1 /* 2 * Copyright © 2014 Red Hat 3 * 4 * Permission to use, copy, modify, distribute, and sell this software and its 5 * documentation for any purpose is hereby granted without fee, provided that 6 * the above copyright notice appear in all copies and that both that copyright 7 * notice and this permission notice appear in supporting documentation, and 8 * that the name of the copyright holders not be used in advertising or 9 * publicity pertaining to distribution of the software without specific, 10 * written prior permission. The copyright holders make no representations 11 * about the suitability of this software for any purpose. It is provided "as 12 * is" without express or implied warranty. 13 * 14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, 18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 20 * OF THIS SOFTWARE. 21 */ 22 23 #include <linux/kernel.h> 24 #include <linux/delay.h> 25 #include <linux/init.h> 26 #include <linux/errno.h> 27 #include <linux/sched.h> 28 #include <linux/seq_file.h> 29 #include <linux/i2c.h> 30 #include <drm/drm_dp_mst_helper.h> 31 #include <drm/drmP.h> 32 33 #include <drm/drm_fixed.h> 34 35 /** 36 * DOC: dp mst helper 37 * 38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport 39 * protocol. The helpers contain a topology manager and bandwidth manager. 40 * The helpers encapsulate the sending and received of sideband msgs. 41 */ 42 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 43 char *buf); 44 static int test_calc_pbn_mode(void); 45 46 static void drm_dp_put_port(struct drm_dp_mst_port *port); 47 48 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, 49 int id, 50 struct drm_dp_payload *payload); 51 52 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, 53 struct drm_dp_mst_port *port, 54 int offset, int size, u8 *bytes); 55 56 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 57 struct drm_dp_mst_branch *mstb); 58 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, 59 struct drm_dp_mst_branch *mstb, 60 struct drm_dp_mst_port *port); 61 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, 62 u8 *guid); 63 64 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux); 65 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux); 66 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr); 67 /* sideband msg handling */ 68 static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles) 69 { 70 u8 bitmask = 0x80; 71 u8 bitshift = 7; 72 u8 array_index = 0; 73 int number_of_bits = num_nibbles * 4; 74 u8 remainder = 0; 75 76 while (number_of_bits != 0) { 77 number_of_bits--; 78 remainder <<= 1; 79 remainder |= (data[array_index] & bitmask) >> bitshift; 80 bitmask >>= 1; 81 bitshift--; 82 if (bitmask == 0) { 83 bitmask = 0x80; 84 bitshift = 7; 85 array_index++; 86 } 87 if ((remainder & 0x10) == 0x10) 88 remainder ^= 0x13; 89 } 90 91 number_of_bits = 4; 92 while (number_of_bits != 0) { 93 number_of_bits--; 94 remainder <<= 1; 95 if ((remainder & 0x10) != 0) 96 remainder ^= 0x13; 97 } 98 99 return remainder; 100 } 101 102 static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes) 103 { 104 u8 bitmask = 0x80; 105 u8 bitshift = 7; 106 u8 array_index = 0; 107 int number_of_bits = number_of_bytes * 8; 108 u16 remainder = 0; 109 110 while (number_of_bits != 0) { 111 number_of_bits--; 112 remainder <<= 1; 113 remainder |= (data[array_index] & bitmask) >> bitshift; 114 bitmask >>= 1; 115 bitshift--; 116 if (bitmask == 0) { 117 bitmask = 0x80; 118 bitshift = 7; 119 array_index++; 120 } 121 if ((remainder & 0x100) == 0x100) 122 remainder ^= 0xd5; 123 } 124 125 number_of_bits = 8; 126 while (number_of_bits != 0) { 127 number_of_bits--; 128 remainder <<= 1; 129 if ((remainder & 0x100) != 0) 130 remainder ^= 0xd5; 131 } 132 133 return remainder & 0xff; 134 } 135 static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr) 136 { 137 u8 size = 3; 138 size += (hdr->lct / 2); 139 return size; 140 } 141 142 static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, 143 u8 *buf, int *len) 144 { 145 int idx = 0; 146 int i; 147 u8 crc4; 148 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf); 149 for (i = 0; i < (hdr->lct / 2); i++) 150 buf[idx++] = hdr->rad[i]; 151 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) | 152 (hdr->msg_len & 0x3f); 153 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4); 154 155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1); 156 buf[idx - 1] |= (crc4 & 0xf); 157 158 *len = idx; 159 } 160 161 static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, 162 u8 *buf, int buflen, u8 *hdrlen) 163 { 164 u8 crc4; 165 u8 len; 166 int i; 167 u8 idx; 168 if (buf[0] == 0) 169 return false; 170 len = 3; 171 len += ((buf[0] & 0xf0) >> 4) / 2; 172 if (len > buflen) 173 return false; 174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1); 175 176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) { 177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]); 178 return false; 179 } 180 181 hdr->lct = (buf[0] & 0xf0) >> 4; 182 hdr->lcr = (buf[0] & 0xf); 183 idx = 1; 184 for (i = 0; i < (hdr->lct / 2); i++) 185 hdr->rad[i] = buf[idx++]; 186 hdr->broadcast = (buf[idx] >> 7) & 0x1; 187 hdr->path_msg = (buf[idx] >> 6) & 0x1; 188 hdr->msg_len = buf[idx] & 0x3f; 189 idx++; 190 hdr->somt = (buf[idx] >> 7) & 0x1; 191 hdr->eomt = (buf[idx] >> 6) & 0x1; 192 hdr->seqno = (buf[idx] >> 4) & 0x1; 193 idx++; 194 *hdrlen = idx; 195 return true; 196 } 197 198 static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req, 199 struct drm_dp_sideband_msg_tx *raw) 200 { 201 int idx = 0; 202 int i; 203 u8 *buf = raw->msg; 204 buf[idx++] = req->req_type & 0x7f; 205 206 switch (req->req_type) { 207 case DP_ENUM_PATH_RESOURCES: 208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4; 209 idx++; 210 break; 211 case DP_ALLOCATE_PAYLOAD: 212 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 | 213 (req->u.allocate_payload.number_sdp_streams & 0xf); 214 idx++; 215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f); 216 idx++; 217 buf[idx] = (req->u.allocate_payload.pbn >> 8); 218 idx++; 219 buf[idx] = (req->u.allocate_payload.pbn & 0xff); 220 idx++; 221 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) { 222 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) | 223 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf); 224 idx++; 225 } 226 if (req->u.allocate_payload.number_sdp_streams & 1) { 227 i = req->u.allocate_payload.number_sdp_streams - 1; 228 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4; 229 idx++; 230 } 231 break; 232 case DP_QUERY_PAYLOAD: 233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4; 234 idx++; 235 buf[idx] = (req->u.query_payload.vcpi & 0x7f); 236 idx++; 237 break; 238 case DP_REMOTE_DPCD_READ: 239 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4; 240 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf; 241 idx++; 242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8; 243 idx++; 244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff); 245 idx++; 246 buf[idx] = (req->u.dpcd_read.num_bytes); 247 idx++; 248 break; 249 250 case DP_REMOTE_DPCD_WRITE: 251 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4; 252 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf; 253 idx++; 254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8; 255 idx++; 256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff); 257 idx++; 258 buf[idx] = (req->u.dpcd_write.num_bytes); 259 idx++; 260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes); 261 idx += req->u.dpcd_write.num_bytes; 262 break; 263 case DP_REMOTE_I2C_READ: 264 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4; 265 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3); 266 idx++; 267 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) { 268 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f; 269 idx++; 270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes; 271 idx++; 272 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes); 273 idx += req->u.i2c_read.transactions[i].num_bytes; 274 275 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5; 276 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf); 277 idx++; 278 } 279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f; 280 idx++; 281 buf[idx] = (req->u.i2c_read.num_bytes_read); 282 idx++; 283 break; 284 285 case DP_REMOTE_I2C_WRITE: 286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4; 287 idx++; 288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f; 289 idx++; 290 buf[idx] = (req->u.i2c_write.num_bytes); 291 idx++; 292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes); 293 idx += req->u.i2c_write.num_bytes; 294 break; 295 } 296 raw->cur_len = idx; 297 } 298 299 static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len) 300 { 301 u8 crc4; 302 crc4 = drm_dp_msg_data_crc4(msg, len); 303 msg[len] = crc4; 304 } 305 306 static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep, 307 struct drm_dp_sideband_msg_tx *raw) 308 { 309 int idx = 0; 310 u8 *buf = raw->msg; 311 312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f); 313 314 raw->cur_len = idx; 315 } 316 317 /* this adds a chunk of msg to the builder to get the final msg */ 318 static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg, 319 u8 *replybuf, u8 replybuflen, bool hdr) 320 { 321 int ret; 322 u8 crc4; 323 324 if (hdr) { 325 u8 hdrlen; 326 struct drm_dp_sideband_msg_hdr recv_hdr; 327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen); 328 if (ret == false) { 329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false); 330 return false; 331 } 332 333 /* get length contained in this portion */ 334 msg->curchunk_len = recv_hdr.msg_len; 335 msg->curchunk_hdrlen = hdrlen; 336 337 /* we have already gotten an somt - don't bother parsing */ 338 if (recv_hdr.somt && msg->have_somt) 339 return false; 340 341 if (recv_hdr.somt) { 342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr)); 343 msg->have_somt = true; 344 } 345 if (recv_hdr.eomt) 346 msg->have_eomt = true; 347 348 /* copy the bytes for the remainder of this header chunk */ 349 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen)); 350 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx); 351 } else { 352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen); 