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 by Ralf Baechle
7 * Copyright (C) 2000 Silicon Graphics, Inc.
8 *
9 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
10 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
11 */
12 #include <linux/config.h>
13 #include <linux/init.h>
14 #include <linux/signal.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/errno.h>
18 #include <linux/string.h>
19 #include <linux/types.h>
20 #include <linux/pagemap.h>
21 #include <linux/ptrace.h>
22 #include <linux/mman.h>
23 #include <linux/mm.h>
24 #include <linux/bootmem.h>
25 #include <linux/highmem.h>
26 #include <linux/swap.h>
27 #include <linux/swapctl.h>
28 #include <linux/blk.h>
29
30 #include <asm/bootinfo.h>
31 #include <asm/cachectl.h>
32 #include <asm/cpu.h>
33 #include <asm/dma.h>
34 #include <asm/jazzdma.h>
35 #include <asm/system.h>
36 #include <asm/pgtable.h>
37 #include <asm/pgalloc.h>
38 #include <asm/mmu_context.h>
39 #include <asm/tlb.h>
40
41 mmu_gather_t mmu_gathers[NR_CPUS];
42 unsigned long highstart_pfn, highend_pfn;
43 static unsigned long totalram_pages;
44 static unsigned long totalhigh_pages;
45
pgd_init(unsigned long page)46 void pgd_init(unsigned long page)
47 {
48 unsigned long *p = (unsigned long *) page;
49 int i;
50
51 for (i = 0; i < USER_PTRS_PER_PGD; i+=8) {
52 p[i + 0] = (unsigned long) invalid_pte_table;
53 p[i + 1] = (unsigned long) invalid_pte_table;
54 p[i + 2] = (unsigned long) invalid_pte_table;
55 p[i + 3] = (unsigned long) invalid_pte_table;
56 p[i + 4] = (unsigned long) invalid_pte_table;
57 p[i + 5] = (unsigned long) invalid_pte_table;
58 p[i + 6] = (unsigned long) invalid_pte_table;
59 p[i + 7] = (unsigned long) invalid_pte_table;
60 }
61 }
62
63 /*
64 * We have upto 8 empty zeroed pages so we can map one of the right colour
65 * when needed. This is necessary only on R4000 / R4400 SC and MC versions
66 * where we have to avoid VCED / VECI exceptions for good performance at
67 * any price. Since page is never written to after the initialization we
68 * don't have to care about aliases on other CPUs.
69 */
70 unsigned long empty_zero_page, zero_page_mask;
71
setup_zero_pages(void)72 static inline unsigned long setup_zero_pages(void)
73 {
74 unsigned long order, size;
75 struct page *page;
76
77 if (cpu_has_vce)
78 order = 3;
79 else
80 order = 0;
81
82 empty_zero_page = __get_free_pages(GFP_KERNEL, order);
83 if (!empty_zero_page)
84 panic("Oh boy, that early out of memory?");
85
86 page = virt_to_page(empty_zero_page);
87 while (page < virt_to_page(empty_zero_page + (PAGE_SIZE << order))) {
88 set_bit(PG_reserved, &page->flags);
89 set_page_count(page, 0);
90 page++;
91 }
92
93 size = PAGE_SIZE << order;
94 zero_page_mask = (size - 1) & PAGE_MASK;
95 memset((void *)empty_zero_page, 0, size);
96
97 return 1UL << order;
98 }
99
do_check_pgt_cache(int low,int high)100 int do_check_pgt_cache(int low, int high)
101 {
102 int freed = 0;
103
104 if (pgtable_cache_size > high) {
105 do {
106 if (pgd_quicklist)
107 free_pgd_slow(get_pgd_fast()), freed++;
108 if (pmd_quicklist)
109 free_pmd_slow(get_pmd_fast()), freed++;
110 if (pte_quicklist)
111 free_pte_slow(get_pte_fast()), freed++;
112 } while (pgtable_cache_size > low);
113 }
114 return freed;
115 }
116
117 #if CONFIG_HIGHMEM
118 pte_t *kmap_pte;
119 pgprot_t kmap_prot;
120
121 #define kmap_get_fixmap_pte(vaddr) \
122 pte_offset(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
123
kmap_init(void)124 static void __init kmap_init(void)
125 {
126 unsigned long kmap_vstart;
127
128 /* cache the first kmap pte */
129 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
130 kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
131
132 kmap_prot = PAGE_KERNEL;
