xref: /rk3399_ARM-atf/plat/arm/common/arm_dyn_cfg_helpers.c (revision ca9ffc799c6dc1d1a69c94b2640ae9897977ad91)
1 /*
2  * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <arm_dyn_cfg_helpers.h>
8 #include <assert.h>
9 #include <desc_image_load.h>
10 #include <fdt_wrappers.h>
11 #include <libfdt.h>
12 #include <plat_arm.h>
13 
14 #define DTB_PROP_MBEDTLS_HEAP_ADDR "mbedtls_heap_addr"
15 #define DTB_PROP_MBEDTLS_HEAP_SIZE "mbedtls_heap_size"
16 
17 typedef struct config_load_info_prop {
18 	unsigned int config_id;
19 	const char *config_addr;
20 	const char *config_max_size;
21 } config_load_info_prop_t;
22 
23 static const config_load_info_prop_t prop_names[] = {
24 	{HW_CONFIG_ID, "hw_config_addr", "hw_config_max_size"},
25 	{SOC_FW_CONFIG_ID, "soc_fw_config_addr", "soc_fw_config_max_size"},
26 	{TOS_FW_CONFIG_ID, "tos_fw_config_addr", "tos_fw_config_max_size"},
27 	{NT_FW_CONFIG_ID, "nt_fw_config_addr", "nt_fw_config_max_size"}
28 };
29 
30 /*******************************************************************************
31  * Helper to read the load information corresponding to the `config_id` in
32  * TB_FW_CONFIG. This function expects the following properties to be defined :
33  *	<config>_addr		size : 2 cells
34  *	<config>_max_size	size : 1 cell
35  *
36  * Arguments:
37  *	void *dtb		 - pointer to the TB_FW_CONFIG in memory
38  *	int node		 - The node offset to appropriate node in the
39  *					 DTB.
40  *	unsigned int config_id	 - The configuration id
41  *	uint64_t *config_addr	 - Returns the `config` load address if read
42  *					 is successful.
43  *	uint32_t *config_size	 - Returns the `config` size if read is
44  *					 successful.
45  *
46  * Returns 0 on success and -1 on error.
47  ******************************************************************************/
48 int arm_dyn_get_config_load_info(void *dtb, int node, unsigned int config_id,
49 		uint64_t *config_addr, uint32_t *config_size)
50 {
51 	int err;
52 	unsigned int i;
53 
54 	assert(dtb != NULL);
55 	assert(config_addr != NULL);
56 	assert(config_size != NULL);
57 
58 	for (i = 0; i < ARRAY_SIZE(prop_names); i++) {
59 		if (prop_names[i].config_id == config_id)
60 			break;
61 	}
62 
63 	if (i == ARRAY_SIZE(prop_names)) {
64 		WARN("Invalid config id %d\n", config_id);
65 		return -1;
66 	}
67 
68 	/* Check if the pointer to DT is correct */
69 	assert(fdt_check_header(dtb) == 0);
70 
71 	/* Assert the node offset point to "arm,tb_fw" compatible property */
72 	assert(node == fdt_node_offset_by_compatible(dtb, -1, "arm,tb_fw"));
73 
74 	err = fdtw_read_cells(dtb, node, prop_names[i].config_addr, 2,
75 				(void *) config_addr);
76 	if (err < 0) {
77 		WARN("Read cell failed for %s\n", prop_names[i].config_addr);
78 		return -1;
79 	}
80 
81 	err = fdtw_read_cells(dtb, node, prop_names[i].config_max_size, 1,
82 				(void *) config_size);
83 	if (err < 0) {
84 		WARN("Read cell failed for %s\n", prop_names[i].config_max_size);
85 		return -1;
86 	}
87 
88 	VERBOSE("Dyn cfg: Read config_id %d load info from TB_FW_CONFIG 0x%llx 0x%x\n",
89 				config_id, (unsigned long long)*config_addr, *config_size);
90 
91 	return 0;
92 }
93 
94 /*******************************************************************************
95  * Helper to read the `disable_auth` property in config DTB. This function
96  * expects the following properties to be present in the config DTB.
97  *	name : disable_auth		size : 1 cell
98  *
99  * Arguments:
100  *	void *dtb		 - pointer to the TB_FW_CONFIG in memory
101  *	int node		 - The node offset to appropriate node in the
102  *				   DTB.
103  *	uint64_t *disable_auth	 - The value of `disable_auth` property on
104  *				   successful read. Must be 0 or 1.
105  *
106  * Returns 0 on success and -1 on error.
107  ******************************************************************************/
108 int arm_dyn_get_disable_auth(void *dtb, int node, uint32_t *disable_auth)
109 {
110 	int err;
111 
112 	assert(dtb != NULL);
113 	assert(disable_auth != NULL);
114 
115 	/* Check if the pointer to DT is correct */
116 	assert(fdt_check_header(dtb) == 0);
117 
118 	/* Assert the node offset point to "arm,tb_fw" compatible property */
119 	assert(node == fdt_node_offset_by_compatible(dtb, -1, "arm,tb_fw"));
120 
121 	/* Locate the disable_auth cell and read the value */
122 	err = fdtw_read_cells(dtb, node, "disable_auth", 1, disable_auth);
123 	if (err < 0) {
124 		WARN("Read cell failed for `disable_auth`\n");
125 		return -1;
126 	}
127 
128 	/* Check if the value is boolean */
129 	if ((*disable_auth != 0U) && (*disable_auth != 1U)) {
130 		WARN("Invalid value for `disable_auth` cell %d\n", *disable_auth);
131 		return -1;
132 	}
133 
134 	VERBOSE("Dyn cfg: `disable_auth` cell found with value = %d\n",
135 					*disable_auth);
136 	return 0;
137 }
138 
139 /*******************************************************************************
140  * Validate the tb_fw_config is a valid DTB file and returns the node offset
141  * to "arm,tb_fw" property.