353 msg->curchunk_idx += replybuflen; 354 } 355 356 if (msg->curchunk_idx >= msg->curchunk_len) { 357 /* do CRC */ 358 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1); 359 /* copy chunk into bigger msg */ 360 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1); 361 msg->curlen += msg->curchunk_len - 1; 362 } 363 return true; 364 } 365 366 static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw, 367 struct drm_dp_sideband_msg_reply_body *repmsg) 368 { 369 int idx = 1; 370 int i; 371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16); 372 idx += 16; 373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf; 374 idx++; 375 if (idx > raw->curlen) 376 goto fail_len; 377 for (i = 0; i < repmsg->u.link_addr.nports; i++) { 378 if (raw->msg[idx] & 0x80) 379 repmsg->u.link_addr.ports[i].input_port = 1; 380 381 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7; 382 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf); 383 384 idx++; 385 if (idx > raw->curlen) 386 goto fail_len; 387 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1; 388 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1; 389 if (repmsg->u.link_addr.ports[i].input_port == 0) 390 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1; 391 idx++; 392 if (idx > raw->curlen) 393 goto fail_len; 394 if (repmsg->u.link_addr.ports[i].input_port == 0) { 395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]); 396 idx++; 397 if (idx > raw->curlen) 398 goto fail_len; 399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16); 400 idx += 16; 401 if (idx > raw->curlen) 402 goto fail_len; 403 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf; 404 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf); 405 idx++; 406 407 } 408 if (idx > raw->curlen) 409 goto fail_len; 410 } 411 412 return true; 413 fail_len: 414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); 415 return false; 416 } 417 418 static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw, 419 struct drm_dp_sideband_msg_reply_body *repmsg) 420 { 421 int idx = 1; 422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf; 423 idx++; 424 if (idx > raw->curlen) 425 goto fail_len; 426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx]; 427 if (idx > raw->curlen) 428 goto fail_len; 429 430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes); 431 return true; 432 fail_len: 433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); 434 return false; 435 } 436 437 static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw, 438 struct drm_dp_sideband_msg_reply_body *repmsg) 439 { 440 int idx = 1; 441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf; 442 idx++; 443 if (idx > raw->curlen) 444 goto fail_len; 445 return true; 446 fail_len: 447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen); 448 return false; 449 } 450 451 static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw, 452 struct drm_dp_sideband_msg_reply_body *repmsg) 453 { 454 int idx = 1; 455 456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf); 457 idx++; 458 if (idx > raw->curlen) 459 goto fail_len; 460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx]; 461 idx++; 462 /* TODO check */ 463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes); 464 return true; 465 fail_len: 466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen); 467 return false; 468 } 469 470 static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw, 471 struct drm_dp_sideband_msg_reply_body *repmsg) 472 { 473 int idx = 1; 474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf; 475 idx++; 476 if (idx > raw->curlen) 477 goto fail_len; 478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 479 idx += 2; 480 if (idx > raw->curlen) 481 goto fail_len; 482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 483 idx += 2; 484 if (idx > raw->curlen) 485 goto fail_len; 486 return true; 487 fail_len: 488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen); 489 return false; 490 } 491 492 static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw, 493 struct drm_dp_sideband_msg_reply_body *repmsg) 494 { 495 int idx = 1; 496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf; 497 idx++; 498 if (idx > raw->curlen) 499 goto fail_len; 500 repmsg->u.allocate_payload.vcpi = raw->msg[idx]; 501 idx++; 502 if (idx > raw->curlen) 503 goto fail_len; 504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 505 idx += 2; 506 if (idx > raw->curlen) 507 goto fail_len; 508 return true; 509 fail_len: 510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen); 511 return false; 512 } 513 514 static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw, 515 struct drm_dp_sideband_msg_reply_body *repmsg) 516 { 517 int idx = 1; 518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf; 519 idx++; 520 if (idx > raw->curlen) 521 goto fail_len; 522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); 523 idx += 2; 524 if (idx > raw->curlen) 525 goto fail_len; 526 return true; 527 fail_len: 528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen); 529 return false; 530 } 531 532 static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw, 533 struct drm_dp_sideband_msg_reply_body *msg) 534 { 535 memset(msg, 0, sizeof(*msg)); 536 msg->reply_type = (raw->msg[0] & 0x80) >> 7; 537 msg->req_type = (raw->msg[0] & 0x7f); 538 539 if (msg->reply_type) { 540 memcpy(msg->u.nak.guid, &raw->msg[1], 16); 541 msg->u.nak.reason = raw->msg[17]; 542 msg->u.nak.nak_data = raw->msg[18]; 543 return false; 544 } 545 546 switch (msg->req_type) { 547 case DP_LINK_ADDRESS: 548 return drm_dp_sideband_parse_link_address(raw, msg); 549 case DP_QUERY_PAYLOAD: 550 return drm_dp_sideband_parse_query_payload_ack(raw, msg); 551 case DP_REMOTE_DPCD_READ: 552 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg); 553 case DP_REMOTE_DPCD_WRITE: 554 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg); 555 case DP_REMOTE_I2C_READ: 556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg); 557 case DP_ENUM_PATH_RESOURCES: 558 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg); 559 case DP_ALLOCATE_PAYLOAD: 560 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg); 561 default: 562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type); 563 return false; 564 } 565 } 566 567 static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw, 568 struct drm_dp_sideband_msg_req_body *msg) 569 { 570 int idx = 1; 571 572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; 573 idx++; 574 if (idx > raw->curlen) 575 goto fail_len; 576 577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16); 578 idx += 16; 579 if (idx > raw->curlen) 580 goto fail_len; 581 582 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1; 583 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1; 584 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1; 585 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1; 586 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7); 587 idx++; 588 return true; 589 fail_len: 590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen); 591 return false; 592 } 593 594 static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw, 595 struct drm_dp_sideband_msg_req_body *msg) 596 { 597 int idx = 1; 598 599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; 600 idx++; 601 if (idx > raw->curlen) 602 goto fail_len; 603 604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16); 605 idx += 16; 606 if (idx > raw->curlen) 607 goto fail_len; 608 609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); 610 idx++; 611 return true; 612 fail_len: 613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen); 614 return false; 615 } 616 617 static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw, 618 struct drm_dp_sideband_msg_req_body *msg) 619 { 620 memset(msg, 0, sizeof(*msg)); 621 msg->req_type = (raw->msg[0] & 0x7f); 622 623 switch (msg->req_type) { 624 case DP_CONNECTION_STATUS_NOTIFY: 625 return drm_dp_sideband_parse_connection_status_notify(raw, msg); 626 case DP_RESOURCE_STATUS_NOTIFY: 627 return drm_dp_sideband_parse_resource_status_notify(raw, msg); 628 default: 629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type); 630 return false; 631 } 632 } 633 634 static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes) 635 { 636 struct drm_dp_sideband_msg_req_body req; 637 638 req.req_type = DP_REMOTE_DPCD_WRITE; 639 req.u.dpcd_write.port_number = port_num; 640 req.u.dpcd_write.dpcd_address = offset; 641 req.u.dpcd_write.num_bytes = num_bytes; 642 req.u.dpcd_write.bytes = bytes; 643 drm_dp_encode_sideband_req(&req, msg); 644 645 return 0; 646 } 647 648 static int build_link_address(struct drm_dp_sideband_msg_tx *msg) 649 { 650 struct drm_dp_sideband_msg_req_body req; 651 652 req.req_type = DP_LINK_ADDRESS; 653 drm_dp_encode_sideband_req(&req, msg); 654 return 0; 655 } 656 657 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num) 658 { 659 struct drm_dp_sideband_msg_req_body req; 660 661 req.req_type = DP_ENUM_PATH_RESOURCES; 662 req.u.port_num.port_number = port_num; 663 drm_dp_encode_sideband_req(&req, msg); 664 msg->path_msg = true; 665 return 0; 666 } 667 668 static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num, 669 u8 vcpi, uint16_t pbn) 670 { 671 struct drm_dp_sideband_msg_req_body req; 672 memset(&req, 0, sizeof(req)); 673 req.req_type = DP_ALLOCATE_PAYLOAD; 674 req.u.allocate_payload.port_number = port_num; 675 req.u.allocate_payload.vcpi = vcpi; 676 req.u.allocate_payload.pbn = pbn; 677 drm_dp_encode_sideband_req(&req, msg); 678 msg->path_msg = true; 679 return 0; 680 } 681 682 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr, 683 struct drm_dp_vcpi *vcpi) 684 { 685 int ret; 686 687 mutex_lock(&mgr->payload_lock); 688 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1); 689 if (ret > mgr->max_payloads) { 690 ret = -EINVAL; 691 DRM_DEBUG_KMS("out of payload ids %d\n", ret); 692 goto out_unlock; 693 } 694 695 set_bit(ret, &mgr->payload_mask); 696 vcpi->vcpi = ret; 697 mgr->proposed_vcpis[ret - 1] = vcpi; 698 out_unlock: 699 mutex_unlock(&mgr->payload_lock); 700 return ret; 701 } 702 703 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr, 704 int id) 705 { 706 if (id == 0) 707 return; 708 709 mutex_lock(&mgr->payload_lock); 710 