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1/*
2 * linux/arch/arm/mm/init.c
3 *
4 * Copyright (C) 1995-2005 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#include <linux/kernel.h>
11#include <linux/errno.h>
12#include <linux/swap.h>
13#include <linux/init.h>
14#include <linux/bootmem.h>
15#include <linux/mman.h>
16#include <linux/nodemask.h>
17#include <linux/initrd.h>
18#include <linux/of_fdt.h>
19#include <linux/highmem.h>
20#include <linux/gfp.h>
21#include <linux/memblock.h>
22#include <linux/sort.h>
23
24#include <asm/mach-types.h>
25#include <asm/prom.h>
26#include <asm/sections.h>
27#include <asm/setup.h>
28#include <asm/sizes.h>
29#include <asm/tlb.h>
30#include <asm/fixmap.h>
31
32#include <asm/mach/arch.h>
33#include <asm/mach/map.h>
34
35#include "mm.h"
36
37static unsigned long phys_initrd_start __initdata = 0;
38static unsigned long phys_initrd_size __initdata = 0;
39
40static int __init early_initrd(char *p)
41{
42 unsigned long start, size;
43 char *endp;
44
45 start = memparse(p, &endp);
46 if (*endp == ',') {
47 size = memparse(endp + 1, NULL);
48
49 phys_initrd_start = start;
50 phys_initrd_size = size;
51 }
52 return 0;
53}
54early_param("initrd", early_initrd);
55
56static int __init parse_tag_initrd(const struct tag *tag)
57{
58 printk(KERN_WARNING "ATAG_INITRD is deprecated; "
59 "please update your bootloader.\n");
60 phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
61 phys_initrd_size = tag->u.initrd.size;
62 return 0;
63}
64
65__tagtable(ATAG_INITRD, parse_tag_initrd);
66
67static int __init parse_tag_initrd2(const struct tag *tag)
68{
69 phys_initrd_start = tag->u.initrd.start;
70 phys_initrd_size = tag->u.initrd.size;
71 return 0;
72}
73
74__tagtable(ATAG_INITRD2, parse_tag_initrd2);
75
76#ifdef CONFIG_OF_FLATTREE
77void __init early_init_dt_setup_initrd_arch(unsigned long start, unsigned long end)
78{
79 phys_initrd_start = start;
80 phys_initrd_size = end - start;
81}
82#endif /* CONFIG_OF_FLATTREE */
83
84/*
85 * This keeps memory configuration data used by a couple memory
86 * initialization functions, as well as show_mem() for the skipping
87 * of holes in the memory map. It is populated by arm_add_memory().
88 */
89struct meminfo meminfo;
90
91void show_mem(unsigned int filter)
92{
93 int free = 0, total = 0, reserved = 0;
94 int shared = 0, cached = 0, slab = 0, i;
95 struct meminfo * mi = &meminfo;
96
97 printk("Mem-info:\n");
98 show_free_areas(filter);
99
100 for_each_bank (i, mi) {
101 struct membank *bank = &mi->bank[i];
102 unsigned int pfn1, pfn2;
103 struct page *page, *end;
104
105 pfn1 = bank_pfn_start(bank);
106 pfn2 = bank_pfn_end(bank);
107
108 page = pfn_to_page(pfn1);
109 end = pfn_to_page(pfn2 - 1) + 1;
110
111 do {
112 total++;
113 if (PageReserved(page))
114 reserved++;
115 else if (PageSwapCache(page))
116 cached++;
117 else if (PageSlab(page))
118 slab++;
119 else if (!page_count(page))
120 free++;
121 else
122 shared += page_count(page) - 1;
123 page++;
124 } while (page < end);
125 }
126
127 printk("%d pages of RAM\n", total);
128 printk("%d free pages\n", free);
129 printk("%d reserved pages\n", reserved);
130 printk("%d slab pages\n", slab);
131 printk("%d pages shared\n", shared);
132 printk("%d pages swap cached\n", cached);
133}
134
135static void __init find_limits(unsigned long *min, unsigned long *max_low,
136 unsigned long *max_high)
137{
138 struct meminfo *mi = &meminfo;
139 int i;
140
141 *min = -1UL;
142 *max_low = *max_high = 0;
143
144 for_each_bank (i, mi) {
145 struct membank *bank = &mi->bank[i];
146 unsigned long start, end;
147
148 start = bank_pfn_start(bank);
149 end = bank_pfn_end(bank);
150
151 if (*min > start)
152 *min = start;
153 if (*max_high < end)
154 *max_high = end;
155 if (bank->highmem)
156 continue;
157 if (*max_low < end)
158 *max_low = end;
159 }
160}
161
162static void __init arm_bootmem_init(unsigned long start_pfn,
163 unsigned long end_pfn)
164{
165 struct memblock_region *reg;
166 unsigned int boot_pages;
167 phys_addr_t bitmap;
168 pg_data_t *pgdat;
169
170 /*
171 * Allocate the bootmem bitmap page. This must be in a region
172 * of memory which has already been mapped.
