xref: /openbmc/linux/arch/parisc/mm/init.c (revision 930beb5a)
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/gfp.h>
18 #include <linux/delay.h>
19 #include <linux/init.h>
20 #include <linux/pci.h>		/* for hppa_dma_ops and pcxl_dma_ops */
21 #include <linux/initrd.h>
22 #include <linux/swap.h>
23 #include <linux/unistd.h>
24 #include <linux/nodemask.h>	/* for node_online_map */
25 #include <linux/pagemap.h>	/* for release_pages and page_cache_release */
26 
27 #include <asm/pgalloc.h>
28 #include <asm/pgtable.h>
29 #include <asm/tlb.h>
30 #include <asm/pdc_chassis.h>
31 #include <asm/mmzone.h>
32 #include <asm/sections.h>
33 
34 extern int  data_start;
35 extern void parisc_kernel_start(void);	/* Kernel entry point in head.S */
36 
37 #if PT_NLEVELS == 3
38 /* NOTE: This layout exactly conforms to the hybrid L2/L3 page table layout
39  * with the first pmd adjacent to the pgd and below it. gcc doesn't actually
40  * guarantee that global objects will be laid out in memory in the same order
41  * as the order of declaration, so put these in different sections and use
42  * the linker script to order them. */
43 pmd_t pmd0[PTRS_PER_PMD] __attribute__ ((__section__ (".data..vm0.pmd"), aligned(PAGE_SIZE)));
44 #endif
45 
46 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__ ((__section__ (".data..vm0.pgd"), aligned(PAGE_SIZE)));
47 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __attribute__ ((__section__ (".data..vm0.pte"), aligned(PAGE_SIZE)));
48 
49 #ifdef CONFIG_DISCONTIGMEM
50 struct node_map_data node_data[MAX_NUMNODES] __read_mostly;
51 signed char pfnnid_map[PFNNID_MAP_MAX] __read_mostly;
52 #endif
53 
54 static struct resource data_resource = {
55 	.name	= "Kernel data",
56 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
57 };
58 
59 static struct resource code_resource = {
60 	.name	= "Kernel code",
61 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
62 };
63 
64 static struct resource pdcdata_resource = {
65 	.name	= "PDC data (Page Zero)",
66 	.start	= 0,
67 	.end	= 0x9ff,
68 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM,
69 };
70 
71 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __read_mostly;
72 
73 /* The following array is initialized from the firmware specific
74  * information retrieved in kernel/inventory.c.
75  */
76 
77 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __read_mostly;
78 int npmem_ranges __read_mostly;
79 
80 #ifdef CONFIG_64BIT
81 #define MAX_MEM         (~0UL)
82 #else /* !CONFIG_64BIT */
83 #define MAX_MEM         (3584U*1024U*1024U)
84 #endif /* !CONFIG_64BIT */
85 
86 static unsigned long mem_limit __read_mostly = MAX_MEM;
87 
88 static void __init mem_limit_func(void)
89 {
90 	char *cp, *end;
91 	unsigned long limit;
92 
93 	/* We need this before __setup() functions are called */
94 
95 	limit = MAX_MEM;
96 	for (cp = boot_command_line; *cp; ) {
97 		if (memcmp(cp, "mem=", 4) == 0) {
98 			cp += 4;
99 			limit = memparse(cp, &end);
100 			if (end != cp)
101 				break;
102 			cp = end;
103 		} else {
104 			while (*cp != ' ' && *cp)
105 				++cp;
106 			while (*cp == ' ')
107 				++cp;
108 		}
109 	}
110 
111 	if (limit < mem_limit)
112 		mem_limit = limit;
113 }
114 
115 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
116 
117 static void __init setup_bootmem(void)
118 {
119 	unsigned long bootmap_size;
120 	unsigned long mem_max;
121 	unsigned long bootmap_pages;
122 	unsigned long bootmap_start_pfn;
123 	unsigned long bootmap_pfn;
124 #ifndef CONFIG_DISCONTIGMEM
125 	physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
126 	int npmem_holes;
127 #endif
128 	int i, sysram_resource_count;
129 
130 	disable_sr_hashing(); /* Turn off space register hashing */
131 
132 	/*
133 	 * Sort the ranges. Since the number of ranges is typically
134 	 * small, and performance is not an issue here, just do
135 	 * a simple insertion sort.
