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/fixmap.h>
37 #include <asm/sections.h>
38 #include <asm/setup.h>
39 #include <asm/sizes.h>
44 phys_addr_t memstart_addr __read_mostly
= 0;
46 #ifdef CONFIG_BLK_DEV_INITRD
47 static int __init
early_initrd(char *p
)
49 unsigned long start
, size
;
52 start
= memparse(p
, &endp
);
54 size
= memparse(endp
+ 1, NULL
);
56 initrd_start
= (unsigned long)__va(start
);
57 initrd_end
= (unsigned long)__va(start
+ size
);
61 early_param("initrd", early_initrd
);
65 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
66 * currently assumes that for memory starting above 4G, 32-bit devices will
69 static phys_addr_t
max_zone_dma_phys(void)
71 phys_addr_t offset
= memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
72 return min(offset
+ (1ULL << 32), memblock_end_of_DRAM());
75 static void __init
zone_sizes_init(unsigned long min
, unsigned long max
)
77 struct memblock_region
*reg
;
78 unsigned long zone_size
[MAX_NR_ZONES
], zhole_size
[MAX_NR_ZONES
];
79 unsigned long max_dma
= min
;
81 memset(zone_size
, 0, sizeof(zone_size
));
83 /* 4GB maximum for 32-bit only capable devices */
84 if (IS_ENABLED(CONFIG_ZONE_DMA
)) {
85 max_dma
= PFN_DOWN(max_zone_dma_phys());
86 zone_size
[ZONE_DMA
] = max_dma
- min
;
88 zone_size
[ZONE_NORMAL
] = max
- max_dma
;
90 memcpy(zhole_size
, zone_size
, sizeof(zhole_size
));
92 for_each_memblock(memory
, reg
) {
93 unsigned long start
= memblock_region_memory_base_pfn(reg
);
94 unsigned long end
= memblock_region_memory_end_pfn(reg
);
99 if (IS_ENABLED(CONFIG_ZONE_DMA
) && start
< max_dma
) {
100 unsigned long dma_end
= min(end
, max_dma
);
101 zhole_size
[ZONE_DMA
] -= dma_end
- start
;
105 unsigned long normal_end
= min(end
, max
);
106 unsigned long normal_start
= max(start
, max_dma
);
107 zhole_size
[ZONE_NORMAL
] -= normal_end
- normal_start
;
111 free_area_init_node(0, zone_size
, min
, zhole_size
);
114 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
115 int pfn_valid(unsigned long pfn
)
117 return 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 phys_addr_t dma_phys_limit
= 0;
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
148 memblock_reserve(__virt_to_phys(initrd_start
), initrd_end
- initrd_start
);
151 early_init_fdt_scan_reserved_mem();
153 /* 4GB maximum for 32-bit only capable devices */
154 if (IS_ENABLED(CONFIG_ZONE_DMA
))
155 dma_phys_limit
= max_zone_dma_phys();
156 dma_contiguous_reserve(dma_phys_limit
);
158 memblock_allow_resize();
162 void __init
bootmem_init(void)
164 unsigned long min
, max
;
166 min
= PFN_UP(memblock_start_of_DRAM());
167 max
= PFN_DOWN(memblock_end_of_DRAM());
170 * Sparsemem tries to allocate bootmem in memory_present(), so must be
171 * done after the fixed reservations.
173 arm64_memory_present();
176 zone_sizes_init(min
, max
);
178 high_memory
= __va((max
<< PAGE_SHIFT
) - 1) + 1;
179 max_pfn
= max_low_pfn
= max
;
182 #ifndef CONFIG_SPARSEMEM_VMEMMAP
183 static inline void free_memmap(unsigned long start_pfn
, unsigned long end_pfn
)
185 struct page
*start_pg
, *end_pg
;
186 unsigned long pg
, pgend
;
189 * Convert start_pfn/end_pfn to a struct page pointer.
191 start_pg
= pfn_to_page(start_pfn
- 1) + 1;
192 end_pg
= pfn_to_page(end_pfn
- 1) + 1;
195 * Convert to physical addresses, and round start upwards and end
198 pg
= (unsigned long)PAGE_ALIGN(__pa(start_pg
));
199 pgend
= (unsigned long)__pa(end_pg
) & PAGE_MASK
;
202 * If there are free pages between these, free the section of the
206 free_bootmem(pg
, pgend
- pg
);
210 * The mem_map array can get very big. Free the unused area of the memory map.
