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 int 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 cancel_work_sync(&mstb->mgr->work); 788 789 /* 790 * destroy all ports - don't need lock 791 * as there are no more references to the mst branch 792 * device at this point. 793 */ 794 list_for_each_entry_safe(port, tmp, &mstb->ports, next) { 795 list_del(&port->next); 796 drm_dp_put_port(port); 797 } 798 799 /* drop any tx slots msg */ 800 mutex_lock(&mstb->mgr->qlock); 801 if (mstb->tx_slots[0]) { 802 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 803 mstb->tx_slots[0] = NULL; 804 wake_tx = true; 805 } 806 if (mstb->tx_slots[1]) { 807 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 808 mstb->tx_slots[1] = NULL; 809 wake_tx = true; 810 } 811 mutex_unlock(&mstb->mgr->qlock); 812 813 if (wake_tx) 814 wake_up(&mstb->mgr->tx_waitq); 815 kfree(mstb); 816 } 817 818 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb) 819 { 820 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device); 821 } 822 823 824 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt) 825 { 826 struct drm_dp_mst_branch *mstb; 827 828 switch (old_pdt) { 829 case DP_PEER_DEVICE_DP_LEGACY_CONV: 830 case DP_PEER_DEVICE_SST_SINK: 831 /* remove i2c over sideband */ 832 drm_dp_mst_unregister_i2c_bus(&port->aux); 833 break; 834 case DP_PEER_DEVICE_MST_BRANCHING: 835 mstb = port->mstb; 836 port->mstb = NULL; 837 drm_dp_put_mst_branch_device(mstb); 838 break; 839 } 840 } 841 842 static void drm_dp_destroy_port(struct kref *kref) 843 { 844 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref); 845 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 846 if (!port->input) { 847 port->vcpi.num_slots = 0; 848 849 kfree(port->cached_edid); 850 if (port->connector) 851 (*port->mgr->cbs->destroy_connector)(mgr, port->connector); 852 drm_dp_port_teardown_pdt(port, port->pdt); 853 854 if (!port->input && port->vcpi.vcpi > 0) 855 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 856 } 857 kfree(port); 858 859 (*mgr->cbs->hotplug)(mgr); 860 } 861 862 static void drm_dp_put_port(struct drm_dp_mst_port *port) 863 { 864 kref_put(&port->kref, drm_dp_destroy_port); 865 } 866 867 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) 868 { 869 struct drm_dp_mst_port *port; 870 struct drm_dp_mst_branch *rmstb; 871 if (to_find == mstb) { 872 kref_get(&mstb->kref); 873 return mstb; 874 } 875 list_for_each_entry(port, &mstb->ports, next) { 876 if (port->mstb) { 877 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find); 878 if (rmstb) 879 return rmstb; 880 } 881 } 882 return NULL; 883 } 884 885 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) 886 { 887 struct drm_dp_mst_branch *rmstb = NULL; 888 mutex_lock(&mgr->lock); 889 if (mgr->mst_primary) 890 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb); 891 mutex_unlock(&mgr->lock); 892 return rmstb; 893 } 894 895 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) 896 { 897 struct drm_dp_mst_port *port, *mport; 898 899 list_for_each_entry(port, &mstb->ports, next) { 900 if (port == to_find) { 901 kref_get(&port->kref); 902 return port; 903 } 904 if (port->mstb) { 905 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find); 906 if (mport) 907 return mport; 908 } 909 } 910 return NULL; 911 } 912 913 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) 914 { 915 struct drm_dp_mst_port *rport = NULL; 916 mutex_lock(&mgr->lock); 917 if (mgr->mst_primary) 918 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port); 919 mutex_unlock(&mgr->lock); 920 return rport; 921 } 922 923 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num) 924 { 925 struct drm_dp_mst_port *port; 926 927 list_for_each_entry(port, &mstb->ports, next) { 928 if (port->port_num == port_num) { 929 kref_get(&port->kref); 930 return port; 931 } 932 } 933 934 return NULL; 935 } 936 937 /* 938 * calculate a new RAD for this MST branch device 939 * if parent has an LCT of 2 then it has 1 nibble of RAD, 940 * if parent has an LCT of 3 then it has 2 nibbles of RAD, 941 */ 942 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port, 943 u8 *rad) 944 { 945 int lct = port->parent->lct; 946 int shift = 4; 947 int idx = lct / 2; 948 if (lct > 1) { 949 memcpy(rad, port->parent->rad, idx); 950 shift = (lct % 2) ? 