xref: /linux/arch/mips/mm/init.c (revision 606d099cdd1080bbb50ea50dc52d98252f8f10a1)
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_to_user_page(struct vm_area_struct *vma,
207 	struct page *page, unsigned long vaddr, void *dst, const void *src,
208 	unsigned long len)
209 {
210 	if (cpu_has_dc_aliases) {
211 		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
212 		memcpy(vto, src, len);
213 		kunmap_coherent(page);
214 	} else
215 		memcpy(dst, src, len);
216 	if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
217 		flush_cache_page(vma, vaddr, page_to_pfn(page));
218 }
219 
220 EXPORT_SYMBOL(copy_to_user_page);
221 
222 void copy_from_user_page(struct vm_area_struct *vma,
223 	struct page *page, unsigned long vaddr, void *dst, const void *src,
224 	unsigned long len)
225 {
226 	if (cpu_has_dc_aliases) {
227 		void *vfrom =
228 			kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
229 		memcpy(dst, vfrom, len);
230 		kunmap_coherent(page);
231 	} else
232 		memcpy(dst, src, len);
233 }
234 
235 EXPORT_SYMBOL(copy_from_user_page);
236 
237 
238 #ifdef CONFIG_HIGHMEM
239 pte_t *kmap_pte;
240 pgprot_t kmap_prot;
241 
242 static void __init kmap_init(void)
243 {
244 	unsigned long kmap_vstart;
245 
246 	/* cache the first kmap pte */
247 	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
248 	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
249 
250 	kmap_prot = PAGE_KERNEL;
251 }
252 #endif /* CONFIG_HIGHMEM */
253 
254 void __init fixrange_init(unsigned long start, unsigned long end,
255 	pgd_t *pgd_base)
256 {
257 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC)
258 	pgd_t *pgd;
259 	pud_t *pud;
260 	pmd_t *pmd;
261 	pte_t *pte;
262 	int i, j, k;
263 	unsigned long vaddr;
264 
265 	vaddr = start;
266 	i = __pgd_offset(vaddr);
267 	j = __pud_offset(vaddr);
268 	k = __pmd_offset(vaddr);
269 	pgd = pgd_base + i;
270 
271 	for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
272 		pud = (pud_t *)pgd;
273 		for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
274 			pmd = (pmd_t *)pud;
275 			for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
276 				if (pmd_none(*pmd)) {
277 					pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
278 					set_pmd(pmd, __pmd((unsigned long)pte));
279 					if (pte != pte_offset_kernel(pmd, 0))
280 						BUG();
281 				}
282 				vaddr += PMD_SIZE;
283 			}
284 			k = 0;
285 		}
286 		j = 0;
287 	}
288 #endif
289 }
290 
291 #ifndef CONFIG_NEED_MULTIPLE_NODES
292 extern void pagetable_init(void);
293 
294 static int __init page_is_ram(unsigned long pagenr)
295 {
296 	int i;
297 
298 	for (i = 0; i < boot_mem_map.nr_map; i++) {
299 		unsigned long addr, end;
300 
301 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
302 			/* not usable memory */
303 			continue;
304 
305 		addr = PFN_UP(boot_mem_map.map[i].addr);
306 		end = PFN_DOWN(boot_mem_map.map[i].addr +
307 			       boot_mem_map.map[i].size);
308 
309 		if (pagenr >= addr && pagenr < end)
310 			return 1;
311 	}
312 
313 	return 0;
314 }
315 
316 void __init paging_init(void)
317 {
318 	unsigned long zones_size[MAX_NR_ZONES] = { 0, };
319 	unsigned long max_dma, high, low;
320 #ifndef CONFIG_FLATMEM
321 	unsigned long zholes_size[MAX_NR_ZONES] = { 0, };
322 	unsigned long i, j, pfn;
323 #endif
324 
325 	pagetable_init();
326 
327 #ifdef CONFIG_HIGHMEM
328 	kmap_init();
329 #endif
330 	kmap_coherent_init();
331 
332 	max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
333 	low = max_low_pfn;
334 	high = highend_pfn;
335 
336 #ifdef CONFIG_ISA
337 	if (low < max_dma)
338 		zones_size[ZONE_DMA] = low;
339 	else {
340 		zones_size[ZONE_DMA] = max_dma;
341 		zones_size[ZONE_NORMAL] = low - max_dma;
342 	}
343 #else
344 	zones_size[ZONE_DMA] = low;
345 #endif
346 #ifdef CONFIG_HIGHMEM
347 	if (cpu_has_dc_aliases) {
348 		printk(KERN_WARNING "This processor doesn't support highmem.");
349 		if (high - low)
350 			printk(" %ldk highmem ignored", high - low);
351 		printk("\n");
352 	} else