DRM_DEBUG_KMS("putting payload %d\n", id); 711 clear_bit(id, &mgr->payload_mask); 712 mgr->proposed_vcpis[id - 1] = NULL; 713 mutex_unlock(&mgr->payload_lock); 714 } 715 716 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr, 717 struct drm_dp_sideband_msg_tx *txmsg) 718 { 719 bool ret; 720 mutex_lock(&mgr->qlock); 721 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX || 722 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT); 723 mutex_unlock(&mgr->qlock); 724 return ret; 725 } 726 727 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb, 728 struct drm_dp_sideband_msg_tx *txmsg) 729 { 730 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; 731 int ret; 732 733 ret = wait_event_timeout(mgr->tx_waitq, 734 check_txmsg_state(mgr, txmsg), 735 (4 * HZ)); 736 mutex_lock(&mstb->mgr->qlock); 737 if (ret > 0) { 738 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) { 739 ret = -EIO; 740 goto out; 741 } 742 } else { 743 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno); 744 745 /* dump some state */ 746 ret = -EIO; 747 748 /* remove from q */ 749 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED || 750 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) { 751 list_del(&txmsg->next); 752 } 753 754 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND || 755 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) { 756 mstb->tx_slots[txmsg->seqno] = NULL; 757 } 758 } 759 out: 760 mutex_unlock(&mgr->qlock); 761 762 return ret; 763 } 764 765 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad) 766 { 767 struct drm_dp_mst_branch *mstb; 768 769 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL); 770 if (!mstb) 771 return NULL; 772 773 mstb->lct = lct; 774 if (lct > 1) 775 memcpy(mstb->rad, rad, lct / 2); 776 INIT_LIST_HEAD(&mstb->ports); 777 kref_init(&mstb->kref); 778 return mstb; 779 } 780 781 static void drm_dp_destroy_mst_branch_device(struct kref *kref) 782 { 783 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref); 784 struct drm_dp_mst_port *port, *tmp; 785 bool wake_tx = false; 786 787 /* 788 * destroy all ports - don't need lock 789 * as there are no more references to the mst branch 790 * device at this point. 791 */ 792 list_for_each_entry_safe(port, tmp, &mstb->ports, next) { 793 list_del(&port->next); 794 drm_dp_put_port(port); 795 } 796 797 /* drop any tx slots msg */ 798 mutex_lock(&mstb->mgr->qlock); 799 if (mstb->tx_slots[0]) { 800 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 801 mstb->tx_slots[0] = NULL; 802 wake_tx = true; 803 } 804 if (mstb->tx_slots[1]) { 805 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 806 mstb->tx_slots[1] = NULL; 807 wake_tx = true; 808 } 809 mutex_unlock(&mstb->mgr->qlock); 810 811 if (wake_tx) 812 wake_up(&mstb->mgr->tx_waitq); 813 kfree(mstb); 814 } 815 816 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb) 817 { 818 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device); 819 } 820 821 822 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt) 823 { 824 struct drm_dp_mst_branch *mstb; 825 826 switch (old_pdt) { 827 case DP_PEER_DEVICE_DP_LEGACY_CONV: 828 case DP_PEER_DEVICE_SST_SINK: 829 /* remove i2c over sideband */ 830 drm_dp_mst_unregister_i2c_bus(&port->aux); 831 break; 832 case DP_PEER_DEVICE_MST_BRANCHING: 833 mstb = port->mstb; 834 port->mstb = NULL; 835 drm_dp_put_mst_branch_device(mstb); 836 break; 837 } 838 } 839 840 static void drm_dp_destroy_port(struct kref *kref) 841 { 842 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref); 843 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 844 845 if (!port->input) { 846 port->vcpi.num_slots = 0; 847 848 kfree(port->cached_edid); 849 850 /* 851 * The only time we don't have a connector 852 * on an output port is if the connector init 853 * fails. 854 */ 855 if (port->connector) { 856 /* we can't destroy the connector here, as 857 * we might be holding the mode_config.mutex 858 * from an EDID retrieval */ 859 860 mutex_lock(&mgr->destroy_connector_lock); 861 list_add(&port->next, &mgr->destroy_connector_list); 862 mutex_unlock(&mgr->destroy_connector_lock); 863 schedule_work(&mgr->destroy_connector_work); 864 return; 865 } 866 /* no need to clean up vcpi 867 * as if we have no connector we never setup a vcpi */ 868 drm_dp_port_teardown_pdt(port, port->pdt); 869 } 870 kfree(port); 871 } 872 873 static void drm_dp_put_port(struct drm_dp_mst_port *port) 874 { 875 kref_put(&port->kref, drm_dp_destroy_port); 876 } 877 878 static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find) 879 { 880 struct drm_dp_mst_port *port; 881 struct drm_dp_mst_branch *rmstb; 882 if (to_find == mstb) { 883 kref_get(&mstb->kref); 884 return mstb; 885 } 886 list_for_each_entry(port, &mstb->ports, next) { 887 if (port->mstb) { 888 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find); 889 if (rmstb) 890 return rmstb; 891 } 892 } 893 return NULL; 894 } 895 896 static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb) 897 { 898 struct drm_dp_mst_branch *rmstb = NULL; 899 mutex_lock(&mgr->lock); 900 if (mgr->mst_primary) 901 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb); 902 mutex_unlock(&mgr->lock); 903 return rmstb; 904 } 905 906 static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find) 907 { 908 struct drm_dp_mst_port *port, *mport; 909 910 list_for_each_entry(port, &mstb->ports, next) { 911 if (port == to_find) { 912 kref_get(&port->kref); 913 return port; 914 } 915 if (port->mstb) { 916 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find); 917 if (mport) 918 return mport; 919 } 920 } 921 return NULL; 922 } 923 924 static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 925 { 926 struct drm_dp_mst_port *rport = NULL; 927 mutex_lock(&mgr->lock); 928 if (mgr->mst_primary) 929 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port); 930 mutex_unlock(&mgr->lock); 931 return rport; 932 } 933 934 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num) 935 { 936 struct drm_dp_mst_port *port; 937 938 list_for_each_entry(port, &mstb->ports, next) { 939 if (port->port_num == port_num) { 940 kref_get(&port->kref); 941 return port; 942 } 943 } 944 945 return NULL; 946 } 947 948 /* 949 * calculate a new RAD for this MST branch device 950 * if parent has an LCT of 2 then it has 1 nibble of RAD, 951 * if parent has an LCT of 3 then it has 2 nibbles of RAD, 952 */ 953 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port, 954 u8 *rad) 955 { 956 int lct = port->parent->lct; 957 int shift = 4; 958 int idx = lct / 2; 959 if (lct > 1) { 960 memcpy(rad, port->parent->rad, idx); 961 shift = (lct % 2) ? 4 : 0; 962 } else 963 rad[0] = 0; 964 965 rad[idx] |= port->port_num << shift; 966 return lct + 1; 967 } 968 969 /* 970 * return sends link address for new mstb 971 */ 972 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) 973 { 974 int ret; 975 u8 rad[6], lct; 976 bool send_link = false; 977 switch (port->pdt) { 978 case DP_PEER_DEVICE_DP_LEGACY_CONV: 979 case DP_PEER_DEVICE_SST_SINK: 980 /* add i2c over sideband */ 981 ret = drm_dp_mst_register_i2c_bus(&port->aux); 982 break; 983 case DP_PEER_DEVICE_MST_BRANCHING: 984 lct = drm_dp_calculate_rad(port, rad); 985 986 port->mstb = drm_dp_add_mst_branch_device(lct, rad); 987 port->mstb->mgr = port->mgr; 988 port->mstb->port_parent = port; 989 990 send_link = true; 991 break; 992 } 993 return send_link; 994 } 995 996 static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb, 997 struct drm_dp_mst_port *port) 998 { 999 int ret; 1000 if (port->dpcd_rev >= 0x12) { 1001 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid); 1002 if (!port->guid_valid) { 1003 ret = drm_dp_send_dpcd_write(mstb->mgr, 1004 port, 1005 DP_GUID, 1006 16, port->guid); 1007 port->guid_valid = true; 1008 } 1009 } 1010 } 1011 1012 static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb, 1013 int pnum, 1014 char *proppath, 1015 size_t proppath_size) 1016 { 1017 int i; 1018 char temp[8]; 1019 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id); 1020 for (i = 0; i < (mstb->lct - 1); i++) { 1021 int shift = (i % 2) ? 0 : 4; 1022 int port_num = mstb->rad[i / 2] >> shift; 1023 snprintf(temp, sizeof(temp), "-%d", port_num); 1024 strlcat(proppath, temp, proppath_size); 1025 } 1026 snprintf(temp, sizeof(temp), "-%d", pnum); 1027 strlcat(proppath, temp, proppath_size); 1028 } 1029 1030 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb, 1031 struct device *dev, 1032 struct drm_dp_link_addr_reply_port *port_msg) 1033 { 1034 struct drm_dp_mst_port *port; 1035 bool ret; 1036 bool created = false; 1037 int old_pdt = 0; 1038 int old_ddps = 0; 1039 port = drm_dp_get_port(mstb, port_msg->port_number); 1040 if (!port) { 1041 port = kzalloc(sizeof(*port), GFP_KERNEL); 1042 if (!port) 1043 return; 1044 kref_init(&port->kref); 1045 port->parent = mstb; 1046 port->port_num = port_msg->port_number; 1047 port->mgr = mstb->mgr; 1048 port->aux.name = "DPMST"; 1049 port->aux.dev = dev; 1050 created = true; 1051 } else { 1052 old_pdt = port->pdt; 1053 old_ddps = port->ddps; 1054 } 1055 1056 port->pdt = port_msg->peer_device_type; 1057 port->input = port_msg->input_port; 1058 port->mcs = port_msg->mcs; 1059 port->ddps = port_msg->ddps; 1060 port->ldps = port_msg->legacy_device_plug_status; 1061 port->dpcd_rev = port_msg->dpcd_revision; 1062 port->num_sdp_streams = port_msg->num_sdp_streams; 1063 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks; 1064 memcpy(port->guid, port_msg->peer_guid, 16); 1065 1066 /* manage mstb port lists with mgr lock - take a reference 1067 for this list */ 1068 if (created) { 1069 mutex_lock(&mstb->mgr->lock); 1070 kref_get(&port->kref); 1071 list_add(&port->next, &mstb->ports); 1072 mutex_unlock(&mstb->mgr->lock); 1073 } 1074 1075 if (old_ddps != port->ddps) { 1076 if (port->ddps) { 1077 drm_dp_check_port_guid(mstb, port); 1078 if (!port->input) 1079 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port); 1080 } else { 1081 port->guid_valid = false; 1082 port->available_pbn = 0; 1083 } 1084 } 1085 1086 if (old_pdt != port->pdt && !port->input) { 1087 drm_dp_port_teardown_pdt(port, old_pdt); 1088 1089 ret = drm_dp_port_setup_pdt(port); 1090 if (ret == true) 1091 drm_dp_send_link_address(mstb->mgr, port->mstb); 1092 } 1093 1094 if (created && !port->input) { 1095 