xref: /openbmc/linux/arch/parisc/mm/init.c (revision 87c2ce3b)
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  *
10  */
11 
12 #include <linux/config.h>
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/tlb.h>
28 #include <asm/pdc_chassis.h>
29 #include <asm/mmzone.h>
30 
31 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
32 
33 extern char _text;	/* start of kernel code, defined by linker */
34 extern int  data_start;
35 extern char _end;	/* end of BSS, defined by linker */
36 extern char __init_begin, __init_end;
37 
38 #ifdef CONFIG_DISCONTIGMEM
39 struct node_map_data node_data[MAX_NUMNODES];
40 bootmem_data_t bmem_data[MAX_NUMNODES];
41 unsigned char pfnnid_map[PFNNID_MAP_MAX];
42 #endif
43 
44 static struct resource data_resource = {
45 	.name	= "Kernel data",
46 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
47 };
48 
49 static struct resource code_resource = {
50 	.name	= "Kernel code",
51 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
52 };
53 
54 static struct resource pdcdata_resource = {
55 	.name	= "PDC data (Page Zero)",
56 	.start	= 0,
57 	.end	= 0x9ff,
58 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
59 };
60 
61 static struct resource sysram_resources[MAX_PHYSMEM_RANGES];
62 
63 /* The following array is initialized from the firmware specific
64  * information retrieved in kernel/inventory.c.
65  */
66 
67 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES];
68 int npmem_ranges;
69 
70 #ifdef __LP64__
71 #define MAX_MEM         (~0UL)
72 #else /* !__LP64__ */
73 #define MAX_MEM         (3584U*1024U*1024U)
74 #endif /* !__LP64__ */
75 
76 static unsigned long mem_limit = MAX_MEM;
77 
78 static void __init mem_limit_func(void)
79 {
80 	char *cp, *end;
81 	unsigned long limit;
82 	extern char saved_command_line[];
83 
84 	/* We need this before __setup() functions are called */
85 
86 	limit = MAX_MEM;
87 	for (cp = saved_command_line; *cp; ) {
88 		if (memcmp(cp, "mem=", 4) == 0) {
89 			cp += 4;
90 			limit = memparse(cp, &end);
91 			if (end != cp)
92 				break;
93 			cp = end;
94 		} else {
95 			while (*cp != ' ' && *cp)
96 				++cp;
97 			while (*cp == ' ')
98 				++cp;
99 		}
100 	}
101 
102 	if (limit < mem_limit)
103 		mem_limit = limit;
104 }
105 
106 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
107 
108 static void __init setup_bootmem(void)
109 {
110 	unsigned long bootmap_size;
111 	unsigned long mem_max;
112 	unsigned long bootmap_pages;
113 	unsigned long bootmap_start_pfn;
114 	unsigned long bootmap_pfn;
115 #ifndef CONFIG_DISCONTIGMEM
116 	physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
117 	int npmem_holes;
118 #endif
119 	int i, sysram_resource_count;
120 
121 	disable_sr_hashing(); /* Turn off space register hashing */
122 
123 	/*
124 	 * Sort the ranges. Since the number of ranges is typically
125 	 * small, and performance is not an issue here, just do
126 	 * a simple insertion sort.
127 	 */
128 
129 	for (i = 1; i < npmem_ranges; i++) {
130 		int j;
131 
132 		for (j = i; j > 0; j--) {
133 			unsigned long tmp;
134 
135 			if (pmem_ranges[j-1].start_pfn <
136 			    pmem_ranges[j].start_pfn) {
137 
138 				break;
139 			}
140 			tmp = pmem_ranges[j-1].start_pfn;
141 			pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn;
142 			pmem_ranges[j].start_pfn = tmp;
143 			tmp = pmem_ranges[j-1].pages;
144 			pmem_ranges[j-1].pages = pmem_ranges[j].pages;
145 			pmem_ranges[j].pages = tmp;
146 		}
147 	}
148 
149 #ifndef CONFIG_DISCONTIGMEM
150 	/*
151 	 * Throw out ranges that are too far apart (controlled by
152 	 * MAX_GAP).
