xref: /openbmc/linux/arch/arm/mm/init.c (revision ca55b2fe)
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/system_info.h>
33 #include <asm/tlb.h>
34 #include <asm/fixmap.h>
35 
36 #include <asm/mach/arch.h>
37 #include <asm/mach/map.h>
38 
39 #include "mm.h"
40 
41 #ifdef CONFIG_CPU_CP15_MMU
42 unsigned long __init __clear_cr(unsigned long mask)
43 {
44 	cr_alignment = cr_alignment & ~mask;
45 	return cr_alignment;
46 }
47 #endif
48 
49 static phys_addr_t phys_initrd_start __initdata = 0;
50 static unsigned long phys_initrd_size __initdata = 0;
51 
52 static int __init early_initrd(char *p)
53 {
54 	phys_addr_t start;
55 	unsigned long size;
56 	char *endp;
57 
58 	start = memparse(p, &endp);
59 	if (*endp == ',') {
60 		size = memparse(endp + 1, NULL);
61 
62 		phys_initrd_start = start;
63 		phys_initrd_size = size;
64 	}
65 	return 0;
66 }
67 early_param("initrd", early_initrd);
68 
69 static int __init parse_tag_initrd(const struct tag *tag)
70 {
71 	pr_warn("ATAG_INITRD is deprecated; "
72 		"please update your bootloader.\n");
73 	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
74 	phys_initrd_size = tag->u.initrd.size;
75 	return 0;
76 }
77 
78 __tagtable(ATAG_INITRD, parse_tag_initrd);
79 
80 static int __init parse_tag_initrd2(const struct tag *tag)
81 {
82 	phys_initrd_start = tag->u.initrd.start;
83 	phys_initrd_size = tag->u.initrd.size;
84 	return 0;
85 }
86 
87 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
88 
89 static void __init find_limits(unsigned long *min, unsigned long *max_low,
90 			       unsigned long *max_high)
91 {
92 	*max_low = PFN_DOWN(memblock_get_current_limit());
93 	*min = PFN_UP(memblock_start_of_DRAM());
94 	*max_high = PFN_DOWN(memblock_end_of_DRAM());
95 }
96 
97 #ifdef CONFIG_ZONE_DMA
98 
99 phys_addr_t arm_dma_zone_size __read_mostly;
100 EXPORT_SYMBOL(arm_dma_zone_size);
101 
102 /*
103  * The DMA mask corresponding to the maximum bus address allocatable
104  * using GFP_DMA.  The default here places no restriction on DMA
105  * allocations.  This must be the smallest DMA mask in the system,
106  * so a successful GFP_DMA allocation will always satisfy this.
107  */
108 phys_addr_t arm_dma_limit;
109 unsigned long arm_dma_pfn_limit;
110 
111 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
112 	unsigned long dma_size)
113 {
114 	if (size[0] <= dma_size)
115 		return;
116 
117 	size[ZONE_NORMAL] = size[0] - dma_size;
118 	size[ZONE_DMA] = dma_size;
119 	hole[ZONE_NORMAL] = hole[0];
120 	hole[ZONE_DMA] = 0;
121 }
122 #endif
123 
124 void __init setup_dma_zone(const struct machine_desc *mdesc)
125 {
126 #ifdef CONFIG_ZONE_DMA
127 	if (mdesc->dma_zone_size) {
128 		arm_dma_zone_size = mdesc->dma_zone_size;
129 		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
130 	} else
131 		arm_dma_limit = 0xffffffff;
132 	arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
133 #endif
134 }
135 
136 static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
137 	unsigned long max_high)
138 {
139 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
140 	struct memblock_region *reg;
141 
142 	/*
143 	 * initialise the zones.
144 	 */
145 	memset(zone_size, 0, sizeof(zone_size));
146 
147 	/*
148 	 * The memory size has already been determined.  If we need
149 	 * to do anything fancy with the allocation of this memory
150 	 * to the zones, now is the time to do it.
