xref: /openbmc/linux/arch/arm/mm/init.c (revision 37be287c)
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/export.h>
17 #include <linux/nodemask.h>
18 #include <linux/initrd.h>
19 #include <linux/of_fdt.h>
20 #include <linux/highmem.h>
21 #include <linux/gfp.h>
22 #include <linux/memblock.h>
23 #include <linux/dma-contiguous.h>
24 #include <linux/sizes.h>
25 
26 #include <asm/mach-types.h>
27 #include <asm/memblock.h>
28 #include <asm/prom.h>
29 #include <asm/sections.h>
30 #include <asm/setup.h>
31 #include <asm/tlb.h>
32 #include <asm/fixmap.h>
33 
34 #include <asm/mach/arch.h>
35 #include <asm/mach/map.h>
36 
37 #include "mm.h"
38 
39 static phys_addr_t phys_initrd_start __initdata = 0;
40 static unsigned long phys_initrd_size __initdata = 0;
41 
42 static int __init early_initrd(char *p)
43 {
44 	phys_addr_t start;
45 	unsigned long size;
46 	char *endp;
47 
48 	start = memparse(p, &endp);
49 	if (*endp == ',') {
50 		size = memparse(endp + 1, NULL);
51 
52 		phys_initrd_start = start;
53 		phys_initrd_size = size;
54 	}
55 	return 0;
56 }
57 early_param("initrd", early_initrd);
58 
59 static int __init parse_tag_initrd(const struct tag *tag)
60 {
61 	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
62 		"please update your bootloader.\n");
63 	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
64 	phys_initrd_size = tag->u.initrd.size;
65 	return 0;
66 }
67 
68 __tagtable(ATAG_INITRD, parse_tag_initrd);
69 
70 static int __init parse_tag_initrd2(const struct tag *tag)
71 {
72 	phys_initrd_start = tag->u.initrd.start;
73 	phys_initrd_size = tag->u.initrd.size;
74 	return 0;
75 }
76 
77 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
78 
79 /*
80  * This keeps memory configuration data used by a couple memory
81  * initialization functions, as well as show_mem() for the skipping
82  * of holes in the memory map.  It is populated by arm_add_memory().
83  */
84 struct meminfo meminfo;
85 
86 void show_mem(unsigned int filter)
87 {
88 	int free = 0, total = 0, reserved = 0;
89 	int shared = 0, cached = 0, slab = 0, i;
90 	struct meminfo * mi = &meminfo;
91 
92 	printk("Mem-info:\n");
93 	show_free_areas(filter);
94 
95 	for_each_bank (i, mi) {
96 		struct membank *bank = &mi->bank[i];
97 		unsigned int pfn1, pfn2;
98 		struct page *page, *end;
99 
100 		pfn1 = bank_pfn_start(bank);
101 		pfn2 = bank_pfn_end(bank);
102 
103 		page = pfn_to_page(pfn1);
104 		end  = pfn_to_page(pfn2 - 1) + 1;
105 
106 		do {
107 			total++;
108 			if (PageReserved(page))
109 				reserved++;
110 			else if (PageSwapCache(page))
111 				cached++;
112 			else if (PageSlab(page))
113 				slab++;
114 			else if (!page_count(page))
115 				free++;
116 			else
117 				shared += page_count(page) - 1;
118 			page++;
119 		} while (page < end);
120 	}
121 
122 	printk("%d pages of RAM\n", total);
123 	printk("%d free pages\n", free);
124 	printk("%d reserved pages\n", reserved);
125 	printk("%d slab pages\n", slab);
126 	printk("%d pages shared\n", shared);
127 	printk("%d pages swap cached\n", cached);
128 }
129 
130 static void __init find_limits(unsigned long *min, unsigned long *max_low,
131 			       unsigned long *max_high)
132 {
133 	struct meminfo *mi = &meminfo;
134 	int i;
135 
136 	/* This assumes the meminfo array is properly sorted */
137 	*min = bank_pfn_start(&mi->bank[0]);
138 	for_each_bank (i, mi)
139 		if (mi->bank[i].highmem)
140 				break;
141 	*max_low = bank_pfn_end(&mi->bank[i - 1]);
142 	*max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]);
143 }
144 
145 #ifdef CONFIG_ZONE_DMA
146 
147 phys_addr_t arm_dma_zone_size __read_mostly;
148 EXPORT_SYMBOL(arm_dma_zone_size);
149 
150 /*
151  * The DMA mask corresponding to the maximum bus address allocatable
152  * using GFP_DMA.  The default here places no restriction on DMA
153  * allocations.  This must be the smallest DMA mask in the system,
154  * so a successful GFP_DMA allocation will always satisfy this.
