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e0709f50 | 1 | /* dv-nvram.c -- Generic driver for a non volatile ram (battery saved) |
ecd75fc8 | 2 | Copyright (C) 1999-2014 Free Software Foundation, Inc. |
e0709f50 AC |
3 | Written by Stephane Carrez (stcarrez@worldnet.fr) |
4 | (From a driver model Contributed by Cygnus Solutions.) | |
5 | ||
6 | This program is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
4744ac1b | 8 | the Free Software Foundation; either version 3 of the License, or |
e0709f50 | 9 | (at your option) any later version. |
4744ac1b | 10 | |
e0709f50 AC |
11 | This program is distributed in the hope that it will be useful, |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
4744ac1b | 15 | |
e0709f50 | 16 | You should have received a copy of the GNU General Public License |
4744ac1b | 17 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
e0709f50 AC |
18 | |
19 | */ | |
20 | ||
21 | ||
22 | #include "sim-main.h" | |
23 | #include "hw-main.h" | |
24 | #include "sim-assert.h" | |
25 | ||
26 | #include <unistd.h> | |
27 | #include <fcntl.h> | |
28 | #include <errno.h> | |
29 | ||
30 | ||
31 | /* DEVICE | |
32 | ||
33 | nvram - Non Volatile Ram | |
34 | ||
35 | ||
36 | DESCRIPTION | |
37 | ||
38 | Implements a generic battery saved CMOS ram. This ram device does | |
39 | not contain any realtime clock and does not generate any interrupt. | |
40 | The ram content is loaded from a file and saved when it is changed. | |
41 | It is intended to be generic. | |
42 | ||
43 | ||
44 | PROPERTIES | |
45 | ||
e0709f50 AC |
46 | reg <base> <length> |
47 | ||
48 | Base and size of the non-volatile ram bank. | |
49 | ||
50 | file <path> | |
51 | ||
52 | Path where the memory must be saved or loaded when we start. | |
53 | ||
54 | mode {map | save-modified | save-all} | |
55 | ||
56 | Controls how to load and save the memory content. | |
57 | ||
58 | map The file is mapped in memory | |
59 | save-modified The simulator keeps an open file descriptor to | |
60 | the file and saves portion of memory which are | |
61 | modified. | |
62 | save-all The simulator saves the complete memory each time | |
63 | it's modified (it does not keep an open file | |
64 | descriptor). | |
65 | ||
66 | ||
67 | PORTS | |
68 | ||
69 | None. | |
70 | ||
71 | ||
72 | NOTES | |
73 | ||
74 | This device is independent of the Motorola 68hc11. | |
75 | ||
76 | */ | |
77 | ||
78 | ||
79 | ||
80 | /* static functions */ | |
81 | ||
82 | /* Control of how to access the ram and save its content. */ | |
83 | ||
84 | enum nvram_mode | |
85 | { | |
86 | /* Save the complete ram block each time it's changed. | |
87 | We don't keep an open file descriptor. This should be | |
88 | ok for small memory banks. */ | |
89 | NVRAM_SAVE_ALL, | |
90 | ||
91 | /* Save only the memory bytes which are modified. | |
92 | This mode means that we have to keep an open file | |
93 | descriptor (O_RDWR). It's good for middle sized memory banks. */ | |
94 | NVRAM_SAVE_MODIFIED, | |
95 | ||
96 | /* Map file in memory (not yet implemented). | |
97 | This mode is suitable for large memory banks. We don't allocate | |
98 | a buffer to represent the ram, instead it's mapped in memory | |
99 | with mmap. */ | |
100 | NVRAM_MAP_FILE | |
101 | }; | |
102 | ||
103 | struct nvram | |
104 | { | |
105 | address_word base_address; /* Base address of ram. */ | |
106 | unsigned size; /* Size of ram. */ | |
107 | unsigned8 *data; /* Pointer to ram memory. */ | |
108 | const char *file_name; /* Path of ram file. */ | |
109 | int fd; /* File description of opened ram file. */ | |
110 | enum nvram_mode mode; /* How load/save ram file. */ | |
111 | }; | |
112 | ||
113 | ||
114 | ||