142  * Arguments:
143  *	void *dtb - pointer to the TB_FW_CONFIG in memory
144  *	int *node - Returns the node offset to "arm,tb_fw" property if found.
145  *
146  * Returns 0 on success and -1 on error.
147  ******************************************************************************/
148 int arm_dyn_tb_fw_cfg_init(void *dtb, int *node)
149 {
150 	assert(dtb != NULL);
151 	assert(node != NULL);
152 
153 	/* Check if the pointer to DT is correct */
154 	if (fdt_check_header(dtb) != 0) {
155 		WARN("Invalid DTB file passed as TB_FW_CONFIG\n");
156 		return -1;
157 	}
158 
159 	/* Assert the node offset point to "arm,tb_fw" compatible property */
160 	*node = fdt_node_offset_by_compatible(dtb, -1, "arm,tb_fw");
161 	if (*node < 0) {
162 		WARN("The compatible property `arm,tb_fw` not found in the config\n");
163 		return -1;
164 	}
165 
166 	VERBOSE("Dyn cfg: Found \"arm,tb_fw\" in the config\n");
167 	return 0;
168 }
169 
170 
171 #if TRUSTED_BOARD_BOOT && LOAD_IMAGE_V2
172 /*
173  * Reads and returns the Mbed TLS shared heap information from the DTB.
174  * This function is supposed to be called *only* when a DTB is present.
175  * This function is supposed to be called only by BL2.
176  *
177  * Returns:
178  *	0 = success
179  *	-1 = error. In this case the values of heap_addr, heap_size should be
180  *	    considered as garbage by the caller.
181  */
182 int arm_get_dtb_mbedtls_heap_info(void *dtb, void **heap_addr,
183 	size_t *heap_size)
184 {
185 	int err, dtb_root;
186 
187 	/* Verify the DTB is valid and get the root node */
188 	err = arm_dyn_tb_fw_cfg_init(dtb, &dtb_root);
189 	if (err < 0) {
190 		ERROR("%s: Invalid TB_FW_CONFIG. Cannot retrieve Mbed TLS "
191 			"heap information from DTB\n", __func__);
192 		return -1;
193 	}
194 
195 	/* Retrieve the Mbed TLS heap details from the DTB */
196 	err = fdtw_read_cells(dtb, dtb_root,
197 		DTB_PROP_MBEDTLS_HEAP_ADDR, 2, heap_addr);
198 	if (err < 0) {
199 		ERROR("%s: error while reading %s from DTB\n", __func__,
200 			DTB_PROP_MBEDTLS_HEAP_ADDR);
201 		return -1;
202 	}
203 	err = fdtw_read_cells(dtb, dtb_root,
204 		DTB_PROP_MBEDTLS_HEAP_SIZE, 1, heap_size);
205 	if (err < 0) {
206 		ERROR("%s: error while reading %s from DTB\n", __func__,
207 			DTB_PROP_MBEDTLS_HEAP_SIZE);
208 		return -1;
209 	}
210 	return 0;
211 }
212 
213 
214 /*
215  * This function writes the Mbed TLS heap address and size in the DTB. When it
216  * is called, it is guaranteed that a DTB is available. However it is not
217  * guaranteed that the shared Mbed TLS heap implementation is used. Thus we
218  * return error code from here and it's the responsibility of the caller to
219  * determine the action upon error.
220  *
221  * This function is supposed to be called only by BL1.
222  *
223  * Returns:
224  *	0 = success
225  *	1 = error
226  */
227 int arm_set_dtb_mbedtls_heap_info(void *dtb, void *heap_addr, size_t heap_size)
228 {
229 	int err, dtb_root;
230 
231 	/*
232 	 * Verify that the DTB is valid, before attempting to write to it,
233 	 * and get the DTB root node.
234 	 */
235 	err = arm_dyn_tb_fw_cfg_init(dtb, &dtb_root);
236 	if (err < 0) {
237 		ERROR("%s: Invalid TB_FW_CONFIG loaded. Unable to get "
238 			"root node\n", __func__);
239 		return -1;
240 	}
241 
242 	/*
243 	 * Write the heap address and size in the DTB.
244 	 *
245 	 * NOTE: The variables heap_addr and heap_size are corrupted
246 	 * by the "fdtw_write_inplace_cells" function. After the
247 	 * function calls they must NOT be reused.
248 	 */
249 	err = fdtw_write_inplace_cells(dtb, dtb_root,
250 		DTB_PROP_MBEDTLS_HEAP_ADDR, 2, &heap_addr);
251 	if (err < 0) {
252 		ERROR("%s: unable to write DTB property %s\n",
253 			__func__, DTB_PROP_MBEDTLS_HEAP_ADDR);
254 		return -1;
255 	}
256 
257 	err = fdtw_write_inplace_cells(dtb, dtb_root,
258 		DTB_PROP_MBEDTLS_HEAP_SIZE, 1, &heap_size);
259 	if (err < 0) {
260 		ERROR("%s: unable to write DTB property %s\n",
261 			__func__, DTB_PROP_MBEDTLS_HEAP_SIZE);
262 		return -1;
263 	}
264 
265 	return 0;
266 }
267 #endif /* TRUSTED_BOARD_BOOT && LOAD_IMAGE_V2 */
268