6d0e02c4fe09cdc318d6da849668495546d21897
[linux-2.6.git] / arch / sparc / mm / init_32.c
1 /*
2  *  linux/arch/sparc/mm/init.c
3  *
4  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5  *  Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
6  *  Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
7  *  Copyright (C) 2000 Anton Blanchard (anton@samba.org)
8  */
9
10 #include <linux/module.h>
11 #include <linux/signal.h>
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/string.h>
16 #include <linux/types.h>
17 #include <linux/ptrace.h>
18 #include <linux/mman.h>
19 #include <linux/mm.h>
20 #include <linux/swap.h>
21 #include <linux/initrd.h>
22 #include <linux/init.h>
23 #include <linux/highmem.h>
24 #include <linux/bootmem.h>
25 #include <linux/pagemap.h>
26 #include <linux/poison.h>
27 #include <linux/gfp.h>
28
29 #include <asm/sections.h>
30 #include <asm/system.h>
31 #include <asm/vac-ops.h>
32 #include <asm/page.h>
33 #include <asm/pgtable.h>
34 #include <asm/vaddrs.h>
35 #include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
36 #include <asm/tlb.h>
37 #include <asm/prom.h>
38 #include <asm/leon.h>
39
40 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
41
42 unsigned long *sparc_valid_addr_bitmap;
43 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
44
45 unsigned long phys_base;
46 EXPORT_SYMBOL(phys_base);
47
48 unsigned long pfn_base;
49 EXPORT_SYMBOL(pfn_base);
50
51 unsigned long page_kernel;
52 EXPORT_SYMBOL(page_kernel);
53
54 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
55 unsigned long sparc_unmapped_base;
56
57 struct pgtable_cache_struct pgt_quicklists;
58
59 /* Initial ramdisk setup */
60 extern unsigned int sparc_ramdisk_image;
61 extern unsigned int sparc_ramdisk_size;
62
63 unsigned long highstart_pfn, highend_pfn;
64
65 pte_t *kmap_pte;
66 pgprot_t kmap_prot;
67
68 #define kmap_get_fixmap_pte(vaddr) \
69         pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
70
71 void __init kmap_init(void)
72 {
73         /* cache the first kmap pte */
74         kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
75         kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
76 }
77
78 void show_mem(void)
79 {
80         printk("Mem-info:\n");
81         show_free_areas();
82         printk("Free swap:       %6ldkB\n",
83                nr_swap_pages << (PAGE_SHIFT-10));
84         printk("%ld pages of RAM\n", totalram_pages);
85         printk("%ld free pages\n", nr_free_pages());
86 #if 0 /* undefined pgtable_cache_size, pgd_cache_size */
87         printk("%ld pages in page table cache\n",pgtable_cache_size);
88 #ifndef CONFIG_SMP
89         if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
90                 printk("%ld entries in page dir cache\n",pgd_cache_size);
91 #endif  
92 #endif
93 }
94
95 void __init sparc_context_init(int numctx)
96 {
97         int ctx;
98
99         ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
100
101         for(ctx = 0; ctx < numctx; ctx++) {
102                 struct ctx_list *clist;
103
104                 clist = (ctx_list_pool + ctx);
105                 clist->ctx_number = ctx;
106                 clist->ctx_mm = NULL;
107         }
108         ctx_free.next = ctx_free.prev = &ctx_free;
109         ctx_used.next = ctx_used.prev = &ctx_used;
110         for(ctx = 0; ctx < numctx; ctx++)
111                 add_to_free_ctxlist(ctx_list_pool + ctx);
112 }
113
114 extern unsigned long cmdline_memory_size;
115 unsigned long last_valid_pfn;
116
117 unsigned long calc_highpages(void)
118 {
119         int i;
120         int nr = 0;
121
122         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
123                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
124                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
125
126                 if (end_pfn <= max_low_pfn)
127                         continue;
128
129                 if (start_pfn < max_low_pfn)
130                         start_pfn = max_low_pfn;
131
132                 nr += end_pfn - start_pfn;
133         }
134
135         return nr;
136 }
137
138 static unsigned long calc_max_low_pfn(void)
139 {
140         int i;
141         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
142         unsigned long curr_pfn, last_pfn;
143
144         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
145         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
146                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
147
148                 if (curr_pfn >= tmp) {