char proppath[255]; 1096 1097 build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath)); 1098 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath); 1099 if (!port->connector) { 1100 /* remove it from the port list */ 1101 mutex_lock(&mstb->mgr->lock); 1102 list_del(&port->next); 1103 mutex_unlock(&mstb->mgr->lock); 1104 /* drop port list reference */ 1105 drm_dp_put_port(port); 1106 goto out; 1107 } 1108 if (port->port_num >= DP_MST_LOGICAL_PORT_0) { 1109 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc); 1110 drm_mode_connector_set_tile_property(port->connector); 1111 } 1112 (*mstb->mgr->cbs->register_connector)(port->connector); 1113 } 1114 1115 out: 1116 /* put reference to this port */ 1117 drm_dp_put_port(port); 1118 } 1119 1120 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb, 1121 struct drm_dp_connection_status_notify *conn_stat) 1122 { 1123 struct drm_dp_mst_port *port; 1124 int old_pdt; 1125 int old_ddps; 1126 bool dowork = false; 1127 port = drm_dp_get_port(mstb, conn_stat->port_number); 1128 if (!port) 1129 return; 1130 1131 old_ddps = port->ddps; 1132 old_pdt = port->pdt; 1133 port->pdt = conn_stat->peer_device_type; 1134 port->mcs = conn_stat->message_capability_status; 1135 port->ldps = conn_stat->legacy_device_plug_status; 1136 port->ddps = conn_stat->displayport_device_plug_status; 1137 1138 if (old_ddps != port->ddps) { 1139 if (port->ddps) { 1140 drm_dp_check_port_guid(mstb, port); 1141 dowork = true; 1142 } else { 1143 port->guid_valid = false; 1144 port->available_pbn = 0; 1145 } 1146 } 1147 if (old_pdt != port->pdt && !port->input) { 1148 drm_dp_port_teardown_pdt(port, old_pdt); 1149 1150 if (drm_dp_port_setup_pdt(port)) 1151 dowork = true; 1152 } 1153 1154 drm_dp_put_port(port); 1155 if (dowork) 1156 queue_work(system_long_wq, &mstb->mgr->work); 1157 1158 } 1159 1160 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr, 1161 u8 lct, u8 *rad) 1162 { 1163 struct drm_dp_mst_branch *mstb; 1164 struct drm_dp_mst_port *port; 1165 int i; 1166 /* find the port by iterating down */ 1167 1168 mutex_lock(&mgr->lock); 1169 mstb = mgr->mst_primary; 1170 1171 for (i = 0; i < lct - 1; i++) { 1172 int shift = (i % 2) ? 0 : 4; 1173 int port_num = rad[i / 2] >> shift; 1174 1175 list_for_each_entry(port, &mstb->ports, next) { 1176 if (port->port_num == port_num) { 1177 mstb = port->mstb; 1178 if (!mstb) { 1179 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]); 1180 goto out; 1181 } 1182 1183 break; 1184 } 1185 } 1186 } 1187 kref_get(&mstb->kref); 1188 out: 1189 mutex_unlock(&mgr->lock); 1190 return mstb; 1191 } 1192 1193 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1194 struct drm_dp_mst_branch *mstb) 1195 { 1196 struct drm_dp_mst_port *port; 1197 struct drm_dp_mst_branch *mstb_child; 1198 if (!mstb->link_address_sent) 1199 drm_dp_send_link_address(mgr, mstb); 1200 1201 list_for_each_entry(port, &mstb->ports, next) { 1202 if (port->input) 1203 continue; 1204 1205 if (!port->ddps) 1206 continue; 1207 1208 if (!port->available_pbn) 1209 drm_dp_send_enum_path_resources(mgr, mstb, port); 1210 1211 if (port->mstb) { 1212 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb); 1213 if (mstb_child) { 1214 drm_dp_check_and_send_link_address(mgr, mstb_child); 1215 drm_dp_put_mst_branch_device(mstb_child); 1216 } 1217 } 1218 } 1219 } 1220 1221 static void drm_dp_mst_link_probe_work(struct work_struct *work) 1222 { 1223 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work); 1224 struct drm_dp_mst_branch *mstb; 1225 1226 mutex_lock(&mgr->lock); 1227 mstb = mgr->mst_primary; 1228 if (mstb) { 1229 kref_get(&mstb->kref); 1230 } 1231 mutex_unlock(&mgr->lock); 1232 if (mstb) { 1233 drm_dp_check_and_send_link_address(mgr, mstb); 1234 drm_dp_put_mst_branch_device(mstb); 1235 } 1236 } 1237 1238 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, 1239 u8 *guid) 1240 { 1241 static u8 zero_guid[16]; 1242 1243 if (!memcmp(guid, zero_guid, 16)) { 1244 u64 salt = get_jiffies_64(); 1245 memcpy(&guid[0], &salt, sizeof(u64)); 1246 memcpy(&guid[8], &salt, sizeof(u64)); 1247 return false; 1248 } 1249 return true; 1250 } 1251 1252 #if 0 1253 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes) 1254 { 1255 struct drm_dp_sideband_msg_req_body req; 1256 1257 req.req_type = DP_REMOTE_DPCD_READ; 1258 req.u.dpcd_read.port_number = port_num; 1259 req.u.dpcd_read.dpcd_address = offset; 1260 req.u.dpcd_read.num_bytes = num_bytes; 1261 drm_dp_encode_sideband_req(&req, msg); 1262 1263 return 0; 1264 } 1265 #endif 1266 1267 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr, 1268 bool up, u8 *msg, int len) 1269 { 1270 int ret; 1271 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE; 1272 int tosend, total, offset; 1273 int retries = 0; 1274 1275 retry: 1276 total = len; 1277 offset = 0; 1278 do { 1279 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total); 1280 1281 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset, 1282 &msg[offset], 1283 tosend); 1284 if (ret != tosend) { 1285 if (ret == -EIO && retries < 5) { 1286 retries++; 1287 goto retry; 1288 } 1289 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret); 1290 1291 return -EIO; 1292 } 1293 offset += tosend; 1294 total -= tosend; 1295 } while (total > 0); 1296 return 0; 1297 } 1298 1299 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr, 1300 struct drm_dp_sideband_msg_tx *txmsg) 1301 { 1302 struct drm_dp_mst_branch *mstb = txmsg->dst; 1303 1304 /* both msg slots are full */ 1305 if (txmsg->seqno == -1) { 1306 if (mstb->tx_slots[0] && mstb->tx_slots[1]) { 1307 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__); 1308 return -EAGAIN; 1309 } 1310 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) { 1311 txmsg->seqno = mstb->last_seqno; 1312 mstb->last_seqno ^= 1; 1313 } else if (mstb->tx_slots[0] == NULL) 1314 txmsg->seqno = 0; 1315 else 1316 txmsg->seqno = 1; 1317 mstb->tx_slots[txmsg->seqno] = txmsg; 1318 } 1319 hdr->broadcast = 0; 1320 hdr->path_msg = txmsg->path_msg; 1321 hdr->lct = mstb->lct; 1322 hdr->lcr = mstb->lct - 1; 1323 if (mstb->lct > 1) 1324 memcpy(hdr->rad, mstb->rad, mstb->lct / 2); 1325 hdr->seqno = txmsg->seqno; 1326 return 0; 1327 } 1328 /* 1329 * process a single block of the next message in the sideband queue 1330 */ 1331 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, 1332 struct drm_dp_sideband_msg_tx *txmsg, 1333 bool up) 1334 { 1335 u8 chunk[48]; 1336 struct drm_dp_sideband_msg_hdr hdr; 1337 int len, space, idx, tosend; 1338 int ret; 1339 1340 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr)); 1341 1342 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) { 1343 txmsg->seqno = -1; 1344 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND; 1345 } 1346 1347 /* make hdr from dst mst - for replies use seqno 1348 otherwise assign one */ 1349 ret = set_hdr_from_dst_qlock(&hdr, txmsg); 1350 if (ret < 0) 1351 return ret; 1352 1353 /* amount left to send in this message */ 1354 len = txmsg->cur_len - txmsg->cur_offset; 1355 1356 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */ 1357 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr); 1358 1359 tosend = min(len, space); 1360 if (len == txmsg->cur_len) 1361 hdr.somt = 1; 1362 if (space >= len) 1363 hdr.eomt = 1; 1364 1365 1366 hdr.msg_len = tosend + 1; 1367 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx); 1368 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend); 1369 /* add crc at end */ 1370 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend); 1371 idx += tosend + 1; 1372 1373 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx); 1374 if (ret) { 1375 DRM_DEBUG_KMS("sideband msg failed to send\n"); 1376 return ret; 1377 } 1378 1379 txmsg->cur_offset += tosend; 1380 if (txmsg->cur_offset == txmsg->cur_len) { 1381 txmsg->state = DRM_DP_SIDEBAND_TX_SENT; 1382 return 1; 1383 } 1384 return 0; 1385 } 1386 1387 /* must be called holding qlock */ 1388 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) 1389 { 1390 struct drm_dp_sideband_msg_tx *txmsg; 1391 int ret; 1392 1393 /* construct a chunk from the first msg in the tx_msg queue */ 1394 if (list_empty(&mgr->tx_msg_downq)) { 1395 mgr->tx_down_in_progress = false; 1396 return; 1397 } 1398 mgr->tx_down_in_progress = true; 1399 1400 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next); 1401 ret = process_single_tx_qlock(mgr, txmsg, false); 1402 if (ret == 1) { 1403 /* txmsg is sent it should be in the slots now */ 1404 list_del(&txmsg->next); 1405 } else if (ret) { 1406 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1407 list_del(&txmsg->next); 1408 if (txmsg->seqno != -1) 1409 txmsg->dst->tx_slots[txmsg->seqno] = NULL; 1410 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 1411 wake_up(&mgr->tx_waitq); 1412 } 1413 if (list_empty(&mgr->tx_msg_downq)) { 1414 mgr->tx_down_in_progress = false; 1415 return; 1416 } 1417 } 1418 1419 /* called holding qlock */ 1420 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) 1421 { 1422 struct drm_dp_sideband_msg_tx *txmsg; 1423 int ret; 1424 1425 /* construct a chunk from the first msg in the tx_msg queue */ 1426 if (list_empty(&mgr->tx_msg_upq)) { 1427 mgr->tx_up_in_progress = false; 1428 return; 1429 } 1430 1431 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next); 1432 ret = process_single_tx_qlock(mgr, txmsg, true); 1433 if (ret == 1) { 1434 /* up txmsgs aren't put in slots - so free after we send it */ 1435 list_del(&txmsg->next); 1436 kfree(txmsg); 1437 } else if (ret) 1438 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1439 mgr->tx_up_in_progress = true; 1440 } 1441 1442 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr, 1443 struct drm_dp_sideband_msg_tx *txmsg) 1444 { 1445 mutex_lock(&mgr->qlock); 1446 list_add_tail(&txmsg->next, &mgr->tx_msg_downq); 1447 if (!mgr->tx_down_in_progress) 1448 process_single_down_tx_qlock(mgr); 1449 mutex_unlock(&mgr->qlock); 1450 } 1451 1452 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1453 struct drm_dp_mst_branch *mstb) 1454 { 1455 int len; 1456 struct drm_dp_sideband_msg_tx *txmsg; 1457 int ret; 1458 1459 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1460 if (!txmsg) 1461 return; 1462 1463 txmsg->dst = mstb; 1464 len = build_link_address(txmsg); 1465 1466 mstb->link_address_sent = true; 