153 	 */
154 
155 	for (i = 1; i < npmem_ranges; i++) {
156 		if (pmem_ranges[i].start_pfn -
157 			(pmem_ranges[i-1].start_pfn +
158 			 pmem_ranges[i-1].pages) > MAX_GAP) {
159 			npmem_ranges = i;
160 			printk("Large gap in memory detected (%ld pages). "
161 			       "Consider turning on CONFIG_DISCONTIGMEM\n",
162 			       pmem_ranges[i].start_pfn -
163 			       (pmem_ranges[i-1].start_pfn +
164 			        pmem_ranges[i-1].pages));
165 			break;
166 		}
167 	}
168 #endif
169 
170 	if (npmem_ranges > 1) {
171 
172 		/* Print the memory ranges */
173 
174 		printk(KERN_INFO "Memory Ranges:\n");
175 
176 		for (i = 0; i < npmem_ranges; i++) {
177 			unsigned long start;
178 			unsigned long size;
179 
180 			size = (pmem_ranges[i].pages << PAGE_SHIFT);
181 			start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
182 			printk(KERN_INFO "%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
183 				i,start, start + (size - 1), size >> 20);
184 		}
185 	}
186 
187 	sysram_resource_count = npmem_ranges;
188 	for (i = 0; i < sysram_resource_count; i++) {
189 		struct resource *res = &sysram_resources[i];
190 		res->name = "System RAM";
191 		res->start = pmem_ranges[i].start_pfn << PAGE_SHIFT;
192 		res->end = res->start + (pmem_ranges[i].pages << PAGE_SHIFT)-1;
193 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
194 		request_resource(&iomem_resource, res);
195 	}
196 
197 	/*
198 	 * For 32 bit kernels we limit the amount of memory we can
199 	 * support, in order to preserve enough kernel address space
200 	 * for other purposes. For 64 bit kernels we don't normally
201 	 * limit the memory, but this mechanism can be used to
202 	 * artificially limit the amount of memory (and it is written
203 	 * to work with multiple memory ranges).
204 	 */
205 
206 	mem_limit_func();       /* check for "mem=" argument */
207 
208 	mem_max = 0;
209 	num_physpages = 0;
210 	for (i = 0; i < npmem_ranges; i++) {
211 		unsigned long rsize;
212 
213 		rsize = pmem_ranges[i].pages << PAGE_SHIFT;
214 		if ((mem_max + rsize) > mem_limit) {
215 			printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
216 			if (mem_max == mem_limit)
217 				npmem_ranges = i;
218 			else {
219 				pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
220 						       - (mem_max >> PAGE_SHIFT);
221 				npmem_ranges = i + 1;
222 				mem_max = mem_limit;
223 			}
224 	        num_physpages += pmem_ranges[i].pages;
225 			break;
226 		}
227 	    num_physpages += pmem_ranges[i].pages;
228 		mem_max += rsize;
229 	}
230 
231 	printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
232 
233 #ifndef CONFIG_DISCONTIGMEM
234 	/* Merge the ranges, keeping track of the holes */
235 
236 	{
237 		unsigned long end_pfn;
238 		unsigned long hole_pages;
239 
240 		npmem_holes = 0;
241 		end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
242 		for (i = 1; i < npmem_ranges; i++) {
243 
244 			hole_pages = pmem_ranges[i].start_pfn - end_pfn;
245 			if (hole_pages) {
246 				pmem_holes[npmem_holes].start_pfn = end_pfn;
247 				pmem_holes[npmem_holes++].pages = hole_pages;
248 				end_pfn += hole_pages;
249 			}
250 			end_pfn += pmem_ranges[i].pages;
251 		}
252 
253 		pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
254 		npmem_ranges = 1;
255 	}
256 #endif
257 
258 	bootmap_pages = 0;
259 	for (i = 0; i < npmem_ranges; i++)
260 		bootmap_pages += bootmem_bootmap_pages(pmem_ranges[i].pages);
261 
262 	bootmap_start_pfn = PAGE_ALIGN(__pa((unsigned long) &_end)) >> PAGE_SHIFT;
263 
264 #ifdef CONFIG_DISCONTIGMEM
265 	for (i = 0; i < MAX_PHYSMEM_RANGES; i++) {
266 		memset(NODE_DATA(i), 0, sizeof(pg_data_t));
267 		NODE_DATA(i)->bdata = &bmem_data[i];
268 	}
269 	memset(pfnnid_map, 0xff, sizeof(pfnnid_map));
270 
271 	for (i = 0; i < npmem_ranges; i++)
272 		node_set_online(i);
273 #endif
274 
275 	/*
276 	 * Initialize and free the full range of memory in each range.
