1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * AMD HSMP Platform Driver 4 * Copyright (c) 2022, AMD. 5 * All Rights Reserved. 6 * 7 * This file provides a device implementation for HSMP interface 8 */ 9 10 #include <asm/amd/hsmp.h> 11 12 #include <linux/acpi.h> 13 #include <linux/delay.h> 14 #include <linux/device.h> 15 #include <linux/semaphore.h> 16 #include <linux/sysfs.h> 17 18 #include "hsmp.h" 19 20 /* HSMP Status / Error codes */ 21 #define HSMP_STATUS_NOT_READY 0x00 22 #define HSMP_STATUS_OK 0x01 23 #define HSMP_ERR_INVALID_MSG 0xFE 24 #define HSMP_ERR_INVALID_INPUT 0xFF 25 #define HSMP_ERR_PREREQ_NOT_SATISFIED 0xFD 26 #define HSMP_ERR_SMU_BUSY 0xFC 27 28 /* Timeout in millsec */ 29 #define HSMP_MSG_TIMEOUT 100 30 #define HSMP_SHORT_SLEEP 1 31 32 #define HSMP_WR true 33 #define HSMP_RD false 34 35 /* 36 * When same message numbers are used for both GET and SET operation, 37 * bit:31 indicates whether its SET or GET operation. 38 */ 39 #define CHECK_GET_BIT BIT(31) 40 41 static struct hsmp_plat_device hsmp_pdev; 42 43 /* 44 * Send a message to the HSMP port via PCI-e config space registers 45 * or by writing to MMIO space. 46 * 47 * The caller is expected to zero out any unused arguments. 48 * If a response is expected, the number of response words should be greater than 0. 49 * 50 * Returns 0 for success and populates the requested number of arguments. 51 * Returns a negative error code for failure. 52 */ 53 static int __hsmp_send_message(struct hsmp_socket *sock, struct hsmp_message *msg) 54 { 55 struct hsmp_mbaddr_info *mbinfo; 56 unsigned long timeout, short_sleep; 57 u32 mbox_status; 58 u32 index; 59 int ret; 60 61 mbinfo = &sock->mbinfo; 62 63 /* Clear the status register */ 64 mbox_status = HSMP_STATUS_NOT_READY; 65 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_WR); 66 if (ret) { 67 dev_err(sock->dev, "Error %d clearing mailbox status register\n", ret); 68 return ret; 69 } 70 71 index = 0; 72 /* Write any message arguments */ 73 while (index < msg->num_args) { 74 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2), 75 &msg->args[index], HSMP_WR); 76 if (ret) { 77 dev_err(sock->dev, "Error %d writing message argument %d\n", ret, index); 78 return ret; 79 } 80 index++; 81 } 82 83 /* Write the message ID which starts the operation */ 84 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_id_off, &msg->msg_id, HSMP_WR); 85 if (ret) { 86 dev_err(sock->dev, "Error %d writing message ID %u\n", ret, msg->msg_id); 87 return ret; 88 } 89 90 /* 91 * Depending on when the trigger write completes relative to the SMU 92 * firmware 1 ms cycle, the operation may take from tens of us to 1 ms 93 * to complete. Some operations may take more. Therefore we will try 94 * a few short duration sleeps and switch to long sleeps if we don't 95 * succeed quickly. 