1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Thunderbolt/USB4 retimer support. 4 * 5 * Copyright (C) 2020, Intel Corporation 6 * Authors: Kranthi Kuntala <kranthi.kuntala@intel.com> 7 * Mika Westerberg <mika.westerberg@linux.intel.com> 8 */ 9 10 #include <linux/delay.h> 11 #include <linux/pm_runtime.h> 12 #include <linux/sched/signal.h> 13 14 #include "sb_regs.h" 15 #include "tb.h" 16 17 #define TB_MAX_RETIMER_INDEX 6 18 19 static int tb_retimer_nvm_read(void *priv, unsigned int offset, void *val, 20 size_t bytes) 21 { 22 struct tb_nvm *nvm = priv; 23 struct tb_retimer *rt = tb_to_retimer(nvm->dev); 24 int ret; 25 26 pm_runtime_get_sync(&rt->dev); 27 28 if (!mutex_trylock(&rt->tb->lock)) { 29 ret = restart_syscall(); 30 goto out; 31 } 32 33 ret = usb4_port_retimer_nvm_read(rt->port, rt->index, offset, val, bytes); 34 mutex_unlock(&rt->tb->lock); 35 36 out: 37 pm_runtime_mark_last_busy(&rt->dev); 38 pm_runtime_put_autosuspend(&rt->dev); 39 40 return ret; 41 } 42 43 static int tb_retimer_nvm_write(void *priv, unsigned int offset, void *val, 44 size_t bytes) 45 { 46 struct tb_nvm *nvm = priv; 47 struct tb_retimer *rt = tb_to_retimer(nvm->dev); 48 int ret = 0; 49 50 if (!mutex_trylock(&rt->tb->lock)) 51 return restart_syscall(); 52 53 ret = tb_nvm_write_buf(nvm, offset, val, bytes); 54 mutex_unlock(&rt->tb->lock); 55 56 return ret; 57 } 58 59 static int tb_retimer_nvm_add(struct tb_retimer *rt) 60 { 61 struct tb_nvm *nvm; 62 u32 val, nvm_size; 63 int ret; 64 65 nvm = tb_nvm_alloc(&rt->dev); 66 if (IS_ERR(nvm)) 67 return PTR_ERR(nvm); 68 69 ret = usb4_port_retimer_nvm_read(rt->port, rt->index, NVM_VERSION, &val, 70 sizeof(val)); 71 if (ret) 72 goto err_nvm; 73 74 nvm->major = val >> 16; 75 nvm->minor = val >> 8; 76 77 ret = usb4_port_retimer_nvm_read(rt->port, rt->index, NVM_FLASH_SIZE, 78 &val, sizeof(val)); 79 if (ret) 80 goto err_nvm; 81 82 nvm_size = (SZ_1M << (val & 7)) / 8; 83 nvm_size = (nvm_size - SZ_16K) / 2; 84 85 ret = tb_nvm_add_active(nvm, nvm_size, tb_retimer_nvm_read); 86 if (ret) 87 goto err_nvm; 88 89 ret = tb_nvm_add_non_active(nvm, NVM_MAX_SIZE, tb_retimer_nvm_write); 90 if (ret) 91 goto err_nvm; 92 93 rt->nvm = nvm; 94 return 0; 95 96 err_nvm: 97 tb_nvm_free(nvm); 98 return ret; 99 } 100 101 static int tb_retimer_nvm_validate_and_write(struct tb_retimer *rt) 102 { 103 unsigned int image_size, hdr_size; 104 const u8 *buf = rt->nvm->buf; 105 u16 ds_size, device; 106 107 image_size = rt->nvm->buf_data_size; 108 if (image_size < NVM_MIN_SIZE || image_size > NVM_MAX_SIZE) 109 return -EINVAL; 110 111 /* 112 * FARB pointer must point inside the image and must at least 113 * contain parts of the digital section we will be reading here. 114 */ 115 hdr_size = (*(u32 *)buf) & 0xffffff; 116 if (hdr_size + NVM_DEVID + 2 >= image_size) 117 return -EINVAL; 118 119 /* Digital section start should be aligned to 4k page */ 120 if (!IS_ALIGNED(hdr_size, SZ_4K)) 121 return -EINVAL; 122 123 /* 124 * Read digital section size and check that it also fits inside 125 * the image. 