aboutsummaryrefslogtreecommitdiff
path: root/drivers/st/io/io_stm32image.c
blob: e6798e04799ecd946f85f3b81115e365013b7ff7 (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
/*
 * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <assert.h>
#include <boot_api.h>
#include <debug.h>
#include <errno.h>
#include <io_driver.h>
#include <io_stm32image.h>
#include <io_storage.h>
#include <platform.h>
#include <platform_def.h>
#include <stdint.h>
#include <string.h>
#include <utils.h>

static uintptr_t backend_dev_handle;
static uintptr_t backend_image_spec;
static uint32_t *stm32_img;
static uint8_t first_lba_buffer[MAX_LBA_SIZE] __aligned(4);
static struct stm32image_part_info *current_part;

/* STM32 Image driver functions */
static int stm32image_dev_open(const uintptr_t init_params,
			       io_dev_info_t **dev_info);
static int stm32image_partition_open(io_dev_info_t *dev_info,
				     const uintptr_t spec, io_entity_t *entity);
static int stm32image_partition_size(io_entity_t *entity, size_t *length);
static int stm32image_partition_read(io_entity_t *entity, uintptr_t buffer,
				     size_t length, size_t *length_read);
static int stm32image_partition_close(io_entity_t *entity);
static int stm32image_dev_init(io_dev_info_t *dev_info,
			       const uintptr_t init_params);
static int stm32image_dev_close(io_dev_info_t *dev_info);

/* Identify the device type as a virtual driver */
static io_type_t device_type_stm32image(void)
{
	return IO_TYPE_STM32IMAGE;
}

static const io_dev_connector_t stm32image_dev_connector = {
	.dev_open = stm32image_dev_open
};

static const io_dev_funcs_t stm32image_dev_funcs = {
	.type = device_type_stm32image,
	.open = stm32image_partition_open,
	.size = stm32image_partition_size,
	.read = stm32image_partition_read,
	.close = stm32image_partition_close,
	.dev_init = stm32image_dev_init,
	.dev_close = stm32image_dev_close,
};

static io_dev_info_t stm32image_dev_info = {
	.funcs = &stm32image_dev_funcs,
	.info = (uintptr_t)0,
};

static struct stm32image_device_info stm32image_dev;

static int get_part_idx_by_binary_type(uint32_t binary_type)
{
	int i;

	for (i = 0; i < STM32_PART_NUM; i++) {
		if (stm32image_dev.part_info[i].binary_type == binary_type) {
			return i;
		}
	}

	return -EINVAL;
}

/* Open a connection to the STM32IMAGE device */
static int stm32image_dev_open(const uintptr_t init_params,
			       io_dev_info_t **dev_info)
{
	int i;
	struct stm32image_device_info *device_info =
		(struct stm32image_device_info *)init_params;

	assert(dev_info != NULL);
	*dev_info = (io_dev_info_t *)&stm32image_dev_info;

	stm32image_dev.device_size = device_info->device_size;
	stm32image_dev.lba_size = device_info->lba_size;

	for (i = 0; i < STM32_PART_NUM; i++) {
		memcpy(stm32image_dev.part_info[i].name,
		       device_info->part_info[i].name, MAX_PART_NAME_SIZE);
		stm32image_dev.part_info[i].part_offset =
			device_info->part_info[i].part_offset;
		stm32image_dev.part_info[i].bkp_offset =
			device_info->part_info[i].bkp_offset;
	}

	return 0;
}

/* Do some basic package checks */
static int stm32image_dev_init(io_dev_info_t *dev_info,
			       const uintptr_t init_params)
{
	int result;

	if ((backend_dev_handle != 0U) || (backend_image_spec != 0U)) {
		ERROR("STM32 Image io supports only one session\n");
		return -ENOMEM;
	}

	/* Obtain a reference to the image by querying the platform layer */
	result = plat_get_image_source(STM32_IMAGE_ID, &backend_dev_handle,
				       &backend_image_spec);
	if (result != 0) {
		ERROR("STM32 image error (%i)\n", result);
		return -EINVAL;
	}

	return result;
}

/* Close a connection to the STM32 Image device */
static int stm32image_dev_close(io_dev_info_t *dev_info)
{
	backend_dev_handle = 0U;
	backend_image_spec = 0U;
	stm32_img = NULL;

	return 0;
}

/* Open a partition */
static int stm32image_partition_open(io_dev_info_t *dev_info,
				     const uintptr_t spec, io_entity_t *entity)
{
	const struct stm32image_part_info *partition_spec;
	int idx;

	assert(entity != NULL);

	partition_spec = (struct stm32image_part_info *)spec;
	assert(partition_spec != NULL);

	idx = get_part_idx_by_binary_type(partition_spec->binary_type);
	if ((idx < 0) || (idx > STM32_PART_NUM)) {
		ERROR("Wrong partition index (%d)\n", idx);
		return -EINVAL;
	}

	current_part = &stm32image_dev.part_info[idx];
	stm32_img = (uint32_t *)&current_part->part_offset;

	return 0;
}

/* Return the size of a partition */
static int stm32image_partition_size(io_entity_t *entity, size_t *length)
{
	int result;
	uintptr_t backend_handle;
	size_t bytes_read;
	boot_api_image_header_t *header =
		(boot_api_image_header_t *)first_lba_buffer;

	assert(entity != NULL);
	assert(length != NULL);

	/* Attempt to access the image */
	result = io_open(backend_dev_handle, backend_image_spec,
			 &backend_handle);

	if (result < 0) {
		ERROR("%s: io_open (%i)\n", __func__, result);
		return result;
	}

