xref: /openbmc/u-boot/lib/lmb.c (revision ae485b54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Procedures for maintaining information about logical memory blocks.
4  *
5  * Peter Bergner, IBM Corp.	June 2001.
6  * Copyright (C) 2001 Peter Bergner.
7  */
8 
9 #include <common.h>
10 #include <lmb.h>
11 
12 #define LMB_ALLOC_ANYWHERE	0
13 
14 void lmb_dump_all(struct lmb *lmb)
15 {
16 #ifdef DEBUG
17 	unsigned long i;
18 
19 	debug("lmb_dump_all:\n");
20 	debug("    memory.cnt		   = 0x%lx\n", lmb->memory.cnt);
21 	debug("    memory.size		   = 0x%llx\n",
22 	      (unsigned long long)lmb->memory.size);
23 	for (i=0; i < lmb->memory.cnt ;i++) {
24 		debug("    memory.reg[0x%lx].base   = 0x%llx\n", i,
25 			(long long unsigned)lmb->memory.region[i].base);
26 		debug("		   .size   = 0x%llx\n",
27 			(long long unsigned)lmb->memory.region[i].size);
28 	}
29 
30 	debug("\n    reserved.cnt	   = 0x%lx\n",
31 		lmb->reserved.cnt);
32 	debug("    reserved.size	   = 0x%llx\n",
33 		(long long unsigned)lmb->reserved.size);
34 	for (i=0; i < lmb->reserved.cnt ;i++) {
35 		debug("    reserved.reg[0x%lx].base = 0x%llx\n", i,
36 			(long long unsigned)lmb->reserved.region[i].base);
37 		debug("		     .size = 0x%llx\n",
38 			(long long unsigned)lmb->reserved.region[i].size);
39 	}
40 #endif /* DEBUG */
41 }
42 
43 static long lmb_addrs_overlap(phys_addr_t base1,
44 		phys_size_t size1, phys_addr_t base2, phys_size_t size2)
45 {
46 	return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
47 }
48 
49 static long lmb_addrs_adjacent(phys_addr_t base1, phys_size_t size1,
50 		phys_addr_t base2, phys_size_t size2)
51 {
52 	if (base2 == base1 + size1)
53 		return 1;
54 	else if (base1 == base2 + size2)
55 		return -1;
56 
57 	return 0;
58 }
59 
60 static long lmb_regions_adjacent(struct lmb_region *rgn,
61 		unsigned long r1, unsigned long r2)
62 {
63 	phys_addr_t base1 = rgn->region[r1].base;
64 	phys_size_t size1 = rgn->region[r1].size;
65 	phys_addr_t base2 = rgn->region[r2].base;
66 	phys_size_t size2 = rgn->region[r2].size;
67 
68 	return lmb_addrs_adjacent(base1, size1, base2, size2);
69 }
70 
71 static void lmb_remove_region(struct lmb_region *rgn, unsigned long r)
72 {
73 	unsigned long i;
74 
75 	for (i = r; i < rgn->cnt - 1; i++) {
76 		rgn->region[i].base = rgn->region[i + 1].base;
77 		rgn->region[i].size = rgn->region[i + 1].size;
78 	}
79 	rgn->cnt--;
80 }
81 
82 /* Assumption: base addr of region 1 < base addr of region 2 */
83 static void lmb_coalesce_regions(struct lmb_region *rgn,
84 		unsigned long r1, unsigned long r2)
85 {
86 	rgn->region[r1].size += rgn->region[r2].size;
87 	lmb_remove_region(rgn, r2);
88 }
89 
90 void lmb_init(struct lmb *lmb)
91 {
92 	/* Create a dummy zero size LMB which will get coalesced away later.
93 	 * This simplifies the lmb_add() code below...
