7e7a3126c5e9669f4750a4ec51bf4c0917a60797
[linux-2.6-block.git] / arch / parisc / mm / init.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/arch/parisc/mm/init.c
4  *
5  *  Copyright (C) 1995  Linus Torvalds
6  *  Copyright 1999 SuSE GmbH
7  *    changed by Philipp Rumpf
8  *  Copyright 1999 Philipp Rumpf (prumpf@tux.org)
9  *  Copyright 2004 Randolph Chung (tausq@debian.org)
10  *  Copyright 2006-2007 Helge Deller (deller@gmx.de)
11  *
12  */
13
14
15 #include <linux/module.h>
16 #include <linux/mm.h>
17 #include <linux/bootmem.h>
18 #include <linux/memblock.h>
19 #include <linux/gfp.h>
20 #include <linux/delay.h>
21 #include <linux/init.h>
22 #include <linux/initrd.h>
23 #include <linux/swap.h>
24 #include <linux/unistd.h>
25 #include <linux/nodemask.h>     /* for node_online_map */
26 #include <linux/pagemap.h>      /* for release_pages */
27 #include <linux/compat.h>
28
29 #include <asm/pgalloc.h>
30 #include <asm/pgtable.h>
31 #include <asm/tlb.h>
32 #include <asm/pdc_chassis.h>
33 #include <asm/mmzone.h>
34 #include <asm/sections.h>
35 #include <asm/msgbuf.h>
36
37 extern int  data_start;
38 extern void parisc_kernel_start(void);  /* Kernel entry point in head.S */
39
40 #if CONFIG_PGTABLE_LEVELS == 3
41 /* NOTE: This layout exactly conforms to the hybrid L2/L3 page table layout
42  * with the first pmd adjacent to the pgd and below it. gcc doesn't actually
43  * guarantee that global objects will be laid out in memory in the same order
44  * as the order of declaration, so put these in different sections and use
45  * the linker script to order them. */
46 pmd_t pmd0[PTRS_PER_PMD] __attribute__ ((__section__ (".data..vm0.pmd"), aligned(PAGE_SIZE)));
47 #endif
48
49 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__ ((__section__ (".data..vm0.pgd"), aligned(PAGE_SIZE)));
50 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __attribute__ ((__section__ (".data..vm0.pte"), aligned(PAGE_SIZE)));
51
52 #ifdef CONFIG_DISCONTIGMEM
53 struct node_map_data node_data[MAX_NUMNODES] __read_mostly;
54 signed char pfnnid_map[PFNNID_MAP_MAX] __read_mostly;
55 #endif
56
57 static struct resource data_resource = {
58         .name   = "Kernel data",
59         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
60 };
61
62 static struct resource code_resource = {
63         .name   = "Kernel code",
64         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
65 };
66
67 static struct resource pdcdata_resource = {
68         .name   = "PDC data (Page Zero)",
69         .start  = 0,
70         .end    = 0x9ff,
71         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
72 };
73
74 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __read_mostly;
75
76 /* The following array is initialized from the firmware specific
77  * information retrieved in kernel/inventory.c.
78  */
79
80 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __read_mostly;
81 int npmem_ranges __read_mostly;
82
83 /*
84  * get_memblock() allocates pages via memblock.
85  * We can't use memblock_find_in_range(0, KERNEL_INITIAL_SIZE) here since it
86  * doesn't allocate from bottom to top which is needed because we only created
87  * the initial mapping up to KERNEL_INITIAL_SIZE in the assembly bootup code.
