xref: /openbmc/linux/arch/parisc/mm/init.c (revision 93dc544c)
1 /*
2  *  linux/arch/parisc/mm/init.c
3  *
4  *  Copyright (C) 1995	Linus Torvalds
5  *  Copyright 1999 SuSE GmbH
6  *    changed by Philipp Rumpf
7  *  Copyright 1999 Philipp Rumpf (prumpf@tux.org)
8  *  Copyright 2004 Randolph Chung (tausq@debian.org)
9  *  Copyright 2006-2007 Helge Deller (deller@gmx.de)
10  *
11  */
12 
13 
14 #include <linux/module.h>
15 #include <linux/mm.h>
16 #include <linux/bootmem.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/pci.h>		/* for hppa_dma_ops and pcxl_dma_ops */
20 #include <linux/initrd.h>
21 #include <linux/swap.h>
22 #include <linux/unistd.h>
23 #include <linux/nodemask.h>	/* for node_online_map */
24 #include <linux/pagemap.h>	/* for release_pages and page_cache_release */
25 
26 #include <asm/pgalloc.h>
27 #include <asm/pgtable.h>
28 #include <asm/tlb.h>
29 #include <asm/pdc_chassis.h>
30 #include <asm/mmzone.h>
31 #include <asm/sections.h>
32 
33 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
34 
35 extern int  data_start;
36 
37 #ifdef CONFIG_DISCONTIGMEM
38 struct node_map_data node_data[MAX_NUMNODES] __read_mostly;
39 unsigned char pfnnid_map[PFNNID_MAP_MAX] __read_mostly;
40 #endif
41 
42 static struct resource data_resource = {
43 	.name	= "Kernel data",
44 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
45 };
46 
47 static struct resource code_resource = {
48 	.name	= "Kernel code",
49 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
50 };
51 
52 static struct resource pdcdata_resource = {
53 	.name	= "PDC data (Page Zero)",
54 	.start	= 0,
55 	.end	= 0x9ff,
56 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
57 };
58 
59 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __read_mostly;
60 
61 /* The following array is initialized from the firmware specific
62  * information retrieved in kernel/inventory.c.
63  */
64 
65 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __read_mostly;
66 int npmem_ranges __read_mostly;
67 
68 #ifdef CONFIG_64BIT
69 #define MAX_MEM         (~0UL)
70 #else /* !CONFIG_64BIT */
71 #define MAX_MEM         (3584U*1024U*1024U)
72 #endif /* !CONFIG_64BIT */
73 
74 static unsigned long mem_limit __read_mostly = MAX_MEM;
75 
76 static void __init mem_limit_func(void)
77 {
78 	char *cp, *end;
79 	unsigned long limit;
80 
81 	/* We need this before __setup() functions are called */
82 
83 	limit = MAX_MEM;
84 	for (cp = boot_command_line; *cp; ) {
85 		if (memcmp(cp, "mem=", 4) == 0) {
86 			cp += 4;
87 			limit = memparse(cp, &end);
88 			if (end != cp)
89 				break;
90 			cp = end;
91 		} else {
92 			while (*cp != ' ' && *cp)
93 				++cp;
94 			while (*cp == ' ')
95 				++cp;
96 		}
97 	}
98 
99 	if (limit < mem_limit)
100 		mem_limit = limit;
101 }
102 
103 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
104 
105 static void __init setup_bootmem(void)
106 {
107 	unsigned long bootmap_size;
108 	unsigned long mem_max;
109 	unsigned long bootmap_pages;
110 	unsigned long bootmap_start_pfn;
111 	unsigned long bootmap_pfn;
112 #ifndef CONFIG_DISCONTIGMEM
113 	physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
114 	int npmem_holes;
115 #endif
116 	int i, sysram_resource_count;
117 
118 	disable_sr_hashing(); /* Turn off space register hashing */
119 
120 	/*
121 	 * Sort the ranges. Since the number of ranges is typically
122 	 * small, and performance is not an issue here, just do
123 	 * a simple insertion sort.
124 	 */
125 
126 	for (i = 1; i < npmem_ranges; i++) {
127 		int j;
128 
129 		for (j = i; j > 0; j--) {
130 			unsigned long tmp;
131 
132 			if (pmem_ranges[j-1].start_pfn <
133 			    pmem_ranges[j].start_pfn) {
134 
135 				break;
136 			}
137 			tmp = pmem_ranges[j-1].start_pfn;
138 			pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn;
139 			pmem_ranges[j].start_pfn = tmp;
140 			tmp = pmem_ranges[j-1].pages;
141 			pmem_ranges[j-1].pages = pmem_ranges[j].pages;
142 			pmem_ranges[j].pages = tmp;
143 		}
144 	}
145 
146 #ifndef CONFIG_DISCONTIGMEM
147 	/*
148 	 * Throw out ranges that are too far apart (controlled by
149 	 * MAX_GAP).
