2 * Based on arch/arm/mm/init.c
4 * Copyright (C) 1995-2005 Russell King
5 * Copyright (C) 2012 ARM Ltd.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #include <linux/kernel.h>
21 #include <linux/export.h>
22 #include <linux/errno.h>
23 #include <linux/swap.h>
24 #include <linux/init.h>
25 #include <linux/bootmem.h>
26 #include <linux/mman.h>
27 #include <linux/nodemask.h>
28 #include <linux/initrd.h>
29 #include <linux/gfp.h>
30 #include <linux/memblock.h>
31 #include <linux/sort.h>
32 #include <linux/of_fdt.h>
35 #include <asm/sections.h>
36 #include <asm/setup.h>
37 #include <asm/sizes.h>
42 static unsigned long phys_initrd_start __initdata = 0;
43 static unsigned long phys_initrd_size __initdata = 0;
45 phys_addr_t memstart_addr __read_mostly = 0;
47 void __init early_init_dt_setup_initrd_arch(unsigned long start,
50 phys_initrd_start = start;
51 phys_initrd_size = end - start;
54 static int __init early_initrd(char *p)
56 unsigned long start, size;
59 start = memparse(p, &endp);
61 size = memparse(endp + 1, NULL);
63 phys_initrd_start = start;
64 phys_initrd_size = size;
68 early_param("initrd", early_initrd);
70 #define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
72 static void __init zone_sizes_init(unsigned long min, unsigned long max)
74 struct memblock_region *reg;
75 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
76 unsigned long max_dma32 = min;
78 memset(zone_size, 0, sizeof(zone_size));
80 #ifdef CONFIG_ZONE_DMA32
81 /* 4GB maximum for 32-bit only capable devices */
82 max_dma32 = min(max, MAX_DMA32_PFN);
83 zone_size[ZONE_DMA32] = max(min, max_dma32) - min;
85 zone_size[ZONE_NORMAL] = max - max_dma32;
87 memcpy(zhole_size, zone_size, sizeof(zhole_size));
89 for_each_memblock(memory, reg) {
90 unsigned long start = memblock_region_memory_base_pfn(reg);
91 unsigned long end = memblock_region_memory_end_pfn(reg);
95 #ifdef CONFIG_ZONE_DMA32
96 if (start < max_dma32) {
97 unsigned long dma_end = min(end, max_dma32);
98 zhole_size[ZONE_DMA32] -= dma_end - start;
101 if (end > max_dma32) {
102 unsigned long normal_end = min(end, max);
103 unsigned long normal_start = max(start, max_dma32);
104 zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
108 free_area_init_node(0, zone_size, min, zhole_size);
111 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
112 int pfn_valid(unsigned long pfn)
114 return memblock_is_memory(pfn << PAGE_SHIFT);
116 EXPORT_SYMBOL(pfn_valid);
119 #ifndef CONFIG_SPARSEMEM
120 static void arm64_memory_present(void)
124 static void arm64_memory_present(void)
126 struct memblock_region *reg;
128 for_each_memblock(memory, reg)
129 memory_present(0, memblock_region_memory_base_pfn(reg),
130 memblock_region_memory_end_pfn(reg));
134 void __init arm64_memblock_init(void)
136 u64 *reserve_map, base, size;
138 /* Register the kernel text, kernel data and initrd with memblock */
139 memblock_reserve(__pa(_text), _end - _text);
140 #ifdef CONFIG_BLK_DEV_INITRD
141 if (phys_initrd_size) {
142 memblock_reserve(phys_initrd_start, phys_initrd_size);
144 /* Now convert initrd to virtual addresses */
145 initrd_start = __phys_to_virt(phys_initrd_start);
146 initrd_end = initrd_start + phys_initrd_size;
151 * Reserve the page tables. These are already in use,
152 * and can only be in node 0.
154 memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
155 memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
157 /* Reserve the dtb region */
158 memblock_reserve(virt_to_phys(initial_boot_params),
159 be32_to_cpu(initial_boot_params->totalsize));
162 * Process the reserve map. This will probably overlap the initrd
163 * and dtb locations which are already reserved, but overlapping
164 * doesn't hurt anything
166 reserve_map = ((void*)initial_boot_params) +
167 be32_to_cpu(initial_boot_params->off_mem_rsvmap);
169 base = be64_to_cpup(reserve_map++);
170 size = be64_to_cpup(reserve_map++);
173 memblock_reserve(base, size);
176 memblock_allow_resize();
180 void __init bootmem_init(void)
182 unsigned long min, max;
184 min = PFN_UP(memblock_start_of_DRAM());
185 max = PFN_DOWN(memblock_end_of_DRAM());
188 * Sparsemem tries to allocate bootmem in memory_present(), so must be
189 * done after the fixed reservations.
191 arm64_memory_present();
194 zone_sizes_init(min, max);
196 high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
197 max_pfn = max_low_pfn = max;
200 static inline int free_area(unsigned long pfn, unsigned long end, char *s)
202 unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
204 for (; pfn < end; pfn++) {
205 struct page *page = pfn_to_page(pfn);
206 ClearPageReserved(page);
207 init_page_count(page);
213 pr_info("Freeing %s memory: %dK\n", s, size);
219 * Poison init memory with an undefined instruction (0x0).