155  */
156 phys_addr_t arm_dma_limit;
157 unsigned long arm_dma_pfn_limit;
158 
159 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
160 	unsigned long dma_size)
161 {
162 	if (size[0] <= dma_size)
163 		return;
164 
165 	size[ZONE_NORMAL] = size[0] - dma_size;
166 	size[ZONE_DMA] = dma_size;
167 	hole[ZONE_NORMAL] = hole[0];
168 	hole[ZONE_DMA] = 0;
169 }
170 #endif
171 
172 void __init setup_dma_zone(const struct machine_desc *mdesc)
173 {
174 #ifdef CONFIG_ZONE_DMA
175 	if (mdesc->dma_zone_size) {
176 		arm_dma_zone_size = mdesc->dma_zone_size;
177 		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
178 	} else
179 		arm_dma_limit = 0xffffffff;
180 	arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
181 #endif
182 }
183 
184 static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
185 	unsigned long max_high)
186 {
187 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
188 	struct memblock_region *reg;
189 
190 	/*
191 	 * initialise the zones.
192 	 */
193 	memset(zone_size, 0, sizeof(zone_size));
194 
195 	/*
196 	 * The memory size has already been determined.  If we need
197 	 * to do anything fancy with the allocation of this memory
198 	 * to the zones, now is the time to do it.
199 	 */
200 	zone_size[0] = max_low - min;
201 #ifdef CONFIG_HIGHMEM
202 	zone_size[ZONE_HIGHMEM] = max_high - max_low;
203 #endif
204 
205 	/*
206 	 * Calculate the size of the holes.
207 	 *  holes = node_size - sum(bank_sizes)
208 	 */
209 	memcpy(zhole_size, zone_size, sizeof(zhole_size));
210 	for_each_memblock(memory, reg) {
211 		unsigned long start = memblock_region_memory_base_pfn(reg);
212 		unsigned long end = memblock_region_memory_end_pfn(reg);
213 
214 		if (start < max_low) {
215 			unsigned long low_end = min(end, max_low);
216 			zhole_size[0] -= low_end - start;
217 		}
218 #ifdef CONFIG_HIGHMEM
219 		if (end > max_low) {
220 			unsigned long high_start = max(start, max_low);
221 			zhole_size[ZONE_HIGHMEM] -= end - high_start;
222 		}
223 #endif
224 	}
225 
226 #ifdef CONFIG_ZONE_DMA
227 	/*
228 	 * Adjust the sizes according to any special requirements for
229 	 * this machine type.