277 	 * Note that the only writing these routines do are to the bootmap,
278 	 * and we've made sure to locate the bootmap properly so that they
279 	 * won't be writing over anything important.
280 	 */
281 
282 	bootmap_pfn = bootmap_start_pfn;
283 	max_pfn = 0;
284 	for (i = 0; i < npmem_ranges; i++) {
285 		unsigned long start_pfn;
286 		unsigned long npages;
287 
288 		start_pfn = pmem_ranges[i].start_pfn;
289 		npages = pmem_ranges[i].pages;
290 
291 		bootmap_size = init_bootmem_node(NODE_DATA(i),
292 						bootmap_pfn,
293 						start_pfn,
294 						(start_pfn + npages) );
295 		free_bootmem_node(NODE_DATA(i),
296 				  (start_pfn << PAGE_SHIFT),
297 				  (npages << PAGE_SHIFT) );
298 		bootmap_pfn += (bootmap_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
299 		if ((start_pfn + npages) > max_pfn)
300 			max_pfn = start_pfn + npages;
301 	}
302 
303 	if ((bootmap_pfn - bootmap_start_pfn) != bootmap_pages) {
304 		printk(KERN_WARNING "WARNING! bootmap sizing is messed up!\n");
305 		BUG();
306 	}
307 
308 	/* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
309 
310 #define PDC_CONSOLE_IO_IODC_SIZE 32768
311 
312 	reserve_bootmem_node(NODE_DATA(0), 0UL,
313 			(unsigned long)(PAGE0->mem_free + PDC_CONSOLE_IO_IODC_SIZE));
314 	reserve_bootmem_node(NODE_DATA(0),__pa((unsigned long)&_text),
315 			(unsigned long)(&_end - &_text));
316 	reserve_bootmem_node(NODE_DATA(0), (bootmap_start_pfn << PAGE_SHIFT),
317 			((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT));
318 
319 #ifndef CONFIG_DISCONTIGMEM
320 
321 	/* reserve the holes */
322 
323 	for (i = 0; i < npmem_holes; i++) {
324 		reserve_bootmem_node(NODE_DATA(0),
325 				(pmem_holes[i].start_pfn << PAGE_SHIFT),
326 				(pmem_holes[i].pages << PAGE_SHIFT));
327 	}
328 #endif
329 
330 #ifdef CONFIG_BLK_DEV_INITRD
331 	if (initrd_start) {
332 		printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
333 		if (__pa(initrd_start) < mem_max) {
334 			unsigned long initrd_reserve;
335 
336 			if (__pa(initrd_end) > mem_max) {
337 				initrd_reserve = mem_max - __pa(initrd_start);
338 			} else {
339 				initrd_reserve = initrd_end - initrd_start;
340 			}
341 			initrd_below_start_ok = 1;
342 			printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
343 
344 			reserve_bootmem_node(NODE_DATA(0),__pa(initrd_start), initrd_reserve);
345 		}
346 	}
347 #endif
348 
349 	data_resource.start =  virt_to_phys(&data_start);
350 	data_resource.end = virt_to_phys(&_end)-1;
351 	code_resource.start = virt_to_phys(&_text);
352 	code_resource.end = virt_to_phys(&data_start)-1;
353 
354 	/* We don't know which region the kernel will be in, so try
355 	 * all of them.
356 	 */
357 	for (i = 0; i < sysram_resource_count; i++) {
358 		struct resource *res = &sysram_resources[i];
359 		request_resource(res, &code_resource);
360 		request_resource(res, &data_resource);
361 	}
362 	request_resource(&sysram_resources[0], &pdcdata_resource);
363 }
364 
365 void free_initmem(void)
366 {
367 	/* FIXME: */
368 #if 0
369 	printk(KERN_INFO "NOT FREEING INITMEM (%dk)\n",
370 			(&__init_end - &__init_begin) >> 10);
371 	return;
372 #else
373 	unsigned long addr;
374 
375 	printk(KERN_INFO "Freeing unused kernel memory: ");
376 
377 #if 1
378 	/* Attempt to catch anyone trying to execute code here
379 	 * by filling the page with BRK insns.