126 */ 127 ds_size = *(u16 *)(buf + hdr_size); 128 if (ds_size >= image_size) 129 return -EINVAL; 130 131 /* 132 * Make sure the device ID in the image matches the retimer 133 * hardware. 134 */ 135 device = *(u16 *)(buf + hdr_size + NVM_DEVID); 136 if (device != rt->device) 137 return -EINVAL; 138 139 /* Skip headers in the image */ 140 buf += hdr_size; 141 image_size -= hdr_size; 142 143 return usb4_port_retimer_nvm_write(rt->port, rt->index, 0, buf, 144 image_size); 145 } 146 147 static ssize_t device_show(struct device *dev, struct device_attribute *attr, 148 char *buf) 149 { 150 struct tb_retimer *rt = tb_to_retimer(dev); 151 152 return sprintf(buf, "%#x\n", rt->device); 153 } 154 static DEVICE_ATTR_RO(device); 155 156 static ssize_t nvm_authenticate_show(struct device *dev, 157 struct device_attribute *attr, char *buf) 158 { 159 struct tb_retimer *rt = tb_to_retimer(dev); 160 int ret; 161 162 if (!mutex_trylock(&rt->tb->lock)) 163 return restart_syscall(); 164 165 if (!rt->nvm) 166 ret = -EAGAIN; 167 else 168 ret = sprintf(buf, "%#x\n", rt->auth_status); 169 170 mutex_unlock(&rt->tb->lock); 171 172 return ret; 173 } 174 175 static ssize_t nvm_authenticate_store(struct device *dev, 176 struct device_attribute *attr, const char *buf, size_t count) 177 { 178 struct tb_retimer *rt = tb_to_retimer(dev); 179 bool val; 180 int ret; 181 182 pm_runtime_get_sync(&rt->dev); 183 184 if (!mutex_trylock(&rt->tb->lock)) { 185 ret = restart_syscall(); 186 goto exit_rpm; 187 } 188 189 if (!rt->nvm) { 190 ret = -EAGAIN; 191 goto exit_unlock; 192 } 193 194 ret = kstrtobool(buf, &val); 195 if (ret) 196 goto exit_unlock; 197 198 /* Always clear status */ 199 rt->auth_status = 0; 200 201 if (val) { 202 if (!rt->nvm->buf) { 203 ret = -EINVAL; 204 goto exit_unlock; 205 } 206 207 ret = tb_retimer_nvm_validate_and_write(rt); 208 if (ret) 209 goto exit_unlock; 210 211 ret = usb4_port_retimer_nvm_authenticate(rt->port, rt->index); 212 } 213 214 exit_unlock: 215 mutex_unlock(&rt->tb->lock); 216 exit_rpm: 217 pm_runtime_mark_last_busy(&rt->dev); 218 pm_runtime_put_autosuspend(&rt->dev); 219 220 if (ret) 221 return ret; 222 return count; 223 } 224 static DEVICE_ATTR_RW(nvm_authenticate); 225 226 static ssize_t nvm_version_show(struct device *dev, 227 struct device_attribute *attr, char *buf) 228 { 229 struct tb_retimer *rt = tb_to_retimer(dev); 230 int ret; 231 232 if (!mutex_trylock(&rt->tb->lock)) 233 return restart_syscall(); 234 235 if (!rt->nvm) 236 ret = -EAGAIN; 237 else 238 ret = sprintf(buf, "%x.