94 	 */
95 	lmb->memory.region[0].base = 0;
96 	lmb->memory.region[0].size = 0;
97 	lmb->memory.cnt = 1;
98 	lmb->memory.size = 0;
99 
100 	/* Ditto. */
101 	lmb->reserved.region[0].base = 0;
102 	lmb->reserved.region[0].size = 0;
103 	lmb->reserved.cnt = 1;
104 	lmb->reserved.size = 0;
105 }
106 
107 /* This routine called with relocation disabled. */
108 static long lmb_add_region(struct lmb_region *rgn, phys_addr_t base, phys_size_t size)
109 {
110 	unsigned long coalesced = 0;
111 	long adjacent, i;
112 
113 	if ((rgn->cnt == 1) && (rgn->region[0].size == 0)) {
114 		rgn->region[0].base = base;
115 		rgn->region[0].size = size;
116 		return 0;
117 	}
118 
119 	/* First try and coalesce this LMB with another. */
120 	for (i=0; i < rgn->cnt; i++) {
121 		phys_addr_t rgnbase = rgn->region[i].base;
122 		phys_size_t rgnsize = rgn->region[i].size;
123 
124 		if ((rgnbase == base) && (rgnsize == size))
125 			/* Already have this region, so we're done */
126 			return 0;
127 
128 		adjacent = lmb_addrs_adjacent(base,size,rgnbase,rgnsize);
129 		if ( adjacent > 0 ) {
130 			rgn->region[i].base -= size;
131 			rgn->region[i].size += size;
132 			coalesced++;
133 			break;
134 		}
135 		else if ( adjacent < 0 ) {
136 			rgn->region[i].size += size;
137 			coalesced++;
138 			break;
139 		}
140 	}
141 
142 	if ((i < rgn->cnt-1) && lmb_regions_adjacent(rgn, i, i+1) ) {
143 		lmb_coalesce_regions(rgn, i, i+1);
144 		coalesced++;
145 	}
146 
147 	if (coalesced)
148 		return coalesced;
149 	if (rgn->cnt >= MAX_LMB_REGIONS)
150 		return -1;
151 
152 	/* Couldn't coalesce the LMB, so add it to the sorted table. */
153 	for (i = rgn->cnt-1; i >= 0; i--) {
154 		if (base < rgn->region[i].base) {
155 			rgn->region[i+1].base = rgn->region[i].base;
156 			rgn->region[i+1].size = rgn->region[i].size;
157 		} else {
158 			rgn->region[i+1].base = base;
159 			rgn->region[i+1].size = size;
160 			break;
161 		}
162 	}
163 
164 	if (base < rgn->region[0].base) {
165 		rgn->region[0].base = base;
166 		rgn->region[0].size = size;
167 	}
168 
169 	rgn->cnt++;
170 
171 	return 0;
172 }
173 
174 /* This routine may be called with relocation disabled. */
175 long lmb_add(struct lmb *lmb, phys_addr_t base, phys_size_t size)
176 {
177 	struct lmb_region *_rgn = &(lmb->memory);
178 
179 	return lmb_add_region(_rgn, base, size);
180 }
181 
182 long lmb_free(struct lmb *lmb, phys_addr_t base, phys_size_t size)
183 {
184 	struct lmb_region *rgn = &(lmb->reserved);
185 	phys_addr_t rgnbegin, rgnend;
186 	phys_addr_t end = base + size;
187 	int i;
188 
189 	rgnbegin = rgnend = 0; /* supress gcc warnings */
190 
191 	/* Find the region where (base, size) belongs to */
192 	for (i=0; i < rgn->cnt; i++) {
193 		rgnbegin = rgn->region[i].base;
194 		rgnend = rgnbegin + rgn->region[i].size;
195 
196 		if ((rgnbegin <= base) && (end <= rgnend))
197 			break;
198 	}
199 
200 	/* Didn't find the region */
201 	if (i == rgn->cnt)
202 		return -1;
203 
204 	/* Check to see if we are removing entire region */
205 	if ((rgnbegin == base) && (rgnend == end)) {
206 		lmb_remove_region(rgn, i);
207 		return 0;
208 	}
209 
210 	/* Check to see if region is matching at the front */
211 	if (rgnbegin == base) {
212 		rgn->region[i].base = end;
213 		rgn->region[i].size -= size;
214 		return 0;
215 	}
216 
217 	/* Check to see if the region is matching at the end */
218 	if (rgnend == end) {
219 		rgn->region[i].size -= size;
220 		return 0;
221 	}
222 
223 	/*
224 	 * We need to split the entry -  adjust the current one to the
225 	 * beginging of the hole and add the region after hole.
