Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/linville...
[kernel.git] / arch / mips / mm / init.c
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/bug.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/signal.h>
15 #include <linux/sched.h>
16 #include <linux/smp.h>
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/string.h>
20 #include <linux/types.h>
21 #include <linux/pagemap.h>
22 #include <linux/ptrace.h>
23 #include <linux/mman.h>
24 #include <linux/mm.h>
25 #include <linux/bootmem.h>
26 #include <linux/highmem.h>
27 #include <linux/swap.h>
28 #include <linux/proc_fs.h>
29 #include <linux/pfn.h>
30 #include <linux/hardirq.h>
31
32 #include <asm/asm-offsets.h>
33 #include <asm/bootinfo.h>
34 #include <asm/cachectl.h>
35 #include <asm/cpu.h>
36 #include <asm/dma.h>
37 #include <asm/kmap_types.h>
38 #include <asm/mmu_context.h>
39 #include <asm/sections.h>
40 #include <asm/pgtable.h>
41 #include <asm/pgalloc.h>
42 #include <asm/tlb.h>
43 #include <asm/fixmap.h>
44
45 /* Atomicity and interruptability */
46 #ifdef CONFIG_MIPS_MT_SMTC
47
48 #include <asm/mipsmtregs.h>
49
50 #define ENTER_CRITICAL(flags) \
51         { \
52         unsigned int mvpflags; \
53         local_irq_save(flags);\
54         mvpflags = dvpe()
55 #define EXIT_CRITICAL(flags) \
56         evpe(mvpflags); \
57         local_irq_restore(flags); \
58         }
59 #else
60
61 #define ENTER_CRITICAL(flags) local_irq_save(flags)
62 #define EXIT_CRITICAL(flags) local_irq_restore(flags)
63
64 #endif /* CONFIG_MIPS_MT_SMTC */
65
66 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
67
68 /*
69  * We have up to 8 empty zeroed pages so we can map one of the right colour
70  * when needed.  This is necessary only on R4000 / R4400 SC and MC versions
71  * where we have to avoid VCED / VECI exceptions for good performance at
72  * any price.  Since page is never written to after the initialization we
73  * don't have to care about aliases on other CPUs.
74  */
75 unsigned long empty_zero_page, zero_page_mask;
76 EXPORT_SYMBOL_GPL(empty_zero_page);
77
78 /*
79  * Not static inline because used by IP27 special magic initialization code
80  */
81 unsigned long setup_zero_pages(void)
82 {
83         unsigned int order;
84         unsigned long size;
85         struct page *page;
86
87         if (cpu_has_vce)
88                 order = 3;
89         else
90                 order = 0;
91
92         empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
93         if (!empty_zero_page)
94                 panic("Oh boy, that early out of memory?");
95
96         page = virt_to_page((void *)empty_zero_page);
97         split_page(page, order);
98         while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) {
99                 SetPageReserved(page);
100                 page++;
101         }
102
103         size = PAGE_SIZE << order;
104         zero_page_mask = (size - 1) & PAGE_MASK;
105
106         return 1UL << order;
107 }
108
109 #ifdef CONFIG_MIPS_MT_SMTC
110 static pte_t *kmap_coherent_pte;
111 static void __init kmap_coherent_init(void)
112 {
113         unsigned long vaddr;
114
115         /* cache the first coherent kmap pte */
116         vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
117         kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
118 }
119 #else
120 static inline void kmap_coherent_init(void) {}
121 #endif
122
123 void *kmap_coherent(struct page *page, unsigned long addr)
124 {
125         enum fixed_addresses idx;
126         unsigned long vaddr, flags, entrylo;
127         unsigned long old_ctx;
128         pte_t pte;
129         int tlbidx;
130
131         BUG_ON(Page_dcache_dirty(page));
132
133         inc_preempt_count();
134         idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
135 #ifdef CONFIG_MIPS_MT_SMTC
136         idx += FIX_N_COLOURS * smp_processor_id() +
137                 (in_interrupt() ? (FIX_N_COLOURS * NR_CPUS) : 0);
138 #else
139         idx += in_interrupt() ? FIX_N_COLOURS : 0;
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)
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 void kunmap_coherent(void)
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             page_mapped(from) && !Page_dcache_dirty(from)) {
214                 vfrom = kmap_coherent(from, vaddr);
215                 copy_page(vto, vfrom);
216                 kunmap_coherent();
217         } else {
218                 vfrom = kmap_atomic(from, KM_USER0);
219                 copy_page(vto, vfrom);
220                 kunmap_atomic(vfrom, KM_USER0);
221         }
222         if ((!cpu_has_ic_fills_f_dc) ||