150 	 */
151 
152 	for (i = 1; i < npmem_ranges; i++) {
153 		if (pmem_ranges[i].start_pfn -
154 			(pmem_ranges[i-1].start_pfn +
155 			 pmem_ranges[i-1].pages) > MAX_GAP) {
156 			npmem_ranges = i;
157 			printk("Large gap in memory detected (%ld pages). "
158 			       "Consider turning on CONFIG_DISCONTIGMEM\n",
159 			       pmem_ranges[i].start_pfn -
160 			       (pmem_ranges[i-1].start_pfn +
161 			        pmem_ranges[i-1].pages));
162 			break;
163 		}
164 	}
165 #endif
166 
167 	if (npmem_ranges > 1) {
168 
169 		/* Print the memory ranges */
170 
171 		printk(KERN_INFO "Memory Ranges:\n");
172 
173 		for (i = 0; i < npmem_ranges; i++) {
174 			unsigned long start;
175 			unsigned long size;
176 
177 			size = (pmem_ranges[i].pages << PAGE_SHIFT);
178 			start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
179 			printk(KERN_INFO "%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
180 				i,start, start + (size - 1), size >> 20);
181 		}
182 	}
183 
184 	sysram_resource_count = npmem_ranges;
185 	for (i = 0; i < sysram_resource_count; i++) {
186 		struct resource *res = &sysram_resources[i];
187 		res->name = "System RAM";
188 		res->start = pmem_ranges[i].start_pfn << PAGE_SHIFT;
189 		res->end = res->start + (pmem_ranges[i].pages << PAGE_SHIFT)-1;
190 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
191 		request_resource(&iomem_resource, res);
192 	}
193 
194 	/*
195 	 * For 32 bit kernels we limit the amount of memory we can
196 	 * support, in order to preserve enough kernel address space
197 	 * for other purposes. For 64 bit kernels we don't normally
198 	 * limit the memory, but this mechanism can be used to
199 	 * artificially limit the amount of memory (and it is written
200 	 * to work with multiple memory ranges).
201 	 */
202 
203 	mem_limit_func();       /* check for "mem=" argument */
204 
205 	mem_max = 0;
206 	num_physpages = 0;
207 	for (i = 0; i < npmem_ranges; i++) {
208 		unsigned long rsize;
209 
210 		rsize = pmem_ranges[i].pages << PAGE_SHIFT;
211 		if ((mem_max + rsize) > mem_limit) {
212 			printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
213 			if (mem_max == mem_limit)
214 				npmem_ranges = i;
215 			else {
216 				pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
217 						       - (mem_max >> PAGE_SHIFT);
218 				npmem_ranges = i + 1;
219 				mem_max = mem_limit;
220 			}
221 	        num_physpages += pmem_ranges[i].pages;
222 			break;
223 		}
224 	    num_physpages += pmem_ranges[i].pages;
225 		mem_max += rsize;
226 	}
227 
228 	printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
229 
230 #ifndef CONFIG_DISCONTIGMEM
231 	/* Merge the ranges, keeping track of the holes */
232 
233 	{
234 		unsigned long end_pfn;
235 		unsigned long hole_pages;
236 
237 		npmem_holes = 0;
238 		end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
239 		for (i = 1; i < npmem_ranges; i++) {
240 
241 			hole_pages = pmem_ranges[i].start_pfn - end_pfn;
242 			if (hole_pages) {
243 				pmem_holes[npmem_holes].start_pfn = end_pfn;
244 				pmem_holes[npmem_holes++].pages = hole_pages;
245 				end_pfn += hole_pages;
246 			}
247 			end_pfn += pmem_ranges[i].pages;
248 		}
249 
250 		pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
251 		npmem_ranges = 1;
252 	}
253 #endif
254 
255 	bootmap_pages = 0;
256 	for (i = 0; i < npmem_ranges; i++)
257 		bootmap_pages += bootmem_bootmap_pages(pmem_ranges[i].pages);
258 
259 	bootmap_start_pfn = PAGE_ALIGN(__pa((unsigned long) &_end)) >> PAGE_SHIFT;
260 
261 #ifdef CONFIG_DISCONTIGMEM
262 	for (i = 0; i < MAX_PHYSMEM_RANGES; i++) {
263 		memset(NODE_DATA(i), 0, sizeof(pg_data_t));
264 		NODE_DATA(i)->bdata = &bootmem_node_data[i];
265 	}
266 	memset(pfnnid_map, 0xff, sizeof(pfnnid_map));
267 
268 	for (i = 0; i < npmem_ranges; i++)
269 		node_set_online(i);
270 #endif
271 
272 	/*
273 	 * Initialize and free the full range of memory in each range.