230 	 */
231 	if (arm_dma_zone_size)
232 		arm_adjust_dma_zone(zone_size, zhole_size,
233 			arm_dma_zone_size >> PAGE_SHIFT);
234 #endif
235 
236 	free_area_init_node(0, zone_size, min, zhole_size);
237 }
238 
239 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
240 int pfn_valid(unsigned long pfn)
241 {
242 	return memblock_is_memory(__pfn_to_phys(pfn));
243 }
244 EXPORT_SYMBOL(pfn_valid);
245 #endif
246 
247 #ifndef CONFIG_SPARSEMEM
248 static void __init arm_memory_present(void)
249 {
250 }
251 #else
252 static void __init arm_memory_present(void)
253 {
254 	struct memblock_region *reg;
255 
256 	for_each_memblock(memory, reg)
257 		memory_present(0, memblock_region_memory_base_pfn(reg),
258 			       memblock_region_memory_end_pfn(reg));
259 }
260 #endif
261 
262 static bool arm_memblock_steal_permitted = true;
263 
264 phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
265 {
266 	phys_addr_t phys;
267 
268 	BUG_ON(!arm_memblock_steal_permitted);
269 
270 	phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
271 	memblock_free(phys, size);
272 	memblock_remove(phys, size);
273 
274 	return phys;
275 }
276 
277 void __init arm_memblock_init(struct meminfo *mi,
278 	const struct machine_desc *mdesc)
279 {
280 	int i;
281 
282 	for (i = 0; i < mi->nr_banks; i++)
283 		memblock_add(mi->bank[i].start, mi->bank[i].size);
284 
285 	/* Register the kernel text, kernel data and initrd with memblock. */
286 #ifdef CONFIG_XIP_KERNEL
287 	memblock_reserve(__pa(_sdata), _end - _sdata);
288 #else
289 	memblock_reserve(__pa(_stext), _end - _stext);
290 #endif
291 #ifdef CONFIG_BLK_DEV_INITRD
292 	/* FDT scan will populate initrd_start */
293 	if (initrd_start && !phys_initrd_size) {
294 		phys_initrd_start = __virt_to_phys(initrd_start);
295 		phys_initrd_size = initrd_end - initrd_start;
296 	}
297 	initrd_start = initrd_end = 0;
298 	if (phys_initrd_size &&
299 	    !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
300 		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
301 		       (u64)phys_initrd_start, phys_initrd_size);
302 		phys_initrd_start = phys_initrd_size = 0;
303 	}
304 	if (phys_initrd_size &&
305 	    memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
306 		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
307 		       (u64)phys_initrd_start, phys_initrd_size);
308 		phys_initrd_start = phys_initrd_size = 0;
309 	}
310 	if (phys_initrd_size) {
311 		memblock_reserve(phys_initrd_start, phys_initrd_size);
312 
313 		/* Now convert initrd to virtual addresses */
314 		initrd_start = __phys_to_virt(phys_initrd_start);
315 		initrd_end = initrd_start + phys_initrd_size;
316 	}
317 #endif
318 
319 	arm_mm_memblock_reserve();
320 	arm_dt_memblock_reserve();
321 
322 	/* reserve any platform specific memblock areas */
323 	if (mdesc->reserve)
324 		mdesc->reserve();
325 
326 	/*
327 	 * reserve memory for DMA contigouos allocations,
328 	 * must come from DMA area inside low memory
329 	 */
330 	dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit));
331 
332 	arm_memblock_steal_permitted = false;
333 	memblock_dump_all();
334 }
335 
336 void __init bootmem_init(void)
337 {
338 	unsigned long min, max_low, max_high;
339 
340 	memblock_allow_resize();
341 	max_low = max_high = 0;
342 
343 	find_limits(&min, &max_low, &max_high);
344 
345 	/*
346 	 * Sparsemem tries to allocate bootmem in memory_present(),
347 	 * so must be done after the fixed reservations
348 	 */
349 	arm_memory_present();
350 
351 	/*
352 	 * sparse_init() needs the bootmem allocator up and running.
353 	 */
354 	sparse_init();
355 
356 	/*
357 	 * Now free the memory - free_area_init_node needs
358 	 * the sparse mem_map arrays initialized by sparse_init()
359 	 * for memmap_init_zone(), otherwise all PFNs are invalid.
360 	 */
361 	zone_sizes_init(min, max_low, max_high);
362 
363 	/*
364 	 * This doesn't seem to be used by the Linux memory manager any
365 	 * more, but is used by ll_rw_block.  If we can get rid of it, we
366 	 * also get rid of some of the stuff above as well.
367 	 */
368 	min_low_pfn = min;
369 	max_low_pfn = max_low;
370 	max_pfn = max_high;
371 }
372 
373 /*
374  * Poison init memory with an undefined instruction (ARM) or a branch to an
375  * undefined instruction (Thumb).
376  */
377 static inline void poison_init_mem(void *s, size_t count)
378 {
379 	u32 *p = (u32 *)s;
380 	for (; count != 0; count -= 4)
381 		*p++ = 0xe7fddef0;
382 }
383 
384 static inline void
385 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
386 {
387 	struct page *start_pg, *end_pg;
388 	phys_addr_t pg, pgend;
389 
390 	/*
391 	 * Convert start_pfn/end_pfn to a struct page pointer.
