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[linux.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/memblock.h>
18 #include <linux/gfp.h>
19 #include <linux/delay.h>
20 #include <linux/init.h>
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 */
26 #include <linux/compat.h>
27
28 #include <asm/pgalloc.h>
29 #include <asm/pgtable.h>
30 #include <asm/tlb.h>
31 #include <asm/pdc_chassis.h>
32 #include <asm/mmzone.h>
33 #include <asm/sections.h>
34 #include <asm/msgbuf.h>
35 #include <asm/sparsemem.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 static struct resource data_resource = {
53         .name   = "Kernel data",
54         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
55 };
56
57 static struct resource code_resource = {
58         .name   = "Kernel code",
59         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
60 };
61
62 static struct resource pdcdata_resource = {
63         .name   = "PDC data (Page Zero)",
64         .start  = 0,
65         .end    = 0x9ff,
66         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
67 };
68
69 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init;
70
71 /* The following array is initialized from the firmware specific
72  * information retrieved in kernel/inventory.c.
73  */
74
75 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata;
76 int npmem_ranges __initdata;
77
78 #ifdef CONFIG_64BIT
79 #define MAX_MEM         (1UL << MAX_PHYSMEM_BITS)
80 #else /* !CONFIG_64BIT */
81 #define MAX_MEM         (3584U*1024U*1024U)
82 #endif /* !CONFIG_64BIT */
83
84 static unsigned long mem_limit __read_mostly = MAX_MEM;
85
86 static void __init mem_limit_func(void)
87 {
88         char *cp, *end;
89         unsigned long limit;
90
91         /* We need this before __setup() functions are called */
92
93         limit = MAX_MEM;
94         for (cp = boot_command_line; *cp; ) {
95                 if (memcmp(cp, "mem=", 4) == 0) {
96                         cp += 4;
97                         limit = memparse(cp, &end);
98                         if (end != cp)
99                                 break;
100                         cp = end;
101                 } else {
102                         while (*cp != ' ' && *cp)
103                                 ++cp;
104                         while (*cp == ' ')
105                                 ++cp;
106                 }
107         }
108
109         if (limit < mem_limit)
110                 mem_limit = limit;
111 }
112
113 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
114
115 static void __init setup_bootmem(void)
116 {
117         unsigned long mem_max;
118 #ifndef CONFIG_SPARSEMEM
119         physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
120         int npmem_holes;
121 #endif
122         int i, sysram_resource_count;
123
124         disable_sr_hashing(); /* Turn off space register hashing */
125
126         /*
127          * Sort the ranges. Since the number of ranges is typically
128          * small, and performance is not an issue here, just do
129          * a simple insertion sort.
130          */
131
132         for (i = 1; i < npmem_ranges; i++) {
133                 int j;
134
135                 for (j = i; j > 0; j--) {
136                         physmem_range_t tmp;
137
138                         if (pmem_ranges[j-1].start_pfn <
139                             pmem_ranges[j].start_pfn) {
140
141                                 break;
142                         }
143                         tmp = pmem_ranges[j-1];
144                         pmem_ranges[j-1] = pmem_ranges[j];
145                         pmem_ranges[j] = tmp;
146                 }
147         }
148
149 #ifndef CONFIG_SPARSEMEM
150         /*
151          * Throw out ranges that are too far apart (controlled by
152          * MAX_GAP).
153          */
154
155         for (i = 1; i < npmem_ranges; i++) {
156                 if (pmem_ranges[i].start_pfn -
157                         (pmem_ranges[i-1].start_pfn +
158                          pmem_ranges[i-1].pages) > MAX_GAP) {
159                         npmem_ranges = i;
160                         printk("Large gap in memory detected (%ld pages). "
161                                "Consider turning on CONFIG_SPARSEMEM\n",
162                                pmem_ranges[i].start_pfn -
163                                (pmem_ranges[i-1].start_pfn +
164                                 pmem_ranges[i-1].pages));
165                         break;
166                 }
167         }
168 #endif
169
170         /* Print the memory ranges */
171         pr_info("Memory Ranges:\n");
172
173         for (i = 0; i < npmem_ranges; i++) {
174                 struct resource *res = &sysram_resources[i];
175                 unsigned long start;
176                 unsigned long size;
177
178                 size = (pmem_ranges[i].pages << PAGE_SHIFT);
179                 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
180                 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
181                         i, start, start + (size - 1), size >> 20);
182
183                 /* request memory resource */
184                 res->name = "System RAM";
185                 res->start = start;
186                 res->end = start + size - 1;
187                 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
188                 request_resource(&iomem_resource, res);
189         }
190
191         sysram_resource_count = npmem_ranges;
192
193         /*
194          * For 32 bit kernels we limit the amount of memory we can
195          * support, in order to preserve enough kernel address space
196          * for other purposes. For 64 bit kernels we don't normally
197          * limit the memory, but this mechanism can be used to
198          * artificially limit the amount of memory (and it is written
199          * to work with multiple memory ranges).
