Pull bugzilla-5452 into release branch
[pandora-kernel.git] / arch / parisc / mm / init.c
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 Helge Deller (deller@gmx.de)
10  *
11  */
12
13 #include <linux/config.h>
14
15 #include <linux/module.h>
16 #include <linux/mm.h>
17 #include <linux/bootmem.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/tlb.h>
29 #include <asm/pdc_chassis.h>
30 #include <asm/mmzone.h>
31
32 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
33
34 extern char _text;      /* start of kernel code, defined by linker */
35 extern int  data_start;
36 extern char _end;       /* end of BSS, defined by linker */
37 extern char __init_begin, __init_end;
38
39 #ifdef CONFIG_DISCONTIGMEM
40 struct node_map_data node_data[MAX_NUMNODES] __read_mostly;
41 bootmem_data_t bmem_data[MAX_NUMNODES] __read_mostly;
42 unsigned char pfnnid_map[PFNNID_MAP_MAX] __read_mostly;
43 #endif
44
45 static struct resource data_resource = {
46         .name   = "Kernel data",
47         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
48 };
49
50 static struct resource code_resource = {
51         .name   = "Kernel code",
52         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
53 };
54
55 static struct resource pdcdata_resource = {
56         .name   = "PDC data (Page Zero)",
57         .start  = 0,
58         .end    = 0x9ff,
59         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
60 };
61
62 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __read_mostly;
63
64 /* The following array is initialized from the firmware specific
65  * information retrieved in kernel/inventory.c.
66  */
67
68 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __read_mostly;
69 int npmem_ranges __read_mostly;
70
71 #ifdef __LP64__
72 #define MAX_MEM         (~0UL)
73 #else /* !__LP64__ */
74 #define MAX_MEM         (3584U*1024U*1024U)
75 #endif /* !__LP64__ */
76
77 static unsigned long mem_limit __read_mostly = MAX_MEM;
78
79 static void __init mem_limit_func(void)
80 {
81         char *cp, *end;
82         unsigned long limit;
83         extern char saved_command_line[];
84
85         /* We need this before __setup() functions are called */
86
87         limit = MAX_MEM;
88         for (cp = saved_command_line; *cp; ) {
89                 if (memcmp(cp, "mem=", 4) == 0) {
90                         cp += 4;
91                         limit = memparse(cp, &end);
92                         if (end != cp)
93                                 break;
94                         cp = end;
95                 } else {
96                         while (*cp != ' ' && *cp)
97                                 ++cp;
98                         while (*cp == ' ')
99                                 ++cp;
100                 }
101         }
102
103         if (limit < mem_limit)
104                 mem_limit = limit;
105 }
106
107 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
108
109 static void __init setup_bootmem(void)
110 {
111         unsigned long bootmap_size;
112         unsigned long mem_max;
113         unsigned long bootmap_pages;
114         unsigned long bootmap_start_pfn;
115         unsigned long bootmap_pfn;
116 #ifndef CONFIG_DISCONTIGMEM
117         physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
118         int npmem_holes;
119 #endif
120         int i, sysram_resource_count;
121
122         disable_sr_hashing(); /* Turn off space register hashing */
123
124         /*
125          * Sort the ranges. Since the number of ranges is typically
126          * small, and performance is not an issue here, just do
127          * a simple insertion sort.
128          */
129
130         for (i = 1; i < npmem_ranges; i++) {
131                 int j;
132
133                 for (j = i; j > 0; j--) {
134                         unsigned long tmp;
135
136                         if (pmem_ranges[j-1].start_pfn <
137                             pmem_ranges[j].start_pfn) {
138
139                                 break;
140                         }
141                         tmp = pmem_ranges[j-1].start_pfn;
142                         pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn;
143                         pmem_ranges[j].start_pfn = tmp;
144                         tmp = pmem_ranges[j-1].pages;
145                         pmem_ranges[j-1].pages = pmem_ranges[j].pages;
146                         pmem_ranges[j].pages = tmp;
147                 }
148         }
149
150 #ifndef CONFIG_DISCONTIGMEM
151         /*
152          * Throw out ranges that are too far apart (controlled by
153          * MAX_GAP).
