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/tlb.h>
30 #include <asm/pdc_chassis.h>
31 #include <asm/mmzone.h>
32 #include <asm/sections.h>
33 #include <asm/msgbuf.h>
34 #include <asm/sparsemem.h>
35
36 extern int data_start;
37 extern void parisc_kernel_start(void); /* Kernel entry point in head.S */
38
39 #if CONFIG_PGTABLE_LEVELS == 3
40 pmd_t pmd0[PTRS_PER_PMD] __section(".data..vm0.pmd") __attribute__ ((aligned(PAGE_SIZE)));
41 #endif
42
43 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".data..vm0.pgd") __attribute__ ((aligned(PAGE_SIZE)));
44 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __section(".data..vm0.pte") __attribute__ ((aligned(PAGE_SIZE)));
45
46 static struct resource data_resource = {
47 .name = "Kernel data",
48 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
49 };
50
51 static struct resource code_resource = {
52 .name = "Kernel code",
53 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
54 };
55
56 static struct resource pdcdata_resource = {
57 .name = "PDC data (Page Zero)",
58 .start = 0,
59 .end = 0x9ff,
60 .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
61 };
62
63 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init;
64
65 /* The following array is initialized from the firmware specific
66 * information retrieved in kernel/inventory.c.
67 */
68
69 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata;
70 int npmem_ranges __initdata;
71
72 #ifdef CONFIG_64BIT
73 #define MAX_MEM (1UL << MAX_PHYSMEM_BITS)
74 #else /* !CONFIG_64BIT */
75 #define MAX_MEM (3584U*1024U*1024U)
76 #endif /* !CONFIG_64BIT */
77
78 static unsigned long mem_limit __read_mostly = MAX_MEM;
79
mem_limit_func(void)80 static void __init mem_limit_func(void)
81 {
82 char *cp, *end;
83 unsigned long limit;
84
85 /* We need this before __setup() functions are called */
86
87 limit = MAX_MEM;
88 for (cp = boot_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
setup_bootmem(void)109 static void __init setup_bootmem(void)
110 {
111 unsigned long mem_max;
112 #ifndef CONFIG_SPARSEMEM
113 physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
114 int npmem_holes;
115 #endif
116 int i, sysram_resource_count;
117
118 disable_sr_hashing(); /* Turn off space register hashing */
119
120 /*
121 * Sort the ranges. Since the number of ranges is typically
122 * small, and performance is not an issue here, just do
123 * a simple insertion sort.
124 */
125
126 for (i = 1; i < npmem_ranges; i++) {
127 int j;
128
129 for (j = i; j > 0; j--) {
130 if (pmem_ranges[j-1].start_pfn <
131 pmem_ranges[j].start_pfn) {
132
133 break;
134 }
135 swap(pmem_ranges[j-1], pmem_ranges[j]);
136 }
137 }
138
139 #ifndef CONFIG_SPARSEMEM
140 /*
141 * Throw out ranges that are too far apart (controlled by
142 * MAX_GAP).
143 */
144
145 for (i = 1; i < npmem_ranges; i++) {
146 if (pmem_ranges[i].start_pfn -
147 (pmem_ranges[i-1].start_pfn +
148 pmem_ranges[i-1].pages) > MAX_GAP) {
149 npmem_ranges = i;
150 printk("Large gap in memory detected (%ld pages). "
151 "Consider turning on CONFIG_SPARSEMEM\n",
152 pmem_ranges[i].start_pfn -
153 (pmem_ranges[i-1].start_pfn +
154 pmem_ranges[i-1].pages));
155 break;
156 }
157 }
158 #endif
159
160 /* Print the memory ranges */
161 pr_info("Memory Ranges:\n");
162
163 for (i = 0; i < npmem_ranges; i++) {
164 struct resource *res = &sysram_resources[i];
165 unsigned long start;
166 unsigned long size;
167
168 size = (pmem_ranges[i].pages << PAGE_SHIFT);
169 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
170 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
171 i, start, start + (size - 1), size >> 20);
172
173 /* request memory resource */
174 res->name = "System RAM";
175 res->start = start;
176 res->end = start + size - 1;
177 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
178 request_resource(&iomem_resource, res);
179 }
180
181 sysram_resource_count = npmem_ranges;
182
183 /*
184 * For 32 bit kernels we limit the amount of memory we can
185 * support, in order to preserve enough kernel address space
186 * for other purposes. For 64 bit kernels we don't normally
187 * limit the memory, but this mechanism can be used to
188 * artificially limit the amount of memory (and it is written
189 * to work with multiple memory ranges).
