xref: /openbmc/linux/arch/sparc/mm/init_32.c (revision e8e0929d)
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 #include <asm/leon.h>
38 
39 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
40 
41 unsigned long *sparc_valid_addr_bitmap;
42 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
43 
44 unsigned long phys_base;
45 EXPORT_SYMBOL(phys_base);
46 
47 unsigned long pfn_base;
48 EXPORT_SYMBOL(pfn_base);
49 
50 unsigned long page_kernel;
51 EXPORT_SYMBOL(page_kernel);
52 
53 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
54 unsigned long sparc_unmapped_base;
55 
56 struct pgtable_cache_struct pgt_quicklists;
57 
58 /* Initial ramdisk setup */
59 extern unsigned int sparc_ramdisk_image;
60 extern unsigned int sparc_ramdisk_size;
61 
62 unsigned long highstart_pfn, highend_pfn;
63 
64 pte_t *kmap_pte;
65 pgprot_t kmap_prot;
66 
67 #define kmap_get_fixmap_pte(vaddr) \
68 	pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
69 
70 void __init kmap_init(void)
71 {
72 	/* cache the first kmap pte */
73 	kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
74 	kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
75 }
76 
77 void show_mem(void)
78 {
79 	printk("Mem-info:\n");
80 	show_free_areas();
81 	printk("Free swap:       %6ldkB\n",
82 	       nr_swap_pages << (PAGE_SHIFT-10));
83 	printk("%ld pages of RAM\n", totalram_pages);
84 	printk("%ld free pages\n", nr_free_pages());
85 #if 0 /* undefined pgtable_cache_size, pgd_cache_size */
86 	printk("%ld pages in page table cache\n",pgtable_cache_size);
87 #ifndef CONFIG_SMP
88 	if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
89 		printk("%ld entries in page dir cache\n",pgd_cache_size);
90 #endif
91 #endif
92 }
93 
94 void __init sparc_context_init(int numctx)
95 {
96 	int ctx;
97 
98 	ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
99 
100 	for(ctx = 0; ctx < numctx; ctx++) {
101 		struct ctx_list *clist;
102 
103 		clist = (ctx_list_pool + ctx);
104 		clist->ctx_number = ctx;
105 		clist->ctx_mm = NULL;
106 	}
107 	ctx_free.next = ctx_free.prev = &ctx_free;
108 	ctx_used.next = ctx_used.prev = &ctx_used;
109 	for(ctx = 0; ctx < numctx; ctx++)
110 		add_to_free_ctxlist(ctx_list_pool + ctx);
111 }
112 
113 extern unsigned long cmdline_memory_size;
114 unsigned long last_valid_pfn;
115 
116 unsigned long calc_highpages(void)
117 {
118 	int i;
119 	int nr = 0;
120 
121 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
122 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
123 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
124 
125 		if (end_pfn <= max_low_pfn)
126 			continue;
127 
128 		if (start_pfn < max_low_pfn)
129 			start_pfn = max_low_pfn;
130 
131 		nr += end_pfn - start_pfn;
132 	}
133 
134 	return nr;
135 }
136 
137 static unsigned long calc_max_low_pfn(void)
138 {
139 	int i;
140 	unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
141 	unsigned long curr_pfn, last_pfn;
142 
143 	last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
144 	for (i = 1; sp_banks[i].num_bytes != 0; i++) {
145 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
146 
147 		if (curr_pfn >= tmp) {
148 			if (last_pfn < tmp)
149 				tmp = last_pfn;
150 			break;
151 		}
152 
153 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
154 	}
155 
156 	return tmp;
157 }
158 
159 unsigned long __init bootmem_init(unsigned long *pages_avail)
160 {
161 	unsigned long bootmap_size, start_pfn;
162 	unsigned long end_of_phys_memory = 0UL;
163 	unsigned long bootmap_pfn, bytes_avail, size;
164 	int i;
165 
166 	bytes_avail = 0UL;
167 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
168 		end_of_phys_memory = sp_banks[i].base_addr +
169 			sp_banks[i].num_bytes;
170 		bytes_avail += sp_banks[i].num_bytes;
171 		if (cmdline_memory_size) {
172 			if (bytes_avail > cmdline_memory_size) {
173 				unsigned long slack = bytes_avail - cmdline_memory_size;
174 
175 				bytes_avail -= slack;
176 				end_of_phys_memory -= slack;
177 
178 				sp_banks[i].num_bytes -= slack;
179 				if (sp_banks[i].num_bytes == 0) {
180 					sp_banks[i].base_addr = 0xdeadbeef;
181 				} else {
182 					sp_banks[i+1].num_bytes = 0;
183 					sp_banks[i+1].base_addr = 0xdeadbeef;
184 				}
185 				break;
186 			}
187 		}
188 	}
189 
190 	/* Start with page aligned address of last symbol in kernel
191 	 * image.
