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>
35 #include <linux/efi.h>
37 #include <asm/fixmap.h>
38 #include <asm/sections.h>
39 #include <asm/setup.h>
40 #include <asm/sizes.h>
45 phys_addr_t memstart_addr __read_mostly = 0;
47 #ifdef CONFIG_BLK_DEV_INITRD
48 static int __init early_initrd(char *p)
50 unsigned long start, size;
53 start = memparse(p, &endp);
55 size = memparse(endp + 1, NULL);
57 initrd_start = (unsigned long)__va(start);
58 initrd_end = (unsigned long)__va(start + size);
62 early_param("initrd", early_initrd);
66 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
67 * currently assumes that for memory starting above 4G, 32-bit devices will
70 static phys_addr_t max_zone_dma_phys(void)
72 phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
73 return min(offset + (1ULL << 32), memblock_end_of_DRAM());
76 static void __init zone_sizes_init(unsigned long min, unsigned long max)
78 struct memblock_region *reg;
79 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
80 unsigned long max_dma = min;
82 memset(zone_size, 0, sizeof(zone_size));
84 /* 4GB maximum for 32-bit only capable devices */
85 if (IS_ENABLED(CONFIG_ZONE_DMA)) {
86 max_dma = PFN_DOWN(max_zone_dma_phys());
87 zone_size[ZONE_DMA] = max_dma - min;
89 zone_size[ZONE_NORMAL] = max - max_dma;
91 memcpy(zhole_size, zone_size, sizeof(zhole_size));
93 for_each_memblock(memory, reg) {
94 unsigned long start = memblock_region_memory_base_pfn(reg);
95 unsigned long end = memblock_region_memory_end_pfn(reg);
100 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {
101 unsigned long dma_end = min(end, max_dma);
102 zhole_size[ZONE_DMA] -= dma_end - start;
106 unsigned long normal_end = min(end, max);
107 unsigned long normal_start = max(start, max_dma);
108 zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
112 free_area_init_node(0, zone_size, min, zhole_size);
115 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
116 int pfn_valid(unsigned long pfn)
118 return memblock_is_memory(pfn << PAGE_SHIFT);
120 EXPORT_SYMBOL(pfn_valid);
123 #ifndef CONFIG_SPARSEMEM
124 static void arm64_memory_present(void)
128 static void arm64_memory_present(void)
130 struct memblock_region *reg;
132 for_each_memblock(memory, reg)
133 memory_present(0, memblock_region_memory_base_pfn(reg),
134 memblock_region_memory_end_pfn(reg));
138 void __init arm64_memblock_init(void)
140 phys_addr_t dma_phys_limit = 0;
143 * Register the kernel text, kernel data, initrd, and initial
144 * pagetables with memblock.
146 memblock_reserve(__pa(_text), _end - _text);
147 #ifdef CONFIG_BLK_DEV_INITRD
149 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start);
152 early_init_fdt_scan_reserved_mem();
154 /* 4GB maximum for 32-bit only capable devices */
155 if (IS_ENABLED(CONFIG_ZONE_DMA))
156 dma_phys_limit = max_zone_dma_phys();
157 dma_contiguous_reserve(dma_phys_limit);
159 memblock_allow_resize();
163 void __init bootmem_init(void)
165 unsigned long min, max;
167 min = PFN_UP(memblock_start_of_DRAM());
168 max = PFN_DOWN(memblock_end_of_DRAM());
171 * Sparsemem tries to allocate bootmem in memory_present(), so must be
172 * done after the fixed reservations.
174 arm64_memory_present();
177 zone_sizes_init(min, max);
179 high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
180 max_pfn = max_low_pfn = max;
183 #ifndef CONFIG_SPARSEMEM_VMEMMAP
184 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
186 struct page *start_pg, *end_pg;
187 unsigned long pg, pgend;
190 * Convert start_pfn/end_pfn to a struct page pointer.
