Merge git://oss.sgi.com:8090/oss/git/xfs-2.6
[linux-2.6] / arch / sparc / mm / init.c
1 /*  $Id: init.c,v 1.103 2001/11/19 19:03:08 davem Exp $
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/config.h>
11 #include <linux/module.h>
12 #include <linux/signal.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
20 #include <linux/mm.h>
21 #include <linux/swap.h>
22 #include <linux/initrd.h>
23 #include <linux/init.h>
24 #include <linux/highmem.h>
25 #include <linux/bootmem.h>
26
27 #include <asm/system.h>
28 #include <asm/vac-ops.h>
29 #include <asm/page.h>
30 #include <asm/pgtable.h>
31 #include <asm/vaddrs.h>
32 #include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
33 #include <asm/tlb.h>
34
35 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
36
37 unsigned long *sparc_valid_addr_bitmap;
38
39 unsigned long phys_base;
40 unsigned long pfn_base;
41
42 unsigned long page_kernel;
43
44 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
45 unsigned long sparc_unmapped_base;
46
47 struct pgtable_cache_struct pgt_quicklists;
48
49 /* References to section boundaries */
50 extern char __init_begin, __init_end, _start, _end, etext , edata;
51
52 /* Initial ramdisk setup */
53 extern unsigned int sparc_ramdisk_image;
54 extern unsigned int sparc_ramdisk_size;
55
56 unsigned long highstart_pfn, highend_pfn;
57
58 pte_t *kmap_pte;
59 pgprot_t kmap_prot;
60
61 #define kmap_get_fixmap_pte(vaddr) \
62         pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
63
64 void __init kmap_init(void)
65 {
66         /* cache the first kmap pte */
67         kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
68         kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
69 }
70
71 void show_mem(void)
72 {
73         printk("Mem-info:\n");
74         show_free_areas();
75         printk("Free swap:       %6ldkB\n",
76                nr_swap_pages << (PAGE_SHIFT-10));
77         printk("%ld pages of RAM\n", totalram_pages);
78         printk("%d free pages\n", nr_free_pages());
79 #if 0 /* undefined pgtable_cache_size, pgd_cache_size */
80         printk("%ld pages in page table cache\n",pgtable_cache_size);
81 #ifndef CONFIG_SMP
82         if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
83                 printk("%ld entries in page dir cache\n",pgd_cache_size);
84 #endif  
85 #endif
86 }
87
88 void __init sparc_context_init(int numctx)
89 {
90         int ctx;
91
92         ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
93
94         for(ctx = 0; ctx < numctx; ctx++) {
95                 struct ctx_list *clist;
96
97                 clist = (ctx_list_pool + ctx);
98                 clist->ctx_number = ctx;
99                 clist->ctx_mm = NULL;
100         }
101         ctx_free.next = ctx_free.prev = &ctx_free;
102         ctx_used.next = ctx_used.prev = &ctx_used;
103         for(ctx = 0; ctx < numctx; ctx++)
104                 add_to_free_ctxlist(ctx_list_pool + ctx);
105 }
106
107 extern unsigned long cmdline_memory_size;
108 unsigned long last_valid_pfn;
109
110 unsigned long calc_highpages(void)
111 {
112         int i;
113         int nr = 0;
114
115         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
116                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
117                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
118
119                 if (end_pfn <= max_low_pfn)
120                         continue;
121
122                 if (start_pfn < max_low_pfn)
123                         start_pfn = max_low_pfn;
124
125                 nr += end_pfn - start_pfn;
126         }
127
128         return nr;
129 }
130
131 unsigned long calc_max_low_pfn(void)
132 {
133         int i;
134         unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
135         unsigned long curr_pfn, last_pfn;
136
137         last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
138         for (i = 1; sp_banks[i].num_bytes != 0; i++) {
139                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
140
141                 if (curr_pfn >= tmp) {
142                         if (last_pfn < tmp)
143                                 tmp = last_pfn;
144                         break;
145                 }
146
147                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
148         }
149
150         return tmp;
151 }
152
153 unsigned long __init bootmem_init(unsigned long *pages_avail)
154 {
155         unsigned long bootmap_size, start_pfn;
156         unsigned long end_of_phys_memory = 0UL;
157         unsigned long bootmap_pfn, bytes_avail, size;
158         int i;
159
160         bytes_avail = 0UL;
161         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
162                 end_of_phys_memory = sp_banks[i].base_addr +
163                         sp_banks[i].num_bytes;
164                 bytes_avail += sp_banks[i].num_bytes;
165                 if (cmdline_memory_size) {
166                         if (bytes_avail > cmdline_memory_size) {
167                                 unsigned long slack = bytes_avail - cmdline_memory_size;
168
169                                 bytes_avail -= slack;
170                                 end_of_phys_memory -= slack;
171
172                                 sp_banks[i].num_bytes -= slack;
173                                 if (sp_banks[i].num_bytes == 0) {
174                                         sp_banks[i].base_addr = 0xdeadbeef;
175                                 } else {
176                                         sp_banks[i+1].num_bytes = 0;
177                                         sp_banks[i+1].base_addr = 0xdeadbeef;
178                                 }
179                                 break;
180                         }
181                 }
182         }
183
184         /* Start with page aligned address of last symbol in kernel
185          * image.  