192 	 */
193 	start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
194 
195 	/* Now shift down to get the real physical page frame number. */
196 	start_pfn >>= PAGE_SHIFT;
197 
198 	bootmap_pfn = start_pfn;
199 
200 	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
201 
202 	max_low_pfn = max_pfn;
203 	highstart_pfn = highend_pfn = max_pfn;
204 
205 	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
206 		highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
207 		max_low_pfn = calc_max_low_pfn();
208 		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
209 		    calc_highpages() >> (20 - PAGE_SHIFT));
210 	}
211 
212 #ifdef CONFIG_BLK_DEV_INITRD
213 	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
214 	if (sparc_ramdisk_image) {
215 		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
216 			sparc_ramdisk_image -= KERNBASE;
217 		initrd_start = sparc_ramdisk_image + phys_base;
218 		initrd_end = initrd_start + sparc_ramdisk_size;
219 		if (initrd_end > end_of_phys_memory) {
220 			printk(KERN_CRIT "initrd extends beyond end of memory "
221 		                 	 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
222 			       initrd_end, end_of_phys_memory);
223 			initrd_start = 0;
224 		}
225 		if (initrd_start) {
226 			if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
227 			    initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
228 				bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
229 		}
230 	}
231 #endif
232 	/* Initialize the boot-time allocator. */
233 	bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
234 					 max_low_pfn);
235 
236 	/* Now register the available physical memory with the
237 	 * allocator.
238 	 */
239 	*pages_avail = 0;
240 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
241 		unsigned long curr_pfn, last_pfn;
242 
243 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
244 		if (curr_pfn >= max_low_pfn)
245 			break;
246 
247 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
248 		if (last_pfn > max_low_pfn)
249 			last_pfn = max_low_pfn;
250 
251 		/*
252 		 * .. finally, did all the rounding and playing
253 		 * around just make the area go away?
254 		 */
255 		if (last_pfn <= curr_pfn)
256 			continue;
257 
258 		size = (last_pfn - curr_pfn) << PAGE_SHIFT;
259 		*pages_avail += last_pfn - curr_pfn;
260 
261 		free_bootmem(sp_banks[i].base_addr, size);
262 	}
263 
264 #ifdef CONFIG_BLK_DEV_INITRD
265 	if (initrd_start) {
266 		/* Reserve the initrd image area. */
267 		size = initrd_end - initrd_start;
268 		reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
269 		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
270 
271 		initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
272 		initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
273 	}
274 #endif
275 	/* Reserve the kernel text/data/bss. */
276 	size = (start_pfn << PAGE_SHIFT) - phys_base;
277 	reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
278 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
279 
280 	/* Reserve the bootmem map.   We do not account for it
281 	 * in pages_avail because we will release that memory
282 	 * in free_all_bootmem.
