xref: /openbmc/linux/arch/arm64/mm/init.c (revision cd5d5810)
1 /*
2  * Based on arch/arm/mm/init.c
3  *
4  * Copyright (C) 1995-2005 Russell King
5  * Copyright (C) 2012 ARM Ltd.
6  *
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.
10  *
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.
15  *
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/>.
18  */
19 
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 
34 #include <asm/prom.h>
35 #include <asm/sections.h>
36 #include <asm/setup.h>
37 #include <asm/sizes.h>
38 #include <asm/tlb.h>
39 
40 #include "mm.h"
41 
42 static unsigned long phys_initrd_start __initdata = 0;
43 static unsigned long phys_initrd_size __initdata = 0;
44 
45 phys_addr_t memstart_addr __read_mostly = 0;
46 
47 void __init early_init_dt_setup_initrd_arch(u64 start, u64 end)
48 {
49 	phys_initrd_start = start;
50 	phys_initrd_size = end - start;
51 }
52 
53 static int __init early_initrd(char *p)
54 {
55 	unsigned long start, size;
56 	char *endp;
57 
58 	start = memparse(p, &endp);
59 	if (*endp == ',') {
60 		size = memparse(endp + 1, NULL);
61 
62 		phys_initrd_start = start;
63 		phys_initrd_size = size;
64 	}
65 	return 0;
66 }
67 early_param("initrd", early_initrd);
68 
69 #define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
70 
71 static void __init zone_sizes_init(unsigned long min, unsigned long max)
72 {
73 	struct memblock_region *reg;
74 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
75 	unsigned long max_dma32 = min;
76 
77 	memset(zone_size, 0, sizeof(zone_size));
78 
79 #ifdef CONFIG_ZONE_DMA32
80 	/* 4GB maximum for 32-bit only capable devices */
81 	max_dma32 = max(min, min(max, MAX_DMA32_PFN));
82 	zone_size[ZONE_DMA32] = max_dma32 - min;
83 #endif
84 	zone_size[ZONE_NORMAL] = max - max_dma32;
85 
86 	memcpy(zhole_size, zone_size, sizeof(zhole_size));
87 
88 	for_each_memblock(memory, reg) {
89 		unsigned long start = memblock_region_memory_base_pfn(reg);
90 		unsigned long end = memblock_region_memory_end_pfn(reg);
91 
92 		if (start >= max)
93 			continue;
94 #ifdef CONFIG_ZONE_DMA32
95 		if (start < max_dma32) {
96 			unsigned long dma_end = min(end, max_dma32);
97 			zhole_size[ZONE_DMA32] -= dma_end - start;
98 		}
99 #endif
100 		if (end > max_dma32) {
101 			unsigned long normal_end = min(end, max);
102 			unsigned long normal_start = max(start, max_dma32);
103 			zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
104 		}
105 	}
106 
107 	free_area_init_node(0, zone_size, min, zhole_size);
108 }
109 
110 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
111 int pfn_valid(unsigned long pfn)
112 {
113 	return memblock_is_memory(pfn << PAGE_SHIFT);
114 }
115 EXPORT_SYMBOL(pfn_valid);
116 #endif
117 
118 #ifndef CONFIG_SPARSEMEM
119 static void arm64_memory_present(void)
120 {
121 }
122 #else
123 static void arm64_memory_present(void)
124 {
125 	struct memblock_region *reg;
126 
127 	for_each_memblock(memory, reg)
128 		memory_present(0, memblock_region_memory_base_pfn(reg),
129 			       memblock_region_memory_end_pfn(reg));
130 }
131 #endif
132 
133 void __init arm64_memblock_init(void)
134 {
135 	u64 *reserve_map, base, size;
136 
137 	/* Register the kernel text, kernel data and initrd with memblock */
138 	memblock_reserve(__pa(_text), _end - _text);
139 #ifdef CONFIG_BLK_DEV_INITRD
140 	if (phys_initrd_size) {
141 		memblock_reserve(phys_initrd_start, phys_initrd_size);
142 
143 		/* Now convert initrd to virtual addresses */
144 		initrd_start = __phys_to_virt(phys_initrd_start);
145 		initrd_end = initrd_start + phys_initrd_size;
146 	}
147 #endif
148 
149 	/*
150 	 * Reserve the page tables.  These are already in use,
151 	 * and can only be in node 0.
152 	 */
153 	memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
154 	memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
155 
156 	/* Reserve the dtb region */
157 	memblock_reserve(virt_to_phys(initial_boot_params),
158 			 be32_to_cpu(initial_boot_params->totalsize));
159 
160 	/*
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
164 	 */
165 	reserve_map = ((void*)initial_boot_params) +
166 			be32_to_cpu(initial_boot_params->off_mem_rsvmap);
167 	while (1) {
168 		base = be64_to_cpup(reserve_map++);
169 		size = be64_to_cpup(reserve_map++);
170 		if (!size)
171 			break;
172 		memblock_reserve(base, size);
173 	}
174 
175 	memblock_allow_resize();
176 	memblock_dump_all();
177 }
178 
179 void __init bootmem_init(void)
180 {
181 	unsigned long min, max;
182 
183 	min = PFN_UP(memblock_start_of_DRAM());
184 	max = PFN_DOWN(memblock_end_of_DRAM());
185 
186 	/*
187 	 * Sparsemem tries to allocate bootmem in memory_present(), so must be
188 	 * done after the fixed reservations.
