[LMB]: Make lmb support large physical addressing
[linux-2.6-block.git] / lib / lmb.c
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1/*
2 * Procedures for maintaining information about logical memory blocks.
3 *
4 * Peter Bergner, IBM Corp. June 2001.
5 * Copyright (C) 2001 Peter Bergner.
d9b2b2a2 6 *
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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
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13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/bitops.h>
d9b2b2a2 16#include <linux/lmb.h>
7c8c6b97 17
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18#undef DEBUG
19
eb481899 20#ifdef DEBUG
d9b2b2a2 21#define DBG(fmt...) LMB_DBG(fmt)
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22#else
23#define DBG(fmt...)
24#endif
25
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26#define LMB_ALLOC_ANYWHERE 0
27
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28struct lmb lmb;
29
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30void lmb_dump_all(void)
31{
32#ifdef DEBUG
33 unsigned long i;
34
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35 DBG("lmb_dump_all:\n");
36 DBG(" memory.cnt = 0x%lx\n", lmb.memory.cnt);
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37 DBG(" memory.size = 0x%llx\n",
38 (unsigned long long)lmb.memory.size);
7c8c6b97 39 for (i=0; i < lmb.memory.cnt ;i++) {
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40 DBG(" memory.region[0x%x].base = 0x%llx\n",
41 i, (unsigned long long)lmb.memory.region[i].base);
42 DBG(" .size = 0x%llx\n",
43 (unsigned long long)lmb.memory.region[i].size);
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44 }
45
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46 DBG("\n reserved.cnt = 0x%lx\n", lmb.reserved.cnt);
47 DBG(" reserved.size = 0x%lx\n", lmb.reserved.size);
7c8c6b97 48 for (i=0; i < lmb.reserved.cnt ;i++) {
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49 DBG(" reserved.region[0x%x].base = 0x%llx\n",
50 i, (unsigned long long)lmb.reserved.region[i].base);
51 DBG(" .size = 0x%llx\n",
52 (unsigned long long)lmb.reserved.region[i].size);
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53 }
54#endif /* DEBUG */
55}
56
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57static unsigned long __init lmb_addrs_overlap(u64 base1,
58 u64 size1, u64 base2, u64 size2)
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59{
60 return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
61}
62
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63static long __init lmb_addrs_adjacent(u64 base1, u64 size1,
64 u64 base2, u64 size2)
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65{
66 if (base2 == base1 + size1)
67 return 1;
68 else if (base1 == base2 + size2)
69 return -1;
70
71 return 0;
72}
73
74static long __init lmb_regions_adjacent(struct lmb_region *rgn,
75 unsigned long r1, unsigned long r2)
76{
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77 u64 base1 = rgn->region[r1].base;
78 u64 size1 = rgn->region[r1].size;
79 u64 base2 = rgn->region[r2].base;
80 u64 size2 = rgn->region[r2].size;
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81
82 return lmb_addrs_adjacent(base1, size1, base2, size2);
83}
84
2babf5c2 85static void __init lmb_remove_region(struct lmb_region *rgn, unsigned long r)
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86{
87 unsigned long i;
88
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89 for (i = r; i < rgn->cnt - 1; i++) {
90 rgn->region[i].base = rgn->region[i + 1].base;
91 rgn->region[i].size = rgn->region[i + 1].size;
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92 }
93 rgn->cnt--;
94}
95
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96/* Assumption: base addr of region 1 < base addr of region 2 */
97static void __init lmb_coalesce_regions(struct lmb_region *rgn,
98 unsigned long r1, unsigned long r2)
99{
100 rgn->region[r1].size += rgn->region[r2].size;
101 lmb_remove_region(rgn, r2);
102}
103
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104/* This routine called with relocation disabled. */
105void __init lmb_init(void)
106{
107 /* Create a dummy zero size LMB which will get coalesced away later.
108 * This simplifies the lmb_add() code below...
