File: /usr/src/linux/arch/sparc/mm/init.c

1     /*  $Id: init.c,v 1.99 2001/07/17 16:17:33 anton 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/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/swapctl.h>
22     #ifdef CONFIG_BLK_DEV_INITRD
23     #include <linux/blk.h>
24     #endif
25     #include <linux/init.h>
26     #include <linux/highmem.h>
27     #include <linux/bootmem.h>
28     
29     #include <asm/system.h>
30     #include <asm/segment.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/tlb.h>
36     
37     mmu_gather_t mmu_gathers[NR_CPUS];
38     
39     unsigned long *sparc_valid_addr_bitmap;
40     
41     unsigned long phys_base;
42     
43     unsigned long page_kernel;
44     
45     struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS];
46     unsigned long sparc_unmapped_base;
47     
48     struct pgtable_cache_struct pgt_quicklists;
49     
50     /* References to section boundaries */
51     extern char __init_begin, __init_end, _start, _end, etext , edata;
52     
53     /* Initial ramdisk setup */
54     extern unsigned int sparc_ramdisk_image;
55     extern unsigned int sparc_ramdisk_size;
56     
57     unsigned long highstart_pfn, highend_pfn;
58     unsigned long totalram_pages;
59     unsigned long totalhigh_pages;
60     
61     pte_t *kmap_pte;
62     pgprot_t kmap_prot;
63     
64     #define kmap_get_fixed_pte(vaddr) \
65     	pte_offset(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
66     
67     void __init kmap_init(void)
68     {
69     	/* cache the first kmap pte */
70     	kmap_pte = kmap_get_fixed_pte(FIX_KMAP_BEGIN);
71     	kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
72     }
73     
74     void show_mem(void)
75     {
76     	printk("Mem-info:\n");
77     	show_free_areas();
78     	printk("Free swap:       %6dkB\n",
79     	       nr_swap_pages << (PAGE_SHIFT-10));
80     	printk("%ld pages of RAM\n", totalram_pages);
81     	printk("%d free pages\n", nr_free_pages());
82     	printk("%ld pages in page table cache\n",pgtable_cache_size);
83     #ifndef CONFIG_SMP
84     	if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
85     		printk("%ld entries in page dir cache\n",pgd_cache_size);
86     #endif	
87     	show_buffers();
88     }
89     
90     extern pgprot_t protection_map[16];
91     
92     void __init sparc_context_init(int numctx)
93     {
94     	int ctx;
95     
96     	ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
97     
98     	for(ctx = 0; ctx < numctx; ctx++) {
99     		struct ctx_list *clist;
100     
101     		clist = (ctx_list_pool + ctx);
102     		clist->ctx_number = ctx;
103     		clist->ctx_mm = 0;
104     	}
105     	ctx_free.next = ctx_free.prev = &ctx_free;
106     	ctx_used.next = ctx_used.prev = &ctx_used;
107     	for(ctx = 0; ctx < numctx; ctx++)
108     		add_to_free_ctxlist(ctx_list_pool + ctx);
109     }
110     
111     #define DEBUG_BOOTMEM
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     unsigned long calc_max_low_pfn(void)
138     {
139     	int i;
140     	unsigned long tmp = (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, max_pfn;
162     	unsigned long end_of_phys_memory = 0UL;
163     	unsigned long bootmap_pfn, bytes_avail, size;
164     	int i;
165     
166     #ifdef DEBUG_BOOTMEM
167     	prom_printf("bootmem_init: Scan sp_banks,  ");
168     #endif
169     	bytes_avail = 0UL;
170     	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
171     		end_of_phys_memory = sp_banks[i].base_addr +
172     			sp_banks[i].num_bytes;
173     		bytes_avail += sp_banks[i].num_bytes;
174     		if (cmdline_memory_size) {
175     			if (bytes_avail > cmdline_memory_size) {
176     				unsigned long slack = bytes_avail - cmdline_memory_size;
177     
178     				bytes_avail -= slack;
179     				end_of_phys_memory -= slack;
180     
181     				sp_banks[i].num_bytes -= slack;
182     				if (sp_banks[i].num_bytes == 0) {
183     					sp_banks[i].base_addr = 0xdeadbeef;
184     				} else {
185     					sp_banks[i+1].num_bytes = 0;
186     					sp_banks[i+1].base_addr = 0xdeadbeef;
187     				}
188     				break;
189     			}
190     		}
191     	}
192     
193     	/* Start with page aligned address of last symbol in kernel
194     	 * image.  