274 	 * Note that the only writing these routines do are to the bootmap,
275 	 * and we've made sure to locate the bootmap properly so that they
276 	 * won't be writing over anything important.
277 	 */
278 
279 	bootmap_pfn = bootmap_start_pfn;
280 	max_pfn = 0;
281 	for (i = 0; i < npmem_ranges; i++) {
282 		unsigned long start_pfn;
283 		unsigned long npages;
284 
285 		start_pfn = pmem_ranges[i].start_pfn;
286 		npages = pmem_ranges[i].pages;
287 
288 		bootmap_size = init_bootmem_node(NODE_DATA(i),
289 						bootmap_pfn,
290 						start_pfn,
291 						(start_pfn + npages) );
292 		free_bootmem_node(NODE_DATA(i),
293 				  (start_pfn << PAGE_SHIFT),
294 				  (npages << PAGE_SHIFT) );
295 		bootmap_pfn += (bootmap_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
296 		if ((start_pfn + npages) > max_pfn)
297 			max_pfn = start_pfn + npages;
298 	}
299 
300 	/* IOMMU is always used to access "high mem" on those boxes
301 	 * that can support enough mem that a PCI device couldn't
302 	 * directly DMA to any physical addresses.
303 	 * ISA DMA support will need to revisit this.
304 	 */
305 	max_low_pfn = max_pfn;
306 
307 	if ((bootmap_pfn - bootmap_start_pfn) != bootmap_pages) {
308 		printk(KERN_WARNING "WARNING! bootmap sizing is messed up!\n");
309 		BUG();
310 	}
311 
312 	/* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
313 
314 #define PDC_CONSOLE_IO_IODC_SIZE 32768
315 
316 	reserve_bootmem_node(NODE_DATA(0), 0UL,
317 			(unsigned long)(PAGE0->mem_free +
318 				PDC_CONSOLE_IO_IODC_SIZE), BOOTMEM_DEFAULT);
319 	reserve_bootmem_node(NODE_DATA(0), __pa((unsigned long)_text),
320 			(unsigned long)(_end - _text), BOOTMEM_DEFAULT);
321 	reserve_bootmem_node(NODE_DATA(0), (bootmap_start_pfn << PAGE_SHIFT),
322 			((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT),
323 			BOOTMEM_DEFAULT);
324 
325 #ifndef CONFIG_DISCONTIGMEM
326 
327 	/* reserve the holes */
328 
329 	for (i = 0; i < npmem_holes; i++) {
330 		reserve_bootmem_node(NODE_DATA(0),
331 				(pmem_holes[i].start_pfn << PAGE_SHIFT),
332 				(pmem_holes[i].pages << PAGE_SHIFT),
333 				BOOTMEM_DEFAULT);
334 	}
335 #endif
336 
337 #ifdef CONFIG_BLK_DEV_INITRD
338 	if (initrd_start) {
339 		printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
340 		if (__pa(initrd_start) < mem_max) {
341 			unsigned long initrd_reserve;
342 
343 			if (__pa(initrd_end) > mem_max) {
344 				initrd_reserve = mem_max - __pa(initrd_start);
345 			} else {
346 				initrd_reserve = initrd_end - initrd_start;
347 			}
348 			initrd_below_start_ok = 1;
349 			printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
350 
351 			reserve_bootmem_node(NODE_DATA(0), __pa(initrd_start),
352 					initrd_reserve, BOOTMEM_DEFAULT);
353 		}
354 	}
355 #endif
356 
357 	data_resource.start =  virt_to_phys(&data_start);
358 	data_resource.end = virt_to_phys(_end) - 1;
359 	code_resource.start = virt_to_phys(_text);
360 	code_resource.end = virt_to_phys(&data_start)-1;
361 
362 	/* We don't know which region the kernel will be in, so try
363 	 * all of them.
364 	 */
365 	for (i = 0; i < sysram_resource_count; i++) {
366 		struct resource *res = &sysram_resources[i];
367 		request_resource(res, &code_resource);
368 		request_resource(res, &data_resource);
369 	}
370 	request_resource(&sysram_resources[0], &pdcdata_resource);
371 }
372 
373 void free_initmem(void)
374 {
375 	unsigned long addr, init_begin, init_end;
376 
377 	printk(KERN_INFO "Freeing unused kernel memory: ");
378 
379 #ifdef CONFIG_DEBUG_KERNEL
380 	/* Attempt to catch anyone trying to execute code here
381 	 * by filling the page with BRK insns.
