1 /*
2 * Procedures for maintaining information about logical memory blocks.
3 *
4 * Peter Bergner, IBM Corp. June 2001.
5 * Copyright (C) 2001 Peter Bergner.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/bitops.h>
16 #include <linux/lmb.h>
17
18 #define LMB_ALLOC_ANYWHERE 0
19
20 struct lmb lmb;
21
22 static int lmb_debug;
23
24 static int __init early_lmb(char *p)
25 {
26 if (p && strstr(p, "debug"))
27 lmb_debug = 1;
28 return 0;
29 }
30 early_param("lmb", early_lmb);
31
32 static void lmb_dump(struct lmb_region *region, char *name)
33 {
34 unsigned long long base, size;
35 int i;
36
37 pr_info(" %s.cnt = 0x%lx\n", name, region->cnt);
38
39 for (i = 0; i < region->cnt; i++) {
40 base = region->region[i].base;
41 size = region->region[i].size;
42
43 pr_info(" %s[0x%x]\t0x%016llx - 0x%016llx, 0x%llx bytes\n",
44 name, i, base, base + size - 1, size);
45 }
46 }
47
48 void lmb_dump_all(void)
49 {
50 if (!lmb_debug)
51 return;
52
53 pr_info("LMB configuration:\n");
54 pr_info(" rmo_size = 0x%llx\n", (unsigned long long)lmb.rmo_size);
55 pr_info(" memory.size = 0x%llx\n", (unsigned long long)lmb.memory.size);
56
57 lmb_dump(&lmb.memory, "memory");
58 lmb_dump(&lmb.reserved, "reserved");
59 }
60
61 static unsigned long lmb_addrs_overlap(u64 base1, u64 size1, u64 base2,
62 u64 size2)
63 {
64 return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
65 }
66
67 static long lmb_addrs_adjacent(u64 base1, u64 size1, u64 base2, u64 size2)
68 {
69 if (base2 == base1 + size1)
70 return 1;
71 else if (base1 == base2 + size2)
72 return -1;
73
74 return 0;
75 }
76
77 static long lmb_regions_adjacent(struct lmb_region *rgn,
78 unsigned long r1, unsigned long r2)
79 {
80 u64 base1 = rgn->region[r1].base;
81 u64 size1 = rgn->region[r1].size;
82 u64 base2 = rgn->region[r2].base;
83 u64 size2 = rgn->region[r2].size;
84
85 return lmb_addrs_adjacent(base1, size1, base2, size2);
86 }
87
88 static void lmb_remove_region(struct lmb_region *rgn, unsigned long r)
89 {
90 unsigned long i;
91
92 for (i = r; i < rgn->cnt - 1; i++) {
93 rgn->region[i].base = rgn->region[i + 1].base;
94 rgn->region[i].size = rgn->region[i + 1].size;
95 }
96 rgn->cnt--;
97 }
98
99 /* Assumption: base addr of region 1 < base addr of region 2 */
100 static void lmb_coalesce_regions(struct lmb_region *rgn,
101 unsigned long r1, unsigned long r2)
102 {
103 rgn->region[r1].size += rgn->region[r2].size;
104 lmb_remove_region(rgn, r2);
105 }
106
107 void __init lmb_init(void)
108 {
109 /* Create a dummy zero size LMB which will get coalesced away later.
110 * This simplifies the lmb_add() code below...