223             pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
224                 flush_data_cache_page((unsigned long)vto);
225         kunmap_atomic(vto, KM_USER1);
226         /* Make sure this page is cleared on other CPU's too before using it */
227         smp_wmb();
228 }
229
230 void copy_to_user_page(struct vm_area_struct *vma,
231         struct page *page, unsigned long vaddr, void *dst, const void *src,
232         unsigned long len)
233 {
234         if (cpu_has_dc_aliases &&
235             page_mapped(page) && !Page_dcache_dirty(page)) {
236                 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
237                 memcpy(vto, src, len);
238                 kunmap_coherent();
239         } else {
240                 memcpy(dst, src, len);
241                 if (cpu_has_dc_aliases)
242                         SetPageDcacheDirty(page);
243         }
244         if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
245                 flush_cache_page(vma, vaddr, page_to_pfn(page));
246 }
247
248 void copy_from_user_page(struct vm_area_struct *vma,
249         struct page *page, unsigned long vaddr, void *dst, const void *src,
250         unsigned long len)
251 {
252         if (cpu_has_dc_aliases &&
253             page_mapped(page) && !Page_dcache_dirty(page)) {
254                 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
255                 memcpy(dst, vfrom, len);
256                 kunmap_coherent();
257         } else {
258                 memcpy(dst, src, len);
259                 if (cpu_has_dc_aliases)
260                         SetPageDcacheDirty(page);
261         }
262 }
263
264 void __init fixrange_init(unsigned long start, unsigned long end,
265         pgd_t *pgd_base)
266 {
267 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC)
268         pgd_t *pgd;
269         pud_t *pud;
270         pmd_t *pmd;
271         pte_t *pte;
272         int i, j, k;
273         unsigned long vaddr;
274
275         vaddr = start;
276         i = __pgd_offset(vaddr);
277         j = __pud_offset(vaddr);
278         k = __pmd_offset(vaddr);
279         pgd = pgd_base + i;
280
281         for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
282                 pud = (pud_t *)pgd;
283                 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
284                         pmd = (pmd_t *)pud;
285                         for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
286                                 if (pmd_none(*pmd)) {
287                                         pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
288                                         set_pmd(pmd, __pmd((unsigned long)pte));
289                                         BUG_ON(pte != pte_offset_kernel(pmd, 0));
290                                 }
291                                 vaddr += PMD_SIZE;
292                         }
293                         k = 0;
294                 }
295                 j = 0;
296         }
297 #endif
298 }
299
300 #ifndef CONFIG_NEED_MULTIPLE_NODES
301 static int __init page_is_ram(unsigned long pagenr)
302 {
303         int i;
304
305         for (i = 0; i < boot_mem_map.nr_map; i++) {
306                 unsigned long addr, end;
307
308                 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
309                         /* not usable memory */
310                         continue;
311
312                 addr = PFN_UP(boot_mem_map.map[i].addr);
313                 end = PFN_DOWN(boot_mem_map.map[i].addr +
314                                boot_mem_map.map[i].size);
315
316                 if (pagenr >= addr && pagenr < end)
317                         return 1;
318         }
319
320         return 0;
321 }
322
323 void __init paging_init(void)
324 {
325         unsigned long max_zone_pfns[MAX_NR_ZONES];
326         unsigned long lastpfn;
327
328         pagetable_init();
329
330 #ifdef CONFIG_HIGHMEM
331         kmap_init();
332 #endif
333         kmap_coherent_init();
334
335 #ifdef CONFIG_ZONE_DMA
336         max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
337 #endif
338 #ifdef CONFIG_ZONE_DMA32
339         max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
340 #endif
341         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
342         lastpfn = max_low_pfn;
343 #ifdef CONFIG_HIGHMEM
344         max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
345         lastpfn = highend_pfn;
346
347         if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
348                 printk(KERN_WARNING "This processor doesn't support highmem."
