xref: /openbmc/u-boot/lib/lmb.c (revision b6152676)
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  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <lmb.h>
12 
13 #define LMB_ALLOC_ANYWHERE	0
14 
15 void lmb_dump_all(struct lmb *lmb)
16 {
17 #ifdef DEBUG
18 	unsigned long i;
19 
20 	debug("lmb_dump_all:\n");
21 	debug("    memory.cnt		   = 0x%lx\n", lmb->memory.cnt);
22 	debug("    memory.size		   = 0x%llx\n",
23 	      (unsigned long long)lmb->memory.size);
24 	for (i=0; i < lmb->memory.cnt ;i++) {
25 		debug("    memory.reg[0x%lx].base   = 0x%llx\n", i,
26 			(long long unsigned)lmb->memory.region[i].base);
27 		debug("		   .size   = 0x%llx\n",
28 			(long long unsigned)lmb->memory.region[i].size);
29 	}
30 
31 	debug("\n    reserved.cnt	   = 0x%lx\n",
32 		lmb->reserved.cnt);
33 	debug("    reserved.size	   = 0x%llx\n",
34 		(long long unsigned)lmb->reserved.size);
35 	for (i=0; i < lmb->reserved.cnt ;i++) {
36 		debug("    reserved.reg[0x%lx].base = 0x%llx\n", i,
37 			(long long unsigned)lmb->reserved.region[i].base);
38 		debug("		     .size = 0x%llx\n",
39 			(long long unsigned)lmb->reserved.region[i].size);
40 	}
41 #endif /* DEBUG */
42 }
43 
44 static long lmb_addrs_overlap(phys_addr_t base1,
45 		phys_size_t size1, phys_addr_t base2, phys_size_t size2)
46 {
47 	return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
48 }
49 
50 static long lmb_addrs_adjacent(phys_addr_t base1, phys_size_t size1,
51 		phys_addr_t base2, phys_size_t size2)
52 {
53 	if (base2 == base1 + size1)
54 		return 1;
55 	else if (base1 == base2 + size2)
56 		return -1;
57 
58 	return 0;
59 }
60 
61 static long lmb_regions_adjacent(struct lmb_region *rgn,
62 		unsigned long r1, unsigned long r2)
63 {
64 	phys_addr_t base1 = rgn->region[r1].base;
65 	phys_size_t size1 = rgn->region[r1].size;
66 	phys_addr_t base2 = rgn->region[r2].base;
67 	phys_size_t size2 = rgn->region[r2].size;
68 
69 	return lmb_addrs_adjacent(base1, size1, base2, size2);
70 }
71 
72 static void lmb_remove_region(struct lmb_region *rgn, unsigned long r)
73 {
74 	unsigned long i;
75 
76 	for (i = r; i < rgn->cnt - 1; i++) {
77 		rgn->region[i].base = rgn->region[i + 1].base;
78 		rgn->region[i].size = rgn->region[i + 1].size;
79 	}
80 	rgn->cnt--;
81 }
82 
83 /* Assumption: base addr of region 1 < base addr of region 2 */
84 static void lmb_coalesce_regions(struct lmb_region *rgn,
85 		unsigned long r1, unsigned long r2)
86 {
87 	rgn->region[r1].size += rgn->region[r2].size;
88 	lmb_remove_region(rgn, r2);
89 }
90 
91 void lmb_init(struct lmb *lmb)
92 {
93 	/* Create a dummy zero size LMB which will get coalesced away later.
94 	 * This simplifies the lmb_add() code below...