200          */
201
202         mem_limit_func();       /* check for "mem=" argument */
203
204         mem_max = 0;
205         for (i = 0; i < npmem_ranges; i++) {
206                 unsigned long rsize;
207
208                 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
209                 if ((mem_max + rsize) > mem_limit) {
210                         printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
211                         if (mem_max == mem_limit)
212                                 npmem_ranges = i;
213                         else {
214                                 pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
215                                                        - (mem_max >> PAGE_SHIFT);
216                                 npmem_ranges = i + 1;
217                                 mem_max = mem_limit;
218                         }
219                         break;
220                 }
221                 mem_max += rsize;
222         }
223
224         printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
225
226 #ifndef CONFIG_SPARSEMEM
227         /* Merge the ranges, keeping track of the holes */
228         {
229                 unsigned long end_pfn;
230                 unsigned long hole_pages;
231
232                 npmem_holes = 0;
233                 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
234                 for (i = 1; i < npmem_ranges; i++) {
235
236                         hole_pages = pmem_ranges[i].start_pfn - end_pfn;
237                         if (hole_pages) {
238                                 pmem_holes[npmem_holes].start_pfn = end_pfn;
239                                 pmem_holes[npmem_holes++].pages = hole_pages;
240                                 end_pfn += hole_pages;
241                         }
242                         end_pfn += pmem_ranges[i].pages;
243                 }
244
245                 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
246                 npmem_ranges = 1;
247         }
248 #endif
249
250         /*
251          * Initialize and free the full range of memory in each range.
252          */
253
254         max_pfn = 0;
255         for (i = 0; i < npmem_ranges; i++) {
256                 unsigned long start_pfn;
257                 unsigned long npages;
258                 unsigned long start;
259                 unsigned long size;
260
261                 start_pfn = pmem_ranges[i].start_pfn;
262                 npages = pmem_ranges[i].pages;
263
264                 start = start_pfn << PAGE_SHIFT;
265                 size = npages << PAGE_SHIFT;
266
267                 /* add system RAM memblock */
268                 memblock_add(start, size);
269
270                 if ((start_pfn + npages) > max_pfn)
271                         max_pfn = start_pfn + npages;
272         }
273
274         /*
275          * We can't use memblock top-down allocations because we only
276          * created the initial mapping up to KERNEL_INITIAL_SIZE in
277          * the assembly bootup code.
278          */
279         memblock_set_bottom_up(true);
280
281         /* IOMMU is always used to access "high mem" on those boxes
282          * that can support enough mem that a PCI device couldn't
283          * directly DMA to any physical addresses.
284          * ISA DMA support will need to revisit this.
285          */
286         max_low_pfn = max_pfn;
287
288         /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
289
290 #define PDC_CONSOLE_IO_IODC_SIZE 32768
291
292         memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
293                                 PDC_CONSOLE_IO_IODC_SIZE));
294         memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
295                         (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
296
297 #ifndef CONFIG_SPARSEMEM
298
299         /* reserve the holes */
300
301         for (i = 0; i < npmem_holes; i++) {
302                 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
303                                 (pmem_holes[i].pages << PAGE_SHIFT));
304         }
305 #endif
306
307 #ifdef CONFIG_BLK_DEV_INITRD
308         if (initrd_start) {
309                 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
310                 if (__pa(initrd_start) < mem_max) {
311                         unsigned long initrd_reserve;
312
313                         if (__pa(initrd_end) > mem_max) {
314                                 initrd_reserve = mem_max - __pa(initrd_start);
315                         } else {
316                                 initrd_reserve = initrd_end - initrd_start;
317                         }
318                         initrd_below_start_ok = 1;
319                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
320
321                         memblock_reserve(__pa(initrd_start), initrd_reserve);
322                 }
323         }
324 #endif
325
326         data_resource.start =  virt_to_phys(&data_start);
327         data_resource.end = virt_to_phys(_end) - 1;
328         code_resource.start = virt_to_phys(_text);
329         code_resource.end = virt_to_phys(&data_start)-1;
330
331         /* We don't know which region the kernel will be in, so try
332          * all of them.