%x\n", rt->nvm->major, rt->nvm->minor); 239 240 mutex_unlock(&rt->tb->lock); 241 return ret; 242 } 243 static DEVICE_ATTR_RO(nvm_version); 244 245 static ssize_t vendor_show(struct device *dev, struct device_attribute *attr, 246 char *buf) 247 { 248 struct tb_retimer *rt = tb_to_retimer(dev); 249 250 return sprintf(buf, "%#x\n", rt->vendor); 251 } 252 static DEVICE_ATTR_RO(vendor); 253 254 static struct attribute *retimer_attrs[] = { 255 &dev_attr_device.attr, 256 &dev_attr_nvm_authenticate.attr, 257 &dev_attr_nvm_version.attr, 258 &dev_attr_vendor.attr, 259 NULL 260 }; 261 262 static const struct attribute_group retimer_group = { 263 .attrs = retimer_attrs, 264 }; 265 266 static const struct attribute_group *retimer_groups[] = { 267 &retimer_group, 268 NULL 269 }; 270 271 static void tb_retimer_release(struct device *dev) 272 { 273 struct tb_retimer *rt = tb_to_retimer(dev); 274 275 kfree(rt); 276 } 277 278 struct device_type tb_retimer_type = { 279 .name = "thunderbolt_retimer", 280 .groups = retimer_groups, 281 .release = tb_retimer_release, 282 }; 283 284 static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status) 285 { 286 struct tb_retimer *rt; 287 u32 vendor, device; 288 int ret; 289 290 if (!port->cap_usb4) 291 return -EINVAL; 292 293 ret = usb4_port_retimer_read(port, index, USB4_SB_VENDOR_ID, &vendor, 294 sizeof(vendor)); 295 if (ret) { 296 if (ret != -ENODEV) 297 tb_port_warn(port, "failed read retimer VendorId: %d\n", ret); 298 return ret; 299 } 300 301 ret = usb4_port_retimer_read(port, index, USB4_SB_PRODUCT_ID, &device, 302 sizeof(device)); 303 if (ret) { 304 if (ret != -ENODEV) 305 tb_port_warn(port, "failed read retimer ProductId: %d\n", ret); 306 return ret; 307 } 308 309 if (vendor != PCI_VENDOR_ID_INTEL && vendor != 0x8087) { 310 tb_port_info(port, "retimer NVM format of vendor %#x is not supported\n", 311 vendor); 312 return -EOPNOTSUPP; 313 } 314 315 /* 316 * Check that it supports NVM operations. If not then don't add 317 * the device at all. 318 */ 319 ret = usb4_port_retimer_nvm_sector_size(port, index); 320 if (ret < 0) 321 return ret; 322 323 rt = kzalloc(sizeof(*rt), GFP_KERNEL); 324 if (!rt) 325 return -ENOMEM; 326 327 rt->index = index; 328 rt->vendor = vendor; 329 rt->device = device; 330 rt->auth_status = auth_status; 331 rt->port = port; 332 rt->tb = port->sw->tb; 333 334 rt->dev.parent = &port->sw->dev; 335 rt->dev.bus = &tb_bus_type; 336 rt->dev.type = &tb_retimer_type; 337 dev_set_name(&rt->dev, "%s:%u.%u", dev_name(&port->sw->dev), 338 port->port, index); 339 340 ret = device_register(&rt->dev); 341 if (ret) { 342 dev_err(&rt->dev, "failed to register retimer: %d\n", ret); 343 put_device(&rt->dev); 344 return ret; 345 } 346 347 ret = tb_retimer_nvm_add(rt); 348 if (ret) { 349 dev_err(&rt->dev, "failed to add NVM devices: %d\n", ret); 350 device_del(&rt->dev); 351 return ret; 352 } 353 354 dev_info(&rt->dev, "new retimer found, vendor=%#x device=%#x\n", 355 rt->vendor, rt->device); 356 357 pm_runtime_no_callbacks(&rt->dev); 358 pm_runtime_set_active(&rt->dev); 359 pm_runtime_enable(&rt->dev); 360 pm_runtime_set_autosuspend_delay(&rt->dev, TB_AUTOSUSPEND_DELAY); 361 pm_runtime_mark_last_busy(&rt->dev); 362 pm_runtime_use_autosuspend(&rt->dev); 363 364 return 0; 365 } 366 367 static void tb_retimer_remove(struct tb_retimer *rt) 368 { 369 dev_info(&rt->dev, "retimer disconnected\n"); 370 