173 */
174 boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
175 bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES,
176 __pfn_to_phys(end_pfn));
177
178 /*
179 * Initialise the bootmem allocator, handing the
180 * memory banks over to bootmem.
181 */
182 node_set_online(0);
183 pgdat = NODE_DATA(0);
184 init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn);
185
186 /* Free the lowmem regions from memblock into bootmem. */
187 for_each_memblock(memory, reg) {
188 unsigned long start = memblock_region_memory_base_pfn(reg);
189 unsigned long end = memblock_region_memory_end_pfn(reg);
190
191 if (end >= end_pfn)
192 end = end_pfn;
193 if (start >= end)
194 break;
195
196 free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT);
197 }
198
199 /* Reserve the lowmem memblock reserved regions in bootmem. */
200 for_each_memblock(reserved, reg) {
201 unsigned long start = memblock_region_reserved_base_pfn(reg);
202 unsigned long end = memblock_region_reserved_end_pfn(reg);
203
204 if (end >= end_pfn)
205 end = end_pfn;
206 if (start >= end)
207 break;
208
209 reserve_bootmem(__pfn_to_phys(start),
210 (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT);
211 }
212}
213
214#ifdef CONFIG_ZONE_DMA
215
216unsigned long arm_dma_zone_size __read_mostly;
217EXPORT_SYMBOL(arm_dma_zone_size);
218
219/*
220 * The DMA mask corresponding to the maximum bus address allocatable
221 * using GFP_DMA. The default here places no restriction on DMA
222 * allocations. This must be the smallest DMA mask in the system,
223 * so a successful GFP_DMA allocation will always satisfy this.
224 */
225u32 arm_dma_limit;
226
227static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
228 unsigned long dma_size)
229{
230 if (size[0] <= dma_size)
231 return;
232
233 size[ZONE_NORMAL] = size[0] - dma_size;
234 size[ZONE_DMA] = dma_size;
235 hole[ZONE_NORMAL] = hole[0];
236 hole[ZONE_DMA] = 0;
237}
238#endif
239
240static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
241 unsigned long max_high)
242{
243 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
244 struct memblock_region *reg;
245
246 /*
247 * initialise the zones.
248 */
249 memset(zone_size, 0, sizeof(zone_size));
250
251 /*
252 * The memory size has already been determined. If we need
253 * to do anything fancy with the allocation of this memory
254 * to the zones, now is the time to do it.
255 */
256 zone_size[0] = max_low - min;
257#ifdef CONFIG_HIGHMEM
258 zone_size[ZONE_HIGHMEM] = max_high - max_low;
259#endif
260
261 /*
262 * Calculate the size of the holes.
263 * holes = node_size - sum(bank_sizes)
264 */
265 memcpy(zhole_size, zone_size, sizeof(zhole_size));
266 for_each_memblock(memory, reg) {
267 unsigned long start = memblock_region_memory_base_pfn(reg);
268 unsigned long end = memblock_region_memory_end_pfn(reg);
269
270 if (start < max_low) {
271 unsigned long low_end = min(end, max_low);
272 zhole_size[0] -= low_end - start;
273 }
274#ifdef CONFIG_HIGHMEM
275 if (end > max_low) {
276 unsigned long high_start = max(start, max_low);
277 zhole_size[ZONE_HIGHMEM] -= end - high_start;
278 }
279#endif
280 }
281
282#ifdef CONFIG_ZONE_DMA
283 /*
284 * Adjust the sizes according to any special requirements for
285 * this machine type.
286 */
287 if (arm_dma_zone_size) {
288 arm_adjust_dma_zone(zone_size, zhole_size,
289 arm_dma_zone_size >> PAGE_SHIFT);
290 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
291 } else
292 arm_dma_limit = 0xffffffff;
293#endif
294
295 free_area_init_node(0, zone_size, min, zhole_size);
296}
297
298#ifdef CONFIG_HAVE_ARCH_PFN_VALID
299int pfn_valid(unsigned long pfn)
300{
301 return memblock_is_memory(__pfn_to_phys(pfn));
302}
303EXPORT_SYMBOL(pfn_valid);
304#endif
305
306#ifndef CONFIG_SPARSEMEM
307static void arm_memory_present(void)
308{
309}
310#else
311static void arm_memory_present(void)
312{
313 struct memblock_region *reg;
314
315 for_each_memblock(memory, reg)
316 memory_present(0, memblock_region_memory_base_pfn(reg),
317 memblock_region_memory_end_pfn(reg));
318}
319#endif
320
321static int __init meminfo_cmp(const void *_a, const void *_b)
322{
323 const struct membank *a = _a, *b = _b;
324 long cmp = bank_pfn_start(a) - bank_pfn_start(b);
325 return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
326}
327
328void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc)
329{
330 int i;
331
332 sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL);
333
334 memblock_init();
335 for (i = 0; i < mi->nr_banks; i++)
336 memblock_add(mi->bank[i].start, mi->bank[i].size);
337
338 /* Register the kernel text, kernel data and initrd with memblock. */
339#ifdef CONFIG_XIP_KERNEL
