xref: /openbmc/linux/arch/arm/mm/init.c (revision 6774def6)
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/cp15.h>
27 #include <asm/mach-types.h>
28 #include <asm/memblock.h>
29 #include <asm/prom.h>
30 #include <asm/sections.h>
31 #include <asm/setup.h>
32 #include <asm/tlb.h>
33 #include <asm/fixmap.h>
34 
35 #include <asm/mach/arch.h>
36 #include <asm/mach/map.h>
37 
38 #include "mm.h"
39 
40 #ifdef CONFIG_CPU_CP15_MMU
41 unsigned long __init __clear_cr(unsigned long mask)
42 {
43 	cr_alignment = cr_alignment & ~mask;
44 	return cr_alignment;
45 }
46 #endif
47 
48 static phys_addr_t phys_initrd_start __initdata = 0;
49 static unsigned long phys_initrd_size __initdata = 0;
50 
51 static int __init early_initrd(char *p)
52 {
53 	phys_addr_t start;
54 	unsigned long size;
55 	char *endp;
56 
57 	start = memparse(p, &endp);
58 	if (*endp == ',') {
59 		size = memparse(endp + 1, NULL);
60 
61 		phys_initrd_start = start;
62 		phys_initrd_size = size;
63 	}
64 	return 0;
65 }
66 early_param("initrd", early_initrd);
67 
68 static int __init parse_tag_initrd(const struct tag *tag)
69 {
70 	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
71 		"please update your bootloader.\n");
72 	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
73 	phys_initrd_size = tag->u.initrd.size;
74 	return 0;
75 }
76 
77 __tagtable(ATAG_INITRD, parse_tag_initrd);
78 
79 static int __init parse_tag_initrd2(const struct tag *tag)
80 {
81 	phys_initrd_start = tag->u.initrd.start;
82 	phys_initrd_size = tag->u.initrd.size;
83 	return 0;
84 }
85 
86 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
87 
88 /*
89  * This keeps memory configuration data used by a couple memory
90  * initialization functions, as well as show_mem() for the skipping
91  * of holes in the memory map.  It is populated by arm_add_memory().
92  */
93 void show_mem(unsigned int filter)
94 {
95 	int free = 0, total = 0, reserved = 0;
96 	int shared = 0, cached = 0, slab = 0;
97 	struct memblock_region *reg;
98 
99 	printk("Mem-info:\n");
100 	show_free_areas(filter);
101 
102 	for_each_memblock (memory, reg) {
103 		unsigned int pfn1, pfn2;
104 		struct page *page, *end;
105 
106 		pfn1 = memblock_region_memory_base_pfn(reg);
107 		pfn2 = memblock_region_memory_end_pfn(reg);
108 
109 		page = pfn_to_page(pfn1);
110 		end  = pfn_to_page(pfn2 - 1) + 1;
111 
112 		do {
113 			total++;
114 			if (PageReserved(page))
115 				reserved++;
116 			else if (PageSwapCache(page))
117 				cached++;
118 			else if (PageSlab(page))
119 				slab++;
120 			else if (!page_count(page))
121 				free++;
122 			else
123 				shared += page_count(page) - 1;
124 			pfn1++;
125 			page = pfn_to_page(pfn1);
126 		} while (pfn1 < pfn2);
127 	}
128 
129 	printk("%d pages of RAM\n", total);
130 	printk("%d free pages\n", free);
131 	printk("%d reserved pages\n", reserved);
132 	printk("%d slab pages\n", slab);
133 	printk("%d pages shared\n", shared);
134 	printk("%d pages swap cached\n", cached);
135 }
136 
137 static void __init find_limits(unsigned long *min, unsigned long *max_low,
138 			       unsigned long *max_high)
139 {
140 	*max_low = PFN_DOWN(memblock_get_current_limit());
141 	*min = PFN_UP(memblock_start_of_DRAM());
142 	*max_high = PFN_DOWN(memblock_end_of_DRAM());
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(const struct machine_desc *mdesc)
278 {
279 	/* Register the kernel text, kernel data and initrd with memblock. */
280 #ifdef CONFIG_XIP_KERNEL