136 	 */
137 
138 	for (i = 1; i < npmem_ranges; i++) {
139 		int j;
140 
141 		for (j = i; j > 0; j--) {
142 			unsigned long tmp;
143 
144 			if (pmem_ranges[j-1].start_pfn <
145 			    pmem_ranges[j].start_pfn) {
146 
147 				break;
148 			}
149 			tmp = pmem_ranges[j-1].start_pfn;
150 			pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn;
151 			pmem_ranges[j].start_pfn = tmp;
152 			tmp = pmem_ranges[j-1].pages;
153 			pmem_ranges[j-1].pages = pmem_ranges[j].pages;
154 			pmem_ranges[j].pages = tmp;
155 		}
156 	}
157 
158 #ifndef CONFIG_DISCONTIGMEM
159 	/*
160 	 * Throw out ranges that are too far apart (controlled by
161 	 * MAX_GAP).
162 	 */
163 
164 	for (i = 1; i < npmem_ranges; i++) {
165 		if (pmem_ranges[i].start_pfn -
166 			(pmem_ranges[i-1].start_pfn +
167 			 pmem_ranges[i-1].pages) > MAX_GAP) {
168 			npmem_ranges = i;
169 			printk("Large gap in memory detected (%ld pages). "
170 			       "Consider turning on CONFIG_DISCONTIGMEM\n",
171 			       pmem_ranges[i].start_pfn -
172 			       (pmem_ranges[i-1].start_pfn +
173 			        pmem_ranges[i-1].pages));
174 			break;
175 		}
176 	}
177 #endif
178 
179 	if (npmem_ranges > 1) {
180 
181 		/* Print the memory ranges */
182 
183 		printk(KERN_INFO "Memory Ranges:\n");
184 
185 		for (i = 0; i < npmem_ranges; i++) {
186 			unsigned long start;
187 			unsigned long size;
188 
189 			size = (pmem_ranges[i].pages << PAGE_SHIFT);
190 			start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
191 			printk(KERN_INFO "%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
192 				i,start, start + (size - 1), size >> 20);
193 		}
194 	}
195 
196 	sysram_resource_count = npmem_ranges;
197 	for (i = 0; i < sysram_resource_count; i++) {
198 		struct resource *res = &sysram_resources[i];
199 		res->name = "System RAM";
200 		res->start = pmem_ranges[i].start_pfn << PAGE_SHIFT;
201 		res->end = res->start + (pmem_ranges[i].pages << PAGE_SHIFT)-1;
202 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
203 		request_resource(&iomem_resource, res);
204 	}
205 
206 	/*
207 	 * For 32 bit kernels we limit the amount of memory we can
208 	 * support, in order to preserve enough kernel address space
209 	 * for other purposes. For 64 bit kernels we don't normally
210 	 * limit the memory, but this mechanism can be used to
211 	 * artificially limit the amount of memory (and it is written
212 	 * to work with multiple memory ranges).
213 	 */
214 
215 	mem_limit_func();       /* check for "mem=" argument */
216 
217 	mem_max = 0;
218 	for (i = 0; i < npmem_ranges; i++) {
219 		unsigned long rsize;
220 
221 		rsize = pmem_ranges[i].pages << PAGE_SHIFT;
222 		if ((mem_max + rsize) > mem_limit) {
223 			printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
224 			if (mem_max == mem_limit)
225 				npmem_ranges = i;
226 			else {
227 				pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
228 						       - (mem_max >> PAGE_SHIFT);
229 				npmem_ranges = i + 1;
230 				mem_max = mem_limit;
231 			}
232 			break;
233 		}
234 		mem_max += rsize;
235 	}
236 
237 	printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
238 
239 #ifndef CONFIG_DISCONTIGMEM
240 	/* Merge the ranges, keeping track of the holes */
241 
242 	{
243 		unsigned long end_pfn;
244 		unsigned long hole_pages;
245 
246 		npmem_holes = 0;
247 		end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
248 		for (i = 1; i < npmem_ranges; i++) {
249 
250 			hole_pages = pmem_ranges[i].start_pfn - end_pfn;
251 			if (hole_pages) {
252 				pmem_holes[npmem_holes].start_pfn = end_pfn;
253 				pmem_holes[npmem_holes++].pages = hole_pages;
254 				end_pfn += hole_pages;
255 			}
256 			end_pfn += pmem_ranges[i].pages;
257 		}
258 
259 		pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
260 		npmem_ranges = 1;
261 	}
262 #endif
263 
264 	bootmap_pages = 0;
265 	for (i = 0; i < npmem_ranges; i++)
266 		bootmap_pages += bootmem_bootmap_pages(pmem_ranges[i].pages);
267 
268 	bootmap_start_pfn = PAGE_ALIGN(__pa((unsigned long) &_end)) >> PAGE_SHIFT;
269 
270 #ifdef CONFIG_DISCONTIGMEM
271 	for (i = 0; i < MAX_PHYSMEM_RANGES; i++) {
272 		memset(NODE_DATA(i), 0, sizeof(pg_data_t));
273 		NODE_DATA(i)->bdata = &bootmem_node_data[i];
274 	}
275 	memset(pfnnid_map, 0xff, sizeof(pfnnid_map));
276 
277 	for (i = 0; i < npmem_ranges; i++) {
278 		node_set_state(i, N_NORMAL_MEMORY);
279 		node_set_online(i);
280 	}
281 #endif
282 
283 	/*
284 	 * Initialize and free the full range of memory in each range.