95 	 */
96 	lmb->memory.region[0].base = 0;
97 	lmb->memory.region[0].size = 0;
98 	lmb->memory.cnt = 1;
99 	lmb->memory.size = 0;
100 
101 	/* Ditto. */
102 	lmb->reserved.region[0].base = 0;
103 	lmb->reserved.region[0].size = 0;
104 	lmb->reserved.cnt = 1;
105 	lmb->reserved.size = 0;
106 }
107 
108 /* This routine called with relocation disabled. */
109 static long lmb_add_region(struct lmb_region *rgn, phys_addr_t base, phys_size_t size)
110 {
111 	unsigned long coalesced = 0;
112 	long adjacent, i;
113 
114 	if ((rgn->cnt == 1) && (rgn->region[0].size == 0)) {
115 		rgn->region[0].base = base;
116 		rgn->region[0].size = size;
117 		return 0;
118 	}
119 
120 	/* First try and coalesce this LMB with another. */
121 	for (i=0; i < rgn->cnt; i++) {
122 		phys_addr_t rgnbase = rgn->region[i].base;
123 		phys_size_t rgnsize = rgn->region[i].size;
124 
125 		if ((rgnbase == base) && (rgnsize == size))
126 			/* Already have this region, so we're done */
127 			return 0;
128 
129 		adjacent = lmb_addrs_adjacent(base,size,rgnbase,rgnsize);
130 		if ( adjacent > 0 ) {
131 			rgn->region[i].base -= size;
132 			rgn->region[i].size += size;
133 			coalesced++;
134 			break;
135 		}
136 		else if ( adjacent < 0 ) {
137 			rgn->region[i].size += size;
138 			coalesced++;
139 			break;
140 		}
141 	}
142 
143 	if ((i < rgn->cnt-1) && lmb_regions_adjacent(rgn, i, i+1) ) {
144 		lmb_coalesce_regions(rgn, i, i+1);
145 		coalesced++;
146 	}
147 
148 	if (coalesced)
149 		return coalesced;
150 	if (rgn->cnt >= MAX_LMB_REGIONS)
151 		return -1;
152 
153 	/* Couldn't coalesce the LMB, so add it to the sorted table. */
154 	for (i = rgn->cnt-1; i >= 0; i--) {
155 		if (base < rgn->region[i].base) {
156 			rgn->region[i+1].base = rgn->region[i].base;
157 			rgn->region[i+1].size = rgn->region[i].size;
158 		} else {
159 			rgn->region[i+1].base = base;
160 			rgn->region[i+1].size = size;
161 			break;
162 		}
163 	}
164 
165 	if (base < rgn->region[0].base) {
166 		rgn->region[0].base = base;
167 		rgn->region[0].size = size;
168 	}
169 
170 	rgn->cnt++;
171 
172 	return 0;
173 }
174 
175 /* This routine may be called with relocation disabled. */
176 long lmb_add(struct lmb *lmb, phys_addr_t base, phys_size_t size)
177 {
178 	struct lmb_region *_rgn = &(lmb->memory);
179 
180 	return lmb_add_region(_rgn, base, size);
181 }
182 
183 long lmb_free(struct lmb *lmb, phys_addr_t base, phys_size_t size)
184 {
185 	struct lmb_region *rgn = &(lmb->reserved);
186 	phys_addr_t rgnbegin, rgnend;
187 	phys_addr_t end = base + size;
188 	int i;
189 
190 	rgnbegin = rgnend = 0; /* supress gcc warnings */
191 
192 	/* Find the region where (base, size) belongs to */
193 	for (i=0; i < rgn->cnt; i++) {
194 		rgnbegin = rgn->region[i].base;
195 		rgnend = rgnbegin + rgn->region[i].size;
196 
197 		if ((rgnbegin <= base) && (end <= rgnend))
198 			break;
199 	}
200 
201 	/* Didn't find the region */
202 	if (i == rgn->cnt)
203 		return -1;
204 
205 	/* Check to see if we are removing entire region */
206 	if ((rgnbegin == base) && (rgnend == end)) {
207 		lmb_remove_region(rgn, i);
208 		return 0;
209 	}
210 
211 	/* Check to see if region is matching at the front */
212 	if (rgnbegin == base) {
213 		rgn->region[i].base = end;
214 		rgn->region[i].size -= size;
215 		return 0;
216 	}
217 
218 	/* Check to see if the region is matching at the end */
219 	if (rgnend == end) {
220 		rgn->region[i].size -= size;
221 		return 0;
222 	}
223 
224 	/*
225 	 * We need to split the entry -  adjust the current one to the
226 	 * beginging of the hole and add the region after hole.