226 	 */
227 	rgn->region[i].size = base - rgn->region[i].base;
228 	return lmb_add_region(rgn, end, rgnend - end);
229 }
230 
231 long lmb_reserve(struct lmb *lmb, phys_addr_t base, phys_size_t size)
232 {
233 	struct lmb_region *_rgn = &(lmb->reserved);
234 
235 	return lmb_add_region(_rgn, base, size);
236 }
237 
238 static long lmb_overlaps_region(struct lmb_region *rgn, phys_addr_t base,
239 				phys_size_t size)
240 {
241 	unsigned long i;
242 
243 	for (i=0; i < rgn->cnt; i++) {
244 		phys_addr_t rgnbase = rgn->region[i].base;
245 		phys_size_t rgnsize = rgn->region[i].size;
246 		if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
247 			break;
248 		}
249 	}
250 
251 	return (i < rgn->cnt) ? i : -1;
252 }
253 
254 phys_addr_t lmb_alloc(struct lmb *lmb, phys_size_t size, ulong align)
255 {
256 	return lmb_alloc_base(lmb, size, align, LMB_ALLOC_ANYWHERE);
257 }
258 
259 phys_addr_t lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align, phys_addr_t max_addr)
260 {
261 	phys_addr_t alloc;
262 
263 	alloc = __lmb_alloc_base(lmb, size, align, max_addr);
264 
265 	if (alloc == 0)
266 		printf("ERROR: Failed to allocate 0x%lx bytes below 0x%lx.\n",
267 		      (ulong)size, (ulong)max_addr);
268 
269 	return alloc;
270 }
271 
272 static phys_addr_t lmb_align_down(phys_addr_t addr, phys_size_t size)
273 {
274 	return addr & ~(size - 1);
275 }
276 
277 static phys_addr_t lmb_align_up(phys_addr_t addr, ulong size)
278 {
279 	return (addr + (size - 1)) & ~(size - 1);
280 }
281 
282 phys_addr_t __lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align, phys_addr_t max_addr)
283 {
284 	long i, j;
285 	phys_addr_t base = 0;
286 	phys_addr_t res_base;
287 
288 	for (i = lmb->memory.cnt-1; i >= 0; i--) {
289 		phys_addr_t lmbbase = lmb->memory.region[i].base;
290 		phys_size_t lmbsize = lmb->memory.region[i].size;
291 
292 		if (lmbsize < size)
293 			continue;
294 		if (max_addr == LMB_ALLOC_ANYWHERE)
295 			base = lmb_align_down(lmbbase + lmbsize - size, align);
296 		else if (lmbbase < max_addr) {
297 			base = lmbbase + lmbsize;
298 			if (base < lmbbase)
299 				base = -1;
300 			base = min(base, max_addr);
301 			base = lmb_align_down(base - size, align);
302 		} else
303 			continue;
304 
305 		while (base && lmbbase <= base) {
306 			j = lmb_overlaps_region(&lmb->reserved, base, size);
307 			if (j < 0) {
308 				/* This area isn't reserved, take it */
309 				if (lmb_add_region(&lmb->reserved, base,
310 							lmb_align_up(size,
311 								align)) < 0)
312 					return 0;
313 				return base;
314 			}
315 			res_base = lmb->reserved.region[j].base;
316 			if (res_base < size)
317 				break;
318 			base = lmb_align_down(res_base - size, align);
319 		}
320 	}
321 	return 0;
322 }
323 
324 int lmb_is_reserved(struct lmb *lmb, phys_addr_t addr)
325 {
326 	int i;
327 
328 	for (i = 0; i < lmb->reserved.cnt; i++) {
329 		phys_addr_t upper = lmb->reserved.region[i].base +
330 			lmb->reserved.region[i].size - 1;
331 		if ((addr >= lmb->reserved.region[i].base) && (addr <= upper))
332 			return 1;
333 	}
334 	return 0;
335 }
336 
337 __weak void board_lmb_reserve(struct lmb *lmb)
338 {
339 	/* please define platform specific board_lmb_reserve() */
340 }
341 
342 __weak void arch_lmb_reserve(struct lmb *lmb)
343 {
344 	/* please define platform specific arch_lmb_reserve() */
345 }
346