195     	 */
196     	start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
197     
198     	/* Adjust up to the physical address where the kernel begins. */
199     	start_pfn += phys_base;
200     
201     	/* Now shift down to get the real physical page frame number. */
202     	start_pfn >>= PAGE_SHIFT;
203     
204     	bootmap_pfn = start_pfn;
205     
206     	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
207     
208     	max_low_pfn = max_pfn;
209     	highstart_pfn = highend_pfn = max_pfn;
210     
211     	if (max_low_pfn > (SRMMU_MAXMEM >> PAGE_SHIFT)) {
212     		highstart_pfn = (SRMMU_MAXMEM >> PAGE_SHIFT);
213     		max_low_pfn = calc_max_low_pfn();
214     		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n", calc_highpages());
215     	}
216     
217     #ifdef CONFIG_BLK_DEV_INITRD
218     	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
219     	if (sparc_ramdisk_image) {
220     		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
221     			sparc_ramdisk_image -= KERNBASE;
222     		initrd_start = sparc_ramdisk_image + phys_base;
223     		initrd_end = initrd_start + sparc_ramdisk_size;
224     		if (initrd_end > end_of_phys_memory) {
225     			printk(KERN_CRIT "initrd extends beyond end of memory "
226     		                 	 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
227     			       initrd_end, end_of_phys_memory);
228     			initrd_start = 0;
229     		}
230     		if (initrd_start) {
231     			if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
232     			    initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
233     				bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
234     		}
235     	}
236     #endif	
237     	/* Initialize the boot-time allocator. */
238     #ifdef DEBUG_BOOTMEM
239     	prom_printf("init_bootmem(spfn[%lx],bpfn[%lx],mlpfn[%lx])\n",
240     		    start_pfn, bootmap_pfn, max_low_pfn);
241     #endif
242     	bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, phys_base>>PAGE_SHIFT, max_low_pfn);
243     
244     	/* Now register the available physical memory with the
245     	 * allocator.
246     	 */
247     	*pages_avail = 0;
248     	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
249     		unsigned long curr_pfn, last_pfn;
250     
251     		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
252     		if (curr_pfn >= max_low_pfn)
253     			break;
254     
255     		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
256     		if (last_pfn > max_low_pfn)
257     			last_pfn = max_low_pfn;
258     
259     		/*
260     		 * .. finally, did all the rounding and playing
261     		 * around just make the area go away?
262     		 */
263     		if (last_pfn <= curr_pfn)
264     			continue;
265     
266     		size = (last_pfn - curr_pfn) << PAGE_SHIFT;
267     		*pages_avail += last_pfn - curr_pfn;
268     #ifdef DEBUG_BOOTMEM
269     		prom_printf("free_bootmem: base[%lx] size[%lx]\n",
270     			    sp_banks[i].base_addr,
271     			    size);
272     #endif
273     		free_bootmem(sp_banks[i].base_addr,
274     			     size);
275     	}
276     
277     #ifdef CONFIG_BLK_DEV_INITRD
278     	if (initrd_start) {
279     		size = initrd_end - initrd_start;
280     #ifdef DEBUG_BOOTMEM
281     		prom_printf("reserve_bootmem: base[%lx] size[%lx]\n",
282     			     initrd_start, size);
283     #endif
284     		/* Reserve the initrd image area. */
285     		reserve_bootmem(initrd_start, size);
286     		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
287     
288     		initrd_start += PAGE_OFFSET;
289     		initrd_end += PAGE_OFFSET;
290     	}
291     #endif
292     	/* Reserve the kernel text/data/bss. */
293     	size = (start_pfn << PAGE_SHIFT) - phys_base;
294     #ifdef DEBUG_BOOTMEM
295     	prom_printf("reserve_bootmem: base[%lx] size[%lx]\n", phys_base, size);
296     #endif
297     	reserve_bootmem(phys_base, size);
298     	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
299     
300     	/* Reserve the bootmem map.   We do not account for it
301     	 * in pages_avail because we will release that memory
302     	 * in free_all_bootmem.
