ca217327e8d27bb41c7fe1dac29be90e65919d41
[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 unsigned long *sparc_valid_addr_bitmap;
41 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
42
43 unsigned long phys_base;
44 EXPORT_SYMBOL(phys_base);
45
46 unsigned long pfn_base;
47 EXPORT_SYMBOL(pfn_base);
48
49 unsigned long page_kernel;
50 EXPORT_SYMBOL(page_kernel);
51
52 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
53 unsigned long sparc_unmapped_base;
54
55 struct pgtable_cache_struct pgt_quicklists;
56
57 /* Initial ramdisk setup */
58 extern unsigned int sparc_ramdisk_image;
59 extern unsigned int sparc_ramdisk_size;
60
61 unsigned long highstart_pfn, highend_pfn;
62
63 pte_t *kmap_pte;
64 pgprot_t kmap_prot;
65
66 #define kmap_get_fixmap_pte(vaddr) \
67         pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
68
69 void __init kmap_init(void)
70 {
71         /* cache the first kmap pte */
72         kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
73         kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
74 }
75
76 void show_mem(unsigned int filter)
77 {
78         printk("Mem-info:\n");
79         show_free_areas(filter);
80         printk("Free swap:       %6ldkB\n",
81                nr_swap_pages << (PAGE_SHIFT-10));
82         printk("%ld pages of RAM\n", totalram_pages);
83         printk("%ld free pages\n", nr_free_pages());
84 #if 0 /* undefined pgtable_cache_size, pgd_cache_size */
85         printk("%ld pages in page table cache\n",pgtable_cache_size);
86 #ifndef CONFIG_SMP
87         if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
88                 printk("%ld entries in page dir cache\n",pgd_cache_size);
89 #endif  
90 #endif
91 }
92
93 void __init sparc_context_init(int numctx)
94 {
95         int ctx;
96
97         ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
98
99         for(ctx = 0; ctx < numctx; ctx++) {
100                 struct ctx_list *clist;
101
102                 clist = (ctx_list_pool + ctx);
103                 clist->ctx_number = ctx;
104                 clist->ctx_mm = NULL;
105         }
106         ctx_free.next = ctx_free.prev = &ctx_free;
107         ctx_used.next = ctx_used.prev = &ctx_used;
108         for(ctx = 0; ctx < numctx; ctx++)
109                 add_to_free_ctxlist(ctx_list_pool + ctx);
110 }
111
112 extern unsigned long cmdline_memory_size;
113 unsigned long last_valid_pfn;
114
115 unsigned long calc_highpages(void)
116 {
117         int i;
118         int nr = 0;
119
120         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
121                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
122                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
123
124                 if (end_pfn <= max_low_pfn)
125                         continue;
126
127                 if (start_pfn < max_low_pfn)
128                         start_pfn = max_low_pfn;
129
130                 nr += end_pfn - start_pfn;
131         }
132
133         return nr;
134 }
135
136 static unsigned long calc_max_low_pfn(void)
137 {
138         int i;
139         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
140         unsigned long curr_pfn, last_pfn;
141
142         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
143         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
144                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
145
146                 if (curr_pfn >= tmp) {
147                         if (last_pfn < tmp)
148                                 tmp = last_pfn;
149                         break;
150                 }
151
152                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
153         }
154
155         return tmp;
156 }
157
158 unsigned long __init bootmem_init(unsigned long *pages_avail)
159 {
160         unsigned long bootmap_size, start_pfn;
161         unsigned long end_of_phys_memory = 0UL;
162         unsigned long bootmap_pfn, bytes_avail, size;
163         int i;
164
165         bytes_avail = 0UL;
166         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
167                 end_of_phys_memory = sp_banks[i].base_addr +
168                         sp_banks[i].num_bytes;
169                 bytes_avail += sp_banks[i].num_bytes;
170                 if (cmdline_memory_size) {
171                         if (bytes_avail > cmdline_memory_size) {
172                                 unsigned long slack = bytes_avail - cmdline_memory_size;
173
174                                 bytes_avail -= slack;
175                                 end_of_phys_memory -= slack;
176
177                                 sp_banks[i].num_bytes -= slack;
178                                 if (sp_banks[i].num_bytes == 0) {
179                                         sp_banks[i].base_addr = 0xdeadbeef;
180                                 } else {
181                                         sp_banks[i+1].num_bytes = 0;
182                                         sp_banks[i+1].base_addr = 0xdeadbeef;
183                                 }
184                                 break;
185                         }
186                 }
187         }
188
189         /* Start with page aligned address of last symbol in kernel
190          * image.  