285 	 * Note that the only writing these routines do are to the bootmap,
286 	 * and we've made sure to locate the bootmap properly so that they
287 	 * won't be writing over anything important.
288 	 */
289 
290 	bootmap_pfn = bootmap_start_pfn;
291 	max_pfn = 0;
292 	for (i = 0; i < npmem_ranges; i++) {
293 		unsigned long start_pfn;
294 		unsigned long npages;
295 
296 		start_pfn = pmem_ranges[i].start_pfn;
297 		npages = pmem_ranges[i].pages;
298 
299 		bootmap_size = init_bootmem_node(NODE_DATA(i),
300 						bootmap_pfn,
301 						start_pfn,
302 						(start_pfn + npages) );
303 		free_bootmem_node(NODE_DATA(i),
304 				  (start_pfn << PAGE_SHIFT),
305 				  (npages << PAGE_SHIFT) );
306 		bootmap_pfn += (bootmap_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
307 		if ((start_pfn + npages) > max_pfn)
308 			max_pfn = start_pfn + npages;
309 	}
310 
311 	/* IOMMU is always used to access "high mem" on those boxes
312 	 * that can support enough mem that a PCI device couldn't
313 	 * directly DMA to any physical addresses.
314 	 * ISA DMA support will need to revisit this.
315 	 */
316 	max_low_pfn = max_pfn;
317 
318 	/* bootmap sizing messed up? */
319 	BUG_ON((bootmap_pfn - bootmap_start_pfn) != bootmap_pages);
320 
321 	/* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
322 
323 #define PDC_CONSOLE_IO_IODC_SIZE 32768
324 
325 	reserve_bootmem_node(NODE_DATA(0), 0UL,
326 			(unsigned long)(PAGE0->mem_free +
327 				PDC_CONSOLE_IO_IODC_SIZE), BOOTMEM_DEFAULT);
328 	reserve_bootmem_node(NODE_DATA(0), __pa(KERNEL_BINARY_TEXT_START),
329 			(unsigned long)(_end - KERNEL_BINARY_TEXT_START),
330 			BOOTMEM_DEFAULT);
331 	reserve_bootmem_node(NODE_DATA(0), (bootmap_start_pfn << PAGE_SHIFT),
332 			((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT),
333 			BOOTMEM_DEFAULT);
334 
335 #ifndef CONFIG_DISCONTIGMEM
336 
337 	/* reserve the holes */
338 
339 	for (i = 0; i < npmem_holes; i++) {
340 		reserve_bootmem_node(NODE_DATA(0),
341 				(pmem_holes[i].start_pfn << PAGE_SHIFT),
342 				(pmem_holes[i].pages << PAGE_SHIFT),
343 				BOOTMEM_DEFAULT);
344 	}
345 #endif
346 
347 #ifdef CONFIG_BLK_DEV_INITRD
348 	if (initrd_start) {
349 		printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
350 		if (__pa(initrd_start) < mem_max) {
351 			unsigned long initrd_reserve;
352 
353 			if (__pa(initrd_end) > mem_max) {
354 				initrd_reserve = mem_max - __pa(initrd_start);
355 			} else {
356 				initrd_reserve = initrd_end - initrd_start;
357 			}
358 			initrd_below_start_ok = 1;
359 			printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
360 
361 			reserve_bootmem_node(NODE_DATA(0), __pa(initrd_start),
362 					initrd_reserve, BOOTMEM_DEFAULT);
363 		}
364 	}
365 #endif
366 
367 	data_resource.start =  virt_to_phys(&data_start);
368 	data_resource.end = virt_to_phys(_end) - 1;
369 	code_resource.start = virt_to_phys(_text);
370 	code_resource.end = virt_to_phys(&data_start)-1;
371 
372 	/* We don't know which region the kernel will be in, so try
373 	 * all of them.