380 	 *
381 	 * If we disable interrupts for all CPUs, then IPI stops working.
382 	 * Kinda breaks the global cache flushing.
383 	 */
384 	local_irq_disable();
385 
386 	memset(&__init_begin, 0x00,
387 		(unsigned long)&__init_end - (unsigned long)&__init_begin);
388 
389 	flush_data_cache();
390 	asm volatile("sync" : : );
391 	flush_icache_range((unsigned long)&__init_begin, (unsigned long)&__init_end);
392 	asm volatile("sync" : : );
393 
394 	local_irq_enable();
395 #endif
396 
397 	addr = (unsigned long)(&__init_begin);
398 	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
399 		ClearPageReserved(virt_to_page(addr));
400 		set_page_count(virt_to_page(addr), 1);
401 		free_page(addr);
402 		num_physpages++;
403 		totalram_pages++;
404 	}
405 
406 	/* set up a new led state on systems shipped LED State panel */
407 	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
408 
409 	printk("%luk freed\n", (unsigned long)(&__init_end - &__init_begin) >> 10);
410 #endif
411 }
412 
413 /*
414  * Just an arbitrary offset to serve as a "hole" between mapping areas
415  * (between top of physical memory and a potential pcxl dma mapping
416  * area, and below the vmalloc mapping area).
417  *
418  * The current 32K value just means that there will be a 32K "hole"
419  * between mapping areas. That means that  any out-of-bounds memory
420  * accesses will hopefully be caught. The vmalloc() routines leaves
421  * a hole of 4kB between each vmalloced area for the same reason.
422  */
423 
424  /* Leave room for gateway page expansion */
425 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
426 #error KERNEL_MAP_START is in gateway reserved region
427 #endif
428 #define MAP_START (KERNEL_MAP_START)
429 
430 #define VM_MAP_OFFSET  (32*1024)
431 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
432 				     & ~(VM_MAP_OFFSET-1)))
433 
434 void *vmalloc_start;
435 EXPORT_SYMBOL(vmalloc_start);
436 
437 #ifdef CONFIG_PA11
438 unsigned long pcxl_dma_start;
439 #endif
440 
441 void __init mem_init(void)
442 {
443 	high_memory = __va((max_pfn << PAGE_SHIFT));
444 
445 #ifndef CONFIG_DISCONTIGMEM
446 	max_mapnr = page_to_pfn(virt_to_page(high_memory - 1)) + 1;
447 	totalram_pages += free_all_bootmem();
448 #else
449 	{
450 		int i;
451 
452 		for (i = 0; i < npmem_ranges; i++)
453 			totalram_pages += free_all_bootmem_node(NODE_DATA(i));
454 	}
455 #endif
456 
457 	printk(KERN_INFO "Memory: %luk available\n", num_physpages << (PAGE_SHIFT-10));
458 
459 #ifdef CONFIG_PA11
460 	if (hppa_dma_ops == &pcxl_dma_ops) {
461 		pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
462 		vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE);
463 	} else {
464 		pcxl_dma_start = 0;
465 		vmalloc_start = SET_MAP_OFFSET(MAP_START);
466 	}
467 #else
468 	vmalloc_start = SET_MAP_OFFSET(MAP_START);
469 #endif
470 
471 }
472 
473 int do_check_pgt_cache(int low, int high)
474 {
475 	return 0;
476 }
477 
478 unsigned long *empty_zero_page;
479 
480 void show_mem(void)
481 {
482 	int i,free = 0,total = 0,reserved = 0;
483 	int shared = 0, cached = 0;
484 
485 	printk(KERN_INFO "Mem-info:\n");
486 	show_free_areas();
487 	printk(KERN_INFO "Free swap:	 %6ldkB\n",
488 				nr_swap_pages<<(PAGE_SHIFT-10));
489 #ifndef CONFIG_DISCONTIGMEM
490 	i = max_mapnr;
491 	while (i-- > 0) {
492 		total++;
493 		if (PageReserved(mem_map+i))
494 			reserved++;
495 		else if (PageSwapCache(mem_map+i))
496 			cached++;
497 		else if (!page_count(&mem_map[i]))
498 			free++;
499 		else
500 			shared += page_count(&mem_map[i]) - 1;
501 	}
502 #else
503 	for (i = 0; i < npmem_ranges; i++) {
504 		int j;
505 