133 }
134
135 #endif /* CONFIG_HIGHMEM */
136
show_mem(void)137 void show_mem(void)
138 {
139 int i, free = 0, total = 0, reserved = 0;
140 int shared = 0, cached = 0;
141
142 printk("Mem-info:\n");
143 show_free_areas();
144 printk("Free swap: %6dkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
145 i = max_mapnr;
146 while (i-- > 0) {
147 total++;
148 if (PageReserved(mem_map+i))
149 reserved++;
150 else if (PageSwapCache(mem_map+i))
151 cached++;
152 else if (!page_count(mem_map + i))
153 free++;
154 else
155 shared += page_count(mem_map + i) - 1;
156 }
157 printk("%d pages of RAM\n", total);
158 printk("%d reserved pages\n", reserved);
159 printk("%d pages shared\n", shared);
160 printk("%d pages swap cached\n",cached);
161 printk("%ld pages in page table cache\n",pgtable_cache_size);
162 printk("%d free pages\n", free);
163 show_buffers();
164 }
165
166 /* References to section boundaries */
167
168 extern char _ftext, _etext, _fdata, _edata;
169 extern char __init_begin, __init_end;
170
171 #ifdef CONFIG_HIGHMEM
fixrange_init(unsigned long start,unsigned long end,pgd_t * pgd_base)172 static void __init fixrange_init (unsigned long start, unsigned long end,
173 pgd_t *pgd_base)
174 {
175 pgd_t *pgd;
176 pmd_t *pmd;
177 pte_t *pte;
178 int i, j;
179 unsigned long vaddr;
180
181 vaddr = start;
182 i = __pgd_offset(vaddr);
183 j = __pmd_offset(vaddr);
184 pgd = pgd_base + i;
185
186 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
187 pmd = (pmd_t *)pgd;
188 for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
189 if (pmd_none(*pmd)) {
190 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
191 set_pmd(pmd, __pmd(pte));
192 if (pte != pte_offset(pmd, 0))
193 BUG();
194 }
195 vaddr += PMD_SIZE;
196 }
197 j = 0;
198 }
199 }
200 #endif
201
pagetable_init(void)202 void __init pagetable_init(void)
203 {
204 #ifdef CONFIG_HIGHMEM
205 unsigned long vaddr;
206 pgd_t *pgd, *pgd_base;
207 pmd_t *pmd;
208 pte_t *pte;
209 #endif
210
211 /* Initialize the entire pgd. */
212 pgd_init((unsigned long)swapper_pg_dir);
213 pgd_init((unsigned long)swapper_pg_dir +
214 sizeof(pgd_t ) * USER_PTRS_PER_PGD);
215
216 #ifdef CONFIG_HIGHMEM
217 pgd_base = swapper_pg_dir;
218
219 /*
220 * Fixed mappings:
221 */
222 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
223 fixrange_init(vaddr, 0, pgd_base);
224
225 /*
226 * Permanent kmaps:
227 */
228 vaddr = PKMAP_BASE;
229 fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
230
231 pgd = swapper_pg_dir + __pgd_offset(vaddr);
232 pmd = pmd_offset(pgd, vaddr);
233 pte = pte_offset(pmd, vaddr);
234 pkmap_page_table = pte;
235 #endif
236 }
237
paging_init(void)238 void __init paging_init(void)
239 {
240 unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
241 unsigned long max_dma, high, low;
242
243 pagetable_init();
244
245 #ifdef CONFIG_HIGHMEM
246 kmap_init();
247 #endif
248
249 max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
250 low = max_low_pfn;
251 high = highend_pfn;
252
253 #ifdef CONFIG_ISA
254 if (low < max_dma)
255 zones_size[ZONE_DMA] = low;
256 else {
257 zones_size[ZONE_DMA] = max_dma;
258 zones_size[ZONE_NORMAL] = low - max_dma;
259 }
260 #else
261 zones_size[ZONE_DMA] = low;
262 #endif
263 #ifdef CONFIG_HIGHMEM
264 if (cpu_has_dc_aliases) {
265 printk(KERN_WARNING "This processor doesn't support highmem.");
266 if (high - low)
267 printk(" %dk highmem ignored", high - low);
268 printk("\n");
269 } else
270 zones_size[ZONE_HIGHMEM] = high - low;
271 #endif
272
273 free_area_init(zones_size);
274 }
275
276 #define PFN_UP(x) (((x) + PAGE_SIZE - 1) >> PAGE_SHIFT)
277 #define PFN_DOWN(x) ((x) >> PAGE_SHIFT)
278
page_is_ram(unsigned long pagenr)279 static inline int page_is_ram(unsigned long pagenr)