374 	 */
375 	for (i = 0; i < sysram_resource_count; i++) {
376 		struct resource *res = &sysram_resources[i];
377 		request_resource(res, &code_resource);
378 		request_resource(res, &data_resource);
379 	}
380 	request_resource(&sysram_resources[0], &pdcdata_resource);
381 }
382 
383 static int __init parisc_text_address(unsigned long vaddr)
384 {
385 	static unsigned long head_ptr __initdata;
386 
387 	if (!head_ptr)
388 		head_ptr = PAGE_MASK & (unsigned long)
389 			dereference_function_descriptor(&parisc_kernel_start);
390 
391 	return core_kernel_text(vaddr) || vaddr == head_ptr;
392 }
393 
394 static void __init map_pages(unsigned long start_vaddr,
395 			     unsigned long start_paddr, unsigned long size,
396 			     pgprot_t pgprot, int force)
397 {
398 	pgd_t *pg_dir;
399 	pmd_t *pmd;
400 	pte_t *pg_table;
401 	unsigned long end_paddr;
402 	unsigned long start_pmd;
403 	unsigned long start_pte;
404 	unsigned long tmp1;
405 	unsigned long tmp2;
406 	unsigned long address;
407 	unsigned long vaddr;
408 	unsigned long ro_start;
409 	unsigned long ro_end;
410 	unsigned long fv_addr;
411 	unsigned long gw_addr;
412 	extern const unsigned long fault_vector_20;
413 	extern void * const linux_gateway_page;
414 
415 	ro_start = __pa((unsigned long)_text);
416 	ro_end   = __pa((unsigned long)&data_start);
417 	fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
418 	gw_addr  = __pa((unsigned long)&linux_gateway_page) & PAGE_MASK;
419 
420 	end_paddr = start_paddr + size;
421 
422 	pg_dir = pgd_offset_k(start_vaddr);
423 
424 #if PTRS_PER_PMD == 1
425 	start_pmd = 0;
426 #else
427 	start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
428 #endif
429 	start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
430 
431 	address = start_paddr;
432 	vaddr = start_vaddr;
433 	while (address < end_paddr) {
434 #if PTRS_PER_PMD == 1
435 		pmd = (pmd_t *)__pa(pg_dir);
436 #else
437 		pmd = (pmd_t *)pgd_address(*pg_dir);
438 
439 		/*
440 		 * pmd is physical at this point
441 		 */
442 
443 		if (!pmd) {
444 			pmd = (pmd_t *) alloc_bootmem_low_pages_node(NODE_DATA(0), PAGE_SIZE << PMD_ORDER);
445 			pmd = (pmd_t *) __pa(pmd);
446 		}
447 
448 		pgd_populate(NULL, pg_dir, __va(pmd));
449 #endif
450 		pg_dir++;
451 
452 		/* now change pmd to kernel virtual addresses */
453 
454 		pmd = (pmd_t *)__va(pmd) + start_pmd;
455 		for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
456 
457 			/*
458 			 * pg_table is physical at this point
459 			 */
460 
461 			pg_table = (pte_t *)pmd_address(*pmd);
462 			if (!pg_table) {
463 				pg_table = (pte_t *)
464 					alloc_bootmem_low_pages_node(NODE_DATA(0), PAGE_SIZE);
465 				pg_table = (pte_t *) __pa(pg_table);
466 			}
467 
468 			pmd_populate_kernel(NULL, pmd, __va(pg_table));
469 
470 			/* now change pg_table to kernel virtual addresses */
471 
472 			pg_table = (pte_t *) __va(pg_table) + start_pte;
473 			for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
474 				pte_t pte;
475 
476 				/*
477 				 * Map the fault vector writable so we can
478 				 * write the HPMC checksum.
479 				 */
480 				if (force)
481 					pte =  __mk_pte(address, pgprot);
482 				else if (parisc_text_address(vaddr) &&
483 					 address != fv_addr)
484 					pte = __mk_pte(address, PAGE_KERNEL_EXEC);
485 				else
486 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
487 				if (address >= ro_start && address < ro_end
488 							&& address != fv_addr
489 							&& address != gw_addr)
490 					pte = __mk_pte(address, PAGE_KERNEL_RO);
491 				else
492 #endif
493 					pte = __mk_pte(address, pgprot);
494 
495 				if (address >= end_paddr) {
496 					if (force)
497 						break;
498 					else
499 						pte_val(pte) = 0;
500 				}
501 
502 				set_pte(pg_table, pte);
503 
504 				address += PAGE_SIZE;
505 				vaddr += PAGE_SIZE;
506 			}
507 			start_pte = 0;
508 
509 			if (address >= end_paddr)
510 			    break;
511 		}
512 		start_pmd = 0;
513 	}
514 }
515 
516 void free_initmem(void)
517 {
518 	unsigned long init_begin = (unsigned long)__init_begin;
519 	unsigned long init_end = (unsigned long)__init_end;
520 
521 	/* The init text pages are marked R-X.  We have to
522 	 * flush the icache and mark them RW-
523 	 *
524 	 * This is tricky, because map_pages is in the init section.