192 start_pg = pfn_to_page(start_pfn - 1) + 1;
193 end_pg = pfn_to_page(end_pfn - 1) + 1;
196 * Convert to physical addresses, and round start upwards and end
199 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
200 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
203 * If there are free pages between these, free the section of the
207 free_bootmem(pg, pgend - pg);
211 * The mem_map array can get very big. Free the unused area of the memory map.
213 static void __init free_unused_memmap(void)
215 unsigned long start, prev_end = 0;
216 struct memblock_region *reg;
218 for_each_memblock(memory, reg) {
219 start = __phys_to_pfn(reg->base);
221 #ifdef CONFIG_SPARSEMEM
223 * Take care not to free memmap entries that don't exist due
224 * to SPARSEMEM sections which aren't present.
226 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
229 * If we had a previous bank, and there is a space between the
230 * current bank and the previous, free it.
232 if (prev_end && prev_end < start)
233 free_memmap(prev_end, start);
236 * Align up here since the VM subsystem insists that the
237 * memmap entries are valid from the bank end aligned to
238 * MAX_ORDER_NR_PAGES.
240 prev_end = ALIGN(start + __phys_to_pfn(reg->size),
244 #ifdef CONFIG_SPARSEMEM
245 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
246 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
249 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
252 * mem_init() marks the free areas in the mem_map and tells us how much memory
253 * is free. This is done after various parts of the system have claimed their
254 * memory after the kernel image.
256 void __init mem_init(void)
258 max_mapnr = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
260 #ifndef CONFIG_SPARSEMEM_VMEMMAP
261 free_unused_memmap();
263 /* this will put all unused low memory onto the freelists */
266 mem_init_print_info(NULL);
268 #define MLK(b, t) b, t, ((t) - (b)) >> 10
269 #define MLM(b, t) b, t, ((t) - (b)) >> 20
270 #define MLG(b, t) b, t, ((t) - (b)) >> 30
271 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
273 pr_notice("Virtual kernel memory layout:\n"
274 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n"
275 #ifdef CONFIG_SPARSEMEM_VMEMMAP
276 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n"
277 " 0x%16lx - 0x%16lx (%6ld MB actual)\n"
279 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n"
280 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n"
281 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
282 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
283 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n"
284 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n"
285 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n",
286 MLG(VMALLOC_START, VMALLOC_END),
287 #ifdef CONFIG_SPARSEMEM_VMEMMAP
288 MLG((unsigned long)vmemmap,
289 (unsigned long)vmemmap + VMEMMAP_SIZE),
290 MLM((unsigned long)virt_to_page(PAGE_OFFSET),
291 (unsigned long)virt_to_page(high_memory)),
293 MLM((unsigned long)PCI_IOBASE, (unsigned long)PCI_IOBASE + SZ_16M),
294 MLK(FIXADDR_START, FIXADDR_TOP),
295 MLM(MODULES_VADDR, MODULES_END),
296 MLM(PAGE_OFFSET, (unsigned long)high_memory),
297 MLK_ROUNDUP(__init_begin, __init_end),
298 MLK_ROUNDUP(_text, _etext),
299 MLK_ROUNDUP(_sdata, _edata));
306 * Check boundaries twice: Some fundamental inconsistencies can be
307 * detected at build time already.
310 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
312 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
313 BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
315 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
316 extern int sysctl_overcommit_memory;
318 * On a machine this small we won't get anywhere without
319 * overcommit, so turn it on by default.
321 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
325 void free_initmem(void)
327 free_initmem_default(0);
330 #ifdef CONFIG_BLK_DEV_INITRD
332 static int keep_initrd;
334 void free_initrd_mem(unsigned long start, unsigned long end)
337 free_reserved_area((void *)start, (void *)end, 0, "initrd");
340 static int __init keepinitrd_setup(char *__unused)
346 __setup("keepinitrd", keepinitrd_setup);