333          */
334         for (i = 0; i < sysram_resource_count; i++) {
335                 struct resource *res = &sysram_resources[i];
336                 request_resource(res, &code_resource);
337                 request_resource(res, &data_resource);
338         }
339         request_resource(&sysram_resources[0], &pdcdata_resource);
340
341         /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
342         pdc_pdt_init();
343
344         memblock_allow_resize();
345         memblock_dump_all();
346 }
347
348 static bool kernel_set_to_readonly;
349
350 static void __init map_pages(unsigned long start_vaddr,
351                              unsigned long start_paddr, unsigned long size,
352                              pgprot_t pgprot, int force)
353 {
354         pmd_t *pmd;
355         pte_t *pg_table;
356         unsigned long end_paddr;
357         unsigned long start_pmd;
358         unsigned long start_pte;
359         unsigned long tmp1;
360         unsigned long tmp2;
361         unsigned long address;
362         unsigned long vaddr;
363         unsigned long ro_start;
364         unsigned long ro_end;
365         unsigned long kernel_start, kernel_end;
366
367         ro_start = __pa((unsigned long)_text);
368         ro_end   = __pa((unsigned long)&data_start);
369         kernel_start = __pa((unsigned long)&__init_begin);
370         kernel_end  = __pa((unsigned long)&_end);
371
372         end_paddr = start_paddr + size;
373
374         /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */
375         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
376         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
377
378         address = start_paddr;
379         vaddr = start_vaddr;
380         while (address < end_paddr) {
381                 pgd_t *pgd = pgd_offset_k(vaddr);
382                 p4d_t *p4d = p4d_offset(pgd, vaddr);
383                 pud_t *pud = pud_offset(p4d, vaddr);
384
385 #if CONFIG_PGTABLE_LEVELS == 3
386                 if (pud_none(*pud)) {
387                         pmd = memblock_alloc(PAGE_SIZE << PMD_ORDER,
388                                              PAGE_SIZE << PMD_ORDER);
389                         if (!pmd)
390                                 panic("pmd allocation failed.\n");
391                         pud_populate(NULL, pud, pmd);
392                 }
393 #endif
394
395                 pmd = pmd_offset(pud, vaddr);
396                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
397                         if (pmd_none(*pmd)) {
398                                 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
399                                 if (!pg_table)
400                                         panic("page table allocation failed\n");
401                                 pmd_populate_kernel(NULL, pmd, pg_table);
402                         }
403
404                         pg_table = pte_offset_kernel(pmd, vaddr);
405                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
406                                 pte_t pte;
407                                 pgprot_t prot;
408                                 bool huge = false;
409
410                                 if (force) {
411                                         prot = pgprot;
412                                 } else if (address < kernel_start || address >= kernel_end) {
413                                         /* outside kernel memory */
414                                         prot = PAGE_KERNEL;
415                                 } else if (!kernel_set_to_readonly) {
416                                         /* still initializing, allow writing to RO memory */
417                                         prot = PAGE_KERNEL_RWX;
418                                         huge = true;
419                                 } else if (address >= ro_start) {
420                                         /* Code (ro) and Data areas */
421                                         prot = (address < ro_end) ?
422                                                 PAGE_KERNEL_EXEC : PAGE_KERNEL;
423                                         huge = true;
424                                 } else {
425                                         prot = PAGE_KERNEL;
426                                 }
427
428                                 pte = __mk_pte(address, prot);
429                                 if (huge)
430                                         pte = pte_mkhuge(pte);
431
432                                 if (address >= end_paddr)
433                                         break;
434
435                                 set_pte(pg_table, pte);
436
437                                 address += PAGE_SIZE;
438                                 vaddr += PAGE_SIZE;
439                         }
440                         start_pte = 0;
441
442                         if (address >= end_paddr)
443                             break;
444                 }
445                 start_pmd = 0;
446         }
447 }
448
449 void __init set_kernel_text_rw(int enable_read_write)
450 {
451         unsigned long start = (unsigned long) __init_begin;
452         unsigned long end   = (unsigned long) &data_start;
453
454         map_pages(start, __pa(start), end-start,
455                 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
456
457         /* force the kernel to see the new page table entries */
458         flush_cache_all();
459         flush_tlb_all();
460 }
461
462 void __ref free_initmem(void)
463 {
464         unsigned long init_begin = (unsigned long)__init_begin;
465         unsigned long init_end = (unsigned long)__init_end;
466         unsigned long kernel_end  = (unsigned long)&_end;
467
468         /* Remap kernel text and data, but do not touch init section yet. */
469         kernel_set_to_readonly = true;
470         map_pages(init_end, __pa(init_end), kernel_end - init_end,
471                   PAGE_KERNEL, 0);
472
473         /* The init text pages are marked R-X.  We have to
474          * flush the icache and mark them RW-
475          *
476          * This is tricky, because map_pages is in the init section.