149                         if (last_pfn < tmp)
150                                 tmp = last_pfn;
151                         break;
152                 }
153
154                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
155         }
156
157         return tmp;
158 }
159
160 unsigned long __init bootmem_init(unsigned long *pages_avail)
161 {
162         unsigned long bootmap_size, start_pfn;
163         unsigned long end_of_phys_memory = 0UL;
164         unsigned long bootmap_pfn, bytes_avail, size;
165         int i;
166
167         bytes_avail = 0UL;
168         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
169                 end_of_phys_memory = sp_banks[i].base_addr +
170                         sp_banks[i].num_bytes;
171                 bytes_avail += sp_banks[i].num_bytes;
172                 if (cmdline_memory_size) {
173                         if (bytes_avail > cmdline_memory_size) {
174                                 unsigned long slack = bytes_avail - cmdline_memory_size;
175
176                                 bytes_avail -= slack;
177                                 end_of_phys_memory -= slack;
178
179                                 sp_banks[i].num_bytes -= slack;
180                                 if (sp_banks[i].num_bytes == 0) {
181                                         sp_banks[i].base_addr = 0xdeadbeef;
182                                 } else {
183                                         sp_banks[i+1].num_bytes = 0;
184                                         sp_banks[i+1].base_addr = 0xdeadbeef;
185                                 }
186                                 break;
187                         }
188                 }
189         }
190
191         /* Start with page aligned address of last symbol in kernel
192          * image.  
193          */
194         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
195
196         /* Now shift down to get the real physical page frame number. */
197         start_pfn >>= PAGE_SHIFT;
198
199         bootmap_pfn = start_pfn;
200
201         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
202
203         max_low_pfn = max_pfn;
204         highstart_pfn = highend_pfn = max_pfn;
205
206         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
207                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
208                 max_low_pfn = calc_max_low_pfn();
209                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
210                     calc_highpages() >> (20 - PAGE_SHIFT));
211         }
212
213 #ifdef CONFIG_BLK_DEV_INITRD
214         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
215         if (sparc_ramdisk_image) {
216                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
217                         sparc_ramdisk_image -= KERNBASE;
218                 initrd_start = sparc_ramdisk_image + phys_base;
219                 initrd_end = initrd_start + sparc_ramdisk_size;
220                 if (initrd_end > end_of_phys_memory) {
221                         printk(KERN_CRIT "initrd extends beyond end of memory "
222                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
223                                initrd_end, end_of_phys_memory);
224                         initrd_start = 0;
225                 }
226                 if (initrd_start) {
227                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
228                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
229                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
230                 }
231         }
232 #endif  
233         /* Initialize the boot-time allocator. */
234         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
235                                          max_low_pfn);
236
237         /* Now register the available physical memory with the
238          * allocator.
239          */
240         *pages_avail = 0;
241         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
242                 unsigned long curr_pfn, last_pfn;
243
244                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
245                 if (curr_pfn >= max_low_pfn)
246                         break;
247
248                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
249                 if (last_pfn > max_low_pfn)
250                         last_pfn = max_low_pfn;
251
252                 /*
253                  * .. finally, did all the rounding and playing
254                  * around just make the area go away?