506 		for (j = node_start_pfn(i); j < node_end_pfn(i); j++) {
507 			struct page *p;
508 			unsigned long flags;
509 
510 			pgdat_resize_lock(NODE_DATA(i), &flags);
511 			p = nid_page_nr(i, j) - node_start_pfn(i);
512 
513 			total++;
514 			if (PageReserved(p))
515 				reserved++;
516 			else if (PageSwapCache(p))
517 				cached++;
518 			else if (!page_count(p))
519 				free++;
520 			else
521 				shared += page_count(p) - 1;
522 			pgdat_resize_unlock(NODE_DATA(i), &flags);
523         	}
524 	}
525 #endif
526 	printk(KERN_INFO "%d pages of RAM\n", total);
527 	printk(KERN_INFO "%d reserved pages\n", reserved);
528 	printk(KERN_INFO "%d pages shared\n", shared);
529 	printk(KERN_INFO "%d pages swap cached\n", cached);
530 
531 
532 #ifdef CONFIG_DISCONTIGMEM
533 	{
534 		struct zonelist *zl;
535 		int i, j, k;
536 
537 		for (i = 0; i < npmem_ranges; i++) {
538 			for (j = 0; j < MAX_NR_ZONES; j++) {
539 				zl = NODE_DATA(i)->node_zonelists + j;
540 
541 				printk("Zone list for zone %d on node %d: ", j, i);
542 				for (k = 0; zl->zones[k] != NULL; k++)
543 					printk("[%d/%s] ", zl->zones[k]->zone_pgdat->node_id, zl->zones[k]->name);
544 				printk("\n");
545 			}
546 		}
547 	}
548 #endif
549 }
550 
551 
552 static void __init map_pages(unsigned long start_vaddr, unsigned long start_paddr, unsigned long size, pgprot_t pgprot)
553 {
554 	pgd_t *pg_dir;
555 	pmd_t *pmd;
556 	pte_t *pg_table;
557 	unsigned long end_paddr;
558 	unsigned long start_pmd;
559 	unsigned long start_pte;
560 	unsigned long tmp1;
561 	unsigned long tmp2;
562 	unsigned long address;
563 	unsigned long ro_start;
564 	unsigned long ro_end;
565 	unsigned long fv_addr;
566 	unsigned long gw_addr;
567 	extern const unsigned long fault_vector_20;
568 	extern void * const linux_gateway_page;
569 
570 	ro_start = __pa((unsigned long)&_text);
571 	ro_end   = __pa((unsigned long)&data_start);
572 	fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
573 	gw_addr  = __pa((unsigned long)&linux_gateway_page) & PAGE_MASK;
574 
575 	end_paddr = start_paddr + size;
576 
577 	pg_dir = pgd_offset_k(start_vaddr);
578 
579 #if PTRS_PER_PMD == 1
580 	start_pmd = 0;
581 #else
582 	start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
583 #endif
584 	start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
585 
586 	address = start_paddr;
587 	while (address < end_paddr) {
588 #if PTRS_PER_PMD == 1
589 		pmd = (pmd_t *)__pa(pg_dir);
590 #else
591 		pmd = (pmd_t *)pgd_address(*pg_dir);
592 
593 		/*
594 		 * pmd is physical at this point
595 		 */
596 
597 		if (!pmd) {
598 			pmd = (pmd_t *) alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE << PMD_ORDER);
599 			pmd = (pmd_t *) __pa(pmd);
600 		}
601 
602 		pgd_populate(NULL, pg_dir, __va(pmd));
603 #endif
604 		pg_dir++;
605 
606 		/* now change pmd to kernel virtual addresses */
607 
608 		pmd = (pmd_t *)__va(pmd) + start_pmd;
609 		for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++,pmd++) {
610 
611 			/*
612 			 * pg_table is physical at this point
613 			 */
614 
615 			pg_table = (pte_t *)pmd_address(*pmd);
616 			if (!pg_table) {
617 				pg_table = (pte_t *)
618 					alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE);
619 				pg_table = (pte_t *) __pa(pg_table);
620 			}
621 
622 			pmd_populate_kernel(NULL, pmd, __va(pg_table));
623 
624 			/* now change pg_table to kernel virtual addresses */
625 
626 			pg_table = (pte_t *) __va(pg_table) + start_pte;
627 			for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++,pg_table++) {
628 				pte_t pte;
629 
630 				/*
631 				 * Map the fault vector writable so we can
632 				 * write the HPMC checksum.
