xref: /netbsd-src/sys/dev/fdt/fdt_memory.c (revision 08dd5822d831b9cf9fc1ec25c2d00b0540b0835d)
1 /* $NetBSD: fdt_memory.c,v 1.10 2024/01/14 07:53:38 mlelstv 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@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 1.10 2024/01/14 07:53:38 mlelstv 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 *
fdt_memory_range_alloc(void)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
fdt_memory_range_free(struct fdt_memory_range * mr)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
fdt_memory_get(uint64_t * pstart,uint64_t * pend)78 fdt_memory_get(uint64_t *pstart, uint64_t *pend)
79 {
80 	const void *fdt_data = fdtbus_get_data();
81 	uint64_t cur_addr, cur_size;
82 	int index, nadd = 0, off, memory;
83 
84 	off = fdt_node_offset_by_prop_value(fdt_data, -1,
85 	    "device_type", "memory", sizeof("memory"));
86 
87 	/*
88 	 * Device Tree Specification 3.2 says that memory
89 	 * nodes are named "memory" and have device_type
90 	 * "memory", but if the device_type is missing, try
91 	 * to find the (then single) node by name.
92 	 */
93 	if (off == -FDT_ERR_NOTFOUND)
94 		off = fdt_path_offset(fdt_data, "/memory");
95 
96 	while (off != -FDT_ERR_NOTFOUND) {
97 		memory = fdtbus_offset2phandle(off);
98 		for (index = 0;
99 		     fdtbus_get_reg64(memory, index, &cur_addr, &cur_size) == 0;
100 		     index++) {
101 			if (cur_size == 0)
102 				continue;
103 			fdt_memory_add_range(cur_addr, cur_size);
104 
105 			if (nadd++ == 0) {
106 				*pstart = cur_addr;
107 				*pend = cur_addr + cur_size;
108 				continue;
109 			}
110 			if (cur_addr < *pstart)
111 				*pstart = cur_addr;
112 			if (cur_addr + cur_size > *pend)
113 				*pend = cur_addr + cur_size;
114 		}
115 		off = fdt_node_offset_by_prop_value(fdt_data, off,
116 		    "device_type", "memory", sizeof("memory"));
117 	}
118 	if (nadd == 0)
119 		panic("Cannot determine memory size");
120 }
121 
122 /*
123  * Exclude memory ranges from memory config from the device tree
124  */
125 void
fdt_memory_remove_reserved(uint64_t min_addr,uint64_t max_addr)126 fdt_memory_remove_reserved(uint64_t min_addr, uint64_t max_addr)
127 {
128 	uint64_t lstart = 0, lend = 0;
129 	int index, error, phandle, child;
130 	const void *fdt_data = fdtbus_get_data();
131 	const int num = fdt_num_mem_rsv(fdt_data);
132 
133 	for (index = 0; index <= num; index++) {
134 		uint64_t addr, size;
135 
136 		error = fdt_get_mem_rsv(fdt_data, index, &addr, &size);
137 		if (error != 0)
138 			continue;
139 
140 		if (lstart <= addr && addr <= lend) {
141 			size -= (lend - addr);
142 			addr = lend;
143 		}
144 		if (size == 0)
145 			continue;
146 		if (addr + size <= min_addr)
147 			continue;
148 		if (addr >= max_addr)
149 			continue;
150 		if (addr < min_addr) {
151 			size -= (min_addr - addr);
152 			addr = min_addr;
153 		}
154 		if (addr + size > max_addr)
155 			size = max_addr - addr;
156 		fdt_memory_remove_range(addr, size);
157 		lstart = addr;
158 		lend = addr + size;
159 	}
160 
161 	/*
162 	 * "no-map" ranges defined in the /reserved-memory node
163 	 * must also be excluded.