96 */ 97 short_sleep = jiffies + msecs_to_jiffies(HSMP_SHORT_SLEEP); 98 timeout = jiffies + msecs_to_jiffies(HSMP_MSG_TIMEOUT); 99 100 while (true) { 101 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_RD); 102 if (ret) { 103 dev_err(sock->dev, "Error %d reading mailbox status\n", ret); 104 return ret; 105 } 106 107 if (mbox_status != HSMP_STATUS_NOT_READY) 108 break; 109 110 if (!time_before(jiffies, timeout)) 111 break; 112 113 if (time_before(jiffies, short_sleep)) 114 usleep_range(50, 100); 115 else 116 usleep_range(1000, 2000); 117 } 118 119 if (unlikely(mbox_status == HSMP_STATUS_NOT_READY)) { 120 dev_err(sock->dev, "Message ID 0x%X failure : SMU tmeout (status = 0x%X)\n", 121 msg->msg_id, mbox_status); 122 return -ETIMEDOUT; 123 } else if (unlikely(mbox_status == HSMP_ERR_INVALID_MSG)) { 124 dev_err(sock->dev, "Message ID 0x%X failure : Invalid message (status = 0x%X)\n", 125 msg->msg_id, mbox_status); 126 return -ENOMSG; 127 } else if (unlikely(mbox_status == HSMP_ERR_INVALID_INPUT)) { 128 dev_err(sock->dev, "Message ID 0x%X failure : Invalid arguments (status = 0x%X)\n", 129 msg->msg_id, mbox_status); 130 return -EINVAL; 131 } else if (unlikely(mbox_status == HSMP_ERR_PREREQ_NOT_SATISFIED)) { 132 dev_err(sock->dev, "Message ID 0x%X failure : Prerequisite not satisfied (status = 0x%X)\n", 133 msg->msg_id, mbox_status); 134 return -EREMOTEIO; 135 } else if (unlikely(mbox_status == HSMP_ERR_SMU_BUSY)) { 136 dev_err(sock->dev, "Message ID 0x%X failure : SMU BUSY (status = 0x%X)\n", 137 msg->msg_id, mbox_status); 138 return -EBUSY; 139 } else if (unlikely(mbox_status != HSMP_STATUS_OK)) { 140 dev_err(sock->dev, "Message ID 0x%X unknown failure (status = 0x%X)\n", 141 msg->msg_id, mbox_status); 142 return -EIO; 143 } 144 145 /* 146 * SMU has responded OK. Read response data. 147 * SMU reads the input arguments from eight 32 bit registers starting 148 * from SMN_HSMP_MSG_DATA and writes the response data to the same 149 * SMN_HSMP_MSG_DATA address. 150 * We copy the response data if any, back to the args[]. 151 */ 152 index = 0; 153 while (index < msg->response_sz) { 154 ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2), 155 &msg->args[index], HSMP_RD); 156 if (ret) { 157 dev_err(sock->dev, "Error %d reading response %u for message ID:%u\n", 158 ret, index, msg->msg_id); 159 break; 160 } 161 index++; 162 } 163 164 return ret; 165 } 166 167 static int validate_message(struct hsmp_message *msg) 168 { 169 /* msg_id against valid range of message IDs */ 170 if (msg->msg_id < HSMP_TEST || msg->msg_id >= HSMP_MSG_ID_MAX) 171 return -ENOMSG; 172 173 /* msg_id is a reserved message ID */ 174 if (hsmp_msg_desc_table[msg->msg_id].type == HSMP_RSVD) 175 return -ENOMSG; 176 177 /* 178 * num_args passed by user should match the num_args specified in 179 * message description table. 180 */ 181 if (msg->num_args != hsmp_msg_desc_table[msg->msg_id].num_args) 182 return -EINVAL; 183 184 /* 185 * Some older HSMP SET messages are updated to add GET in the same message. 186 * In these messages, GET returns the current value and SET also returns 187 * the successfully set value. To support this GET and SET in same message 188 * while maintaining backward compatibility for the HSMP users, 189 * hsmp_msg_desc_table[] indicates only maximum allowed response_sz. 190 */ 191 if (hsmp_msg_desc_table[msg->msg_id].type == HSMP_SET_GET) { 192 if (msg->response_sz > hsmp_msg_desc_table[msg->msg_id].response_sz) 193 return -EINVAL; 194 } else { 195 /* only HSMP_SET or HSMP_GET messages go through this strict check */ 196 if (msg->response_sz != hsmp_msg_desc_table[msg->msg_id].response_sz) 197 return -EINVAL; 198 } 199 return 0; 200 } 201 202 int hsmp_send_message(struct hsmp_message *msg) 203 { 204 struct hsmp_socket *sock; 205 