111 */
112 lmb.memory.region[0].base = 0;
113 lmb.memory.region[0].size = 0;
114 lmb.memory.cnt = 1;
115
116 /* Ditto. */
117 lmb.reserved.region[0].base = 0;
118 lmb.reserved.region[0].size = 0;
119 lmb.reserved.cnt = 1;
120 }
121
122 void __init lmb_analyze(void)
123 {
124 int i;
125
126 lmb.memory.size = 0;
127
128 for (i = 0; i < lmb.memory.cnt; i++)
129 lmb.memory.size += lmb.memory.region[i].size;
130 }
131
132 static long lmb_add_region(struct lmb_region *rgn, u64 base, u64 size)
133 {
134 unsigned long coalesced = 0;
135 long adjacent, i;
136
137 if ((rgn->cnt == 1) && (rgn->region[0].size == 0)) {
138 rgn->region[0].base = base;
139 rgn->region[0].size = size;
140 return 0;
141 }
142
143 /* First try and coalesce this LMB with another. */
144 for (i = 0; i < rgn->cnt; i++) {
145 u64 rgnbase = rgn->region[i].base;
146 u64 rgnsize = rgn->region[i].size;
147
148 if ((rgnbase == base) && (rgnsize == size))
149 /* Already have this region, so we're done */
150 return 0;
151
152 adjacent = lmb_addrs_adjacent(base, size, rgnbase, rgnsize);
153 if (adjacent > 0) {
154 rgn->region[i].base -= size;
155 rgn->region[i].size += size;
156 coalesced++;
157 break;
158 } else if (adjacent < 0) {
159 rgn->region[i].size += size;
160 coalesced++;
161 break;
162 }
163 }
164
165 if ((i < rgn->cnt - 1) && lmb_regions_adjacent(rgn, i, i+1)) {
166 lmb_coalesce_regions(rgn, i, i+1);
167 coalesced++;
168 }
169
170 if (coalesced)
171 return coalesced;
172 if (rgn->cnt >= MAX_LMB_REGIONS)
173 return -1;
174
175 /* Couldn't coalesce the LMB, so add it to the sorted table. */
176 for (i = rgn->cnt - 1; i >= 0; i--) {
177 if (base < rgn->region[i].base) {
178 rgn->region[i+1].base = rgn->region[i].base;
179 rgn->region[i+1].size = rgn->region[i].size;
180 } else {
181 rgn->region[i+1].base = base;
182 rgn->region[i+1].size = size;
183 break;
184 }
185 }
186
187 if (base < rgn->region[0].base) {
188 rgn->region[0].base = base;
189 rgn->region[0].size = size;
190 }
191 rgn->cnt++;
192
193 return 0;
194 }
195
196 long lmb_add(u64 base, u64 size)
197 {
198 struct lmb_region *_rgn = &lmb.memory;
199
200 /* On pSeries LPAR systems, the first LMB is our RMO region. */
201 if (base == 0)
202 lmb.rmo_size = size;
203
204 return lmb_add_region(_rgn, base, size);
205
206 }
207
208 long lmb_remove(u64 base, u64 size)
209 {
210 struct lmb_region *rgn = &(lmb.memory);
211 u64 rgnbegin, rgnend;
212 u64 end = base + size;
213 int i;
214
215 rgnbegin = rgnend = 0; /* supress gcc warnings */
216
217 /* Find the region where (base, size) belongs to */
218 for (i=0; i < rgn->cnt; i++) {
219 rgnbegin = rgn->region[i].base;
220 rgnend = rgnbegin + rgn->region[i].size;
221
222 if ((rgnbegin <= base) && (end <= rgnend))
223 break;
224 }
225
226 /* Didn't find the region */
227 if (i == rgn->cnt)
228 return -1;
229
230 /* Check to see if we are removing entire region */
231 if ((rgnbegin == base) && (rgnend == end)) {
232 lmb_remove_region(rgn, i);
233 return 0;
234 }
235
236 /* Check to see if region is matching at the front */
237 if (rgnbegin == base) {
238 rgn->region[i].base = end;
239 rgn->region[i].size -= size;
240 return 0;
241 }
242
243 /* Check to see if the region is matching at the end */
244 if (rgnend == end) {
245 rgn->region[i].size -= size;
246 return 0;
247 }
248
249 /*
250 * We need to split the entry - adjust the current one to the
251 * beginging of the hole and add the region after hole.