340 memblock_reserve(__pa(_sdata), _end - _sdata);
341#else
342 memblock_reserve(__pa(_stext), _end - _stext);
343#endif
344#ifdef CONFIG_BLK_DEV_INITRD
345 if (phys_initrd_size &&
346 !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
347 pr_err("INITRD: 0x%08lx+0x%08lx is not a memory region - disabling initrd\n",
348 phys_initrd_start, phys_initrd_size);
349 phys_initrd_start = phys_initrd_size = 0;
350 }
351 if (phys_initrd_size &&
352 memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
353 pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region - disabling initrd\n",
354 phys_initrd_start, phys_initrd_size);
355 phys_initrd_start = phys_initrd_size = 0;
356 }
357 if (phys_initrd_size) {
358 memblock_reserve(phys_initrd_start, phys_initrd_size);
359
360 /* Now convert initrd to virtual addresses */
361 initrd_start = __phys_to_virt(phys_initrd_start);
362 initrd_end = initrd_start + phys_initrd_size;
363 }
364#endif
365
366 arm_mm_memblock_reserve();
367 arm_dt_memblock_reserve();
368
369 /* reserve any platform specific memblock areas */
370 if (mdesc->reserve)
371 mdesc->reserve();
372
373 memblock_analyze();
374 memblock_dump_all();
375}
376
377void __init bootmem_init(void)
378{
379 unsigned long min, max_low, max_high;
380
381 max_low = max_high = 0;
382
383 find_limits(&min, &max_low, &max_high);
384
385 arm_bootmem_init(min, max_low);
386
387 /*
388 * Sparsemem tries to allocate bootmem in memory_present(),
389 * so must be done after the fixed reservations
390 */
391 arm_memory_present();
392
393 /*
394 * sparse_init() needs the bootmem allocator up and running.
395 */
396 sparse_init();
397
398 /*
399 * Now free the memory - free_area_init_node needs
400 * the sparse mem_map arrays initialized by sparse_init()
401 * for memmap_init_zone(), otherwise all PFNs are invalid.
402 */
403 arm_bootmem_free(min, max_low, max_high);
404
405 high_memory = __va(((phys_addr_t)max_low << PAGE_SHIFT) - 1) + 1;
406
407 /*
408 * This doesn't seem to be used by the Linux memory manager any
409 * more, but is used by ll_rw_block. If we can get rid of it, we
410 * also get rid of some of the stuff above as well.
411 *
412 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
413 * the system, not the maximum PFN.
414 */
415 max_low_pfn = max_low - PHYS_PFN_OFFSET;
416 max_pfn = max_high - PHYS_PFN_OFFSET;
417}
418
419static inline int free_area(unsigned long pfn, unsigned long end, char *s)
420{
421 unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
422
423 for (; pfn < end; pfn++) {
424 struct page *page = pfn_to_page(pfn);
425 ClearPageReserved(page);
426 init_page_count(page);
427 __free_page(page);
428 pages++;
429 }
430
431 if (size && s)
432 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
433
434 return pages;
435}
436
437/*
438 * Poison init memory with an undefined instruction (ARM) or a branch to an
439 * undefined instruction (Thumb).
440 */
441static inline void poison_init_mem(void *s, size_t count)
442{
443 u32 *p = (u32 *)s;
444 for (; count != 0; count -= 4)
445 *p++ = 0xe7fddef0;
446}
447
448static inline void
449free_memmap(unsigned long start_pfn, unsigned long end_pfn)
450{
451 struct page *start_pg, *end_pg;
452 unsigned long pg, pgend;
453
454 /*
455 * Convert start_pfn/end_pfn to a struct page pointer.
456 */
457 start_pg = pfn_to_page(start_pfn - 1) + 1;
458 end_pg = pfn_to_page(end_pfn - 1) + 1;
459
460 /*
461 * Convert to physical addresses, and
462 * round start upwards and end downwards.
463 */
464 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
465 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
466
467 /*
468 * If there are free pages between these,
469 * free the section of the memmap array.
470 */
471 if (pg < pgend)
472 free_bootmem(pg, pgend - pg);
473}
474
475/*
476 * The mem_map array can get very big. Free the unused area of the memory map.
477 */
478static void __init free_unused_memmap(struct meminfo *mi)
479{
480 unsigned long bank_start, prev_bank_end = 0;
481 unsigned int i;
482
483 /*
484 * This relies on each bank being in address order.
485 * The banks are sorted previously in bootmem_init().
486 */
487 for_each_bank(i, mi) {
488 struct membank *bank = &mi->bank[i];
489
490 bank_start = bank_pfn_start(bank);
491
492#ifdef CONFIG_SPARSEMEM
493 /*
494 * Take care not to free memmap entries that don't exist
495 * due to SPARSEMEM sections which aren't present.
496 */
497 bank_start = min(bank_start,
498 ALIGN(prev_bank_end, PAGES_PER_SECTION));
499#else
500 /*
501 * Align down here since the VM subsystem insists that the
502 * memmap entries are valid from the bank start aligned to
503 * MAX_ORDER_NR_PAGES.
