma_size = min_t(u64, first_memblock_size, 0x40000000);
773
774	/* Finally limit subsequent allocations */
775	memblock_set_current_limit(first_memblock_base + ppc64_rma_size);
776}
777#else /* ! CONFIG_PPC64 */
778void __init early_init_mmu(void)
779{
780#ifdef CONFIG_PPC_47x
781	early_init_mmu_47x();
782#endif
783
784#ifdef CONFIG_PPC_MM_SLICES
785	mm_ctx_set_slb_addr_limit(&init_mm.context, SLB_ADDR_LIMIT_DEFAULT);
786#endif
787}
788#endif /* CONFIG_PPC64 */
789