283 	 */
284 	size = bootmap_size;
285 	reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
286 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
287 
288 	return max_pfn;
289 }
290 
291 /*
292  * check_pgt_cache
293  *
294  * This is called at the end of unmapping of VMA (zap_page_range),
295  * to rescan the page cache for architecture specific things,
296  * presumably something like sun4/sun4c PMEGs. Most architectures
297  * define check_pgt_cache empty.
298  *
299  * We simply copy the 2.4 implementation for now.
300  */
301 static int pgt_cache_water[2] = { 25, 50 };
302 
303 void check_pgt_cache(void)
304 {
305 	do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
306 }
307 
308 /*
309  * paging_init() sets up the page tables: We call the MMU specific
310  * init routine based upon the Sun model type on the Sparc.
311  *
312  */
313 extern void sun4c_paging_init(void);
314 extern void srmmu_paging_init(void);
315 extern void device_scan(void);
316 
317 pgprot_t PAGE_SHARED __read_mostly;
318 EXPORT_SYMBOL(PAGE_SHARED);
319 
320 void __init paging_init(void)
321 {
322 	switch(sparc_cpu_model) {
323 	case sun4c:
324 	case sun4e:
325 	case sun4:
326 		sun4c_paging_init();
327 		sparc_unmapped_base = 0xe0000000;
328 		BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
329 		break;
330 	case sparc_leon:
331 		leon_init();
332 		/* fall through */
333 	case sun4m:
334 	case sun4d:
335 		srmmu_paging_init();
336 		sparc_unmapped_base = 0x50000000;
337 		BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
338 		break;
339 	default:
340 		prom_printf("paging_init: Cannot init paging on this Sparc\n");
341 		prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
342 		prom_printf("paging_init: Halting...\n");
343 		prom_halt();
344 	};
345 
346 	/* Initialize the protection map with non-constant, MMU dependent values. */
347 	protection_map[0] = PAGE_NONE;
348 	protection_map[1] = PAGE_READONLY;
349 	protection_map[2] = PAGE_COPY;
350 	protection_map[3] = PAGE_COPY;
351 	protection_map[4] = PAGE_READONLY;
352 	protection_map[5] = PAGE_READONLY;
353 	protection_map[6] = PAGE_COPY;
354 	protection_map[7] = PAGE_COPY;
355 	protection_map[8] = PAGE_NONE;
356 	protection_map[9] = PAGE_READONLY;
357 	protection_map[10] = PAGE_SHARED;
358 	protection_map[11] = PAGE_SHARED;
359 	protection_map[12] = PAGE_READONLY;
360 	protection_map[13] = PAGE_READONLY;
361 	protection_map[14] = PAGE_SHARED;
362 	protection_map[15] = PAGE_SHARED;
363 	btfixup();
364 	prom_build_devicetree();
365 	of_fill_in_cpu_data();
366 	device_scan();
367 }
368 
369 static void __init taint_real_pages(void)
370 {
371 	int i;
372 
373 	for (i = 0; sp_banks[i].num_bytes; i++) {
374 		unsigned long start, end;
375 
376 		start = sp_banks[i].base_addr;
377 		end = start + sp_banks[i].num_bytes;
378 
379 		while (start < end) {
380 			set_bit(start >> 20, sparc_valid_addr_bitmap);
381 			start += PAGE_SIZE;
382 		}
383 	}
384 }
385 
386 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
387 {
388 	unsigned long tmp;
389 
390 #ifdef CONFIG_DEBUG_HIGHMEM
391 	printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
392 #endif
393 
394 	for (tmp = start_pfn; tmp < end_pfn; tmp++) {
395 		struct page *page = pfn_to_page(tmp);
396 
397 		ClearPageReserved(page);
398 		init_page_count(page);
399 		__free_page(page);
400 		totalhigh_pages++;
401 	}
402 }
403 
404 void __init mem_init(void)
405 {
406 	int codepages = 0;
407 	int datapages = 0;
408 	int initpages = 0;
409 	int reservedpages = 0;
410 	int i;
411 
412 	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
413 		prom_printf("BUG: fixmap and pkmap areas overlap\n");
414 		prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
