1 /*
2 * arch/xtensa/mm/init.c
3 *
4 * Derived from MIPS, PPC.
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 *
10 * Copyright (C) 2001 - 2005 Tensilica Inc.
11 * Copyright (C) 2014 Cadence Design Systems Inc.
12 *
13 * Chris Zankel <chris@zankel.net>
14 * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
15 * Marc Gauthier
16 * Kevin Chea
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/errno.h>
21 #include <linux/bootmem.h>
22 #include <linux/gfp.h>
23 #include <linux/highmem.h>
24 #include <linux/swap.h>
25 #include <linux/mman.h>
26 #include <linux/nodemask.h>
27 #include <linux/mm.h>
28
29 #include <asm/bootparam.h>
30 #include <asm/page.h>
31 #include <asm/sections.h>
32 #include <asm/sysmem.h>
33
34 struct sysmem_info sysmem __initdata;
35
sysmem_dump(void)36 static void __init sysmem_dump(void)
37 {
38 unsigned i;
39
40 pr_debug("Sysmem:\n");
41 for (i = 0; i < sysmem.nr_banks; ++i)
42 pr_debug(" 0x%08lx - 0x%08lx (%ldK)\n",
43 sysmem.bank[i].start, sysmem.bank[i].end,
44 (sysmem.bank[i].end - sysmem.bank[i].start) >> 10);
45 }
46
47 /*
48 * Find bank with maximal .start such that bank.start <= start
49 */
find_bank(unsigned long start)50 static inline struct meminfo * __init find_bank(unsigned long start)
51 {
52 unsigned i;
53 struct meminfo *it = NULL;
54
55 for (i = 0; i < sysmem.nr_banks; ++i)
56 if (sysmem.bank[i].start <= start)
57 it = sysmem.bank + i;
58 else
59 break;
60 return it;
61 }
62
63 /*
64 * Move all memory banks starting at 'from' to a new place at 'to',
65 * adjust nr_banks accordingly.
66 * Both 'from' and 'to' must be inside the sysmem.bank.
67 *
68 * Returns: 0 (success), -ENOMEM (not enough space in the sysmem.bank).
69 */
move_banks(struct meminfo * to,struct meminfo * from)70 static int __init move_banks(struct meminfo *to, struct meminfo *from)
71 {
72 unsigned n = sysmem.nr_banks - (from - sysmem.bank);
73
74 if (to > from && to - from + sysmem.nr_banks > SYSMEM_BANKS_MAX)
75 return -ENOMEM;
76 if (to != from)
77 memmove(to, from, n * sizeof(struct meminfo));
78 sysmem.nr_banks += to - from;
79 return 0;
80 }
81
82 /*
83 * Add new bank to sysmem. Resulting sysmem is the union of bytes of the
84 * original sysmem and the new bank.
85 *
86 * Returns: 0 (success), < 0 (error)
87 */
add_sysmem_bank(unsigned long start,unsigned long end)88 int __init add_sysmem_bank(unsigned long start, unsigned long end)
89 {
90 unsigned i;
91 struct meminfo *it = NULL;
92 unsigned long sz;
93 unsigned long bank_sz = 0;
94
95 if (start == end ||
96 (start < end) != (PAGE_ALIGN(start) < (end & PAGE_MASK))) {
97 pr_warn("Ignoring small memory bank 0x%08lx size: %ld bytes\n",
98 start, end - start);
99 return -EINVAL;
100 }
101
102 start = PAGE_ALIGN(start);
103 end &= PAGE_MASK;
104 sz = end - start;
105
106 it = find_bank(start);
107
108 if (it)
109 bank_sz = it->end - it->start;
110
111 if (it && bank_sz >= start - it->start) {
112 if (end - it->start > bank_sz)
113 it->end = end;
114 else
115 return 0;
116 } else {
117 if (!it)
118 it = sysmem.bank;
119 else
120 ++it;
121
122 if (it - sysmem.bank < sysmem.nr_banks &&
123 it->start - start <= sz) {
124 it->start = start;
125 if (it->end - it->start < sz)
126 it->end = end;
127 else
128 return 0;
129 } else {
130 if (move_banks(it + 1, it) < 0) {
131 pr_warn("Ignoring memory bank 0x%08lx size %ld bytes\n",
132 start, end - start);
133 return -EINVAL;
134 }
135 it->start = start;
136 it->end = end;
137 return 0;
138 }
139 }
140 sz = it->end - it->start;
141 for (i = it + 1 - sysmem.bank; i < sysmem.nr_banks; ++i)
142 if (sysmem.bank[i].start - it->start <= sz) {
143 if (sz < sysmem.bank[i].end - it->start)
144 it->end = sysmem.bank[i].end;
145 } else {
146 break;
147 }
148
149 move_banks(it + 1, sysmem.bank + i);
150 return 0;
151 }
152
153 /*
154 * mem_reserve(start, end, must_exist)
155 *
156 * Reserve some memory from the memory pool.
