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>
36 #include <asm/sections.h>
37 #include <asm/setup.h>
38 #include <asm/sizes.h>
43 phys_addr_t memstart_addr __read_mostly
= 0;
45 #ifdef CONFIG_BLK_DEV_INITRD
46 static int __init
early_initrd(char *p
)
48 unsigned long start
, size
;
51 start
= memparse(p
, &endp
);
53 size
= memparse(endp
+ 1, NULL
);
55 initrd_start
= (unsigned long)__va(start
);
56 initrd_end
= (unsigned long)__va(start
+ size
);
60 early_param("initrd", early_initrd
);
63 static void __init
zone_sizes_init(unsigned long min
, unsigned long max
)
65 struct memblock_region
*reg
;
66 unsigned long zone_size
[MAX_NR_ZONES
], zhole_size
[MAX_NR_ZONES
];
67 unsigned long max_dma
= min
;
69 memset(zone_size
, 0, sizeof(zone_size
));
71 /* 4GB maximum for 32-bit only capable devices */
72 if (IS_ENABLED(CONFIG_ZONE_DMA
)) {
73 unsigned long max_dma_phys
=
74 (unsigned long)(dma_to_phys(NULL
, DMA_BIT_MASK(32)) + 1);
75 max_dma
= max(min
, min(max
, max_dma_phys
>> PAGE_SHIFT
));
76 zone_size
[ZONE_DMA
] = max_dma
- min
;
78 zone_size
[ZONE_NORMAL
] = max
- max_dma
;
80 memcpy(zhole_size
, zone_size
, sizeof(zhole_size
));
82 for_each_memblock(memory
, reg
) {
83 unsigned long start
= memblock_region_memory_base_pfn(reg
);
84 unsigned long end
= memblock_region_memory_end_pfn(reg
);
89 if (IS_ENABLED(CONFIG_ZONE_DMA
) && start
< max_dma
) {
90 unsigned long dma_end
= min(end
, max_dma
);
91 zhole_size
[ZONE_DMA
] -= dma_end
- start
;
95 unsigned long normal_end
= min(end
, max
);
96 unsigned long normal_start
= max(start
, max_dma
);
97 zhole_size
[ZONE_NORMAL
] -= normal_end
- normal_start
;
101 free_area_init_node(0, zone_size
, min
, zhole_size
);
104 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
105 int pfn_valid(unsigned long pfn
)
107 return memblock_is_memory(pfn
<< PAGE_SHIFT
);
109 EXPORT_SYMBOL(pfn_valid
);
112 #ifndef CONFIG_SPARSEMEM
113 static void arm64_memory_present(void)
117 static void arm64_memory_present(void)
119 struct memblock_region
*reg
;
121 for_each_memblock(memory
, reg
)
122 memory_present(0, memblock_region_memory_base_pfn(reg
),
123 memblock_region_memory_end_pfn(reg
));
127 void __init
arm64_memblock_init(void)
129 phys_addr_t dma_phys_limit
= 0;
131 /* Register the kernel text, kernel data and initrd with memblock */
132 memblock_reserve(__pa(_text
), _end
- _text
);
133 #ifdef CONFIG_BLK_DEV_INITRD
135 memblock_reserve(__virt_to_phys(initrd_start
), initrd_end
- initrd_start
);
139 * Reserve the page tables. These are already in use,
140 * and can only be in node 0.
142 memblock_reserve(__pa(swapper_pg_dir
), SWAPPER_DIR_SIZE
);
143 memblock_reserve(__pa(idmap_pg_dir
), IDMAP_DIR_SIZE
);
145 early_init_fdt_scan_reserved_mem();
147 /* 4GB maximum for 32-bit only capable devices */
148 if (IS_ENABLED(CONFIG_ZONE_DMA
))
149 dma_phys_limit
= dma_to_phys(NULL
, DMA_BIT_MASK(32)) + 1;
150 dma_contiguous_reserve(dma_phys_limit
);
152 memblock_allow_resize();
156 void __init
bootmem_init(void)
158 unsigned long min
, max
;
160 min
= PFN_UP(memblock_start_of_DRAM());
161 max
= PFN_DOWN(memblock_end_of_DRAM());
164 * Sparsemem tries to allocate bootmem in memory_present(), so must be
165 * done after the fixed reservations.
167 arm64_memory_present();
170 zone_sizes_init(min
, max
);
172 high_memory
= __va((max
<< PAGE_SHIFT
) - 1) + 1;
173 max_pfn
= max_low_pfn
= max
;
176 #ifndef CONFIG_SPARSEMEM_VMEMMAP
177 static inline void free_memmap(unsigned long start_pfn
, unsigned long end_pfn
)
179 struct page
*start_pg
, *end_pg
;
180 unsigned long pg
, pgend
;
183 * Convert start_pfn/end_pfn to a struct page pointer.