477          * Do a dummy remap of the data section first (the data
478          * section is already PAGE_KERNEL) to pull in the TLB entries
479          * for map_kernel */
480         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
481                   PAGE_KERNEL_RWX, 1);
482         /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
483          * map_pages */
484         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
485                   PAGE_KERNEL, 1);
486
487         /* force the kernel to see the new TLB entries */
488         __flush_tlb_range(0, init_begin, kernel_end);
489
490         /* finally dump all the instructions which were cached, since the
491          * pages are no-longer executable */
492         flush_icache_range(init_begin, init_end);
493         
494         free_initmem_default(POISON_FREE_INITMEM);
495
496         /* set up a new led state on systems shipped LED State panel */
497         pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
498 }
499
500
501 #ifdef CONFIG_STRICT_KERNEL_RWX
502 void mark_rodata_ro(void)
503 {
504         /* rodata memory was already mapped with KERNEL_RO access rights by
505            pagetable_init() and map_pages(). No need to do additional stuff here */
506         unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
507
508         pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
509 }
510 #endif
511
512
513 /*
514  * Just an arbitrary offset to serve as a "hole" between mapping areas
515  * (between top of physical memory and a potential pcxl dma mapping
516  * area, and below the vmalloc mapping area).
517  *
518  * The current 32K value just means that there will be a 32K "hole"
519  * between mapping areas. That means that  any out-of-bounds memory
520  * accesses will hopefully be caught. The vmalloc() routines leaves
521  * a hole of 4kB between each vmalloced area for the same reason.
522  */
523
524  /* Leave room for gateway page expansion */
525 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
526 #error KERNEL_MAP_START is in gateway reserved region
527 #endif
528 #define MAP_START (KERNEL_MAP_START)
529
530 #define VM_MAP_OFFSET  (32*1024)
531 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
532                                      & ~(VM_MAP_OFFSET-1)))
533
534 void *parisc_vmalloc_start __ro_after_init;
535 EXPORT_SYMBOL(parisc_vmalloc_start);
536
537 #ifdef CONFIG_PA11
538 unsigned long pcxl_dma_start __ro_after_init;
539 #endif
540
541 void __init mem_init(void)
542 {
543         /* Do sanity checks on IPC (compat) structures */
544         BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
545 #ifndef CONFIG_64BIT
546         BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
547         BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
548         BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
549 #endif
550 #ifdef CONFIG_COMPAT
551         BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
552         BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
553         BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
554         BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
555 #endif
556
557         /* Do sanity checks on page table constants */
558         BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
559         BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
560         BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
561         BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
562                         > BITS_PER_LONG);
563
564         high_memory = __va((max_pfn << PAGE_SHIFT));
565         set_max_mapnr(page_to_pfn(virt_to_page(high_memory - 1)) + 1);
566         memblock_free_all();
567
568 #ifdef CONFIG_PA11
569         if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
570                 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
571                 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
572                                                 + PCXL_DMA_MAP_SIZE);
573         } else
574 #endif
575                 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
576
577         mem_init_print_info(NULL);
578
579 #if 0
580         /*
581          * Do not expose the virtual kernel memory layout to userspace.
582          * But keep code for debugging purposes.