525 	 * Do a dummy remap of the data section first (the data
526 	 * section is already PAGE_KERNEL) to pull in the TLB entries
527 	 * for map_kernel */
528 	map_pages(init_begin, __pa(init_begin), init_end - init_begin,
529 		  PAGE_KERNEL_RWX, 1);
530 	/* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
531 	 * map_pages */
532 	map_pages(init_begin, __pa(init_begin), init_end - init_begin,
533 		  PAGE_KERNEL, 1);
534 
535 	/* force the kernel to see the new TLB entries */
536 	__flush_tlb_range(0, init_begin, init_end);
537 	/* Attempt to catch anyone trying to execute code here
538 	 * by filling the page with BRK insns.
539 	 */
540 	memset((void *)init_begin, 0x00, init_end - init_begin);
541 	/* finally dump all the instructions which were cached, since the
542 	 * pages are no-longer executable */
543 	flush_icache_range(init_begin, init_end);
544 
545 	free_initmem_default(-1);
546 
547 	/* set up a new led state on systems shipped LED State panel */
548 	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
549 }
550 
551 
552 #ifdef CONFIG_DEBUG_RODATA
553 void mark_rodata_ro(void)
554 {
555 	/* rodata memory was already mapped with KERNEL_RO access rights by
556            pagetable_init() and map_pages(). No need to do additional stuff here */
557 	printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
558 		(unsigned long)(__end_rodata - __start_rodata) >> 10);
559 }
560 #endif
561 
562 
563 /*
564  * Just an arbitrary offset to serve as a "hole" between mapping areas
565  * (between top of physical memory and a potential pcxl dma mapping
566  * area, and below the vmalloc mapping area).
567  *
568  * The current 32K value just means that there will be a 32K "hole"
569  * between mapping areas. That means that  any out-of-bounds memory
570  * accesses will hopefully be caught. The vmalloc() routines leaves
571  * a hole of 4kB between each vmalloced area for the same reason.
572  */
573 
574  /* Leave room for gateway page expansion */
575 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
576 #error KERNEL_MAP_START is in gateway reserved region
577 #endif
578 #define MAP_START (KERNEL_MAP_START)
579 
580 #define VM_MAP_OFFSET  (32*1024)
581 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
582 				     & ~(VM_MAP_OFFSET-1)))
583 
584 void *parisc_vmalloc_start __read_mostly;
585 EXPORT_SYMBOL(parisc_vmalloc_start);
586 
587 #ifdef CONFIG_PA11
588 unsigned long pcxl_dma_start __read_mostly;
589 #endif
590 
591 void __init mem_init(void)
592 {
593 	/* Do sanity checks on page table constants */
594 	BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
595 	BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
596 	BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
597 	BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
598 			> BITS_PER_LONG);
599 
600 	high_memory = __va((max_pfn << PAGE_SHIFT));
601 	set_max_mapnr(page_to_pfn(virt_to_page(high_memory - 1)) + 1);
602 	free_all_bootmem();
603 
604 #ifdef CONFIG_PA11
605 	if (hppa_dma_ops == &pcxl_dma_ops) {
606 		pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
607 		parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
608 						+ PCXL_DMA_MAP_SIZE);
609 	} else {
610 		pcxl_dma_start = 0;
611 		parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
612 	}
613 #else
614 	parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
615 #endif
616 
617 	mem_init_print_info(NULL);
618 #ifdef CONFIG_DEBUG_KERNEL /* double-sanity-check paranoia */
619 	printk("virtual kernel memory layout:\n"
620 	       "    vmalloc : 0x%p - 0x%p   (%4ld MB)\n"
621 	       "    memory  : 0x%p - 0x%p   (%4ld MB)\n"
622 	       "      .init : 0x%p - 0x%p   (%4ld kB)\n"
623 	       "      .data : 0x%p - 0x%p   (%4ld kB)\n"
624 	       "      .text : 0x%p - 0x%p   (%4ld kB)\n",
625 
626 	       (void*)VMALLOC_START, (void*)VMALLOC_END,
627 	       (VMALLOC_END - VMALLOC_START) >> 20,
628 
629 	       __va(0), high_memory,
630 	       ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
