xref: /linux/arch/mips/mm/init.c (revision b0148a98ec5151fec82064d95f11eb9efbc628ea)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1994 - 2000 Ralf Baechle
7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
9  * Copyright (C) 2000 MIPS Technologies, Inc.  All rights reserved.
10  */
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/signal.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
16 #include <linux/errno.h>
17 #include <linux/string.h>
18 #include <linux/types.h>
19 #include <linux/pagemap.h>
20 #include <linux/ptrace.h>
21 #include <linux/mman.h>
22 #include <linux/mm.h>
23 #include <linux/bootmem.h>
24 #include <linux/highmem.h>
25 #include <linux/swap.h>
26 #include <linux/proc_fs.h>
27 #include <linux/pfn.h>
28 
29 #include <asm/bootinfo.h>
30 #include <asm/cachectl.h>
31 #include <asm/cpu.h>
32 #include <asm/dma.h>
33 #include <asm/kmap_types.h>
34 #include <asm/mmu_context.h>
35 #include <asm/sections.h>
36 #include <asm/pgtable.h>
37 #include <asm/pgalloc.h>
38 #include <asm/tlb.h>
39 #include <asm/fixmap.h>
40 
41 /* Atomicity and interruptability */
42 #ifdef CONFIG_MIPS_MT_SMTC
43 
44 #include <asm/mipsmtregs.h>
45 
46 #define ENTER_CRITICAL(flags) \
47 	{ \
48 	unsigned int mvpflags; \
49 	local_irq_save(flags);\
50 	mvpflags = dvpe()
51 #define EXIT_CRITICAL(flags) \
52 	evpe(mvpflags); \
53 	local_irq_restore(flags); \
54 	}
55 #else
56 
57 #define ENTER_CRITICAL(flags) local_irq_save(flags)
58 #define EXIT_CRITICAL(flags) local_irq_restore(flags)
59 
60 #endif /* CONFIG_MIPS_MT_SMTC */
61 
62 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
63 
64 unsigned long highstart_pfn, highend_pfn;
65 
66 /*
67  * We have up to 8 empty zeroed pages so we can map one of the right colour
68  * when needed.  This is necessary only on R4000 / R4400 SC and MC versions
69  * where we have to avoid VCED / VECI exceptions for good performance at
70  * any price.  Since page is never written to after the initialization we
71  * don't have to care about aliases on other CPUs.
72  */
73 unsigned long empty_zero_page, zero_page_mask;
74 
75 /*
76  * Not static inline because used by IP27 special magic initialization code
77  */
78 unsigned long setup_zero_pages(void)
79 {
80 	unsigned int order;
81 	unsigned long size;
82 	struct page *page;
83 
84 	if (cpu_has_vce)
85 		order = 3;
86 	else
87 		order = 0;
88 
89 	empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
90 	if (!empty_zero_page)
91 		panic("Oh boy, that early out of memory?");
92 
93 	page = virt_to_page((void *)empty_zero_page);
94 	split_page(page, order);
95 	while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) {
96 		SetPageReserved(page);
97 		page++;
98 	}
99 
100 	size = PAGE_SIZE << order;
101 	zero_page_mask = (size - 1) & PAGE_MASK;
102 
103 	return 1UL << order;
104 }
105 
106 /*
107  * These are almost like kmap_atomic / kunmap_atmic except they take an
108  * additional address argument as the hint.