151 	 */
152 	zone_size[0] = max_low - min;
153 #ifdef CONFIG_HIGHMEM
154 	zone_size[ZONE_HIGHMEM] = max_high - max_low;
155 #endif
156 
157 	/*
158 	 * Calculate the size of the holes.
159 	 *  holes = node_size - sum(bank_sizes)
160 	 */
161 	memcpy(zhole_size, zone_size, sizeof(zhole_size));
162 	for_each_memblock(memory, reg) {
163 		unsigned long start = memblock_region_memory_base_pfn(reg);
164 		unsigned long end = memblock_region_memory_end_pfn(reg);
165 
166 		if (start < max_low) {
167 			unsigned long low_end = min(end, max_low);
168 			zhole_size[0] -= low_end - start;
169 		}
170 #ifdef CONFIG_HIGHMEM
171 		if (end > max_low) {
172 			unsigned long high_start = max(start, max_low);
173 			zhole_size[ZONE_HIGHMEM] -= end - high_start;
174 		}
175 #endif
176 	}
177 
178 #ifdef CONFIG_ZONE_DMA
179 	/*
180 	 * Adjust the sizes according to any special requirements for
181 	 * this machine type.
182 	 */
183 	if (arm_dma_zone_size)
184 		arm_adjust_dma_zone(zone_size, zhole_size,
185 			arm_dma_zone_size >> PAGE_SHIFT);
186 #endif
187 
188 	free_area_init_node(0, zone_size, min, zhole_size);
189 }
190 
191 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
192 int pfn_valid(unsigned long pfn)
193 {
194 	return memblock_is_memory(__pfn_to_phys(pfn));
195 }
196 EXPORT_SYMBOL(pfn_valid);
197 #endif
198 
199 #ifndef CONFIG_SPARSEMEM
200 static void __init arm_memory_present(void)
201 {
202 }
203 #else
204 static void __init arm_memory_present(void)
205 {
206 	struct memblock_region *reg;
207 
208 	for_each_memblock(memory, reg)
209 		memory_present(0, memblock_region_memory_base_pfn(reg),
210 			       memblock_region_memory_end_pfn(reg));
211 }
212 #endif
213 
214 static bool arm_memblock_steal_permitted = true;
215 
216 phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
217 {
218 	phys_addr_t phys;
219 
220 	BUG_ON(!arm_memblock_steal_permitted);
221 
222 	phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
223 	memblock_free(phys, size);
224 	memblock_remove(phys, size);
225 
226 	return phys;
227 }
228 
229 void __init arm_memblock_init(const struct machine_desc *mdesc)
230 {
231 	/* Register the kernel text, kernel data and initrd with memblock. */
232 #ifdef CONFIG_XIP_KERNEL
233 	memblock_reserve(__pa(_sdata), _end - _sdata);
234 #else
235 	memblock_reserve(__pa(_stext), _end - _stext);
236 #endif
237 #ifdef CONFIG_BLK_DEV_INITRD
238 	/* FDT scan will populate initrd_start */
239 	if (initrd_start && !phys_initrd_size) {
240 		phys_initrd_start = __virt_to_phys(initrd_start);
241 		phys_initrd_size = initrd_end - initrd_start;
242 	}
243 	initrd_start = initrd_end = 0;
244 	if (phys_initrd_size &&
245 	    !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
246 		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
247 		       (u64)phys_initrd_start, phys_initrd_size);
248 		phys_initrd_start = phys_initrd_size = 0;
249 	}
250 	if (phys_initrd_size &&
251 	    memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
252 		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
253 		       (u64)phys_initrd_start, phys_initrd_size);
254 		phys_initrd_start = phys_initrd_size = 0;
255 	}
256 	if (phys_initrd_size) {
257 		memblock_reserve(phys_initrd_start, phys_initrd_size);
258 
259 		/* Now convert initrd to virtual addresses */
260 		initrd_start = __phys_to_virt(phys_initrd_start);
261 		initrd_end = initrd_start + phys_initrd_size;
262 	}
263 #endif
