xref: /openbmc/linux/arch/parisc/mm/init.c (revision b05005772f34497eb2b7415a651fe785cbe70e16)
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] __read_mostly;
40 bootmem_data_t bmem_data[MAX_NUMNODES] __read_mostly;
41 unsigned char pfnnid_map[PFNNID_MAP_MAX] __read_mostly;
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] __read_mostly;
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] __read_mostly;
68 int npmem_ranges __read_mostly;
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 __read_mostly = 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 	/* IOMMU is always used to access "high mem" on those boxes
304 	 * that can support enough mem that a PCI device couldn't
305 	 * directly DMA to any physical addresses.
306 	 * ISA DMA support will need to revisit this.
307 	 */
308 	max_low_pfn = max_pfn;
309 
310 	if ((bootmap_pfn - bootmap_start_pfn) != bootmap_pages) {
311 		printk(KERN_WARNING "WARNING! bootmap sizing is messed up!\n");
312 		BUG();
313 	}
314 
315 	/* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
316 
317 #define PDC_CONSOLE_IO_IODC_SIZE 32768
318 
319 	reserve_bootmem_node(NODE_DATA(0), 0UL,
320 			(unsigned long)(PAGE0->mem_free + PDC_CONSOLE_IO_IODC_SIZE));
321 	reserve_bootmem_node(NODE_DATA(0),__pa((unsigned long)&_text),
322 			(unsigned long)(&_end - &_text));
323 	reserve_bootmem_node(NODE_DATA(0), (bootmap_start_pfn << PAGE_SHIFT),
324 			((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT));
325 
326 #ifndef CONFIG_DISCONTIGMEM
327 
328 	/* reserve the holes */
329 
330 	for (i = 0; i < npmem_holes; i++) {
331 		reserve_bootmem_node(NODE_DATA(0),
332 				(pmem_holes[i].start_pfn << PAGE_SHIFT),
333 				(pmem_holes[i].pages << PAGE_SHIFT));
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), initrd_reserve);
352 		}
353 	}
354 #endif
355 
356 	data_resource.start =  virt_to_phys(&data_start);
357 	data_resource.end = virt_to_phys(&_end)-1;
358 	code_resource.start = virt_to_phys(&_text);
359 	code_resource.end = virt_to_phys(&data_start)-1;
360 
361 	/* We don't know which region the kernel will be in, so try
362 	 * all of them.
363 	 */
364 	for (i = 0; i < sysram_resource_count; i++) {
365 		struct resource *res = &sysram_resources[i];
366 		request_resource(res, &code_resource);
367 		request_resource(res, &data_resource);
368 	}
369 	request_resource(&sysram_resources[0], &pdcdata_resource);
370 }
371 
372 void free_initmem(void)
373 {
374 	unsigned long addr;
375 
376 	printk(KERN_INFO "Freeing unused kernel memory: ");
377 
378 #ifdef CONFIG_DEBUG_KERNEL
379 	/* Attempt to catch anyone trying to execute code here
380 	 * by filling the page with BRK insns.
381 	 *
382 	 * If we disable interrupts for all CPUs, then IPI stops working.
383 	 * Kinda breaks the global cache flushing.
384 	 */
385 	local_irq_disable();
386 
387 	memset(&__init_begin, 0x00,
388 		(unsigned long)&__init_end - (unsigned long)&__init_begin);
389 
390 	flush_data_cache();
391 	asm volatile("sync" : : );
392 	flush_icache_range((unsigned long)&__init_begin, (unsigned long)&__init_end);
393 	asm volatile("sync" : : );
394 
395 	local_irq_enable();
396 #endif
397 
398 	addr = (unsigned long)(&__init_begin);
399 	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
400 		ClearPageReserved(virt_to_page(addr));
401 		set_page_count(virt_to_page(addr), 1);
402 		free_page(addr);
403 		num_physpages++;
404 		totalram_pages++;
405 	}
406 
407 	/* set up a new led state on systems shipped LED State panel */
408 	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
409 
410 	printk("%luk freed\n", (unsigned long)(&__init_end - &__init_begin) >> 10);
411 }
412 
413 
414 #ifdef CONFIG_DEBUG_RODATA
415 void mark_rodata_ro(void)
416 {
417 	extern char __start_rodata, __end_rodata;
418 	/* rodata memory was already mapped with KERNEL_RO access rights by
419            pagetable_init() and map_pages(). No need to do additional stuff here */
420 	printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
421 		(unsigned long)(&__end_rodata - &__start_rodata) >> 10);
422 }
423 #endif
424 
425 
426 /*
427  * Just an arbitrary offset to serve as a "hole" between mapping areas
428  * (between top of physical memory and a potential pcxl dma mapping
429  * area, and below the vmalloc mapping area).