190 */
191
192 mem_limit_func(); /* check for "mem=" argument */
193
194 mem_max = 0;
195 for (i = 0; i < npmem_ranges; i++) {
196 unsigned long rsize;
197
198 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
199 if ((mem_max + rsize) > mem_limit) {
200 printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
201 if (mem_max == mem_limit)
202 npmem_ranges = i;
203 else {
204 pmem_ranges[i].pages = (mem_limit >> PAGE_SHIFT)
205 - (mem_max >> PAGE_SHIFT);
206 npmem_ranges = i + 1;
207 mem_max = mem_limit;
208 }
209 break;
210 }
211 mem_max += rsize;
212 }
213
214 printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
215
216 #ifndef CONFIG_SPARSEMEM
217 /* Merge the ranges, keeping track of the holes */
218 {
219 unsigned long end_pfn;
220 unsigned long hole_pages;
221
222 npmem_holes = 0;
223 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
224 for (i = 1; i < npmem_ranges; i++) {
225
226 hole_pages = pmem_ranges[i].start_pfn - end_pfn;
227 if (hole_pages) {
228 pmem_holes[npmem_holes].start_pfn = end_pfn;
229 pmem_holes[npmem_holes++].pages = hole_pages;
230 end_pfn += hole_pages;
231 }
232 end_pfn += pmem_ranges[i].pages;
233 }
234
235 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
236 npmem_ranges = 1;
237 }
238 #endif
239
240 /*
241 * Initialize and free the full range of memory in each range.
242 */
243
244 max_pfn = 0;
245 for (i = 0; i < npmem_ranges; i++) {
246 unsigned long start_pfn;
247 unsigned long npages;
248 unsigned long start;
249 unsigned long size;
250
251 start_pfn = pmem_ranges[i].start_pfn;
252 npages = pmem_ranges[i].pages;
253
254 start = start_pfn << PAGE_SHIFT;
255 size = npages << PAGE_SHIFT;
256
257 /* add system RAM memblock */
258 memblock_add(start, size);
259
260 if ((start_pfn + npages) > max_pfn)
261 max_pfn = start_pfn + npages;
262 }
263
264 /*
265 * We can't use memblock top-down allocations because we only
266 * created the initial mapping up to KERNEL_INITIAL_SIZE in
267 * the assembly bootup code.
268 */
269 memblock_set_bottom_up(true);
270
271 /* IOMMU is always used to access "high mem" on those boxes
272 * that can support enough mem that a PCI device couldn't
273 * directly DMA to any physical addresses.
274 * ISA DMA support will need to revisit this.
275 */
276 max_low_pfn = max_pfn;
277
278 /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
279
280 #define PDC_CONSOLE_IO_IODC_SIZE 32768
281
282 memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
283 PDC_CONSOLE_IO_IODC_SIZE));
284 memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
285 (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
286
287 #ifndef CONFIG_SPARSEMEM
288
289 /* reserve the holes */
290
291 for (i = 0; i < npmem_holes; i++) {
292 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
293 (pmem_holes[i].pages << PAGE_SHIFT));
294 }
295 #endif
296
297 #ifdef CONFIG_BLK_DEV_INITRD
298 if (initrd_start) {
299 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
300 if (__pa(initrd_start) < mem_max) {
301 unsigned long initrd_reserve;
302
303 if (__pa(initrd_end) > mem_max) {
304 initrd_reserve = mem_max - __pa(initrd_start);
305 } else {
306 initrd_reserve = initrd_end - initrd_start;
307 }
308 initrd_below_start_ok = 1;
309 printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
310
311 memblock_reserve(__pa(initrd_start), initrd_reserve);
312 }
313 }
314 #endif
315
316 data_resource.start = virt_to_phys(&data_start);
317 data_resource.end = virt_to_phys(_end) - 1;
318 code_resource.start = virt_to_phys(_text);
319 code_resource.end = virt_to_phys(&data_start)-1;
320
321 /* We don't know which region the kernel will be in, so try
322 * all of them.