264 
265 	arm_mm_memblock_reserve();
266 
267 	/* reserve any platform specific memblock areas */
268 	if (mdesc->reserve)
269 		mdesc->reserve();
270 
271 	early_init_fdt_reserve_self();
272 	early_init_fdt_scan_reserved_mem();
273 
274 	/* reserve memory for DMA contiguous allocations */
275 	dma_contiguous_reserve(arm_dma_limit);
276 
277 	arm_memblock_steal_permitted = false;
278 	memblock_dump_all();
279 }
280 
281 void __init bootmem_init(void)
282 {
283 	unsigned long min, max_low, max_high;
284 
285 	memblock_allow_resize();
286 	max_low = max_high = 0;
287 
288 	find_limits(&min, &max_low, &max_high);
289 
290 	early_memtest((phys_addr_t)min << PAGE_SHIFT,
291 		      (phys_addr_t)max_low << PAGE_SHIFT);
292 
293 	/*
294 	 * Sparsemem tries to allocate bootmem in memory_present(),
295 	 * so must be done after the fixed reservations
296 	 */
297 	arm_memory_present();
298 
299 	/*
300 	 * sparse_init() needs the bootmem allocator up and running.
301 	 */
302 	sparse_init();
303 
304 	/*
305 	 * Now free the memory - free_area_init_node needs
306 	 * the sparse mem_map arrays initialized by sparse_init()
307 	 * for memmap_init_zone(), otherwise all PFNs are invalid.
308 	 */
309 	zone_sizes_init(min, max_low, max_high);
310 
311 	/*
312 	 * This doesn't seem to be used by the Linux memory manager any
313 	 * more, but is used by ll_rw_block.  If we can get rid of it, we
314 	 * also get rid of some of the stuff above as well.
315 	 */
316 	min_low_pfn = min;
317 	max_low_pfn = max_low;
318 	max_pfn = max_high;
319 }
320 
321 /*
322  * Poison init memory with an undefined instruction (ARM) or a branch to an
323  * undefined instruction (Thumb).
324  */
325 static inline void poison_init_mem(void *s, size_t count)
326 {
327 	u32 *p = (u32 *)s;
328 	for (; count != 0; count -= 4)
329 		*p++ = 0xe7fddef0;
330 }
331 
332 static inline void
333 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
334 {
335 	struct page *start_pg, *end_pg;
336 	phys_addr_t pg, pgend;
337 
338 	/*
339 	 * Convert start_pfn/end_pfn to a struct page pointer.
340 	 */
341 	start_pg = pfn_to_page(start_pfn - 1) + 1;
342 	end_pg = pfn_to_page(end_pfn - 1) + 1;
343 
344 	/*
345 	 * Convert to physical addresses, and
346 	 * round start upwards and end downwards.
347 	 */
348 	pg = PAGE_ALIGN(__pa(start_pg));
349 	pgend = __pa(end_pg) & PAGE_MASK;
350 
351 	/*
352 	 * If there are free pages between these,
353 	 * free the section of the memmap array.
354 	 */
355 	if (pg < pgend)
356 		memblock_free_early(pg, pgend - pg);
357 }
358 
359 /*
360  * The mem_map array can get very big.  Free the unused area of the memory map.
361  */
362 static void __init free_unused_memmap(void)
363 {
364 	unsigned long start, prev_end = 0;
365 	struct memblock_region *reg;
366 
367 	/*
368 	 * This relies on each bank being in address order.
369 	 * The banks are sorted previously in bootmem_init().
370 	 */
371 	for_each_memblock(memory, reg) {
372 		start = memblock_region_memory_base_pfn(reg);
373 
374 #ifdef CONFIG_SPARSEMEM
375 		/*
376 		 * Take care not to free memmap entries that don't exist
377 		 * due to SPARSEMEM sections which aren't present.
378 		 */
379 		start = min(start,
380 				 ALIGN(prev_end, PAGES_PER_SECTION));
381 #else
382 		/*
383 		 * Align down here since the VM subsystem insists that the
384 		 * memmap entries are valid from the bank start aligned to
385 		 * MAX_ORDER_NR_PAGES.