504 */
505 bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
506#endif
507 /*
508 * If we had a previous bank, and there is a space
509 * between the current bank and the previous, free it.
510 */
511 if (prev_bank_end && prev_bank_end < bank_start)
512 free_memmap(prev_bank_end, bank_start);
513
514 /*
515 * Align up here since the VM subsystem insists that the
516 * memmap entries are valid from the bank end aligned to
517 * MAX_ORDER_NR_PAGES.
518 */
519 prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
520 }
521
522#ifdef CONFIG_SPARSEMEM
523 if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
524 free_memmap(prev_bank_end,
525 ALIGN(prev_bank_end, PAGES_PER_SECTION));
526#endif
527}
528
529static void __init free_highpages(void)
530{
531#ifdef CONFIG_HIGHMEM
532 unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET;
533 struct memblock_region *mem, *res;
534
535 /* set highmem page free */
536 for_each_memblock(memory, mem) {
537 unsigned long start = memblock_region_memory_base_pfn(mem);
538 unsigned long end = memblock_region_memory_end_pfn(mem);
539
540 /* Ignore complete lowmem entries */
541 if (end <= max_low)
542 continue;
543
544 /* Truncate partial highmem entries */
545 if (start < max_low)
546 start = max_low;
547
548 /* Find and exclude any reserved regions */
549 for_each_memblock(reserved, res) {
550 unsigned long res_start, res_end;
551
552 res_start = memblock_region_reserved_base_pfn(res);
553 res_end = memblock_region_reserved_end_pfn(res);
554
555 if (res_end < start)
556 continue;
557 if (res_start < start)
558 res_start = start;
559 if (res_start > end)
560 res_start = end;
561 if (res_end > end)
562 res_end = end;
563 if (res_start != start)
564 totalhigh_pages += free_area(start, res_start,
565 NULL);
566 start = res_end;
567 if (start == end)
568 break;
569 }
570
571 /* And now free anything which remains */
572 if (start < end)
573 totalhigh_pages += free_area(start, end, NULL);
574 }
575 totalram_pages += totalhigh_pages;
576#endif
577}
578
579/*
580 * mem_init() marks the free areas in the mem_map and tells us how much
581 * memory is free. This is done after various parts of the system have
582 * claimed their memory after the kernel image.
583 */
584void __init mem_init(void)
585{
586 unsigned long reserved_pages, free_pages;
587 struct memblock_region *reg;
588 int i;
589#ifdef CONFIG_HAVE_TCM
590 /* These pointers are filled in on TCM detection */
591 extern u32 dtcm_end;
592 extern u32 itcm_end;
593#endif
594
595 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
596
597 /* this will put all unused low memory onto the freelists */
598 free_unused_memmap(&meminfo);
599
600 totalram_pages += free_all_bootmem();
601
602#ifdef CONFIG_SA1111
603 /* now that our DMA memory is actually so designated, we can free it */
604 totalram_pages += free_area(PHYS_PFN_OFFSET,
605 __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
606#endif
607
608 free_highpages();
609
610 reserved_pages = free_pages = 0;
611
612 for_each_bank(i, &meminfo) {
613 struct membank *bank = &meminfo.bank[i];
614 unsigned int pfn1, pfn2;
615 struct page *page, *end;
616
617 pfn1 = bank_pfn_start(bank);
618 pfn2 = bank_pfn_end(bank);
619
620 page = pfn_to_page(pfn1);
621 end = pfn_to_page(pfn2 - 1) + 1;
622
623 do {
624 if (PageReserved(page))
625 reserved_pages++;
626 else if (!page_count(page))
627 free_pages++;
628 page++;
629 } while (page < end);
630 }
631
632 /*
633 * Since our memory may not be contiguous, calculate the
634 * real number of pages we have in this system
635 */
636 printk(KERN_INFO "Memory:");
637 num_physpages = 0;
638 for_each_memblock(memory, reg) {
639 unsigned long pages = memblock_region_memory_end_pfn(reg) -
640 memblock_region_memory_base_pfn(reg);
641 num_physpages += pages;
642 printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
643 }
644 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
645
646 printk(KERN_NOTICE "Memory: %luk/%luk available, %luk reserved, %luK highmem\n",
647 nr_free_pages() << (PAGE_SHIFT-10),
648 free_pages << (PAGE_SHIFT-10),
649 reserved_pages << (PAGE_SHIFT-10),
650 totalhigh_pages << (PAGE_SHIFT-10));
651
652#define MLK(b, t) b, t, ((t) - (b)) >> 10
653#define MLM(b, t) b, t, ((t) - (b)) >> 20
654#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
655
656 printk(KERN_NOTICE "Virtual kernel memory layout:\n"
657 " vector : 0x%08lx - 0x%08lx (%4ld kB)\n"
658#ifdef CONFIG_HAVE_TCM
659 " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
660 " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
661#endif