109  */
110 
111 #define kmap_get_fixmap_pte(vaddr)					\
112 	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
113 
114 #ifdef CONFIG_MIPS_MT_SMTC
115 static pte_t *kmap_coherent_pte;
116 static void __init kmap_coherent_init(void)
117 {
118 	unsigned long vaddr;
119 
120 	/* cache the first coherent kmap pte */
121 	vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
122 	kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
123 }
124 #else
125 static inline void kmap_coherent_init(void) {}
126 #endif
127 
128 static inline void *kmap_coherent(struct page *page, unsigned long addr)
129 {
130 	enum fixed_addresses idx;
131 	unsigned long vaddr, flags, entrylo;
132 	unsigned long old_ctx;
133 	pte_t pte;
134 	int tlbidx;
135 
136 	inc_preempt_count();
137 	idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
138 #ifdef CONFIG_MIPS_MT_SMTC
139 	idx += FIX_N_COLOURS * smp_processor_id();
140 #endif
141 	vaddr = __fix_to_virt(FIX_CMAP_END - idx);
142 	pte = mk_pte(page, PAGE_KERNEL);
143 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32_R1)
144 	entrylo = pte.pte_high;
145 #else
146 	entrylo = pte_val(pte) >> 6;
147 #endif
148 
149 	ENTER_CRITICAL(flags);
150 	old_ctx = read_c0_entryhi();
151 	write_c0_entryhi(vaddr & (PAGE_MASK << 1));
152 	write_c0_entrylo0(entrylo);
153 	write_c0_entrylo1(entrylo);
154 #ifdef CONFIG_MIPS_MT_SMTC
155 	set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
156 	/* preload TLB instead of local_flush_tlb_one() */
157 	mtc0_tlbw_hazard();
158 	tlb_probe();
159 	tlb_probe_hazard();
160 	tlbidx = read_c0_index();
161 	mtc0_tlbw_hazard();
162 	if (tlbidx < 0)
163 		tlb_write_random();
164 	else
165 		tlb_write_indexed();
166 #else
167 	tlbidx = read_c0_wired();
168 	write_c0_wired(tlbidx + 1);
169 	write_c0_index(tlbidx);
170 	mtc0_tlbw_hazard();
171 	tlb_write_indexed();
172 #endif
173 	tlbw_use_hazard();
174 	write_c0_entryhi(old_ctx);
175 	EXIT_CRITICAL(flags);
176 
177 	return (void*) vaddr;
178 }
179 
180 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1)))
181 
182 static inline void kunmap_coherent(struct page *page)
183 {
184 #ifndef CONFIG_MIPS_MT_SMTC
185 	unsigned int wired;
186 	unsigned long flags, old_ctx;
187 
188 	ENTER_CRITICAL(flags);
189 	old_ctx = read_c0_entryhi();
190 	wired = read_c0_wired() - 1;
191 	write_c0_wired(wired);
192 	write_c0_index(wired);
193 	write_c0_entryhi(UNIQUE_ENTRYHI(wired));
194 	write_c0_entrylo0(0);
195 	write_c0_entrylo1(0);
196 	mtc0_tlbw_hazard();
197 	tlb_write_indexed();
198 	tlbw_use_hazard();
199 	write_c0_entryhi(old_ctx);
200 	EXIT_CRITICAL(flags);
201 #endif
202 	dec_preempt_count();
203 	preempt_check_resched();
204 }
205 
206 void copy_user_highpage(struct page *to, struct page *from,
207 	unsigned long vaddr, struct vm_area_struct *vma)
208 {
209 	void *vfrom, *vto;
210 
211 	vto = kmap_atomic(to, KM_USER1);
212 	if (cpu_has_dc_aliases) {
213 		vfrom = kmap_coherent(from, vaddr);
214 		copy_page(vto, vfrom);
215 		kunmap_coherent(from);
216 	} else {
217 		vfrom = kmap_atomic(from, KM_USER0);
218 		copy_page(vto, vfrom);
219 		kunmap_atomic(vfrom, KM_USER0);
220 	}
221 	if (((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) ||
222 	    pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
223 		flush_data_cache_page((unsigned long)vto);
224 	kunmap_atomic(vto, KM_USER1);
225 	/* Make sure this page is cleared on other CPU's too before using it */
226 	smp_wmb();
227 }
228 
229 EXPORT_SYMBOL(copy_user_highpage);
230 
231 void copy_to_user_page(struct vm_area_struct *vma,
232 	struct page *page, unsigned long vaddr, void *dst, const void *src,
233 	unsigned long len)
234 {
235 	if (cpu_has_dc_aliases) {
