1 // SPDX-License-Identifier: BSD-3-Clause 2 /* 3 * Copyright (c) 2015-2019, Arm Limited and Contributors. All rights reserved. 4 * Copyright (c) 2019, Linaro Limited 5 */ 6 #include <assert.h> 7 #include <confine_array_index.h> 8 #include <drivers/scmi-msg.h> 9 #include <drivers/scmi.h> 10 #include <string.h> 11 #include <trace.h> 12 #include <util.h> 13 14 #include "common.h" 15 16 static bool message_id_is_supported(unsigned int message_id); 17 18 static void report_version(struct scmi_msg *msg) 19 { 20 struct scmi_protocol_version_p2a return_values = { 21 .status = SCMI_SUCCESS, 22 .version = SCMI_PROTOCOL_VERSION_BASE, 23 }; 24 25 if (msg->in_size) { 26 scmi_status_response(msg, SCMI_PROTOCOL_ERROR); 27 return; 28 } 29 30 scmi_write_response(msg, &return_values, sizeof(return_values)); 31 } 32 33 static void report_attributes(struct scmi_msg *msg) 34 { 35 size_t protocol_count = plat_scmi_protocol_count(); 36 struct scmi_protocol_attributes_p2a return_values = { 37 .status = SCMI_SUCCESS, 38 /* Null agent count since agent discovery is not supported */ 39 .attributes = SCMI_BASE_PROTOCOL_ATTRIBUTES(protocol_count, 0), 40 }; 41 42 if (msg->in_size) { 43 scmi_status_response(msg, SCMI_PROTOCOL_ERROR); 44 return; 45 } 46 47 scmi_write_response(msg, &return_values, sizeof(return_values)); 48 } 49 50 static void report_message_attributes(struct scmi_msg *msg) 51 { 52 struct scmi_protocol_message_attributes_a2p *in_args = (void *)msg->in; 53 struct scmi_protocol_message_attributes_p2a return_values = { 54 .status = SCMI_SUCCESS, 55 /* For this protocol, attributes shall be zero */ 56 .attributes = 0, 57 }; 58 59 if (msg->in_size != sizeof(*in_args)) { 60 scmi_status_response(msg, SCMI_PROTOCOL_ERROR); 61 return; 62 } 63 64 if (!message_id_is_supported(in_args->message_id)) { 65 scmi_status_response(msg, SCMI_NOT_FOUND); 66 return; 67 } 68 69 scmi_write_response(msg, &return_values, sizeof(return_values)); 70 } 71 72 static void discover_vendor(struct scmi_msg *msg) 73 { 74 const char *name = plat_scmi_vendor_name(); 75 struct scmi_base_discover_vendor_p2a return_values = { 76 .status = SCMI_SUCCESS, 77 }; 78 79 if (msg->in_size) { 80 scmi_status_response(msg, SCMI_PROTOCOL_ERROR); 81 return; 82 } 83 84 COPY_NAME_IDENTIFIER(return_values.vendor_identifier, name); 85 86 scmi_write_response(msg, &return_values, sizeof(return_values)); 87 } 88 89 static void discover_sub_vendor(struct scmi_msg *msg) 90 { 91 const char *name = plat_scmi_sub_vendor_name(); 92 struct scmi_base_discover_sub_vendor_p2a return_values = { 93 .status = SCMI_SUCCESS, 94 }; 95 96 if (msg->in_size) { 97 scmi_status_response(msg, SCMI_PROTOCOL_ERROR); 98 return; 99 } 100 101 COPY_NAME_IDENTIFIER(return_values.sub_vendor_identifier, name); 102 103 scmi_write_response(msg, &return_values, sizeof(return_values)); 104 } 105 106 static void discover_implementation_version(struct scmi_msg *msg) 107 { 108 struct scmi_protocol_version_p2a return_values = { 109 .status = SCMI_SUCCESS, 110 .version = SCMI_IMPL_VERSION, 111 }; 112 113 if (msg->in_size) { 114 scmi_status_response(msg, SCMI_PROTOCOL_ERROR); 115 return; 116 } 117 118 scmi_write_response(msg, &return_values, sizeof(return_values)); 119 } 120 121 static unsigned int count_protocols_in_list(const uint8_t *protocol_list) 122 { 123 unsigned int count = 0; 124 125 if (protocol_list) 126 while (protocol_list[count]) 127 count++; 128 129 return count; 130 } 131 132 #define MAX_PROTOCOL_IN_LIST 8u 133 134 static void discover_list_protocols(struct scmi_msg *msg) 135 { 136 const struct scmi_base_discover_list_protocols_a2p *a2p = NULL; 137 struct scmi_base_discover_list_protocols_p2a p2a = { 138 .status = SCMI_SUCCESS, 139 }; 140 uint8_t outargs[sizeof(p2a) + MAX_PROTOCOL_IN_LIST] = { }; 141 const uint8_t *list = NULL; 142 unsigned int count = 0; 143 144 if (msg->in_size != sizeof(*a2p)) { 145 scmi_status_response(msg, SCMI_PROTOCOL_ERROR); 146 return; 147 } 148 149 assert(msg->out_size > sizeof(outargs)); 150 151 a2p = (void *)msg->in; 152 153 list = plat_scmi_protocol_list(msg->agent_id); 154 count = count_protocols_in_list(list); 155 if (count > a2p->skip) 156 count = MIN(count - a2p->skip, MAX_PROTOCOL_IN_LIST); 157 else 158 count = 0; 159 160 p2a.num_protocols = count; 161 162 memcpy(outargs, &p2a, sizeof(p2a)); 163 memcpy(outargs + sizeof(p2a), list + a2p->skip, count); 164 165 scmi_write_response(msg, outargs, sizeof(outargs)); 166 } 167 168 static const scmi_msg_handler_t scmi_base_handler_table[] = { 169 [SCMI_PROTOCOL_VERSION] = report_version, 170 [SCMI_PROTOCOL_ATTRIBUTES] = report_attributes, 171 [SCMI_PROTOCOL_MESSAGE_ATTRIBUTES] = report_message_attributes, 172 [SCMI_BASE_DISCOVER_VENDOR] = discover_vendor, 173 [SCMI_BASE_DISCOVER_SUB_VENDOR] = discover_sub_vendor, 174 [SCMI_BASE_DISCOVER_IMPLEMENTATION_VERSION] = 175 discover_implementation_version, 176 [SCMI_BASE_DISCOVER_LIST_PROTOCOLS] = discover_list_protocols, 177 }; 178 179 static bool message_id_is_supported(unsigned int message_id) 180 { 181 return message_id < ARRAY_SIZE(scmi_base_handler_table) && 182 scmi_base_handler_table[message_id]; 183 } 184 185 scmi_msg_handler_t scmi_msg_get_base_handler(struct scmi_msg *msg) 186 { 187 const size_t array_size = ARRAY_SIZE(scmi_base_handler_table); 188 unsigned int message_id = 0; 189 190 if (msg->message_id >= array_size) { 191 DMSG("Base handle not found %u", msg->message_id); 192 return NULL; 193 } 194 195 message_id = confine_array_index(msg->message_id, array_size); 196 197 return scmi_base_handler_table[message_id]; 198 } 199