430  *
431  * The current 32K value just means that there will be a 32K "hole"
432  * between mapping areas. That means that  any out-of-bounds memory
433  * accesses will hopefully be caught. The vmalloc() routines leaves
434  * a hole of 4kB between each vmalloced area for the same reason.
435  */
436 
437  /* Leave room for gateway page expansion */
438 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
439 #error KERNEL_MAP_START is in gateway reserved region
440 #endif
441 #define MAP_START (KERNEL_MAP_START)
442 
443 #define VM_MAP_OFFSET  (32*1024)
444 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
445 				     & ~(VM_MAP_OFFSET-1)))
446 
447 void *vmalloc_start __read_mostly;
448 EXPORT_SYMBOL(vmalloc_start);
449 
450 #ifdef CONFIG_PA11
451 unsigned long pcxl_dma_start __read_mostly;
452 #endif
453 
454 void __init mem_init(void)
455 {
456 	high_memory = __va((max_pfn << PAGE_SHIFT));
457 
458 #ifndef CONFIG_DISCONTIGMEM
459 	max_mapnr = page_to_pfn(virt_to_page(high_memory - 1)) + 1;
460 	totalram_pages += free_all_bootmem();
461 #else
462 	{
463 		int i;
464 
465 		for (i = 0; i < npmem_ranges; i++)
466 			totalram_pages += free_all_bootmem_node(NODE_DATA(i));
467 	}
468 #endif
469 
470 	printk(KERN_INFO "Memory: %luk available\n", num_physpages << (PAGE_SHIFT-10));
471 
472 #ifdef CONFIG_PA11
473 	if (hppa_dma_ops == &pcxl_dma_ops) {
474 		pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
475 		vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE);
476 	} else {
477 		pcxl_dma_start = 0;
478 		vmalloc_start = SET_MAP_OFFSET(MAP_START);
479 	}
480 #else
481 	vmalloc_start = SET_MAP_OFFSET(MAP_START);
482 #endif
483 
484 }
485 
486 unsigned long *empty_zero_page __read_mostly;
487 
488 void show_mem(void)
489 {
490 	int i,free = 0,total = 0,reserved = 0;
491 	int shared = 0, cached = 0;
492 
493 	printk(KERN_INFO "Mem-info:\n");
494 	show_free_areas();
495 	printk(KERN_INFO "Free swap:	 %6ldkB\n",
496 				nr_swap_pages<<(PAGE_SHIFT-10));
497 #ifndef CONFIG_DISCONTIGMEM
498 	i = max_mapnr;
499 	while (i-- > 0) {
500 		total++;
501 		if (PageReserved(mem_map+i))
502 			reserved++;
503 		else if (PageSwapCache(mem_map+i))
504 			cached++;
505 		else if (!page_count(&mem_map[i]))
506 			free++;
507 		else
508 			shared += page_count(&mem_map[i]) - 1;
509 	}
510 #else
511 	for (i = 0; i < npmem_ranges; i++) {
512 		int j;
513 
514 		for (j = node_start_pfn(i); j < node_end_pfn(i); j++) {
515 			struct page *p;
516 			unsigned long flags;
517 
518 			pgdat_resize_lock(NODE_DATA(i), &flags);
519 			p = nid_page_nr(i, j) - node_start_pfn(i);
520 
521 			total++;
522 			if (PageReserved(p))
523 				reserved++;
524 			else if (PageSwapCache(p))
525 				cached++;
526 			else if (!page_count(p))
527 				free++;
528 			else
529 				shared += page_count(p) - 1;
530 			pgdat_resize_unlock(NODE_DATA(i), &flags);
531         	}
532 	}
533 #endif
534 	printk(KERN_INFO "%d pages of RAM\n", total);
535 	printk(KERN_INFO "%d reserved pages\n", reserved);
