fdt_memory.c revision 1.6
1 /* $NetBSD: fdt_memory.c,v 1.6 2022/08/06 20:16:42 ryo Exp $ */ 2 3 /*- 4 * Copyright (c) 2018 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jared McNeill <jmcneill (at) invisible.ca>. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include "opt_fdt.h" 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: fdt_memory.c,v 1.6 2022/08/06 20:16:42 ryo Exp $"); 36 37 #include <sys/param.h> 38 #include <sys/queue.h> 39 40 #include <libfdt.h> 41 #include <dev/fdt/fdtvar.h> 42 #include <dev/fdt/fdt_memory.h> 43 44 #ifndef FDT_MEMORY_RANGES 45 #define FDT_MEMORY_RANGES 256 46 #endif 47 48 struct fdt_memory_range { 49 struct fdt_memory mr_mem; 50 bool mr_used; 51 TAILQ_ENTRY(fdt_memory_range) mr_list; 52 }; 53 54 static TAILQ_HEAD(fdt_memory_rangehead, fdt_memory_range) fdt_memory_ranges = 55 TAILQ_HEAD_INITIALIZER(fdt_memory_ranges); 56 57 static struct fdt_memory_range fdt_memory_range_pool[FDT_MEMORY_RANGES]; 58 59 static struct fdt_memory_range * 60 fdt_memory_range_alloc(void) 61 { 62 for (size_t n = 0; n < FDT_MEMORY_RANGES; n++) 63 if (!fdt_memory_range_pool[n].mr_used) { 64 fdt_memory_range_pool[n].mr_used = true; 65 return &fdt_memory_range_pool[n]; 66 } 67 68 printf("%s: no free memory ranges, increase FDT_MEMORY_RANGES!\n", __func__); 69 return NULL; 70 } 71 72 static void 73 fdt_memory_range_free(struct fdt_memory_range *mr) 74 { 75 mr->mr_used = false; 76 } 77 78 /* 79 * Get all of physical memory, including holes. 80 */ 81 void 82 fdt_memory_get(uint64_t *pstart, uint64_t *pend) 83 { 84 const int memory = OF_finddevice("/memory"); 85 uint64_t cur_addr, cur_size; 86 int index, nadd; 87 88 for (index = 0, nadd = 0; 89 fdtbus_get_reg64(memory, index, &cur_addr, &cur_size) == 0; 90 index++) { 91 if (cur_size == 0) 92 continue; 93 fdt_memory_add_range(cur_addr, cur_size); 94 95 if (nadd++ == 0) { 96 *pstart = cur_addr; 97 *pend = cur_addr + cur_size; 98 continue; 99 } 100 if (cur_addr < *pstart) 101 *pstart = cur_addr; 102 if (cur_addr + cur_size > *pend) 103 *pend = cur_addr + cur_size; 104 } 105 if (nadd == 0) 106 panic("Cannot determine memory size"); 107 } 108 109 /* 110 * Exclude memory ranges from memory config from the device tree 111 */ 112 void 113 fdt_memory_remove_reserved(uint64_t min_addr, uint64_t max_addr) 114 { 115 uint64_t lstart = 0, lend = 0; 116 int index, error, phandle, child; 117 118 const int num = fdt_num_mem_rsv(fdtbus_get_data()); 119 for (index = 0; index <= num; index++) { 120 uint64_t addr, size; 121 122 error = fdt_get_mem_rsv(fdtbus_get_data(), index, 123 &addr, &size); 124 if (error != 0) 125 continue; 126 if (lstart <= addr && addr <= lend) { 127 size -= (lend - addr); 128 addr = lend; 129 } 130 if (size == 0) 131 continue; 132 if (addr + size <= min_addr) 133 continue; 134 if (addr >= max_addr) 135 continue; 136 if (addr < min_addr) { 137 size -= (min_addr - addr); 138 addr = min_addr; 139 } 140 if (addr + size > max_addr) 141 size = max_addr - addr; 142 fdt_memory_remove_range(addr, size); 143 lstart = addr; 144 lend = addr + size; 145 } 146 147 /* 148 * "no-map" ranges defined in the /reserved-memory node 149 * must also be excluded. 