4 : 0; 951 } else 952 rad[0] = 0; 953 954 rad[idx] |= port->port_num << shift; 955 return lct + 1; 956 } 957 958 /* 959 * return sends link address for new mstb 960 */ 961 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) 962 { 963 int ret; 964 u8 rad[6], lct; 965 bool send_link = false; 966 switch (port->pdt) { 967 case DP_PEER_DEVICE_DP_LEGACY_CONV: 968 case DP_PEER_DEVICE_SST_SINK: 969 /* add i2c over sideband */ 970 ret = drm_dp_mst_register_i2c_bus(&port->aux); 971 break; 972 case DP_PEER_DEVICE_MST_BRANCHING: 973 lct = drm_dp_calculate_rad(port, rad); 974 975 port->mstb = drm_dp_add_mst_branch_device(lct, rad); 976 port->mstb->mgr = port->mgr; 977 port->mstb->port_parent = port; 978 979 send_link = true; 980 break; 981 } 982 return send_link; 983 } 984 985 static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb, 986 struct drm_dp_mst_port *port) 987 { 988 int ret; 989 if (port->dpcd_rev >= 0x12) { 990 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid); 991 if (!port->guid_valid) { 992 ret = drm_dp_send_dpcd_write(mstb->mgr, 993 port, 994 DP_GUID, 995 16, port->guid); 996 port->guid_valid = true; 997 } 998 } 999 } 1000 1001 static void build_mst_prop_path(struct drm_dp_mst_port *port, 1002 struct drm_dp_mst_branch *mstb, 1003 char *proppath, 1004 size_t proppath_size) 1005 { 1006 int i; 1007 char temp[8]; 1008 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id); 1009 for (i = 0; i < (mstb->lct - 1); i++) { 1010 int shift = (i % 2) ? 0 : 4; 1011 int port_num = mstb->rad[i / 2] >> shift; 1012 snprintf(temp, sizeof(temp), "-%d", port_num); 1013 strlcat(proppath, temp, proppath_size); 1014 } 1015 snprintf(temp, sizeof(temp), "-%d", port->port_num); 1016 strlcat(proppath, temp, proppath_size); 1017 } 1018 1019 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb, 1020 struct device *dev, 1021 struct drm_dp_link_addr_reply_port *port_msg) 1022 { 1023 struct drm_dp_mst_port *port; 1024 bool ret; 1025 bool created = false; 1026 int old_pdt = 0; 1027 int old_ddps = 0; 1028 port = drm_dp_get_port(mstb, port_msg->port_number); 1029 if (!port) { 1030 port = kzalloc(sizeof(*port), GFP_KERNEL); 1031 if (!port) 1032 return; 1033 kref_init(&port->kref); 1034 port->parent = mstb; 1035 port->port_num = port_msg->port_number; 1036 port->mgr = mstb->mgr; 1037 port->aux.name = "DPMST"; 1038 port->aux.dev = dev; 1039 created = true; 1040 } else { 1041 old_pdt = port->pdt; 1042 old_ddps = port->ddps; 1043 } 1044 1045 port->pdt = port_msg->peer_device_type; 1046 port->input = port_msg->input_port; 1047 port->mcs = port_msg->mcs; 1048 port->ddps = port_msg->ddps; 1049 port->ldps = port_msg->legacy_device_plug_status; 1050 port->dpcd_rev = port_msg->dpcd_revision; 1051 port->num_sdp_streams = port_msg->num_sdp_streams; 1052 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks; 1053 memcpy(port->guid, port_msg->peer_guid, 16); 1054 1055 /* manage mstb port lists with mgr lock - take a reference 1056 for this list */ 1057 if (created) { 1058 mutex_lock(&mstb->mgr->lock); 1059 kref_get(&port->kref); 1060 list_add(&port->next, &mstb->ports); 1061 mutex_unlock(&mstb->mgr->lock); 1062 } 1063 1064 if (old_ddps != port->ddps) { 1065 if (port->ddps) { 1066 drm_dp_check_port_guid(mstb, port); 1067 if (!port->input) 1068 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port); 1069 } else { 1070 port->guid_valid = false; 1071 