631 
632 	       __init_begin, __init_end,
633 	       ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
634 
635 	       _etext, _edata,
636 	       ((unsigned long)_edata - (unsigned long)_etext) >> 10,
637 
638 	       _text, _etext,
639 	       ((unsigned long)_etext - (unsigned long)_text) >> 10);
640 #endif
641 }
642 
643 unsigned long *empty_zero_page __read_mostly;
644 EXPORT_SYMBOL(empty_zero_page);
645 
646 void show_mem(unsigned int filter)
647 {
648 	int i,free = 0,total = 0,reserved = 0;
649 	int shared = 0, cached = 0;
650 
651 	printk(KERN_INFO "Mem-info:\n");
652 	show_free_areas(filter);
653 	if (filter & SHOW_MEM_FILTER_PAGE_COUNT)
654 		return;
655 #ifndef CONFIG_DISCONTIGMEM
656 	i = max_mapnr;
657 	while (i-- > 0) {
658 		total++;
659 		if (PageReserved(mem_map+i))
660 			reserved++;
661 		else if (PageSwapCache(mem_map+i))
662 			cached++;
663 		else if (!page_count(&mem_map[i]))
664 			free++;
665 		else
666 			shared += page_count(&mem_map[i]) - 1;
667 	}
668 #else
669 	for (i = 0; i < npmem_ranges; i++) {
670 		int j;
671 
672 		for (j = node_start_pfn(i); j < node_end_pfn(i); j++) {
673 			struct page *p;
674 			unsigned long flags;
675 
676 			pgdat_resize_lock(NODE_DATA(i), &flags);
677 			p = nid_page_nr(i, j) - node_start_pfn(i);
678 
679 			total++;
680 			if (PageReserved(p))
681 				reserved++;
682 			else if (PageSwapCache(p))
683 				cached++;
684 			else if (!page_count(p))
685 				free++;
686 			else
687 				shared += page_count(p) - 1;
688 			pgdat_resize_unlock(NODE_DATA(i), &flags);
689         	}
690 	}
691 #endif
692 	printk(KERN_INFO "%d pages of RAM\n", total);
693 	printk(KERN_INFO "%d reserved pages\n", reserved);
694 	printk(KERN_INFO "%d pages shared\n", shared);
695 	printk(KERN_INFO "%d pages swap cached\n", cached);
696 
697 
698 #ifdef CONFIG_DISCONTIGMEM
699 	{
700 		struct zonelist *zl;
701 		int i, j;
702 
703 		for (i = 0; i < npmem_ranges; i++) {
704 			zl = node_zonelist(i, 0);
705 			for (j = 0; j < MAX_NR_ZONES; j++) {
706 				struct zoneref *z;
707 				struct zone *zone;
708 
709 				printk("Zone list for zone %d on node %d: ", j, i);
710 				for_each_zone_zonelist(zone, z, zl, j)
711 					printk("[%d/%s] ", zone_to_nid(zone),
712 								zone->name);
713 				printk("\n");
714 			}
715 		}
716 	}
717 #endif
718 }
719 
720 /*
721  * pagetable_init() sets up the page tables
722  *
723  * Note that gateway_init() places the Linux gateway page at page 0.
724  * Since gateway pages cannot be dereferenced this has the desirable
725  * side effect of trapping those pesky NULL-reference errors in the
726  * kernel.
727  */
728 static void __init pagetable_init(void)
729 {
730 	int range;
731 
732 	/* Map each physical memory range to its kernel vaddr */
733 
734 	for (range = 0; range < npmem_ranges; range++) {
735 		unsigned long start_paddr;
736 		unsigned long end_paddr;
737 		unsigned long size;
738 
739 		start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
740 		end_paddr = start_paddr + (pmem_ranges[range].pages << PAGE_SHIFT);
741 		size = pmem_ranges[range].pages << PAGE_SHIFT;
742 
743 		map_pages((unsigned long)__va(start_paddr), start_paddr,
744 			  size, PAGE_KERNEL, 0);
745 	}
746 
747 #ifdef CONFIG_BLK_DEV_INITRD
748 	if (initrd_end && initrd_end > mem_limit) {
749 		printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
750 		map_pages(initrd_start, __pa(initrd_start),
751 			  initrd_end - initrd_start, PAGE_KERNEL, 0);
752 	}
753 #endif
754 
755 	empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
756 	memset(empty_zero_page, 0, PAGE_SIZE);
757 }
758 
759 static void __init gateway_init(void)
760 {
761 	unsigned long linux_gateway_page_addr;
762 	/* FIXME: This is 'const' in order to trick the compiler
763 	   into not treating it as DP-relative data. */
764 	extern void * const linux_gateway_page;
765 
766 	linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
767 
768 	/*
769 	 * Setup Linux Gateway page.
