fdt_memory.c revision 1.8
1 /* $NetBSD: fdt_memory.c,v 1.8 2022/11/04 10:51:16 jmcneill 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 1.8 2022/11/04 10:51:16 jmcneill 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 struct fdt_memory_range { 45 struct fdt_memory mr_mem; 46 bool mr_used; 47 TAILQ_ENTRY(fdt_memory_range) mr_list; 48 }; 49 50 static TAILQ_HEAD(fdt_memory_rangehead, fdt_memory_range) fdt_memory_ranges = 51 TAILQ_HEAD_INITIALIZER(fdt_memory_ranges); 52 53 static struct fdt_memory_range fdt_memory_range_pool[FDT_MEMORY_RANGES]; 54 55 static struct fdt_memory_range * 56 fdt_memory_range_alloc(void) 57 { 58 for (size_t n = 0; n < FDT_MEMORY_RANGES; n++) 59 if (!fdt_memory_range_pool[n].mr_used) { 60 fdt_memory_range_pool[n].mr_used = true; 61 return &fdt_memory_range_pool[n]; 62 } 63 64 printf("%s: no free memory ranges, increase FDT_MEMORY_RANGES!\n", __func__); 65 return NULL; 66 } 67 68 static void 69 fdt_memory_range_free(struct fdt_memory_range *mr) 70 { 71 mr->mr_used = false; 72 } 73 74 /* 75 * Get all of physical memory, including holes. 76 */ 77 void 78 fdt_memory_get(uint64_t *pstart, uint64_t *pend) 79 { 80 const int memory = OF_finddevice("/memory"); 81 uint64_t cur_addr, cur_size; 82 int index, nadd; 83 84 for (index = 0, nadd = 0; 85 fdtbus_get_reg64(memory, index, &cur_addr, &cur_size) == 0; 86 index++) { 87 if (cur_size == 0) 88 continue; 89 fdt_memory_add_range(cur_addr, cur_size); 90 91 if (nadd++ == 0) { 92 *pstart = cur_addr; 93 *pend = cur_addr + cur_size; 94 continue; 95 } 96 if (cur_addr < *pstart) 97 *pstart = cur_addr; 98 if (cur_addr + cur_size > *pend) 99 *pend = cur_addr + cur_size; 100 } 101 if (nadd == 0) 102 panic("Cannot determine memory size"); 103 } 104 105 /* 106 * Exclude memory ranges from memory config from the device tree 107 */ 108 void 109 fdt_memory_remove_reserved(uint64_t min_addr, uint64_t max_addr) 110 { 111 uint64_t lstart = 0, lend = 0; 112 int index, error, phandle, child; 113 114 const int num = fdt_num_mem_rsv(fdtbus_get_data()); 115 for (index = 0; index <= num; index++) { 116 uint64_t addr, size; 117 118 error = fdt_get_mem_rsv(fdtbus_get_data(), index, 119 &addr, &size); 120 if (error != 0) 121 continue; 122 if (lstart <= addr && addr <= lend) { 123 size -= (lend - addr); 124 addr = lend; 125 } 126 if (size == 0) 127 continue; 128 if (addr + size <= min_addr) 129 continue; 130 if (addr >= max_addr) 131 continue; 132 if (addr < min_addr) { 133 size -= (min_addr - addr); 134 addr = min_addr; 135 } 136 if (addr + size > max_addr) 137 size = max_addr - addr; 138 fdt_memory_remove_range(addr, size); 139 lstart = addr; 140 lend = addr + size; 141 } 142 143 /* 144 * "no-map" ranges defined in the /reserved-memory node 145 * must also be excluded. 