536 	printk(KERN_INFO "%d pages shared\n", shared);
537 	printk(KERN_INFO "%d pages swap cached\n", cached);
538 
539 
540 #ifdef CONFIG_DISCONTIGMEM
541 	{
542 		struct zonelist *zl;
543 		int i, j, k;
544 
545 		for (i = 0; i < npmem_ranges; i++) {
546 			for (j = 0; j < MAX_NR_ZONES; j++) {
547 				zl = NODE_DATA(i)->node_zonelists + j;
548 
549 				printk("Zone list for zone %d on node %d: ", j, i);
550 				for (k = 0; zl->zones[k] != NULL; k++)
551 					printk("[%d/%s] ", zl->zones[k]->zone_pgdat->node_id, zl->zones[k]->name);
552 				printk("\n");
553 			}
554 		}
555 	}
556 #endif
557 }
558 
559 
560 static void __init map_pages(unsigned long start_vaddr, unsigned long start_paddr, unsigned long size, pgprot_t pgprot)
561 {
562 	pgd_t *pg_dir;
563 	pmd_t *pmd;
564 	pte_t *pg_table;
565 	unsigned long end_paddr;
566 	unsigned long start_pmd;
567 	unsigned long start_pte;
568 	unsigned long tmp1;
569 	unsigned long tmp2;
570 	unsigned long address;
571 	unsigned long ro_start;
572 	unsigned long ro_end;
573 	unsigned long fv_addr;
574 	unsigned long gw_addr;
575 	extern const unsigned long fault_vector_20;
576 	extern void * const linux_gateway_page;
577 
578 	ro_start = __pa((unsigned long)&_text);
579 	ro_end   = __pa((unsigned long)&data_start);
580 	fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
581 	gw_addr  = __pa((unsigned long)&linux_gateway_page) & PAGE_MASK;
582 
583 	end_paddr = start_paddr + size;
584 
585 	pg_dir = pgd_offset_k(start_vaddr);
586 
587 #if PTRS_PER_PMD == 1
588 	start_pmd = 0;
589 #else
590 	start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
591 #endif
592 	start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
593 
594 	address = start_paddr;
595 	while (address < end_paddr) {
596 #if PTRS_PER_PMD == 1
597 		pmd = (pmd_t *)__pa(pg_dir);
598 #else
599 		pmd = (pmd_t *)pgd_address(*pg_dir);
600 
601 		/*
602 		 * pmd is physical at this point
603 		 */
604 
605 		if (!pmd) {
606 			pmd = (pmd_t *) alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE << PMD_ORDER);
607 			pmd = (pmd_t *) __pa(pmd);
608 		}
609 
610 		pgd_populate(NULL, pg_dir, __va(pmd));
611 #endif
612 		pg_dir++;
613 
614 		/* now change pmd to kernel virtual addresses */
615 
616 		pmd = (pmd_t *)__va(pmd) + start_pmd;
617 		for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++,pmd++) {
618 
619 			/*
620 			 * pg_table is physical at this point
621 			 */
622 
623 			pg_table = (pte_t *)pmd_address(*pmd);
624 			if (!pg_table) {
625 				pg_table = (pte_t *)
626 					alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE);
627 				pg_table = (pte_t *) __pa(pg_table);
628 			}
629 
630 			pmd_populate_kernel(NULL, pmd, __va(pg_table));
631 
632 			/* now change pg_table to kernel virtual addresses */
633 
634 			pg_table = (pte_t *) __va(pg_table) + start_pte;
635 			for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++,pg_table++) {
636 				pte_t pte;
637 
638 				/*
639 				 * Map the fault vector writable so we can
640 				 * write the HPMC checksum.