186          */
187         start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
188
189         /* Now shift down to get the real physical page frame number. */
190         start_pfn >>= PAGE_SHIFT;
191
192         bootmap_pfn = start_pfn;
193
194         max_pfn = end_of_phys_memory >> PAGE_SHIFT;
195
196         max_low_pfn = max_pfn;
197         highstart_pfn = highend_pfn = max_pfn;
198
199         if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
200                 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
201                 max_low_pfn = calc_max_low_pfn();
202                 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
203                     calc_highpages() >> (20 - PAGE_SHIFT));
204         }
205
206 #ifdef CONFIG_BLK_DEV_INITRD
207         /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
208         if (sparc_ramdisk_image) {
209                 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
210                         sparc_ramdisk_image -= KERNBASE;
211                 initrd_start = sparc_ramdisk_image + phys_base;
212                 initrd_end = initrd_start + sparc_ramdisk_size;
213                 if (initrd_end > end_of_phys_memory) {
214                         printk(KERN_CRIT "initrd extends beyond end of memory "
215                                          "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
216                                initrd_end, end_of_phys_memory);
217                         initrd_start = 0;
218                 }
219                 if (initrd_start) {
220                         if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
221                             initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
222                                 bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
223                 }
224         }
225 #endif  
226         /* Initialize the boot-time allocator. */
227         bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
228                                          max_low_pfn);
229
230         /* Now register the available physical memory with the
231          * allocator.
232          */
233         *pages_avail = 0;
234         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
235                 unsigned long curr_pfn, last_pfn;
236
237                 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
238                 if (curr_pfn >= max_low_pfn)
239                         break;
240
241                 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
242                 if (last_pfn > max_low_pfn)
243                         last_pfn = max_low_pfn;
244
245                 /*
246                  * .. finally, did all the rounding and playing
247                  * around just make the area go away?
248                  */
249                 if (last_pfn <= curr_pfn)
250                         continue;
251
252                 size = (last_pfn - curr_pfn) << PAGE_SHIFT;
253                 *pages_avail += last_pfn - curr_pfn;
254
255                 free_bootmem(sp_banks[i].base_addr, size);
256         }
257
258 #ifdef CONFIG_BLK_DEV_INITRD
259         if (initrd_start) {
260                 /* Reserve the initrd image area. */
261                 size = initrd_end - initrd_start;
262                 reserve_bootmem(initrd_start, size);
263                 *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
264
265                 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
266                 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;            
267         }
268 #endif
269         /* Reserve the kernel text/data/bss. */
270         size = (start_pfn << PAGE_SHIFT) - phys_base;
271         reserve_bootmem(phys_base, size);
272         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
273
274         /* Reserve the bootmem map.   We do not account for it
275          * in pages_avail because we will release that memory
276          * in free_all_bootmem.
277          */
278         size = bootmap_size;
279         reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size);
280         *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
281
282         return max_pfn;
283 }
284
285 /*
286  * check_pgt_cache
287  *
288  * This is called at the end of unmapping of VMA (zap_page_range),
289  * to rescan the page cache for architecture specific things,
290  * presumably something like sun4/sun4c PMEGs. Most architectures
291  * define check_pgt_cache empty.
292  *
293  * We simply copy the 2.4 implementation for now.
294  */
295 int pgt_cache_water[2] = { 25, 50 };
296
297 void check_pgt_cache(void)
298 {
299         do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
300 }
301
302 /*
303  * paging_init() sets up the page tables: We call the MMU specific
304  * init routine based upon the Sun model type on the Sparc.