221 static inline void poison_init_mem(void *s, size_t count)
226 #ifndef CONFIG_SPARSEMEM_VMEMMAP
227 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
229 struct page *start_pg, *end_pg;
230 unsigned long pg, pgend;
233 * Convert start_pfn/end_pfn to a struct page pointer.
235 start_pg = pfn_to_page(start_pfn - 1) + 1;
236 end_pg = pfn_to_page(end_pfn - 1) + 1;
239 * Convert to physical addresses, and round start upwards and end
242 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
243 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
246 * If there are free pages between these, free the section of the
250 free_bootmem(pg, pgend - pg);
254 * The mem_map array can get very big. Free the unused area of the memory map.
256 static void __init free_unused_memmap(void)
258 unsigned long start, prev_end = 0;
259 struct memblock_region *reg;
261 for_each_memblock(memory, reg) {
262 start = __phys_to_pfn(reg->base);
264 #ifdef CONFIG_SPARSEMEM
266 * Take care not to free memmap entries that don't exist due
267 * to SPARSEMEM sections which aren't present.
269 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
272 * If we had a previous bank, and there is a space between the
273 * current bank and the previous, free it.
275 if (prev_end && prev_end < start)
276 free_memmap(prev_end, start);
279 * Align up here since the VM subsystem insists that the
280 * memmap entries are valid from the bank end aligned to
281 * MAX_ORDER_NR_PAGES.
283 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
287 #ifdef CONFIG_SPARSEMEM
288 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
289 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
292 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
295 * mem_init() marks the free areas in the mem_map and tells us how much memory
296 * is free. This is done after various parts of the system have claimed their
297 * memory after the kernel image.
299 void __init mem_init(void)
301 unsigned long reserved_pages, free_pages;
302 struct memblock_region *reg;
304 arm64_swiotlb_init();
306 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
308 #ifndef CONFIG_SPARSEMEM_VMEMMAP
309 /* this will put all unused low memory onto the freelists */
310 free_unused_memmap();
313 totalram_pages += free_all_bootmem();
315 reserved_pages = free_pages = 0;
317 for_each_memblock(memory, reg) {
318 unsigned int pfn1, pfn2;
319 struct page *page, *end;
321 pfn1 = __phys_to_pfn(reg->base);
322 pfn2 = pfn1 + __phys_to_pfn(reg->size);
324 page = pfn_to_page(pfn1);
325 end = pfn_to_page(pfn2 - 1) + 1;
328 if (PageReserved(page))
330 else if (!page_count(page))
333 } while (page < end);
337 * Since our memory may not be contiguous, calculate the real number
338 * of pages we have in this system.
342 for_each_memblock(memory, reg) {
343 unsigned long pages = memblock_region_memory_end_pfn(reg) -
344 memblock_region_memory_base_pfn(reg);
345 num_physpages += pages;
346 printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
348 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
350 pr_notice("Memory: %luk/%luk available, %luk reserved\n",
351 nr_free_pages() << (PAGE_SHIFT-10),
352 free_pages << (PAGE_SHIFT-10),
353 reserved_pages << (PAGE_SHIFT-10));
355 #define MLK(b, t) b, t, ((t) - (b)) >> 10
356 #define MLM(b, t) b, t, ((t) - (b)) >> 20
357 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
359 pr_notice("Virtual kernel memory layout:\n"
360 " vmalloc : 0x%16lx - 0x%16lx (%6ld MB)\n"
361 #ifdef CONFIG_SPARSEMEM_VMEMMAP
362 " vmemmap : 0x%16lx - 0x%16lx (%6ld MB)\n"
364 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
365 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
366 " .init : 0x%p" " - 0x%p" " (%6ld kB)\n"
367 " .text : 0x%p" " - 0x%p" " (%6ld kB)\n"
368 " .data : 0x%p" " - 0x%p" " (%6ld kB)\n",
369 MLM(VMALLOC_START, VMALLOC_END),
370 #ifdef CONFIG_SPARSEMEM_VMEMMAP
371 MLM((unsigned long)virt_to_page(PAGE_OFFSET),
372 (unsigned long)virt_to_page(high_memory)),
374 MLM(MODULES_VADDR, MODULES_END),
375 MLM(PAGE_OFFSET, (unsigned long)high_memory),
377 MLK_ROUNDUP(__init_begin, __init_end),
378 MLK_ROUNDUP(_text, _etext),
379 MLK_ROUNDUP(_sdata, _edata));
386 * Check boundaries twice: Some fundamental inconsistencies can be
387 * detected at build time already.
390 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
392 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
393 BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
395 if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
396 extern int sysctl_overcommit_memory;
398 * On a machine this small we won't get anywhere without
399 * overcommit, so turn it on by default.
401 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
405 void free_initmem(void)
407 poison_init_mem(__init_begin, __init_end - __init_begin);
408 totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
409 __phys_to_pfn(__pa(__init_end)),
413 #ifdef CONFIG_BLK_DEV_INITRD
415 static int keep_initrd;
417 void free_initrd_mem(unsigned long start, unsigned long end)
420 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
421 totalram_pages += free_area(__phys_to_pfn(__pa(start)),
422 __phys_to_pfn(__pa(end)),
427 static int __init keepinitrd_setup(char *__unused)
433 __setup("keepinitrd", keepinitrd_setup);