191          */
192         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
193
194         /* Now shift down to get the real physical page frame number. */
195         start_pfn >>= PAGE_SHIFT;
196
197         bootmap_pfn = start_pfn;
198
199         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
200
201         max_low_pfn = max_pfn;
202         highstart_pfn = highend_pfn = max_pfn;
203
204         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
205                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
206                 max_low_pfn = calc_max_low_pfn();
207                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
208                     calc_highpages() >> (20 - PAGE_SHIFT));
209         }
210
211 #ifdef CONFIG_BLK_DEV_INITRD
212         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
213         if (sparc_ramdisk_image) {
214                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
215                         sparc_ramdisk_image -= KERNBASE;
216                 initrd_start = sparc_ramdisk_image + phys_base;
217                 initrd_end = initrd_start + sparc_ramdisk_size;
218                 if (initrd_end > end_of_phys_memory) {
219                         printk(KERN_CRIT "initrd extends beyond end of memory "
220                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
221                                initrd_end, end_of_phys_memory);
222                         initrd_start = 0;
223                 }
224                 if (initrd_start) {
225                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
226                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
227                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
228                 }
229         }
230 #endif  
231         /* Initialize the boot-time allocator. */
232         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
233                                          max_low_pfn);
234
235         /* Now register the available physical memory with the
236          * allocator.
237          */
238         *pages_avail = 0;
239         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
240                 unsigned long curr_pfn, last_pfn;
241
242                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
243                 if (curr_pfn >= max_low_pfn)
244                         break;
245
246                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
247                 if (last_pfn > max_low_pfn)
248                         last_pfn = max_low_pfn;
249
250                 /*
251                  * .. finally, did all the rounding and playing
252                  * around just make the area go away?
253                  */
254                 if (last_pfn <= curr_pfn)
255                         continue;
256
257                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
258                 *pages_avail += last_pfn - curr_pfn;
259
260                 free_bootmem(sp_banks[i].base_addr, size);
261         }
262
263 #ifdef CONFIG_BLK_DEV_INITRD
264         if (initrd_start) {
265                 /* Reserve the initrd image area. */
266                 size = initrd_end - initrd_start;
267                 reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
268                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
269
270                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
271                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;            
272         }
273 #endif
274         /* Reserve the kernel text/data/bss. */
275         size = (start_pfn << PAGE_SHIFT) - phys_base;
276         reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
277         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
278
279         /* Reserve the bootmem map.   We do not account for it
280          * in pages_avail because we will release that memory
281          * in free_all_bootmem.
282          */
283         size = bootmap_size;
284         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
285         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
286
287         return max_pfn;
288 }
289
290 /*
291  * check_pgt_cache
292  *
293  * This is called at the end of unmapping of VMA (zap_page_range),
294  * to rescan the page cache for architecture specific things,
295  * presumably something like sun4/sun4c PMEGs. Most architectures
296  * define check_pgt_cache empty.
297  *
298  * We simply copy the 2.4 implementation for now.
299  */
300 static int pgt_cache_water[2] = { 25, 50 };
301
302 void check_pgt_cache(void)
303 {
304         do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
305 }
306
307 /*
308  * paging_init() sets up the page tables: We call the MMU specific
309  * init routine based upon the Sun model type on the Sparc.
310  *
311  */
312 extern void sun4c_paging_init(void);
313 extern void srmmu_paging_init(void);
314 extern void device_scan(void);
315
316 pgprot_t PAGE_SHARED __read_mostly;
317 EXPORT_SYMBOL(PAGE_SHARED);
318
319 void __init paging_init(void)
320 {
321         switch(sparc_cpu_model) {
322         case sun4c:
323         case sun4e:
324         case sun4:
325                 sun4c_paging_init();
326                 sparc_unmapped_base = 0xe0000000;
327                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
328                 break;
329         case sparc_leon:
330                 leon_init();
331                 /* fall through */
332         case sun4m:
333         case sun4d:
334                 srmmu_paging_init();
335                 sparc_unmapped_base = 0x50000000;
336                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
337                 break;
338         default:
339                 prom_printf("paging_init: Cannot init paging on this Sparc\n");
340                 prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
341                 prom_printf("paging_init: Halting...\n");
342                 prom_halt();
343         };
344
345         /* Initialize the protection map with non-constant, MMU dependent values. */
346         protection_map[0] = PAGE_NONE;
347         protection_map[1] = PAGE_READONLY;
348         protection_map[2] = PAGE_COPY;
349         protection_map[3] = PAGE_COPY;
350         protection_map[4] = PAGE_READONLY;
351         protection_map[5] = PAGE_READONLY;
352         protection_map[6] = PAGE_COPY;
353         protection_map[7] = PAGE_COPY;