154          */
155
156         for (i = 1; i < npmem_ranges; i++) {
157                 if (pmem_ranges[i].start_pfn -
158                         (pmem_ranges[i-1].start_pfn +
159                          pmem_ranges[i-1].pages) > MAX_GAP) {
160                         npmem_ranges = i;
161                         printk("Large gap in memory detected (%ld pages). "
162                                "Consider turning on CONFIG_DISCONTIGMEM\n",
163                                pmem_ranges[i].start_pfn -
164                                (pmem_ranges[i-1].start_pfn +
165                                 pmem_ranges[i-1].pages));
166                         break;
167                 }
168         }
169 #endif
170
171         if (npmem_ranges > 1) {
172
173                 /* Print the memory ranges */
174
175                 printk(KERN_INFO "Memory Ranges:\n");
176
177                 for (i = 0; i < npmem_ranges; i++) {
178                         unsigned long start;
179                         unsigned long size;
180
181                         size = (pmem_ranges[i].pages << PAGE_SHIFT);
182                         start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
183                         printk(KERN_INFO "%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
184                                 i,start, start + (size - 1), size >> 20);
185                 }
186         }
187
188         sysram_resource_count = npmem_ranges;
189         for (i = 0; i < sysram_resource_count; i++) {
190                 struct resource *res = &sysram_resources[i];
191                 res->name = "System RAM";
192                 res->start = pmem_ranges[i].start_pfn << PAGE_SHIFT;
193                 res->end = res->start + (pmem_ranges[i].pages << PAGE_SHIFT)-1;
194                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
195                 request_resource(&iomem_resource, res);
196         }
197
198         /*
199          * For 32 bit kernels we limit the amount of memory we can
200          * support, in order to preserve enough kernel address space
201          * for other purposes. For 64 bit kernels we don't normally
202          * limit the memory, but this mechanism can be used to
203          * artificially limit the amount of memory (and it is written
204          * to work with multiple memory ranges).
205          */
206
207         mem_limit_func();       /* check for "mem=" argument */
208
209         mem_max = 0;
210         num_physpages = 0;
211         for (i = 0; i < npmem_ranges; i++) {
212                 unsigned long rsize;
213
214                 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
215                 if ((mem_max + rsize) > mem_limit) {
216                         printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
217                         if (mem_max == mem_limit)
218                                 npmem_ranges = i;
219                         else {
220                                 pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
221                                                        - (mem_max >> PAGE_SHIFT);
222                                 npmem_ranges = i + 1;
223                                 mem_max = mem_limit;
224                         }
225                 num_physpages += pmem_ranges[i].pages;
226                         break;
227                 }
228             num_physpages += pmem_ranges[i].pages;
229                 mem_max += rsize;
230         }
231
232         printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
233
234 #ifndef CONFIG_DISCONTIGMEM
235         /* Merge the ranges, keeping track of the holes */
236
237         {
238                 unsigned long end_pfn;
239                 unsigned long hole_pages;
240
241                 npmem_holes = 0;
242                 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
243                 for (i = 1; i < npmem_ranges; i++) {
244
245                         hole_pages = pmem_ranges[i].start_pfn - end_pfn;
246                         if (hole_pages) {
247                                 pmem_holes[npmem_holes].start_pfn = end_pfn;
248                                 pmem_holes[npmem_holes++].pages = hole_pages;
249                                 end_pfn += hole_pages;
250                         }
251                         end_pfn += pmem_ranges[i].pages;
252                 }
253
254                 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
255                 npmem_ranges = 1;
256         }
257 #endif
258
259         bootmap_pages = 0;
260         for (i = 0; i < npmem_ranges; i++)
261                 bootmap_pages += bootmem_bootmap_pages(pmem_ranges[i].pages);
262
263         bootmap_start_pfn = PAGE_ALIGN(__pa((unsigned long) &_end)) >> PAGE_SHIFT;
264
265 #ifdef CONFIG_DISCONTIGMEM
266         for (i = 0; i < MAX_PHYSMEM_RANGES; i++) {
267                 memset(NODE_DATA(i), 0, sizeof(pg_data_t));
268                 NODE_DATA(i)->bdata = &bmem_data[i];
269         }
270         memset(pfnnid_map, 0xff, sizeof(pfnnid_map));
271
272         for (i = 0; i < npmem_ranges; i++)
273                 node_set_online(i);
274 #endif
275
276         /*
277          * Initialize and free the full range of memory in each range.
278          * Note that the only writing these routines do are to the bootmap,
279          * and we've made sure to locate the bootmap properly so that they
280          * won't be writing over anything important.
