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>
33 #include <linux/dma-mapping.h>
34 #include <linux/dma-contiguous.h>
37 #include <asm/sections.h>
38 #include <asm/setup.h>
39 #include <asm/sizes.h>
44 static unsigned long phys_initrd_start __initdata = 0;
45 static unsigned long phys_initrd_size __initdata = 0;
47 phys_addr_t memstart_addr __read_mostly = 0;
49 void __init early_init_dt_setup_initrd_arch(u64 start, u64 end)
51 phys_initrd_start = start;
52 phys_initrd_size = end - start;
55 static int __init early_initrd(char *p)
57 unsigned long start, size;
60 start = memparse(p, &endp);
62 size = memparse(endp + 1, NULL);
64 phys_initrd_start = start;
65 phys_initrd_size = size;
69 early_param("initrd", early_initrd);
71 static void __init zone_sizes_init(unsigned long min, unsigned long max)
73 struct memblock_region *reg;
74 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
75 unsigned long max_dma = min;
77 memset(zone_size, 0, sizeof(zone_size));
79 /* 4GB maximum for 32-bit only capable devices */
80 if (IS_ENABLED(CONFIG_ZONE_DMA)) {
81 unsigned long max_dma_phys =
82 (unsigned long)dma_to_phys(NULL, DMA_BIT_MASK(32) + 1);
83 max_dma = max(min, min(max, max_dma_phys >> PAGE_SHIFT));
84 zone_size[ZONE_DMA] = max_dma - min;
86 zone_size[ZONE_NORMAL] = max - max_dma;
88 memcpy(zhole_size, zone_size, sizeof(zhole_size));
90 for_each_memblock(memory, reg) {
91 unsigned long start = memblock_region_memory_base_pfn(reg);
92 unsigned long end = memblock_region_memory_end_pfn(reg);
97 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {
98 unsigned long dma_end = min(end, max_dma);
99 zhole_size[ZONE_DMA] -= dma_end - start;
103 unsigned long normal_end = min(end, max);
104 unsigned long normal_start = max(start, max_dma);
105 zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
109 free_area_init_node(0, zone_size, min, zhole_size);
112 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
113 int pfn_valid(unsigned long pfn)
115 return memblock_is_memory(pfn << PAGE_SHIFT);
117 EXPORT_SYMBOL(pfn_valid);
120 #ifndef CONFIG_SPARSEMEM
121 static void arm64_memory_present(void)
125 static void arm64_memory_present(void)
127 struct memblock_region *reg;
129 for_each_memblock(memory, reg)
130 memory_present(0, memblock_region_memory_base_pfn(reg),
131 memblock_region_memory_end_pfn(reg));
135 void __init arm64_memblock_init(void)
137 u64 *reserve_map, base, size;
140 * Register the kernel text, kernel data, initrd, and initial
141 * pagetables with memblock.
143 memblock_reserve(__pa(_text), _end - _text);
144 #ifdef CONFIG_BLK_DEV_INITRD
145 if (phys_initrd_size) {
146 memblock_reserve(phys_initrd_start, phys_initrd_size);
148 /* Now convert initrd to virtual addresses */
149 initrd_start = __phys_to_virt(phys_initrd_start);
150 initrd_end = initrd_start + phys_initrd_size;
154 /* Reserve the dtb region */
155 memblock_reserve(virt_to_phys(initial_boot_params),
156 be32_to_cpu(initial_boot_params->totalsize));
159 * Process the reserve map. This will probably overlap the initrd
160 * and dtb locations which are already reserved, but overlapping
161 * doesn't hurt anything
163 reserve_map = ((void*)initial_boot_params) +
164 be32_to_cpu(initial_boot_params->off_mem_rsvmap);
166 base = be64_to_cpup(reserve_map++);
167 size = be64_to_cpup(reserve_map++);
170 memblock_reserve(base, size);
173 early_init_fdt_scan_reserved_mem();
174 dma_contiguous_reserve(0);
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;
201 * Poison init memory with an undefined instruction (0x0).
203 static inline void poison_init_mem(void *s, size_t count)
208 #ifndef CONFIG_SPARSEMEM_VMEMMAP
209 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
211 struct page *start_pg, *end_pg;
212 unsigned long pg, pgend;
215 * Convert start_pfn/end_pfn to a struct page pointer.
217 start_pg = pfn_to_page(start_pfn - 1) + 1;
218 end_pg = pfn_to_page(end_pfn - 1) + 1;
221 * Convert to physical addresses, and round start upwards and end
224 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
225 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
228 * If there are free pages between these, free the section of the
232 free_bootmem(pg, pgend - pg);
236 * The mem_map array can get very big. Free the unused area of the memory map.