212 static void __init
free_unused_memmap(void)
214 unsigned long start
, prev_end
= 0;
215 struct memblock_region
*reg
;
217 for_each_memblock(memory
, reg
) {
218 start
= __phys_to_pfn(reg
->base
);
220 #ifdef CONFIG_SPARSEMEM
222 * Take care not to free memmap entries that don't exist due
223 * to SPARSEMEM sections which aren't present.
225 start
= min(start
, ALIGN(prev_end
, PAGES_PER_SECTION
));
228 * If we had a previous bank, and there is a space between the
229 * current bank and the previous, free it.
231 if (prev_end
&& prev_end
< start
)
232 free_memmap(prev_end
, start
);
235 * Align up here since the VM subsystem insists that the
236 * memmap entries are valid from the bank end aligned to
237 * MAX_ORDER_NR_PAGES.
239 prev_end
= ALIGN(start
+ __phys_to_pfn(reg
->size
),
243 #ifdef CONFIG_SPARSEMEM
244 if (!IS_ALIGNED(prev_end
, PAGES_PER_SECTION
))
245 free_memmap(prev_end
, ALIGN(prev_end
, PAGES_PER_SECTION
));
248 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
251 * mem_init() marks the free areas in the mem_map and tells us how much memory
252 * is free. This is done after various parts of the system have claimed their
253 * memory after the kernel image.
255 void __init
mem_init(void)
257 max_mapnr
= pfn_to_page(max_pfn
+ PHYS_PFN_OFFSET
) - mem_map
;
259 #ifndef CONFIG_SPARSEMEM_VMEMMAP
260 free_unused_memmap();
262 /* this will put all unused low memory onto the freelists */
265 mem_init_print_info(NULL
);
267 #define MLK(b, t) b, t, ((t) - (b)) >> 10
268 #define MLM(b, t) b, t, ((t) - (b)) >> 20
269 #define MLG(b, t) b, t, ((t) - (b)) >> 30
270 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
272 pr_notice("Virtual kernel memory layout:\n"
273 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n"
274 #ifdef CONFIG_SPARSEMEM_VMEMMAP
275 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n"
276 " 0x%16lx - 0x%16lx (%6ld MB actual)\n"
278 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n"
279 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n"
280 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
281 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
282 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n"
283 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n"
284 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n",
285 MLG(VMALLOC_START
, VMALLOC_END
),
286 #ifdef CONFIG_SPARSEMEM_VMEMMAP
287 MLG((unsigned long)vmemmap
,
288 (unsigned long)vmemmap
+ VMEMMAP_SIZE
),
289 MLM((unsigned long)virt_to_page(PAGE_OFFSET
),
290 (unsigned long)virt_to_page(high_memory
)),
292 MLM((unsigned long)PCI_IOBASE
, (unsigned long)PCI_IOBASE
+ SZ_16M
),
293 MLK(FIXADDR_START
, FIXADDR_TOP
),
294 MLM(MODULES_VADDR
, MODULES_END
),
295 MLM(PAGE_OFFSET
, (unsigned long)high_memory
),
296 MLK_ROUNDUP(__init_begin
, __init_end
),
297 MLK_ROUNDUP(_text
, _etext
),
298 MLK_ROUNDUP(_sdata
, _edata
));
305 * Check boundaries twice: Some fundamental inconsistencies can be
306 * detected at build time already.
309 BUILD_BUG_ON(TASK_SIZE_32
> TASK_SIZE_64
);
311 BUILD_BUG_ON(TASK_SIZE_64
> MODULES_VADDR
);
312 BUG_ON(TASK_SIZE_64
> MODULES_VADDR
);
314 if (PAGE_SIZE
>= 16384 && get_num_physpages() <= 128) {
315 extern int sysctl_overcommit_memory
;
317 * On a machine this small we won't get anywhere without
318 * overcommit, so turn it on by default.
320 sysctl_overcommit_memory
= OVERCOMMIT_ALWAYS
;
324 void free_initmem(void)
326 free_initmem_default(0);
329 #ifdef CONFIG_BLK_DEV_INITRD
331 static int keep_initrd
;
333 void free_initrd_mem(unsigned long start
, unsigned long end
)
336 free_reserved_area((void *)start
, (void *)end
, 0, "initrd");
339 static int __init
keepinitrd_setup(char *__unused
)
345 __setup("keepinitrd", keepinitrd_setup
);