633 				 */
634 				if (address >= ro_start && address < ro_end
635 							&& address != fv_addr
636 							&& address != gw_addr)
637 				    pte = __mk_pte(address, PAGE_KERNEL_RO);
638 				else
639 				    pte = __mk_pte(address, pgprot);
640 
641 				if (address >= end_paddr)
642 					pte_val(pte) = 0;
643 
644 				set_pte(pg_table, pte);
645 
646 				address += PAGE_SIZE;
647 			}
648 			start_pte = 0;
649 
650 			if (address >= end_paddr)
651 			    break;
652 		}
653 		start_pmd = 0;
654 	}
655 }
656 
657 /*
658  * pagetable_init() sets up the page tables
659  *
660  * Note that gateway_init() places the Linux gateway page at page 0.
661  * Since gateway pages cannot be dereferenced this has the desirable
662  * side effect of trapping those pesky NULL-reference errors in the
663  * kernel.
664  */
665 static void __init pagetable_init(void)
666 {
667 	int range;
668 
669 	/* Map each physical memory range to its kernel vaddr */
670 
671 	for (range = 0; range < npmem_ranges; range++) {
672 		unsigned long start_paddr;
673 		unsigned long end_paddr;
674 		unsigned long size;
675 
676 		start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
677 		end_paddr = start_paddr + (pmem_ranges[range].pages << PAGE_SHIFT);
678 		size = pmem_ranges[range].pages << PAGE_SHIFT;
679 
680 		map_pages((unsigned long)__va(start_paddr), start_paddr,
681 			size, PAGE_KERNEL);
682 	}
683 
684 #ifdef CONFIG_BLK_DEV_INITRD
685 	if (initrd_end && initrd_end > mem_limit) {
686 		printk("initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
687 		map_pages(initrd_start, __pa(initrd_start),
688 			initrd_end - initrd_start, PAGE_KERNEL);
689 	}
690 #endif
691 
692 	empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
693 	memset(empty_zero_page, 0, PAGE_SIZE);
694 }
695 
696 static void __init gateway_init(void)
697 {
698 	unsigned long linux_gateway_page_addr;
699 	/* FIXME: This is 'const' in order to trick the compiler
700 	   into not treating it as DP-relative data. */
701 	extern void * const linux_gateway_page;
702 
703 	linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
704 
705 	/*
706 	 * Setup Linux Gateway page.
707 	 *
708 	 * The Linux gateway page will reside in kernel space (on virtual
709 	 * page 0), so it doesn't need to be aliased into user space.
710 	 */
711 
712 	map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
713 		PAGE_SIZE, PAGE_GATEWAY);
714 }
715 
716 #ifdef CONFIG_HPUX
717 void
718 map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm)
719 {
720 	pgd_t *pg_dir;
721 	pmd_t *pmd;
722 	pte_t *pg_table;
723 	unsigned long start_pmd;
724 	unsigned long start_pte;
725 	unsigned long address;
726 	unsigned long hpux_gw_page_addr;
727 	/* FIXME: This is 'const' in order to trick the compiler
728 	   into not treating it as DP-relative data. */
729 	extern void * const hpux_gateway_page;
730 
731 	hpux_gw_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
732 
733 	/*
734 	 * Setup HP-UX Gateway page.
735 	 *
736 	 * The HP-UX gateway page resides in the user address space,
737 	 * so it needs to be aliased into each process.