392 	 */
393 	start_pg = pfn_to_page(start_pfn - 1) + 1;
394 	end_pg = pfn_to_page(end_pfn - 1) + 1;
395 
396 	/*
397 	 * Convert to physical addresses, and
398 	 * round start upwards and end downwards.
399 	 */
400 	pg = PAGE_ALIGN(__pa(start_pg));
401 	pgend = __pa(end_pg) & PAGE_MASK;
402 
403 	/*
404 	 * If there are free pages between these,
405 	 * free the section of the memmap array.
406 	 */
407 	if (pg < pgend)
408 		memblock_free_early(pg, pgend - pg);
409 }
410 
411 /*
412  * The mem_map array can get very big.  Free the unused area of the memory map.
413  */
414 static void __init free_unused_memmap(struct meminfo *mi)
415 {
416 	unsigned long bank_start, prev_bank_end = 0;
417 	unsigned int i;
418 
419 	/*
420 	 * This relies on each bank being in address order.
421 	 * The banks are sorted previously in bootmem_init().
422 	 */
423 	for_each_bank(i, mi) {
424 		struct membank *bank = &mi->bank[i];
425 
426 		bank_start = bank_pfn_start(bank);
427 
428 #ifdef CONFIG_SPARSEMEM
429 		/*
430 		 * Take care not to free memmap entries that don't exist
431 		 * due to SPARSEMEM sections which aren't present.
432 		 */
433 		bank_start = min(bank_start,
434 				 ALIGN(prev_bank_end, PAGES_PER_SECTION));
435 #else
436 		/*
437 		 * Align down here since the VM subsystem insists that the
438 		 * memmap entries are valid from the bank start aligned to
439 		 * MAX_ORDER_NR_PAGES.
440 		 */
441 		bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
442 #endif
443 		/*
444 		 * If we had a previous bank, and there is a space
445 		 * between the current bank and the previous, free it.
446 		 */
447 		if (prev_bank_end && prev_bank_end < bank_start)
448 			free_memmap(prev_bank_end, bank_start);
449 
450 		/*
451 		 * Align up here since the VM subsystem insists that the
452 		 * memmap entries are valid from the bank end aligned to
453 		 * MAX_ORDER_NR_PAGES.
454 		 */
455 		prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
456 	}
457 
458 #ifdef CONFIG_SPARSEMEM
459 	if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
460 		free_memmap(prev_bank_end,
461 			    ALIGN(prev_bank_end, PAGES_PER_SECTION));
462 #endif
463 }
464 
465 #ifdef CONFIG_HIGHMEM
466 static inline void free_area_high(unsigned long pfn, unsigned long end)
467 {
468 	for (; pfn < end; pfn++)
469 		free_highmem_page(pfn_to_page(pfn));
470 }
471 #endif
472 
473 static void __init free_highpages(void)
474 {
475 #ifdef CONFIG_HIGHMEM
476 	unsigned long max_low = max_low_pfn;
477 	struct memblock_region *mem, *res;
478 
479 	/* set highmem page free */
480 	for_each_memblock(memory, mem) {
481 		unsigned long start = memblock_region_memory_base_pfn(mem);
482 		unsigned long end = memblock_region_memory_end_pfn(mem);
483 
484 		/* Ignore complete lowmem entries */
485 		if (end <= max_low)
486 			continue;
487 
488 		/* Truncate partial highmem entries */
489 		if (start < max_low)
490 			start = max_low;
491 
492 		/* Find and exclude any reserved regions */
493 		for_each_memblock(reserved, res) {
494 			unsigned long res_start, res_end;
495 
496 			res_start = memblock_region_reserved_base_pfn(res);
497 			res_end = memblock_region_reserved_end_pfn(res);
498 
499 			if (res_end < start)
500 				continue;
501 			if (res_start < start)
502 				res_start = start;
503 			if (res_start > end)
504 				res_start = end;
505 			if (res_end > end)
506 				res_end = end;
507 			if (res_start != start)
508 				free_area_high(start, res_start);
509 			start = res_end;
510 			if (start == end)
511 				break;
512 		}
513 
514 		/* And now free anything which remains */
515 		if (start < end)
516 			free_area_high(start, end);
517 	}
518 #endif
519 }
520 
521 /*
522  * mem_init() marks the free areas in the mem_map and tells us how much
523  * memory is free.  This is done after various parts of the system have
524  * claimed their memory after the kernel image.