236 		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
237 		memcpy(vto, src, len);
238 		kunmap_coherent(page);
239 	} else
240 		memcpy(dst, src, len);
241 	if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
242 		flush_cache_page(vma, vaddr, page_to_pfn(page));
243 }
244 
245 EXPORT_SYMBOL(copy_to_user_page);
246 
247 void copy_from_user_page(struct vm_area_struct *vma,
248 	struct page *page, unsigned long vaddr, void *dst, const void *src,
249 	unsigned long len)
250 {
251 	if (cpu_has_dc_aliases) {
252 		void *vfrom =
253 			kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
254 		memcpy(dst, vfrom, len);
255 		kunmap_coherent(page);
256 	} else
257 		memcpy(dst, src, len);
258 }
259 
260 EXPORT_SYMBOL(copy_from_user_page);
261 
262 
263 #ifdef CONFIG_HIGHMEM
264 pte_t *kmap_pte;
265 pgprot_t kmap_prot;
266 
267 static void __init kmap_init(void)
268 {
269 	unsigned long kmap_vstart;
270 
271 	/* cache the first kmap pte */
272 	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
273 	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
274 
275 	kmap_prot = PAGE_KERNEL;
276 }
277 #endif /* CONFIG_HIGHMEM */
278 
279 void __init fixrange_init(unsigned long start, unsigned long end,
280 	pgd_t *pgd_base)
281 {
282 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC)
283 	pgd_t *pgd;
284 	pud_t *pud;
285 	pmd_t *pmd;
286 	pte_t *pte;
287 	int i, j, k;
288 	unsigned long vaddr;
289 
290 	vaddr = start;
291 	i = __pgd_offset(vaddr);
292 	j = __pud_offset(vaddr);
293 	k = __pmd_offset(vaddr);
294 	pgd = pgd_base + i;
295 
296 	for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
297 		pud = (pud_t *)pgd;
298 		for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
299 			pmd = (pmd_t *)pud;
300 			for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
301 				if (pmd_none(*pmd)) {
302 					pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
303 					set_pmd(pmd, __pmd((unsigned long)pte));
304 					if (pte != pte_offset_kernel(pmd, 0))
305 						BUG();
306 				}
307 				vaddr += PMD_SIZE;
308 			}
309 			k = 0;
310 		}
311 		j = 0;
312 	}
313 #endif
314 }
315 
316 #ifndef CONFIG_NEED_MULTIPLE_NODES
317 extern void pagetable_init(void);
318 
319 static int __init page_is_ram(unsigned long pagenr)
320 {
321 	int i;
322 
323 	for (i = 0; i < boot_mem_map.nr_map; i++) {
324 		unsigned long addr, end;
325 
326 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
327 			/* not usable memory */
328 			continue;
329 
330 		addr = PFN_UP(boot_mem_map.map[i].addr);
331 		end = PFN_DOWN(boot_mem_map.map[i].addr +
332 			       boot_mem_map.map[i].size);
333 
334 		if (pagenr >= addr && pagenr < end)
335 			return 1;
336 	}
337 
338 	return 0;
339 }
340 
341 void __init paging_init(void)
342 {
343 	unsigned long zones_size[MAX_NR_ZONES] = { 0, };
344 #ifndef CONFIG_FLATMEM
345 	unsigned long zholes_size[MAX_NR_ZONES] = { 0, };
346 	unsigned long i, j, pfn;
347 #endif
348 
349 	pagetable_init();
350 
351 #ifdef CONFIG_HIGHMEM
352 	kmap_init();
353 #endif
354 	kmap_coherent_init();
355 
356 #ifdef CONFIG_ISA
357 	if (max_low_pfn >= MAX_DMA_PFN)
358 		if (min_low_pfn >= MAX_DMA_PFN) {
359 			zones_size[ZONE_DMA] = 0;
360 			zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
361 		} else {
362 			zones_size[ZONE_DMA] = MAX_DMA_PFN - min_low_pfn;
363 			zones_size[ZONE_NORMAL] = max_low_pfn - MAX_DMA_PFN;
364 		}
365 	else
366 #endif
367 	zones_size[ZONE_DMA] = max_low_pfn - min_low_pfn;
368 
369 #ifdef CONFIG_HIGHMEM
370 	zones_size[ZONE_HIGHMEM] = highend_pfn - highstart_pfn;
371 
372 	if (cpu_has_dc_aliases && zones_size[ZONE_HIGHMEM]) {
373 		printk(KERN_WARNING "This processor doesn't support highmem."