281          */
282
283         bootmap_pfn = bootmap_start_pfn;
284         max_pfn = 0;
285         for (i = 0; i < npmem_ranges; i++) {
286                 unsigned long start_pfn;
287                 unsigned long npages;
288
289                 start_pfn = pmem_ranges[i].start_pfn;
290                 npages = pmem_ranges[i].pages;
291
292                 bootmap_size = init_bootmem_node(NODE_DATA(i),
293                                                 bootmap_pfn,
294                                                 start_pfn,
295                                                 (start_pfn + npages) );
296                 free_bootmem_node(NODE_DATA(i),
297                                   (start_pfn << PAGE_SHIFT),
298                                   (npages << PAGE_SHIFT) );
299                 bootmap_pfn += (bootmap_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
300                 if ((start_pfn + npages) > max_pfn)
301                         max_pfn = start_pfn + npages;
302         }
303
304         /* IOMMU is always used to access "high mem" on those boxes
305          * that can support enough mem that a PCI device couldn't
306          * directly DMA to any physical addresses.
307          * ISA DMA support will need to revisit this.
308          */
309         max_low_pfn = max_pfn;
310
311         if ((bootmap_pfn - bootmap_start_pfn) != bootmap_pages) {
312                 printk(KERN_WARNING "WARNING! bootmap sizing is messed up!\n");
313                 BUG();
314         }
315
316         /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
317
318 #define PDC_CONSOLE_IO_IODC_SIZE 32768
319
320         reserve_bootmem_node(NODE_DATA(0), 0UL,
321                         (unsigned long)(PAGE0->mem_free + PDC_CONSOLE_IO_IODC_SIZE));
322         reserve_bootmem_node(NODE_DATA(0),__pa((unsigned long)&_text),
323                         (unsigned long)(&_end - &_text));
324         reserve_bootmem_node(NODE_DATA(0), (bootmap_start_pfn << PAGE_SHIFT),
325                         ((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT));
326
327 #ifndef CONFIG_DISCONTIGMEM
328
329         /* reserve the holes */
330
331         for (i = 0; i < npmem_holes; i++) {
332                 reserve_bootmem_node(NODE_DATA(0),
333                                 (pmem_holes[i].start_pfn << PAGE_SHIFT),
334                                 (pmem_holes[i].pages << PAGE_SHIFT));
335         }
336 #endif
337
338 #ifdef CONFIG_BLK_DEV_INITRD
339         if (initrd_start) {
340                 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
341                 if (__pa(initrd_start) < mem_max) {
342                         unsigned long initrd_reserve;
343
344                         if (__pa(initrd_end) > mem_max) {
345                                 initrd_reserve = mem_max - __pa(initrd_start);
346                         } else {
347                                 initrd_reserve = initrd_end - initrd_start;
348                         }
349                         initrd_below_start_ok = 1;
350                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
351
352                         reserve_bootmem_node(NODE_DATA(0),__pa(initrd_start), initrd_reserve);
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         extern char __start_rodata, __end_rodata;
422         /* rodata memory was already mapped with KERNEL_RO access rights by
423            pagetable_init() and map_pages(). No need to do additional stuff here */
424         printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
425                 (unsigned long)(&__end_rodata - &__start_rodata) >> 10);
426 }
427 #endif
428
429
430 /*
431  * Just an arbitrary offset to serve as a "hole" between mapping areas
432  * (between top of physical memory and a potential pcxl dma mapping
433  * area, and below the vmalloc mapping area).
434  *
435  * The current 32K value just means that there will be a 32K "hole"
436  * between mapping areas. That means that  any out-of-bounds memory
437  * accesses will hopefully be caught. The vmalloc() routines leaves
438  * a hole of 4kB between each vmalloced area for the same reason.