port->available_pbn = 0; 1072 } 1073 } 1074 1075 if (old_pdt != port->pdt && !port->input) { 1076 drm_dp_port_teardown_pdt(port, old_pdt); 1077 1078 ret = drm_dp_port_setup_pdt(port); 1079 if (ret == true) { 1080 drm_dp_send_link_address(mstb->mgr, port->mstb); 1081 port->mstb->link_address_sent = true; 1082 } 1083 } 1084 1085 if (created && !port->input) { 1086 char proppath[255]; 1087 build_mst_prop_path(port, mstb, proppath, sizeof(proppath)); 1088 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath); 1089 1090 if (port->port_num >= 8) { 1091 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc); 1092 } 1093 } 1094 1095 /* put reference to this port */ 1096 drm_dp_put_port(port); 1097 } 1098 1099 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb, 1100 struct drm_dp_connection_status_notify *conn_stat) 1101 { 1102 struct drm_dp_mst_port *port; 1103 int old_pdt; 1104 int old_ddps; 1105 bool dowork = false; 1106 port = drm_dp_get_port(mstb, conn_stat->port_number); 1107 if (!port) 1108 return; 1109 1110 old_ddps = port->ddps; 1111 old_pdt = port->pdt; 1112 port->pdt = conn_stat->peer_device_type; 1113 port->mcs = conn_stat->message_capability_status; 1114 port->ldps = conn_stat->legacy_device_plug_status; 1115 port->ddps = conn_stat->displayport_device_plug_status; 1116 1117 if (old_ddps != port->ddps) { 1118 if (port->ddps) { 1119 drm_dp_check_port_guid(mstb, port); 1120 dowork = true; 1121 } else { 1122 port->guid_valid = false; 1123 port->available_pbn = 0; 1124 } 1125 } 1126 if (old_pdt != port->pdt && !port->input) { 1127 drm_dp_port_teardown_pdt(port, old_pdt); 1128 1129 if (drm_dp_port_setup_pdt(port)) 1130 dowork = true; 1131 } 1132 1133 drm_dp_put_port(port); 1134 if (dowork) 1135 queue_work(system_long_wq, &mstb->mgr->work); 1136 1137 } 1138 1139 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr, 1140 u8 lct, u8 *rad) 1141 { 1142 struct drm_dp_mst_branch *mstb; 1143 struct drm_dp_mst_port *port; 1144 int i; 1145 /* find the port by iterating down */ 1146 mstb = mgr->mst_primary; 1147 1148 for (i = 0; i < lct - 1; i++) { 1149 int shift = (i % 2) ? 0 : 4; 1150 int port_num = rad[i / 2] >> shift; 1151 1152 list_for_each_entry(port, &mstb->ports, next) { 1153 if (port->port_num == port_num) { 1154 if (!port->mstb) { 1155 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]); 1156 return NULL; 1157 } 1158 1159 mstb = port->mstb; 1160 break; 1161 } 1162 } 1163 } 1164 kref_get(&mstb->kref); 1165 return mstb; 1166 } 1167 1168 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1169 struct drm_dp_mst_branch *mstb) 1170 { 1171 struct drm_dp_mst_port *port; 1172 1173 if (!mstb->link_address_sent) { 1174 drm_dp_send_link_address(mgr, mstb); 1175 mstb->link_address_sent = true; 1176 } 1177 list_for_each_entry(port, &mstb->ports, next) { 1178 if (port->input) 1179 continue; 1180 1181 if (!port->ddps) 1182 continue; 1183 1184 if (!port->available_pbn) 1185 drm_dp_send_enum_path_resources(mgr, mstb, port); 1186 1187 if (port->mstb) 1188 drm_dp_check_and_send_link_address(mgr, port->mstb); 1189 } 1190 } 1191 1192 static void drm_dp_mst_link_probe_work(struct work_struct *work) 1193 { 1194 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work); 1195 1196 drm_dp_check_and_send_link_address(mgr, mgr->mst_primary); 1197 1198 } 1199 1200 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, 1201 u8 *guid) 1202 { 1203 static u8 zero_guid[16]; 1204 1205 if (!memcmp(guid, zero_guid, 16)) { 1206 u64 salt = get_jiffies_64(); 1207 memcpy(&guid[0], &salt, sizeof(u64)); 1208 memcpy(&guid[8], &salt, sizeof(u64)); 1209 return false; 1210 } 1211 return true; 1212 } 1213 1214 #if 0 1215 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes) 1216 { 1217 struct drm_dp_sideband_msg_req_body req; 1218 1219 req.req_type = DP_REMOTE_DPCD_READ; 1220 req.u.dpcd_read.port_number = port_num; 1221 req.u.dpcd_read.dpcd_address = offset; 1222 req.u.dpcd_read.num_bytes = num_bytes; 1223 drm_dp_encode_sideband_req(&req, msg); 1224 1225 return 0; 1226 } 1227 #endif 1228 1229 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr, 1230 bool up, u8 *msg, int len) 1231 { 1232 int ret; 1233 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE; 1234 int tosend, total, offset; 1235 int retries = 0; 1236 1237 retry: 1238 total = len; 1239 offset = 0; 1240 do { 1241 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total); 1242 1243 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset, 1244 &msg[offset], 1245 tosend); 1246 if (ret != tosend) { 1247 if (ret == -EIO && retries < 5) { 1248 retries++; 1249 goto retry; 1250 } 1251 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret); 1252 WARN(1, "fail\n"); 1253 1254 return -EIO; 1255 } 1256 offset += tosend; 1257 total -= tosend; 1258 } while (total > 0); 1259 return 0; 1260 } 1261 1262 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr, 1263 struct drm_dp_sideband_msg_tx *txmsg) 1264 { 1265 struct drm_dp_mst_branch *mstb = txmsg->dst; 1266 1267 /* both msg slots are full */ 1268 if (txmsg->seqno == -1) { 1269 if (mstb->tx_slots[0] && mstb->tx_slots[1]) { 1270 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__); 1271 return -EAGAIN; 1272 } 1273 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) { 1274 txmsg->seqno = mstb->last_seqno; 1275 mstb->last_seqno ^= 1; 1276 } else if (mstb->tx_slots[0] == NULL) 1277 txmsg->seqno = 0; 1278 else 1279 txmsg->seqno = 1; 1280 mstb->tx_slots[txmsg->seqno] = txmsg; 1281 } 1282 hdr->broadcast = 0; 1283 hdr->path_msg = txmsg->path_msg; 1284 hdr->lct = mstb->lct; 1285 hdr->lcr = mstb->lct - 1; 1286 if (mstb->lct > 1) 1287 memcpy(hdr->rad, mstb->rad, mstb->lct / 2); 1288 hdr->seqno = txmsg->seqno; 1289 return 0; 1290 } 1291 /* 1292 * process a single block of the next message in the sideband queue 1293 */ 1294 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, 1295 struct drm_dp_sideband_msg_tx *txmsg, 1296 bool up) 1297 { 1298 u8 chunk[48]; 1299 struct drm_dp_sideband_msg_hdr hdr; 1300 int len, space, idx, tosend; 1301 int ret; 1302 1303 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr)); 1304 1305 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) { 1306 txmsg->seqno = -1; 1307 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND; 1308 } 1309 1310 /* make hdr from dst mst - for replies use seqno 1311 otherwise assign one */ 1312 ret = set_hdr_from_dst_qlock(&hdr, txmsg); 1313 if (ret < 0) 1314 return ret; 1315 1316 /* amount left to send in this message */ 1317 len = txmsg->cur_len - txmsg->cur_offset; 1318 1319 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */ 1320 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr); 1321 1322 tosend = min(len, space); 1323 if (len == txmsg->cur_len) 1324 hdr.somt = 1; 1325 if (space >= len) 1326 hdr.eomt = 1; 1327 1328 1329 hdr.msg_len = tosend + 1; 1330 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx); 1331 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend); 1332 /* add crc at end */ 1333 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend); 1334 idx += tosend + 1; 1335 1336 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx); 1337 if (ret) { 1338 DRM_DEBUG_KMS("sideband msg failed to send\n"); 1339 return ret; 1340 } 1341 1342 txmsg->cur_offset += tosend; 1343 if (txmsg->cur_offset == txmsg->cur_len) { 1344 txmsg->state = DRM_DP_SIDEBAND_TX_SENT; 1345 return 1; 1346 } 1347 return 0; 1348 } 1349 1350 /* must be called holding qlock */ 1351 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) 1352 { 1353 struct drm_dp_sideband_msg_tx *txmsg; 1354 int ret; 1355 1356 /* construct a chunk from the first msg in the tx_msg queue */ 1357 if (list_empty(&mgr->tx_msg_downq)) { 