662 " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
663#ifdef CONFIG_MMU
664 " DMA : 0x%08lx - 0x%08lx (%4ld MB)\n"
665#endif
666 " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
667 " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n"
668#ifdef CONFIG_HIGHMEM
669 " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n"
670#endif
671 " modules : 0x%08lx - 0x%08lx (%4ld MB)\n"
672 " .text : 0x%p" " - 0x%p" " (%4d kB)\n"
673 " .init : 0x%p" " - 0x%p" " (%4d kB)\n"
674 " .data : 0x%p" " - 0x%p" " (%4d kB)\n"
675 " .bss : 0x%p" " - 0x%p" " (%4d kB)\n",
676
677 MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
678 (PAGE_SIZE)),
679#ifdef CONFIG_HAVE_TCM
680 MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
681 MLK(ITCM_OFFSET, (unsigned long) itcm_end),
682#endif
683 MLK(FIXADDR_START, FIXADDR_TOP),
684#ifdef CONFIG_MMU
685 MLM(CONSISTENT_BASE, CONSISTENT_END),
686#endif
687 MLM(VMALLOC_START, VMALLOC_END),
688 MLM(PAGE_OFFSET, (unsigned long)high_memory),
689#ifdef CONFIG_HIGHMEM
690 MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
691 (PAGE_SIZE)),
692#endif
693 MLM(MODULES_VADDR, MODULES_END),
694
695 MLK_ROUNDUP(_text, _etext),
696 MLK_ROUNDUP(__init_begin, __init_end),
697 MLK_ROUNDUP(_sdata, _edata),
698 MLK_ROUNDUP(__bss_start, __bss_stop));
699
700#undef MLK
701#undef MLM
702#undef MLK_ROUNDUP
703
704 /*
705 * Check boundaries twice: Some fundamental inconsistencies can
706 * be detected at build time already.
707 */
708#ifdef CONFIG_MMU
709 BUILD_BUG_ON(VMALLOC_END > CONSISTENT_BASE);
710 BUG_ON(VMALLOC_END > CONSISTENT_BASE);
711
712 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
713 BUG_ON(TASK_SIZE > MODULES_VADDR);
714#endif
715
716#ifdef CONFIG_HIGHMEM
717 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
718 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
719#endif
720
721 if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
722 extern int sysctl_overcommit_memory;
723 /*
724 * On a machine this small we won't get
725 * anywhere without overcommit, so turn
726 * it on by default.
727 */
728 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
729 }
730}
731
732void free_initmem(void)
733{
734#ifdef CONFIG_HAVE_TCM
735 extern char __tcm_start, __tcm_end;
736
737 poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
738 totalram_pages += free_area(__phys_to_pfn(__pa(&__tcm_start)),
739 __phys_to_pfn(__pa(&__tcm_end)),
740 "TCM link");
741#endif
742
743 poison_init_mem(__init_begin, __init_end - __init_begin);
744 if (!machine_is_integrator() && !machine_is_cintegrator())
745 totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
746 __phys_to_pfn(__pa(__init_end)),
747 "init");
748}
749
750#ifdef CONFIG_BLK_DEV_INITRD
751
752static int keep_initrd;
753
754void free_initrd_mem(unsigned long start, unsigned long end)
755{
756 if (!keep_initrd) {
757 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
758 totalram_pages += free_area(__phys_to_pfn(__pa(start)),
759 __phys_to_pfn(__pa(end)),
760 "initrd");
761 }
762}
763
764static int __init keepinitrd_setup(char *__unused)
765{
766 keep_initrd = 1;
767 return 1;
768}
769
770__setup("keepinitrd", keepinitrd_setup);
771#endif
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/mm/init.c
4 *
5 * Copyright (C) 1995-2005 Russell King
6 */
7#include <linux/kernel.h>
8#include <linux/errno.h>
9#include <linux/swap.h>
10#include <linux/init.h>
11#include <linux/mman.h>
12#include <linux/sched/signal.h>
13#include <linux/sched/task.h>
14#include <linux/export.h>
15#include <linux/nodemask.h>
16#include <linux/initrd.h>
17#include <linux/of_fdt.h>
18#include <linux/highmem.h>
19#include <linux/gfp.h>
20#include <linux/memblock.h>
21#include <linux/dma-map-ops.h>
22#include <linux/sizes.h>
23#include <linux/stop_machine.h>
24#include <linux/swiotlb.h>
25#include <linux/execmem.h>
26
27#include <asm/cp15.h>
28#include <asm/mach-types.h>
29#include <asm/memblock.h>
30#include <asm/page.h>
31#include <asm/prom.h>
32#include <asm/sections.h>
33#include <asm/setup.h>
34#include <asm/set_memory.h>
35#include <asm/system_info.h>
36#include <asm/tlb.h>
37#include <asm/fixmap.h>
38#include <asm/ptdump.h>
39
40#include <asm/mach/arch.h>
41#include <asm/mach/map.h>
42
43#include "mm.h"
44
45#ifdef CONFIG_CPU_CP15_MMU
46unsigned long __init __clear_cr(unsigned long mask)
47{
48 cr_alignment = cr_alignment & ~mask;
49 return cr_alignment;
50}
51#endif
52
53#ifdef CONFIG_BLK_DEV_INITRD
54static int __init parse_tag_initrd(const struct tag *tag)
55{
56 pr_warn("ATAG_INITRD is deprecated; "
57 "please update your bootloader.\n");