770 	 *
771 	 * The Linux gateway page will reside in kernel space (on virtual
772 	 * page 0), so it doesn't need to be aliased into user space.
773 	 */
774 
775 	map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
776 		  PAGE_SIZE, PAGE_GATEWAY, 1);
777 }
778 
779 #ifdef CONFIG_HPUX
780 void
781 map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm)
782 {
783 	pgd_t *pg_dir;
784 	pmd_t *pmd;
785 	pte_t *pg_table;
786 	unsigned long start_pmd;
787 	unsigned long start_pte;
788 	unsigned long address;
789 	unsigned long hpux_gw_page_addr;
790 	/* FIXME: This is 'const' in order to trick the compiler
791 	   into not treating it as DP-relative data. */
792 	extern void * const hpux_gateway_page;
793 
794 	hpux_gw_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
795 
796 	/*
797 	 * Setup HP-UX Gateway page.
798 	 *
799 	 * The HP-UX gateway page resides in the user address space,
800 	 * so it needs to be aliased into each process.
801 	 */
802 
803 	pg_dir = pgd_offset(mm,hpux_gw_page_addr);
804 
805 #if PTRS_PER_PMD == 1
806 	start_pmd = 0;
807 #else
808 	start_pmd = ((hpux_gw_page_addr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
809 #endif
810 	start_pte = ((hpux_gw_page_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
811 
812 	address = __pa(&hpux_gateway_page);
813 #if PTRS_PER_PMD == 1
814 	pmd = (pmd_t *)__pa(pg_dir);
815 #else
816 	pmd = (pmd_t *) pgd_address(*pg_dir);
817 
818 	/*
819 	 * pmd is physical at this point
820 	 */
821 
822 	if (!pmd) {
823 		pmd = (pmd_t *) get_zeroed_page(GFP_KERNEL);
824 		pmd = (pmd_t *) __pa(pmd);
825 	}
826 
827 	__pgd_val_set(*pg_dir, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pmd);
828 #endif
829 	/* now change pmd to kernel virtual addresses */
830 
831 	pmd = (pmd_t *)__va(pmd) + start_pmd;
832 
833 	/*
834 	 * pg_table is physical at this point
835 	 */
836 
837 	pg_table = (pte_t *) pmd_address(*pmd);
838 	if (!pg_table)
839 		pg_table = (pte_t *) __pa(get_zeroed_page(GFP_KERNEL));
840 
841 	__pmd_val_set(*pmd, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pg_table);
842 
843 	/* now change pg_table to kernel virtual addresses */
844 
845 	pg_table = (pte_t *) __va(pg_table) + start_pte;
846 	set_pte(pg_table, __mk_pte(address, PAGE_GATEWAY));
847 }
848 EXPORT_SYMBOL(map_hpux_gateway_page);
849 #endif
850 
851 void __init paging_init(void)
852 {
853 	int i;
854 
855 	setup_bootmem();
856 	pagetable_init();
857 	gateway_init();
858 	flush_cache_all_local(); /* start with known state */
859 	flush_tlb_all_local(NULL);
860 
861 	for (i = 0; i < npmem_ranges; i++) {
862 		unsigned long zones_size[MAX_NR_ZONES] = { 0, };
863 
864 		zones_size[ZONE_NORMAL] = pmem_ranges[i].pages;
865 
866 #ifdef CONFIG_DISCONTIGMEM
867 		/* Need to initialize the pfnnid_map before we can initialize
868 		   the zone */
869 		{
870 		    int j;
871 		    for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
872 			 j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
873 			 j++) {
874 			pfnnid_map[j] = i;
875 		    }
876 		}
877 #endif
878 
879 		free_area_init_node(i, zones_size,
880 				pmem_ranges[i].start_pfn, NULL);
881 	}
882 }
883 
884 #ifdef CONFIG_PA20
885 
886 /*
887  * Currently, all PA20 chips have 18 bit protection IDs, which is the
888  * limiting factor (space ids are 32 bits).
889  */
890 
891 #define NR_SPACE_IDS 262144
892 
893 #else
894 
895 /*
896  * Currently we have a one-to-one relationship between space IDs and
897  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
898  * support 15 bit protection IDs, so that is the limiting factor.
899  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
900  * probably not worth the effort for a special case here.
