1 /* 2 * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <assert.h> 8 9 #include <libfdt.h> 10 11 #include <common/fdt_wrappers.h> 12 #include <plat/arm/common/arm_dyn_cfg_helpers.h> 13 #include <plat/arm/common/plat_arm.h> 14 15 #define DTB_PROP_MBEDTLS_HEAP_ADDR "mbedtls_heap_addr" 16 #define DTB_PROP_MBEDTLS_HEAP_SIZE "mbedtls_heap_size" 17 18 #if MEASURED_BOOT 19 #define DTB_PROP_BL2_HASH_DATA "bl2_hash_data" 20 21 static int dtb_root = -1; 22 #endif /* MEASURED_BOOT */ 23 24 /******************************************************************************* 25 * Validate the tb_fw_config is a valid DTB file and returns the node offset 26 * to "arm,tb_fw" property. 27 * Arguments: 28 * void *dtb - pointer to the TB_FW_CONFIG in memory 29 * int *node - Returns the node offset to "arm,tb_fw" property if found. 30 * 31 * Returns 0 on success and -1 on error. 32 ******************************************************************************/ 33 int arm_dyn_tb_fw_cfg_init(void *dtb, int *node) 34 { 35 assert(dtb != NULL); 36 assert(node != NULL); 37 38 /* Check if the pointer to DT is correct */ 39 if (fdt_check_header(dtb) != 0) { 40 WARN("Invalid DTB file passed as TB_FW_CONFIG\n"); 41 return -1; 42 } 43 44 /* Assert the node offset point to "arm,tb_fw" compatible property */ 45 *node = fdt_node_offset_by_compatible(dtb, -1, "arm,tb_fw"); 46 if (*node < 0) { 47 WARN("The compatible property `arm,tb_fw` not found in the config\n"); 48 return -1; 49 } 50 51 VERBOSE("Dyn cfg: Found \"arm,tb_fw\" in the config\n"); 52 return 0; 53 } 54 55 /* 56 * This function writes the Mbed TLS heap address and size in the DTB. When it 57 * is called, it is guaranteed that a DTB is available. However it is not 58 * guaranteed that the shared Mbed TLS heap implementation is used. Thus we 59 * return error code from here and it's the responsibility of the caller to 60 * determine the action upon error. 61 * 62 * This function is supposed to be called only by BL1. 63 * 64 * Returns: 65 * 0 = success 66 * -1 = error 67 */ 68 int arm_set_dtb_mbedtls_heap_info(void *dtb, void *heap_addr, size_t heap_size) 69 { 70 #if !MEASURED_BOOT 71 int dtb_root; 72 #endif 73 /* 74 * Verify that the DTB is valid, before attempting to write to it, 75 * and get the DTB root node. 76 */ 77 int err = arm_dyn_tb_fw_cfg_init(dtb, &dtb_root); 78 if (err < 0) { 79 ERROR("Invalid TB_FW_CONFIG loaded. Unable to get root node\n"); 80 return -1; 81 } 82 83 /* 84 * Write the heap address and size in the DTB. 85 * 86 * NOTE: The variables heap_addr and heap_size are corrupted 87 * by the "fdtw_write_inplace_cells" function. After the 88 * function calls they must NOT be reused. 89 */ 90 err = fdtw_write_inplace_cells(dtb, dtb_root, 91 DTB_PROP_MBEDTLS_HEAP_ADDR, 2, &heap_addr); 92 if (err < 0) { 93 ERROR("Unable to write DTB property %s\n", 94 DTB_PROP_MBEDTLS_HEAP_ADDR); 95 return -1; 96 } 97 98 err = fdtw_write_inplace_cells(dtb, dtb_root, 99 DTB_PROP_MBEDTLS_HEAP_SIZE, 1, &heap_size); 100 if (err < 0) { 101 ERROR("Unable to write DTB property %s\n", 102 DTB_PROP_MBEDTLS_HEAP_SIZE); 103 return -1; 104 } 105 106 return 0; 107 } 108 109 #if MEASURED_BOOT 110 /* 111 * This function writes the BL2 hash data in HW_FW_CONFIG DTB. 112 * When it is called, it is guaranteed that a DTB is available. 113 * 114 * This function is supposed to be called only by BL1. 115 * 116 * Returns: 117 * 0 = success 118 * < 0 = error 119 */ 120 int arm_set_bl2_hash_info(void *dtb, void *data) 121 { 122 assert(dtb_root >= 0); 123 124 /* 125 * Write the BL2 hash data in the DTB. 126 */ 127 return fdtw_write_inplace_bytes(dtb, dtb_root, DTB_PROP_BL2_HASH_DATA, 128 TCG_DIGEST_SIZE, data); 129 } 130 #endif /* MEASURED_BOOT */ 131