• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 
28 #include <asm/sections.h>
29 #include <asm/system.h>
30 #include <asm/vac-ops.h>
31 #include <asm/page.h>
32 #include <asm/pgtable.h>
33 #include <asm/vaddrs.h>
34 #include <asm/pgalloc.h>	/* bug in asm-generic/tlb.h: check_pgt_cache */
35 #include <asm/tlb.h>
36 #include <asm/prom.h>
37 
38 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
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 
kmap_init(void)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 
show_mem(void)76 void show_mem(void)
77 {
78 	printk("Mem-info:\n");
79 	show_free_areas();
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 
sparc_context_init(int numctx)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 
calc_highpages(void)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 
calc_max_low_pfn(void)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 
bootmem_init(unsigned long * pages_avail)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 
check_pgt_cache(void)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 
paging_init(void)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 sun4m:
330 	case sun4d:
331 		srmmu_paging_init();
332 		sparc_unmapped_base = 0x50000000;
333 		BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
334 		break;
335 	default:
336 		prom_printf("paging_init: Cannot init paging on this Sparc\n");
337 		prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
338 		prom_printf("paging_init: Halting...\n");
339 		prom_halt();
340 	};
341 
342 	/* Initialize the protection map with non-constant, MMU dependent values. */
343 	protection_map[0] = PAGE_NONE;
344 	protection_map[1] = PAGE_READONLY;
345 	protection_map[2] = PAGE_COPY;
346 	protection_map[3] = PAGE_COPY;
347 	protection_map[4] = PAGE_READONLY;
348 	protection_map[5] = PAGE_READONLY;
349 	protection_map[6] = PAGE_COPY;
350 	protection_map[7] = PAGE_COPY;
351 	protection_map[8] = PAGE_NONE;
352 	protection_map[9] = PAGE_READONLY;
353 	protection_map[10] = PAGE_SHARED;
354 	protection_map[11] = PAGE_SHARED;
355 	protection_map[12] = PAGE_READONLY;
356 	protection_map[13] = PAGE_READONLY;
357 	protection_map[14] = PAGE_SHARED;
358 	protection_map[15] = PAGE_SHARED;
359 	btfixup();
360 	prom_build_devicetree();
361 	device_scan();
362 }
363 
taint_real_pages(void)364 static void __init taint_real_pages(void)
365 {
366 	int i;
367 
368 	for (i = 0; sp_banks[i].num_bytes; i++) {
369 		unsigned long start, end;
370 
371 		start = sp_banks[i].base_addr;
372 		end = start + sp_banks[i].num_bytes;
373 
374 		while (start < end) {
375 			set_bit(start >> 20, sparc_valid_addr_bitmap);
376 			start += PAGE_SIZE;
377 		}
378 	}
379 }
380 
map_high_region(unsigned long start_pfn,unsigned long end_pfn)381 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
382 {
383 	unsigned long tmp;
384 
385 #ifdef CONFIG_DEBUG_HIGHMEM
386 	printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
387 #endif
388 
389 	for (tmp = start_pfn; tmp < end_pfn; tmp++) {
390 		struct page *page = pfn_to_page(tmp);
391 
392 		ClearPageReserved(page);
393 		init_page_count(page);
394 		__free_page(page);
395 		totalhigh_pages++;
396 	}
397 }
398 
mem_init(void)399 void __init mem_init(void)
400 {
401 	int codepages = 0;
402 	int datapages = 0;
403 	int initpages = 0;
404 	int reservedpages = 0;
405 	int i;
406 
407 	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
408 		prom_printf("BUG: fixmap and pkmap areas overlap\n");
409 		prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
410 		       PKMAP_BASE,
411 		       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
412 		       FIXADDR_START);
413 		prom_printf("Please mail sparclinux@vger.kernel.org.\n");
414 		prom_halt();
415 	}
416 
417 
418 	/* Saves us work later. */
419 	memset((void *)&empty_zero_page, 0, PAGE_SIZE);
420 
421 	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
422 	i += 1;
423 	sparc_valid_addr_bitmap = (unsigned long *)
424 		__alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
425 
426 	if (sparc_valid_addr_bitmap == NULL) {
427 		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
428 		prom_halt();
429 	}
430 	memset(sparc_valid_addr_bitmap, 0, i << 2);
431 
432 	taint_real_pages();
433 
434 	max_mapnr = last_valid_pfn - pfn_base;
435 	high_memory = __va(max_low_pfn << PAGE_SHIFT);
436 
437 	totalram_pages = free_all_bootmem();
438 
439 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
440 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
441 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
442 
443 		num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
444 
445 		if (end_pfn <= highstart_pfn)
446 			continue;
447 
448 		if (start_pfn < highstart_pfn)
449 			start_pfn = highstart_pfn;
450 
451 		map_high_region(start_pfn, end_pfn);
452 	}
453 
454 	totalram_pages += totalhigh_pages;
455 
456 	codepages = (((unsigned long) &_etext) - ((unsigned long)&_start));
457 	codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
458 	datapages = (((unsigned long) &_edata) - ((unsigned long)&_etext));
459 	datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
460 	initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
461 	initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
462 
463 	/* Ignore memory holes for the purpose of counting reserved pages */
464 	for (i=0; i < max_low_pfn; i++)
465 		if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
466 		    && PageReserved(pfn_to_page(i)))
467 			reservedpages++;
468 
469 	printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
470 	       (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
471 	       num_physpages << (PAGE_SHIFT - 10),
472 	       codepages << (PAGE_SHIFT-10),
473 	       reservedpages << (PAGE_SHIFT - 10),
474 	       datapages << (PAGE_SHIFT-10),
475 	       initpages << (PAGE_SHIFT-10),
476 	       totalhigh_pages << (PAGE_SHIFT-10));
477 }
478 
free_initmem(void)479 void free_initmem (void)
480 {
481 	unsigned long addr;
482 	unsigned long freed;
483 
484 	addr = (unsigned long)(&__init_begin);
485 	freed = (unsigned long)(&__init_end) - addr;
486 	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
487 		struct page *p;
488 
489 		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
490 		p = virt_to_page(addr);
491 
492 		ClearPageReserved(p);
493 		init_page_count(p);
494 		__free_page(p);
495 		totalram_pages++;
496 		num_physpages++;
497 	}
498 	printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
499 		freed >> 10);
500 }
501 
502 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)503 void free_initrd_mem(unsigned long start, unsigned long end)
504 {
505 	if (start < end)
506 		printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
507 			(end - start) >> 10);
508 	for (; start < end; start += PAGE_SIZE) {
509 		struct page *p;
510 
511 		memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
512 		p = virt_to_page(start);
513 
514 		ClearPageReserved(p);
515 		init_page_count(p);
516 		__free_page(p);
517 		totalram_pages++;
518 		num_physpages++;
519 	}
520 }
521 #endif
522 
sparc_flush_page_to_ram(struct page * page)523 void sparc_flush_page_to_ram(struct page *page)
524 {
525 	unsigned long vaddr = (unsigned long)page_address(page);
526 
527 	if (vaddr)
528 		__flush_page_to_ram(vaddr);
529 }
530 EXPORT_SYMBOL(sparc_flush_page_to_ram);
531