305  *
306  */
307 extern void sun4c_paging_init(void);
308 extern void srmmu_paging_init(void);
309 extern void device_scan(void);
310
311 void __init paging_init(void)
312 {
313         switch(sparc_cpu_model) {
314         case sun4c:
315         case sun4e:
316         case sun4:
317                 sun4c_paging_init();
318                 sparc_unmapped_base = 0xe0000000;
319                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
320                 break;
321         case sun4m:
322         case sun4d:
323                 srmmu_paging_init();
324                 sparc_unmapped_base = 0x50000000;
325                 BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
326                 break;
327         default:
328                 prom_printf("paging_init: Cannot init paging on this Sparc\n");
329                 prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
330                 prom_printf("paging_init: Halting...\n");
331                 prom_halt();
332         };
333
334         /* Initialize the protection map with non-constant, MMU dependent values. */
335         protection_map[0] = PAGE_NONE;
336         protection_map[1] = PAGE_READONLY;
337         protection_map[2] = PAGE_COPY;
338         protection_map[3] = PAGE_COPY;
339         protection_map[4] = PAGE_READONLY;
340         protection_map[5] = PAGE_READONLY;
341         protection_map[6] = PAGE_COPY;
342         protection_map[7] = PAGE_COPY;
343         protection_map[8] = PAGE_NONE;
344         protection_map[9] = PAGE_READONLY;
345         protection_map[10] = PAGE_SHARED;
346         protection_map[11] = PAGE_SHARED;
347         protection_map[12] = PAGE_READONLY;
348         protection_map[13] = PAGE_READONLY;
349         protection_map[14] = PAGE_SHARED;
350         protection_map[15] = PAGE_SHARED;
351         btfixup();
352         device_scan();
353 }
354
355 struct cache_palias *sparc_aliases;
356
357 static void __init taint_real_pages(void)
358 {
359         int i;
360
361         for (i = 0; sp_banks[i].num_bytes; i++) {
362                 unsigned long start, end;
363
364                 start = sp_banks[i].base_addr;
365                 end = start + sp_banks[i].num_bytes;
366
367                 while (start < end) {
368                         set_bit(start >> 20, sparc_valid_addr_bitmap);
369                         start += PAGE_SIZE;
370                 }
371         }
372 }
373
374 void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
375 {
376         unsigned long tmp;
377
378 #ifdef CONFIG_DEBUG_HIGHMEM
379         printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
380 #endif
381
382         for (tmp = start_pfn; tmp < end_pfn; tmp++) {
383                 struct page *page = pfn_to_page(tmp);
384
385                 ClearPageReserved(page);
386                 init_page_count(page);
387                 __free_page(page);
388                 totalhigh_pages++;
389         }
390 }
391
392 void __init mem_init(void)
393 {
394         int codepages = 0;
395         int datapages = 0;
396         int initpages = 0; 
397         int reservedpages = 0;
398         int i;
399
400         if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
401                 prom_printf("BUG: fixmap and pkmap areas overlap\n");
402                 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
403                        PKMAP_BASE,
404                        (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
405                        FIXADDR_START);
406                 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
407                 prom_halt();
408         }
409
410
411         /* Saves us work later. */
412         memset((void *)&empty_zero_page, 0, PAGE_SIZE);
413
414         i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
415         i += 1;
416         sparc_valid_addr_bitmap = (unsigned long *)
417                 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
418
419         if (sparc_valid_addr_bitmap == NULL) {
420                 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
421                 prom_halt();
422         }
423         memset(sparc_valid_addr_bitmap, 0, i << 2);
424
425         taint_real_pages();
426
427         max_mapnr = last_valid_pfn - pfn_base;
428         high_memory = __va(max_low_pfn << PAGE_SHIFT);
429
430         totalram_pages = free_all_bootmem();
431
432         for (i = 0; sp_banks[i].num_bytes != 0; i++) {
433                 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
434                 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
435
436                 num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
437
438                 if (end_pfn <= highstart_pfn)
439                         continue;
440
441                 if (start_pfn < highstart_pfn)
442                         start_pfn = highstart_pfn;
443
444                 map_high_region(start_pfn, end_pfn);
445         }
446         
447         totalram_pages += totalhigh_pages;
448
449         codepages = (((unsigned long) &etext) - ((unsigned long)&_start));
450         codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
451         datapages = (((unsigned long) &edata) - ((unsigned long)&etext));
452         datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
453         initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
454         initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
455
456         /* Ignore memory holes for the purpose of counting reserved pages */
457         for (i=0; i < max_low_pfn; i++)
458                 if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
459                     && PageReserved(pfn_to_page(i)))
460                         reservedpages++;
461
462         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
463                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
464                num_physpages << (PAGE_SHIFT - 10),
465                codepages << (PAGE_SHIFT-10),
466                reservedpages << (PAGE_SHIFT - 10),
467                datapages << (PAGE_SHIFT-10), 
468                initpages << (PAGE_SHIFT-10),
469                totalhigh_pages << (PAGE_SHIFT-10));
470 }
471
472 void free_initmem (void)
473 {
474         unsigned long addr;
475
476         addr = (unsigned long)(&__init_begin);
477         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
478                 struct page *p;
479
480                 p = virt_to_page(addr);
481
482                 ClearPageReserved(p);
483                 init_page_count(p);
484                 __free_page(p);
485                 totalram_pages++;
486                 num_physpages++;
487         }
488         printk (KERN_INFO "Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10);
489 }
490
491 #ifdef CONFIG_BLK_DEV_INITRD
492 void free_initrd_mem(unsigned long start, unsigned long end)
493 {
494         if (start < end)
495                 printk (KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
496         for (; start < end; start += PAGE_SIZE) {
497                 struct page *p = virt_to_page(start);
498
499                 ClearPageReserved(p);
500                 init_page_count(p);
501                 __free_page(p);
502                 num_physpages++;
503         }
504 }
505 #endif
506
507 void sparc_flush_page_to_ram(struct page *page)
508 {
509         unsigned long vaddr = (unsigned long)page_address(page);
510
511         if (vaddr)
512                 __flush_page_to_ram(vaddr);
513 }