439  */
440
441  /* Leave room for gateway page expansion */
442 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
443 #error KERNEL_MAP_START is in gateway reserved region
444 #endif
445 #define MAP_START (KERNEL_MAP_START)
446
447 #define VM_MAP_OFFSET  (32*1024)
448 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
449                                      & ~(VM_MAP_OFFSET-1)))
450
451 void *vmalloc_start __read_mostly;
452 EXPORT_SYMBOL(vmalloc_start);
453
454 #ifdef CONFIG_PA11
455 unsigned long pcxl_dma_start __read_mostly;
456 #endif
457
458 void __init mem_init(void)
459 {
460         high_memory = __va((max_pfn << PAGE_SHIFT));
461
462 #ifndef CONFIG_DISCONTIGMEM
463         max_mapnr = page_to_pfn(virt_to_page(high_memory - 1)) + 1;
464         totalram_pages += free_all_bootmem();
465 #else
466         {
467                 int i;
468
469                 for (i = 0; i < npmem_ranges; i++)
470                         totalram_pages += free_all_bootmem_node(NODE_DATA(i));
471         }
472 #endif
473
474         printk(KERN_INFO "Memory: %luk available\n", num_physpages << (PAGE_SHIFT-10));
475
476 #ifdef CONFIG_PA11
477         if (hppa_dma_ops == &pcxl_dma_ops) {
478                 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
479                 vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE);
480         } else {
481                 pcxl_dma_start = 0;
482                 vmalloc_start = SET_MAP_OFFSET(MAP_START);
483         }
484 #else
485         vmalloc_start = SET_MAP_OFFSET(MAP_START);
486 #endif
487
488 }
489
490 unsigned long *empty_zero_page __read_mostly;
491
492 void show_mem(void)
493 {
494         int i,free = 0,total = 0,reserved = 0;
495         int shared = 0, cached = 0;
496
497         printk(KERN_INFO "Mem-info:\n");
498         show_free_areas();
499         printk(KERN_INFO "Free swap:     %6ldkB\n",
500                                 nr_swap_pages<<(PAGE_SHIFT-10));
501 #ifndef CONFIG_DISCONTIGMEM
502         i = max_mapnr;
503         while (i-- > 0) {
504                 total++;
505                 if (PageReserved(mem_map+i))
506                         reserved++;
507                 else if (PageSwapCache(mem_map+i))
508                         cached++;
509                 else if (!page_count(&mem_map[i]))
510                         free++;
511                 else
512                         shared += page_count(&mem_map[i]) - 1;
513         }
514 #else
515         for (i = 0; i < npmem_ranges; i++) {
516                 int j;
517
518                 for (j = node_start_pfn(i); j < node_end_pfn(i); j++) {
519                         struct page *p;
520                         unsigned long flags;
521
522                         pgdat_resize_lock(NODE_DATA(i), &flags);
523                         p = nid_page_nr(i, j) - node_start_pfn(i);
524
525                         total++;
526                         if (PageReserved(p))
527                                 reserved++;
528                         else if (PageSwapCache(p))
529                                 cached++;
530                         else if (!page_count(p))
531                                 free++;
532                         else
533                                 shared += page_count(p) - 1;
534                         pgdat_resize_unlock(NODE_DATA(i), &flags);
535                 }
536         }
537 #endif
538         printk(KERN_INFO "%d pages of RAM\n", total);
539         printk(KERN_INFO "%d reserved pages\n", reserved);
540         printk(KERN_INFO "%d pages shared\n", shared);
541         printk(KERN_INFO "%d pages swap cached\n", cached);
542
543
544 #ifdef CONFIG_DISCONTIGMEM
545         {
546                 struct zonelist *zl;
547                 int i, j, k;
548
549                 for (i = 0; i < npmem_ranges; i++) {
550                         for (j = 0; j < MAX_NR_ZONES; j++) {
551                                 zl = NODE_DATA(i)->node_zonelists + j;
552
553                                 printk("Zone list for zone %d on node %d: ", j, i);
554                                 for (k = 0; zl->zones[k] != NULL; k++) 
555                                         printk("[%d/%s] ", zl->zones[k]->zone_pgdat->node_id, zl->zones[k]->name);
556                                 printk("\n");
557                         }
558                 }
559         }
560 #endif
561 }
562
563
564 static void __init map_pages(unsigned long start_vaddr, unsigned long start_paddr, unsigned long size, pgprot_t pgprot)
565 {
566         pgd_t *pg_dir;
567         pmd_t *pmd;
568         pte_t *pg_table;
569         unsigned long end_paddr;
570         unsigned long start_pmd;
571         unsigned long start_pte;
572         unsigned long tmp1;
573         unsigned long tmp2;
574         unsigned long address;
575         unsigned long ro_start;
576         unsigned long ro_end;
577         unsigned long fv_addr;
578         unsigned long gw_addr;
579         extern const unsigned long fault_vector_20;
580         extern void * const linux_gateway_page;
581
582         ro_start = __pa((unsigned long)&_text);
583         ro_end   = __pa((unsigned long)&data_start);
584         fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
