1 /*
2 * Copyright (c) 2021, Arm Limited. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #include <assert.h>
8
9 #include <common/debug.h>
10 #include <common/tf_crc32.h>
11 #include <common/tbbr/tbbr_img_def.h>
12 #include <drivers/fwu/fwu.h>
13 #include <drivers/fwu/fwu_metadata.h>
14 #include <drivers/io/io_storage.h>
15
16 #include <plat/common/platform.h>
17
18 /*
19 * Assert that crc_32 is the first member of fwu_metadata structure.
20 * It avoids accessing data outside of the metadata structure during
21 * CRC32 computation if the crc_32 field gets moved due the structure
22 * member(s) addition in the future.
23 */
24 CASSERT((offsetof(struct fwu_metadata, crc_32) == 0),
25 crc_32_must_be_first_member_of_structure);
26
27 static struct fwu_metadata metadata;
28 static bool is_fwu_initialized;
29
30 /*******************************************************************************
31 * Compute CRC32 of the FWU metadata, and check it against the CRC32 value
32 * present in the FWU metadata.
33 *
34 * return -1 on error, otherwise 0
35 ******************************************************************************/
fwu_metadata_crc_check(void)36 static int fwu_metadata_crc_check(void)
37 {
38 unsigned char *data = (unsigned char *)&metadata;
39
40 uint32_t calc_crc = tf_crc32(0U, data + sizeof(metadata.crc_32),
41 (sizeof(metadata) -
42 sizeof(metadata.crc_32)));
43
44 if (metadata.crc_32 != calc_crc) {
45 return -1;
46 }
47
48 return 0;
49 }
50
51 /*******************************************************************************
52 * Check the sanity of FWU metadata.
53 *
54 * return -1 on error, otherwise 0
55 ******************************************************************************/
fwu_metadata_sanity_check(void)56 static int fwu_metadata_sanity_check(void)
57 {
58 /* ToDo: add more conditions for sanity check */
59 if ((metadata.active_index >= NR_OF_FW_BANKS) ||
60 (metadata.previous_active_index >= NR_OF_FW_BANKS)) {
61 return -1;
62 }
63
64 return 0;
65 }
66
67 /*******************************************************************************
68 * Verify and load specified FWU metadata image to local FWU metadata structure.
69 *
70 * @image_id: FWU metadata image id (either FWU_METADATA_IMAGE_ID or
71 * BKUP_FWU_METADATA_IMAGE_ID)
72 *
73 * return a negative value on error, otherwise 0
74 ******************************************************************************/
fwu_metadata_load(unsigned int image_id)75 static int fwu_metadata_load(unsigned int image_id)
76 {
77 int result;
78 uintptr_t dev_handle, image_handle, image_spec;
79 size_t bytes_read;
80
81 assert((image_id == FWU_METADATA_IMAGE_ID) ||
82 (image_id == BKUP_FWU_METADATA_IMAGE_ID));
83
84 result = plat_fwu_set_metadata_image_source(image_id,
85 &dev_handle,
86 &image_spec);
87 if (result != 0) {
88 WARN("Failed to set reference to image id=%u (%i)\n",
89 image_id, result);
90 return result;
91 }
92
93 result = io_open(dev_handle, image_spec, &image_handle);
94 if (result != 0) {
95 WARN("Failed to load image id id=%u (%i)\n",
96 image_id, result);
97 return result;
98 }
99
100 result = io_read(image_handle, (uintptr_t)&metadata,
101 sizeof(struct fwu_metadata), &bytes_read);
102
103 if (result != 0) {
104 WARN("Failed to read image id=%u (%i)\n", image_id, result);
105 goto exit;
106 }
107
108 if (sizeof(struct fwu_metadata) != bytes_read) {
109 /* return -1 in case of partial/no read */
110 result = -1;
111 WARN("Read bytes (%zu) instead of expected (%zu) bytes\n",
112 bytes_read, sizeof(struct fwu_metadata));
113 goto exit;
114 }
115
116 /* sanity check on loaded parameters */
117 result = fwu_metadata_sanity_check();
118 if (result != 0) {
119 WARN("Sanity %s\n", "check failed on FWU metadata");
120 goto exit;
121 }
122
123 /* CRC check on loaded parameters */
124 result = fwu_metadata_crc_check();
125 if (result != 0) {
126 WARN("CRC %s\n", "check failed on FWU metadata");
127 }
128
129 exit:
130 (void)io_close(image_handle);
131
132 return result;
133 }
134
135 /*******************************************************************************
136 * The system runs in the trial run state if any of the images in the active
137 * firmware bank has not been accepted yet.
138 *
139 * Returns true if the system is running in the trial state.
140 ******************************************************************************/
fwu_is_trial_run_state(void)141 bool fwu_is_trial_run_state(void)
142 {
143 bool trial_run = false;
144
145 assert(is_fwu_initialized == true);
146
147 for (unsigned int i = 0U; i < NR_OF_IMAGES_IN_FW_BANK; i++) {
148 struct fwu_image_entry *entry = &metadata.img_entry[i];
149 struct fwu_image_properties *img_props =
150 &entry->img_props[metadata.active_index];
151 if (img_props->accepted == 0) {
152 trial_run = true;
153 break;
154 }
155 }
156
157 return trial_run;
158 }
159
160 /*******************************************************************************
161 * Load verified copy of FWU metadata image kept in the platform NV storage
162 * into local FWU metadata structure.
163 * Also, update platform I/O policies with the offset address and length of
164 * firmware-updated images kept in the platform NV storage.
165 ******************************************************************************/
fwu_init(void)166 void fwu_init(void)
167 {
168 /* Load FWU metadata which will be used to load the images in the
169 * active bank as per PSA FWU specification
170 */
171 int result = fwu_metadata_load(FWU_METADATA_IMAGE_ID);
172
173 if (result != 0) {
174 WARN("loading of FWU-Metadata failed, "
175 "using Bkup-FWU-Metadata\n");
176
177 result = fwu_metadata_load(BKUP_FWU_METADATA_IMAGE_ID);
178 if (result != 0) {
179 ERROR("loading of Bkup-FWU-Metadata failed\n");
180 panic();
181 }
182 }
183
184 plat_fwu_set_images_source(&metadata);
185
186 is_fwu_initialized = true;
187 }
188