58 phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
59 phys_initrd_size = tag->u.initrd.size;
60 return 0;
61}
62
63__tagtable(ATAG_INITRD, parse_tag_initrd);
64
65static int __init parse_tag_initrd2(const struct tag *tag)
66{
67 phys_initrd_start = tag->u.initrd.start;
68 phys_initrd_size = tag->u.initrd.size;
69 return 0;
70}
71
72__tagtable(ATAG_INITRD2, parse_tag_initrd2);
73#endif
74
75static void __init find_limits(unsigned long *min, unsigned long *max_low,
76 unsigned long *max_high)
77{
78 *max_low = PFN_DOWN(memblock_get_current_limit());
79 *min = PFN_UP(memblock_start_of_DRAM());
80 *max_high = PFN_DOWN(memblock_end_of_DRAM());
81}
82
83#ifdef CONFIG_ZONE_DMA
84
85phys_addr_t arm_dma_zone_size __read_mostly;
86EXPORT_SYMBOL(arm_dma_zone_size);
87
88/*
89 * The DMA mask corresponding to the maximum bus address allocatable
90 * using GFP_DMA. The default here places no restriction on DMA
91 * allocations. This must be the smallest DMA mask in the system,
92 * so a successful GFP_DMA allocation will always satisfy this.
93 */
94phys_addr_t arm_dma_limit;
95unsigned long arm_dma_pfn_limit;
96#endif
97
98void __init setup_dma_zone(const struct machine_desc *mdesc)
99{
100#ifdef CONFIG_ZONE_DMA
101 if (mdesc->dma_zone_size) {
102 arm_dma_zone_size = mdesc->dma_zone_size;
103 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
104 } else
105 arm_dma_limit = 0xffffffff;
106 arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
107#endif
108}
109
110static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
111 unsigned long max_high)
112{
113 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
114
115#ifdef CONFIG_ZONE_DMA
116 max_zone_pfn[ZONE_DMA] = min(arm_dma_pfn_limit, max_low);
117#endif
118 max_zone_pfn[ZONE_NORMAL] = max_low;
119#ifdef CONFIG_HIGHMEM
120 max_zone_pfn[ZONE_HIGHMEM] = max_high;
121#endif
122 free_area_init(max_zone_pfn);
123}
124
125#ifdef CONFIG_HAVE_ARCH_PFN_VALID
126int pfn_valid(unsigned long pfn)
127{
128 phys_addr_t addr = __pfn_to_phys(pfn);
129 unsigned long pageblock_size = PAGE_SIZE * pageblock_nr_pages;
130
131 if (__phys_to_pfn(addr) != pfn)
132 return 0;
133
134 /*
135 * If address less than pageblock_size bytes away from a present
136 * memory chunk there still will be a memory map entry for it
137 * because we round freed memory map to the pageblock boundaries.
138 */
139 if (memblock_overlaps_region(&memblock.memory,
140 ALIGN_DOWN(addr, pageblock_size),
141 pageblock_size))
142 return 1;
143
144 return 0;
145}
146EXPORT_SYMBOL(pfn_valid);
147#endif
148
149static bool arm_memblock_steal_permitted = true;
150
151phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
152{
153 phys_addr_t phys;
154
155 BUG_ON(!arm_memblock_steal_permitted);
156
157 phys = memblock_phys_alloc(size, align);
158 if (!phys)
159 panic("Failed to steal %pa bytes at %pS\n",
160 &size, (void *)_RET_IP_);
161
162 memblock_phys_free(phys, size);
163 memblock_remove(phys, size);
164
165 return phys;
166}
167
168#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
169void check_cpu_icache_size(int cpuid)
170{
171 u32 size, ctr;
172
173 asm("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
174
175 size = 1 << ((ctr & 0xf) + 2);
176 if (cpuid != 0 && icache_size != size)
177 pr_info("CPU%u: detected I-Cache line size mismatch, workaround enabled\n",
178 cpuid);
179 if (icache_size > size)
180 icache_size = size;
181}
182#endif
183
184void __init arm_memblock_init(const struct machine_desc *mdesc)
185{
186 /* Register the kernel text, kernel data and initrd with memblock. */
187 memblock_reserve(__pa(KERNEL_START), KERNEL_END - KERNEL_START);
188
189 reserve_initrd_mem();
190
191 arm_mm_memblock_reserve();
192
193 /* reserve any platform specific memblock areas */
194 if (mdesc->reserve)
195 mdesc->reserve();
196
197 early_init_fdt_scan_reserved_mem();
198
199 /* reserve memory for DMA contiguous allocations */
200 dma_contiguous_reserve(arm_dma_limit);
201
202 arm_memblock_steal_permitted = false;
203 memblock_dump_all();
204}
205
206void __init bootmem_init(void)
207{
208 memblock_allow_resize();
209
210 find_limits(&min_low_pfn, &max_low_pfn, &max_pfn);
211
212 early_memtest((phys_addr_t)min_low_pfn << PAGE_SHIFT,
213 (phys_addr_t)max_low_pfn << PAGE_SHIFT);
214
215 /*
216 * sparse_init() tries to allocate memory from memblock, so must be
217 * done after the fixed reservations
218 */
219 sparse_init();
220
221 /*
222 * Now free the memory - free_area_init needs
223 * the sparse mem_map arrays initialized by sparse_init()
224 * for memmap_init_zone(), otherwise all PFNs are invalid.