585         gw_addr  = __pa((unsigned long)&linux_gateway_page) & PAGE_MASK;
586
587         end_paddr = start_paddr + size;
588
589         pg_dir = pgd_offset_k(start_vaddr);
590
591 #if PTRS_PER_PMD == 1
592         start_pmd = 0;
593 #else
594         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
595 #endif
596         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
597
598         address = start_paddr;
599         while (address < end_paddr) {
600 #if PTRS_PER_PMD == 1
601                 pmd = (pmd_t *)__pa(pg_dir);
602 #else
603                 pmd = (pmd_t *)pgd_address(*pg_dir);
604
605                 /*
606                  * pmd is physical at this point
607                  */
608
609                 if (!pmd) {
610                         pmd = (pmd_t *) alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE << PMD_ORDER);
611                         pmd = (pmd_t *) __pa(pmd);
612                 }
613
614                 pgd_populate(NULL, pg_dir, __va(pmd));
615 #endif
616                 pg_dir++;
617
618                 /* now change pmd to kernel virtual addresses */
619
620                 pmd = (pmd_t *)__va(pmd) + start_pmd;
621                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++,pmd++) {
622
623                         /*
624                          * pg_table is physical at this point
625                          */
626
627                         pg_table = (pte_t *)pmd_address(*pmd);
628                         if (!pg_table) {
629                                 pg_table = (pte_t *)
630                                         alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE);
631                                 pg_table = (pte_t *) __pa(pg_table);
632                         }
633
634                         pmd_populate_kernel(NULL, pmd, __va(pg_table));
635
636                         /* now change pg_table to kernel virtual addresses */
637
638                         pg_table = (pte_t *) __va(pg_table) + start_pte;
639                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++,pg_table++) {
640                                 pte_t pte;
641
642                                 /*
643                                  * Map the fault vector writable so we can
644                                  * write the HPMC checksum.
645                                  */
646 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
647                                 if (address >= ro_start && address < ro_end
648                                                         && address != fv_addr
649                                                         && address != gw_addr)
650                                     pte = __mk_pte(address, PAGE_KERNEL_RO);
651                                 else
652 #endif
653                                     pte = __mk_pte(address, pgprot);
654
655                                 if (address >= end_paddr)
656                                         pte_val(pte) = 0;
657
658                                 set_pte(pg_table, pte);
659
660                                 address += PAGE_SIZE;
661                         }
662                         start_pte = 0;
663
664                         if (address >= end_paddr)
665                             break;
666                 }
667                 start_pmd = 0;
668         }
669 }
670
671 /*
672  * pagetable_init() sets up the page tables
673  *
674  * Note that gateway_init() places the Linux gateway page at page 0.
675  * Since gateway pages cannot be dereferenced this has the desirable
676  * side effect of trapping those pesky NULL-reference errors in the
677  * kernel.
678  */
679 static void __init pagetable_init(void)
680 {
681         int range;
682
683         /* Map each physical memory range to its kernel vaddr */
684
685         for (range = 0; range < npmem_ranges; range++) {
686                 unsigned long start_paddr;
687                 unsigned long end_paddr;
688                 unsigned long size;
689
690                 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
691                 end_paddr = start_paddr + (pmem_ranges[range].pages << PAGE_SHIFT);
692                 size = pmem_ranges[range].pages << PAGE_SHIFT;
693
694                 map_pages((unsigned long)__va(start_paddr), start_paddr,
695                         size, PAGE_KERNEL);
696         }
697
698 #ifdef CONFIG_BLK_DEV_INITRD
699         if (initrd_end && initrd_end > mem_limit) {
700                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
701                 map_pages(initrd_start, __pa(initrd_start),
702                         initrd_end - initrd_start, PAGE_KERNEL);
703         }
704 #endif
705
706         empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
707         memset(empty_zero_page, 0, PAGE_SIZE);
708 }
709
710 static void __init gateway_init(void)
711 {
712         unsigned long linux_gateway_page_addr;
713         /* FIXME: This is 'const' in order to trick the compiler
714            into not treating it as DP-relative data. */
715         extern void * const linux_gateway_page;
716
717         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
718
719         /*
720          * Setup Linux Gateway page.