386 		 */
387 		start = round_down(start, MAX_ORDER_NR_PAGES);
388 #endif
389 		/*
390 		 * If we had a previous bank, and there is a space
391 		 * between the current bank and the previous, free it.
392 		 */
393 		if (prev_end && prev_end < start)
394 			free_memmap(prev_end, start);
395 
396 		/*
397 		 * Align up here since the VM subsystem insists that the
398 		 * memmap entries are valid from the bank end aligned to
399 		 * MAX_ORDER_NR_PAGES.
400 		 */
401 		prev_end = ALIGN(memblock_region_memory_end_pfn(reg),
402 				 MAX_ORDER_NR_PAGES);
403 	}
404 
405 #ifdef CONFIG_SPARSEMEM
406 	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
407 		free_memmap(prev_end,
408 			    ALIGN(prev_end, PAGES_PER_SECTION));
409 #endif
410 }
411 
412 #ifdef CONFIG_HIGHMEM
413 static inline void free_area_high(unsigned long pfn, unsigned long end)
414 {
415 	for (; pfn < end; pfn++)
416 		free_highmem_page(pfn_to_page(pfn));
417 }
418 #endif
419 
420 static void __init free_highpages(void)
421 {
422 #ifdef CONFIG_HIGHMEM
423 	unsigned long max_low = max_low_pfn;
424 	struct memblock_region *mem, *res;
425 
426 	/* set highmem page free */
427 	for_each_memblock(memory, mem) {
428 		unsigned long start = memblock_region_memory_base_pfn(mem);
429 		unsigned long end = memblock_region_memory_end_pfn(mem);
430 
431 		/* Ignore complete lowmem entries */
432 		if (end <= max_low)
433 			continue;
434 
435 		/* Truncate partial highmem entries */
436 		if (start < max_low)
437 			start = max_low;
438 
439 		/* Find and exclude any reserved regions */
440 		for_each_memblock(reserved, res) {
441 			unsigned long res_start, res_end;
442 
443 			res_start = memblock_region_reserved_base_pfn(res);
444 			res_end = memblock_region_reserved_end_pfn(res);
445 
446 			if (res_end < start)
447 				continue;
448 			if (res_start < start)
449 				res_start = start;
450 			if (res_start > end)
451 				res_start = end;
452 			if (res_end > end)
453 				res_end = end;
454 			if (res_start != start)
455 				free_area_high(start, res_start);
456 			start = res_end;
457 			if (start == end)
458 				break;
459 		}
460 
461 		/* And now free anything which remains */
462 		if (start < end)
463 			free_area_high(start, end);
464 	}
465 #endif
466 }
467 
468 /*
469  * mem_init() marks the free areas in the mem_map and tells us how much
470  * memory is free.  This is done after various parts of the system have
471  * claimed their memory after the kernel image.