88  */
89 static void * __init get_memblock(unsigned long size)
90 {
91         static phys_addr_t search_addr __initdata;
92         phys_addr_t phys;
93
94         if (!search_addr)
95                 search_addr = PAGE_ALIGN(__pa((unsigned long) &_end));
96         search_addr = ALIGN(search_addr, size);
97         while (!memblock_is_region_memory(search_addr, size) ||
98                 memblock_is_region_reserved(search_addr, size)) {
99                 search_addr += size;
100         }
101         phys = search_addr;
102
103         if (phys)
104                 memblock_reserve(phys, size);
105         else
106                 panic("get_memblock() failed.\n");
107
108         memset(__va(phys), 0, size);
109
110         return __va(phys);
111 }
112
113 #ifdef CONFIG_64BIT
114 #define MAX_MEM         (~0UL)
115 #else /* !CONFIG_64BIT */
116 #define MAX_MEM         (3584U*1024U*1024U)
117 #endif /* !CONFIG_64BIT */
118
119 static unsigned long mem_limit __read_mostly = MAX_MEM;
120
121 static void __init mem_limit_func(void)
122 {
123         char *cp, *end;
124         unsigned long limit;
125
126         /* We need this before __setup() functions are called */
127
128         limit = MAX_MEM;
129         for (cp = boot_command_line; *cp; ) {
130                 if (memcmp(cp, "mem=", 4) == 0) {
131                         cp += 4;
132                         limit = memparse(cp, &end);
133                         if (end != cp)
134                                 break;
135                         cp = end;
136                 } else {
137                         while (*cp != ' ' && *cp)
138                                 ++cp;
139                         while (*cp == ' ')
140                                 ++cp;
141                 }
142         }
143
144         if (limit < mem_limit)
145                 mem_limit = limit;
146 }
147
148 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
149
150 static void __init setup_bootmem(void)
151 {
152         unsigned long mem_max;
153 #ifndef CONFIG_DISCONTIGMEM
154         physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
155         int npmem_holes;
156 #endif
157         int i, sysram_resource_count;
158
159         disable_sr_hashing(); /* Turn off space register hashing */
160
161         /*
162          * Sort the ranges. Since the number of ranges is typically
163          * small, and performance is not an issue here, just do
164          * a simple insertion sort.
165          */
166
167         for (i = 1; i < npmem_ranges; i++) {
168                 int j;
169
170                 for (j = i; j > 0; j--) {
171                         unsigned long tmp;
172
173                         if (pmem_ranges[j-1].start_pfn <
174                             pmem_ranges[j].start_pfn) {
175
176                                 break;
177                         }
178                         tmp = pmem_ranges[j-1].start_pfn;
179                         pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn;
180                         pmem_ranges[j].start_pfn = tmp;
181                         tmp = pmem_ranges[j-1].pages;
182                         pmem_ranges[j-1].pages = pmem_ranges[j].pages;
183                         pmem_ranges[j].pages = tmp;
184                 }
185         }
186
187 #ifndef CONFIG_DISCONTIGMEM
188         /*
189          * Throw out ranges that are too far apart (controlled by
190          * MAX_GAP).
191          */
192
193         for (i = 1; i < npmem_ranges; i++) {
194                 if (pmem_ranges[i].start_pfn -
195                         (pmem_ranges[i-1].start_pfn +
196                          pmem_ranges[i-1].pages) > MAX_GAP) {
197                         npmem_ranges = i;
198                         printk("Large gap in memory detected (%ld pages). "
199                                "Consider turning on CONFIG_DISCONTIGMEM\n",
200                                pmem_ranges[i].start_pfn -
201                                (pmem_ranges[i-1].start_pfn +
202                                 pmem_ranges[i-1].pages));
203                         break;
204                 }
205         }
206 #endif
207
208         /* Print the memory ranges */
209         pr_info("Memory Ranges:\n");
210
211         for (i = 0; i < npmem_ranges; i++) {
212                 struct resource *res = &sysram_resources[i];
213                 unsigned long start;
214                 unsigned long size;
215
216                 size = (pmem_ranges[i].pages << PAGE_SHIFT);
217                 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
218                 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
219                         i, start, start + (size - 1), size >> 20);
220
221                 /* request memory resource */
222                 res->name = "System RAM";
223                 res->start = start;
224                 res->end = start + size - 1;
225                 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
226                 request_resource(&iomem_resource, res);
227         }
228
229         sysram_resource_count = npmem_ranges;
230
231         /*
232          * For 32 bit kernels we limit the amount of memory we can
233          * support, in order to preserve enough kernel address space
234          * for other purposes. For 64 bit kernels we don't normally
235          * limit the memory, but this mechanism can be used to
236          * artificially limit the amount of memory (and it is written
237          * to work with multiple memory ranges).