238 static void __init free_unused_memmap(void)
240 unsigned long start, prev_end = 0;
241 struct memblock_region *reg;
243 for_each_memblock(memory, reg) {
244 start = __phys_to_pfn(reg->base);
246 #ifdef CONFIG_SPARSEMEM
248 * Take care not to free memmap entries that don't exist due
249 * to SPARSEMEM sections which aren't present.
251 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
254 * If we had a previous bank, and there is a space between the
255 * current bank and the previous, free it.
257 if (prev_end && prev_end < start)
258 free_memmap(prev_end, start);
261 * Align up here since the VM subsystem insists that the
262 * memmap entries are valid from the bank end aligned to
263 * MAX_ORDER_NR_PAGES.
265 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
269 #ifdef CONFIG_SPARSEMEM
270 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
271 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
274 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
277 * mem_init() marks the free areas in the mem_map and tells us how much memory
278 * is free. This is done after various parts of the system have claimed their
279 * memory after the kernel image.
281 void __init mem_init(void)
283 unsigned long reserved_pages, free_pages;
284 struct memblock_region *reg;
286 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
288 #ifndef CONFIG_SPARSEMEM_VMEMMAP
289 /* this will put all unused low memory onto the freelists */
290 free_unused_memmap();
293 totalram_pages += free_all_bootmem();
295 reserved_pages = free_pages = 0;
297 for_each_memblock(memory, reg) {
298 unsigned int pfn1, pfn2;
299 struct page *page, *end;
301 pfn1 = __phys_to_pfn(reg->base);
302 pfn2 = pfn1 + __phys_to_pfn(reg->size);
304 page = pfn_to_page(pfn1);
305 end = pfn_to_page(pfn2 - 1) + 1;
308 if (PageReserved(page))
310 else if (!page_count(page))
313 } while (page < end);
317 * Since our memory may not be contiguous, calculate the real number
318 * of pages we have in this system.
322 for_each_memblock(memory, reg) {
323 unsigned long pages = memblock_region_memory_end_pfn(reg) -
324 memblock_region_memory_base_pfn(reg);
325 num_physpages += pages;
326 printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
328 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
330 pr_notice("Memory: %luk/%luk available, %luk reserved\n",
331 nr_free_pages() << (PAGE_SHIFT-10),
332 free_pages << (PAGE_SHIFT-10),
333 reserved_pages << (PAGE_SHIFT-10));
335 #define MLK(b, t) b, t, ((t) - (b)) >> 10
336 #define MLM(b, t) b, t, ((t) - (b)) >> 20
337 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
339 pr_notice("Virtual kernel memory layout:\n"
340 " vmalloc : 0x%16lx - 0x%16lx (%6ld MB)\n"
341 #ifdef CONFIG_SPARSEMEM_VMEMMAP
342 " vmemmap : 0x%16lx - 0x%16lx (%6ld MB)\n"
344 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
345 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
346 " .init : 0x%p" " - 0x%p" " (%6ld kB)\n"
347 " .text : 0x%p" " - 0x%p" " (%6ld kB)\n"
348 " .data : 0x%p" " - 0x%p" " (%6ld kB)\n",
349 MLM(VMALLOC_START, VMALLOC_END),
350 #ifdef CONFIG_SPARSEMEM_VMEMMAP
351 MLM((unsigned long)virt_to_page(PAGE_OFFSET),
352 (unsigned long)virt_to_page(high_memory)),
354 MLM(MODULES_VADDR, MODULES_END),
355 MLM(PAGE_OFFSET, (unsigned long)high_memory),
357 MLK_ROUNDUP(__init_begin, __init_end),
358 MLK_ROUNDUP(_text, _etext),
359 MLK_ROUNDUP(_sdata, _edata));
366 * Check boundaries twice: Some fundamental inconsistencies can be
367 * detected at build time already.
370 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
372 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
373 BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
375 if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
376 extern int sysctl_overcommit_memory;
378 * On a machine this small we won't get anywhere without
379 * overcommit, so turn it on by default.
381 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
385 void free_initmem(void)
387 poison_init_mem(__init_begin, __init_end - __init_begin);
388 free_initmem_default(0);
391 #ifdef CONFIG_BLK_DEV_INITRD
393 static int keep_initrd;
395 void free_initrd_mem(unsigned long start, unsigned long end)
398 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
399 free_reserved_area(start, end, 0, "initrd");
403 static int __init keepinitrd_setup(char *__unused)
409 __setup("keepinitrd", keepinitrd_setup);