int ret; 206 207 if (!msg) 208 return -EINVAL; 209 ret = validate_message(msg); 210 if (ret) 211 return ret; 212 213 if (!hsmp_pdev.sock || msg->sock_ind >= hsmp_pdev.num_sockets) 214 return -ENODEV; 215 sock = &hsmp_pdev.sock[msg->sock_ind]; 216 217 ret = down_interruptible(&sock->hsmp_sem); 218 if (ret < 0) 219 return ret; 220 221 ret = __hsmp_send_message(sock, msg); 222 223 up(&sock->hsmp_sem); 224 225 return ret; 226 } 227 EXPORT_SYMBOL_NS_GPL(hsmp_send_message, "AMD_HSMP"); 228 229 int hsmp_msg_get_nargs(u16 sock_ind, u32 msg_id, u32 *data, u8 num_args) 230 { 231 struct hsmp_message msg = {}; 232 unsigned int i; 233 int ret; 234 235 if (!data) 236 return -EINVAL; 237 msg.msg_id = msg_id; 238 msg.sock_ind = sock_ind; 239 msg.response_sz = num_args; 240 241 ret = hsmp_send_message(&msg); 242 if (ret) 243 return ret; 244 245 for (i = 0; i < num_args; i++) 246 data[i] = msg.args[i]; 247 248 return 0; 249 } 250 EXPORT_SYMBOL_NS_GPL(hsmp_msg_get_nargs, "AMD_HSMP"); 251 252 int hsmp_test(u16 sock_ind, u32 value) 253 { 254 struct hsmp_message msg = { 0 }; 255 int ret; 256 257 /* 258 * Test the hsmp port by performing TEST command. The test message 259 * takes one argument and returns the value of that argument + 1. 260 */ 261 msg.msg_id = HSMP_TEST; 262 msg.num_args = 1; 263 msg.response_sz = 1; 264 msg.args[0] = value; 265 msg.sock_ind = sock_ind; 266 267 ret = hsmp_send_message(&msg); 268 if (ret) 269 return ret; 270 271 /* Check the response value */ 272 if (msg.args[0] != (value + 1)) { 273 dev_err(hsmp_pdev.sock[sock_ind].dev, 274 "Socket %d test message failed, Expected 0x%08X, received 0x%08X\n", 275 sock_ind, (value + 1), msg.args[0]); 276 return -EBADE; 277 } 278 279 return ret; 280 } 281 EXPORT_SYMBOL_NS_GPL(hsmp_test, "AMD_HSMP"); 282 283 static bool is_get_msg(struct hsmp_message *msg) 284 { 285 if (hsmp_msg_desc_table[msg->msg_id].type == HSMP_GET) 286 return true; 287 288 if (hsmp_msg_desc_table[msg->msg_id].type == HSMP_SET_GET && 289 (msg->args[0] & CHECK_GET_BIT)) 290 return true; 291 292 return false; 293 } 294 295 long hsmp_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) 296 { 297 int __user *arguser = (int __user *)arg; 298 struct hsmp_message msg = { 0 }; 299 int ret; 300 301 if (copy_struct_from_user(&msg, sizeof(msg), arguser, sizeof(struct hsmp_message))) 302 return -EFAULT; 303 304 /* 305 * Check msg_id is within the range of supported msg ids 306 * i.e within the array bounds of hsmp_msg_desc_table 307 */ 308 if (msg.msg_id < HSMP_TEST || msg.msg_id >= HSMP_MSG_ID_MAX) 309 return -ENOMSG; 310 311 switch (fp->f_mode & (FMODE_WRITE | FMODE_READ)) { 312 case FMODE_WRITE: 313 /* 314 * Device is opened in O_WRONLY mode 315 * Execute only set/configure commands 316 */ 317 if (is_get_msg(&msg)) 318 return -EPERM; 319 break; 320 case FMODE_READ: 321 /* 322 * Device is opened in O_RDONLY mode 323 * Execute only get/monitor commands 324 */ 325 if (!is_get_msg(&msg)) 326 return -EPERM; 327 break; 328 case FMODE_READ | FMODE_WRITE: 329 /* 330 * Device is opened in O_RDWR mode 331 * Execute both get/monitor and set/configure commands 332 */ 333 break; 334 default: 335 return -EPERM; 336 } 337 338 ret = hsmp_send_message(&msg); 339 if (ret) 340 return ret; 341 342 if (hsmp_msg_desc_table[msg.msg_id].response_sz > 0) { 343 /* Copy