738 	 */
739 
740 	pg_dir = pgd_offset(mm,hpux_gw_page_addr);
741 
742 #if PTRS_PER_PMD == 1
743 	start_pmd = 0;
744 #else
745 	start_pmd = ((hpux_gw_page_addr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
746 #endif
747 	start_pte = ((hpux_gw_page_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
748 
749 	address = __pa(&hpux_gateway_page);
750 #if PTRS_PER_PMD == 1
751 	pmd = (pmd_t *)__pa(pg_dir);
752 #else
753 	pmd = (pmd_t *) pgd_address(*pg_dir);
754 
755 	/*
756 	 * pmd is physical at this point
757 	 */
758 
759 	if (!pmd) {
760 		pmd = (pmd_t *) get_zeroed_page(GFP_KERNEL);
761 		pmd = (pmd_t *) __pa(pmd);
762 	}
763 
764 	__pgd_val_set(*pg_dir, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pmd);
765 #endif
766 	/* now change pmd to kernel virtual addresses */
767 
768 	pmd = (pmd_t *)__va(pmd) + start_pmd;
769 
770 	/*
771 	 * pg_table is physical at this point
772 	 */
773 
774 	pg_table = (pte_t *) pmd_address(*pmd);
775 	if (!pg_table)
776 		pg_table = (pte_t *) __pa(get_zeroed_page(GFP_KERNEL));
777 
778 	__pmd_val_set(*pmd, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pg_table);
779 
780 	/* now change pg_table to kernel virtual addresses */
781 
782 	pg_table = (pte_t *) __va(pg_table) + start_pte;
783 	set_pte(pg_table, __mk_pte(address, PAGE_GATEWAY));
784 }
785 EXPORT_SYMBOL(map_hpux_gateway_page);
786 #endif
787 
788 extern void flush_tlb_all_local(void);
789 
790 void __init paging_init(void)
791 {
792 	int i;
793 
794 	setup_bootmem();
795 	pagetable_init();
796 	gateway_init();
797 	flush_cache_all_local(); /* start with known state */
798 	flush_tlb_all_local();
799 
800 	for (i = 0; i < npmem_ranges; i++) {
801 		unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0 };
802 
803 		/* We have an IOMMU, so all memory can go into a single
804 		   ZONE_DMA zone. */
805 		zones_size[ZONE_DMA] = pmem_ranges[i].pages;
806 
807 #ifdef CONFIG_DISCONTIGMEM
808 		/* Need to initialize the pfnnid_map before we can initialize
809 		   the zone */
810 		{
811 		    int j;
812 		    for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
813 			 j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
814 			 j++) {
815 			pfnnid_map[j] = i;
816 		    }
817 		}
818 #endif
819 
820 		free_area_init_node(i, NODE_DATA(i), zones_size,
821 				pmem_ranges[i].start_pfn, NULL);
822 	}
823 }
824 
825 #ifdef CONFIG_PA20
826 
827 /*
828  * Currently, all PA20 chips have 18 bit protection id's, which is the
829  * limiting factor (space ids are 32 bits).
830  */
831 
832 #define NR_SPACE_IDS 262144
833 
834 #else
835 
836 /*
837  * Currently we have a one-to-one relationship between space id's and
838  * protection id's. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
839  * support 15 bit protection id's, so that is the limiting factor.
840  * PCXT' has 18 bit protection id's, but only 16 bit spaceids, so it's
841  * probably not worth the effort for a special case here.