641 				 */
642 				if (address >= ro_start && address < ro_end
643 							&& address != fv_addr
644 							&& address != gw_addr)
645 				    pte = __mk_pte(address, PAGE_KERNEL_RO);
646 				else
647 				    pte = __mk_pte(address, pgprot);
648 
649 				if (address >= end_paddr)
650 					pte_val(pte) = 0;
651 
652 				set_pte(pg_table, pte);
653 
654 				address += PAGE_SIZE;
655 			}
656 			start_pte = 0;
657 
658 			if (address >= end_paddr)
659 			    break;
660 		}
661 		start_pmd = 0;
662 	}
663 }
664 
665 /*
666  * pagetable_init() sets up the page tables
667  *
668  * Note that gateway_init() places the Linux gateway page at page 0.
669  * Since gateway pages cannot be dereferenced this has the desirable
670  * side effect of trapping those pesky NULL-reference errors in the
671  * kernel.
672  */
673 static void __init pagetable_init(void)
674 {
675 	int range;
676 
677 	/* Map each physical memory range to its kernel vaddr */
678 
679 	for (range = 0; range < npmem_ranges; range++) {
680 		unsigned long start_paddr;
681 		unsigned long end_paddr;
682 		unsigned long size;
683 
684 		start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
685 		end_paddr = start_paddr + (pmem_ranges[range].pages << PAGE_SHIFT);
686 		size = pmem_ranges[range].pages << PAGE_SHIFT;
687 
688 		map_pages((unsigned long)__va(start_paddr), start_paddr,
689 			size, PAGE_KERNEL);
690 	}
691 
692 #ifdef CONFIG_BLK_DEV_INITRD
693 	if (initrd_end && initrd_end > mem_limit) {
694 		printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
695 		map_pages(initrd_start, __pa(initrd_start),
696 			initrd_end - initrd_start, PAGE_KERNEL);
697 	}
698 #endif
699 
700 	empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
701 	memset(empty_zero_page, 0, PAGE_SIZE);
702 }
703 
704 static void __init gateway_init(void)
705 {
706 	unsigned long linux_gateway_page_addr;
707 	/* FIXME: This is 'const' in order to trick the compiler
708 	   into not treating it as DP-relative data. */
709 	extern void * const linux_gateway_page;
710 
711 	linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
712 
713 	/*
714 	 * Setup Linux Gateway page.
715 	 *
716 	 * The Linux gateway page will reside in kernel space (on virtual
717 	 * page 0), so it doesn't need to be aliased into user space.
718 	 */
719 
720 	map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
721 		PAGE_SIZE, PAGE_GATEWAY);
722 }
723 
724 #ifdef CONFIG_HPUX
725 void
726 map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm)
727 {
728 	pgd_t *pg_dir;
729 	pmd_t *pmd;
730 	pte_t *pg_table;
731 	unsigned long start_pmd;
732 	unsigned long start_pte;
733 	unsigned long address;
734 	unsigned long hpux_gw_page_addr;
735 	/* FIXME: This is 'const' in order to trick the compiler
736 	   into not treating it as DP-relative data. */
737 	extern void * const hpux_gateway_page;
738 
739 	hpux_gw_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
740 
741 	/*
742 	 * Setup HP-UX Gateway page.
743 	 *
744 	 * The HP-UX gateway page resides in the user address space,
745 	 * so it needs to be aliased into each process.