382 	 *
383 	 * If we disable interrupts for all CPUs, then IPI stops working.
384 	 * Kinda breaks the global cache flushing.
385 	 */
386 	local_irq_disable();
387 
388 	memset(__init_begin, 0x00,
389 		(unsigned long)__init_end - (unsigned long)__init_begin);
390 
391 	flush_data_cache();
392 	asm volatile("sync" : : );
393 	flush_icache_range((unsigned long)__init_begin, (unsigned long)__init_end);
394 	asm volatile("sync" : : );
395 
396 	local_irq_enable();
397 #endif
398 
399 	/* align __init_begin and __init_end to page size,
400 	   ignoring linker script where we might have tried to save RAM */
401 	init_begin = PAGE_ALIGN((unsigned long)(__init_begin));
402 	init_end   = PAGE_ALIGN((unsigned long)(__init_end));
403 	for (addr = init_begin; addr < init_end; addr += PAGE_SIZE) {
404 		ClearPageReserved(virt_to_page(addr));
405 		init_page_count(virt_to_page(addr));
406 		free_page(addr);
407 		num_physpages++;
408 		totalram_pages++;
409 	}
410 
411 	/* set up a new led state on systems shipped LED State panel */
412 	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
413 
414 	printk("%luk freed\n", (init_end - init_begin) >> 10);
415 }
416 
417 
418 #ifdef CONFIG_DEBUG_RODATA
419 void mark_rodata_ro(void)
420 {
421 	/* rodata memory was already mapped with KERNEL_RO access rights by
422            pagetable_init() and map_pages(). No need to do additional stuff here */
423 	printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
424 		(unsigned long)(__end_rodata - __start_rodata) >> 10);
425 }
426 #endif
427 
428 
429 /*
430  * Just an arbitrary offset to serve as a "hole" between mapping areas
431  * (between top of physical memory and a potential pcxl dma mapping
432  * area, and below the vmalloc mapping area).
433  *
434  * The current 32K value just means that there will be a 32K "hole"
435  * between mapping areas. That means that  any out-of-bounds memory
436  * accesses will hopefully be caught. The vmalloc() routines leaves
437  * a hole of 4kB between each vmalloced area for the same reason.
438  */
439 
440  /* Leave room for gateway page expansion */
441 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
442 #error KERNEL_MAP_START is in gateway reserved region
443 #endif
444 #define MAP_START (KERNEL_MAP_START)
445 
446 #define VM_MAP_OFFSET  (32*1024)
447 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
448 				     & ~(VM_MAP_OFFSET-1)))
449 
450 void *vmalloc_start __read_mostly;
451 EXPORT_SYMBOL(vmalloc_start);
452 
453 #ifdef CONFIG_PA11
454 unsigned long pcxl_dma_start __read_mostly;
455 #endif
456 
457 void __init mem_init(void)
458 {
459 	int codesize, reservedpages, datasize, initsize;
460 
461 	high_memory = __va((max_pfn << PAGE_SHIFT));
462 
463 #ifndef CONFIG_DISCONTIGMEM
464 	max_mapnr = page_to_pfn(virt_to_page(high_memory - 1)) + 1;
465 	totalram_pages += free_all_bootmem();
466 #else
467 	{
468 		int i;
469 
470 		for (i = 0; i < npmem_ranges; i++)
471 			totalram_pages += free_all_bootmem_node(NODE_DATA(i));
472 	}
473 #endif
474 
475 	codesize = (unsigned long)_etext - (unsigned long)_text;
476 	datasize = (unsigned long)_edata - (unsigned long)_etext;
477 	initsize = (unsigned long)__init_end - (unsigned long)__init_begin;
478 
479 	reservedpages = 0;
480 {
481 	unsigned long pfn;
482 #ifdef CONFIG_DISCONTIGMEM
483 	int i;
484 
485 	for (i = 0; i < npmem_ranges; i++) {
486 		for (pfn = node_start_pfn(i); pfn < node_end_pfn(i); pfn++) {
487 			if (PageReserved(pfn_to_page(pfn)))
488 				reservedpages++;
489 		}
490 	}
491 #else /* !CONFIG_DISCONTIGMEM */
492 	for (pfn = 0; pfn < max_pfn; pfn++) {
493 		/*
494 		 * Only count reserved RAM pages
495 		 */
496 		if (PageReserved(pfn_to_page(pfn)))
497 			reservedpages++;
498 	}
499 #endif
500 }
501 
502 #ifdef CONFIG_PA11
503 	if (hppa_dma_ops == &pcxl_dma_ops) {
504 		pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
505 		vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE);