721          *
722          * The Linux gateway page will reside in kernel space (on virtual
723          * page 0), so it doesn't need to be aliased into user space.
724          */
725
726         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
727                 PAGE_SIZE, PAGE_GATEWAY);
728 }
729
730 #ifdef CONFIG_HPUX
731 void
732 map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm)
733 {
734         pgd_t *pg_dir;
735         pmd_t *pmd;
736         pte_t *pg_table;
737         unsigned long start_pmd;
738         unsigned long start_pte;
739         unsigned long address;
740         unsigned long hpux_gw_page_addr;
741         /* FIXME: This is 'const' in order to trick the compiler
742            into not treating it as DP-relative data. */
743         extern void * const hpux_gateway_page;
744
745         hpux_gw_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
746
747         /*
748          * Setup HP-UX Gateway page.
749          *
750          * The HP-UX gateway page resides in the user address space,
751          * so it needs to be aliased into each process.
752          */
753
754         pg_dir = pgd_offset(mm,hpux_gw_page_addr);
755
756 #if PTRS_PER_PMD == 1
757         start_pmd = 0;
758 #else
759         start_pmd = ((hpux_gw_page_addr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
760 #endif
761         start_pte = ((hpux_gw_page_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
762
763         address = __pa(&hpux_gateway_page);
764 #if PTRS_PER_PMD == 1
765         pmd = (pmd_t *)__pa(pg_dir);
766 #else
767         pmd = (pmd_t *) pgd_address(*pg_dir);
768
769         /*
770          * pmd is physical at this point
771          */
772
773         if (!pmd) {
774                 pmd = (pmd_t *) get_zeroed_page(GFP_KERNEL);
775                 pmd = (pmd_t *) __pa(pmd);
776         }
777
778         __pgd_val_set(*pg_dir, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pmd);
779 #endif
780         /* now change pmd to kernel virtual addresses */
781
782         pmd = (pmd_t *)__va(pmd) + start_pmd;
783
784         /*
785          * pg_table is physical at this point
786          */
787
788         pg_table = (pte_t *) pmd_address(*pmd);
789         if (!pg_table)
790                 pg_table = (pte_t *) __pa(get_zeroed_page(GFP_KERNEL));
791
792         __pmd_val_set(*pmd, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pg_table);
793
794         /* now change pg_table to kernel virtual addresses */
795
796         pg_table = (pte_t *) __va(pg_table) + start_pte;
797         set_pte(pg_table, __mk_pte(address, PAGE_GATEWAY));
798 }
799 EXPORT_SYMBOL(map_hpux_gateway_page);
800 #endif
801
802 void __init paging_init(void)
803 {
804         int i;
805
806         setup_bootmem();
807         pagetable_init();
808         gateway_init();
809         flush_cache_all_local(); /* start with known state */
810         flush_tlb_all_local(NULL);
811
812         for (i = 0; i < npmem_ranges; i++) {
813                 unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0 };
814
815                 /* We have an IOMMU, so all memory can go into a single
816                    ZONE_DMA zone. */
817                 zones_size[ZONE_DMA] = pmem_ranges[i].pages;
818
819 #ifdef CONFIG_DISCONTIGMEM
820                 /* Need to initialize the pfnnid_map before we can initialize
821                    the zone */
822                 {
823                     int j;
824                     for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
825                          j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
826                          j++) {
827                         pfnnid_map[j] = i;
828                     }
829                 }
830 #endif
831
832                 free_area_init_node(i, NODE_DATA(i), zones_size,
833                                 pmem_ranges[i].start_pfn, NULL);
834         }
835 }
836
837 #ifdef CONFIG_PA20
838
839 /*
840  * Currently, all PA20 chips have 18 bit protection id's, which is the
841  * limiting factor (space ids are 32 bits).
842  */
843
844 #define NR_SPACE_IDS 262144
845
846 #else
847
848 /*
849  * Currently we have a one-to-one relationship between space id's and
850  * protection id's. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
851  * support 15 bit protection id's, so that is the limiting factor.
852  * PCXT' has 18 bit protection id's, but only 16 bit spaceids, so it's
853  * probably not worth the effort for a special case here.