109 */
110 lmb.memory.region[0].base = 0;
111 lmb.memory.region[0].size = 0;
112 lmb.memory.cnt = 1;
113
114 /* Ditto. */
115 lmb.reserved.region[0].base = 0;
116 lmb.reserved.region[0].size = 0;
117 lmb.reserved.cnt = 1;
118}
119
120/* This routine may be called with relocation disabled. */
121void __init lmb_analyze(void)
122{
123 int i;
124
125 lmb.memory.size = 0;
126
127 for (i = 0; i < lmb.memory.cnt; i++)
128 lmb.memory.size += lmb.memory.region[i].size;
129}
130
131/* This routine called with relocation disabled. */
e5f27095 132static long __init lmb_add_region(struct lmb_region *rgn, u64 base, u64 size)
7c8c6b97 133{
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134 unsigned long coalesced = 0;
135 long adjacent, i;
7c8c6b97 136
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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
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143 /* First try and coalesce this LMB with another. */
144 for (i=0; i < rgn->cnt; i++) {
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145 u64 rgnbase = rgn->region[i].base;
146 u64 rgnsize = rgn->region[i].size;
7c8c6b97 147
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148 if ((rgnbase == base) && (rgnsize == size))
149 /* Already have this region, so we're done */
150 return 0;
151
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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 }
159 else if ( adjacent < 0 ) {
160 rgn->region[i].size += size;
161 coalesced++;
162 break;
163 }
164 }
165
166 if ((i < rgn->cnt-1) && lmb_regions_adjacent(rgn, i, i+1) ) {
167 lmb_coalesce_regions(rgn, i, i+1);
168 coalesced++;
169 }
170
171 if (coalesced)
172 return coalesced;
173 if (rgn->cnt >= MAX_LMB_REGIONS)
174 return -1;
175
176 /* Couldn't coalesce the LMB, so add it to the sorted table. */
177 for (i = rgn->cnt-1; i >= 0; i--) {
178 if (base < rgn->region[i].base) {
179 rgn->region[i+1].base = rgn->region[i].base;
180 rgn->region[i+1].size = rgn->region[i].size;
181 } else {
182 rgn->region[i+1].base = base;
183 rgn->region[i+1].size = size;
184 break;
185 }
186 }
187 rgn->cnt++;
188
189 return 0;
190}
191
192/* This routine may be called with relocation disabled. */
e5f27095 193long __init lmb_add(u64 base, u64 size)
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194{
195 struct lmb_region *_rgn = &(lmb.memory);
196
197 /* On pSeries LPAR systems, the first LMB is our RMO region. */
198 if (base == 0)
199 lmb.rmo_size = size;
200
201 return lmb_add_region(_rgn, base, size);
202
203}
204
e5f27095 205long __init lmb_reserve(u64 base, u64 size)
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206{
207 struct lmb_region *_rgn = &(lmb.reserved);
208
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209 BUG_ON(0 == size);
210
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211 return lmb_add_region(_rgn, base, size);
212}
213
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214long __init lmb_overlaps_region(struct lmb_region *rgn, u64 base,
215 u64 size)
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216{
217 unsigned long i;
218
219 for (i=0; i < rgn->cnt; i++) {
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220 u64 rgnbase = rgn->region[i].base;
221 u64 rgnsize = rgn->region[i].size;
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222 if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
223 break;
224 }
225 }
226
227 return (i < rgn->cnt) ? i : -1;
228}
229
e5f27095 230u64 __init lmb_alloc(u64 size, u64 align)
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231{
232 return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
233}
234
e5f27095 235u64 __init lmb_alloc_base(u64 size, u64 align, u64 max_addr)
d7a5b2ff 236{
e5f27095 237 u64 alloc;
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238
239 alloc = __lmb_alloc_base(size, align, max_addr);
240
2c276603 241 if (alloc == 0)
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242 panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
243 (unsigned long long) size, (unsigned long long) max_addr);
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244
245 return alloc;
246}
247
e5f27095 248static u64 lmb_align_down(u64 addr, u64 size)