238          */
239
240         mem_limit_func();       /* check for "mem=" argument */
241
242         mem_max = 0;
243         for (i = 0; i < npmem_ranges; i++) {
244                 unsigned long rsize;
245
246                 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
247                 if ((mem_max + rsize) > mem_limit) {
248                         printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
249                         if (mem_max == mem_limit)
250                                 npmem_ranges = i;
251                         else {
252                                 pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
253                                                        - (mem_max >> PAGE_SHIFT);
254                                 npmem_ranges = i + 1;
255                                 mem_max = mem_limit;
256                         }
257                         break;
258                 }
259                 mem_max += rsize;
260         }
261
262         printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
263
264 #ifndef CONFIG_DISCONTIGMEM
265         /* Merge the ranges, keeping track of the holes */
266
267         {
268                 unsigned long end_pfn;
269                 unsigned long hole_pages;
270
271                 npmem_holes = 0;
272                 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
273                 for (i = 1; i < npmem_ranges; i++) {
274
275                         hole_pages = pmem_ranges[i].start_pfn - end_pfn;
276                         if (hole_pages) {
277                                 pmem_holes[npmem_holes].start_pfn = end_pfn;
278                                 pmem_holes[npmem_holes++].pages = hole_pages;
279                                 end_pfn += hole_pages;
280                         }
281                         end_pfn += pmem_ranges[i].pages;
282                 }
283
284                 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
285                 npmem_ranges = 1;
286         }
287 #endif
288
289 #ifdef CONFIG_DISCONTIGMEM
290         for (i = 0; i < MAX_PHYSMEM_RANGES; i++) {
291                 memset(NODE_DATA(i), 0, sizeof(pg_data_t));
292         }
293         memset(pfnnid_map, 0xff, sizeof(pfnnid_map));
294
295         for (i = 0; i < npmem_ranges; i++) {
296                 node_set_state(i, N_NORMAL_MEMORY);
297                 node_set_online(i);
298         }
299 #endif
300
301         /*
302          * Initialize and free the full range of memory in each range.
303          */
304
305         max_pfn = 0;
306         for (i = 0; i < npmem_ranges; i++) {
307                 unsigned long start_pfn;
308                 unsigned long npages;
309                 unsigned long start;
310                 unsigned long size;
311
312                 start_pfn = pmem_ranges[i].start_pfn;
313                 npages = pmem_ranges[i].pages;
314
315                 start = start_pfn << PAGE_SHIFT;
316                 size = npages << PAGE_SHIFT;
317
318                 /* add system RAM memblock */
319                 memblock_add(start, size);
320
321                 if ((start_pfn + npages) > max_pfn)
322                         max_pfn = start_pfn + npages;
323         }
324
325         /* IOMMU is always used to access "high mem" on those boxes
326          * that can support enough mem that a PCI device couldn't
327          * directly DMA to any physical addresses.
328          * ISA DMA support will need to revisit this.
329          */
330         max_low_pfn = max_pfn;
331
332         /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
333
334 #define PDC_CONSOLE_IO_IODC_SIZE 32768
335
336         memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
337                                 PDC_CONSOLE_IO_IODC_SIZE));
338         memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
339                         (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
340
341 #ifndef CONFIG_DISCONTIGMEM
342
343         /* reserve the holes */
344
345         for (i = 0; i < npmem_holes; i++) {
346                 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
347                                 (pmem_holes[i].pages << PAGE_SHIFT));
348         }
349 #endif
350
351 #ifdef CONFIG_BLK_DEV_INITRD
352         if (initrd_start) {
353                 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
354                 if (__pa(initrd_start) < mem_max) {
355                         unsigned long initrd_reserve;
356
357                         if (__pa(initrd_end) > mem_max) {
358                                 initrd_reserve = mem_max - __pa(initrd_start);
359                         } else {
360                                 initrd_reserve = initrd_end - initrd_start;
361                         }
362                         initrd_below_start_ok = 1;
363                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
364
365                         memblock_reserve(__pa(initrd_start), initrd_reserve);
366                 }
367         }
368 #endif
369
370         data_resource.start =  virt_to_phys(&data_start);
371         data_resource.end = virt_to_phys(_end) - 1;
372         code_resource.start = virt_to_phys(_text);
373         code_resource.end = virt_to_phys(&data_start)-1;
374
375         /* We don't know which region the kernel will be in, so try
376          * all of them.