1467 drm_dp_queue_down_tx(mgr, txmsg); 1468 1469 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1470 if (ret > 0) { 1471 int i; 1472 1473 if (txmsg->reply.reply_type == 1) 1474 DRM_DEBUG_KMS("link address nak received\n"); 1475 else { 1476 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports); 1477 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1478 DRM_DEBUG_KMS("port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i, 1479 txmsg->reply.u.link_addr.ports[i].input_port, 1480 txmsg->reply.u.link_addr.ports[i].peer_device_type, 1481 txmsg->reply.u.link_addr.ports[i].port_number, 1482 txmsg->reply.u.link_addr.ports[i].dpcd_revision, 1483 txmsg->reply.u.link_addr.ports[i].mcs, 1484 txmsg->reply.u.link_addr.ports[i].ddps, 1485 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status, 1486 txmsg->reply.u.link_addr.ports[i].num_sdp_streams, 1487 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks); 1488 } 1489 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1490 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]); 1491 } 1492 (*mgr->cbs->hotplug)(mgr); 1493 } 1494 } else { 1495 mstb->link_address_sent = false; 1496 DRM_DEBUG_KMS("link address failed %d\n", ret); 1497 } 1498 1499 kfree(txmsg); 1500 } 1501 1502 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, 1503 struct drm_dp_mst_branch *mstb, 1504 struct drm_dp_mst_port *port) 1505 { 1506 int len; 1507 struct drm_dp_sideband_msg_tx *txmsg; 1508 int ret; 1509 1510 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1511 if (!txmsg) 1512 return -ENOMEM; 1513 1514 txmsg->dst = mstb; 1515 len = build_enum_path_resources(txmsg, port->port_num); 1516 1517 drm_dp_queue_down_tx(mgr, txmsg); 1518 1519 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1520 if (ret > 0) { 1521 if (txmsg->reply.reply_type == 1) 1522 DRM_DEBUG_KMS("enum path resources nak received\n"); 1523 else { 1524 if (port->port_num != txmsg->reply.u.path_resources.port_number) 1525 DRM_ERROR("got incorrect port in response\n"); 1526 DRM_DEBUG_KMS("enum path resources %d: %d %d\n", txmsg->reply.u.path_resources.port_number, txmsg->reply.u.path_resources.full_payload_bw_number, 1527 txmsg->reply.u.path_resources.avail_payload_bw_number); 1528 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number; 1529 } 1530 } 1531 1532 kfree(txmsg); 1533 return 0; 1534 } 1535 1536 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr, 1537 struct drm_dp_mst_port *port, 1538 int id, 1539 int pbn) 1540 { 1541 struct drm_dp_sideband_msg_tx *txmsg; 1542 struct drm_dp_mst_branch *mstb; 1543 int len, ret; 1544 1545 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1546 if (!mstb) 1547 return -EINVAL; 1548 1549 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1550 if (!txmsg) { 1551 ret = -ENOMEM; 1552 goto fail_put; 1553 } 1554 1555 txmsg->dst = mstb; 1556 len = build_allocate_payload(txmsg, port->port_num, 1557 id, 1558 pbn); 1559 1560 drm_dp_queue_down_tx(mgr, txmsg); 1561 1562 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1563 if (ret > 0) { 1564 if (txmsg->reply.reply_type == 1) { 1565 ret = -EINVAL; 1566 } else 1567 ret = 0; 1568 } 1569 kfree(txmsg); 1570 fail_put: 1571 drm_dp_put_mst_branch_device(mstb); 1572 return ret; 1573 } 1574 1575 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1576 int id, 1577 struct drm_dp_payload *payload) 1578 { 1579 int ret; 1580 1581 ret = drm_dp_dpcd_write_payload(mgr, id, payload); 1582 if (ret < 0) { 1583 payload->payload_state = 0; 1584 return ret; 1585 } 1586 payload->payload_state = DP_PAYLOAD_LOCAL; 1587 return 0; 1588 } 1589 1590 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1591 struct drm_dp_mst_port *port, 1592 int id, 1593 struct drm_dp_payload *payload) 1594 { 1595 int ret; 1596 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn); 1597 if (ret < 0) 1598 return ret; 1599 payload->payload_state = DP_PAYLOAD_REMOTE; 1600 return ret; 1601 } 1602 1603 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1604 struct drm_dp_mst_port *port, 1605 int id, 1606 struct drm_dp_payload *payload) 1607 { 1608 DRM_DEBUG_KMS("\n"); 1609 /* its okay for these to fail */ 1610 if (port) { 1611 drm_dp_payload_send_msg(mgr, port, id, 0); 1612 } 1613 1614 drm_dp_dpcd_write_payload(mgr, id, payload); 1615 payload->payload_state = 0; 1616 return 0; 1617 } 1618 1619 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1620 int id, 1621 struct drm_dp_payload *payload) 1622 { 1623 payload->payload_state = 0; 1624 return 0; 1625 } 1626 1627 /** 1628 * drm_dp_update_payload_part1() - Execute payload update part 1 1629 * @mgr: manager to use. 1630 * 1631 * This iterates over all proposed virtual channels, and tries to 1632 * allocate space in the link for them. For 0->slots transitions, 1633 * this step just writes the VCPI to the MST device. For slots->0 1634 * transitions, this writes the updated VCPIs and removes the 1635 * remote VC payloads. 1636 * 1637 * after calling this the driver should generate ACT and payload 1638 * packets. 1639 */ 1640 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr) 1641 { 1642 int i; 1643 int cur_slots = 1; 1644 struct drm_dp_payload req_payload; 1645 struct drm_dp_mst_port *port; 1646 1647 mutex_lock(&mgr->payload_lock); 1648 for (i = 0; i < mgr->max_payloads; i++) { 1649 /* solve the current payloads - compare to the hw ones 1650 - update the hw view */ 1651 req_payload.start_slot = cur_slots; 1652 if (mgr->proposed_vcpis[i]) { 1653 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1654 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots; 1655 } else { 1656 port = NULL; 1657 req_payload.num_slots = 0; 1658 } 1659 /* work out what is required to happen with this payload */ 1660 if (mgr->payloads[i].start_slot != req_payload.start_slot || 1661 mgr->payloads[i].num_slots != req_payload.num_slots) { 1662 1663 /* need to push an update for this payload */ 1664 if (req_payload.num_slots) { 1665 drm_dp_create_payload_step1(mgr, i + 1, &req_payload); 1666 mgr->payloads[i].num_slots = req_payload.num_slots; 1667 } else if (mgr->payloads[i].num_slots) { 1668 mgr->payloads[i].num_slots = 0; 1669 drm_dp_destroy_payload_step1(mgr, port, i + 1, &mgr->payloads[i]); 1670 req_payload.payload_state = mgr->payloads[i].payload_state; 1671 } else 1672 req_payload.payload_state = 0; 1673 1674 mgr->payloads[i].start_slot = req_payload.start_slot; 1675 mgr->payloads[i].payload_state = req_payload.payload_state; 1676 } 1677 cur_slots += req_payload.num_slots; 1678 } 1679 mutex_unlock(&mgr->payload_lock); 1680 1681 return 0; 1682 } 1683 EXPORT_SYMBOL(drm_dp_update_payload_part1); 1684 1685 /** 1686 * drm_dp_update_payload_part2() - Execute payload update part 2 1687 * @mgr: manager to use. 1688 * 1689 * This iterates over all proposed virtual channels, and tries to 1690 * allocate space in the link for them. For 0->slots transitions, 1691 * this step writes the remote VC payload commands. For slots->0 1692 * this just resets some internal state. 1693 */ 1694 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr) 1695 { 1696 struct drm_dp_mst_port *port; 1697 int i; 1698 int ret; 1699 mutex_lock(&mgr->payload_lock); 1700 for (i = 0; i < mgr->max_payloads; i++) { 1701 1702 if (!mgr->proposed_vcpis[i]) 1703 continue; 1704 1705 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1706 1707 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state); 1708 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) { 1709 ret = drm_dp_create_payload_step2(mgr, port, i + 1, &mgr->payloads[i]); 1710 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { 1711 ret = drm_dp_destroy_payload_step2(mgr, i + 1, &mgr->payloads[i]); 1712 } 1713 if (ret) { 1714 mutex_unlock(&mgr->payload_lock); 1715 return ret; 1716 } 1717 } 1718 mutex_unlock(&mgr->payload_lock); 1719 return 0; 1720 } 1721 EXPORT_SYMBOL(drm_dp_update_payload_part2); 1722 1723 #if 0 /* unused as of yet */ 1724 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, 1725 struct drm_dp_mst_port *port, 1726 int offset, int size) 1727 { 1728 int len; 1729 struct drm_dp_sideband_msg_tx *txmsg; 1730 1731 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1732 if (!txmsg) 1733 return -ENOMEM; 1734 1735 len = build_dpcd_read(txmsg, port->port_num, 0, 8); 1736 txmsg->dst = port->parent; 1737 1738 drm_dp_queue_down_tx(mgr, txmsg); 1739 1740 return 0; 1741 } 1742 #endif 1743 1744 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, 1745 struct drm_dp_mst_port *port, 1746 int offset, int size, u8 *bytes) 1747 { 1748 int len; 1749 int ret; 1750 struct drm_dp_sideband_msg_tx *txmsg; 1751 struct drm_dp_mst_branch *mstb; 1752 1753 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1754 if (!mstb) 1755 return -EINVAL; 1756 1757 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1758 if (!txmsg) { 1759 ret = -ENOMEM; 1760 goto fail_put; 1761 } 1762 1763 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes); 1764 txmsg->dst = mstb; 1765 1766 drm_dp_queue_down_tx(mgr, txmsg); 1767 1768 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1769 if (ret > 0) { 1770 if (txmsg->reply.reply_type == 1) { 1771 ret = -EINVAL; 1772 } else 1773 ret = 0; 1774 } 1775 kfree(txmsg); 1776 fail_put: 1777 drm_dp_put_mst_branch_device(mstb); 1778 return ret; 1779 } 1780 1781 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type) 1782 { 1783 struct drm_dp_sideband_msg_reply_body reply; 1784 1785 reply.reply_type = 1; 1786 reply.req_type = req_type; 1787 drm_dp_encode_sideband_reply(&reply, msg); 1788 return 0; 1789 } 1790 1791 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr, 1792 struct drm_dp_mst_branch *mstb, 1793 int req_type, int seqno, bool broadcast) 1794 { 1795 struct drm_dp_sideband_msg_tx *txmsg; 1796 1797 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1798 if (!txmsg) 1799 return -ENOMEM; 1800 1801 txmsg->dst = mstb; 1802 txmsg->seqno = seqno; 1803 drm_dp_encode_up_ack_reply(txmsg, req_type); 1804 1805 mutex_lock(&mgr->qlock); 1806 list_add_tail(&txmsg->next, &mgr->tx_msg_upq); 1807 if (!mgr->tx_up_in_progress) { 1808 process_single_up_tx_qlock(mgr); 1809 } 1810 mutex_unlock(&mgr->qlock); 1811 return 0; 1812 } 1813 1814 static bool drm_dp_get_vc_payload_bw(int dp_link_bw, 1815 int dp_link_count, 1816 int *out) 1817 { 1818 switch (dp_link_bw) { 1819 default: 1820 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n", 1821 dp_link_bw, dp_link_count); 1822 return false; 1823 1824 case DP_LINK_BW_1_62: 1825 *out = 3 * dp_link_count; 1826 break; 1827 case DP_LINK_BW_2_7: 1828 *out = 5 * dp_link_count; 1829 break; 1830 case DP_LINK_BW_5_4: 1831 *out = 10 * dp_link_count; 1832 break; 1833 } 1834 return true; 1835 } 1836 1837 /** 1838 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager 1839 * @mgr: manager to set state for 1840 * @mst_state: true to enable MST on this connector - false to disable. 