164 	 */
165 	phandle = OF_finddevice("/reserved-memory");
166 	if (phandle != -1) {
167 		for (child = OF_child(phandle); child; child = OF_peer(child)) {
168 			bus_addr_t addr;
169 			bus_size_t size;
170 
171 			if (fdtbus_get_reg(child, 0, &addr, &size) != 0)
172 				continue;
173 			if (size == 0)
174 				continue;
175 			fdt_memory_remove_range(addr, size);
176 		}
177 	}
178 }
179 
180 void
fdt_memory_add_range(uint64_t start,uint64_t size)181 fdt_memory_add_range(uint64_t start, uint64_t size)
182 {
183 	struct fdt_memory_range *mr, *prev, *cur, *tmp;
184 	bool inserted = false;
185 
186 	mr = fdt_memory_range_alloc();
187 	if (mr == NULL)
188 		return;
189 
190 	mr->mr_mem.start = start;
191 	mr->mr_mem.end = start + size;
192 
193 	/*
194 	 * Add the new range to the list of sorted ranges.
195 	 */
196 	TAILQ_FOREACH(cur, &fdt_memory_ranges, mr_list)
197 		if (mr->mr_mem.start <= cur->mr_mem.start) {
198 			TAILQ_INSERT_BEFORE(cur, mr, mr_list);
199 			inserted = true;
200 			break;
201 		}
202 	if (!inserted)
203 		TAILQ_INSERT_TAIL(&fdt_memory_ranges, mr, mr_list);
204 
205 	/*
206 	 * Remove overlaps.
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 			mr->mr_mem.start = prev->mr_mem.end;
212 			if (mr->mr_mem.start >= mr->mr_mem.end) {
213 				TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list);
214 				fdt_memory_range_free(mr);
215 			}
216 		}
217 	}
218 
219 	/*
220 	 * Combine adjacent ranges.
221 	 */
222 	TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) {
223 		prev = TAILQ_PREV(mr, fdt_memory_rangehead, mr_list);
224 		if (prev && prev->mr_mem.end == mr->mr_mem.start) {
225 			prev->mr_mem.end = mr->mr_mem.end;
226 			TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list);
227 			fdt_memory_range_free(mr);
228 		}
229 	}
230 }
231 
232 void
fdt_memory_remove_range(uint64_t start,uint64_t size)233 fdt_memory_remove_range(uint64_t start, uint64_t size)
234 {
235 	struct fdt_memory_range *mr, *next, *tmp;
236 	const uint64_t end = start + size;
237 
238 	TAILQ_FOREACH_SAFE(mr, &fdt_memory_ranges, mr_list, tmp) {
239 		if (start <= mr->mr_mem.start && end >= mr->mr_mem.end) {
240 			/*
241 			 * Removed range completely covers this range,
242 			 * just remove it.
243 			 */
244 			TAILQ_REMOVE(&fdt_memory_ranges, mr, mr_list);
245 			fdt_memory_range_free(mr);
246 		} else if (start > mr->mr_mem.start && end < mr->mr_mem.end) {
247 			/*
248 			 * Removed range is completely contained by this range,
249 			 * split it.
250 			 */
251 			next = fdt_memory_range_alloc();
252 			if (next == NULL)
253 				panic("fdt_memory_remove_range");
254 			next->mr_mem.start = end;
255 			next->mr_mem.end = mr->mr_mem.end;
256 			mr->mr_mem.end = start;
257 			TAILQ_INSERT_AFTER(&fdt_memory_ranges, mr, next, mr_list);
258 		} else if (start <= mr->mr_mem.start && end > mr->mr_mem.start && end < mr->mr_mem.end) {
259 			/*
260 			 * Partial overlap at the beginning of the range.
261 			 */
262 			mr->mr_mem.start = end;
263 		} else if (start > mr->mr_mem.start && start < mr->mr_mem.end && end >= mr->mr_mem.end) {
264 			/*
265 			 * Partial overlap at the end of the range.
266 			 */
267 			mr->mr_mem.end = start;
268 		}
269 		KASSERT(mr->mr_mem.start < mr->mr_mem.end);
270 	}
271 }
272 
273 void
fdt_memory_foreach(void (* fn)(const struct fdt_memory *,void *),void * arg)274 fdt_memory_foreach(void (*fn)(const struct fdt_memory *, void *), void *arg)
275 {
276 	struct fdt_memory_range *mr;
277 
278 	TAILQ_FOREACH(mr, &fdt_memory_ranges, mr_list)
279 		fn(&mr->mr_mem, arg);
280 }
281