374 		       " %ldk highmem ignored\n", zones_size[ZONE_HIGHMEM]);
375 		zones_size[ZONE_HIGHMEM] = 0;
376 	}
377 #endif
378 
379 #ifdef CONFIG_FLATMEM
380 	free_area_init(zones_size);
381 #else
382 	pfn = 0;
383 	for (i = 0; i < MAX_NR_ZONES; i++)
384 		for (j = 0; j < zones_size[i]; j++, pfn++)
385 			if (!page_is_ram(pfn))
386 				zholes_size[i]++;
387 	free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size);
388 #endif
389 }
390 
391 static struct kcore_list kcore_mem, kcore_vmalloc;
392 #ifdef CONFIG_64BIT
393 static struct kcore_list kcore_kseg0;
394 #endif
395 
396 void __init mem_init(void)
397 {
398 	unsigned long codesize, reservedpages, datasize, initsize;
399 	unsigned long tmp, ram;
400 
401 #ifdef CONFIG_HIGHMEM
402 #ifdef CONFIG_DISCONTIGMEM
403 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
404 #endif
405 	max_mapnr = highend_pfn;
406 #else
407 	max_mapnr = max_low_pfn;
408 #endif
409 	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
410 
411 	totalram_pages += free_all_bootmem();
412 	totalram_pages -= setup_zero_pages();	/* Setup zeroed pages.  */
413 
414 	reservedpages = ram = 0;
415 	for (tmp = 0; tmp < max_low_pfn; tmp++)
416 		if (page_is_ram(tmp)) {
417 			ram++;
418 			if (PageReserved(pfn_to_page(tmp)))
419 				reservedpages++;
420 		}
421 	num_physpages = ram;
422 
423 #ifdef CONFIG_HIGHMEM
424 	for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
425 		struct page *page = mem_map + tmp;
426 
427 		if (!page_is_ram(tmp)) {
428 			SetPageReserved(page);
429 			continue;
430 		}
431 		ClearPageReserved(page);
432 #ifdef CONFIG_LIMITED_DMA
433 		set_page_address(page, lowmem_page_address(page));
434 #endif
435 		init_page_count(page);
436 		__free_page(page);
437 		totalhigh_pages++;
438 	}
439 	totalram_pages += totalhigh_pages;
440 	num_physpages += totalhigh_pages;
441 #endif
442 
443 	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
444 	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
445 	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
446 
447 #ifdef CONFIG_64BIT
448 	if ((unsigned long) &_text > (unsigned long) CKSEG0)
449 		/* The -4 is a hack so that user tools don't have to handle
450 		   the overflow.  */
451 		kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4);
452 #endif
453 	kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
454 	kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
455 		   VMALLOC_END-VMALLOC_START);
456 
457 	printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
458 	       "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
459 	       (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
460 	       ram << (PAGE_SHIFT-10),
461 	       codesize >> 10,
462 	       reservedpages << (PAGE_SHIFT-10),
463 	       datasize >> 10,
464 	       initsize >> 10,
465 	       (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
466 }
467 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
468 
469 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
470 {
471 	unsigned long pfn;
472 
473 	for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
474 		struct page *page = pfn_to_page(pfn);
475 		void *addr = phys_to_virt(PFN_PHYS(pfn));
476 
477 		ClearPageReserved(page);
478 		init_page_count(page);
479 		memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
480 		__free_page(page);
481 		totalram_pages++;
482 	}
483 	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
484 }
485 
486 #ifdef CONFIG_BLK_DEV_INITRD
487 void free_initrd_mem(unsigned long start, unsigned long end)
488 {
489 	free_init_pages("initrd memory",
490 			virt_to_phys((void *)start),
491 			virt_to_phys((void *)end));
492 }
493 #endif
494 
495 void free_initmem(void)
496 {
497 	prom_free_prom_memory();
498 	free_init_pages("unused kernel memory",
499 			__pa_symbol(&__init_begin),
500 			__pa_symbol(&__init_end));
501 }
502 
503 unsigned long pgd_current[NR_CPUS];
504 /*
505  * On 64-bit we've got three-level pagetables with a slightly
506  * different layout ...
507  */
508 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
509 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER);
510 #ifdef CONFIG_64BIT
511 #ifdef MODULE_START
512 pgd_t module_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER);
513 #endif
514 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER);
515 #endif
516 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);
517