1841 * 1842 * This is called by the driver when it detects an MST capable device plugged 1843 * into a DP MST capable port, or when a DP MST capable device is unplugged. 1844 */ 1845 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state) 1846 { 1847 int ret = 0; 1848 struct drm_dp_mst_branch *mstb = NULL; 1849 1850 mutex_lock(&mgr->lock); 1851 if (mst_state == mgr->mst_state) 1852 goto out_unlock; 1853 1854 mgr->mst_state = mst_state; 1855 /* set the device into MST mode */ 1856 if (mst_state) { 1857 WARN_ON(mgr->mst_primary); 1858 1859 /* get dpcd info */ 1860 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 1861 if (ret != DP_RECEIVER_CAP_SIZE) { 1862 DRM_DEBUG_KMS("failed to read DPCD\n"); 1863 goto out_unlock; 1864 } 1865 1866 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1], 1867 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK, 1868 &mgr->pbn_div)) { 1869 ret = -EINVAL; 1870 goto out_unlock; 1871 } 1872 1873 mgr->total_pbn = 2560; 1874 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div); 1875 mgr->avail_slots = mgr->total_slots; 1876 1877 /* add initial branch device at LCT 1 */ 1878 mstb = drm_dp_add_mst_branch_device(1, NULL); 1879 if (mstb == NULL) { 1880 ret = -ENOMEM; 1881 goto out_unlock; 1882 } 1883 mstb->mgr = mgr; 1884 1885 /* give this the main reference */ 1886 mgr->mst_primary = mstb; 1887 kref_get(&mgr->mst_primary->kref); 1888 1889 { 1890 struct drm_dp_payload reset_pay; 1891 reset_pay.start_slot = 0; 1892 reset_pay.num_slots = 0x3f; 1893 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay); 1894 } 1895 1896 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 1897 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 1898 if (ret < 0) { 1899 goto out_unlock; 1900 } 1901 1902 1903 /* sort out guid */ 1904 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16); 1905 if (ret != 16) { 1906 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret); 1907 goto out_unlock; 1908 } 1909 1910 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid); 1911 if (!mgr->guid_valid) { 1912 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16); 1913 mgr->guid_valid = true; 1914 } 1915 1916 queue_work(system_long_wq, &mgr->work); 1917 1918 ret = 0; 1919 } else { 1920 /* disable MST on the device */ 1921 mstb = mgr->mst_primary; 1922 mgr->mst_primary = NULL; 1923 /* this can fail if the device is gone */ 1924 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0); 1925 ret = 0; 1926 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload)); 1927 mgr->payload_mask = 0; 1928 set_bit(0, &mgr->payload_mask); 1929 } 1930 1931 out_unlock: 1932 mutex_unlock(&mgr->lock); 1933 if (mstb) 1934 drm_dp_put_mst_branch_device(mstb); 1935 return ret; 1936 1937 } 1938 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst); 1939 1940 /** 1941 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager 1942 * @mgr: manager to suspend 1943 * 1944 * This function tells the MST device that we can't handle UP messages 1945 * anymore. This should stop it from sending any since we are suspended. 1946 */ 1947 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr) 1948 { 1949 mutex_lock(&mgr->lock); 1950 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 1951 DP_MST_EN | DP_UPSTREAM_IS_SRC); 1952 mutex_unlock(&mgr->lock); 1953 flush_work(&mgr->work); 1954 flush_work(&mgr->destroy_connector_work); 1955 } 1956 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend); 1957 1958 /** 1959 * drm_dp_mst_topology_mgr_resume() - resume the MST manager 1960 * @mgr: manager to resume 1961 * 1962 * This will fetch DPCD and see if the device is still there, 1963 * if it is, it will rewrite the MSTM control bits, and return. 1964 * 1965 * if the device fails this returns -1, and the driver should do 1966 * a full MST reprobe, in case we were undocked. 1967 */ 1968 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr) 1969 { 1970 int ret = 0; 1971 1972 mutex_lock(&mgr->lock); 1973 1974 if (mgr->mst_primary) { 1975 int sret; 1976 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 1977 if (sret != DP_RECEIVER_CAP_SIZE) { 1978 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); 1979 ret = -1; 1980 goto out_unlock; 1981 } 1982 1983 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 1984 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 1985 if (ret < 0) { 1986 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n"); 1987 ret = -1; 1988 goto out_unlock; 1989 } 1990 ret = 0; 1991 } else 1992 ret = -1; 1993 1994 out_unlock: 1995 mutex_unlock(&mgr->lock); 1996 return ret; 1997 } 1998 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume); 1999 2000 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up) 2001 { 2002 int len; 2003 u8 replyblock[32]; 2004 int replylen, origlen, curreply; 2005 int ret; 2006 struct drm_dp_sideband_msg_rx *msg; 2007 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE; 2008 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv; 2009 2010 len = min(mgr->max_dpcd_transaction_bytes, 16); 2011 ret = drm_dp_dpcd_read(mgr->aux, basereg, 2012 replyblock, len); 2013 if (ret != len) { 2014 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret); 2015 return; 2016 } 2017 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true); 2018 if (!ret) { 2019 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]); 2020 return; 2021 } 2022 replylen = msg->curchunk_len + msg->curchunk_hdrlen; 2023 2024 origlen = replylen; 2025 replylen -= len; 2026 curreply = len; 2027 while (replylen > 0) { 2028 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16); 2029 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply, 2030 replyblock, len); 2031 if (ret != len) { 2032 DRM_DEBUG_KMS("failed to read a chunk\n"); 2033 } 2034 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false); 2035 if (ret == false) 2036 DRM_DEBUG_KMS("failed to build sideband msg\n"); 2037 curreply += len; 2038 replylen -= len; 2039 } 2040 } 2041 2042 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) 2043 { 2044 int ret = 0; 2045 2046 drm_dp_get_one_sb_msg(mgr, false); 2047 2048 if (mgr->down_rep_recv.have_eomt) { 2049 struct drm_dp_sideband_msg_tx *txmsg; 2050 struct drm_dp_mst_branch *mstb; 2051 int slot = -1; 2052 mstb = drm_dp_get_mst_branch_device(mgr, 2053 mgr->down_rep_recv.initial_hdr.lct, 2054 mgr->down_rep_recv.initial_hdr.rad); 2055 2056 if (!mstb) { 2057 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct); 2058 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2059 return 0; 2060 } 2061 2062 /* find the message */ 2063 slot = mgr->down_rep_recv.initial_hdr.seqno; 2064 mutex_lock(&mgr->qlock); 2065 txmsg = mstb->tx_slots[slot]; 2066 /* remove from slots */ 2067 mutex_unlock(&mgr->qlock); 2068 2069 if (!txmsg) { 2070 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n", 2071 mstb, 2072 mgr->down_rep_recv.initial_hdr.seqno, 2073 mgr->down_rep_recv.initial_hdr.lct, 2074 mgr->down_rep_recv.initial_hdr.rad[0], 2075 mgr->down_rep_recv.msg[0]); 2076 drm_dp_put_mst_branch_device(mstb); 2077 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2078 return 0; 2079 } 2080 2081 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply); 2082 if (txmsg->reply.reply_type == 1) { 2083 DRM_DEBUG_KMS("Got NAK reply: req 0x%02x, reason 0x%02x, nak data 0x%02x\n", txmsg->reply.req_type, txmsg->reply.u.nak.reason, txmsg->reply.u.nak.nak_data); 2084 } 2085 2086 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2087 drm_dp_put_mst_branch_device(mstb); 2088 2089 mutex_lock(&mgr->qlock); 2090 txmsg->state = DRM_DP_SIDEBAND_TX_RX; 2091 mstb->tx_slots[slot] = NULL; 2092 mutex_unlock(&mgr->qlock); 2093 2094 wake_up(&mgr->tx_waitq); 2095 } 2096 return ret; 2097 } 2098 2099 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr) 2100 { 2101 int ret = 0; 2102 drm_dp_get_one_sb_msg(mgr, true); 2103 2104 if (mgr->up_req_recv.have_eomt) { 2105 struct drm_dp_sideband_msg_req_body msg; 2106 struct drm_dp_mst_branch *mstb; 2107 bool seqno; 2108 mstb = drm_dp_get_mst_branch_device(mgr, 2109 mgr->up_req_recv.initial_hdr.lct, 2110 mgr->up_req_recv.initial_hdr.rad); 2111 if (!mstb) { 2112 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2113 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2114 return 0; 2115 } 2116 2117 seqno = mgr->up_req_recv.initial_hdr.seqno; 2118 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg); 2119 2120 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) { 2121 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false); 2122 drm_dp_update_port(mstb, &msg.u.conn_stat); 2123 DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg.u.conn_stat.port_number, msg.u.conn_stat.legacy_device_plug_status, msg.u.conn_stat.displayport_device_plug_status, msg.u.conn_stat.message_capability_status, msg.u.conn_stat.input_port, msg.u.conn_stat.peer_device_type); 2124 (*mgr->cbs->hotplug)(mgr); 2125 2126 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) { 2127 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false); 2128 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn); 2129 } 2130 2131 drm_dp_put_mst_branch_device(mstb); 2132 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2133 } 2134 return ret; 2135 } 2136 2137 /** 2138 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify 2139 * @mgr: manager to notify irq for. 2140 * @esi: 4 bytes from SINK_COUNT_ESI 2141 * 2142 * This should be called from the driver when it detects a short IRQ, 2143 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The 2144 * topology manager will process the sideband messages received as a result 2145 * of this. 2146 */ 2147 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled) 2148 { 2149 int ret = 0; 2150 int sc; 2151 *handled = false; 2152 sc = esi[0] & 0x3f; 2153 2154 if (sc != mgr->sink_count) { 2155 mgr->sink_count = sc; 2156 *handled = true; 2157 } 2158 2159 if (esi[1] & DP_DOWN_REP_MSG_RDY) { 2160 ret = drm_dp_mst_handle_down_rep(mgr); 2161 *handled = true; 2162 } 2163 2164 if (esi[1] & DP_UP_REQ_MSG_RDY) { 2165 ret |= drm_dp_mst_handle_up_req(mgr); 2166 *handled = true; 2167 } 2168 2169 drm_dp_mst_kick_tx(mgr); 2170 return ret; 2171 } 2172 EXPORT_SYMBOL(drm_dp_mst_hpd_irq); 2173 2174 /** 2175 * drm_dp_mst_detect_port() - get connection status for an MST port 2176 * @mgr: manager for this port 2177 * @port: unverified pointer to a port 2178 * 2179 * This returns the current connection state for a port. It validates the 2180 * port pointer still exists so the caller doesn't require a reference 2181 */ 2182 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector, 2183 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2184 { 2185 enum drm_connector_status status = connector_status_disconnected; 2186 2187 /* we need to search for the port in the mgr in case its gone */ 2188 port = drm_dp_get_validated_port_ref(mgr, port); 2189 if (!port) 2190 return connector_status_disconnected; 2191 2192 if (!port->ddps) 2193 goto out; 2194 2195 switch (port->pdt) { 2196 case DP_PEER_DEVICE_NONE: 2197 case DP_PEER_DEVICE_MST_BRANCHING: 2198 break; 2199 2200 case DP_PEER_DEVICE_SST_SINK: 2201 status = connector_status_connected; 2202 /* for logical ports - cache the EDID */ 2203 if (port->port_num >= 8 && !port->cached_edid) { 2204 port->cached_edid = drm_get_edid(connector, &port->aux.ddc); 2205 } 2206 break; 2207 case DP_PEER_DEVICE_DP_LEGACY_CONV: 2208 if (port->ldps) 2209 status = connector_status_connected; 2210 break; 2211 } 2212 out: 2213 drm_dp_put_port(port); 2214 return status; 2215 } 2216 EXPORT_SYMBOL(drm_dp_mst_detect_port); 2217 2218 /** 2219 * drm_dp_mst_get_edid() - get EDID for an MST port 2220 * @connector: toplevel connector to get EDID for 2221 * @mgr: manager for this port 2222 * @port: unverified pointer to a port. 2223 * 2224 * This returns an EDID for the port connected to a connector, 2225 * It validates the pointer still exists so the caller doesn't require a 2226 * reference. 2227 */ 2228 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2229 { 2230 struct edid *edid = NULL; 2231 2232 /* we need to search for the port in the mgr in case its gone */ 2233 port = drm_dp_get_validated_port_ref(mgr, port); 2234 if (!port) 2235 return NULL; 2236 2237 if (port->cached_edid) 2238 edid = drm_edid_duplicate(port->cached_edid); 2239 else { 2240 edid = drm_get_edid(connector, &port->aux.ddc); 2241 drm_mode_connector_set_tile_property(connector); 2242 } 2243 drm_dp_put_port(port); 2244 return edid; 2245 } 2246 EXPORT_SYMBOL(drm_dp_mst_get_edid); 2247 2248 /** 2249 * drm_dp_find_vcpi_slots() - find slots for this PBN value 2250 * @mgr: manager to use 2251 * @pbn: payload bandwidth to convert into slots. 2252 */ 2253 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, 2254 int pbn) 2255 { 2256 int num_slots; 2257 2258 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2259 2260 if (num_slots > mgr->avail_slots) 2261 return -ENOSPC; 2262 return num_slots; 2263 } 2264 EXPORT_SYMBOL(drm_dp_find_vcpi_slots); 2265 2266 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr, 2267 struct drm_dp_vcpi *vcpi, int pbn) 2268 { 2269 int num_slots; 2270 int ret; 2271 2272 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2273 2274 if (num_slots > mgr->avail_slots) 2275 return -ENOSPC; 2276 2277 vcpi->pbn = pbn; 2278 vcpi->aligned_pbn = num_slots * mgr->pbn_div; 2279 vcpi->num_slots = num_slots; 2280 2281 ret = drm_dp_mst_assign_payload_id(mgr, vcpi); 2282 if (ret < 0) 2283 return ret; 2284 return 0; 2285 } 2286 2287 /** 2288 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel 2289 * @mgr: manager for this port 2290 * @port: port to allocate a virtual channel for. 2291 * @pbn: payload bandwidth number to request 2292 * @slots: returned number of slots for this PBN. 2293 */ 2294 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots) 2295 { 2296 int ret; 2297 2298 port = drm_dp_get_validated_port_ref(mgr, port); 2299 if (!port) 2300 return false; 2301 2302 if (port->vcpi.vcpi > 0) { 2303 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn); 2304 if (pbn == port->vcpi.pbn) { 2305 *slots = port->vcpi.num_slots; 2306 return true; 2307 } 2308 } 2309 2310 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn); 2311 if (ret) { 2312 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret); 2313 goto out; 2314 } 2315 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots); 2316 *slots = port->vcpi.num_slots; 2317 2318 drm_dp_put_port(port); 2319 return true; 2320 out: 2321 return false; 2322 } 2323 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi); 2324 2325 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2326 { 2327 int slots = 0; 2328 port = drm_dp_get_validated_port_ref(mgr, port); 2329 if (!port) 2330 return slots; 2331 2332 slots = port->vcpi.num_slots; 2333 drm_dp_put_port(port); 2334 return slots; 2335 } 2336 EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots); 2337 2338 /** 2339 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI 2340 * @mgr: manager for this port 2341 * @port: unverified pointer to a port. 2342 * 2343 * This just resets the number of slots for the ports VCPI for later programming. 2344 */ 2345 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2346 { 2347 port = drm_dp_get_validated_port_ref(mgr, port); 2348 if (!port) 2349 return; 2350 port->vcpi.num_slots = 0; 2351 drm_dp_put_port(port); 2352 } 2353 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots); 2354 2355 /** 2356 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI 2357 * @mgr: manager for this port 2358 * @port: unverified port to deallocate vcpi for 2359 */ 2360 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2361 { 2362 port = drm_dp_get_validated_port_ref(mgr, port); 2363 if (!port) 2364 return; 2365 2366 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 2367 port->vcpi.num_slots = 0; 2368 port->vcpi.pbn = 0; 2369 port->vcpi.aligned_pbn = 0; 2370 port->vcpi.vcpi = 0; 2371 drm_dp_put_port(port); 2372 } 2373 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi); 2374 2375 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, 2376 int id, struct drm_dp_payload *payload) 2377 { 2378 u8 payload_alloc[3], status; 2379 int ret; 2380 int retries = 0; 2381 2382 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, 2383 DP_PAYLOAD_TABLE_UPDATED); 2384 2385 payload_alloc[0] = id; 2386 payload_alloc[1] = payload->start_slot; 2387 payload_alloc[2] = payload->num_slots; 2388 2389 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3); 2390 if (ret != 3) { 2391 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret); 2392 goto fail; 2393 } 2394 2395 retry: 2396 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2397 if (ret < 0) { 2398 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2399 goto fail; 2400 } 2401 2402 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) { 2403 retries++; 2404 if (retries < 20) { 2405 usleep_range(10000, 20000); 2406 goto retry; 2407 } 2408 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status); 2409 ret = -EINVAL; 2410 goto fail; 2411 } 2412 ret = 0; 2413 fail: 2414 return ret; 2415 } 2416 2417 2418 /** 2419 * drm_dp_check_act_status() - Check ACT handled status. 2420 * @mgr: manager to use 2421 * 2422 * Check the payload status bits in the DPCD for ACT handled completion. 2423 */ 2424 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr) 2425 { 2426 u8 status; 2427 int ret; 2428 int count = 0; 2429 2430 do { 2431 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2432 2433 if (ret < 0) { 2434 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2435 goto fail; 2436 } 2437 2438 if (status & DP_PAYLOAD_ACT_HANDLED) 2439 break; 2440 count++; 2441 udelay(100); 2442 2443 } while (count < 30); 2444 2445 if (!(status & DP_PAYLOAD_ACT_HANDLED)) { 2446 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count); 2447 ret = -EINVAL; 2448 goto fail; 2449 } 2450 return 0; 2451 fail: 2452 return ret; 2453 } 2454 EXPORT_SYMBOL(drm_dp_check_act_status); 2455 2456 /** 2457 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode. 2458 * @clock: dot clock for the mode 2459 * @bpp: bpp for the mode. 2460 * 2461 * This uses the formula in the spec to calculate the PBN value for a mode. 2462 */ 2463 int drm_dp_calc_pbn_mode(int clock, int bpp) 2464 { 2465 fixed20_12 pix_bw; 2466 fixed20_12 fbpp; 2467 fixed20_12 result; 2468 fixed20_12 margin, tmp; 2469 u32 res; 2470 2471 pix_bw.full = dfixed_const(clock); 2472 fbpp.full = dfixed_const(bpp); 2473 tmp.full = dfixed_const(8); 2474 fbpp.full = dfixed_div(fbpp, tmp); 2475 2476 result.full = dfixed_mul(pix_bw, fbpp); 2477 margin.full = dfixed_const(54); 2478 tmp.full = dfixed_const(64); 2479 margin.full = dfixed_div(margin, tmp); 2480 result.full = dfixed_div(result, margin); 2481 2482 margin.full = dfixed_const(1006); 2483 tmp.full = dfixed_const(1000); 2484 margin.full = dfixed_div(margin, tmp); 2485 result.full = dfixed_mul(result, margin); 2486 2487 result.full = dfixed_div(result, tmp); 2488 result.full = dfixed_ceil(result); 2489 res = dfixed_trunc(result); 2490 return res; 2491 } 2492 EXPORT_SYMBOL(drm_dp_calc_pbn_mode); 2493 2494 static int test_calc_pbn_mode(void) 2495 { 2496 int ret; 2497 ret = drm_dp_calc_pbn_mode(154000, 30); 2498 if (ret != 689) 2499 return -EINVAL; 2500 ret = drm_dp_calc_pbn_mode(234000, 30); 2501 if (ret != 1047) 2502 return -EINVAL; 2503 return 0; 2504 } 2505 2506 /* we want to kick the TX after we've ack the up/down IRQs. */ 2507 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr) 2508 { 2509 queue_work(system_long_wq, &mgr->tx_work); 2510 } 2511 2512 static void drm_dp_mst_dump_mstb(struct seq_file *m, 2513 struct drm_dp_mst_branch *mstb) 2514 { 2515 struct drm_dp_mst_port *port; 2516 int tabs = mstb->lct; 2517 char prefix[10]; 2518 int i; 2519 2520 for (i = 0; i < tabs; i++) 2521 prefix[i] = '\t'; 2522 prefix[i] = '\0'; 2523 2524 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports); 2525 list_for_each_entry(port, &mstb->ports, next) { 2526 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector); 2527 if (port->mstb) 2528 drm_dp_mst_dump_mstb(m, port->mstb); 2529 } 2530 } 2531 2532 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 2533 char *buf) 2534 { 2535 int ret; 2536 int i; 2537 for (i = 0; i < 4; i++) { 2538 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16); 2539 if (ret != 16) 2540 break; 2541 } 2542 if (i == 4) 2543 return true; 2544 return false; 2545 } 2546 2547 /** 2548 * drm_dp_mst_dump_topology(): dump topology to seq file. 2549 * @m: seq_file to dump output to 2550 * @mgr: manager to dump current topology for. 2551 * 2552 * helper to dump MST topology to a seq file for debugfs. 