415 		       PKMAP_BASE,
416 		       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
417 		       FIXADDR_START);
418 		prom_printf("Please mail sparclinux@vger.kernel.org.\n");
419 		prom_halt();
420 	}
421 
422 
423 	/* Saves us work later. */
424 	memset((void *)&empty_zero_page, 0, PAGE_SIZE);
425 
426 	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
427 	i += 1;
428 	sparc_valid_addr_bitmap = (unsigned long *)
429 		__alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
430 
431 	if (sparc_valid_addr_bitmap == NULL) {
432 		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
433 		prom_halt();
434 	}
435 	memset(sparc_valid_addr_bitmap, 0, i << 2);
436 
437 	taint_real_pages();
438 
439 	max_mapnr = last_valid_pfn - pfn_base;
440 	high_memory = __va(max_low_pfn << PAGE_SHIFT);
441 
442 	totalram_pages = free_all_bootmem();
443 
444 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
445 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
446 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
447 
448 		num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
449 
450 		if (end_pfn <= highstart_pfn)
451 			continue;
452 
453 		if (start_pfn < highstart_pfn)
454 			start_pfn = highstart_pfn;
455 
456 		map_high_region(start_pfn, end_pfn);
457 	}
458 
459 	totalram_pages += totalhigh_pages;
460 
461 	codepages = (((unsigned long) &_etext) - ((unsigned long)&_start));
462 	codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
463 	datapages = (((unsigned long) &_edata) - ((unsigned long)&_etext));
464 	datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
465 	initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
466 	initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
467 
468 	/* Ignore memory holes for the purpose of counting reserved pages */
469 	for (i=0; i < max_low_pfn; i++)
470 		if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
471 		    && PageReserved(pfn_to_page(i)))
472 			reservedpages++;
473 
474 	printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
475 	       nr_free_pages() << (PAGE_SHIFT-10),
476 	       num_physpages << (PAGE_SHIFT - 10),
477 	       codepages << (PAGE_SHIFT-10),
478 	       reservedpages << (PAGE_SHIFT - 10),
479 	       datapages << (PAGE_SHIFT-10),
480 	       initpages << (PAGE_SHIFT-10),
481 	       totalhigh_pages << (PAGE_SHIFT-10));
482 }
483 
484 void free_initmem (void)
485 {
486 	unsigned long addr;
487 	unsigned long freed;
488 
489 	addr = (unsigned long)(&__init_begin);
490 	freed = (unsigned long)(&__init_end) - addr;
491 	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
492 		struct page *p;
493 
494 		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
495 		p = virt_to_page(addr);
496 
497 		ClearPageReserved(p);
498 		init_page_count(p);
499 		__free_page(p);
500 		totalram_pages++;
501 		num_physpages++;
502 	}
503 	printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
504 		freed >> 10);
505 }
506 
507 #ifdef CONFIG_BLK_DEV_INITRD
508 void free_initrd_mem(unsigned long start, unsigned long end)
509 {
510 	if (start < end)
511 		printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
512 			(end - start) >> 10);
513 	for (; start < end; start += PAGE_SIZE) {
514 		struct page *p;
515 
516 		memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
517 		p = virt_to_page(start);
518 
519 		ClearPageReserved(p);
520 		init_page_count(p);
521 		__free_page(p);
522 		totalram_pages++;
523 		num_physpages++;
524 	}
525 }
526 #endif
527 
528 void sparc_flush_page_to_ram(struct page *page)
529 {
530 	unsigned long vaddr = (unsigned long)page_address(page);
531 
532 	if (vaddr)
533 		__flush_page_to_ram(vaddr);
534 }
535 EXPORT_SYMBOL(sparc_flush_page_to_ram);
536