157 * If must_exist is set and a part of the region being reserved does not exist
158 * memory map is not altered.
159 *
160 * Parameters:
161 * start Start of region,
162 * end End of region,
163 * must_exist Must exist in memory pool.
164 *
165 * Returns:
166 * 0 (success)
167 * < 0 (error)
168 */
169
mem_reserve(unsigned long start,unsigned long end,int must_exist)170 int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
171 {
172 struct meminfo *it;
173 struct meminfo *rm = NULL;
174 unsigned long sz;
175 unsigned long bank_sz = 0;
176
177 start = start & PAGE_MASK;
178 end = PAGE_ALIGN(end);
179 sz = end - start;
180 if (!sz)
181 return -EINVAL;
182
183 it = find_bank(start);
184
185 if (it)
186 bank_sz = it->end - it->start;
187
188 if ((!it || end - it->start > bank_sz) && must_exist) {
189 pr_warn("mem_reserve: [0x%0lx, 0x%0lx) not in any region!\n",
190 start, end);
191 return -EINVAL;
192 }
193
194 if (it && start - it->start <= bank_sz) {
195 if (start == it->start) {
196 if (end - it->start < bank_sz) {
197 it->start = end;
198 return 0;
199 } else {
200 rm = it;
201 }
202 } else {
203 it->end = start;
204 if (end - it->start < bank_sz)
205 return add_sysmem_bank(end,
206 it->start + bank_sz);
207 ++it;
208 }
209 }
210
211 if (!it)
212 it = sysmem.bank;
213
214 for (; it < sysmem.bank + sysmem.nr_banks; ++it) {
215 if (it->end - start <= sz) {
216 if (!rm)
217 rm = it;
218 } else {
219 if (it->start - start < sz)
220 it->start = end;
221 break;
222 }
223 }
224
225 if (rm)
226 move_banks(rm, it);
227
228 return 0;
229 }
230
231
232 /*
233 * Initialize the bootmem system and give it all low memory we have available.
234 */
235
bootmem_init(void)236 void __init bootmem_init(void)
237 {
238 unsigned long pfn;
239 unsigned long bootmap_start, bootmap_size;
240 int i;
241
242 sysmem_dump();
243 max_low_pfn = max_pfn = 0;
244 min_low_pfn = ~0;
245
246 for (i=0; i < sysmem.nr_banks; i++) {
247 pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT;
248 if (pfn < min_low_pfn)
249 min_low_pfn = pfn;
250 pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT;
251 if (pfn > max_pfn)
252 max_pfn = pfn;
253 }
254
255 if (min_low_pfn > max_pfn)
256 panic("No memory found!\n");
257
258 max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ?