2553 */ 2554 void drm_dp_mst_dump_topology(struct seq_file *m, 2555 struct drm_dp_mst_topology_mgr *mgr) 2556 { 2557 int i; 2558 struct drm_dp_mst_port *port; 2559 mutex_lock(&mgr->lock); 2560 if (mgr->mst_primary) 2561 drm_dp_mst_dump_mstb(m, mgr->mst_primary); 2562 2563 /* dump VCPIs */ 2564 mutex_unlock(&mgr->lock); 2565 2566 mutex_lock(&mgr->payload_lock); 2567 seq_printf(m, "vcpi: %lx\n", mgr->payload_mask); 2568 2569 for (i = 0; i < mgr->max_payloads; i++) { 2570 if (mgr->proposed_vcpis[i]) { 2571 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 2572 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots); 2573 } else 2574 seq_printf(m, "vcpi %d:unsed\n", i); 2575 } 2576 for (i = 0; i < mgr->max_payloads; i++) { 2577 seq_printf(m, "payload %d: %d, %d, %d\n", 2578 i, 2579 mgr->payloads[i].payload_state, 2580 mgr->payloads[i].start_slot, 2581 mgr->payloads[i].num_slots); 2582 2583 2584 } 2585 mutex_unlock(&mgr->payload_lock); 2586 2587 mutex_lock(&mgr->lock); 2588 if (mgr->mst_primary) { 2589 u8 buf[64]; 2590 bool bret; 2591 int ret; 2592 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE); 2593 seq_printf(m, "dpcd: "); 2594 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++) 2595 seq_printf(m, "%02x ", buf[i]); 2596 seq_printf(m, "\n"); 2597 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2); 2598 seq_printf(m, "faux/mst: "); 2599 for (i = 0; i < 2; i++) 2600 seq_printf(m, "%02x ", buf[i]); 2601 seq_printf(m, "\n"); 2602 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1); 2603 seq_printf(m, "mst ctrl: "); 2604 for (i = 0; i < 1; i++) 2605 seq_printf(m, "%02x ", buf[i]); 2606 seq_printf(m, "\n"); 2607 2608 /* dump the standard OUI branch header */ 2609 ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE); 2610 seq_printf(m, "branch oui: "); 2611 for (i = 0; i < 0x3; i++) 2612 seq_printf(m, "%02x", buf[i]); 2613 seq_printf(m, " devid: "); 2614 for (i = 0x3; i < 0x8; i++) 2615 seq_printf(m, "%c", buf[i]); 2616 seq_printf(m, " revision: hw: %x.%x sw: %x.%x", buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]); 2617 seq_printf(m, "\n"); 2618 bret = dump_dp_payload_table(mgr, buf); 2619 if (bret == true) { 2620 seq_printf(m, "payload table: "); 2621 for (i = 0; i < 63; i++) 2622 seq_printf(m, "%02x ", buf[i]); 2623 seq_printf(m, "\n"); 2624 } 2625 2626 } 2627 2628 mutex_unlock(&mgr->lock); 2629 2630 } 2631 EXPORT_SYMBOL(drm_dp_mst_dump_topology); 2632 2633 static void drm_dp_tx_work(struct work_struct *work) 2634 { 2635 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work); 2636 2637 mutex_lock(&mgr->qlock); 2638 if (mgr->tx_down_in_progress) 2639 process_single_down_tx_qlock(mgr); 2640 mutex_unlock(&mgr->qlock); 2641 } 2642 2643 static void drm_dp_destroy_connector_work(struct work_struct *work) 2644 { 2645 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work); 2646 struct drm_dp_mst_port *port; 2647 bool send_hotplug = false; 2648 /* 2649 * Not a regular list traverse as we have to drop the destroy 2650 * connector lock before destroying the connector, to avoid AB->BA 2651 * ordering between this lock and the config mutex. 2652 */ 2653 for (;;) { 2654 mutex_lock(&mgr->destroy_connector_lock); 2655 port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next); 2656 if (!port) { 2657 mutex_unlock(&mgr->destroy_connector_lock); 2658 break; 2659 } 2660 list_del(&port->next); 2661 mutex_unlock(&mgr->destroy_connector_lock); 2662 2663 mgr->cbs->destroy_connector(mgr, port->connector); 2664 2665 drm_dp_port_teardown_pdt(port, port->pdt); 2666 2667 if (!port->input && port->vcpi.vcpi > 0) 2668 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 2669 kfree(port); 2670 send_hotplug = true; 2671 } 2672 if (send_hotplug) 2673 (*mgr->cbs->hotplug)(mgr); 2674 } 2675 2676 /** 2677 * drm_dp_mst_topology_mgr_init - initialise a topology manager 2678 * @mgr: manager struct to initialise 2679 * @dev: device providing this structure - for i2c addition. 2680 * @aux: DP helper aux channel to talk to this device 2681 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit 2682 * @max_payloads: maximum number of payloads this GPU can source 2683 * @conn_base_id: the connector object ID the MST device is connected to. 2684 * 2685 * Return 0 for success, or negative error code on failure 2686 */ 2687 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, 2688 struct device *dev, struct drm_dp_aux *aux, 2689 int max_dpcd_transaction_bytes, 2690 int max_payloads, int conn_base_id) 2691 { 2692 mutex_init(&mgr->lock); 2693 mutex_init(&mgr->qlock); 2694 mutex_init(&mgr->payload_lock); 2695 mutex_init(&mgr->destroy_connector_lock); 2696 INIT_LIST_HEAD(&mgr->tx_msg_upq); 2697 INIT_LIST_HEAD(&mgr->tx_msg_downq); 2698 INIT_LIST_HEAD(&mgr->destroy_connector_list); 2699 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); 2700 INIT_WORK(&mgr->tx_work, drm_dp_tx_work); 2701 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work); 2702 init_waitqueue_head(&mgr->tx_waitq); 2703 mgr->dev = dev; 2704 mgr->aux = aux; 2705 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes; 2706 mgr->max_payloads = max_payloads; 2707 mgr->conn_base_id = conn_base_id; 2708 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL); 2709 if (!mgr->payloads) 2710 return -ENOMEM; 2711 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL); 2712 if (!mgr->proposed_vcpis) 2713 return -ENOMEM; 2714 set_bit(0, &mgr->payload_mask); 2715 test_calc_pbn_mode(); 2716 return 0; 2717 } 2718 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init); 2719 2720 /** 2721 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager. 2722 * @mgr: manager to destroy 2723 */ 2724 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) 2725 { 2726 flush_work(&mgr->work); 2727 flush_work(&mgr->destroy_connector_work); 2728 mutex_lock(&mgr->payload_lock); 2729 kfree(mgr->payloads); 2730 mgr->payloads = NULL; 2731 kfree(mgr->proposed_vcpis); 2732 mgr->proposed_vcpis = NULL; 2733 mutex_unlock(&mgr->payload_lock); 2734 mgr->dev = NULL; 2735 mgr->aux = NULL; 2736 } 2737 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy); 2738 2739 /* I2C device */ 2740 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 2741 int num) 2742 { 2743 struct drm_dp_aux *aux = adapter->algo_data; 2744 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux); 2745 struct drm_dp_mst_branch *mstb; 2746 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 2747 unsigned int i; 2748 bool reading = false; 2749 struct drm_dp_sideband_msg_req_body msg; 2750 struct drm_dp_sideband_msg_tx *txmsg = NULL; 2751 int ret; 2752 2753 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 2754 if (!mstb) 2755 return -EREMOTEIO; 2756 2757 /* construct i2c msg */ 2758 /* see if last msg is a read */ 2759 if (msgs[num - 1].flags & I2C_M_RD) 2760 reading = true; 2761 2762 if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) { 2763 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n"); 2764 ret = -EIO; 2765 goto out; 2766 } 2767 2768 memset(&msg, 0, sizeof(msg)); 2769 msg.req_type = DP_REMOTE_I2C_READ; 2770 msg.u.i2c_read.num_transactions = num - 1; 2771 msg.u.i2c_read.port_number = port->port_num; 2772 for (i = 0; i < num - 1; i++) { 2773 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr; 2774 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len; 2775 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf; 2776 } 2777 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr; 2778 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len; 2779 2780 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 2781 if (!txmsg) { 2782 ret = -ENOMEM; 2783 goto out; 2784 } 2785 2786 txmsg->dst = mstb; 2787 drm_dp_encode_sideband_req(&msg, txmsg); 2788 2789 drm_dp_queue_down_tx(mgr, txmsg); 2790 2791 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 2792 if (ret > 0) { 2793 2794 if (txmsg->reply.reply_type == 1) { /* got a NAK back */ 2795 ret = -EREMOTEIO; 2796 goto out; 2797 } 2798 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) { 2799 ret = -EIO; 2800 goto out; 2801 } 2802 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len); 2803 ret = num; 2804 } 2805 out: 2806 kfree(txmsg); 2807 drm_dp_put_mst_branch_device(mstb); 2808 return ret; 2809 } 2810 2811 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter) 2812 { 2813 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | 2814 I2C_FUNC_SMBUS_READ_BLOCK_DATA | 2815 I2C_FUNC_SMBUS_BLOCK_PROC_CALL | 2816 I2C_FUNC_10BIT_ADDR; 2817 } 2818 2819 static const struct i2c_algorithm drm_dp_mst_i2c_algo = { 2820 .functionality = drm_dp_mst_i2c_functionality, 2821 .master_xfer = drm_dp_mst_i2c_xfer, 2822 }; 2823 2824 /** 2825 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX 2826 * @aux: DisplayPort AUX channel 2827 * 2828 * Returns 0 on success or a negative error code on failure. 2829 */ 2830 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux) 2831 { 2832 aux->ddc.algo = &drm_dp_mst_i2c_algo; 2833 aux->ddc.algo_data = aux; 2834 aux->ddc.retries = 3; 2835 2836 aux->ddc.class = I2C_CLASS_DDC; 2837 aux->ddc.owner = THIS_MODULE; 2838 aux->ddc.dev.parent = aux->dev; 2839 aux->ddc.dev.of_node = aux->dev->of_node; 2840 2841 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev), 2842 sizeof(aux->ddc.name)); 2843 2844 return i2c_add_adapter(&aux->ddc); 2845 } 2846 2847 /** 2848 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter 2849 * @aux: DisplayPort AUX channel 2850 */ 2851 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux) 2852 { 2853 i2c_del_adapter(&aux->ddc); 2854 } 2855