summaryrefslogtreecommitdiff
path: root/arch/sandbox/cpu/state.c
blob: d2a7dc9b450f8845811c9575a5731b0557c959c0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
/*
 * Copyright (c) 2011-2012 The Chromium OS Authors.
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <errno.h>
#include <fdtdec.h>
#include <os.h>
#include <asm/state.h>

/* Main state record for the sandbox */
static struct sandbox_state main_state;
static struct sandbox_state *state;	/* Pointer to current state record */

static int state_ensure_space(int extra_size)
{
	void *blob = state->state_fdt;
	int used, size, free;
	void *buf;
	int ret;

	used = fdt_off_dt_strings(blob) + fdt_size_dt_strings(blob);
	size = fdt_totalsize(blob);
	free = size - used;
	if (free > extra_size)
		return 0;

	size = used + extra_size;
	buf = os_malloc(size);
	if (!buf)
		return -ENOMEM;

	ret = fdt_open_into(blob, buf, size);
	if (ret) {
		os_free(buf);
		return -EIO;
	}

	os_free(blob);
	state->state_fdt = buf;
	return 0;
}

static int state_read_file(struct sandbox_state *state, const char *fname)
{
	loff_t size;
	int ret;
	int fd;

	ret = os_get_filesize(fname, &size);
	if (ret < 0) {
		printf("Cannot find sandbox state file '%s'\n", fname);
		return -ENOENT;
	}
	state->state_fdt = os_malloc(size);
	if (!state->state_fdt) {
		puts("No memory to read sandbox state\n");
		return -ENOMEM;
	}
	fd = os_open(fname, OS_O_RDONLY);
	if (fd < 0) {
		printf("Cannot open sandbox state file '%s'\n", fname);
		ret = -EPERM;
		goto err_open;
	}
	if (os_read(fd, state->state_fdt, size) != size) {
		printf("Cannot read sandbox state file '%s'\n", fname);
		ret = -EIO;
		goto err_read;
	}
	os_close(fd);

	return 0;
err_read:
	os_close(fd);
err_open:
	os_free(state->state_fdt);
	state->state_fdt = NULL;

	return ret;
}

/***
 * sandbox_read_state_nodes() - Read state associated with a driver
 *
 * This looks through all compatible nodes and calls the read function on
 * each one, to read in the state.
 *
 * If nothing is found, it still calls the read function once, to set up a
 * single global state for that driver.
 *
 * @state: Sandbox state
 * @io: Method to use for reading state
 * @blob: FDT containing state
 * @return 0 if OK, -EINVAL if the read function returned failure
 */
int sandbox_read_state_nodes(struct sandbox_state *state,
			     struct sandbox_state_io *io, const void *blob)
{
	int count;
	int node;
	int ret;

	debug("   - read %s\n", io->name);
	if (!io->read)
		return 0;

	node = -1;
	count = 0;
	while (blob) {
		node = fdt_node_offset_by_compatible(blob, node, io->compat);
		if (node < 0)
			return 0;	/* No more */
		debug("   - read node '%s'\n", fdt_get_name(blob, node, NULL));
		ret = io->read(blob, node);
		if (ret) {
			printf("Unable to read state for '%s'\n", io->compat);
			return -EINVAL;
		}
		count++;
	}

	/*
	 * If we got no saved state, call the read function once without a
	 * node, to set up the global state.
	 */
	if (count == 0) {
		debug("   - read global\n");
		ret = io->read(NULL, -1);
		if (ret) {
			printf("Unable to read global state for '%s'\n",
			       io->name);
			return -EINVAL;
		}
	}

	return 0;
}

int sandbox_read_state(struct sandbox_state *state, const char *fname)
{
	struct sandbox_state_io *io;
	const void *blob;
	bool got_err;
	int ret;

	if (state->read_state && fname) {
		ret = state_read_file(state, fname);
		if (ret == -ENOENT && state->ignore_missing_state_on_read)
			ret = 0;
		if (ret)
			return ret;
	}

	/* Call all the state read funtcions */
	got_err = false;
	blob = state->state_fdt;
	io = ll_entry_start(struct sandbox_state_io, state_io);
	for (; io < ll_entry_end(struct sandbox_state_io, state_io); io++) {
		ret = sandbox_read_state_nodes(state, io, blob);
		if (ret < 0)
			got_err = true;
	}

	if (state->read_state && fname) {
		debug("Read sandbox state from '%s'%s\n", fname,
		      got_err ? " (with errors)" : "");
	}

	return got_err ? -1 : 0;
}

/***
 * sandbox_write_state_node() - Write state associated with a driver
 *
 * This calls the write function to write out global state for that driver.
 *
 * TODO(sjg@chromium.org): Support writing out state from multiple drivers
 * of the same time. We don't need this yet,and it will be much easier to
 * do when driver model is available.
 *
 * @state: Sandbox state
 * @io: Method to use for writing state
 * @return 0 if OK, -EIO if there is a fatal error (such as out of space
 * for adding the data), -EINVAL if the write function failed.
 */
int sandbox_write_state_node(struct sandbox_state *state,
			     struct sandbox_state_io *io)
{
	void *blob;
	int node;
	int ret;

	if (!io->write)
		return 0;

	ret = state_ensure_space(SANDBOX_STATE_MIN_SPACE);
	if (ret) {
		printf("Failed to add more space for state\n");
		return -EIO;
	}

