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);
72 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
73 * currently assumes that for memory starting above 4G, 32-bit devices will
76 static phys_addr_t max_zone_dma_phys(void)
78 phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
79 return min(offset + (1ULL << 32), memblock_end_of_DRAM());
82 static void __init zone_sizes_init(unsigned long min, unsigned long max)
84 struct memblock_region *reg;
85 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
86 unsigned long max_dma = min;
88 memset(zone_size, 0, sizeof(zone_size));
90 /* 4GB maximum for 32-bit only capable devices */
91 if (IS_ENABLED(CONFIG_ZONE_DMA)) {
92 max_dma = PFN_DOWN(max_zone_dma_phys());
93 zone_size[ZONE_DMA] = max_dma - min;
95 zone_size[ZONE_NORMAL] = max - max_dma;
97 memcpy(zhole_size, zone_size, sizeof(zhole_size));
99 for_each_memblock(memory, reg) {
100 unsigned long start = memblock_region_memory_base_pfn(reg);
101 unsigned long end = memblock_region_memory_end_pfn(reg);
106 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {
107 unsigned long dma_end = min(end, max_dma);
108 zhole_size[ZONE_DMA] -= dma_end - start;
112 unsigned long normal_end = min(end, max);
113 unsigned long normal_start = max(start, max_dma);
114 zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
118 free_area_init_node(0, zone_size, min, zhole_size);
121 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
122 int pfn_valid(unsigned long pfn)
124 return memblock_is_memory(pfn << PAGE_SHIFT);
126 EXPORT_SYMBOL(pfn_valid);
129 #ifndef CONFIG_SPARSEMEM
130 static void arm64_memory_present(void)
134 static void arm64_memory_present(void)
136 struct memblock_region *reg;
138 for_each_memblock(memory, reg)
139 memory_present(0, memblock_region_memory_base_pfn(reg),
140 memblock_region_memory_end_pfn(reg));
144 void __init arm64_memblock_init(void)
146 u64 *reserve_map, base, size;
147 phys_addr_t dma_phys_limit = 0;
150 * Register the kernel text, kernel data, initrd, and initial
151 * pagetables with memblock.
153 memblock_reserve(__pa(_text), _end - _text);
154 #ifdef CONFIG_BLK_DEV_INITRD
155 if (phys_initrd_size) {
156 memblock_reserve(phys_initrd_start, phys_initrd_size);
158 /* Now convert initrd to virtual addresses */
159 initrd_start = __phys_to_virt(phys_initrd_start);
160 initrd_end = initrd_start + phys_initrd_size;
164 /* Reserve the dtb region */
165 memblock_reserve(virt_to_phys(initial_boot_params),
166 be32_to_cpu(initial_boot_params->totalsize));
169 * Process the reserve map. This will probably overlap the initrd
170 * and dtb locations which are already reserved, but overlapping
171 * doesn't hurt anything
173 reserve_map = ((void*)initial_boot_params) +
174 be32_to_cpu(initial_boot_params->off_mem_rsvmap);
176 base = be64_to_cpup(reserve_map++);
177 size = be64_to_cpup(reserve_map++);
180 memblock_reserve(base, size);
183 early_init_fdt_scan_reserved_mem();
185 /* 4GB maximum for 32-bit only capable devices */
186 if (IS_ENABLED(CONFIG_ZONE_DMA))
187 dma_phys_limit = max_zone_dma_phys();
188 dma_contiguous_reserve(dma_phys_limit);
190 memblock_allow_resize();
194 void __init bootmem_init(void)
196 unsigned long min, max;
198 min = PFN_UP(memblock_start_of_DRAM());
199 max = PFN_DOWN(memblock_end_of_DRAM());
202 * Sparsemem tries to allocate bootmem in memory_present(), so must be
203 * done after the fixed reservations.
205 arm64_memory_present();
208 zone_sizes_init(min, max);
210 high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
211 max_pfn = max_low_pfn = max;
215 * Poison init memory with an undefined instruction (0x0).
217 static inline void poison_init_mem(void *s, size_t count)
222 #ifndef CONFIG_SPARSEMEM_VMEMMAP
223 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
225 struct page *start_pg, *end_pg;
226 unsigned long pg, pgend;
229 * Convert start_pfn/end_pfn to a struct page pointer.
231 start_pg = pfn_to_page(start_pfn - 1) + 1;
232 end_pg = pfn_to_page(end_pfn - 1) + 1;
235 * Convert to physical addresses, and round start upwards and end
238 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
239 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
242 * If there are free pages between these, free the section of the
246 free_bootmem(pg, pgend - pg);
250 * The mem_map array can get very big. Free the unused area of the memory map.