377          */
378         for (i = 0; i < sysram_resource_count; i++) {
379                 struct resource *res = &sysram_resources[i];
380                 request_resource(res, &code_resource);
381                 request_resource(res, &data_resource);
382         }
383         request_resource(&sysram_resources[0], &pdcdata_resource);
384
385         /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
386         pdc_pdt_init();
387 }
388
389 static int __init parisc_text_address(unsigned long vaddr)
390 {
391         static unsigned long head_ptr __initdata;
392
393         if (!head_ptr)
394                 head_ptr = PAGE_MASK & (unsigned long)
395                         dereference_function_descriptor(&parisc_kernel_start);
396
397         return core_kernel_text(vaddr) || vaddr == head_ptr;
398 }
399
400 static void __init map_pages(unsigned long start_vaddr,
401                              unsigned long start_paddr, unsigned long size,
402                              pgprot_t pgprot, int force)
403 {
404         pgd_t *pg_dir;
405         pmd_t *pmd;
406         pte_t *pg_table;
407         unsigned long end_paddr;
408         unsigned long start_pmd;
409         unsigned long start_pte;
410         unsigned long tmp1;
411         unsigned long tmp2;
412         unsigned long address;
413         unsigned long vaddr;
414         unsigned long ro_start;
415         unsigned long ro_end;
416         unsigned long kernel_end;
417
418         ro_start = __pa((unsigned long)_text);
419         ro_end   = __pa((unsigned long)&data_start);
420         kernel_end  = __pa((unsigned long)&_end);
421
422         end_paddr = start_paddr + size;
423
424         pg_dir = pgd_offset_k(start_vaddr);
425
426 #if PTRS_PER_PMD == 1
427         start_pmd = 0;
428 #else
429         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
430 #endif
431         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
432
433         address = start_paddr;
434         vaddr = start_vaddr;
435         while (address < end_paddr) {
436 #if PTRS_PER_PMD == 1
437                 pmd = (pmd_t *)__pa(pg_dir);
438 #else
439                 pmd = (pmd_t *)pgd_address(*pg_dir);
440
441                 /*
442                  * pmd is physical at this point
443                  */
444
445                 if (!pmd) {
446                         pmd = (pmd_t *) get_memblock(PAGE_SIZE << PMD_ORDER);
447                         pmd = (pmd_t *) __pa(pmd);
448                 }
449
450                 pgd_populate(NULL, pg_dir, __va(pmd));
451 #endif
452                 pg_dir++;
453
454                 /* now change pmd to kernel virtual addresses */
455
456                 pmd = (pmd_t *)__va(pmd) + start_pmd;
457                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
458
459                         /*
460                          * pg_table is physical at this point
461                          */
462
463                         pg_table = (pte_t *)pmd_address(*pmd);
464                         if (!pg_table) {
465                                 pg_table = (pte_t *) get_memblock(PAGE_SIZE);
466                                 pg_table = (pte_t *) __pa(pg_table);
467                         }
468
469                         pmd_populate_kernel(NULL, pmd, __va(pg_table));
470
471                         /* now change pg_table to kernel virtual addresses */
472
473                         pg_table = (pte_t *) __va(pg_table) + start_pte;
474                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
475                                 pte_t pte;
476
477                                 if (force)
478                                         pte =  __mk_pte(address, pgprot);
479                                 else if (parisc_text_address(vaddr)) {
480                                         pte = __mk_pte(address, PAGE_KERNEL_EXEC);
481                                         if (address >= ro_start && address < kernel_end)
482                                                 pte = pte_mkhuge(pte);
483                                 }
484                                 else
485 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
486                                 if (address >= ro_start && address < ro_end) {
487                                         pte = __mk_pte(address, PAGE_KERNEL_EXEC);
488                                         pte = pte_mkhuge(pte);
489                                 } else
490 #endif
491                                 {
492                                         pte = __mk_pte(address, pgprot);
493                                         if (address >= ro_start && address < kernel_end)
494                                                 pte = pte_mkhuge(pte);
495                                 }
496
497                                 if (address >= end_paddr)
498                                         break;
499
500                                 set_pte(pg_table, pte);
501
502                                 address += PAGE_SIZE;
503                                 vaddr += PAGE_SIZE;
504                         }
505                         start_pte = 0;
506
507                         if (address >= end_paddr)
508                             break;
509                 }
510                 start_pmd = 0;
511         }
512 }
513
514 void __init set_kernel_text_rw(int enable_read_write)
515 {
516         unsigned long start = (unsigned long)__init_begin;
517         unsigned long end   = (unsigned long)_etext;
518
519         map_pages(start, __pa(start), end-start,
520                 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
521
522         /* force the kernel to see the new page table entries */
523         flush_cache_all();
524         flush_tlb_all();
525 }
526
527 void __ref free_initmem(void)
528 {
529         unsigned long init_begin = (unsigned long)__init_begin;
530         unsigned long init_end = (unsigned long)__init_end;
531
532         /* The init text pages are marked R-X.  We have to
533          * flush the icache and mark them RW-
534          *
535          * This is tricky, because map_pages is in the init section.
