fdt_memory.c revision 1.1.6.1
1 /* $NetBSD: fdt_memory.c,v 1.1.6.1 2021/08/01 22:42:22 thorpej 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 1.1.6.1 2021/08/01 22:42:22 thorpej 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; 87 88 for (index = 0; 89 fdtbus_get_reg64(memory, index, &cur_addr, &cur_size) == 0; 90 index++) { 91 fdt_memory_add_range(cur_addr, cur_size); 92 93 /* Assume the first entry is the start of memory */ 94 if (index == 0) { 95 *pstart = cur_addr; 96 *pend = cur_addr + cur_size; 97 continue; 98 } 99 if (cur_addr + cur_size > *pend) 100 *pend = cur_addr + cur_size; 101 } 102 if (index == 0) 103 panic("Cannot determine memory size"); 104 } 105 106 /* 107 * Exclude memory ranges from memory config from the device tree 108 */ 109 void 110 fdt_memory_remove_reserved(uint64_t min_addr, uint64_t max_addr) 111 { 112 uint64_t lstart = 0, lend = 0; 113 int index, error, phandle, child; 114 115 const int num = fdt_num_mem_rsv(fdtbus_get_data()); 116 for (index = 0; index <= num; index++) { 117 uint64_t addr, size; 118 119 error = fdt_get_mem_rsv(fdtbus_get_data(), index, 120 &addr, &size); 121 if (error != 0) 122 continue; 123 if (lstart <= addr && addr <= lend) { 124 size -= (lend - addr); 125 addr = lend; 126 } 127 if (size == 0) 128 continue; 129 if (addr + size <= min_addr) 130 continue; 131 if (addr >= max_addr) 132 continue; 133 if (addr < min_addr) { 134 size -= (min_addr - addr); 135 addr = min_addr; 136 } 137 if (addr + size > max_addr) 138 size = max_addr - addr; 139 fdt_memory_remove_range(addr, size); 140 lstart = addr; 141 lend = addr + size; 142 } 143 144 /* 145 * "no-map" ranges defined in the /reserved-memory node 146 * must also be excluded. 147 */ 148 phandle = OF_finddevice("/reserved-memory"); 149 if (phandle != -1) { 150 for (child = OF_child(phandle); child; child = OF_peer(child)) { 151 bus_addr_t addr; 152 bus_size_t size; 153 154 if (!of_hasprop(child, "no-map")) 155 continue; 156 157 if (fdtbus_get_reg(child, 0, &addr, &size) != 0) 158 continue; 159 if (size == 0) 160 continue; 161 fdt_memory_remove_range(addr, size); 162 } 163 } 164 } 165 166 void 167 fdt_memory_add_range(uint64_t start, uint64_t size) 168 { 169 struct fdt_memory_range *mr, *prev, *cur, *tmp; 170 bool inserted = false; 171 172 mr = fdt_memory_range_alloc(); 173 if (mr == NULL) 174 return; 175 176 mr->mr_mem.start = start; 177 mr->mr_mem.end = start + size; 178 179 /* 180 * Add the new range to the list of sorted ranges. 181 */ 182 TAILQ_FOREACH(cur, &fdt_memory_ranges, mr_list) 183 if (mr->mr_mem.start <= cur->mr_mem.start) { 184 TAILQ_INSERT_BEFORE(cur, mr, mr_list); 185 inserted = true; 186 break; 187 } 188 if (!inserted) 189 TAILQ_INSERT_TAIL(&fdt_memory_ranges, mr, mr_list); 190 191 /* 192 * Remove overlaps. 193 */ 194 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 195 prev = TAILQ_PREV(mr, fdt_memory_rangehead, mr_list); 196 if (prev && prev->mr_mem.end > mr->mr_mem.start) { 197 mr->mr_mem.start = prev->mr_mem.end; 198 if (mr->mr_mem.start >= mr->mr_mem.end) { 199 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 200 fdt_memory_range_free(mr); 201 } 202 } 203 } 204 205 /* 206 * Combine adjacent ranges. 207 */ 208 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 209 prev = TAILQ_PREV(mr, fdt_memory_rangehead, mr_list); 210 if (prev && prev->mr_mem.end == mr->mr_mem.start) { 211 prev->mr_mem.end = mr->mr_mem.end; 212 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 213 fdt_memory_range_free(mr); 214 } 215 } 216 } 217 218 void 219 fdt_memory_remove_range(uint64_t start, uint64_t size) 220 { 221 struct fdt_memory_range *mr, *next, *tmp; 222 const uint64_t end = start + size; 223 224 TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) { 225 if (start <= mr->mr_mem.start && end >= mr->mr_mem.end) { 226 /* 227 * Removed range completely covers this range, 228 * just remove it. 229 */ 230 TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list); 231 fdt_memory_range_free(mr); 232 } else if (start > mr->mr_mem.start && end < mr->mr_mem.end) { 233 /* 234 * Removed range is completely contained by this range, 235 * split it. 236 */ 237 next = fdt_memory_range_alloc(); 238 if (next == NULL) 239 panic("fdt_memory_remove_range"); 240 next->mr_mem.start = end; 241 next->mr_mem.end = mr->mr_mem.end; 242 mr->mr_mem.end = start; 243 TAILQ_INSERT_AFTER(&fdt_memory_ranges, mr, next, mr_list); 244 } else if (start <= mr->mr_mem.start && end > mr->mr_mem.start && end < mr->mr_mem.end) { 245 /* 246 * Partial overlap at the beginning of the range. 247 */ 248 mr->mr_mem.start = end; 249 } else if (start > mr->mr_mem.start && start < mr->mr_mem.end && end >= mr->mr_mem.end) { 250 /* 251 * Partial overlap at the end of the range. 252 */ 253 mr->mr_mem.end = start; 254 } 255 KASSERT(mr->mr_mem.start < mr->mr_mem.end); 256 } 257 } 258 259 void 260 fdt_memory_foreach(void (*fn)(const struct fdt_memory *, void *), void *arg) 261 { 262 struct fdt_memory_range *mr; 263 264 TAILQ_FOREACH(mr, &fdt_memory_ranges, mr_list) 265 fn(&mr->mr_mem, arg); 266 } 267
Indexes created Tue Sep 30 20:09:53 GMT 2025