115 | /* Finish off the partially created hw device. Attach our local | |
116 | callbacks. Wire up our port names etc. */ | |
117 | ||
118 | static hw_io_read_buffer_method nvram_io_read_buffer; | |
119 | static hw_io_write_buffer_method nvram_io_write_buffer; | |
120 | ||
121 | ||
122 | ||
123 | static void | |
124 | attach_nvram_regs (struct hw *me, struct nvram *controller) | |
125 | { | |
126 | unsigned_word attach_address; | |
127 | int attach_space; | |
128 | unsigned attach_size; | |
129 | reg_property_spec reg; | |
130 | int result, oerrno; | |
131 | ||
e0709f50 AC |
132 | /* Get ram bank description (base and size). */ |
133 | if (hw_find_property (me, "reg") == NULL) | |
134 | hw_abort (me, "Missing \"reg\" property"); | |
135 | ||
136 | if (!hw_find_reg_array_property (me, "reg", 0, ®)) | |
137 | hw_abort (me, "\"reg\" property must contain one addr/size entry"); | |
138 | ||
139 | hw_unit_address_to_attach_address (hw_parent (me), | |
140 | ®.address, | |
141 | &attach_space, | |
142 | &attach_address, | |
143 | me); | |
144 | hw_unit_size_to_attach_size (hw_parent (me), | |
145 | ®.size, | |
146 | &attach_size, me); | |
147 | ||
148 | hw_attach_address (hw_parent (me), 0, | |
149 | attach_space, attach_address, attach_size, | |
150 | me); | |
151 | ||
152 | controller->mode = NVRAM_SAVE_ALL; | |
153 | controller->base_address = attach_address; | |
154 | controller->size = attach_size; | |
155 | controller->fd = -1; | |
156 | ||
157 | /* Get the file where the ram content must be loaded/saved. */ | |
158 | if(hw_find_property (me, "file") == NULL) | |
159 | hw_abort (me, "Missing \"file\" property"); | |
160 | ||
161 | controller->file_name = hw_find_string_property (me, "file"); | |
162 | ||
163 | /* Get the mode which defines how to save the memory. */ | |
164 | if(hw_find_property (me, "mode") != NULL) | |
165 | { | |
166 | const char *value = hw_find_string_property (me, "mode"); | |
167 | ||
168 | if (strcmp (value, "map") == 0) | |
169 | controller->mode = NVRAM_MAP_FILE; | |
170 | else if (strcmp (value, "save-modified") == 0) | |
171 | controller->mode = NVRAM_SAVE_MODIFIED; | |
172 | else if (strcmp (value, "save-all") == 0) | |
173 | controller->mode = NVRAM_SAVE_ALL; | |
174 | else | |
175 | hw_abort (me, "illegal value for mode parameter `%s': " | |
176 | "use map, save-modified or save-all", value); | |
177 | } | |
178 | ||
179 | /* Initialize the ram by loading/mapping the file in memory. | |
180 | If the file does not exist, create and give it some content. */ | |
181 | switch (controller->mode) | |
182 | { | |
183 | case NVRAM_MAP_FILE: | |
184 | hw_abort (me, "'map' mode is not yet implemented, use 'save-modified'"); | |
185 | break; | |
186 | ||
187 | case NVRAM_SAVE_MODIFIED: | |
188 | case NVRAM_SAVE_ALL: | |
6e73e7ed | 189 | controller->data = (char*) hw_malloc (me, attach_size); |
e0709f50 AC |
190 | if (controller->data == 0) |
191 | hw_abort (me, "Not enough memory, try to use the mode 'map'"); | |
192 | ||
193 | memset (controller->data, 0, attach_size); | |
194 | controller->fd = open (controller->file_name, O_RDWR); | |
195 | if (controller->fd < 0) | |
196 | { | |
197 | controller->fd = open (controller->file_name, | |
198 | O_RDWR | O_CREAT, 0644); | |
199 | if (controller->fd < 0) | |
200 | hw_abort (me, "Cannot open or create file '%s'", | |
201 | controller->file_name); | |
202 | result = write (controller->fd, controller->data, attach_size); | |
203 | if (result != attach_size) | |
204 | { | |
205 | oerrno = errno; | |
6e73e7ed | 206 | hw_free (me, controller->data); |
e0709f50 AC |
207 | close (controller->fd); |
208 | errno = oerrno; | |
209 | hw_abort (me, "Failed to save the ram content"); | |
210 | } | |
211 | } | |