255                  */
256                 if (last_pfn <= curr_pfn)
257                         continue;
258
259                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
260                 *pages_avail += last_pfn - curr_pfn;
261
262                 free_bootmem(sp_banks[i].base_addr, size);
263         }
264
265 #ifdef CONFIG_BLK_DEV_INITRD
266         if (initrd_start) {
267                 /* Reserve the initrd image area. */
268                 size = initrd_end - initrd_start;
269                 reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
270                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
271
272                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
273                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;            
274         }
275 #endif
276         /* Reserve the kernel text/data/bss. */
277         size = (start_pfn << PAGE_SHIFT) - phys_base;
278         reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
279         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
280
281         /* Reserve the bootmem map.   We do not account for it
282          * in pages_avail because we will release that memory
283          * in free_all_bootmem.
284          */
285         size = bootmap_size;
286         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
287         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
288
289         return max_pfn;
290 }
291
292 /*
293  * check_pgt_cache
294  *
295  * This is called at the end of unmapping of VMA (zap_page_range),
296  * to rescan the page cache for architecture specific things,
297  * presumably something like sun4/sun4c PMEGs. Most architectures
298  * define check_pgt_cache empty.
299  *
300  * We simply copy the 2.4 implementation for now.
301  */
302 static int pgt_cache_water[2] = { 25, 50 };
303
304 void check_pgt_cache(void)
305 {
306         do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
307 }
308
309 /*
310  * paging_init() sets up the page tables: We call the MMU specific
311  * init routine based upon the Sun model type on the Sparc.
312  *
313  */
314 extern void sun4c_paging_init(void);
315 extern void srmmu_paging_init(void);
316 extern void device_scan(void);
317
318 pgprot_t PAGE_SHARED __read_mostly;
319 EXPORT_SYMBOL(PAGE_SHARED);
320
321 void __init paging_init(void)
322 {
323         switch(sparc_cpu_model) {
324         case sun4c:
325         case sun4e:
326         case sun4:
327                 sun4c_paging_init();
328                 sparc_unmapped_base = 0xe0000000;
329                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
330                 break;
331         case sparc_leon:
332                 leon_init();
333                 /* fall through */
334         case sun4m:
335         case sun4d:
336                 srmmu_paging_init();
337                 sparc_unmapped_base = 0x50000000;
338                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
339                 break;
340         default:
341                 prom_printf("paging_init: Cannot init paging on this Sparc\n");
342                 prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
343                 prom_printf("paging_init: Halting...\n");
344                 prom_halt();
345         };
346
347         /* Initialize the protection map with non-constant, MMU dependent values. */
348         protection_map[0] = PAGE_NONE;
349         protection_map[1] = PAGE_READONLY;
350         protection_map[2] = PAGE_COPY;
351         protection_map[3] = PAGE_COPY;
352         protection_map[4] = PAGE_READONLY;
353         protection_map[5] = PAGE_READONLY;
354         protection_map[6] = PAGE_COPY;
355         protection_map[7] = PAGE_COPY;
356         protection_map[8] = PAGE_NONE;
357         protection_map[9] = PAGE_READONLY;
358         protection_map[10] = PAGE_SHARED;
359         protection_map[11] = PAGE_SHARED;
360         protection_map[12] = PAGE_READONLY;
361         protection_map[13] = PAGE_READONLY;
362         protection_map[14] = PAGE_SHARED;
363         protection_map[15] = PAGE_SHARED;
364         btfixup();
365         prom_build_devicetree();
366         of_fill_in_cpu_data();
367         device_scan();
368 }
369
370 static void __init taint_real_pages(void)
371 {
372         int i;
373
374         for (i = 0; sp_banks[i].num_bytes; i++) {
375                 unsigned long start, end;
376
377                 start = sp_banks[i].base_addr;
378                 end = start + sp_banks[i].num_bytes;
379
380                 while (start < end) {
381                         set_bit(start >> 20, sparc_valid_addr_bitmap);
382                         start += PAGE_SIZE;
383                 }
384         }
385 }
386
387 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
388 {
389         unsigned long tmp;
390
391 #ifdef CONFIG_DEBUG_HIGHMEM
392         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
393 #endif
394
395         for (tmp = start_pfn; tmp < end_pfn; tmp++) {
396                 struct page *page = pfn_to_page(tmp);
397
398                 ClearPageReserved(page);