results back to user for get/monitor commands */ 344 if (copy_to_user(arguser, &msg, sizeof(struct hsmp_message))) 345 return -EFAULT; 346 } 347 348 return 0; 349 } 350 351 ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size) 352 { 353 struct hsmp_message msg = { 0 }; 354 int ret; 355 356 if (!sock || !buf) 357 return -EINVAL; 358 359 /* Do not support lseek(), also don't allow more than the size of metric table */ 360 if (size != sizeof(struct hsmp_metric_table)) { 361 dev_err(sock->dev, "Wrong buffer size\n"); 362 return -EINVAL; 363 } 364 365 msg.msg_id = HSMP_GET_METRIC_TABLE; 366 msg.sock_ind = sock->sock_ind; 367 368 ret = hsmp_send_message(&msg); 369 if (ret) 370 return ret; 371 memcpy_fromio(buf, sock->metric_tbl_addr, size); 372 373 return size; 374 } 375 EXPORT_SYMBOL_NS_GPL(hsmp_metric_tbl_read, "AMD_HSMP"); 376 377 int hsmp_get_tbl_dram_base(u16 sock_ind) 378 { 379 struct hsmp_socket *sock = &hsmp_pdev.sock[sock_ind]; 380 struct hsmp_message msg = { 0 }; 381 phys_addr_t dram_addr; 382 int ret; 383 384 msg.sock_ind = sock_ind; 385 msg.response_sz = hsmp_msg_desc_table[HSMP_GET_METRIC_TABLE_DRAM_ADDR].response_sz; 386 msg.msg_id = HSMP_GET_METRIC_TABLE_DRAM_ADDR; 387 388 ret = hsmp_send_message(&msg); 389 if (ret) 390 return ret; 391 392 /* 393 * calculate the metric table DRAM address from lower and upper 32 bits 394 * sent from SMU and ioremap it to virtual address. 395 */ 396 dram_addr = msg.args[0] | ((u64)(msg.args[1]) << 32); 397 if (!dram_addr) { 398 dev_err(sock->dev, "Invalid DRAM address for metric table\n"); 399 return -ENOMEM; 400 } 401 sock->metric_tbl_addr = devm_ioremap(sock->dev, dram_addr, 402 sizeof(struct hsmp_metric_table)); 403 if (!sock->metric_tbl_addr) { 404 dev_err(sock->dev, "Failed to ioremap metric table addr\n"); 405 return -ENOMEM; 406 } 407 return 0; 408 } 409 EXPORT_SYMBOL_NS_GPL(hsmp_get_tbl_dram_base, "AMD_HSMP"); 410 411 int hsmp_cache_proto_ver(u16 sock_ind) 412 { 413 struct hsmp_message msg = { 0 }; 414 int ret; 415 416 msg.msg_id = HSMP_GET_PROTO_VER; 417 msg.sock_ind = sock_ind; 418 msg.response_sz = hsmp_msg_desc_table[HSMP_GET_PROTO_VER].response_sz; 419 420 ret = hsmp_send_message(&msg); 421 if (!ret) 422 hsmp_pdev.proto_ver = msg.args[0]; 423 424 return ret; 425 } 426 EXPORT_SYMBOL_NS_GPL(hsmp_cache_proto_ver, "AMD_HSMP"); 427 428 static const struct file_operations hsmp_fops = { 429 .owner = THIS_MODULE, 430 .unlocked_ioctl = hsmp_ioctl, 431 .compat_ioctl = hsmp_ioctl, 432 }; 433 434 int hsmp_misc_register(struct device *dev) 435 { 436 hsmp_pdev.mdev.name = HSMP_CDEV_NAME; 437 hsmp_pdev.mdev.minor = MISC_DYNAMIC_MINOR; 438 hsmp_pdev.mdev.fops = &hsmp_fops; 439 hsmp_pdev.mdev.parent = dev; 440 hsmp_pdev.mdev.nodename = HSMP_DEVNODE_NAME; 441 hsmp_pdev.mdev.mode = 0644; 442 443 return misc_register(&hsmp_pdev.mdev); 444 } 445 EXPORT_SYMBOL_NS_GPL(hsmp_misc_register, "AMD_HSMP"); 446 447 void hsmp_misc_deregister(void) 448 { 449 misc_deregister(&hsmp_pdev.mdev); 450 } 451 EXPORT_SYMBOL_NS_GPL(hsmp_misc_deregister, "AMD_HSMP"); 452 453 struct hsmp_plat_device *get_hsmp_pdev(void) 454 { 455 return &hsmp_pdev; 456 } 457 EXPORT_SYMBOL_NS_GPL(get_hsmp_pdev, "AMD_HSMP"); 458 459 MODULE_DESCRIPTION("AMD HSMP Common driver"); 460 MODULE_VERSION(DRIVER_VERSION); 461 MODULE_LICENSE("GPL"); 462