259 max_pfn : MAX_MEM_PFN >> PAGE_SHIFT;
260
261 /* Find an area to use for the bootmem bitmap. */
262
263 bootmap_size = bootmem_bootmap_pages(max_low_pfn - min_low_pfn);
264 bootmap_size <<= PAGE_SHIFT;
265 bootmap_start = ~0;
266
267 for (i=0; i<sysmem.nr_banks; i++)
268 if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) {
269 bootmap_start = sysmem.bank[i].start;
270 break;
271 }
272
273 if (bootmap_start == ~0UL)
274 panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
275
276 /* Reserve the bootmem bitmap area */
277
278 mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1);
279 bootmap_size = init_bootmem_node(NODE_DATA(0),
280 bootmap_start >> PAGE_SHIFT,
281 min_low_pfn,
282 max_low_pfn);
283
284 /* Add all remaining memory pieces into the bootmem map */
285
286 for (i = 0; i < sysmem.nr_banks; i++) {
287 if (sysmem.bank[i].start >> PAGE_SHIFT < max_low_pfn) {
288 unsigned long end = min(max_low_pfn << PAGE_SHIFT,
289 sysmem.bank[i].end);
290 free_bootmem(sysmem.bank[i].start,
291 end - sysmem.bank[i].start);
292 }
293 }
294
295 }
296
297
zones_init(void)298 void __init zones_init(void)
299 {
300 /* All pages are DMA-able, so we put them all in the DMA zone. */
301 unsigned long zones_size[MAX_NR_ZONES] = {
302 [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET,
303 #ifdef CONFIG_HIGHMEM
304 [ZONE_HIGHMEM] = max_pfn - max_low_pfn,
305 #endif
306 };
307 free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
308 }
309
310 /*
311 * Initialize memory pages.
312 */
313
mem_init(void)314 void __init mem_init(void)
315 {
316 #ifdef CONFIG_HIGHMEM
317 unsigned long tmp;
318
319 reset_all_zones_managed_pages();
320 for (tmp = max_low_pfn; tmp < max_pfn; tmp++)
321 free_highmem_page(pfn_to_page(tmp));
322 #endif
323
324 max_mapnr = max_pfn - ARCH_PFN_OFFSET;
325 high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT);
326
327 free_all_bootmem();
328
329 mem_init_print_info(NULL);
330 pr_info("virtual kernel memory layout:\n"
331 #ifdef CONFIG_HIGHMEM
332 " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
333 " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
334 #endif
335 " vmalloc : 0x%08x - 0x%08x (%5u MB)\n"
336 " lowmem : 0x%08x - 0x%08lx (%5lu MB)\n",
337 #ifdef CONFIG_HIGHMEM
338 PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
339 (LAST_PKMAP*PAGE_SIZE) >> 10,
340 FIXADDR_START, FIXADDR_TOP,
341 (FIXADDR_TOP - FIXADDR_START) >> 10,
342 #endif
343 VMALLOC_START, VMALLOC_END,
344 (VMALLOC_END - VMALLOC_START) >> 20,
345 PAGE_OFFSET, PAGE_OFFSET +
346 (max_low_pfn - min_low_pfn) * PAGE_SIZE,
347 ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20);
348 }
349
350 #ifdef CONFIG_BLK_DEV_INITRD
351 extern int initrd_is_mapped;
352
free_initrd_mem(unsigned long start,unsigned long end)353 void free_initrd_mem(unsigned long start, unsigned long end)
354 {
355 if (initrd_is_mapped)
356 free_reserved_area((void *)start, (void *)end, -1, "initrd");
357 }
358 #endif
359
free_initmem(void)360 void free_initmem(void)
361 {
362 free_initmem_default(-1);
363 }
364
parse_memmap_one(char * p)365 static void __init parse_memmap_one(char *p)
366 {
367 char *oldp;
368 unsigned long start_at, mem_size;
369
370 if (!p)
371 return;
372
373 oldp = p;
374 mem_size = memparse(p, &p);
375 if (p == oldp)
376 return;
377
378 switch (*p) {
379 case '@':
380 start_at = memparse(p + 1, &p);
381 add_sysmem_bank(start_at, start_at + mem_size);
382 break;
383
384 case '$':
385 start_at = memparse(p + 1, &p);
386 mem_reserve(start_at, start_at + mem_size, 0);
387 break;
388
389 case 0:
390 mem_reserve(mem_size, 0, 0);
391 break;
392
393 default:
394 pr_warn("Unrecognized memmap syntax: %s\n", p);
395 break;
396 }
397 }
398
parse_memmap_opt(char * str)399 static int __init parse_memmap_opt(char *str)
400 {
401 while (str) {
402 char *k = strchr(str, ',');
403
404 if (k)
405 *k++ = 0;
406
407 parse_memmap_one(str);
408 str = k;
409 }
410
411 return 0;
412 }
413 early_param("memmap", parse_memmap_opt);
414