150 */ 151 phandle = OF_finddevice("/reserved-memory"); 152 if (phandle != -1) { 153 for (child = OF_child(phandle); child; child = OF_peer(child)) { 154 bus_addr_t addr; 155 bus_size_t size; 156 157 if (!of_hasprop(child, "no-map")) 158 continue; 159 160 if (fdtbus_get_reg(child, 0, &addr, &size) != 0) 161 continue; 162 if (size == 0) 163 continue; 164 fdt_memory_remove_range(addr, size); 165 } 166 } 167 } 168 169 void 170 fdt_memory_add_range(uint64_t start, uint64_t size) 171 { 172 struct fdt_memory_range *mr, *prev, *cur, *tmp; 173 bool inserted = false; 174 175 mr = fdt_memory_range_alloc(); 176 if (mr == NULL) 177 return; 178 179 mr->mr_mem.start = start; 180 mr->mr_mem.end = start + size; 181 182 /* 183 * Add the new range to the list of sorted ranges. 184 */ 185 TAILQ_FOREACH(cur, &fdt_memory_ranges, mr_list) 186 if (mr->mr_mem.start <= cur->mr_mem.start) { 187 TAILQ_INSERT_BEFORE(cur, mr, mr_list); 188 inserted = true; 189 break; 190 } 191 if (!inserted) 192 TAILQ_INSERT_TAIL(&fdt_memory_ranges, mr, mr_list); 193 194 /* 195 * Remove overlaps. 196 */ 197 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 198 prev = TAILQ_PREV(mr, fdt_memory_rangehead, mr_list); 199 if (prev && prev->mr_mem.end > mr->mr_mem.start) { 200 mr->mr_mem.start = prev->mr_mem.end; 201 if (mr->mr_mem.start >= mr->mr_mem.end) { 202 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 203 fdt_memory_range_free(mr); 204 } 205 } 206 } 207 208 /* 209 * Combine adjacent ranges. 210 */ 211 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 212 prev = TAILQ_PREV(mr, fdt_memory_rangehead, mr_list); 213 if (prev && prev->mr_mem.end == mr->mr_mem.start) { 214 prev->mr_mem.end = mr->mr_mem.end; 215 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 216 fdt_memory_range_free(mr); 217 } 218 } 219 } 220 221 void 222 fdt_memory_remove_range(uint64_t start, uint64_t size) 223 { 224 struct fdt_memory_range *mr, *next, *tmp; 225 const uint64_t end = start + size; 226 227 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 228 if (start <= mr->mr_mem.start && end >= mr->mr_mem.end) { 229 /* 230 * Removed range completely covers this range, 231 * just remove it. 232 */ 233 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 234 fdt_memory_range_free(mr); 235 } else if (start > mr->mr_mem.start && end < mr->mr_mem.end) { 236 /* 237 * Removed range is completely contained by this range, 238 * split it. 239 */ 240 next = fdt_memory_range_alloc(); 241 if (next == NULL) 242 panic("fdt_memory_remove_range"); 243 next->mr_mem.start = end; 244 next->mr_mem.end = mr->mr_mem.end; 245 mr->mr_mem.end = start; 246 TAILQ_INSERT_AFTER(&fdt_memory_ranges, mr, next, mr_list); 247 } else if (start <= mr->mr_mem.start && end > mr->mr_mem.start && end < mr->mr_mem.end) { 248 /* 249 * Partial overlap at the beginning of the range. 250 */ 251 mr->mr_mem.start = end; 252 } else if (start > mr->mr_mem.start && start < mr->mr_mem.end && end >= mr->mr_mem.end) { 253 /* 254 * Partial overlap at the end of the range. 255 */ 256 mr->mr_mem.end = start; 257 } 258 KASSERT(mr->mr_mem.start < mr->mr_mem.end); 259 } 260 } 261 262 void 263 fdt_memory_foreach(void (*fn)(const struct fdt_memory *, void *), void *arg) 264 { 265 struct fdt_memory_range *mr; 266 267 TAILQ_FOREACH(mr, &fdt_memory_ranges, mr_list) 268 fn(&mr->mr_mem, arg); 269 } 270
Indexes created Tue Sep 23 07:09:52 GMT 2025