746 	 */
747 
748 	pg_dir = pgd_offset(mm,hpux_gw_page_addr);
749 
750 #if PTRS_PER_PMD == 1
751 	start_pmd = 0;
752 #else
753 	start_pmd = ((hpux_gw_page_addr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
754 #endif
755 	start_pte = ((hpux_gw_page_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
756 
757 	address = __pa(&hpux_gateway_page);
758 #if PTRS_PER_PMD == 1
759 	pmd = (pmd_t *)__pa(pg_dir);
760 #else
761 	pmd = (pmd_t *) pgd_address(*pg_dir);
762 
763 	/*
764 	 * pmd is physical at this point
765 	 */
766 
767 	if (!pmd) {
768 		pmd = (pmd_t *) get_zeroed_page(GFP_KERNEL);
769 		pmd = (pmd_t *) __pa(pmd);
770 	}
771 
772 	__pgd_val_set(*pg_dir, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pmd);
773 #endif
774 	/* now change pmd to kernel virtual addresses */
775 
776 	pmd = (pmd_t *)__va(pmd) + start_pmd;
777 
778 	/*
779 	 * pg_table is physical at this point
780 	 */
781 
782 	pg_table = (pte_t *) pmd_address(*pmd);
783 	if (!pg_table)
784 		pg_table = (pte_t *) __pa(get_zeroed_page(GFP_KERNEL));
785 
786 	__pmd_val_set(*pmd, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pg_table);
787 
788 	/* now change pg_table to kernel virtual addresses */
789 
790 	pg_table = (pte_t *) __va(pg_table) + start_pte;
791 	set_pte(pg_table, __mk_pte(address, PAGE_GATEWAY));
792 }
793 EXPORT_SYMBOL(map_hpux_gateway_page);
794 #endif
795 
796 void __init paging_init(void)
797 {
798 	int i;
799 
800 	setup_bootmem();
801 	pagetable_init();
802 	gateway_init();
803 	flush_cache_all_local(); /* start with known state */
804 	flush_tlb_all_local(NULL);
805 
806 	for (i = 0; i < npmem_ranges; i++) {
807 		unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0 };
808 
809 		/* We have an IOMMU, so all memory can go into a single
810 		   ZONE_DMA zone. */
811 		zones_size[ZONE_DMA] = pmem_ranges[i].pages;
812 
813 #ifdef CONFIG_DISCONTIGMEM
814 		/* Need to initialize the pfnnid_map before we can initialize
815 		   the zone */
816 		{
817 		    int j;
818 		    for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
819 			 j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
820 			 j++) {
821 			pfnnid_map[j] = i;
822 		    }
823 		}
824 #endif
825 
826 		free_area_init_node(i, NODE_DATA(i), zones_size,
827 				pmem_ranges[i].start_pfn, NULL);
828 	}
829 }
830 
831 #ifdef CONFIG_PA20
832 
833 /*
834  * Currently, all PA20 chips have 18 bit protection id's, which is the
835  * limiting factor (space ids are 32 bits).
836  */
837 
838 #define NR_SPACE_IDS 262144
839 
840 #else
841 
842 /*
843  * Currently we have a one-to-one relationship between space id's and
844  * protection id's. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
845  * support 15 bit protection id's, so that is the limiting factor.
846  * PCXT' has 18 bit protection id's, but only 16 bit spaceids, so it's
847  * probably not worth the effort for a special case here.