323 */
324 for (i = 0; i < sysram_resource_count; i++) {
325 struct resource *res = &sysram_resources[i];
326 request_resource(res, &code_resource);
327 request_resource(res, &data_resource);
328 }
329 request_resource(&sysram_resources[0], &pdcdata_resource);
330
331 /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
332 pdc_pdt_init();
333
334 memblock_allow_resize();
335 memblock_dump_all();
336 }
337
338 static bool kernel_set_to_readonly;
339
map_pages(unsigned long start_vaddr,unsigned long start_paddr,unsigned long size,pgprot_t pgprot,int force)340 static void __ref map_pages(unsigned long start_vaddr,
341 unsigned long start_paddr, unsigned long size,
342 pgprot_t pgprot, int force)
343 {
344 pmd_t *pmd;
345 pte_t *pg_table;
346 unsigned long end_paddr;
347 unsigned long start_pmd;
348 unsigned long start_pte;
349 unsigned long tmp1;
350 unsigned long tmp2;
351 unsigned long address;
352 unsigned long vaddr;
353 unsigned long ro_start;
354 unsigned long ro_end;
355 unsigned long kernel_start, kernel_end;
356
357 ro_start = __pa((unsigned long)_text);
358 ro_end = __pa((unsigned long)&data_start);
359 kernel_start = __pa((unsigned long)&__init_begin);
360 kernel_end = __pa((unsigned long)&_end);
361
362 end_paddr = start_paddr + size;
363
364 /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */
365 start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
366 start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
367
368 address = start_paddr;
369 vaddr = start_vaddr;
370 while (address < end_paddr) {
371 pgd_t *pgd = pgd_offset_k(vaddr);
372 p4d_t *p4d = p4d_offset(pgd, vaddr);
373 pud_t *pud = pud_offset(p4d, vaddr);
374
375 #if CONFIG_PGTABLE_LEVELS == 3
376 if (pud_none(*pud)) {
377 pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER,
378 PAGE_SIZE << PMD_TABLE_ORDER);
379 if (!pmd)
380 panic("pmd allocation failed.\n");
381 pud_populate(NULL, pud, pmd);
382 }
383 #endif
384
385 pmd = pmd_offset(pud, vaddr);
386 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
387 if (pmd_none(*pmd)) {
388 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
389 if (!pg_table)
390 panic("page table allocation failed\n");
391 pmd_populate_kernel(NULL, pmd, pg_table);
392 }
393
394 pg_table = pte_offset_kernel(pmd, vaddr);
395 for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
396 pte_t pte;
397 pgprot_t prot;
398 bool huge = false;
399
400 if (force) {
401 prot = pgprot;
402 } else if (address < kernel_start || address >= kernel_end) {
403 /* outside kernel memory */
404 prot = PAGE_KERNEL;
405 } else if (!kernel_set_to_readonly) {
406 /* still initializing, allow writing to RO memory */
407 prot = PAGE_KERNEL_RWX;
408 huge = true;
409 } else if (address >= ro_start) {
410 /* Code (ro) and Data areas */
411 prot = (address < ro_end) ?
412 PAGE_KERNEL_EXEC : PAGE_KERNEL;
413 huge = true;
414 } else {
415 prot = PAGE_KERNEL;
416 }
417
418 pte = __mk_pte(address, prot);
419 if (huge)
420 pte = pte_mkhuge(pte);
421
422 if (address >= end_paddr)
423 break;
424
425 set_pte(pg_table, pte);
426
427 address += PAGE_SIZE;
428 vaddr += PAGE_SIZE;
429 }
430 start_pte = 0;
431
432 if (address >= end_paddr)
433 break;
434 }
435 start_pmd = 0;
436 }
437 }
438
set_kernel_text_rw(int enable_read_write)439 void __init set_kernel_text_rw(int enable_read_write)
440 {
441 unsigned long start = (unsigned long) __init_begin;
442 unsigned long end = (unsigned long) &data_start;
443
444 map_pages(start, __pa(start), end-start,
445 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
446
447 /* force the kernel to see the new page table entries */
448 flush_cache_all();
449 flush_tlb_all();
450 }
451
free_initmem(void)452 void free_initmem(void)
453 {
454 unsigned long init_begin = (unsigned long)__init_begin;
455 unsigned long init_end = (unsigned long)__init_end;
456 unsigned long kernel_end = (unsigned long)&_end;
457
458 /* Remap kernel text and data, but do not touch init section yet. */
459 kernel_set_to_readonly = true;
460 map_pages(init_end, __pa(init_end), kernel_end - init_end,
461 PAGE_KERNEL, 0);
462
463 /* The init text pages are marked R-X. We have to
464 * flush the icache and mark them RW-
465 *
466 * Do a dummy remap of the data section first (the data
467 * section is already PAGE_KERNEL) to pull in the TLB entries
468 * for map_kernel */
469 map_pages(init_begin, __pa(init_begin), init_end - init_begin,
470 PAGE_KERNEL_RWX, 1);
471 /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
472 * map_pages */
473 map_pages(init_begin, __pa(init_begin), init_end - init_begin,
474 PAGE_KERNEL, 1);