225 */
226 zone_sizes_init(min_low_pfn, max_low_pfn, max_pfn);
227}
228
229/*
230 * Poison init memory with an undefined instruction (ARM) or a branch to an
231 * undefined instruction (Thumb).
232 */
233static inline void poison_init_mem(void *s, size_t count)
234{
235 u32 *p = (u32 *)s;
236 for (; count != 0; count -= 4)
237 *p++ = 0xe7fddef0;
238}
239
240static void __init free_highpages(void)
241{
242#ifdef CONFIG_HIGHMEM
243 unsigned long max_low = max_low_pfn;
244 phys_addr_t range_start, range_end;
245 u64 i;
246
247 /* set highmem page free */
248 for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
249 &range_start, &range_end, NULL) {
250 unsigned long start = PFN_UP(range_start);
251 unsigned long end = PFN_DOWN(range_end);
252
253 /* Ignore complete lowmem entries */
254 if (end <= max_low)
255 continue;
256
257 /* Truncate partial highmem entries */
258 if (start < max_low)
259 start = max_low;
260
261 for (; start < end; start++)
262 free_highmem_page(pfn_to_page(start));
263 }
264#endif
265}
266
267/*
268 * mem_init() marks the free areas in the mem_map and tells us how much
269 * memory is free. This is done after various parts of the system have
270 * claimed their memory after the kernel image.
271 */
272void __init mem_init(void)
273{
274#ifdef CONFIG_ARM_LPAE
275 swiotlb_init(max_pfn > arm_dma_pfn_limit, SWIOTLB_VERBOSE);
276#endif
277
278 set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
279
280 /* this will put all unused low memory onto the freelists */
281 memblock_free_all();
282
283#ifdef CONFIG_SA1111
284 /* now that our DMA memory is actually so designated, we can free it */
285 free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
286#endif
287
288 free_highpages();
289
290 /*
291 * Check boundaries twice: Some fundamental inconsistencies can
292 * be detected at build time already.
293 */
294#ifdef CONFIG_MMU
295 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
296 BUG_ON(TASK_SIZE > MODULES_VADDR);
297#endif
298
299#ifdef CONFIG_HIGHMEM
300 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
301 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
302#endif
303}
304
305#ifdef CONFIG_STRICT_KERNEL_RWX
306struct section_perm {
307 const char *name;
308 unsigned long start;
309 unsigned long end;
310 pmdval_t mask;
311 pmdval_t prot;
312 pmdval_t clear;
313};
314
315/* First section-aligned location at or after __start_rodata. */
316extern char __start_rodata_section_aligned[];
317
318static struct section_perm nx_perms[] = {
319 /* Make pages tables, etc before _stext RW (set NX). */
320 {
321 .name = "pre-text NX",
322 .start = PAGE_OFFSET,
323 .end = (unsigned long)_stext,
324 .mask = ~PMD_SECT_XN,
325 .prot = PMD_SECT_XN,
326 },
327 /* Make init RW (set NX). */
328 {
329 .name = "init NX",
330 .start = (unsigned long)__init_begin,
331 .end = (unsigned long)_sdata,
332 .mask = ~PMD_SECT_XN,
333 .prot = PMD_SECT_XN,
334 },
335 /* Make rodata NX (set RO in ro_perms below). */
336 {
337 .name = "rodata NX",
338 .start = (unsigned long)__start_rodata_section_aligned,
339 .end = (unsigned long)__init_begin,
340 .mask = ~PMD_SECT_XN,
341 .prot = PMD_SECT_XN,
342 },
343};
344
345static struct section_perm ro_perms[] = {
346 /* Make kernel code and rodata RX (set RO). */
347 {
348 .name = "text/rodata RO",
349 .start = (unsigned long)_stext,
350 .end = (unsigned long)__init_begin,
351#ifdef CONFIG_ARM_LPAE
352 .mask = ~(L_PMD_SECT_RDONLY | PMD_SECT_AP2),
353 .prot = L_PMD_SECT_RDONLY | PMD_SECT_AP2,
354#else
355 .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
356 .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE,
357 .clear = PMD_SECT_AP_WRITE,
358#endif
359 },
360};
361
362/*
363 * Updates section permissions only for the current mm (sections are
364 * copied into each mm). During startup, this is the init_mm. Is only
365 * safe to be called with preemption disabled, as under stop_machine().