349                        " %ldk highmem ignored\n",
350                        (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
351                 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
352                 lastpfn = max_low_pfn;
353         }
354 #endif
355
356         free_area_init_nodes(max_zone_pfns);
357 }
358
359 #ifdef CONFIG_64BIT
360 static struct kcore_list kcore_kseg0;
361 #endif
362
363 void __init mem_init(void)
364 {
365         unsigned long codesize, reservedpages, datasize, initsize;
366         unsigned long tmp, ram;
367
368 #ifdef CONFIG_HIGHMEM
369 #ifdef CONFIG_DISCONTIGMEM
370 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
371 #endif
372         max_mapnr = highend_pfn;
373 #else
374         max_mapnr = max_low_pfn;
375 #endif
376         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
377
378         totalram_pages += free_all_bootmem();
379         totalram_pages -= setup_zero_pages();   /* Setup zeroed pages.  */
380
381         reservedpages = ram = 0;
382         for (tmp = 0; tmp < max_low_pfn; tmp++)
383                 if (page_is_ram(tmp)) {
384                         ram++;
385                         if (PageReserved(pfn_to_page(tmp)))
386                                 reservedpages++;
387                 }
388         num_physpages = ram;
389
390 #ifdef CONFIG_HIGHMEM
391         for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
392                 struct page *page = pfn_to_page(tmp);
393
394                 if (!page_is_ram(tmp)) {
395                         SetPageReserved(page);
396                         continue;
397                 }
398                 ClearPageReserved(page);
399                 init_page_count(page);
400                 __free_page(page);
401                 totalhigh_pages++;
402         }
403         totalram_pages += totalhigh_pages;
404         num_physpages += totalhigh_pages;
405 #endif
406
407         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
408         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
409         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
410
411 #ifdef CONFIG_64BIT
412         if ((unsigned long) &_text > (unsigned long) CKSEG0)
413                 /* The -4 is a hack so that user tools don't have to handle
414                    the overflow.  */
415                 kclist_add(&kcore_kseg0, (void *) CKSEG0,
416                                 0x80000000 - 4, KCORE_TEXT);
417 #endif
418
419         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
420                "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
421                nr_free_pages() << (PAGE_SHIFT-10),
422                ram << (PAGE_SHIFT-10),
423                codesize >> 10,
424                reservedpages << (PAGE_SHIFT-10),
425                datasize >> 10,
426                initsize >> 10,
427                totalhigh_pages << (PAGE_SHIFT-10));
428 }
429 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
430
431 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
432 {
433         unsigned long pfn;
434
435         for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
436                 struct page *page = pfn_to_page(pfn);
437                 void *addr = phys_to_virt(PFN_PHYS(pfn));
438
439                 ClearPageReserved(page);
440                 init_page_count(page);
441                 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
442                 __free_page(page);
443                 totalram_pages++;
444         }
445         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
446 }
447
448 #ifdef CONFIG_BLK_DEV_INITRD
449 void free_initrd_mem(unsigned long start, unsigned long end)
450 {
451         free_init_pages("initrd memory",
452                         virt_to_phys((void *)start),
453                         virt_to_phys((void *)end));
454 }
455 #endif
456
457 void __init_refok free_initmem(void)
458 {
459         prom_free_prom_memory();
460         free_init_pages("unused kernel memory",
461                         __pa_symbol(&__init_begin),
462                         __pa_symbol(&__init_end));
463 }
464
465 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
466 unsigned long pgd_current[NR_CPUS];
467 #endif
468 /*
469  * On 64-bit we've got three-level pagetables with a slightly
470  * different layout ...
471  */
472 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
473
474 /*
475  * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
476  * are constants.  So we use the variants from asm-offset.h until that gcc
477  * will officially be retired.
478  */
479 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __page_aligned(_PGD_ORDER);
480 #ifdef CONFIG_64BIT
481 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER);
482 #endif
483 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);