281 	memblock_reserve(__pa(_sdata), _end - _sdata);
282 #else
283 	memblock_reserve(__pa(_stext), _end - _stext);
284 #endif
285 #ifdef CONFIG_BLK_DEV_INITRD
286 	/* FDT scan will populate initrd_start */
287 	if (initrd_start && !phys_initrd_size) {
288 		phys_initrd_start = __virt_to_phys(initrd_start);
289 		phys_initrd_size = initrd_end - initrd_start;
290 	}
291 	initrd_start = initrd_end = 0;
292 	if (phys_initrd_size &&
293 	    !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
294 		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
295 		       (u64)phys_initrd_start, phys_initrd_size);
296 		phys_initrd_start = phys_initrd_size = 0;
297 	}
298 	if (phys_initrd_size &&
299 	    memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
300 		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use 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_reserve(phys_initrd_start, phys_initrd_size);
306 
307 		/* Now convert initrd to virtual addresses */
308 		initrd_start = __phys_to_virt(phys_initrd_start);
309 		initrd_end = initrd_start + phys_initrd_size;
310 	}
311 #endif
312 
313 	arm_mm_memblock_reserve();
314 
315 	/* reserve any platform specific memblock areas */
316 	if (mdesc->reserve)
317 		mdesc->reserve();
318 
319 	early_init_fdt_scan_reserved_mem();
320 
321 	/*
322 	 * reserve memory for DMA contigouos allocations,
323 	 * must come from DMA area inside low memory
324 	 */
325 	dma_contiguous_reserve(arm_dma_limit);
326 
327 	arm_memblock_steal_permitted = false;
328 	memblock_dump_all();
329 }
330 
331 void __init bootmem_init(void)
332 {
333 	unsigned long min, max_low, max_high;
334 
335 	memblock_allow_resize();
336 	max_low = max_high = 0;
337 
338 	find_limits(&min, &max_low, &max_high);
339 
340 	/*
341 	 * Sparsemem tries to allocate bootmem in memory_present(),
342 	 * so must be done after the fixed reservations
343 	 */
344 	arm_memory_present();
345 
346 	/*
347 	 * sparse_init() needs the bootmem allocator up and running.
348 	 */
349 	sparse_init();
350 
351 	/*
352 	 * Now free the memory - free_area_init_node needs
353 	 * the sparse mem_map arrays initialized by sparse_init()
354 	 * for memmap_init_zone(), otherwise all PFNs are invalid.
355 	 */
356 	zone_sizes_init(min, max_low, max_high);
357 
358 	/*
359 	 * This doesn't seem to be used by the Linux memory manager any
360 	 * more, but is used by ll_rw_block.  If we can get rid of it, we
361 	 * also get rid of some of the stuff above as well.
362 	 */
363 	min_low_pfn = min;
364 	max_low_pfn = max_low;
365 	max_pfn = max_high;
366 }
367 
368 /*
369  * Poison init memory with an undefined instruction (ARM) or a branch to an
370  * undefined instruction (Thumb).
371  */
372 static inline void poison_init_mem(void *s, size_t count)
373 {
374 	u32 *p = (u32 *)s;
375 	for (; count != 0; count -= 4)
376 		*p++ = 0xe7fddef0;
377 }
378 
379 static inline void
380 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
381 {
382 	struct page *start_pg, *end_pg;
383 	phys_addr_t pg, pgend;
384 
385 	/*
386 	 * Convert start_pfn/end_pfn to a struct page pointer.
387 	 */
388 	start_pg = pfn_to_page(start_pfn - 1) + 1;
389 	end_pg = pfn_to_page(end_pfn - 1) + 1;
390 
391 	/*
392 	 * Convert to physical addresses, and
393 	 * round start upwards and end downwards.
394 	 */
395 	pg = PAGE_ALIGN(__pa(start_pg));
396 	pgend = __pa(end_pg) & PAGE_MASK;
397 
398 	/*
399 	 * If there are free pages between these,
400 	 * free the section of the memmap array.