366 */
367static inline void section_update(unsigned long addr, pmdval_t mask,
368 pmdval_t prot, struct mm_struct *mm)
369{
370 pmd_t *pmd;
371
372 pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset(mm, addr), addr), addr), addr);
373
374#ifdef CONFIG_ARM_LPAE
375 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
376#else
377 if (addr & SECTION_SIZE)
378 pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
379 else
380 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
381#endif
382 flush_pmd_entry(pmd);
383 local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
384}
385
386/* Make sure extended page tables are in use. */
387static inline bool arch_has_strict_perms(void)
388{
389 if (cpu_architecture() < CPU_ARCH_ARMv6)
390 return false;
391
392 return !!(get_cr() & CR_XP);
393}
394
395static void set_section_perms(struct section_perm *perms, int n, bool set,
396 struct mm_struct *mm)
397{
398 size_t i;
399 unsigned long addr;
400
401 if (!arch_has_strict_perms())
402 return;
403
404 for (i = 0; i < n; i++) {
405 if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||
406 !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {
407 pr_err("BUG: %s section %lx-%lx not aligned to %lx\n",
408 perms[i].name, perms[i].start, perms[i].end,
409 SECTION_SIZE);
410 continue;
411 }
412
413 for (addr = perms[i].start;
414 addr < perms[i].end;
415 addr += SECTION_SIZE)
416 section_update(addr, perms[i].mask,
417 set ? perms[i].prot : perms[i].clear, mm);
418 }
419
420}
421
422/*
423 * update_sections_early intended to be called only through stop_machine
424 * framework and executed by only one CPU while all other CPUs will spin and
425 * wait, so no locking is required in this function.
426 */
427static void update_sections_early(struct section_perm perms[], int n)
428{
429 struct task_struct *t, *s;
430
431 for_each_process(t) {
432 if (t->flags & PF_KTHREAD)
433 continue;
434 for_each_thread(t, s)
435 if (s->mm)
436 set_section_perms(perms, n, true, s->mm);
437 }
438 set_section_perms(perms, n, true, current->active_mm);
439 set_section_perms(perms, n, true, &init_mm);
440}
441
442static int __fix_kernmem_perms(void *unused)
443{
444 update_sections_early(nx_perms, ARRAY_SIZE(nx_perms));
445 return 0;
446}
447
448static void fix_kernmem_perms(void)
449{
450 stop_machine(__fix_kernmem_perms, NULL, NULL);
451}
452
453static int __mark_rodata_ro(void *unused)
454{
455 update_sections_early(ro_perms, ARRAY_SIZE(ro_perms));
456 return 0;
457}
458
459void mark_rodata_ro(void)
460{
461 stop_machine(__mark_rodata_ro, NULL, NULL);
462 arm_debug_checkwx();
463}
464
465#else
466static inline void fix_kernmem_perms(void) { }
467#endif /* CONFIG_STRICT_KERNEL_RWX */
468
469void free_initmem(void)
470{
471 fix_kernmem_perms();
472
473 poison_init_mem(__init_begin, __init_end - __init_begin);
474 if (!machine_is_integrator() && !machine_is_cintegrator())
475 free_initmem_default(-1);
476}
477
478#ifdef CONFIG_BLK_DEV_INITRD
479void free_initrd_mem(unsigned long start, unsigned long end)
480{
481 if (start == initrd_start)
482 start = round_down(start, PAGE_SIZE);
483 if (end == initrd_end)
484 end = round_up(end, PAGE_SIZE);
485
486 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
487 free_reserved_area((void *)start, (void *)end, -1, "initrd");
488}
489#endif
490
491#ifdef CONFIG_EXECMEM
492
493#ifdef CONFIG_XIP_KERNEL
494/*
495 * The XIP kernel text is mapped in the module area for modules and
496 * some other stuff to work without any indirect relocations.
497 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
498 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
499 */
500#undef MODULES_VADDR
501#define MODULES_VADDR (((unsigned long)_exiprom + ~PMD_MASK) & PMD_MASK)
502#endif
503
504#ifdef CONFIG_MMU
505static struct execmem_info execmem_info __ro_after_init;
506
507struct execmem_info __init *execmem_arch_setup(void)
508{
509 unsigned long fallback_start = 0, fallback_end = 0;
510
511 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS)) {
512 fallback_start = VMALLOC_START;
513 fallback_end = VMALLOC_END;
514 }
515
516 execmem_info = (struct execmem_info){
517 .ranges = {
518 [EXECMEM_DEFAULT] = {
519 .start = MODULES_VADDR,
520 .end = MODULES_END,
521 .pgprot = PAGE_KERNEL_EXEC,
522 .alignment = 1,
523 .fallback_start = fallback_start,
524 .fallback_end = fallback_end,
525 },
526 },
527 };
528
529 return &execmem_info;
530}
531#endif /* CONFIG_MMU */
532
533#endif /* CONFIG_EXECMEM */