2 * Procedures for maintaining information about logical memory blocks.
4 * Peter Bergner, IBM Corp. June 2001.
5 * Copyright (C) 2001 Peter Bergner.
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.
13 #include <linux/config.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/bitops.h>
17 #include <asm/types.h>
22 #include "mmu_decl.h" /* for __max_low_memory */
29 #define DBG(fmt...) udbg_printf(fmt)
34 #define LMB_ALLOC_ANYWHERE 0
38 void lmb_dump_all(void)
43 DBG("lmb_dump_all:\n");
44 DBG(" memory.cnt = 0x%lx\n", lmb.memory.cnt);
45 DBG(" memory.size = 0x%lx\n", lmb.memory.size);
46 for (i=0; i < lmb.memory.cnt ;i++) {
47 DBG(" memory.region[0x%x].base = 0x%lx\n",
48 i, lmb.memory.region[i].base);
49 DBG(" .size = 0x%lx\n",
50 lmb.memory.region[i].size);
53 DBG("\n reserved.cnt = 0x%lx\n", lmb.reserved.cnt);
54 DBG(" reserved.size = 0x%lx\n", lmb.reserved.size);
55 for (i=0; i < lmb.reserved.cnt ;i++) {
56 DBG(" reserved.region[0x%x].base = 0x%lx\n",
57 i, lmb.reserved.region[i].base);
58 DBG(" .size = 0x%lx\n",
59 lmb.reserved.region[i].size);
64 static unsigned long __init lmb_addrs_overlap(unsigned long base1,
65 unsigned long size1, unsigned long base2, unsigned long size2)
67 return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
70 static long __init lmb_addrs_adjacent(unsigned long base1, unsigned long size1,
71 unsigned long base2, unsigned long size2)
73 if (base2 == base1 + size1)
75 else if (base1 == base2 + size2)
81 static long __init lmb_regions_adjacent(struct lmb_region *rgn,
82 unsigned long r1, unsigned long r2)
84 unsigned long base1 = rgn->region[r1].base;
85 unsigned long size1 = rgn->region[r1].size;
86 unsigned long base2 = rgn->region[r2].base;
87 unsigned long size2 = rgn->region[r2].size;
89 return lmb_addrs_adjacent(base1, size1, base2, size2);
92 /* Assumption: base addr of region 1 < base addr of region 2 */
93 static void __init lmb_coalesce_regions(struct lmb_region *rgn,
94 unsigned long r1, unsigned long r2)
98 rgn->region[r1].size += rgn->region[r2].size;
99 for (i=r2; i < rgn->cnt-1; i++) {
100 rgn->region[i].base = rgn->region[i+1].base;
101 rgn->region[i].size = rgn->region[i+1].size;
106 /* This routine called with relocation disabled. */
107 void __init lmb_init(void)
109 /* Create a dummy zero size LMB which will get coalesced away later.
110 * This simplifies the lmb_add() code below...