303     	 */
304     	size = bootmap_size;
305     #ifdef DEBUG_BOOTMEM
306     	prom_printf("reserve_bootmem: base[%lx] size[%lx]\n",
307     		    (bootmap_pfn << PAGE_SHIFT), size);
308     #endif
309     	reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size);
310     	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
311     
312     	return max_pfn;
313     }
314     
315     /*
316      * paging_init() sets up the page tables: We call the MMU specific
317      * init routine based upon the Sun model type on the Sparc.
318      *
319      */
320     extern void sun4c_paging_init(void);
321     extern void srmmu_paging_init(void);
322     extern void device_scan(void);
323     
324     void __init paging_init(void)
325     {
326     	switch(sparc_cpu_model) {
327     	case sun4c:
328     	case sun4e:
329     	case sun4:
330     		sun4c_paging_init();
331     		sparc_unmapped_base = 0xe0000000;
332     		BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
333     		break;
334     	case sun4m:
335     	case sun4d:
336     		srmmu_paging_init();
337     		sparc_unmapped_base = 0x50000000;
338     		BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
339     		break;
340     	default:
341     		prom_printf("paging_init: Cannot init paging on this Sparc\n");
342     		prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
343     		prom_printf("paging_init: Halting...\n");
344     		prom_halt();
345     	};
346     
347     	/* Initialize the protection map with non-constant, MMU dependent values. */
348     	protection_map[0] = PAGE_NONE;
349     	protection_map[1] = PAGE_READONLY;
350     	protection_map[2] = PAGE_COPY;
351     	protection_map[3] = PAGE_COPY;
352     	protection_map[4] = PAGE_READONLY;
353     	protection_map[5] = PAGE_READONLY;
354     	protection_map[6] = PAGE_COPY;
355     	protection_map[7] = PAGE_COPY;
356     	protection_map[8] = PAGE_NONE;
357     	protection_map[9] = PAGE_READONLY;
358     	protection_map[10] = PAGE_SHARED;
359     	protection_map[11] = PAGE_SHARED;
360     	protection_map[12] = PAGE_READONLY;
361     	protection_map[13] = PAGE_READONLY;
362     	protection_map[14] = PAGE_SHARED;
363     	protection_map[15] = PAGE_SHARED;
364     	btfixup();
365     	device_scan();
366     }
367     
368     struct cache_palias *sparc_aliases;
369     
370     static void __init taint_real_pages(void)
371     {
372     	int i;
373     
374     	for (i = 0; sp_banks[i].num_bytes; i++) {
375     		unsigned long start, end;
376     
377     		start = sp_banks[i].base_addr;
378     		end = start + sp_banks[i].num_bytes;
379     
380     		while (start < end) {
381     			set_bit (start >> 20,
382     				sparc_valid_addr_bitmap);
383     				start += PAGE_SIZE;
384     		}
385     	}
386     }
387     
388     void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
389     {
390     	unsigned long tmp;
391     
392     #ifdef DEBUG_HIGHMEM
393     	printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
394     #endif
395     
396     	for (tmp = start_pfn; tmp < end_pfn; tmp++) {
397     		struct page *page = mem_map + tmp;
398     
399     		ClearPageReserved(page);
400     		set_bit(PG_highmem, &page->flags);
401     		atomic_set(&page->count, 1);
402     		__free_page(page);
403     		totalhigh_pages++;
404     	}
405     }
406     
407     void __init mem_init(void)
408     {
409     	int codepages = 0;
410     	int datapages = 0;
411     	int initpages = 0; 
412     	int i;
413     #ifdef CONFIG_BLK_DEV_INITRD
414     	unsigned long addr, last;
415     #endif
416     