tb_nvm_free(rt->nvm); 371 device_unregister(&rt->dev); 372 } 373 374 struct tb_retimer_lookup { 375 const struct tb_port *port; 376 u8 index; 377 }; 378 379 static int retimer_match(struct device *dev, void *data) 380 { 381 const struct tb_retimer_lookup *lookup = data; 382 struct tb_retimer *rt = tb_to_retimer(dev); 383 384 return rt && rt->port == lookup->port && rt->index == lookup->index; 385 } 386 387 static struct tb_retimer *tb_port_find_retimer(struct tb_port *port, u8 index) 388 { 389 struct tb_retimer_lookup lookup = { .port = port, .index = index }; 390 struct device *dev; 391 392 dev = device_find_child(&port->sw->dev, &lookup, retimer_match); 393 if (dev) 394 return tb_to_retimer(dev); 395 396 return NULL; 397 } 398 399 /** 400 * tb_retimer_scan() - Scan for on-board retimers under port 401 * @port: USB4 port to scan 402 * 403 * Tries to enumerate on-board retimers connected to @port. Found 404 * retimers are registered as children of @port. Does not scan for cable 405 * retimers for now. 406 */ 407 int tb_retimer_scan(struct tb_port *port) 408 { 409 u32 status[TB_MAX_RETIMER_INDEX] = {}; 410 int ret, i, last_idx = 0; 411 412 if (!port->cap_usb4) 413 return 0; 414 415 /* 416 * Send broadcast RT to make sure retimer indices facing this 417 * port are set. 418 */ 419 ret = usb4_port_enumerate_retimers(port); 420 if (ret) 421 return ret; 422 423 /* 424 * Before doing anything else, read the authentication status. 425 * If the retimer has it set, store it for the new retimer 426 * device instance. 427 */ 428 for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) 429 usb4_port_retimer_nvm_authenticate_status(port, i, &status[i]); 430 431 for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) { 432 /* 433 * Last retimer is true only for the last on-board 434 * retimer (the one connected directly to the Type-C 435 * port). 436 */ 437 ret = usb4_port_retimer_is_last(port, i); 438 if (ret > 0) 439 last_idx = i; 440 else if (ret < 0) 441 break; 442 } 443 444 if (!last_idx) 445 return 0; 446 447 /* Add on-board retimers if they do not exist already */ 448 for (i = 1; i <= last_idx; i++) { 449 struct tb_retimer *rt; 450 451 rt = tb_port_find_retimer(port, i); 452 if (rt) { 453 put_device(&rt->dev); 454 } else { 455 ret = tb_retimer_add(port, i, status[i]); 456 if (ret && ret != -EOPNOTSUPP) 457 return ret; 458 } 459 } 460 461 return 0; 462 } 463 464 static int remove_retimer(struct device *dev, void *data) 465 { 466 struct tb_retimer *rt = tb_to_retimer(dev); 467 struct tb_port *port = data; 468 469 if (rt && rt->port == port) 470 tb_retimer_remove(rt); 471 return 0; 472 } 473 474 /** 475 * tb_retimer_remove_all() - Remove all retimers under port 476 * @port: USB4 port whose retimers to remove 477 * 478 * This removes all previously added retimers under @port. 479 */ 480 void tb_retimer_remove_all(struct tb_port *port) 481 { 482 if (port->cap_usb4) 483 device_for_each_child_reverse(&port->sw->dev, port, 484 remove_retimer); 485 } 486