353 		zones_size[ZONE_HIGHMEM] = high - low;
354 #endif
355 
356 #ifdef CONFIG_FLATMEM
357 	free_area_init(zones_size);
358 #else
359 	pfn = 0;
360 	for (i = 0; i < MAX_NR_ZONES; i++)
361 		for (j = 0; j < zones_size[i]; j++, pfn++)
362 			if (!page_is_ram(pfn))
363 				zholes_size[i]++;
364 	free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size);
365 #endif
366 }
367 
368 static struct kcore_list kcore_mem, kcore_vmalloc;
369 #ifdef CONFIG_64BIT
370 static struct kcore_list kcore_kseg0;
371 #endif
372 
373 void __init mem_init(void)
374 {
375 	unsigned long codesize, reservedpages, datasize, initsize;
376 	unsigned long tmp, ram;
377 
378 #ifdef CONFIG_HIGHMEM
379 #ifdef CONFIG_DISCONTIGMEM
380 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
381 #endif
382 	max_mapnr = highend_pfn;
383 #else
384 	max_mapnr = max_low_pfn;
385 #endif
386 	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
387 
388 	totalram_pages += free_all_bootmem();
389 	totalram_pages -= setup_zero_pages();	/* Setup zeroed pages.  */
390 
391 	reservedpages = ram = 0;
392 	for (tmp = 0; tmp < max_low_pfn; tmp++)
393 		if (page_is_ram(tmp)) {
394 			ram++;
395 			if (PageReserved(pfn_to_page(tmp)))
396 				reservedpages++;
397 		}
398 	num_physpages = ram;
399 
400 #ifdef CONFIG_HIGHMEM
401 	for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
402 		struct page *page = mem_map + tmp;
403 
404 		if (!page_is_ram(tmp)) {
405 			SetPageReserved(page);
406 			continue;
407 		}
408 		ClearPageReserved(page);
409 #ifdef CONFIG_LIMITED_DMA
410 		set_page_address(page, lowmem_page_address(page));
411 #endif
412 		init_page_count(page);
413 		__free_page(page);
414 		totalhigh_pages++;
415 	}
416 	totalram_pages += totalhigh_pages;
417 	num_physpages += totalhigh_pages;
418 #endif
419 
420 	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
421 	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
422 	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
423 
424 #ifdef CONFIG_64BIT
425 	if ((unsigned long) &_text > (unsigned long) CKSEG0)
426 		/* The -4 is a hack so that user tools don't have to handle
427 		   the overflow.  */
428 		kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4);
429 #endif
430 	kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
431 	kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
432 		   VMALLOC_END-VMALLOC_START);
433 
434 	printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
435 	       "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
436 	       (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
437 	       ram << (PAGE_SHIFT-10),
438 	       codesize >> 10,
439 	       reservedpages << (PAGE_SHIFT-10),
440 	       datasize >> 10,
441 	       initsize >> 10,
442 	       (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
443 }
444 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
445 
446 static void free_init_pages(char *what, unsigned long begin, unsigned long end)
447 {
448 	unsigned long pfn;
449 
450 	for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
451 		struct page *page = pfn_to_page(pfn);
452 		void *addr = phys_to_virt(PFN_PHYS(pfn));
453 
454 		ClearPageReserved(page);
455 		init_page_count(page);
456 		memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
457 		__free_page(page);
458 		totalram_pages++;
459 	}
460 	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
461 }
462 
463 #ifdef CONFIG_BLK_DEV_INITRD
464 void free_initrd_mem(unsigned long start, unsigned long end)
465 {
466 	free_init_pages("initrd memory",
467 			virt_to_phys((void *)start),
468 			virt_to_phys((void *)end));
469 }
470 #endif
471 
472 extern unsigned long prom_free_prom_memory(void);
473 
474 void free_initmem(void)
475 {
476 	unsigned long freed;
477 
478 	freed = prom_free_prom_memory();
479 	if (freed)
480 		printk(KERN_INFO "Freeing firmware memory: %ldk freed\n",freed);
481 
482 	free_init_pages("unused kernel memory",
483 			__pa_symbol(&__init_begin),
484 			__pa_symbol(&__init_end));
485 }
486