854  */
855
856 #define NR_SPACE_IDS 32768
857
858 #endif  /* !CONFIG_PA20 */
859
860 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
861 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
862
863 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
864 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
865 static unsigned long space_id_index;
866 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
867 static unsigned long dirty_space_ids = 0;
868
869 static DEFINE_SPINLOCK(sid_lock);
870
871 unsigned long alloc_sid(void)
872 {
873         unsigned long index;
874
875         spin_lock(&sid_lock);
876
877         if (free_space_ids == 0) {
878                 if (dirty_space_ids != 0) {
879                         spin_unlock(&sid_lock);
880                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
881                         spin_lock(&sid_lock);
882                 }
883                 BUG_ON(free_space_ids == 0);
884         }
885
886         free_space_ids--;
887
888         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
889         space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
890         space_id_index = index;
891
892         spin_unlock(&sid_lock);
893
894         return index << SPACEID_SHIFT;
895 }
896
897 void free_sid(unsigned long spaceid)
898 {
899         unsigned long index = spaceid >> SPACEID_SHIFT;
900         unsigned long *dirty_space_offset;
901
902         dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
903         index &= (BITS_PER_LONG - 1);
904
905         spin_lock(&sid_lock);
906
907         BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
908
909         *dirty_space_offset |= (1L << index);
910         dirty_space_ids++;
911
912         spin_unlock(&sid_lock);
913 }
914
915
916 #ifdef CONFIG_SMP
917 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
918 {
919         int i;
920
921         /* NOTE: sid_lock must be held upon entry */
922
923         *ndirtyptr = dirty_space_ids;
924         if (dirty_space_ids != 0) {
925             for (i = 0; i < SID_ARRAY_SIZE; i++) {
926                 dirty_array[i] = dirty_space_id[i];
927                 dirty_space_id[i] = 0;
928             }
929             dirty_space_ids = 0;
930         }
931
932         return;
933 }
934
935 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
936 {
937         int i;
938
939         /* NOTE: sid_lock must be held upon entry */
940
941         if (ndirty != 0) {
942                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
943                         space_id[i] ^= dirty_array[i];
944                 }
945
946                 free_space_ids += ndirty;
947                 space_id_index = 0;
948         }
949 }
950
951 #else /* CONFIG_SMP */
952
953 static void recycle_sids(void)
954 {
955         int i;
956
957         /* NOTE: sid_lock must be held upon entry */
958
959         if (dirty_space_ids != 0) {
960                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
961                         space_id[i] ^= dirty_space_id[i];
962                         dirty_space_id[i] = 0;
963                 }
964
965                 free_space_ids += dirty_space_ids;
966                 dirty_space_ids = 0;
967                 space_id_index = 0;
968         }
969 }
970 #endif
971
972 /*
973  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
974  * purged, we can safely reuse the space ids that were released but
975  * not flushed from the tlb.
976  */
977
978 #ifdef CONFIG_SMP
979
980 static unsigned long recycle_ndirty;
981 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
982 static unsigned int recycle_inuse;
983
984 void flush_tlb_all(void)
985 {
986         int do_recycle;
987
988         do_recycle = 0;
989         spin_lock(&sid_lock);
990         if (dirty_space_ids > RECYCLE_THRESHOLD) {
991             BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
992             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
993             recycle_inuse++;
994             do_recycle++;
995         }
996         spin_unlock(&sid_lock);
997         on_each_cpu(flush_tlb_all_local, NULL, 1, 1);
998         if (do_recycle) {
999             spin_lock(&sid_lock);
1000             recycle_sids(recycle_ndirty,recycle_dirty_array);
1001             recycle_inuse = 0;
1002             spin_unlock(&sid_lock);
1003         }
1004 }
1005 #else
1006 void flush_tlb_all(void)
1007 {
1008         spin_lock(&sid_lock);
1009         flush_tlb_all_local(NULL);
1010         recycle_sids();
1011         spin_unlock(&sid_lock);
1012 }
1013 #endif
1014
1015 #ifdef CONFIG_BLK_DEV_INITRD
1016 void free_initrd_mem(unsigned long start, unsigned long end)
1017 {
1018         if (start >= end)
1019                 return;
1020         printk(KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
1021         for (; start < end; start += PAGE_SIZE) {
1022                 ClearPageReserved(virt_to_page(start));
1023                 init_page_count(virt_to_page(start));
1024                 free_page(start);
1025                 num_physpages++;
1026                 totalram_pages++;
1027         }
1028 }
1029 #endif