583          */
584         printk("virtual kernel memory layout:\n"
585                "     vmalloc : 0x%px - 0x%px   (%4ld MB)\n"
586                "     fixmap  : 0x%px - 0x%px   (%4ld kB)\n"
587                "     memory  : 0x%px - 0x%px   (%4ld MB)\n"
588                "       .init : 0x%px - 0x%px   (%4ld kB)\n"
589                "       .data : 0x%px - 0x%px   (%4ld kB)\n"
590                "       .text : 0x%px - 0x%px   (%4ld kB)\n",
591
592                (void*)VMALLOC_START, (void*)VMALLOC_END,
593                (VMALLOC_END - VMALLOC_START) >> 20,
594
595                (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
596                (unsigned long)(FIXMAP_SIZE / 1024),
597
598                __va(0), high_memory,
599                ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
600
601                __init_begin, __init_end,
602                ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
603
604                _etext, _edata,
605                ((unsigned long)_edata - (unsigned long)_etext) >> 10,
606
607                _text, _etext,
608                ((unsigned long)_etext - (unsigned long)_text) >> 10);
609 #endif
610 }
611
612 unsigned long *empty_zero_page __ro_after_init;
613 EXPORT_SYMBOL(empty_zero_page);
614
615 /*
616  * pagetable_init() sets up the page tables
617  *
618  * Note that gateway_init() places the Linux gateway page at page 0.
619  * Since gateway pages cannot be dereferenced this has the desirable
620  * side effect of trapping those pesky NULL-reference errors in the
621  * kernel.
622  */
623 static void __init pagetable_init(void)
624 {
625         int range;
626
627         /* Map each physical memory range to its kernel vaddr */
628
629         for (range = 0; range < npmem_ranges; range++) {
630                 unsigned long start_paddr;
631                 unsigned long end_paddr;
632                 unsigned long size;
633
634                 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
635                 size = pmem_ranges[range].pages << PAGE_SHIFT;
636                 end_paddr = start_paddr + size;
637
638                 map_pages((unsigned long)__va(start_paddr), start_paddr,
639                           size, PAGE_KERNEL, 0);
640         }
641
642 #ifdef CONFIG_BLK_DEV_INITRD
643         if (initrd_end && initrd_end > mem_limit) {
644                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
645                 map_pages(initrd_start, __pa(initrd_start),
646                           initrd_end - initrd_start, PAGE_KERNEL, 0);
647         }
648 #endif
649
650         empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
651         if (!empty_zero_page)
652                 panic("zero page allocation failed.\n");
653
654 }
655
656 static void __init gateway_init(void)
657 {
658         unsigned long linux_gateway_page_addr;
659         /* FIXME: This is 'const' in order to trick the compiler
660            into not treating it as DP-relative data. */
661         extern void * const linux_gateway_page;
662
663         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
664
665         /*
666          * Setup Linux Gateway page.
667          *
668          * The Linux gateway page will reside in kernel space (on virtual
669          * page 0), so it doesn't need to be aliased into user space.
670          */
671
672         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
673                   PAGE_SIZE, PAGE_GATEWAY, 1);
674 }
675
676 static void __init parisc_bootmem_free(void)
677 {
678         unsigned long zones_size[MAX_NR_ZONES] = { 0, };
679         unsigned long holes_size[MAX_NR_ZONES] = { 0, };
680         unsigned long mem_start_pfn = ~0UL, mem_end_pfn = 0, mem_size_pfn = 0;
681         int i;
682
683         for (i = 0; i < npmem_ranges; i++) {
684                 unsigned long start = pmem_ranges[i].start_pfn;
685                 unsigned long size = pmem_ranges[i].pages;
686                 unsigned long end = start + size;
687
688                 if (mem_start_pfn > start)
689                         mem_start_pfn = start;
690                 if (mem_end_pfn < end)
691                         mem_end_pfn = end;
692                 mem_size_pfn += size;
693         }
694
695         zones_size[0] = mem_end_pfn - mem_start_pfn;
696         holes_size[0] = zones_size[0] - mem_size_pfn;
697
698         free_area_init_node(0, zones_size, mem_start_pfn, holes_size);
699 }
700
701 void __init paging_init(void)
702 {
703         setup_bootmem();
704         pagetable_init();
705         gateway_init();
706         flush_cache_all_local(); /* start with known state */
707         flush_tlb_all_local(NULL);
708
709         /*
710          * Mark all memblocks as present for sparsemem using
711          * memory_present() and then initialize sparsemem.
712          */
713         memblocks_present();
714         sparse_init();
715         parisc_bootmem_free();
716 }
717
718 #ifdef CONFIG_PA20
719
720 /*
721  * Currently, all PA20 chips have 18 bit protection IDs, which is the
722  * limiting factor (space ids are 32 bits).