506 	} else {
507 		pcxl_dma_start = 0;
508 		vmalloc_start = SET_MAP_OFFSET(MAP_START);
509 	}
510 #else
511 	vmalloc_start = SET_MAP_OFFSET(MAP_START);
512 #endif
513 
514 	printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n",
515 		(unsigned long)nr_free_pages() << (PAGE_SHIFT-10),
516 		num_physpages << (PAGE_SHIFT-10),
517 		codesize >> 10,
518 		reservedpages << (PAGE_SHIFT-10),
519 		datasize >> 10,
520 		initsize >> 10
521 	);
522 
523 #ifdef CONFIG_DEBUG_KERNEL /* double-sanity-check paranoia */
524 	printk("virtual kernel memory layout:\n"
525 	       "    vmalloc : 0x%p - 0x%p   (%4ld MB)\n"
526 	       "    memory  : 0x%p - 0x%p   (%4ld MB)\n"
527 	       "      .init : 0x%p - 0x%p   (%4ld kB)\n"
528 	       "      .data : 0x%p - 0x%p   (%4ld kB)\n"
529 	       "      .text : 0x%p - 0x%p   (%4ld kB)\n",
530 
531 	       (void*)VMALLOC_START, (void*)VMALLOC_END,
532 	       (VMALLOC_END - VMALLOC_START) >> 20,
533 
534 	       __va(0), high_memory,
535 	       ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
536 
537 	       __init_begin, __init_end,
538 	       ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
539 
540 	       _etext, _edata,
541 	       ((unsigned long)_edata - (unsigned long)_etext) >> 10,
542 
543 	       _text, _etext,
544 	       ((unsigned long)_etext - (unsigned long)_text) >> 10);
545 #endif
546 }
547 
548 unsigned long *empty_zero_page __read_mostly;
549 EXPORT_SYMBOL(empty_zero_page);
550 
551 void show_mem(void)
552 {
553 	int i,free = 0,total = 0,reserved = 0;
554 	int shared = 0, cached = 0;
555 
556 	printk(KERN_INFO "Mem-info:\n");
557 	show_free_areas();
558 #ifndef CONFIG_DISCONTIGMEM
559 	i = max_mapnr;
560 	while (i-- > 0) {
561 		total++;
562 		if (PageReserved(mem_map+i))
563 			reserved++;
564 		else if (PageSwapCache(mem_map+i))
565 			cached++;
566 		else if (!page_count(&mem_map[i]))
567 			free++;
568 		else
569 			shared += page_count(&mem_map[i]) - 1;
570 	}
571 #else
572 	for (i = 0; i < npmem_ranges; i++) {
573 		int j;
574 
575 		for (j = node_start_pfn(i); j < node_end_pfn(i); j++) {
576 			struct page *p;
577 			unsigned long flags;
578 
579 			pgdat_resize_lock(NODE_DATA(i), &flags);
580 			p = nid_page_nr(i, j) - node_start_pfn(i);
581 
582 			total++;
583 			if (PageReserved(p))
584 				reserved++;
585 			else if (PageSwapCache(p))
586 				cached++;
587 			else if (!page_count(p))
588 				free++;
589 			else
590 				shared += page_count(p) - 1;
591 			pgdat_resize_unlock(NODE_DATA(i), &flags);
592         	}
593 	}
594 #endif
595 	printk(KERN_INFO "%d pages of RAM\n", total);
596 	printk(KERN_INFO "%d reserved pages\n", reserved);
597 	printk(KERN_INFO "%d pages shared\n", shared);
598 	printk(KERN_INFO "%d pages swap cached\n", cached);
599 
600 
601 #ifdef CONFIG_DISCONTIGMEM
602 	{
603 		struct zonelist *zl;
604 		int i, j;
605 
606 		for (i = 0; i < npmem_ranges; i++) {
607 			zl = node_zonelist(i, 0);
608 			for (j = 0; j < MAX_NR_ZONES; j++) {
609 				struct zoneref *z;
610 				struct zone *zone;
611 
612 				printk("Zone list for zone %d on node %d: ", j, i);
613 				for_each_zone_zonelist(zone, z, zl, j)
614 					printk("[%d/%s] ", zone_to_nid(zone),
615 								zone->name);
616 				printk("\n");
617 			}
618 		}
619 	}
620 #endif
621 }
622 
623 
624 static void __init map_pages(unsigned long start_vaddr, unsigned long start_paddr, unsigned long size, pgprot_t pgprot)
625 {
626 	pgd_t *pg_dir;
627 	pmd_t *pmd;
628 	pte_t *pg_table;
629 	unsigned long end_paddr;
630 	unsigned long start_pmd;
631 	unsigned long start_pte;
632 	unsigned long tmp1;
633 	unsigned long tmp2;
634 	unsigned long address;
635 	unsigned long ro_start;
636 	unsigned long ro_end;
637 	unsigned long fv_addr;
638 	unsigned long gw_addr;
639 	extern const unsigned long fault_vector_20;
640 	extern void * const linux_gateway_page;
641 
642 	ro_start = __pa((unsigned long)_text);
643 	ro_end   = __pa((unsigned long)&data_start);