399                 init_page_count(page);
400                 __free_page(page);
401                 totalhigh_pages++;
402         }
403 }
404
405 void __init mem_init(void)
406 {
407         int codepages = 0;
408         int datapages = 0;
409         int initpages = 0; 
410         int reservedpages = 0;
411         int i;
412
413         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
414                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
415                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
416                        PKMAP_BASE,
417                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
418                        FIXADDR_START);
419                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
420                 prom_halt();
421         }
422
423
424         /* Saves us work later. */
425         memset((void *)&empty_zero_page, 0, PAGE_SIZE);
426
427         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
428         i += 1;
429         sparc_valid_addr_bitmap = (unsigned long *)
430                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
431
432         if (sparc_valid_addr_bitmap == NULL) {
433                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
434                 prom_halt();
435         }
436         memset(sparc_valid_addr_bitmap, 0, i << 2);
437
438         taint_real_pages();
439
440         max_mapnr = last_valid_pfn - pfn_base;
441         high_memory = __va(max_low_pfn << PAGE_SHIFT);
442
443         totalram_pages = free_all_bootmem();
444
445         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
446                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
447                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
448
449                 num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
450
451                 if (end_pfn <= highstart_pfn)
452                         continue;
453
454                 if (start_pfn < highstart_pfn)
455                         start_pfn = highstart_pfn;
456
457                 map_high_region(start_pfn, end_pfn);
458         }
459         
460         totalram_pages += totalhigh_pages;
461
462         codepages = (((unsigned long) &_etext) - ((unsigned long)&_start));
463         codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
464         datapages = (((unsigned long) &_edata) - ((unsigned long)&_etext));
465         datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
466         initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
467         initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
468
469         /* Ignore memory holes for the purpose of counting reserved pages */
470         for (i=0; i < max_low_pfn; i++)
471                 if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
472                     && PageReserved(pfn_to_page(i)))
473                         reservedpages++;
474
475         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
476                nr_free_pages() << (PAGE_SHIFT-10),
477                num_physpages << (PAGE_SHIFT - 10),
478                codepages << (PAGE_SHIFT-10),
479                reservedpages << (PAGE_SHIFT - 10),
480                datapages << (PAGE_SHIFT-10), 
481                initpages << (PAGE_SHIFT-10),
482                totalhigh_pages << (PAGE_SHIFT-10));
483 }
484
485 void free_initmem (void)
486 {
487         unsigned long addr;
488         unsigned long freed;
489
490         addr = (unsigned long)(&__init_begin);
491         freed = (unsigned long)(&__init_end) - addr;
492         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
493                 struct page *p;
494
495                 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
496                 p = virt_to_page(addr);
497
498                 ClearPageReserved(p);
499                 init_page_count(p);
500                 __free_page(p);
501                 totalram_pages++;
502                 num_physpages++;
503         }
504         printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
505                 freed >> 10);
506 }
507
508 #ifdef CONFIG_BLK_DEV_INITRD
509 void free_initrd_mem(unsigned long start, unsigned long end)
510 {
511         if (start < end)
512                 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
513                         (end - start) >> 10);
514         for (; start < end; start += PAGE_SIZE) {
515                 struct page *p;
516
517                 memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
518                 p = virt_to_page(start);
519
520                 ClearPageReserved(p);
521                 init_page_count(p);
522                 __free_page(p);
523                 totalram_pages++;
524                 num_physpages++;
525         }
526 }
527 #endif
528
529 void sparc_flush_page_to_ram(struct page *page)
530 {
531         unsigned long vaddr = (unsigned long)page_address(page);
532
533         if (vaddr)
534                 __flush_page_to_ram(vaddr);
535 }
536 EXPORT_SYMBOL(sparc_flush_page_to_ram);