472  */
473 void __init mem_init(void)
474 {
475 #ifdef CONFIG_HAVE_TCM
476 	/* These pointers are filled in on TCM detection */
477 	extern u32 dtcm_end;
478 	extern u32 itcm_end;
479 #endif
480 
481 	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
482 
483 	/* this will put all unused low memory onto the freelists */
484 	free_unused_memmap();
485 	free_all_bootmem();
486 
487 #ifdef CONFIG_SA1111
488 	/* now that our DMA memory is actually so designated, we can free it */
489 	free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
490 #endif
491 
492 	free_highpages();
493 
494 	mem_init_print_info(NULL);
495 
496 #define MLK(b, t) b, t, ((t) - (b)) >> 10
497 #define MLM(b, t) b, t, ((t) - (b)) >> 20
498 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
499 
500 	pr_notice("Virtual kernel memory layout:\n"
501 			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
502 #ifdef CONFIG_HAVE_TCM
503 			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
504 			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
505 #endif
506 			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
507 			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
508 			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
509 #ifdef CONFIG_HIGHMEM
510 			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
511 #endif
512 #ifdef CONFIG_MODULES
513 			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
514 #endif
515 			"      .text : 0x%p" " - 0x%p" "   (%4td kB)\n"
516 			"      .init : 0x%p" " - 0x%p" "   (%4td kB)\n"
517 			"      .data : 0x%p" " - 0x%p" "   (%4td kB)\n"
518 			"       .bss : 0x%p" " - 0x%p" "   (%4td kB)\n",
519 
520 			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
521 				(PAGE_SIZE)),
522 #ifdef CONFIG_HAVE_TCM
523 			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
524 			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
525 #endif
526 			MLK(FIXADDR_START, FIXADDR_END),
527 			MLM(VMALLOC_START, VMALLOC_END),
528 			MLM(PAGE_OFFSET, (unsigned long)high_memory),
529 #ifdef CONFIG_HIGHMEM
530 			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
531 				(PAGE_SIZE)),
532 #endif
533 #ifdef CONFIG_MODULES
534 			MLM(MODULES_VADDR, MODULES_END),
535 #endif
536 
537 			MLK_ROUNDUP(_text, _etext),
538 			MLK_ROUNDUP(__init_begin, __init_end),
539 			MLK_ROUNDUP(_sdata, _edata),
540 			MLK_ROUNDUP(__bss_start, __bss_stop));
541 
542 #undef MLK
543 #undef MLM
544 #undef MLK_ROUNDUP
545 
546 	/*
547 	 * Check boundaries twice: Some fundamental inconsistencies can
548 	 * be detected at build time already.
549 	 */
550 #ifdef CONFIG_MMU
551 	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
552 	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
553 #endif
554 
555 #ifdef CONFIG_HIGHMEM
556 	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
557 	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
558 #endif
559 
560 	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
561 		extern int sysctl_overcommit_memory;
562 		/*
563 		 * On a machine this small we won't get
564 		 * anywhere without overcommit, so turn
565 		 * it on by default.
566 		 */
567 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
568 	}
569 }
570 
571 #ifdef CONFIG_ARM_KERNMEM_PERMS
572 struct section_perm {
573 	unsigned long start;
574 	unsigned long end;
575 	pmdval_t mask;
576 	pmdval_t prot;
577 	pmdval_t clear;
578 };
579 
580 static struct section_perm nx_perms[] = {
581 	/* Make pages tables, etc before _stext RW (set NX). */
582 	{
583 		.start	= PAGE_OFFSET,
584 		.end	= (unsigned long)_stext,
585 		.mask	= ~PMD_SECT_XN,
586 		.prot	= PMD_SECT_XN,
587 	},
588 	/* Make init RW (set NX). */
589 	{
590 		.start	= (unsigned long)__init_begin,
591 		.end	= (unsigned long)_sdata,
592 		.mask	= ~PMD_SECT_XN,
593 		.prot	= PMD_SECT_XN,
594 	},
595 #ifdef CONFIG_DEBUG_RODATA
596 	/* Make rodata NX (set RO in ro_perms below). */
597 	{
598 		.start  = (unsigned long)__start_rodata,
599 		.end    = (unsigned long)__init_begin,
600 		.mask   = ~PMD_SECT_XN,
601 		.prot   = PMD_SECT_XN,
602 	},
603 #endif
604 };
605 
606 #ifdef CONFIG_DEBUG_RODATA
607 static struct section_perm ro_perms[] = {
608 	/* Make kernel code and rodata RX (set RO). */
609 	{
610 		.start  = (unsigned long)_stext,
611 		.end    = (unsigned long)__init_begin,
612 #ifdef CONFIG_ARM_LPAE
613 		.mask   = ~L_PMD_SECT_RDONLY,
614 		.prot   = L_PMD_SECT_RDONLY,
615 #else
616 		.mask   = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
617 		.prot   = PMD_SECT_APX | PMD_SECT_AP_WRITE,
618 		.clear  = PMD_SECT_AP_WRITE,
619 #endif
620 	},
621 };
622 #endif
623 
624 /*
625  * Updates section permissions only for the current mm (sections are
626  * copied into each mm). During startup, this is the init_mm. Is only
627  * safe to be called with preemption disabled, as under stop_machine().