112 lmb.memory.region[0].base = 0;
113 lmb.memory.region[0].size = 0;
117 lmb.reserved.region[0].base = 0;
118 lmb.reserved.region[0].size = 0;
119 lmb.reserved.cnt = 1;
122 /* This routine may be called with relocation disabled. */
123 void __init lmb_analyze(void)
129 for (i = 0; i < lmb.memory.cnt; i++)
130 lmb.memory.size += lmb.memory.region[i].size;
133 /* This routine called with relocation disabled. */
134 static long __init lmb_add_region(struct lmb_region *rgn, unsigned long base,
137 unsigned long i, coalesced = 0;
140 /* First try and coalesce this LMB with another. */
141 for (i=0; i < rgn->cnt; i++) {
142 unsigned long rgnbase = rgn->region[i].base;
143 unsigned long rgnsize = rgn->region[i].size;
145 adjacent = lmb_addrs_adjacent(base,size,rgnbase,rgnsize);
146 if ( adjacent > 0 ) {
147 rgn->region[i].base -= size;
148 rgn->region[i].size += size;
152 else if ( adjacent < 0 ) {
153 rgn->region[i].size += size;
159 if ((i < rgn->cnt-1) && lmb_regions_adjacent(rgn, i, i+1) ) {
160 lmb_coalesce_regions(rgn, i, i+1);
166 if (rgn->cnt >= MAX_LMB_REGIONS)
169 /* Couldn't coalesce the LMB, so add it to the sorted table. */
170 for (i = rgn->cnt-1; i >= 0; i--) {
171 if (base < rgn->region[i].base) {
172 rgn->region[i+1].base = rgn->region[i].base;
173 rgn->region[i+1].size = rgn->region[i].size;
175 rgn->region[i+1].base = base;
176 rgn->region[i+1].size = size;
185 /* This routine may be called with relocation disabled. */
186 long __init lmb_add(unsigned long base, unsigned long size)
188 struct lmb_region *_rgn = &(lmb.memory);
190 /* On pSeries LPAR systems, the first LMB is our RMO region. */
194 return lmb_add_region(_rgn, base, size);
198 long __init lmb_reserve(unsigned long base, unsigned long size)
200 struct lmb_region *_rgn = &(lmb.reserved);
204 return lmb_add_region(_rgn, base, size);
207 long __init lmb_overlaps_region(struct lmb_region *rgn, unsigned long base,
212 for (i=0; i < rgn->cnt; i++) {
213 unsigned long rgnbase = rgn->region[i].base;
214 unsigned long rgnsize = rgn->region[i].size;
215 if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
220 return (i < rgn->cnt) ? i : -1;
223 unsigned long __init lmb_alloc(unsigned long size, unsigned long align)
225 return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
228 unsigned long __init lmb_alloc_base(unsigned long size, unsigned long align,
229 unsigned long max_addr)
233 alloc = __lmb_alloc_base(size, align, max_addr);
236 panic("ERROR: Failed to allocate 0x%lx bytes below 0x%lx.\n",
242 unsigned long __init __lmb_alloc_base(unsigned long size, unsigned long align,
243 unsigned long max_addr)
246 unsigned long base = 0;
251 /* On 32-bit, make sure we allocate lowmem */
252 if (max_addr == LMB_ALLOC_ANYWHERE)
253 max_addr = __max_low_memory;
255 for (i = lmb.memory.cnt-1; i >= 0; i--) {
256 unsigned long lmbbase = lmb.memory.region[i].base;
257 unsigned long lmbsize = lmb.memory.region[i].size;
259 if (max_addr == LMB_ALLOC_ANYWHERE)
260 base = _ALIGN_DOWN(lmbbase + lmbsize - size, align);
261 else if (lmbbase < max_addr) {
262 base = min(lmbbase + lmbsize, max_addr);
263 base = _ALIGN_DOWN(base - size, align);
267 while ((lmbbase <= base) &&
268 ((j = lmb_overlaps_region(&lmb.reserved, base, size)) >= 0) )
269 base = _ALIGN_DOWN(lmb.reserved.region[j].base - size,
272 if ((base != 0) && (lmbbase <= base))
279 lmb_add_region(&lmb.reserved, base, size);
284 /* You must call lmb_analyze() before this. */
285 unsigned long __init lmb_phys_mem_size(void)
287 return lmb.memory.size;
290 unsigned long __init lmb_end_of_DRAM(void)
292 int idx = lmb.memory.cnt - 1;
294 return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
298 * Truncate the lmb list to memory_limit if it's set
299 * You must call lmb_analyze() after this.
301 void __init lmb_enforce_memory_limit(unsigned long memory_limit)
303 unsigned long i, limit;
308 limit = memory_limit;
309 for (i = 0; i < lmb.memory.cnt; i++) {
310 if (limit > lmb.memory.region[i].size) {
311 limit -= lmb.memory.region[i].size;
315 lmb.memory.region[i].size = limit;
316 lmb.memory.cnt = i + 1;