536          * Do a dummy remap of the data section first (the data
537          * section is already PAGE_KERNEL) to pull in the TLB entries
538          * for map_kernel */
539         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
540                   PAGE_KERNEL_RWX, 1);
541         /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
542          * map_pages */
543         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
544                   PAGE_KERNEL, 1);
545
546         /* force the kernel to see the new TLB entries */
547         __flush_tlb_range(0, init_begin, init_end);
548
549         /* finally dump all the instructions which were cached, since the
550          * pages are no-longer executable */
551         flush_icache_range(init_begin, init_end);
552         
553         free_initmem_default(POISON_FREE_INITMEM);
554
555         /* set up a new led state on systems shipped LED State panel */
556         pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
557 }
558
559
560 #ifdef CONFIG_STRICT_KERNEL_RWX
561 void mark_rodata_ro(void)
562 {
563         /* rodata memory was already mapped with KERNEL_RO access rights by
564            pagetable_init() and map_pages(). No need to do additional stuff here */
565         printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
566                 (unsigned long)(__end_rodata - __start_rodata) >> 10);
567 }
568 #endif
569
570
571 /*
572  * Just an arbitrary offset to serve as a "hole" between mapping areas
573  * (between top of physical memory and a potential pcxl dma mapping
574  * area, and below the vmalloc mapping area).
575  *
576  * The current 32K value just means that there will be a 32K "hole"
577  * between mapping areas. That means that  any out-of-bounds memory
578  * accesses will hopefully be caught. The vmalloc() routines leaves
579  * a hole of 4kB between each vmalloced area for the same reason.
580  */
581
582  /* Leave room for gateway page expansion */
583 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
584 #error KERNEL_MAP_START is in gateway reserved region
585 #endif
586 #define MAP_START (KERNEL_MAP_START)
587
588 #define VM_MAP_OFFSET  (32*1024)
589 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
590                                      & ~(VM_MAP_OFFSET-1)))
591
592 void *parisc_vmalloc_start __read_mostly;
593 EXPORT_SYMBOL(parisc_vmalloc_start);
594
595 #ifdef CONFIG_PA11
596 unsigned long pcxl_dma_start __read_mostly;
597 #endif
598
599 void __init mem_init(void)
600 {
601         /* Do sanity checks on IPC (compat) structures */
602         BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
603 #ifndef CONFIG_64BIT
604         BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
605         BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
606         BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
607 #endif
608 #ifdef CONFIG_COMPAT
609         BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
610         BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
611         BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
612         BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
613 #endif
614
615         /* Do sanity checks on page table constants */
616         BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
617         BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
618         BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
619         BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
620                         > BITS_PER_LONG);
621
622         high_memory = __va((max_pfn << PAGE_SHIFT));
623         set_max_mapnr(page_to_pfn(virt_to_page(high_memory - 1)) + 1);
624         memblock_free_all();
625
626 #ifdef CONFIG_PA11
627         if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
628                 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
629                 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
630                                                 + PCXL_DMA_MAP_SIZE);
631         } else
632 #endif
633                 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
634
635         mem_init_print_info(NULL);
636
637 #if 0
638         /*
639          * Do not expose the virtual kernel memory layout to userspace.
640          * But keep code for debugging purposes.