644 	fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
645 	gw_addr  = __pa((unsigned long)&linux_gateway_page) & PAGE_MASK;
646 
647 	end_paddr = start_paddr + size;
648 
649 	pg_dir = pgd_offset_k(start_vaddr);
650 
651 #if PTRS_PER_PMD == 1
652 	start_pmd = 0;
653 #else
654 	start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
655 #endif
656 	start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
657 
658 	address = start_paddr;
659 	while (address < end_paddr) {
660 #if PTRS_PER_PMD == 1
661 		pmd = (pmd_t *)__pa(pg_dir);
662 #else
663 		pmd = (pmd_t *)pgd_address(*pg_dir);
664 
665 		/*
666 		 * pmd is physical at this point
667 		 */
668 
669 		if (!pmd) {
670 			pmd = (pmd_t *) alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE << PMD_ORDER);
671 			pmd = (pmd_t *) __pa(pmd);
672 		}
673 
674 		pgd_populate(NULL, pg_dir, __va(pmd));
675 #endif
676 		pg_dir++;
677 
678 		/* now change pmd to kernel virtual addresses */
679 
680 		pmd = (pmd_t *)__va(pmd) + start_pmd;
681 		for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++,pmd++) {
682 
683 			/*
684 			 * pg_table is physical at this point
685 			 */
686 
687 			pg_table = (pte_t *)pmd_address(*pmd);
688 			if (!pg_table) {
689 				pg_table = (pte_t *)
690 					alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE);
691 				pg_table = (pte_t *) __pa(pg_table);
692 			}
693 
694 			pmd_populate_kernel(NULL, pmd, __va(pg_table));
695 
696 			/* now change pg_table to kernel virtual addresses */
697 
698 			pg_table = (pte_t *) __va(pg_table) + start_pte;
699 			for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++,pg_table++) {
700 				pte_t pte;
701 
702 				/*
703 				 * Map the fault vector writable so we can
704 				 * write the HPMC checksum.
705 				 */
706 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
707 				if (address >= ro_start && address < ro_end
708 							&& address != fv_addr
709 							&& address != gw_addr)
710 				    pte = __mk_pte(address, PAGE_KERNEL_RO);
711 				else
712 #endif
713 				    pte = __mk_pte(address, pgprot);
714 
715 				if (address >= end_paddr)
716 					pte_val(pte) = 0;
717 
718 				set_pte(pg_table, pte);
719 
720 				address += PAGE_SIZE;
721 			}
722 			start_pte = 0;
723 
724 			if (address >= end_paddr)
725 			    break;
726 		}
727 		start_pmd = 0;
728 	}
729 }
730 
731 /*
732  * pagetable_init() sets up the page tables
733  *
734  * Note that gateway_init() places the Linux gateway page at page 0.
735  * Since gateway pages cannot be dereferenced this has the desirable
736  * side effect of trapping those pesky NULL-reference errors in the
737  * kernel.
738  */
739 static void __init pagetable_init(void)
740 {
741 	int range;
742 
743 	/* Map each physical memory range to its kernel vaddr */
744 
745 	for (range = 0; range < npmem_ranges; range++) {
746 		unsigned long start_paddr;
747 		unsigned long end_paddr;
748 		unsigned long size;
749 
750 		start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
751 		end_paddr = start_paddr + (pmem_ranges[range].pages << PAGE_SHIFT);
752 		size = pmem_ranges[range].pages << PAGE_SHIFT;
753 
754 		map_pages((unsigned long)__va(start_paddr), start_paddr,
755 			size, PAGE_KERNEL);
756 	}
757 
758 #ifdef CONFIG_BLK_DEV_INITRD
759 	if (initrd_end && initrd_end > mem_limit) {
760 		printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
761 		map_pages(initrd_start, __pa(initrd_start),
762 			initrd_end - initrd_start, PAGE_KERNEL);
763 	}
764 #endif
765 
766 	empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
767 	memset(empty_zero_page, 0, PAGE_SIZE);
768 }
769 
770 static void __init gateway_init(void)
771 {
772 	unsigned long linux_gateway_page_addr;
773 	/* FIXME: This is 'const' in order to trick the compiler
774 	   into not treating it as DP-relative data. */
775 	extern void * const linux_gateway_page;
776 
777 	linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
778 
779 	/*
780 	 * Setup Linux Gateway page.