475
476 /* force the kernel to see the new TLB entries */
477 __flush_tlb_range(0, init_begin, kernel_end);
478
479 /* finally dump all the instructions which were cached, since the
480 * pages are no-longer executable */
481 flush_icache_range(init_begin, init_end);
482
483 free_initmem_default(POISON_FREE_INITMEM);
484
485 /* set up a new led state on systems shipped LED State panel */
486 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
487 }
488
489
490 #ifdef CONFIG_STRICT_KERNEL_RWX
mark_rodata_ro(void)491 void mark_rodata_ro(void)
492 {
493 /* rodata memory was already mapped with KERNEL_RO access rights by
494 pagetable_init() and map_pages(). No need to do additional stuff here */
495 unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
496
497 pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
498 }
499 #endif
500
501
502 /*
503 * Just an arbitrary offset to serve as a "hole" between mapping areas
504 * (between top of physical memory and a potential pcxl dma mapping
505 * area, and below the vmalloc mapping area).
506 *
507 * The current 32K value just means that there will be a 32K "hole"
508 * between mapping areas. That means that any out-of-bounds memory
509 * accesses will hopefully be caught. The vmalloc() routines leaves
510 * a hole of 4kB between each vmalloced area for the same reason.
511 */
512
513 /* Leave room for gateway page expansion */
514 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
515 #error KERNEL_MAP_START is in gateway reserved region
516 #endif
517 #define MAP_START (KERNEL_MAP_START)
518
519 #define VM_MAP_OFFSET (32*1024)
520 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
521 & ~(VM_MAP_OFFSET-1)))
522
523 void *parisc_vmalloc_start __ro_after_init;
524 EXPORT_SYMBOL(parisc_vmalloc_start);
525
526 #ifdef CONFIG_PA11
527 unsigned long pcxl_dma_start __ro_after_init;
528 #endif
529
mem_init(void)530 void __init mem_init(void)
531 {
532 /* Do sanity checks on IPC (compat) structures */
533 BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
534 #ifndef CONFIG_64BIT
535 BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
536 BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
537 BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
538 #endif
539 #ifdef CONFIG_COMPAT
540 BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
541 BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
542 BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
543 BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
544 #endif
545
546 /* Do sanity checks on page table constants */
547 BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
548 BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
549 BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
550 BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
551 > BITS_PER_LONG);
552 #if CONFIG_PGTABLE_LEVELS == 3
553 BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PMD);
554 #else
555 BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PGD);
556 #endif
557
558 #ifdef CONFIG_64BIT
559 /* avoid ldil_%L() asm statements to sign-extend into upper 32-bits */
560 BUILD_BUG_ON(__PAGE_OFFSET >= 0x80000000);
561 BUILD_BUG_ON(TMPALIAS_MAP_START >= 0x80000000);
562 #endif
563
564 high_memory = __va((max_pfn << PAGE_SHIFT));
565 set_max_mapnr(max_low_pfn);
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 #if 0
578 /*
579 * Do not expose the virtual kernel memory layout to userspace.
580 * But keep code for debugging purposes.
581 */
582 printk("virtual kernel memory layout:\n"
583 " vmalloc : 0x%px - 0x%px (%4ld MB)\n"
584 " fixmap : 0x%px - 0x%px (%4ld kB)\n"
585 " memory : 0x%px - 0x%px (%4ld MB)\n"
586 " .init : 0x%px - 0x%px (%4ld kB)\n"
587 " .data : 0x%px - 0x%px (%4ld kB)\n"
588 " .text : 0x%px - 0x%px (%4ld kB)\n",
589
590 (void*)VMALLOC_START, (void*)VMALLOC_END,
591 (VMALLOC_END - VMALLOC_START) >> 20,
592
593 (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
594 (unsigned long)(FIXMAP_SIZE / 1024),
595
596 __va(0), high_memory,
597 ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
598
599 __init_begin, __init_end,
600 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
601
602 _etext, _edata,
603 ((unsigned long)_edata - (unsigned long)_etext) >> 10,
604
605 _text, _etext,
606 ((unsigned long)_etext - (unsigned long)_text) >> 10);
607 #endif
608 }
609
610 unsigned long *empty_zero_page __ro_after_init;
611 EXPORT_SYMBOL(empty_zero_page);
612
613 /*
614 * pagetable_init() sets up the page tables
615 *
616 * Note that gateway_init() places the Linux gateway page at page 0.