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249{
250 return addr & ~(size - 1);
251}
252
e5f27095 253static u64 lmb_align_up(u64 addr, u64 size)
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254{
255 return (addr + (size - 1)) & ~(size - 1);
256}
257
e5f27095 258u64 __init __lmb_alloc_base(u64 size, u64 align, u64 max_addr)
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259{
260 long i, j;
e5f27095 261 u64 base = 0;
7c8c6b97 262
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263 BUG_ON(0 == size);
264
d9b2b2a2 265 /* On some platforms, make sure we allocate lowmem */
7c8c6b97 266 if (max_addr == LMB_ALLOC_ANYWHERE)
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267 max_addr = LMB_REAL_LIMIT;
268
7c8c6b97 269 for (i = lmb.memory.cnt-1; i >= 0; i--) {
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270 u64 lmbbase = lmb.memory.region[i].base;
271 u64 lmbsize = lmb.memory.region[i].size;
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272
273 if (max_addr == LMB_ALLOC_ANYWHERE)
d9b2b2a2 274 base = lmb_align_down(lmbbase + lmbsize - size, align);
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275 else if (lmbbase < max_addr) {
276 base = min(lmbbase + lmbsize, max_addr);
d9b2b2a2 277 base = lmb_align_down(base - size, align);
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278 } else
279 continue;
280
281 while ((lmbbase <= base) &&
282 ((j = lmb_overlaps_region(&lmb.reserved, base, size)) >= 0) )
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283 base = lmb_align_down(lmb.reserved.region[j].base - size,
284 align);
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285
286 if ((base != 0) && (lmbbase <= base))
287 break;
288 }
289
290 if (i < 0)
291 return 0;
292
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293 if (lmb_add_region(&lmb.reserved, base, lmb_align_up(size, align)) < 0)
294 return 0;
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295
296 return base;
297}
298
299/* You must call lmb_analyze() before this. */
e5f27095 300u64 __init lmb_phys_mem_size(void)
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301{
302 return lmb.memory.size;
303}
304
e5f27095 305u64 __init lmb_end_of_DRAM(void)
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306{
307 int idx = lmb.memory.cnt - 1;
308
309 return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
310}
311
2babf5c2 312/* You must call lmb_analyze() after this. */
e5f27095 313void __init lmb_enforce_memory_limit(u64 memory_limit)
7c8c6b97 314{
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315 unsigned long i;
316 u64 limit;
2babf5c2 317 struct lmb_property *p;
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318
319 if (! memory_limit)
320 return;
321
2babf5c2 322 /* Truncate the lmb regions to satisfy the memory limit. */
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323 limit = memory_limit;
324 for (i = 0; i < lmb.memory.cnt; i++) {
325 if (limit > lmb.memory.region[i].size) {
326 limit -= lmb.memory.region[i].size;
327 continue;
328 }
329
330 lmb.memory.region[i].size = limit;
331 lmb.memory.cnt = i + 1;
332 break;
333 }
2babf5c2 334
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335 if (lmb.memory.region[0].size < lmb.rmo_size)
336 lmb.rmo_size = lmb.memory.region[0].size;
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337
338 /* And truncate any reserves above the limit also. */
339 for (i = 0; i < lmb.reserved.cnt; i++) {
340 p = &lmb.reserved.region[i];
341
342 if (p->base > memory_limit)
343 p->size = 0;
344 else if ((p->base + p->size) > memory_limit)
345 p->size = memory_limit - p->base;
346
347 if (p->size == 0) {
348 lmb_remove_region(&lmb.reserved, i);
349 i--;
350 }
351 }
7c8c6b97 352}
f98eeb4e 353
e5f27095 354int __init lmb_is_reserved(u64 addr)
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355{
356 int i;
357
358 for (i = 0; i < lmb.reserved.cnt; i++) {
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359 u64 upper = lmb.reserved.region[i].base +
360 lmb.reserved.region[i].size - 1;
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361 if ((addr >= lmb.reserved.region[i].base) && (addr <= upper))
362 return 1;
363 }
364 return 0;
365}