781 	 *
782 	 * The Linux gateway page will reside in kernel space (on virtual
783 	 * page 0), so it doesn't need to be aliased into user space.
784 	 */
785 
786 	map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
787 		PAGE_SIZE, PAGE_GATEWAY);
788 }
789 
790 #ifdef CONFIG_HPUX
791 void
792 map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm)
793 {
794 	pgd_t *pg_dir;
795 	pmd_t *pmd;
796 	pte_t *pg_table;
797 	unsigned long start_pmd;
798 	unsigned long start_pte;
799 	unsigned long address;
800 	unsigned long hpux_gw_page_addr;
801 	/* FIXME: This is 'const' in order to trick the compiler
802 	   into not treating it as DP-relative data. */
803 	extern void * const hpux_gateway_page;
804 
805 	hpux_gw_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
806 
807 	/*
808 	 * Setup HP-UX Gateway page.
809 	 *
810 	 * The HP-UX gateway page resides in the user address space,
811 	 * so it needs to be aliased into each process.
812 	 */
813 
814 	pg_dir = pgd_offset(mm,hpux_gw_page_addr);
815 
816 #if PTRS_PER_PMD == 1
817 	start_pmd = 0;
818 #else
819 	start_pmd = ((hpux_gw_page_addr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
820 #endif
821 	start_pte = ((hpux_gw_page_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
822 
823 	address = __pa(&hpux_gateway_page);
824 #if PTRS_PER_PMD == 1
825 	pmd = (pmd_t *)__pa(pg_dir);
826 #else
827 	pmd = (pmd_t *) pgd_address(*pg_dir);
828 
829 	/*
830 	 * pmd is physical at this point
831 	 */
832 
833 	if (!pmd) {
834 		pmd = (pmd_t *) get_zeroed_page(GFP_KERNEL);
835 		pmd = (pmd_t *) __pa(pmd);
836 	}
837 
838 	__pgd_val_set(*pg_dir, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pmd);
839 #endif
840 	/* now change pmd to kernel virtual addresses */
841 
842 	pmd = (pmd_t *)__va(pmd) + start_pmd;
843 
844 	/*
845 	 * pg_table is physical at this point
846 	 */
847 
848 	pg_table = (pte_t *) pmd_address(*pmd);
849 	if (!pg_table)
850 		pg_table = (pte_t *) __pa(get_zeroed_page(GFP_KERNEL));
851 
852 	__pmd_val_set(*pmd, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pg_table);
853 
854 	/* now change pg_table to kernel virtual addresses */
855 
856 	pg_table = (pte_t *) __va(pg_table) + start_pte;
857 	set_pte(pg_table, __mk_pte(address, PAGE_GATEWAY));
858 }
859 EXPORT_SYMBOL(map_hpux_gateway_page);
860 #endif
861 
862 void __init paging_init(void)
863 {
864 	int i;
865 
866 	setup_bootmem();
867 	pagetable_init();
868 	gateway_init();
869 	flush_cache_all_local(); /* start with known state */
870 	flush_tlb_all_local(NULL);
871 
872 	for (i = 0; i < npmem_ranges; i++) {
873 		unsigned long zones_size[MAX_NR_ZONES] = { 0, };
874 
875 		zones_size[ZONE_NORMAL] = pmem_ranges[i].pages;
876 
877 #ifdef CONFIG_DISCONTIGMEM
878 		/* Need to initialize the pfnnid_map before we can initialize
879 		   the zone */
880 		{
881 		    int j;
882 		    for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
883 			 j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
884 			 j++) {
885 			pfnnid_map[j] = i;
886 		    }
887 		}
888 #endif
889 
890 		free_area_init_node(i, zones_size,
891 				pmem_ranges[i].start_pfn, NULL);
892 	}
893 }
894 
895 #ifdef CONFIG_PA20
896 
897 /*
898  * Currently, all PA20 chips have 18 bit protection IDs, which is the
899  * limiting factor (space ids are 32 bits).
900  */
901 
902 #define NR_SPACE_IDS 262144
903 
904 #else
905 
906 /*
907  * Currently we have a one-to-one relationship between space IDs and
908  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
909  * support 15 bit protection IDs, so that is the limiting factor.
910  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
911  * probably not worth the effort for a special case here.