617 * Since gateway pages cannot be dereferenced this has the desirable
618 * side effect of trapping those pesky NULL-reference errors in the
619 * kernel.
620 */
pagetable_init(void)621 static void __init pagetable_init(void)
622 {
623 int range;
624
625 /* Map each physical memory range to its kernel vaddr */
626
627 for (range = 0; range < npmem_ranges; range++) {
628 unsigned long start_paddr;
629 unsigned long end_paddr;
630 unsigned long size;
631
632 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
633 size = pmem_ranges[range].pages << PAGE_SHIFT;
634 end_paddr = start_paddr + size;
635
636 map_pages((unsigned long)__va(start_paddr), start_paddr,
637 size, PAGE_KERNEL, 0);
638 }
639
640 #ifdef CONFIG_BLK_DEV_INITRD
641 if (initrd_end && initrd_end > mem_limit) {
642 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
643 map_pages(initrd_start, __pa(initrd_start),
644 initrd_end - initrd_start, PAGE_KERNEL, 0);
645 }
646 #endif
647
648 empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
649 if (!empty_zero_page)
650 panic("zero page allocation failed.\n");
651
652 }
653
gateway_init(void)654 static void __init gateway_init(void)
655 {
656 unsigned long linux_gateway_page_addr;
657 /* FIXME: This is 'const' in order to trick the compiler
658 into not treating it as DP-relative data. */
659 extern void * const linux_gateway_page;
660
661 linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
662
663 /*
664 * Setup Linux Gateway page.
665 *
666 * The Linux gateway page will reside in kernel space (on virtual
667 * page 0), so it doesn't need to be aliased into user space.
668 */
669
670 map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
671 PAGE_SIZE, PAGE_GATEWAY, 1);
672 }
673
parisc_bootmem_free(void)674 static void __init parisc_bootmem_free(void)
675 {
676 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
677
678 max_zone_pfn[0] = memblock_end_of_DRAM();
679
680 free_area_init(max_zone_pfn);
681 }
682
paging_init(void)683 void __init paging_init(void)
684 {
685 setup_bootmem();
686 pagetable_init();
687 gateway_init();
688 flush_cache_all_local(); /* start with known state */
689 flush_tlb_all_local(NULL);
690
691 sparse_init();
692 parisc_bootmem_free();
693 }
694
695 #ifdef CONFIG_PA20
696
697 /*
698 * Currently, all PA20 chips have 18 bit protection IDs, which is the
699 * limiting factor (space ids are 32 bits).
700 */
701
702 #define NR_SPACE_IDS 262144
703
704 #else
705
706 /*
707 * Currently we have a one-to-one relationship between space IDs and
708 * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
709 * support 15 bit protection IDs, so that is the limiting factor.
710 * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
711 * probably not worth the effort for a special case here.