354         protection_map[8] = PAGE_NONE;
355         protection_map[9] = PAGE_READONLY;
356         protection_map[10] = PAGE_SHARED;
357         protection_map[11] = PAGE_SHARED;
358         protection_map[12] = PAGE_READONLY;
359         protection_map[13] = PAGE_READONLY;
360         protection_map[14] = PAGE_SHARED;
361         protection_map[15] = PAGE_SHARED;
362         btfixup();
363         prom_build_devicetree();
364         of_fill_in_cpu_data();
365         device_scan();
366 }
367
368 static void __init taint_real_pages(void)
369 {
370         int i;
371
372         for (i = 0; sp_banks[i].num_bytes; i++) {
373                 unsigned long start, end;
374
375                 start = sp_banks[i].base_addr;
376                 end = start + sp_banks[i].num_bytes;
377
378                 while (start < end) {
379                         set_bit(start >> 20, sparc_valid_addr_bitmap);
380                         start += PAGE_SIZE;
381                 }
382         }
383 }
384
385 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
386 {
387         unsigned long tmp;
388
389 #ifdef CONFIG_DEBUG_HIGHMEM
390         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
391 #endif
392
393         for (tmp = start_pfn; tmp < end_pfn; tmp++) {
394                 struct page *page = pfn_to_page(tmp);
395
396                 ClearPageReserved(page);
397                 init_page_count(page);
398                 __free_page(page);
399                 totalhigh_pages++;
400         }
401 }
402
403 void __init mem_init(void)
404 {
405         int codepages = 0;
406         int datapages = 0;
407         int initpages = 0; 
408         int reservedpages = 0;
409         int i;
410
411         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
412                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
413                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
414                        PKMAP_BASE,
415                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
416                        FIXADDR_START);
417                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
418                 prom_halt();
419         }
420
421
422         /* Saves us work later. */
423         memset((void *)&empty_zero_page, 0, PAGE_SIZE);
424
425         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
426         i += 1;
427         sparc_valid_addr_bitmap = (unsigned long *)
428                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
429
430         if (sparc_valid_addr_bitmap == NULL) {
431                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
432                 prom_halt();
433         }
434         memset(sparc_valid_addr_bitmap, 0, i << 2);
435
436         taint_real_pages();
437
438         max_mapnr = last_valid_pfn - pfn_base;
439         high_memory = __va(max_low_pfn << PAGE_SHIFT);
440
441         totalram_pages = free_all_bootmem();
442
443         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
444                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
445                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
446
447                 num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
448
449                 if (end_pfn <= highstart_pfn)
450                         continue;
451
452                 if (start_pfn < highstart_pfn)
453                         start_pfn = highstart_pfn;
454
455                 map_high_region(start_pfn, end_pfn);
456         }
457         
458         totalram_pages += totalhigh_pages;
459
460         codepages = (((unsigned long) &_etext) - ((unsigned long)&_start));
461         codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
462         datapages = (((unsigned long) &_edata) - ((unsigned long)&_etext));
463         datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
464         initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
465         initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
466
467         /* Ignore memory holes for the purpose of counting reserved pages */
468         for (i=0; i < max_low_pfn; i++)
469                 if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
470                     && PageReserved(pfn_to_page(i)))
471                         reservedpages++;
472
473         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
474                nr_free_pages() << (PAGE_SHIFT-10),
475                num_physpages << (PAGE_SHIFT - 10),
476                codepages << (PAGE_SHIFT-10),
477                reservedpages << (PAGE_SHIFT - 10),
478                datapages << (PAGE_SHIFT-10), 
479                initpages << (PAGE_SHIFT-10),
480                totalhigh_pages << (PAGE_SHIFT-10));
481 }
482
483 void free_initmem (void)
484 {
485         unsigned long addr;
486         unsigned long freed;
487
488         addr = (unsigned long)(&__init_begin);
489         freed = (unsigned long)(&__init_end) - addr;
490         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
491                 struct page *p;
492
493                 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
494                 p = virt_to_page(addr);
495
496                 ClearPageReserved(p);
497                 init_page_count(p);
498                 __free_page(p);
499                 totalram_pages++;
500                 num_physpages++;
501         }
502         printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
503                 freed >> 10);
504 }
505
506 #ifdef CONFIG_BLK_DEV_INITRD
507 void free_initrd_mem(unsigned long start, unsigned long end)
508 {
509         if (start < end)
510                 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
511                         (end - start) >> 10);
512         for (; start < end; start += PAGE_SIZE) {
513                 struct page *p;
514
515                 memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
516                 p = virt_to_page(start);
517
518                 ClearPageReserved(p);
519                 init_page_count(p);
520                 __free_page(p);
521                 totalram_pages++;
522                 num_physpages++;
523         }
524 }
525 #endif
526
527 void sparc_flush_page_to_ram(struct page *page)
528 {
529         unsigned long vaddr = (unsigned long)page_address(page);
530
531         if (vaddr)
532                 __flush_page_to_ram(vaddr);
533 }
534 EXPORT_SYMBOL(sparc_flush_page_to_ram);