848  */
849 
850 #define NR_SPACE_IDS 32768
851 
852 #endif  /* !CONFIG_PA20 */
853 
854 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
855 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
856 
857 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
858 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
859 static unsigned long space_id_index;
860 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
861 static unsigned long dirty_space_ids = 0;
862 
863 static DEFINE_SPINLOCK(sid_lock);
864 
865 unsigned long alloc_sid(void)
866 {
867 	unsigned long index;
868 
869 	spin_lock(&sid_lock);
870 
871 	if (free_space_ids == 0) {
872 		if (dirty_space_ids != 0) {
873 			spin_unlock(&sid_lock);
874 			flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
875 			spin_lock(&sid_lock);
876 		}
877 		if (free_space_ids == 0)
878 			BUG();
879 	}
880 
881 	free_space_ids--;
882 
883 	index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
884 	space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
885 	space_id_index = index;
886 
887 	spin_unlock(&sid_lock);
888 
889 	return index << SPACEID_SHIFT;
890 }
891 
892 void free_sid(unsigned long spaceid)
893 {
894 	unsigned long index = spaceid >> SPACEID_SHIFT;
895 	unsigned long *dirty_space_offset;
896 
897 	dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
898 	index &= (BITS_PER_LONG - 1);
899 
900 	spin_lock(&sid_lock);
901 
902 	if (*dirty_space_offset & (1L << index))
903 	    BUG(); /* attempt to free space id twice */
904 
905 	*dirty_space_offset |= (1L << index);
906 	dirty_space_ids++;
907 
908 	spin_unlock(&sid_lock);
909 }
910 
911 
912 #ifdef CONFIG_SMP
913 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
914 {
915 	int i;
916 
917 	/* NOTE: sid_lock must be held upon entry */
918 
919 	*ndirtyptr = dirty_space_ids;
920 	if (dirty_space_ids != 0) {
921 	    for (i = 0; i < SID_ARRAY_SIZE; i++) {
922 		dirty_array[i] = dirty_space_id[i];
923 		dirty_space_id[i] = 0;
924 	    }
925 	    dirty_space_ids = 0;
926 	}
927 
928 	return;
929 }
930 
931 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
932 {
933 	int i;
934 
935 	/* NOTE: sid_lock must be held upon entry */
936 
937 	if (ndirty != 0) {
938 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
939 			space_id[i] ^= dirty_array[i];
940 		}
941 
942 		free_space_ids += ndirty;
943 		space_id_index = 0;
944 	}
945 }
946 
947 #else /* CONFIG_SMP */
948 
949 static void recycle_sids(void)
950 {
951 	int i;
952 
953 	/* NOTE: sid_lock must be held upon entry */
954 
955 	if (dirty_space_ids != 0) {
956 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
957 			space_id[i] ^= dirty_space_id[i];
958 			dirty_space_id[i] = 0;
959 		}
960 
961 		free_space_ids += dirty_space_ids;
962 		dirty_space_ids = 0;
963 		space_id_index = 0;
964 	}
965 }
966 #endif
967 
968 /*
969  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
970  * purged, we can safely reuse the space ids that were released but
971  * not flushed from the tlb.
972  */
973 
974 #ifdef CONFIG_SMP
975 
976 static unsigned long recycle_ndirty;
977 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
978 static unsigned int recycle_inuse = 0;
979 
980 void flush_tlb_all(void)
981 {
982 	int do_recycle;
983 
984 	do_recycle = 0;
985 	spin_lock(&sid_lock);
986 	if (dirty_space_ids > RECYCLE_THRESHOLD) {
987 	    if (recycle_inuse) {
988 		BUG();  /* FIXME: Use a semaphore/wait queue here */
989 	    }
990 	    get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
991 	    recycle_inuse++;
992 	    do_recycle++;
993 	}
994 	spin_unlock(&sid_lock);
995 	on_each_cpu(flush_tlb_all_local, NULL, 1, 1);
996 	if (do_recycle) {
997 	    spin_lock(&sid_lock);
998 	    recycle_sids(recycle_ndirty,recycle_dirty_array);
999 	    recycle_inuse = 0;
1000 	    spin_unlock(&sid_lock);
1001 	}
1002 }
1003 #else
1004 void flush_tlb_all(void)
1005 {
1006 	spin_lock(&sid_lock);
1007 	flush_tlb_all_local(NULL);
1008 	recycle_sids();
1009 	spin_unlock(&sid_lock);
1010 }
1011 #endif
1012 
1013 #ifdef CONFIG_BLK_DEV_INITRD
1014 void free_initrd_mem(unsigned long start, unsigned long end)
1015 {
1016 #if 0
1017 	if (start < end)
1018 		printk(KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
1019 	for (; start < end; start += PAGE_SIZE) {
1020 		ClearPageReserved(virt_to_page(start));
1021 		set_page_count(virt_to_page(start), 1);
1022 		free_page(start);
1023 		num_physpages++;
1024 		totalram_pages++;
1025 	}
1026 #endif
1027 }
1028 #endif
1029