280 {
281 int i;
282
283 for (i = 0; i < boot_mem_map.nr_map; i++) {
284 unsigned long addr, end;
285
286 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
287 /* not usable memory */
288 continue;
289
290 addr = PFN_UP(boot_mem_map.map[i].addr);
291 end = PFN_DOWN(boot_mem_map.map[i].addr
292 + boot_mem_map.map[i].size);
293
294 if (pagenr >= addr && pagenr < end)
295 return 1;
296 }
297
298 return 0;
299 }
300
mem_init(void)301 void __init mem_init(void)
302 {
303 unsigned long codesize, reservedpages, datasize, initsize;
304 unsigned long tmp, ram;
305
306 #if defined(CONFIG_DISCONTIGMEM) && defined(CONFIG_HIGHMEM)
307 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
308 #endif
309
310 #ifdef CONFIG_HIGHMEM
311 highstart_pfn = (KSEG1 - KSEG0) >> PAGE_SHIFT;
312 highmem_start_page = mem_map + highstart_pfn;
313 max_mapnr = num_physpages = highend_pfn;
314 num_mappedpages = max_low_pfn;
315 #else
316 max_mapnr = num_mappedpages = num_physpages = max_low_pfn;
317 #endif
318 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
319
320 totalram_pages += free_all_bootmem();
321 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */
322
323 reservedpages = ram = 0;
324 for (tmp = 0; tmp < max_low_pfn; tmp++)
325 if (page_is_ram(tmp)) {
326 ram++;
327 if (PageReserved(mem_map+tmp))
328 reservedpages++;
329 }
330
331 #ifdef CONFIG_HIGHMEM
332 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
333 struct page *page = mem_map + tmp;
334
335 if (!page_is_ram(tmp)) {
336 SetPageReserved(page);
337 continue;
338 }
339 ClearPageReserved(page);
340 set_bit(PG_highmem, &page->flags);
341 atomic_set(&page->count, 1);
342 __free_page(page);
343 totalhigh_pages++;
344 }
345 totalram_pages += totalhigh_pages;
346 #endif
347
348 codesize = (unsigned long) &_etext - (unsigned long) &_ftext;
349 datasize = (unsigned long) &_edata - (unsigned long) &_fdata;
350 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
351
352 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
353 "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
354 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
355 ram << (PAGE_SHIFT-10),
356 codesize >> 10,
357 reservedpages << (PAGE_SHIFT-10),
358 datasize >> 10,
359 initsize >> 10,
360 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
361 }
362
363 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)364 void free_initrd_mem(unsigned long start, unsigned long end)
365 {
366 if (start < end)
367 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
368 (end - start) >> 10);
369
370 for (; start < end; start += PAGE_SIZE) {
371 ClearPageReserved(virt_to_page(start));
372 set_page_count(virt_to_page(start), 1);
373 free_page(start);
374 totalram_pages++;
375 }
376 }
377 #endif
378
379 extern char __init_begin, __init_end;
380 extern void prom_free_prom_memory(void) __init;
381
free_initmem(void)382 void free_initmem(void)
383 {
384 unsigned long addr;
385
386 prom_free_prom_memory ();
387
388 addr = (unsigned long) &__init_begin;
389 while (addr < (unsigned long) &__init_end) {
390 ClearPageReserved(virt_to_page(addr));
391 set_page_count(virt_to_page(addr), 1);
392 free_page(addr);
393 totalram_pages++;
394 addr += PAGE_SIZE;
395 }
396 printk(KERN_INFO "Freeing unused kernel memory: %dk freed\n",
397 (&__init_end - &__init_begin) >> 10);
398 }
399
si_meminfo(struct sysinfo * val)400 void si_meminfo(struct sysinfo *val)
401 {
402 val->totalram = totalram_pages;
403 val->sharedram = 0;
404 val->freeram = nr_free_pages();
405 val->bufferram = atomic_read(&buffermem_pages);
406 val->totalhigh = totalhigh_pages;
407 val->freehigh = nr_free_highpages();
408 val->mem_unit = PAGE_SIZE;
409
410 return;
411 }
412