252 */
253 rgn->region[i].size = base - rgn->region[i].base;
254 return lmb_add_region(rgn, end, rgnend - end);
255 }
256
257 long __init lmb_reserve(u64 base, u64 size)
258 {
259 struct lmb_region *_rgn = &lmb.reserved;
260
261 BUG_ON(0 == size);
262
263 return lmb_add_region(_rgn, base, size);
264 }
265
266 long __init lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)
267 {
268 unsigned long i;
269
270 for (i = 0; i < rgn->cnt; i++) {
271 u64 rgnbase = rgn->region[i].base;
272 u64 rgnsize = rgn->region[i].size;
273 if (lmb_addrs_overlap(base, size, rgnbase, rgnsize))
274 break;
275 }
276
277 return (i < rgn->cnt) ? i : -1;
278 }
279
280 static u64 lmb_align_down(u64 addr, u64 size)
281 {
282 return addr & ~(size - 1);
283 }
284
285 static u64 lmb_align_up(u64 addr, u64 size)
286 {
287 return (addr + (size - 1)) & ~(size - 1);
288 }
289
290 static u64 __init lmb_alloc_nid_unreserved(u64 start, u64 end,
291 u64 size, u64 align)
292 {
293 u64 base, res_base;
294 long j;
295
296 base = lmb_align_down((end - size), align);
297 while (start <= base) {
298 j = lmb_overlaps_region(&lmb.reserved, base, size);
299 if (j < 0) {
300 /* this area isn't reserved, take it */
301 if (lmb_add_region(&lmb.reserved, base, size) < 0)
302 base = ~(u64)0;
303 return base;
304 }
305 res_base = lmb.reserved.region[j].base;
306 if (res_base < size)
307 break;
308 base = lmb_align_down(res_base - size, align);
309 }
310
311 return ~(u64)0;
312 }
313
314 static u64 __init lmb_alloc_nid_region(struct lmb_property *mp,
315 u64 (*nid_range)(u64, u64, int *),
316 u64 size, u64 align, int nid)
317 {
318 u64 start, end;
319
320 start = mp->base;
321 end = start + mp->size;
322
323 start = lmb_align_up(start, align);
324 while (start < end) {
325 u64 this_end;
326 int this_nid;
327
328 this_end = nid_range(start, end, &this_nid);
329 if (this_nid == nid) {
330 u64 ret = lmb_alloc_nid_unreserved(start, this_end,
331 size, align);
332 if (ret != ~(u64)0)
333 return ret;
334 }
335 start = this_end;
336 }
337
338 return ~(u64)0;
339 }
340
341 u64 __init lmb_alloc_nid(u64 size, u64 align, int nid,
342 u64 (*nid_range)(u64 start, u64 end, int *nid))
343 {
344 struct lmb_region *mem = &lmb.memory;
345 int i;
346
347 BUG_ON(0 == size);
348
349 size = lmb_align_up(size, align);
350
351 for (i = 0; i < mem->cnt; i++) {
352 u64 ret = lmb_alloc_nid_region(&mem->region[i],
353 nid_range,
354 size, align, nid);
355 if (ret != ~(u64)0)
356 return ret;
357 }
358
359 return lmb_alloc(size, align);
360 }
361
362 u64 __init lmb_alloc(u64 size, u64 align)
363 {
364 return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
365 }
366
367 u64 __init lmb_alloc_base(u64 size, u64 align, u64 max_addr)
368 {
369 u64 alloc;
370
371 alloc = __lmb_alloc_base(size, align, max_addr);
372
373 if (alloc == 0)
374 panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
375 (unsigned long long) size, (unsigned long long) max_addr);
376
377 return alloc;
378 }
379
380 u64 __init __lmb_alloc_base(u64 size, u64 align, u64 max_addr)
381 {
382 long i, j;
383 u64 base = 0;
384 u64 res_base;
385
386 BUG_ON(0 == size);
387
388 size = lmb_align_up(size, align);
389
390 /* On some platforms, make sure we allocate lowmem */
391 /* Note that LMB_REAL_LIMIT may be LMB_ALLOC_ANYWHERE */
392 if (max_addr == LMB_ALLOC_ANYWHERE)