912  */
913 
914 #define NR_SPACE_IDS 32768
915 
916 #endif  /* !CONFIG_PA20 */
917 
918 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
919 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
920 
921 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
922 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
923 static unsigned long space_id_index;
924 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
925 static unsigned long dirty_space_ids = 0;
926 
927 static DEFINE_SPINLOCK(sid_lock);
928 
929 unsigned long alloc_sid(void)
930 {
931 	unsigned long index;
932 
933 	spin_lock(&sid_lock);
934 
935 	if (free_space_ids == 0) {
936 		if (dirty_space_ids != 0) {
937 			spin_unlock(&sid_lock);
938 			flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
939 			spin_lock(&sid_lock);
940 		}
941 		BUG_ON(free_space_ids == 0);
942 	}
943 
944 	free_space_ids--;
945 
946 	index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
947 	space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
948 	space_id_index = index;
949 
950 	spin_unlock(&sid_lock);
951 
952 	return index << SPACEID_SHIFT;
953 }
954 
955 void free_sid(unsigned long spaceid)
956 {
957 	unsigned long index = spaceid >> SPACEID_SHIFT;
958 	unsigned long *dirty_space_offset;
959 
960 	dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
961 	index &= (BITS_PER_LONG - 1);
962 
963 	spin_lock(&sid_lock);
964 
965 	BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
966 
967 	*dirty_space_offset |= (1L << index);
968 	dirty_space_ids++;
969 
970 	spin_unlock(&sid_lock);
971 }
972 
973 
974 #ifdef CONFIG_SMP
975 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
976 {
977 	int i;
978 
979 	/* NOTE: sid_lock must be held upon entry */
980 
981 	*ndirtyptr = dirty_space_ids;
982 	if (dirty_space_ids != 0) {
983 	    for (i = 0; i < SID_ARRAY_SIZE; i++) {
984 		dirty_array[i] = dirty_space_id[i];
985 		dirty_space_id[i] = 0;
986 	    }
987 	    dirty_space_ids = 0;
988 	}
989 
990 	return;
991 }
992 
993 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
994 {
995 	int i;
996 
997 	/* NOTE: sid_lock must be held upon entry */
998 
999 	if (ndirty != 0) {
1000 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
1001 			space_id[i] ^= dirty_array[i];
1002 		}
1003 
1004 		free_space_ids += ndirty;
1005 		space_id_index = 0;
1006 	}
1007 }
1008 
1009 #else /* CONFIG_SMP */
1010 
1011 static void recycle_sids(void)
1012 {
1013 	int i;
1014 
1015 	/* NOTE: sid_lock must be held upon entry */
1016 
1017 	if (dirty_space_ids != 0) {
1018 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
1019 			space_id[i] ^= dirty_space_id[i];
1020 			dirty_space_id[i] = 0;
1021 		}
1022 
1023 		free_space_ids += dirty_space_ids;
1024 		dirty_space_ids = 0;
1025 		space_id_index = 0;
1026 	}
1027 }
1028 #endif
1029 
1030 /*
1031  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
1032  * purged, we can safely reuse the space ids that were released but
1033  * not flushed from the tlb.
1034  */
1035 
1036 #ifdef CONFIG_SMP
1037 
1038 static unsigned long recycle_ndirty;
1039 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
1040 static unsigned int recycle_inuse;
1041 
1042 void flush_tlb_all(void)
1043 {
1044 	int do_recycle;
1045 
1046 	do_recycle = 0;
1047 	spin_lock(&sid_lock);
1048 	if (dirty_space_ids > RECYCLE_THRESHOLD) {
1049 	    BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
1050 	    get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
1051 	    recycle_inuse++;
1052 	    do_recycle++;
1053 	}
1054 	spin_unlock(&sid_lock);
1055 	on_each_cpu(flush_tlb_all_local, NULL, 1);
1056 	if (do_recycle) {
1057 	    spin_lock(&sid_lock);
1058 	    recycle_sids(recycle_ndirty,recycle_dirty_array);
1059 	    recycle_inuse = 0;
1060 	    spin_unlock(&sid_lock);
1061 	}
1062 }
1063 #else
1064 void flush_tlb_all(void)
1065 {
1066 	spin_lock(&sid_lock);
1067 	flush_tlb_all_local(NULL);
1068 	recycle_sids();
1069 	spin_unlock(&sid_lock);
1070 }
1071 #endif
1072 
1073 #ifdef CONFIG_BLK_DEV_INITRD
1074 void free_initrd_mem(unsigned long start, unsigned long end)
1075 {
1076 	if (start >= end)
1077 		return;
1078 	printk(KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
1079 	for (; start < end; start += PAGE_SIZE) {
1080 		ClearPageReserved(virt_to_page(start));
1081 		init_page_count(virt_to_page(start));
1082 		free_page(start);
1083 		num_physpages++;
1084 		totalram_pages++;
1085 	}
1086 }
1087 #endif
1088