	/* The blob location can change when the size increases */
	blob = state->state_fdt;
	node = fdt_node_offset_by_compatible(blob, -1, io->compat);
	if (node == -FDT_ERR_NOTFOUND) {
		node = fdt_add_subnode(blob, 0, io->name);
		if (node < 0) {
			printf("Cannot create node '%s': %s\n", io->name,
			       fdt_strerror(node));
			return -EIO;
		}

		if (fdt_setprop_string(blob, node, "compatible", io->compat)) {
			puts("Cannot set compatible\n");
			return -EIO;
		}
	} else if (node < 0) {
		printf("Cannot access node '%s': %s\n", io->name,
		       fdt_strerror(node));
		return -EIO;
	}
	debug("Write state for '%s' to node %d\n", io->compat, node);
	ret = io->write(blob, node);
	if (ret) {
		printf("Unable to write state for '%s'\n", io->compat);
		return -EINVAL;
	}

	return 0;
}

int sandbox_write_state(struct sandbox_state *state, const char *fname)
{
	struct sandbox_state_io *io;
	bool got_err;
	int size;
	int ret;
	int fd;

	/* Create a state FDT if we don't have one */
	if (!state->state_fdt) {
		size = 0x4000;
		state->state_fdt = os_malloc(size);
		if (!state->state_fdt) {
			puts("No memory to create FDT\n");
			return -ENOMEM;
		}
		ret = fdt_create_empty_tree(state->state_fdt, size);
		if (ret < 0) {
			printf("Cannot create empty state FDT: %s\n",
			       fdt_strerror(ret));
			ret = -EIO;
			goto err_create;
		}
	}

	/* Call all the state write funtcions */
	got_err = false;
	io = ll_entry_start(struct sandbox_state_io, state_io);
	ret = 0;
	for (; io < ll_entry_end(struct sandbox_state_io, state_io); io++) {
		ret = sandbox_write_state_node(state, io);
		if (ret == -EIO)
			break;
		else if (ret)
			got_err = true;
	}

	if (ret == -EIO) {
		printf("Could not write sandbox state\n");
		goto err_create;
	}

	ret = fdt_pack(state->state_fdt);
	if (ret < 0) {
		printf("Cannot pack state FDT: %s\n", fdt_strerror(ret));
		ret = -EINVAL;
		goto err_create;
	}
	size = fdt_totalsize(state->state_fdt);
	fd = os_open(fname, OS_O_WRONLY | OS_O_CREAT);
	if (fd < 0) {
		printf("Cannot open sandbox state file '%s'\n", fname);
		ret = -EIO;
		goto err_create;
	}
	if (os_write(fd, state->state_fdt, size) != size) {
		printf("Cannot write sandbox state file '%s'\n", fname);
		ret = -EIO;
		goto err_write;
	}
	os_close(fd);

	debug("Wrote sandbox state to '%s'%s\n", fname,
	      got_err ? " (with errors)" : "");

	return 0;
err_write:
	os_close(fd);
err_create:
	os_free(state->state_fdt);

	return ret;
}

int state_setprop(int node, const char *prop_name, const void *data, int size)
{
	void *blob;
	int len;
	int ret;

	fdt_getprop(state->state_fdt, node, prop_name, &len);

	/* Add space for the new property, its name and some overhead */
	ret = state_ensure_space(size - len + strlen(prop_name) + 32);
	if (ret)
		return ret;

	/* This should succeed, barring a mutiny */
	blob = state->state_fdt;
	ret = fdt_setprop(blob, node, prop_name, data, size);
	if (ret) {
		printf("%s: Unable to set property '%s' in node '%s': %s\n",
		       __func__, prop_name, fdt_get_name(blob, node, NULL),
			fdt_strerror(ret));
		return -ENOSPC;
	}

	return 0;
}

struct sandbox_state *state_get_current(void)
{
	assert(state);
	return state;
}

void state_set_skip_delays(bool skip_delays)
{
	struct sandbox_state *state = state_get_current();

	state->skip_delays = skip_delays;
}

bool state_get_skip_delays(void)
{
	struct sandbox_state *state = state_get_current();

	return state->skip_delays;
}

int state_init(void)
{
	state = &main_state;

	state->ram_size = CONFIG_SYS_SDRAM_SIZE;
	state->ram_buf = os_malloc(state->ram_size);
	assert(state->ram_buf);

	/* No reset yet, so mark it as such. Always allow power reset */
	state->last_reset = RESET_COUNT;
	state->reset_allowed[RESET_POWER] = true;

	/*
	 * Example of how to use GPIOs:
	 *
	 * sandbox_gpio_set_direction(170, 0);
	 * sandbox_gpio_set_value(170, 0);
	 */
	return 0;
}

int state_uninit(void)
{
	int err;

	state = &main_state;

	if (state->write_ram_buf && !state->ram_buf_rm) {
		err = os_write_ram_buf(state->ram_buf_fname);
		if (err) {
			printf("Failed to write RAM buffer\n");
			return err;
		}
	}

	if (state->write_state) {
		if (sandbox_write_state(state, state->state_fname)) {
			printf("Failed to write sandbox state\n");
			return -1;
		}
	}

	/* Delete this at the last moment so as not to upset gdb too much */
	if (state->jumped_fname)
		os_unlink(state->jumped_fname);

	if (state->state_fdt)
		os_free(state->state_fdt);
	memset(state, '\0', sizeof(*state));

	return 0;
}