227 	 */
228 	rgn->region[i].size = base - rgn->region[i].base;
229 	return lmb_add_region(rgn, end, rgnend - end);
230 }
231 
232 long lmb_reserve(struct lmb *lmb, phys_addr_t base, phys_size_t size)
233 {
234 	struct lmb_region *_rgn = &(lmb->reserved);
235 
236 	return lmb_add_region(_rgn, base, size);
237 }
238 
239 static long lmb_overlaps_region(struct lmb_region *rgn, phys_addr_t base,
240 				phys_size_t size)
241 {
242 	unsigned long i;
243 
244 	for (i=0; i < rgn->cnt; i++) {
245 		phys_addr_t rgnbase = rgn->region[i].base;
246 		phys_size_t rgnsize = rgn->region[i].size;
247 		if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
248 			break;
249 		}
250 	}
251 
252 	return (i < rgn->cnt) ? i : -1;
253 }
254 
255 phys_addr_t lmb_alloc(struct lmb *lmb, phys_size_t size, ulong align)
256 {
257 	return lmb_alloc_base(lmb, size, align, LMB_ALLOC_ANYWHERE);
258 }
259 
260 phys_addr_t lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align, phys_addr_t max_addr)
261 {
262 	phys_addr_t alloc;
263 
264 	alloc = __lmb_alloc_base(lmb, size, align, max_addr);
265 
266 	if (alloc == 0)
267 		printf("ERROR: Failed to allocate 0x%lx bytes below 0x%lx.\n",
268 		      (ulong)size, (ulong)max_addr);
269 
270 	return alloc;
271 }
272 
273 static phys_addr_t lmb_align_down(phys_addr_t addr, phys_size_t size)
274 {
275 	return addr & ~(size - 1);
276 }
277 
278 static phys_addr_t lmb_align_up(phys_addr_t addr, ulong size)
279 {
280 	return (addr + (size - 1)) & ~(size - 1);
281 }
282 
283 phys_addr_t __lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align, phys_addr_t max_addr)
284 {
285 	long i, j;
286 	phys_addr_t base = 0;
287 	phys_addr_t res_base;
288 
289 	for (i = lmb->memory.cnt-1; i >= 0; i--) {
290 		phys_addr_t lmbbase = lmb->memory.region[i].base;
291 		phys_size_t lmbsize = lmb->memory.region[i].size;
292 
293 		if (lmbsize < size)
294 			continue;
295 		if (max_addr == LMB_ALLOC_ANYWHERE)
296 			base = lmb_align_down(lmbbase + lmbsize - size, align);
297 		else if (lmbbase < max_addr) {
298 			base = lmbbase + lmbsize;
299 			if (base < lmbbase)
300 				base = -1;
301 			base = min(base, max_addr);
302 			base = lmb_align_down(base - size, align);
303 		} else
304 			continue;
305 
306 		while (base && lmbbase <= base) {
307 			j = lmb_overlaps_region(&lmb->reserved, base, size);
308 			if (j < 0) {
309 				/* This area isn't reserved, take it */
310 				if (lmb_add_region(&lmb->reserved, base,
311 							lmb_align_up(size,
312 								align)) < 0)
313 					return 0;
314 				return base;
315 			}
316 			res_base = lmb->reserved.region[j].base;
317 			if (res_base < size)
318 				break;
319 			base = lmb_align_down(res_base - size, align);
320 		}
321 	}
322 	return 0;
323 }
324 
325 int lmb_is_reserved(struct lmb *lmb, phys_addr_t addr)
326 {
327 	int i;
328 
329 	for (i = 0; i < lmb->reserved.cnt; i++) {
330 		phys_addr_t upper = lmb->reserved.region[i].base +
331 			lmb->reserved.region[i].size - 1;
332 		if ((addr >= lmb->reserved.region[i].base) && (addr <= upper))
333 			return 1;
334 	}
335 	return 0;
336 }
337 
338 __weak void board_lmb_reserve(struct lmb *lmb)
339 {
340 	/* please define platform specific board_lmb_reserve() */
341 }
342 
343 __weak void arch_lmb_reserve(struct lmb *lmb)
344 {
345 	/* please define platform specific arch_lmb_reserve() */
346 }
347