712 */
713
714 #define NR_SPACE_IDS 32768
715
716 #endif /* !CONFIG_PA20 */
717
718 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
719 #define SID_ARRAY_SIZE (NR_SPACE_IDS / (8 * sizeof(long)))
720
721 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
722 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
723 static unsigned long space_id_index;
724 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
725 static unsigned long dirty_space_ids;
726
727 static DEFINE_SPINLOCK(sid_lock);
728
alloc_sid(void)729 unsigned long alloc_sid(void)
730 {
731 unsigned long index;
732
733 spin_lock(&sid_lock);
734
735 if (free_space_ids == 0) {
736 if (dirty_space_ids != 0) {
737 spin_unlock(&sid_lock);
738 flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
739 spin_lock(&sid_lock);
740 }
741 BUG_ON(free_space_ids == 0);
742 }
743
744 free_space_ids--;
745
746 index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
747 space_id[BIT_WORD(index)] |= BIT_MASK(index);
748 space_id_index = index;
749
750 spin_unlock(&sid_lock);
751
752 return index << SPACEID_SHIFT;
753 }
754
free_sid(unsigned long spaceid)755 void free_sid(unsigned long spaceid)
756 {
757 unsigned long index = spaceid >> SPACEID_SHIFT;
758 unsigned long *dirty_space_offset, mask;
759
760 dirty_space_offset = &dirty_space_id[BIT_WORD(index)];
761 mask = BIT_MASK(index);
762
763 spin_lock(&sid_lock);
764
765 BUG_ON(*dirty_space_offset & mask); /* attempt to free space id twice */
766
767 *dirty_space_offset |= mask;
768 dirty_space_ids++;
769
770 spin_unlock(&sid_lock);
771 }
772
773
774 #ifdef CONFIG_SMP
get_dirty_sids(unsigned long * ndirtyptr,unsigned long * dirty_array)775 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
776 {
777 int i;
778
779 /* NOTE: sid_lock must be held upon entry */
780
781 *ndirtyptr = dirty_space_ids;
782 if (dirty_space_ids != 0) {
783 for (i = 0; i < SID_ARRAY_SIZE; i++) {
784 dirty_array[i] = dirty_space_id[i];
785 dirty_space_id[i] = 0;
786 }
787 dirty_space_ids = 0;
788 }
789
790 return;
791 }
792
recycle_sids(unsigned long ndirty,unsigned long * dirty_array)793 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
794 {
795 int i;
796
797 /* NOTE: sid_lock must be held upon entry */
798
799 if (ndirty != 0) {
800 for (i = 0; i < SID_ARRAY_SIZE; i++) {
801 space_id[i] ^= dirty_array[i];
802 }
803
804 free_space_ids += ndirty;
805 space_id_index = 0;
806 }
807 }
808
809 #else /* CONFIG_SMP */
810
recycle_sids(void)811 static void recycle_sids(void)
812 {
813 int i;
814
815 /* NOTE: sid_lock must be held upon entry */
816
817 if (dirty_space_ids != 0) {
818 for (i = 0; i < SID_ARRAY_SIZE; i++) {
819 space_id[i] ^= dirty_space_id[i];
820 dirty_space_id[i] = 0;
821 }
822
823 free_space_ids += dirty_space_ids;
824 dirty_space_ids = 0;
825 space_id_index = 0;
826 }
827 }
828 #endif
829
830 /*
831 * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
832 * purged, we can safely reuse the space ids that were released but
833 * not flushed from the tlb.
834 */
835
836 #ifdef CONFIG_SMP
837
838 static unsigned long recycle_ndirty;
839 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
840 static unsigned int recycle_inuse;
841
flush_tlb_all(void)842 void flush_tlb_all(void)
843 {
844 int do_recycle;
845
846 do_recycle = 0;
847 spin_lock(&sid_lock);
848 __inc_irq_stat(irq_tlb_count);
849 if (dirty_space_ids > RECYCLE_THRESHOLD) {
850 BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */
851 get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
852 recycle_inuse++;
853 do_recycle++;
854 }
855 spin_unlock(&sid_lock);
856 on_each_cpu(flush_tlb_all_local, NULL, 1);
857 if (do_recycle) {
858 spin_lock(&sid_lock);
859 recycle_sids(recycle_ndirty,recycle_dirty_array);
860 recycle_inuse = 0;
861 spin_unlock(&sid_lock);
862 }
863 }
864 #else
flush_tlb_all(void)865 void flush_tlb_all(void)
866 {
867 spin_lock(&sid_lock);
868 __inc_irq_stat(irq_tlb_count);
869 flush_tlb_all_local(NULL);
870 recycle_sids();
871 spin_unlock(&sid_lock);
872 }
873 #endif
874
875 static const pgprot_t protection_map[16] = {
876 [VM_NONE] = PAGE_NONE,
877 [VM_READ] = PAGE_READONLY,
878 [VM_WRITE] = PAGE_NONE,
879 [VM_WRITE | VM_READ] = PAGE_READONLY,
880 [VM_EXEC] = PAGE_EXECREAD,
881 [VM_EXEC | VM_READ] = PAGE_EXECREAD,
882 [VM_EXEC | VM_WRITE] = PAGE_EXECREAD,
883 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_EXECREAD,
884 [VM_SHARED] = PAGE_NONE,
885 [VM_SHARED | VM_READ] = PAGE_READONLY,
886 [VM_SHARED | VM_WRITE] = PAGE_WRITEONLY,
887 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
888 [VM_SHARED | VM_EXEC] = PAGE_EXECREAD,
889 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_EXECREAD,
890 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_RWX,
891 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_RWX
892 };
893 DECLARE_VM_GET_PAGE_PROT
894