393 max_addr = LMB_REAL_LIMIT;
394
395 for (i = lmb.memory.cnt - 1; i >= 0; i--) {
396 u64 lmbbase = lmb.memory.region[i].base;
397 u64 lmbsize = lmb.memory.region[i].size;
398
399 if (lmbsize < size)
400 continue;
401 if (max_addr == LMB_ALLOC_ANYWHERE)
402 base = lmb_align_down(lmbbase + lmbsize - size, align);
403 else if (lmbbase < max_addr) {
404 base = min(lmbbase + lmbsize, max_addr);
405 base = lmb_align_down(base - size, align);
406 } else
407 continue;
408
409 while (base && lmbbase <= base) {
410 j = lmb_overlaps_region(&lmb.reserved, base, size);
411 if (j < 0) {
412 /* this area isn't reserved, take it */
413 if (lmb_add_region(&lmb.reserved, base, size) < 0)
414 return 0;
415 return base;
416 }
417 res_base = lmb.reserved.region[j].base;
418 if (res_base < size)
419 break;
420 base = lmb_align_down(res_base - size, align);
421 }
422 }
423 return 0;
424 }
425
426 /* You must call lmb_analyze() before this. */
427 u64 __init lmb_phys_mem_size(void)
428 {
429 return lmb.memory.size;
430 }
431
432 u64 lmb_end_of_DRAM(void)
433 {
434 int idx = lmb.memory.cnt - 1;
435
436 return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
437 }
438
439 /* You must call lmb_analyze() after this. */
440 void __init lmb_enforce_memory_limit(u64 memory_limit)
441 {
442 unsigned long i;
443 u64 limit;
444 struct lmb_property *p;
445
446 if (!memory_limit)
447 return;
448
449 /* Truncate the lmb regions to satisfy the memory limit. */
450 limit = memory_limit;
451 for (i = 0; i < lmb.memory.cnt; i++) {
452 if (limit > lmb.memory.region[i].size) {
453 limit -= lmb.memory.region[i].size;
454 continue;
455 }
456
457 lmb.memory.region[i].size = limit;
458 lmb.memory.cnt = i + 1;
459 break;
460 }
461
462 if (lmb.memory.region[0].size < lmb.rmo_size)
463 lmb.rmo_size = lmb.memory.region[0].size;
464
465 memory_limit = lmb_end_of_DRAM();
466
467 /* And truncate any reserves above the limit also. */
468 for (i = 0; i < lmb.reserved.cnt; i++) {
469 p = &lmb.reserved.region[i];
470
471 if (p->base > memory_limit)
472 p->size = 0;
473 else if ((p->base + p->size) > memory_limit)
474 p->size = memory_limit - p->base;
475
476 if (p->size == 0) {
477 lmb_remove_region(&lmb.reserved, i);
478 i--;
479 }
480 }
481 }
482
483 int __init lmb_is_reserved(u64 addr)
484 {
485 int i;
486
487 for (i = 0; i < lmb.reserved.cnt; i++) {
488 u64 upper = lmb.reserved.region[i].base +
489 lmb.reserved.region[i].size - 1;
490 if ((addr >= lmb.reserved.region[i].base) && (addr <= upper))
491 return 1;
492 }
493 return 0;
494 }
495
496 /*
497 * Given a <base, len>, find which memory regions belong to this range.
498 * Adjust the request and return a contiguous chunk.
499 */
500 int lmb_find(struct lmb_property *res)
501 {
502 int i;
503 u64 rstart, rend;
504
505 rstart = res->base;
506 rend = rstart + res->size - 1;
507
508 for (i = 0; i < lmb.memory.cnt; i++) {
509 u64 start = lmb.memory.region[i].base;
510 u64 end = start + lmb.memory.region[i].size - 1;
511
512 if (start > rend)
513 return -1;
514
515 if ((end >= rstart) && (start < rend)) {
516 /* adjust the request */
517 if (rstart < start)
518 rstart = start;
519 if (rend > end)
520 rend = end;
521 res->base = rstart;
522 res->size = rend - rstart + 1;
523 return 0;
524 }
525 }
526 return -1;
527 }
528
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