641          */
642         printk("virtual kernel memory layout:\n"
643                "    vmalloc : 0x%px - 0x%px   (%4ld MB)\n"
644                "    memory  : 0x%px - 0x%px   (%4ld MB)\n"
645                "      .init : 0x%px - 0x%px   (%4ld kB)\n"
646                "      .data : 0x%px - 0x%px   (%4ld kB)\n"
647                "      .text : 0x%px - 0x%px   (%4ld kB)\n",
648
649                (void*)VMALLOC_START, (void*)VMALLOC_END,
650                (VMALLOC_END - VMALLOC_START) >> 20,
651
652                __va(0), high_memory,
653                ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
654
655                __init_begin, __init_end,
656                ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
657
658                _etext, _edata,
659                ((unsigned long)_edata - (unsigned long)_etext) >> 10,
660
661                _text, _etext,
662                ((unsigned long)_etext - (unsigned long)_text) >> 10);
663 #endif
664 }
665
666 unsigned long *empty_zero_page __read_mostly;
667 EXPORT_SYMBOL(empty_zero_page);
668
669 /*
670  * pagetable_init() sets up the page tables
671  *
672  * Note that gateway_init() places the Linux gateway page at page 0.
673  * Since gateway pages cannot be dereferenced this has the desirable
674  * side effect of trapping those pesky NULL-reference errors in the
675  * kernel.
676  */
677 static void __init pagetable_init(void)
678 {
679         int range;
680
681         /* Map each physical memory range to its kernel vaddr */
682
683         for (range = 0; range < npmem_ranges; range++) {
684                 unsigned long start_paddr;
685                 unsigned long end_paddr;
686                 unsigned long size;
687
688                 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
689                 size = pmem_ranges[range].pages << PAGE_SHIFT;
690                 end_paddr = start_paddr + size;
691
692                 map_pages((unsigned long)__va(start_paddr), start_paddr,
693                           size, PAGE_KERNEL, 0);
694         }
695
696 #ifdef CONFIG_BLK_DEV_INITRD
697         if (initrd_end && initrd_end > mem_limit) {
698                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
699                 map_pages(initrd_start, __pa(initrd_start),
700                           initrd_end - initrd_start, PAGE_KERNEL, 0);
701         }
702 #endif
703
704         empty_zero_page = get_memblock(PAGE_SIZE);
705 }
706
707 static void __init gateway_init(void)
708 {
709         unsigned long linux_gateway_page_addr;
710         /* FIXME: This is 'const' in order to trick the compiler
711            into not treating it as DP-relative data. */
712         extern void * const linux_gateway_page;
713
714         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
715
716         /*
717          * Setup Linux Gateway page.
718          *
719          * The Linux gateway page will reside in kernel space (on virtual
720          * page 0), so it doesn't need to be aliased into user space.
721          */
722
723         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
724                   PAGE_SIZE, PAGE_GATEWAY, 1);
725 }
726
727 void __init paging_init(void)
728 {
729         int i;
730
731         setup_bootmem();
732         pagetable_init();
733         gateway_init();
734         flush_cache_all_local(); /* start with known state */
735         flush_tlb_all_local(NULL);
736
737         for (i = 0; i < npmem_ranges; i++) {
738                 unsigned long zones_size[MAX_NR_ZONES] = { 0, };
739
740                 zones_size[ZONE_NORMAL] = pmem_ranges[i].pages;
741
742 #ifdef CONFIG_DISCONTIGMEM
743                 /* Need to initialize the pfnnid_map before we can initialize
744                    the zone */
745                 {
746                     int j;
747                     for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
748                          j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
749                          j++) {
750                         pfnnid_map[j] = i;
751                     }
752                 }
753 #endif
754
755                 free_area_init_node(i, zones_size,
756                                 pmem_ranges[i].start_pfn, NULL);
757         }
758 }
759
760 #ifdef CONFIG_PA20
761
762 /*
763  * Currently, all PA20 chips have 18 bit protection IDs, which is the
764  * limiting factor (space ids are 32 bits).
765  */
766
767 #define NR_SPACE_IDS 262144
768
769 #else
770
771 /*
772  * Currently we have a one-to-one relationship between space IDs and
773  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
774  * support 15 bit protection IDs, so that is the limiting factor.
775  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
776  * probably not worth the effort for a special case here.