146 */ 147 phandle = OF_finddevice("/reserved-memory"); 148 if (phandle != -1) { 149 for (child = OF_child(phandle); child; child = OF_peer(child)) { 150 bus_addr_t addr; 151 bus_size_t size; 152 153 if (fdtbus_get_reg(child, 0, &addr, &size) != 0) 154 continue; 155 if (size == 0) 156 continue; 157 fdt_memory_remove_range(addr, size); 158 } 159 } 160 } 161 162 void 163 fdt_memory_add_range(uint64_t start, uint64_t size) 164 { 165 struct fdt_memory_range *mr, *prev, *cur, *tmp; 166 bool inserted = false; 167 168 mr = fdt_memory_range_alloc(); 169 if (mr == NULL) 170 return; 171 172 mr->mr_mem.start = start; 173 mr->mr_mem.end = start + size; 174 175 /* 176 * Add the new range to the list of sorted ranges. 177 */ 178 TAILQ_FOREACH(cur, &fdt_memory_ranges, mr_list) 179 if (mr->mr_mem.start <= cur->mr_mem.start) { 180 TAILQ_INSERT_BEFORE(cur, mr, mr_list); 181 inserted = true; 182 break; 183 } 184 if (!inserted) 185 TAILQ_INSERT_TAIL(&fdt_memory_ranges, mr, mr_list); 186 187 /* 188 * Remove overlaps. 189 */ 190 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 191 prev = TAILQ_PREV(mr, fdt_memory_rangehead, mr_list); 192 if (prev && prev->mr_mem.end > mr->mr_mem.start) { 193 mr->mr_mem.start = prev->mr_mem.end; 194 if (mr->mr_mem.start >= mr->mr_mem.end) { 195 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 196 fdt_memory_range_free(mr); 197 } 198 } 199 } 200 201 /* 202 * Combine adjacent ranges. 203 */ 204 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 205 prev = TAILQ_PREV(mr, fdt_memory_rangehead, mr_list); 206 if (prev && prev->mr_mem.end == mr->mr_mem.start) { 207 prev->mr_mem.end = mr->mr_mem.end; 208 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 209 fdt_memory_range_free(mr); 210 } 211 } 212 } 213 214 void 215 fdt_memory_remove_range(uint64_t start, uint64_t size) 216 { 217 struct fdt_memory_range *mr, *next, *tmp; 218 const uint64_t end = start + size; 219 220 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 221 if (start <= mr->mr_mem.start && end >= mr->mr_mem.end) { 222 /* 223 * Removed range completely covers this range, 224 * just remove it. 225 */ 226 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 227 fdt_memory_range_free(mr); 228 } else if (start > mr->mr_mem.start && end < mr->mr_mem.end) { 229 /* 230 * Removed range is completely contained by this range, 231 * split it. 232 */ 233 next = fdt_memory_range_alloc(); 234 if (next == NULL) 235 panic("fdt_memory_remove_range"); 236 next->mr_mem.start = end; 237 next->mr_mem.end = mr->mr_mem.end; 238 mr->mr_mem.end = start; 239 TAILQ_INSERT_AFTER(&fdt_memory_ranges, mr, next, mr_list); 240 } else if (start <= mr->mr_mem.start && end > mr->mr_mem.start && end < mr->mr_mem.end) { 241 /* 242 * Partial overlap at the beginning of the range. 243 */ 244 mr->mr_mem.start = end; 245 } else if (start > mr->mr_mem.start && start < mr->mr_mem.end && end >= mr->mr_mem.end) { 246 /* 247 * Partial overlap at the end of the range. 248 */ 249 mr->mr_mem.end = start; 250 } 251 KASSERT(mr->mr_mem.start < mr->mr_mem.end); 252 } 253 } 254 255 void 256 fdt_memory_foreach(void (*fn)(const struct fdt_memory *, void *), void *arg) 257 { 258 struct fdt_memory_range *mr; 259 260 TAILQ_FOREACH(mr, &fdt_memory_ranges, mr_list) 261 fn(&mr->mr_mem, arg); 262 } 263
Indexes created Tue Sep 30 20:09:53 GMT 2025