901  */
902 
903 #define NR_SPACE_IDS 32768
904 
905 #endif  /* !CONFIG_PA20 */
906 
907 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
908 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
909 
910 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
911 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
912 static unsigned long space_id_index;
913 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
914 static unsigned long dirty_space_ids = 0;
915 
916 static DEFINE_SPINLOCK(sid_lock);
917 
918 unsigned long alloc_sid(void)
919 {
920 	unsigned long index;
921 
922 	spin_lock(&sid_lock);
923 
924 	if (free_space_ids == 0) {
925 		if (dirty_space_ids != 0) {
926 			spin_unlock(&sid_lock);
927 			flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
928 			spin_lock(&sid_lock);
929 		}
930 		BUG_ON(free_space_ids == 0);
931 	}
932 
933 	free_space_ids--;
934 
935 	index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
936 	space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
937 	space_id_index = index;
938 
939 	spin_unlock(&sid_lock);
940 
941 	return index << SPACEID_SHIFT;
942 }
943 
944 void free_sid(unsigned long spaceid)
945 {
946 	unsigned long index = spaceid >> SPACEID_SHIFT;
947 	unsigned long *dirty_space_offset;
948 
949 	dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
950 	index &= (BITS_PER_LONG - 1);
951 
952 	spin_lock(&sid_lock);
953 
954 	BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
955 
956 	*dirty_space_offset |= (1L << index);
957 	dirty_space_ids++;
958 
959 	spin_unlock(&sid_lock);
960 }
961 
962 
963 #ifdef CONFIG_SMP
964 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
965 {
966 	int i;
967 
968 	/* NOTE: sid_lock must be held upon entry */
969 
970 	*ndirtyptr = dirty_space_ids;
971 	if (dirty_space_ids != 0) {
972 	    for (i = 0; i < SID_ARRAY_SIZE; i++) {
973 		dirty_array[i] = dirty_space_id[i];
974 		dirty_space_id[i] = 0;
975 	    }
976 	    dirty_space_ids = 0;
977 	}
978 
979 	return;
980 }
981 
982 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
983 {
984 	int i;
985 
986 	/* NOTE: sid_lock must be held upon entry */
987 
988 	if (ndirty != 0) {
989 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
990 			space_id[i] ^= dirty_array[i];
991 		}
992 
993 		free_space_ids += ndirty;
994 		space_id_index = 0;
995 	}
996 }
997 
998 #else /* CONFIG_SMP */
999 
1000 static void recycle_sids(void)
1001 {
1002 	int i;
1003 
1004 	/* NOTE: sid_lock must be held upon entry */
1005 
1006 	if (dirty_space_ids != 0) {
1007 		for (i = 0; i < SID_ARRAY_SIZE; i++) {
1008 			space_id[i] ^= dirty_space_id[i];
1009 			dirty_space_id[i] = 0;
1010 		}
1011 
1012 		free_space_ids += dirty_space_ids;
1013 		dirty_space_ids = 0;
1014 		space_id_index = 0;
1015 	}
1016 }
1017 #endif
1018 
1019 /*
1020  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
1021  * purged, we can safely reuse the space ids that were released but
1022  * not flushed from the tlb.
1023  */
1024 
1025 #ifdef CONFIG_SMP
1026 
1027 static unsigned long recycle_ndirty;
1028 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
1029 static unsigned int recycle_inuse;
1030 
1031 void flush_tlb_all(void)
1032 {
1033 	int do_recycle;
1034 
1035 	__inc_irq_stat(irq_tlb_count);
1036 	do_recycle = 0;
1037 	spin_lock(&sid_lock);
1038 	if (dirty_space_ids > RECYCLE_THRESHOLD) {
1039 	    BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
1040 	    get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
1041 	    recycle_inuse++;
1042 	    do_recycle++;
1043 	}
1044 	spin_unlock(&sid_lock);
1045 	on_each_cpu(flush_tlb_all_local, NULL, 1);
1046 	if (do_recycle) {
1047 	    spin_lock(&sid_lock);
1048 	    recycle_sids(recycle_ndirty,recycle_dirty_array);
1049 	    recycle_inuse = 0;
1050 	    spin_unlock(&sid_lock);
1051 	}
1052 }
1053 #else
1054 void flush_tlb_all(void)
1055 {
1056 	__inc_irq_stat(irq_tlb_count);
1057 	spin_lock(&sid_lock);
1058 	flush_tlb_all_local(NULL);
1059 	recycle_sids();
1060 	spin_unlock(&sid_lock);
1061 }
1062 #endif
1063 
1064 #ifdef CONFIG_BLK_DEV_INITRD
1065 void free_initrd_mem(unsigned long start, unsigned long end)
1066 {
1067 	free_reserved_area((void *)start, (void *)end, -1, "initrd");
1068 }
1069 #endif
1070