525  */
526 void __init mem_init(void)
527 {
528 #ifdef CONFIG_HAVE_TCM
529 	/* These pointers are filled in on TCM detection */
530 	extern u32 dtcm_end;
531 	extern u32 itcm_end;
532 #endif
533 
534 	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
535 
536 	/* this will put all unused low memory onto the freelists */
537 	free_unused_memmap(&meminfo);
538 	free_all_bootmem();
539 
540 #ifdef CONFIG_SA1111
541 	/* now that our DMA memory is actually so designated, we can free it */
542 	free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
543 #endif
544 
545 	free_highpages();
546 
547 	mem_init_print_info(NULL);
548 
549 #define MLK(b, t) b, t, ((t) - (b)) >> 10
550 #define MLM(b, t) b, t, ((t) - (b)) >> 20
551 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
552 
553 	printk(KERN_NOTICE "Virtual kernel memory layout:\n"
554 			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
555 #ifdef CONFIG_HAVE_TCM
556 			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
557 			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
558 #endif
559 			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
560 			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
561 			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
562 #ifdef CONFIG_HIGHMEM
563 			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
564 #endif
565 #ifdef CONFIG_MODULES
566 			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
567 #endif
568 			"      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
569 			"      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
570 			"      .data : 0x%p" " - 0x%p" "   (%4d kB)\n"
571 			"       .bss : 0x%p" " - 0x%p" "   (%4d kB)\n",
572 
573 			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
574 				(PAGE_SIZE)),
575 #ifdef CONFIG_HAVE_TCM
576 			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
577 			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
578 #endif
579 			MLK(FIXADDR_START, FIXADDR_TOP),
580 			MLM(VMALLOC_START, VMALLOC_END),
581 			MLM(PAGE_OFFSET, (unsigned long)high_memory),
582 #ifdef CONFIG_HIGHMEM
583 			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
584 				(PAGE_SIZE)),
585 #endif
586 #ifdef CONFIG_MODULES
587 			MLM(MODULES_VADDR, MODULES_END),
588 #endif
589 
590 			MLK_ROUNDUP(_text, _etext),
591 			MLK_ROUNDUP(__init_begin, __init_end),
592 			MLK_ROUNDUP(_sdata, _edata),
593 			MLK_ROUNDUP(__bss_start, __bss_stop));
594 
595 #undef MLK
596 #undef MLM
597 #undef MLK_ROUNDUP
598 
599 	/*
600 	 * Check boundaries twice: Some fundamental inconsistencies can
601 	 * be detected at build time already.
602 	 */
603 #ifdef CONFIG_MMU
604 	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
605 	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
606 #endif
607 
608 #ifdef CONFIG_HIGHMEM
609 	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
610 	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
611 #endif
612 
613 	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
614 		extern int sysctl_overcommit_memory;
615 		/*
616 		 * On a machine this small we won't get
617 		 * anywhere without overcommit, so turn
618 		 * it on by default.
619 		 */
620 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
621 	}
622 }
623 
624 void free_initmem(void)
625 {
626 #ifdef CONFIG_HAVE_TCM
627 	extern char __tcm_start, __tcm_end;
628 
629 	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
630 	free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
631 #endif
632 
633 	poison_init_mem(__init_begin, __init_end - __init_begin);
634 	if (!machine_is_integrator() && !machine_is_cintegrator())
635 		free_initmem_default(-1);
636 }
637 
638 #ifdef CONFIG_BLK_DEV_INITRD
639 
640 static int keep_initrd;
641 
642 void free_initrd_mem(unsigned long start, unsigned long end)
643 {
644 	if (!keep_initrd) {
645 		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
646 		free_reserved_area((void *)start, (void *)end, -1, "initrd");
647 	}
648 }
649 
650 static int __init keepinitrd_setup(char *__unused)
651 {
652 	keep_initrd = 1;
653 	return 1;
654 }
655 
656 __setup("keepinitrd", keepinitrd_setup);
657 #endif
658