252 static void __init free_unused_memmap(void)
254 unsigned long start, prev_end = 0;
255 struct memblock_region *reg;
257 for_each_memblock(memory, reg) {
258 start = __phys_to_pfn(reg->base);
260 #ifdef CONFIG_SPARSEMEM
262 * Take care not to free memmap entries that don't exist due
263 * to SPARSEMEM sections which aren't present.
265 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
268 * If we had a previous bank, and there is a space between the
269 * current bank and the previous, free it.
271 if (prev_end && prev_end < start)
272 free_memmap(prev_end, start);
275 * Align up here since the VM subsystem insists that the
276 * memmap entries are valid from the bank end aligned to
277 * MAX_ORDER_NR_PAGES.
279 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
283 #ifdef CONFIG_SPARSEMEM
284 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
285 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
288 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
291 * mem_init() marks the free areas in the mem_map and tells us how much memory
292 * is free. This is done after various parts of the system have claimed their
293 * memory after the kernel image.
295 void __init mem_init(void)
297 unsigned long reserved_pages, free_pages;
298 struct memblock_region *reg;
300 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
302 #ifndef CONFIG_SPARSEMEM_VMEMMAP
303 /* this will put all unused low memory onto the freelists */
304 free_unused_memmap();
307 totalram_pages += free_all_bootmem();
309 reserved_pages = free_pages = 0;
311 for_each_memblock(memory, reg) {
312 unsigned int pfn1, pfn2;
313 struct page *page, *end;
315 pfn1 = __phys_to_pfn(reg->base);
316 pfn2 = pfn1 + __phys_to_pfn(reg->size);
318 page = pfn_to_page(pfn1);
319 end = pfn_to_page(pfn2 - 1) + 1;
322 if (PageReserved(page))
324 else if (!page_count(page))
327 } while (page < end);
331 * Since our memory may not be contiguous, calculate the real number
332 * of pages we have in this system.
336 for_each_memblock(memory, reg) {
337 unsigned long pages = memblock_region_memory_end_pfn(reg) -
338 memblock_region_memory_base_pfn(reg);
339 num_physpages += pages;
340 printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
342 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
344 pr_notice("Memory: %luk/%luk available, %luk reserved\n",
345 nr_free_pages() << (PAGE_SHIFT-10),
346 free_pages << (PAGE_SHIFT-10),
347 reserved_pages << (PAGE_SHIFT-10));
349 #define MLK(b, t) b, t, ((t) - (b)) >> 10
350 #define MLM(b, t) b, t, ((t) - (b)) >> 20
351 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
353 pr_notice("Virtual kernel memory layout:\n"
354 " vmalloc : 0x%16lx - 0x%16lx (%6ld MB)\n"
355 #ifdef CONFIG_SPARSEMEM_VMEMMAP
356 " vmemmap : 0x%16lx - 0x%16lx (%6ld MB)\n"
358 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
359 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
360 " .init : 0x%p" " - 0x%p" " (%6ld kB)\n"
361 " .text : 0x%p" " - 0x%p" " (%6ld kB)\n"
362 " .data : 0x%p" " - 0x%p" " (%6ld kB)\n",
363 MLM(VMALLOC_START, VMALLOC_END),
364 #ifdef CONFIG_SPARSEMEM_VMEMMAP
365 MLM((unsigned long)virt_to_page(PAGE_OFFSET),
366 (unsigned long)virt_to_page(high_memory)),
368 MLM(MODULES_VADDR, MODULES_END),
369 MLM(PAGE_OFFSET, (unsigned long)high_memory),
371 MLK_ROUNDUP(__init_begin, __init_end),
372 MLK_ROUNDUP(_text, _etext),
373 MLK_ROUNDUP(_sdata, _edata));
380 * Check boundaries twice: Some fundamental inconsistencies can be
381 * detected at build time already.
384 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
386 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
387 BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
389 if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
390 extern int sysctl_overcommit_memory;
392 * On a machine this small we won't get anywhere without
393 * overcommit, so turn it on by default.
395 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
399 void free_initmem(void)
401 poison_init_mem(__init_begin, __init_end - __init_begin);
402 free_initmem_default(0);
405 #ifdef CONFIG_BLK_DEV_INITRD
407 static int keep_initrd;
409 void free_initrd_mem(unsigned long start, unsigned long end)
412 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
413 free_reserved_area(start, end, 0, "initrd");
417 static int __init keepinitrd_setup(char *__unused)
423 __setup("keepinitrd", keepinitrd_setup);