212 | else | |
213 | { | |
214 | result = read (controller->fd, controller->data, attach_size); | |
215 | if (result != attach_size) | |
216 | { | |
217 | oerrno = errno; | |
6e73e7ed | 218 | hw_free (me, controller->data); |
e0709f50 AC |
219 | close (controller->fd); |
220 | errno = oerrno; | |
221 | hw_abort (me, "Failed to load the ram content"); | |
222 | } | |
223 | } | |
224 | if (controller->mode == NVRAM_SAVE_ALL) | |
225 | { | |
226 | close (controller->fd); | |
227 | controller->fd = -1; | |
228 | } | |
229 | break; | |
230 | ||
231 | default: | |
232 | break; | |
233 | } | |
234 | } | |
235 | ||
236 | ||
237 | static void | |
238 | nvram_finish (struct hw *me) | |
239 | { | |
240 | struct nvram *controller; | |
241 | ||
242 | controller = HW_ZALLOC (me, struct nvram); | |
243 | ||
244 | set_hw_data (me, controller); | |
245 | set_hw_io_read_buffer (me, nvram_io_read_buffer); | |
246 | set_hw_io_write_buffer (me, nvram_io_write_buffer); | |
247 | ||
248 | /* Attach ourself to our parent bus. */ | |
249 | attach_nvram_regs (me, controller); | |
250 | } | |
251 | ||
252 | ||
253 | ||
254 | /* generic read/write */ | |
255 | ||
256 | static unsigned | |
257 | nvram_io_read_buffer (struct hw *me, | |
258 | void *dest, | |
259 | int space, | |
260 | unsigned_word base, | |
261 | unsigned nr_bytes) | |
262 | { | |
263 | struct nvram *controller = hw_data (me); | |
264 | ||
265 | HW_TRACE ((me, "read 0x%08lx %d [%ld]", | |
266 | (long) base, (int) nr_bytes, | |
267 | (long) (base - controller->base_address))); | |
268 | ||
269 | base -= controller->base_address; | |
270 | if (base + nr_bytes > controller->size) | |
271 | nr_bytes = controller->size - base; | |
272 | ||
273 | memcpy (dest, &controller->data[base], nr_bytes); | |
274 | return nr_bytes; | |
275 | } | |
276 | ||
277 | ||
278 | ||
279 | static unsigned | |
280 | nvram_io_write_buffer (struct hw *me, | |
281 | const void *source, | |
282 | int space, | |
283 | unsigned_word base, | |
284 | unsigned nr_bytes) | |
285 | { | |
286 | struct nvram *controller = hw_data (me); | |
287 | ||
288 | HW_TRACE ((me, "write 0x%08lx %d [%ld]", | |
289 | (long) base, (int) nr_bytes, | |
290 | (long) (base - controller->base_address))); | |
291 | ||
292 | base -= controller->base_address; | |
293 | if (base + nr_bytes > controller->size) | |
294 | nr_bytes = controller->size - base; | |
295 | ||
296 | switch (controller->mode) | |
297 | { | |
298 | case NVRAM_SAVE_ALL: | |
299 | { | |
300 | int fd, result, oerrno; | |
301 | ||
302 | fd = open (controller->file_name, O_WRONLY, 0644); | |
303 | if (fd < 0) | |
304 | { | |
305 | return 0; | |
306 | } | |
307 | ||
308 | memcpy (&controller->data[base], source, nr_bytes); | |
309 | result = write (fd, controller->data, controller->size); | |
310 | oerrno = errno; | |
311 | close (fd); | |
312 | errno = oerrno; | |
313 | ||
314 | if (result != controller->size) | |
315 | { | |
316 | return 0; | |
317 | } | |
318 | return nr_bytes; | |
319 | } | |
320 | ||
321 | case NVRAM_SAVE_MODIFIED: | |
322 | { | |
323 | off_t pos; | |
324 | int result; | |
325 | ||
326 | pos = lseek (controller->fd, (off_t) base, SEEK_SET); | |
327 | if (pos != (off_t) base) | |
328 | return 0; | |
329 | ||
330 | result = write (controller->fd, source, nr_bytes); | |
331 | if (result < 0) | |
332 | return 0; | |
333 | ||
334 | nr_bytes = result; | |
335 | break; | |
336 | } | |
337 | ||
338 | default: | |
339 | break; | |
340 | } | |
341 | memcpy (&controller->data[base], source, nr_bytes); | |
342 | return nr_bytes; | |
343 | } | |
344 | ||
345 | ||
346 | const struct hw_descriptor dv_nvram_descriptor[] = { | |
347 | { "nvram", nvram_finish, }, | |
348 | { NULL }, | |
349 | }; | |
350 |