628  */
629 static inline void section_update(unsigned long addr, pmdval_t mask,
630 				  pmdval_t prot)
631 {
632 	struct mm_struct *mm;
633 	pmd_t *pmd;
634 
635 	mm = current->active_mm;
636 	pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
637 
638 #ifdef CONFIG_ARM_LPAE
639 	pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
640 #else
641 	if (addr & SECTION_SIZE)
642 		pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
643 	else
644 		pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
645 #endif
646 	flush_pmd_entry(pmd);
647 	local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
648 }
649 
650 /* Make sure extended page tables are in use. */
651 static inline bool arch_has_strict_perms(void)
652 {
653 	if (cpu_architecture() < CPU_ARCH_ARMv6)
654 		return false;
655 
656 	return !!(get_cr() & CR_XP);
657 }
658 
659 #define set_section_perms(perms, field)	{				\
660 	size_t i;							\
661 	unsigned long addr;						\
662 									\
663 	if (!arch_has_strict_perms())					\
664 		return;							\
665 									\
666 	for (i = 0; i < ARRAY_SIZE(perms); i++) {			\
667 		if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||	\
668 		    !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {		\
669 			pr_err("BUG: section %lx-%lx not aligned to %lx\n", \
670 				perms[i].start, perms[i].end,		\
671 				SECTION_SIZE);				\
672 			continue;					\
673 		}							\
674 									\
675 		for (addr = perms[i].start;				\
676 		     addr < perms[i].end;				\
677 		     addr += SECTION_SIZE)				\
678 			section_update(addr, perms[i].mask,		\
679 				       perms[i].field);			\
680 	}								\
681 }
682 
683 static inline void fix_kernmem_perms(void)
684 {
685 	set_section_perms(nx_perms, prot);
686 }
687 
688 #ifdef CONFIG_DEBUG_RODATA
689 void mark_rodata_ro(void)
690 {
691 	set_section_perms(ro_perms, prot);
692 }
693 
694 void set_kernel_text_rw(void)
695 {
696 	set_section_perms(ro_perms, clear);
697 }
698 
699 void set_kernel_text_ro(void)
700 {
701 	set_section_perms(ro_perms, prot);
702 }
703 #endif /* CONFIG_DEBUG_RODATA */
704 
705 #else
706 static inline void fix_kernmem_perms(void) { }
707 #endif /* CONFIG_ARM_KERNMEM_PERMS */
708 
709 void free_tcmmem(void)
710 {
711 #ifdef CONFIG_HAVE_TCM
712 	extern char __tcm_start, __tcm_end;
713 
714 	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
715 	free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
716 #endif
717 }
718 
719 void free_initmem(void)
720 {
721 	fix_kernmem_perms();
722 	free_tcmmem();
723 
724 	poison_init_mem(__init_begin, __init_end - __init_begin);
725 	if (!machine_is_integrator() && !machine_is_cintegrator())
726 		free_initmem_default(-1);
727 }
728 
729 #ifdef CONFIG_BLK_DEV_INITRD
730 
731 static int keep_initrd;
732 
733 void free_initrd_mem(unsigned long start, unsigned long end)
734 {
735 	if (!keep_initrd) {
736 		if (start == initrd_start)
737 			start = round_down(start, PAGE_SIZE);
738 		if (end == initrd_end)
739 			end = round_up(end, PAGE_SIZE);
740 
741 		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
742 		free_reserved_area((void *)start, (void *)end, -1, "initrd");
743 	}
744 }
745 
746 static int __init keepinitrd_setup(char *__unused)
747 {
748 	keep_initrd = 1;
749 	return 1;
750 }
751 
752 __setup("keepinitrd", keepinitrd_setup);
753 #endif
754