842  */
843 
844 #define NR_SPACE_IDS 32768
845 
846 #endif  /* !CONFIG_PA20 */
847 
848 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
849 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
850 
851 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
852 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
853 static unsigned long space_id_index;
854 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
855 static unsigned long dirty_space_ids = 0;
856 
857 static DEFINE_SPINLOCK(sid_lock);
858 
859 unsigned long alloc_sid(void)
860 {
861 	unsigned long index;
862 
863 	spin_lock(&sid_lock);
864 
865 	if (free_space_ids == 0) {
866 		if (dirty_space_ids != 0) {
867 			spin_unlock(&sid_lock);
868 			flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
869 			spin_lock(&sid_lock);
870 		}
871 		if (free_space_ids == 0)
872 			BUG();
873 	}
874 
875 	free_space_ids--;
876 
877 	index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
878 	space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
879 	space_id_index = index;
880 
881 	spin_unlock(&sid_lock);
882 
883 	return index << SPACEID_SHIFT;
884 }
885 
886 void free_sid(unsigned long spaceid)
887 {
888 	unsigned long index = spaceid >> SPACEID_SHIFT;
889 	unsigned long *dirty_space_offset;
890 
891 	dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
892 	index &= (BITS_PER_LONG - 1);
893 
894 	spin_lock(&sid_lock);
895 
896 	if (*dirty_space_offset & (1L << index))
897 	    BUG(); /* attempt to free space id twice */
898 
899 	*dirty_space_offset |= (1L << index);
900 	dirty_space_ids++;
901 
902 	spin_unlock(&sid_lock);
903 }
904 
905 
906 #ifdef CONFIG_SMP
907 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
908 {
909 	int i;
910 
911 	/* NOTE: sid_lock must be held upon entry */
912 
913 	*ndirtyptr = dirty_space_ids;
914 	if (dirty_space_ids != 0) {
915 	    for (i = 0; i < SID_ARRAY_SIZE; i++) {
916 		dirty_array[i] = dirty_space_id[i];
917 		dirty_space_id[i] = 0;
918 	    }
919 	    dirty_space_ids = 0;
920 	}
921 
922 	return;
923 }
924 
925 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
926 {
927 	int i;
928 
929 	/* NOTE: sid_lock must be held upon entry */
930 
931 	if (ndirty != 0) {
932 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
933 			space_id[i] ^= dirty_array[i];
934 		}
935 
936 		free_space_ids += ndirty;
937 		space_id_index = 0;
938 	}
939 }
940 
941 #else /* CONFIG_SMP */
942 
943 static void recycle_sids(void)
944 {
945 	int i;
946 
947 	/* NOTE: sid_lock must be held upon entry */
948 
949 	if (dirty_space_ids != 0) {
950 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
951 			space_id[i] ^= dirty_space_id[i];
952 			dirty_space_id[i] = 0;
953 		}
954 
955 		free_space_ids += dirty_space_ids;
956 		dirty_space_ids = 0;
957 		space_id_index = 0;
958 	}
959 }
960 #endif
961 
962 /*
963  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
964  * purged, we can safely reuse the space ids that were released but
965  * not flushed from the tlb.
966  */
967 
968 #ifdef CONFIG_SMP
969 
970 static unsigned long recycle_ndirty;
971 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
972 static unsigned int recycle_inuse = 0;
973 
974 void flush_tlb_all(void)
975 {
976 	int do_recycle;
977 
978 	do_recycle = 0;
979 	spin_lock(&sid_lock);
980 	if (dirty_space_ids > RECYCLE_THRESHOLD) {
981 	    if (recycle_inuse) {
982 		BUG();  /* FIXME: Use a semaphore/wait queue here */
983 	    }
984 	    get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
985 	    recycle_inuse++;
986 	    do_recycle++;
987 	}
988 	spin_unlock(&sid_lock);
989 	on_each_cpu((void (*)(void *))flush_tlb_all_local, NULL, 1, 1);
990 	if (do_recycle) {
991 	    spin_lock(&sid_lock);
992 	    recycle_sids(recycle_ndirty,recycle_dirty_array);
993 	    recycle_inuse = 0;
994 	    spin_unlock(&sid_lock);
995 	}
996 }
997 #else
998 void flush_tlb_all(void)
999 {
1000 	spin_lock(&sid_lock);
1001 	flush_tlb_all_local();
1002 	recycle_sids();
1003 	spin_unlock(&sid_lock);
1004 }
1005 #endif
1006 
1007 #ifdef CONFIG_BLK_DEV_INITRD
1008 void free_initrd_mem(unsigned long start, unsigned long end)
1009 {
1010 #if 0
1011 	if (start < end)
1012 		printk(KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
1013 	for (; start < end; start += PAGE_SIZE) {
1014 		ClearPageReserved(virt_to_page(start));
1015 		set_page_count(virt_to_page(start), 1);
1016 		free_page(start);
1017 		num_physpages++;
1018 		totalram_pages++;
1019 	}
1020 #endif
1021 }
1022 #endif
1023