189 	 */
190 	arm64_memory_present();
191 
192 	sparse_init();
193 	zone_sizes_init(min, max);
194 
195 	high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
196 	max_pfn = max_low_pfn = max;
197 }
198 
199 #ifndef CONFIG_SPARSEMEM_VMEMMAP
200 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
201 {
202 	struct page *start_pg, *end_pg;
203 	unsigned long pg, pgend;
204 
205 	/*
206 	 * Convert start_pfn/end_pfn to a struct page pointer.
207 	 */
208 	start_pg = pfn_to_page(start_pfn - 1) + 1;
209 	end_pg = pfn_to_page(end_pfn - 1) + 1;
210 
211 	/*
212 	 * Convert to physical addresses, and round start upwards and end
213 	 * downwards.
214 	 */
215 	pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
216 	pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
217 
218 	/*
219 	 * If there are free pages between these, free the section of the
220 	 * memmap array.
221 	 */
222 	if (pg < pgend)
223 		free_bootmem(pg, pgend - pg);
224 }
225 
226 /*
227  * The mem_map array can get very big. Free the unused area of the memory map.
228  */
229 static void __init free_unused_memmap(void)
230 {
231 	unsigned long start, prev_end = 0;
232 	struct memblock_region *reg;
233 
234 	for_each_memblock(memory, reg) {
235 		start = __phys_to_pfn(reg->base);
236 
237 #ifdef CONFIG_SPARSEMEM
238 		/*
239 		 * Take care not to free memmap entries that don't exist due
240 		 * to SPARSEMEM sections which aren't present.
241 		 */
242 		start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
243 #endif
244 		/*
245 		 * If we had a previous bank, and there is a space between the
246 		 * current bank and the previous, free it.
247 		 */
248 		if (prev_end && prev_end < start)
249 			free_memmap(prev_end, start);
250 
251 		/*
252 		 * Align up here since the VM subsystem insists that the
253 		 * memmap entries are valid from the bank end aligned to
254 		 * MAX_ORDER_NR_PAGES.
255 		 */
256 		prev_end = ALIGN(start + __phys_to_pfn(reg->size),
257 				 MAX_ORDER_NR_PAGES);
258 	}
259 
260 #ifdef CONFIG_SPARSEMEM
261 	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
262 		free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
263 #endif
264 }
265 #endif	/* !CONFIG_SPARSEMEM_VMEMMAP */
266 
267 /*
268  * mem_init() marks the free areas in the mem_map and tells us how much memory
269  * is free.  This is done after various parts of the system have claimed their
270  * memory after the kernel image.
271  */
272 void __init mem_init(void)
273 {
274 	arm64_swiotlb_init();
275 
276 	max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
277 
278 #ifndef CONFIG_SPARSEMEM_VMEMMAP
279 	free_unused_memmap();
280 #endif
281 	/* this will put all unused low memory onto the freelists */
282 	free_all_bootmem();
283 
284 	mem_init_print_info(NULL);
285 
286 #define MLK(b, t) b, t, ((t) - (b)) >> 10
287 #define MLM(b, t) b, t, ((t) - (b)) >> 20
288 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
289 
290 	pr_notice("Virtual kernel memory layout:\n"
291 		  "    vmalloc : 0x%16lx - 0x%16lx   (%6ld MB)\n"
292 #ifdef CONFIG_SPARSEMEM_VMEMMAP
293 		  "    vmemmap : 0x%16lx - 0x%16lx   (%6ld MB)\n"
294 #endif
295 		  "    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n"
296 		  "    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n"
297 		  "      .init : 0x%p" " - 0x%p" "   (%6ld kB)\n"
298 		  "      .text : 0x%p" " - 0x%p" "   (%6ld kB)\n"
299 		  "      .data : 0x%p" " - 0x%p" "   (%6ld kB)\n",
300 		  MLM(VMALLOC_START, VMALLOC_END),
301 #ifdef CONFIG_SPARSEMEM_VMEMMAP
302 		  MLM((unsigned long)virt_to_page(PAGE_OFFSET),
303 		      (unsigned long)virt_to_page(high_memory)),
304 #endif
305 		  MLM(MODULES_VADDR, MODULES_END),
306 		  MLM(PAGE_OFFSET, (unsigned long)high_memory),
307 
308 		  MLK_ROUNDUP(__init_begin, __init_end),
309 		  MLK_ROUNDUP(_text, _etext),
310 		  MLK_ROUNDUP(_sdata, _edata));
311 
312 #undef MLK
313 #undef MLM
314 #undef MLK_ROUNDUP
315 
316 	/*
317 	 * Check boundaries twice: Some fundamental inconsistencies can be
318 	 * detected at build time already.
319 	 */
320 #ifdef CONFIG_COMPAT
321 	BUILD_BUG_ON(TASK_SIZE_32			> TASK_SIZE_64);
322 #endif
323 	BUILD_BUG_ON(TASK_SIZE_64			> MODULES_VADDR);
324 	BUG_ON(TASK_SIZE_64				> MODULES_VADDR);
325 
326 	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
327 		extern int sysctl_overcommit_memory;
328 		/*
329 		 * On a machine this small we won't get anywhere without
330 		 * overcommit, so turn it on by default.
331 		 */
332 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
333 	}
334 }
335 
336 void free_initmem(void)
337 {
338 	free_initmem_default(0);
339 }
340 
341 #ifdef CONFIG_BLK_DEV_INITRD
342 
343 static int keep_initrd;
344 
345 void free_initrd_mem(unsigned long start, unsigned long end)
346 {
347 	if (!keep_initrd)
348 		free_reserved_area((void *)start, (void *)end, 0, "initrd");
349 }
350 
351 static int __init keepinitrd_setup(char *__unused)
352 {
353 	keep_initrd = 1;
354 	return 1;
355 }
356 
357 __setup("keepinitrd", keepinitrd_setup);
358 #endif
359