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 #define PFN_MASK ((1UL << (64 - PAGE_SHIFT)) - 1)
115 int pfn_valid(unsigned long pfn)
117 return (pfn & PFN_MASK) == pfn && memblock_is_memory(pfn << PAGE_SHIFT);
119 EXPORT_SYMBOL(pfn_valid);
122 #ifndef CONFIG_SPARSEMEM
123 static void arm64_memory_present(void)
127 static void arm64_memory_present(void)
129 struct memblock_region *reg;
131 for_each_memblock(memory, reg)
132 memory_present(0, memblock_region_memory_base_pfn(reg),
133 memblock_region_memory_end_pfn(reg));
137 void __init arm64_memblock_init(void)
139 u64 *reserve_map, base, size;
142 * Register the kernel text, kernel data, initrd, and initial
143 * pagetables with memblock.
145 memblock_reserve(__pa(_text), _end - _text);
146 #ifdef CONFIG_BLK_DEV_INITRD
147 if (phys_initrd_size) {
148 memblock_reserve(phys_initrd_start, phys_initrd_size);
150 /* Now convert initrd to virtual addresses */
151 initrd_start = __phys_to_virt(phys_initrd_start);
152 initrd_end = initrd_start + phys_initrd_size;
156 /* Reserve the dtb region */
157 memblock_reserve(virt_to_phys(initial_boot_params),
158 be32_to_cpu(initial_boot_params->totalsize));
161 * Process the reserve map. This will probably overlap the initrd
162 * and dtb locations which are already reserved, but overlapping
163 * doesn't hurt anything
165 reserve_map = ((void*)initial_boot_params) +
166 be32_to_cpu(initial_boot_params->off_mem_rsvmap);
168 base = be64_to_cpup(reserve_map++);
169 size = be64_to_cpup(reserve_map++);
172 memblock_reserve(base, size);
175 early_init_fdt_scan_reserved_mem();
176 dma_contiguous_reserve(0);
178 memblock_allow_resize();
182 void __init bootmem_init(void)
184 unsigned long min, max;
186 min = PFN_UP(memblock_start_of_DRAM());
187 max = PFN_DOWN(memblock_end_of_DRAM());
190 * Sparsemem tries to allocate bootmem in memory_present(), so must be
191 * done after the fixed reservations.
193 arm64_memory_present();
196 zone_sizes_init(min, max);
198 high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
199 max_pfn = max_low_pfn = max;
203 * Poison init memory with an undefined instruction (0x0).
205 static inline void poison_init_mem(void *s, size_t count)
210 #ifndef CONFIG_SPARSEMEM_VMEMMAP
211 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
213 struct page *start_pg, *end_pg;
214 unsigned long pg, pgend;
217 * Convert start_pfn/end_pfn to a struct page pointer.
219 start_pg = pfn_to_page(start_pfn - 1) + 1;
220 end_pg = pfn_to_page(end_pfn - 1) + 1;
223 * Convert to physical addresses, and round start upwards and end
226 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
227 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
230 * If there are free pages between these, free the section of the
234 free_bootmem(pg, pgend - pg);
238 * The mem_map array can get very big. Free the unused area of the memory map.
240 static void __init free_unused_memmap(void)
242 unsigned long start, prev_end = 0;
243 struct memblock_region *reg;
245 for_each_memblock(memory, reg) {
246 start = __phys_to_pfn(reg->base);
248 #ifdef CONFIG_SPARSEMEM
250 * Take care not to free memmap entries that don't exist due
251 * to SPARSEMEM sections which aren't present.
253 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
256 * If we had a previous bank, and there is a space between the
257 * current bank and the previous, free it.
259 if (prev_end && prev_end < start)
260 free_memmap(prev_end, start);
263 * Align up here since the VM subsystem insists that the
264 * memmap entries are valid from the bank end aligned to
265 * MAX_ORDER_NR_PAGES.
267 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
271 #ifdef CONFIG_SPARSEMEM
272 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
273 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
276 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
279 * mem_init() marks the free areas in the mem_map and tells us how much memory
280 * is free. This is done after various parts of the system have claimed their
281 * memory after the kernel image.
283 void __init mem_init(void)
285 unsigned long reserved_pages, free_pages;
286 struct memblock_region *reg;
288 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
290 #ifndef CONFIG_SPARSEMEM_VMEMMAP
291 /* this will put all unused low memory onto the freelists */
292 free_unused_memmap();
295 totalram_pages += free_all_bootmem();
297 reserved_pages = free_pages = 0;
299 for_each_memblock(memory, reg) {
300 unsigned int pfn1, pfn2;
301 struct page *page, *end;
303 pfn1 = __phys_to_pfn(reg->base);
304 pfn2 = pfn1 + __phys_to_pfn(reg->size);
306 page = pfn_to_page(pfn1);
307 end = pfn_to_page(pfn2 - 1) + 1;
310 if (PageReserved(page))
312 else if (!page_count(page))
315 } while (page < end);
319 * Since our memory may not be contiguous, calculate the real number
320 * of pages we have in this system.
324 for_each_memblock(memory, reg) {
325 unsigned long pages = memblock_region_memory_end_pfn(reg) -
326 memblock_region_memory_base_pfn(reg);
327 num_physpages += pages;
328 printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
330 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
332 pr_notice("Memory: %luk/%luk available, %luk reserved\n",
333 nr_free_pages() << (PAGE_SHIFT-10),
334 free_pages << (PAGE_SHIFT-10),
335 reserved_pages << (PAGE_SHIFT-10));
337 #define MLK(b, t) b, t, ((t) - (b)) >> 10
338 #define MLM(b, t) b, t, ((t) - (b)) >> 20
339 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
341 pr_notice("Virtual kernel memory layout:\n"
342 " vmalloc : 0x%16lx - 0x%16lx (%6ld MB)\n"
343 #ifdef CONFIG_SPARSEMEM_VMEMMAP
344 " vmemmap : 0x%16lx - 0x%16lx (%6ld MB)\n"
346 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
347 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
348 " .init : 0x%p" " - 0x%p" " (%6ld kB)\n"
349 " .text : 0x%p" " - 0x%p" " (%6ld kB)\n"
350 " .data : 0x%p" " - 0x%p" " (%6ld kB)\n",
351 MLM(VMALLOC_START, VMALLOC_END),
352 #ifdef CONFIG_SPARSEMEM_VMEMMAP
353 MLM((unsigned long)virt_to_page(PAGE_OFFSET),
354 (unsigned long)virt_to_page(high_memory)),
356 MLM(MODULES_VADDR, MODULES_END),
357 MLM(PAGE_OFFSET, (unsigned long)high_memory),
359 MLK_ROUNDUP(__init_begin, __init_end),
360 MLK_ROUNDUP(_text, _etext),
361 MLK_ROUNDUP(_sdata, _edata));
368 * Check boundaries twice: Some fundamental inconsistencies can be
369 * detected at build time already.
372 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
374 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
375 BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
377 if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
378 extern int sysctl_overcommit_memory;
380 * On a machine this small we won't get anywhere without
381 * overcommit, so turn it on by default.
383 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
387 void free_initmem(void)
389 poison_init_mem(__init_begin, __init_end - __init_begin);
390 free_initmem_default(0);
393 #ifdef CONFIG_BLK_DEV_INITRD
395 static int keep_initrd;
397 void free_initrd_mem(unsigned long start, unsigned long end)
400 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
401 free_reserved_area(start, end, 0, "initrd");
405 static int __init keepinitrd_setup(char *__unused)
411 __setup("keepinitrd", keepinitrd_setup);