	/* Reset magic header value */
	header->magic = 0;

	while (header->magic == 0U) {
		result = io_seek(backend_handle, IO_SEEK_SET, *stm32_img);
		if (result != 0) {
			ERROR("%s: io_seek (%i)\n", __func__, result);
			break;
		}

		result = io_read(backend_handle, (uintptr_t)header,
				 MAX_LBA_SIZE, (size_t *)&bytes_read);
		if (result != 0) {
			ERROR("%s: io_read (%i)\n", __func__, result);
			break;
		}

		if ((header->magic != BOOT_API_IMAGE_HEADER_MAGIC_NB) ||
		    (header->binary_type != current_part->binary_type) ||
		    (header->image_length >= stm32image_dev.device_size)) {
			WARN("%s: partition %s wrong header\n",
			     __func__, current_part->name);

			/* Header not correct, check next offset for backup */
			*stm32_img += current_part->bkp_offset;
			if (*stm32_img > stm32image_dev.device_size) {
				/* No backup found, end of device reached */
				WARN("Out of memory\n");
				result = -ENOMEM;
				break;
			}
			header->magic = 0;
		}
	}

	io_close(backend_handle);

	if (result != 0) {
		return result;
	}

	*length = header->image_length;

	INFO("STM32 Image size : %i\n", *length);

	return 0;
}

static int check_header(boot_api_image_header_t *header, uintptr_t buffer)
{
	uint32_t i;
	uint32_t img_checksum = 0;

	/*
	 * Check header/payload validity:
	 *	- Header magic
	 *	- Header version
	 *	- Payload checksum
	 */
	if (header->magic != BOOT_API_IMAGE_HEADER_MAGIC_NB) {
		ERROR("Header magic\n");
		return -EINVAL;
	}

	if (header->header_version != BOOT_API_HEADER_VERSION) {
		ERROR("Header version\n");
		return -EINVAL;
	}

	for (i = 0; i < header->image_length; i++) {
		img_checksum += *(uint8_t *)(buffer + i);
	}

	if (header->payload_checksum != img_checksum) {
		ERROR("Checksum: 0x%x (awaited: 0x%x)\n", img_checksum,
		      header->payload_checksum);
		return -EINVAL;
	}

	return 0;
}

/* Read data from a partition */
static int stm32image_partition_read(io_entity_t *entity, uintptr_t buffer,
				     size_t length, size_t *length_read)
{
	int result = 0, offset, local_length = 0;
	uint8_t *local_buffer = (uint8_t *)buffer;
	boot_api_image_header_t *header =
		(boot_api_image_header_t *)first_lba_buffer;
	uintptr_t backend_handle;

	assert(entity != NULL);
	assert(buffer != 0U);
	assert(length_read != NULL);

	*length_read = 0U;

	while (*length_read == 0U) {
		if (header->magic != BOOT_API_IMAGE_HEADER_MAGIC_NB) {
			/* Check for backup as image is corrupted */
			*stm32_img += current_part->bkp_offset;
			if (*stm32_img >= stm32image_dev.device_size) {
				/* End of device reached */
				result = -ENOMEM;
				break;
			}

			local_buffer = (uint8_t *)buffer;

			result = stm32image_partition_size(entity, &length);
			if (result != 0) {
				break;
			}
		}

		/* Part of image already loaded with the header */
		memcpy(local_buffer, (uint8_t *)first_lba_buffer +
		       sizeof(boot_api_image_header_t),
		       MAX_LBA_SIZE - sizeof(boot_api_image_header_t));
		local_buffer += MAX_LBA_SIZE - sizeof(boot_api_image_header_t);
		offset = MAX_LBA_SIZE;

		/* New image length to be read */
		local_length = round_up(length -
					((MAX_LBA_SIZE) -
					 sizeof(boot_api_image_header_t)),
					stm32image_dev.lba_size);

		if ((header->load_address != 0U) &&
		    (header->load_address != buffer)) {
			ERROR("Wrong load address\n");
			panic();
		}

		result = io_open(backend_dev_handle, backend_image_spec,
				 &backend_handle);

		if (result != 0) {
			ERROR("%s: io_open (%i)\n", __func__, result);
			break;
		}

		result = io_seek(backend_handle, IO_SEEK_SET,
				 *stm32_img + offset);

		if (result != 0) {
			ERROR("%s: io_seek (%i)\n", __func__, result);
			*length_read = 0;
			io_close(backend_handle);
			break;
		}

		result = io_read(backend_handle, (uintptr_t)local_buffer,
				 local_length, length_read);

		/* Adding part of size already read from header */
		*length_read += MAX_LBA_SIZE - sizeof(boot_api_image_header_t);

		if (result != 0) {
			ERROR("%s: io_read (%i)\n", __func__, result);
			*length_read = 0;
			io_close(backend_handle);
			break;
		}

		result = check_header(header, buffer);
		if (result != 0) {
			ERROR("Header check failed\n");
			*length_read = 0;
			header->magic = 0;
			io_close(backend_handle);
			break;
		}

		io_close(backend_handle);
	}

	return result;
}

/* Close a partition */
static int stm32image_partition_close(io_entity_t *entity)
{
	current_part = NULL;

	return 0;
}

/* Register the stm32image driver with the IO abstraction */
int register_io_dev_stm32image(const io_dev_connector_t **dev_con)
{
	int result;

	assert(dev_con != NULL);

	result = io_register_device(&stm32image_dev_info);
	if (result == 0) {
		*dev_con = &stm32image_dev_connector;
	}

	return result;
}