777  */
778
779 #define NR_SPACE_IDS 32768
780
781 #endif  /* !CONFIG_PA20 */
782
783 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
784 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
785
786 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
787 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
788 static unsigned long space_id_index;
789 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
790 static unsigned long dirty_space_ids = 0;
791
792 static DEFINE_SPINLOCK(sid_lock);
793
794 unsigned long alloc_sid(void)
795 {
796         unsigned long index;
797
798         spin_lock(&sid_lock);
799
800         if (free_space_ids == 0) {
801                 if (dirty_space_ids != 0) {
802                         spin_unlock(&sid_lock);
803                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
804                         spin_lock(&sid_lock);
805                 }
806                 BUG_ON(free_space_ids == 0);
807         }
808
809         free_space_ids--;
810
811         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
812         space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
813         space_id_index = index;
814
815         spin_unlock(&sid_lock);
816
817         return index << SPACEID_SHIFT;
818 }
819
820 void free_sid(unsigned long spaceid)
821 {
822         unsigned long index = spaceid >> SPACEID_SHIFT;
823         unsigned long *dirty_space_offset;
824
825         dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
826         index &= (BITS_PER_LONG - 1);
827
828         spin_lock(&sid_lock);
829
830         BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
831
832         *dirty_space_offset |= (1L << index);
833         dirty_space_ids++;
834
835         spin_unlock(&sid_lock);
836 }
837
838
839 #ifdef CONFIG_SMP
840 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
841 {
842         int i;
843
844         /* NOTE: sid_lock must be held upon entry */
845
846         *ndirtyptr = dirty_space_ids;
847         if (dirty_space_ids != 0) {
848             for (i = 0; i < SID_ARRAY_SIZE; i++) {
849                 dirty_array[i] = dirty_space_id[i];
850                 dirty_space_id[i] = 0;
851             }
852             dirty_space_ids = 0;
853         }
854
855         return;
856 }
857
858 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
859 {
860         int i;
861
862         /* NOTE: sid_lock must be held upon entry */
863
864         if (ndirty != 0) {
865                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
866                         space_id[i] ^= dirty_array[i];
867                 }
868
869                 free_space_ids += ndirty;
870                 space_id_index = 0;
871         }
872 }
873
874 #else /* CONFIG_SMP */
875
876 static void recycle_sids(void)
877 {
878         int i;
879
880         /* NOTE: sid_lock must be held upon entry */
881
882         if (dirty_space_ids != 0) {
883                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
884                         space_id[i] ^= dirty_space_id[i];
885                         dirty_space_id[i] = 0;
886                 }
887
888                 free_space_ids += dirty_space_ids;
889                 dirty_space_ids = 0;
890                 space_id_index = 0;
891         }
892 }
893 #endif
894
895 /*
896  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
897  * purged, we can safely reuse the space ids that were released but
898  * not flushed from the tlb.
899  */
900
901 #ifdef CONFIG_SMP
902
903 static unsigned long recycle_ndirty;
904 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
905 static unsigned int recycle_inuse;
906
907 void flush_tlb_all(void)
908 {
909         int do_recycle;
910
911         __inc_irq_stat(irq_tlb_count);
912         do_recycle = 0;
913         spin_lock(&sid_lock);
914         if (dirty_space_ids > RECYCLE_THRESHOLD) {
915             BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
916             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
917             recycle_inuse++;
918             do_recycle++;
919         }
920         spin_unlock(&sid_lock);
921         on_each_cpu(flush_tlb_all_local, NULL, 1);
922         if (do_recycle) {
923             spin_lock(&sid_lock);
924             recycle_sids(recycle_ndirty,recycle_dirty_array);
925             recycle_inuse = 0;
926             spin_unlock(&sid_lock);
927         }
928 }
929 #else
930 void flush_tlb_all(void)
931 {
932         __inc_irq_stat(irq_tlb_count);
933         spin_lock(&sid_lock);
934         flush_tlb_all_local(NULL);
935         recycle_sids();
936         spin_unlock(&sid_lock);
937 }
938 #endif
939
940 #ifdef CONFIG_BLK_DEV_INITRD
941 void free_initrd_mem(unsigned long start, unsigned long end)
942 {
943         free_reserved_area((void *)start, (void *)end, -1, "initrd");
944 }
945 #endif