185 start_pg
= pfn_to_page(start_pfn
- 1) + 1;
186 end_pg
= pfn_to_page(end_pfn
- 1) + 1;
189 * Convert to physical addresses, and round start upwards and end
192 pg
= (unsigned long)PAGE_ALIGN(__pa(start_pg
));
193 pgend
= (unsigned long)__pa(end_pg
) & PAGE_MASK
;
196 * If there are free pages between these, free the section of the
200 free_bootmem(pg
, pgend
- pg
);
204 * The mem_map array can get very big. Free the unused area of the memory map.
206 static void __init
free_unused_memmap(void)
208 unsigned long start
, prev_end
= 0;
209 struct memblock_region
*reg
;
211 for_each_memblock(memory
, reg
) {
212 start
= __phys_to_pfn(reg
->base
);
214 #ifdef CONFIG_SPARSEMEM
216 * Take care not to free memmap entries that don't exist due
217 * to SPARSEMEM sections which aren't present.
219 start
= min(start
, ALIGN(prev_end
, PAGES_PER_SECTION
));
222 * If we had a previous bank, and there is a space between the
223 * current bank and the previous, free it.
225 if (prev_end
&& prev_end
< start
)
226 free_memmap(prev_end
, start
);
229 * Align up here since the VM subsystem insists that the
230 * memmap entries are valid from the bank end aligned to
231 * MAX_ORDER_NR_PAGES.
233 prev_end
= ALIGN(start
+ __phys_to_pfn(reg
->size
),
237 #ifdef CONFIG_SPARSEMEM
238 if (!IS_ALIGNED(prev_end
, PAGES_PER_SECTION
))
239 free_memmap(prev_end
, ALIGN(prev_end
, PAGES_PER_SECTION
));
242 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
245 * mem_init() marks the free areas in the mem_map and tells us how much memory
246 * is free. This is done after various parts of the system have claimed their
247 * memory after the kernel image.
249 void __init
mem_init(void)
251 max_mapnr
= pfn_to_page(max_pfn
+ PHYS_PFN_OFFSET
) - mem_map
;
253 #ifndef CONFIG_SPARSEMEM_VMEMMAP
254 free_unused_memmap();
256 /* this will put all unused low memory onto the freelists */
259 mem_init_print_info(NULL
);
261 #define MLK(b, t) b, t, ((t) - (b)) >> 10
262 #define MLM(b, t) b, t, ((t) - (b)) >> 20
263 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
265 pr_notice("Virtual kernel memory layout:\n"
266 " vmalloc : 0x%16lx - 0x%16lx (%6ld MB)\n"
267 #ifdef CONFIG_SPARSEMEM_VMEMMAP
268 " vmemmap : 0x%16lx - 0x%16lx (%6ld MB)\n"
270 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
271 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
272 " .init : 0x%p" " - 0x%p" " (%6ld kB)\n"
273 " .text : 0x%p" " - 0x%p" " (%6ld kB)\n"
274 " .data : 0x%p" " - 0x%p" " (%6ld kB)\n",
275 MLM(VMALLOC_START
, VMALLOC_END
),
276 #ifdef CONFIG_SPARSEMEM_VMEMMAP
277 MLM((unsigned long)virt_to_page(PAGE_OFFSET
),
278 (unsigned long)virt_to_page(high_memory
)),
280 MLM(MODULES_VADDR
, MODULES_END
),
281 MLM(PAGE_OFFSET
, (unsigned long)high_memory
),
283 MLK_ROUNDUP(__init_begin
, __init_end
),
284 MLK_ROUNDUP(_text
, _etext
),
285 MLK_ROUNDUP(_sdata
, _edata
));
292 * Check boundaries twice: Some fundamental inconsistencies can be
293 * detected at build time already.
296 BUILD_BUG_ON(TASK_SIZE_32
> TASK_SIZE_64
);
298 BUILD_BUG_ON(TASK_SIZE_64
> MODULES_VADDR
);
299 BUG_ON(TASK_SIZE_64
> MODULES_VADDR
);
301 if (PAGE_SIZE
>= 16384 && get_num_physpages() <= 128) {
302 extern int sysctl_overcommit_memory
;
304 * On a machine this small we won't get anywhere without
305 * overcommit, so turn it on by default.
307 sysctl_overcommit_memory
= OVERCOMMIT_ALWAYS
;
311 void free_initmem(void)
313 free_initmem_default(0);
316 #ifdef CONFIG_BLK_DEV_INITRD
318 static int keep_initrd
;
320 void free_initrd_mem(unsigned long start
, unsigned long end
)
323 free_reserved_area((void *)start
, (void *)end
, 0, "initrd");
326 static int __init
keepinitrd_setup(char *__unused
)
332 __setup("keepinitrd", keepinitrd_setup
);