417     	highmem_start_page = mem_map + highstart_pfn;
418     
419     	/* Saves us work later. */
420     	memset((void *)&empty_zero_page, 0, PAGE_SIZE);
421     
422     	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
423     	i += 1;
424     	sparc_valid_addr_bitmap = (unsigned long *)
425     		__alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
426     
427     	if (sparc_valid_addr_bitmap == NULL) {
428     		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
429     		prom_halt();
430     	}
431     	memset(sparc_valid_addr_bitmap, 0, i << 2);
432     
433     	taint_real_pages();
434     
435     	max_mapnr = last_valid_pfn - (phys_base >> PAGE_SHIFT);
436     	high_memory = __va(max_low_pfn << PAGE_SHIFT);
437     
438     #ifdef DEBUG_BOOTMEM
439     	prom_printf("mem_init: Calling free_all_bootmem().\n");
440     #endif
441     	num_physpages = 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     		if (end_pfn <= highstart_pfn)
448     			continue;
449     
450     		if (start_pfn < highstart_pfn)
451     			start_pfn = highstart_pfn;
452     
453     		map_high_region(start_pfn, end_pfn);
454     	}
455     	
456     	totalram_pages += totalhigh_pages;
457     
458     	codepages = (((unsigned long) &etext) - ((unsigned long)&_start));
459     	codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
460     	datapages = (((unsigned long) &edata) - ((unsigned long)&etext));
461     	datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
462     	initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
463     	initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
464     
465     	printk("Memory: %dk available (%dk kernel code, %dk data, %dk init, %ldk highmem) [%08lx,%08lx]\n",
466     	       nr_free_pages() << (PAGE_SHIFT-10),
467     	       codepages << (PAGE_SHIFT-10),
468     	       datapages << (PAGE_SHIFT-10), 
469     	       initpages << (PAGE_SHIFT-10),
470     	       totalhigh_pages << (PAGE_SHIFT-10),
471     	       (unsigned long)PAGE_OFFSET, (last_valid_pfn << PAGE_SHIFT));
472     }
473     
474     void free_initmem (void)
475     {
476     	unsigned long addr;
477     
478     	addr = (unsigned long)(&__init_begin);
479     	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
480     		unsigned long page;
481     		struct page *p;
482     
483     		page = addr + phys_base;
484     		p = virt_to_page(page);
485     
486     		ClearPageReserved(p);
487     		set_page_count(p, 1);
488     		__free_page(p);
489     		totalram_pages++;
490     		num_physpages++;
491     	}
492     	printk ("Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10);
493     }
494     
495     #ifdef CONFIG_BLK_DEV_INITRD
496     void free_initrd_mem(unsigned long start, unsigned long end)
497     {
498     	if (start < end)
499     		printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
500     	for (; start < end; start += PAGE_SIZE) {
501     		struct page *p = virt_to_page(start);
502     
503     		ClearPageReserved(p);
504     		set_page_count(p, 1);
505     		__free_page(p);
506     		num_physpages++;
507     	}
508     }
509     #endif
510     
511     void si_meminfo(struct sysinfo *val)
512     {
513     	val->totalram = totalram_pages;
514     	val->sharedram = 0;
515     	val->freeram = nr_free_pages();
516     	val->bufferram = atomic_read(&buffermem_pages);
517     	val->totalhigh = totalhigh_pages;
518     	val->freehigh = nr_free_highpages();
519     
520     	val->mem_unit = PAGE_SIZE;
521     }
522     
523     void 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