401 	 */
402 	if (pg < pgend)
403 		memblock_free_early(pg, pgend - pg);
404 }
405 
406 /*
407  * The mem_map array can get very big.  Free the unused area of the memory map.
408  */
409 static void __init free_unused_memmap(void)
410 {
411 	unsigned long start, prev_end = 0;
412 	struct memblock_region *reg;
413 
414 	/*
415 	 * This relies on each bank being in address order.
416 	 * The banks are sorted previously in bootmem_init().
417 	 */
418 	for_each_memblock(memory, reg) {
419 		start = memblock_region_memory_base_pfn(reg);
420 
421 #ifdef CONFIG_SPARSEMEM
422 		/*
423 		 * Take care not to free memmap entries that don't exist
424 		 * due to SPARSEMEM sections which aren't present.
425 		 */
426 		start = min(start,
427 				 ALIGN(prev_end, PAGES_PER_SECTION));
428 #else
429 		/*
430 		 * Align down here since the VM subsystem insists that the
431 		 * memmap entries are valid from the bank start aligned to
432 		 * MAX_ORDER_NR_PAGES.
433 		 */
434 		start = round_down(start, MAX_ORDER_NR_PAGES);
435 #endif
436 		/*
437 		 * If we had a previous bank, and there is a space
438 		 * between the current bank and the previous, free it.
439 		 */
440 		if (prev_end && prev_end < start)
441 			free_memmap(prev_end, start);
442 
443 		/*
444 		 * Align up here since the VM subsystem insists that the
445 		 * memmap entries are valid from the bank end aligned to
446 		 * MAX_ORDER_NR_PAGES.
447 		 */
448 		prev_end = ALIGN(memblock_region_memory_end_pfn(reg),
449 				 MAX_ORDER_NR_PAGES);
450 	}
451 
452 #ifdef CONFIG_SPARSEMEM
453 	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
454 		free_memmap(prev_end,
455 			    ALIGN(prev_end, PAGES_PER_SECTION));
456 #endif
457 }
458 
459 #ifdef CONFIG_HIGHMEM
460 static inline void free_area_high(unsigned long pfn, unsigned long end)
461 {
462 	for (; pfn < end; pfn++)
463 		free_highmem_page(pfn_to_page(pfn));
464 }
465 #endif
466 
467 static void __init free_highpages(void)
468 {
469 #ifdef CONFIG_HIGHMEM
470 	unsigned long max_low = max_low_pfn;
471 	struct memblock_region *mem, *res;
472 
473 	/* set highmem page free */
474 	for_each_memblock(memory, mem) {
475 		unsigned long start = memblock_region_memory_base_pfn(mem);
476 		unsigned long end = memblock_region_memory_end_pfn(mem);
477 
478 		/* Ignore complete lowmem entries */
479 		if (end <= max_low)
480 			continue;
481 
482 		/* Truncate partial highmem entries */
483 		if (start < max_low)
484 			start = max_low;
485 
486 		/* Find and exclude any reserved regions */
487 		for_each_memblock(reserved, res) {
488 			unsigned long res_start, res_end;
489 
490 			res_start = memblock_region_reserved_base_pfn(res);
491 			res_end = memblock_region_reserved_end_pfn(res);
492 
493 			if (res_end < start)
494 				continue;
495 			if (res_start < start)
496 				res_start = start;
497 			if (res_start > end)
498 				res_start = end;
499 			if (res_end > end)
500 				res_end = end;
501 			if (res_start != start)
502 				free_area_high(start, res_start);
503 			start = res_end;
504 			if (start == end)
505 				break;
506 		}
507 
508 		/* And now free anything which remains */
509 		if (start < end)
510 			free_area_high(start, end);
511 	}
512 #endif
513 }
514 
515 /*
516  * mem_init() marks the free areas in the mem_map and tells us how much
517  * memory is free.  This is done after various parts of the system have
518  * claimed their memory after the kernel image.