723  */
724
725 #define NR_SPACE_IDS 262144
726
727 #else
728
729 /*
730  * Currently we have a one-to-one relationship between space IDs and
731  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
732  * support 15 bit protection IDs, so that is the limiting factor.
733  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
734  * probably not worth the effort for a special case here.
735  */
736
737 #define NR_SPACE_IDS 32768
738
739 #endif  /* !CONFIG_PA20 */
740
741 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
742 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
743
744 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
745 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
746 static unsigned long space_id_index;
747 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
748 static unsigned long dirty_space_ids = 0;
749
750 static DEFINE_SPINLOCK(sid_lock);
751
752 unsigned long alloc_sid(void)
753 {
754         unsigned long index;
755
756         spin_lock(&sid_lock);
757
758         if (free_space_ids == 0) {
759                 if (dirty_space_ids != 0) {
760                         spin_unlock(&sid_lock);
761                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
762                         spin_lock(&sid_lock);
763                 }
764                 BUG_ON(free_space_ids == 0);
765         }
766
767         free_space_ids--;
768
769         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
770         space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
771         space_id_index = index;
772
773         spin_unlock(&sid_lock);
774
775         return index << SPACEID_SHIFT;
776 }
777
778 void free_sid(unsigned long spaceid)
779 {
780         unsigned long index = spaceid >> SPACEID_SHIFT;
781         unsigned long *dirty_space_offset;
782
783         dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
784         index &= (BITS_PER_LONG - 1);
785
786         spin_lock(&sid_lock);
787
788         BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
789
790         *dirty_space_offset |= (1L << index);
791         dirty_space_ids++;
792
793         spin_unlock(&sid_lock);
794 }
795
796
797 #ifdef CONFIG_SMP
798 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
799 {
800         int i;
801
802         /* NOTE: sid_lock must be held upon entry */
803
804         *ndirtyptr = dirty_space_ids;
805         if (dirty_space_ids != 0) {
806             for (i = 0; i < SID_ARRAY_SIZE; i++) {
807                 dirty_array[i] = dirty_space_id[i];
808                 dirty_space_id[i] = 0;
809             }
810             dirty_space_ids = 0;
811         }
812
813         return;
814 }
815
816 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
817 {
818         int i;
819
820         /* NOTE: sid_lock must be held upon entry */
821
822         if (ndirty != 0) {
823                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
824                         space_id[i] ^= dirty_array[i];
825                 }
826
827                 free_space_ids += ndirty;
828                 space_id_index = 0;
829         }
830 }
831
832 #else /* CONFIG_SMP */
833
834 static void recycle_sids(void)
835 {
836         int i;
837
838         /* NOTE: sid_lock must be held upon entry */
839
840         if (dirty_space_ids != 0) {
841                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
842                         space_id[i] ^= dirty_space_id[i];
843                         dirty_space_id[i] = 0;
844                 }
845
846                 free_space_ids += dirty_space_ids;
847                 dirty_space_ids = 0;
848                 space_id_index = 0;
849         }
850 }
851 #endif
852
853 /*
854  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
855  * purged, we can safely reuse the space ids that were released but
856  * not flushed from the tlb.
857  */
858
859 #ifdef CONFIG_SMP
860
861 static unsigned long recycle_ndirty;
862 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
863 static unsigned int recycle_inuse;
864
865 void flush_tlb_all(void)
866 {
867         int do_recycle;
868
869         __inc_irq_stat(irq_tlb_count);
870         do_recycle = 0;
871         spin_lock(&sid_lock);
872         if (dirty_space_ids > RECYCLE_THRESHOLD) {
873             BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
874             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
875             recycle_inuse++;
876             do_recycle++;
877         }
878         spin_unlock(&sid_lock);
879         on_each_cpu(flush_tlb_all_local, NULL, 1);
880         if (do_recycle) {
881             spin_lock(&sid_lock);
882             recycle_sids(recycle_ndirty,recycle_dirty_array);
883             recycle_inuse = 0;
884             spin_unlock(&sid_lock);
885         }
886 }
887 #else
888 void flush_tlb_all(void)
889 {
890         __inc_irq_stat(irq_tlb_count);
891         spin_lock(&sid_lock);
892         flush_tlb_all_local(NULL);
893         recycle_sids();
894         spin_unlock(&sid_lock);
895 }
896 #endif