519  */
520 void __init mem_init(void)
521 {
522 #ifdef CONFIG_HAVE_TCM
523 	/* These pointers are filled in on TCM detection */
524 	extern u32 dtcm_end;
525 	extern u32 itcm_end;
526 #endif
527 
528 	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
529 
530 	/* this will put all unused low memory onto the freelists */
531 	free_unused_memmap();
532 	free_all_bootmem();
533 
534 #ifdef CONFIG_SA1111
535 	/* now that our DMA memory is actually so designated, we can free it */
536 	free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
537 #endif
538 
539 	free_highpages();
540 
541 	mem_init_print_info(NULL);
542 
543 #define MLK(b, t) b, t, ((t) - (b)) >> 10
544 #define MLM(b, t) b, t, ((t) - (b)) >> 20
545 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
546 
547 	printk(KERN_NOTICE "Virtual kernel memory layout:\n"
548 			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
549 #ifdef CONFIG_HAVE_TCM
550 			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
551 			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
552 #endif
553 			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
554 			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
555 			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
556 #ifdef CONFIG_HIGHMEM
557 			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
558 #endif
559 #ifdef CONFIG_MODULES
560 			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
561 #endif
562 			"      .text : 0x%p" " - 0x%p" "   (%4td kB)\n"
563 			"      .init : 0x%p" " - 0x%p" "   (%4td kB)\n"
564 			"      .data : 0x%p" " - 0x%p" "   (%4td kB)\n"
565 			"       .bss : 0x%p" " - 0x%p" "   (%4td kB)\n",
566 
567 			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
568 				(PAGE_SIZE)),
569 #ifdef CONFIG_HAVE_TCM
570 			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
571 			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
572 #endif
573 			MLK(FIXADDR_START, FIXADDR_TOP),
574 			MLM(VMALLOC_START, VMALLOC_END),
575 			MLM(PAGE_OFFSET, (unsigned long)high_memory),
576 #ifdef CONFIG_HIGHMEM
577 			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
578 				(PAGE_SIZE)),
579 #endif
580 #ifdef CONFIG_MODULES
581 			MLM(MODULES_VADDR, MODULES_END),
582 #endif
583 
584 			MLK_ROUNDUP(_text, _etext),
585 			MLK_ROUNDUP(__init_begin, __init_end),
586 			MLK_ROUNDUP(_sdata, _edata),
587 			MLK_ROUNDUP(__bss_start, __bss_stop));
588 
589 #undef MLK
590 #undef MLM
591 #undef MLK_ROUNDUP
592 
593 	/*
594 	 * Check boundaries twice: Some fundamental inconsistencies can
595 	 * be detected at build time already.
596 	 */
597 #ifdef CONFIG_MMU
598 	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
599 	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
600 #endif
601 
602 #ifdef CONFIG_HIGHMEM
603 	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
604 	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
605 #endif
606 
607 	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
608 		extern int sysctl_overcommit_memory;
609 		/*
610 		 * On a machine this small we won't get
611 		 * anywhere without overcommit, so turn
612 		 * it on by default.
613 		 */
614 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
615 	}
616 }
617 
618 void free_initmem(void)
619 {
620 #ifdef CONFIG_HAVE_TCM
621 	extern char __tcm_start, __tcm_end;
622 
623 	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
624 	free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
625 #endif
626 
627 	poison_init_mem(__init_begin, __init_end - __init_begin);
628 	if (!machine_is_integrator() && !machine_is_cintegrator())
629 		free_initmem_default(-1);
630 }
631 
632 #ifdef CONFIG_BLK_DEV_INITRD
633 
634 static int keep_initrd;
635 
636 void free_initrd_mem(unsigned long start, unsigned long end)
637 {
638 	if (!keep_initrd) {
639 		if (start == initrd_start)
640 			start = round_down(start, PAGE_SIZE);
641 		if (end == initrd_end)
642 			end = round_up(end, PAGE_SIZE);
643 
644 		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
645 		free_reserved_area((void *)start, (void *)end, -1, "initrd");
646 	}
647 }
648 
649 static int __init keepinitrd_setup(char *__unused)
650 {
651 	keep_initrd = 1;
652 	return 1;
653 }
654 
655 __setup("keepinitrd", keepinitrd_setup);
656 #endif
657