1358 mgr->tx_down_in_progress = false; 1359 return; 1360 } 1361 mgr->tx_down_in_progress = true; 1362 1363 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next); 1364 ret = process_single_tx_qlock(mgr, txmsg, false); 1365 if (ret == 1) { 1366 /* txmsg is sent it should be in the slots now */ 1367 list_del(&txmsg->next); 1368 } else if (ret) { 1369 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1370 list_del(&txmsg->next); 1371 if (txmsg->seqno != -1) 1372 txmsg->dst->tx_slots[txmsg->seqno] = NULL; 1373 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 1374 wake_up(&mgr->tx_waitq); 1375 } 1376 if (list_empty(&mgr->tx_msg_downq)) { 1377 mgr->tx_down_in_progress = false; 1378 return; 1379 } 1380 } 1381 1382 /* called holding qlock */ 1383 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) 1384 { 1385 struct drm_dp_sideband_msg_tx *txmsg; 1386 int ret; 1387 1388 /* construct a chunk from the first msg in the tx_msg queue */ 1389 if (list_empty(&mgr->tx_msg_upq)) { 1390 mgr->tx_up_in_progress = false; 1391 return; 1392 } 1393 1394 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next); 1395 ret = process_single_tx_qlock(mgr, txmsg, true); 1396 if (ret == 1) { 1397 /* up txmsgs aren't put in slots - so free after we send it */ 1398 list_del(&txmsg->next); 1399 kfree(txmsg); 1400 } else if (ret) 1401 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1402 mgr->tx_up_in_progress = true; 1403 } 1404 1405 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr, 1406 struct drm_dp_sideband_msg_tx *txmsg) 1407 { 1408 mutex_lock(&mgr->qlock); 1409 list_add_tail(&txmsg->next, &mgr->tx_msg_downq); 1410 if (!mgr->tx_down_in_progress) 1411 process_single_down_tx_qlock(mgr); 1412 mutex_unlock(&mgr->qlock); 1413 } 1414 1415 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1416 struct drm_dp_mst_branch *mstb) 1417 { 1418 int len; 1419 struct drm_dp_sideband_msg_tx *txmsg; 1420 int ret; 1421 1422 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1423 if (!txmsg) 1424 return -ENOMEM; 1425 1426 txmsg->dst = mstb; 1427 len = build_link_address(txmsg); 1428 1429 drm_dp_queue_down_tx(mgr, txmsg); 1430 1431 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1432 if (ret > 0) { 1433 int i; 1434 1435 if (txmsg->reply.reply_type == 1) 1436 DRM_DEBUG_KMS("link address nak received\n"); 1437 else { 1438 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports); 1439 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1440 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, 1441 txmsg->reply.u.link_addr.ports[i].input_port, 1442 txmsg->reply.u.link_addr.ports[i].peer_device_type, 1443 txmsg->reply.u.link_addr.ports[i].port_number, 1444 txmsg->reply.u.link_addr.ports[i].dpcd_revision, 1445 txmsg->reply.u.link_addr.ports[i].mcs, 1446 txmsg->reply.u.link_addr.ports[i].ddps, 1447 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status, 1448 txmsg->reply.u.link_addr.ports[i].num_sdp_streams, 1449 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks); 1450 } 1451 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1452 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]); 1453 } 1454 (*mgr->cbs->hotplug)(mgr); 1455 } 1456 } else 1457 DRM_DEBUG_KMS("link address failed %d\n", ret); 1458 1459 kfree(txmsg); 1460 return 0; 1461 } 1462 1463 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, 1464 struct drm_dp_mst_branch *mstb, 1465 struct drm_dp_mst_port *port) 1466 { 1467 int len; 1468 struct drm_dp_sideband_msg_tx *txmsg; 1469 int ret; 1470 1471 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1472 if (!txmsg) 1473 return -ENOMEM; 1474 1475 txmsg->dst = mstb; 1476 len = build_enum_path_resources(txmsg, port->port_num); 1477 1478 drm_dp_queue_down_tx(mgr, txmsg); 1479 1480 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1481 if (ret > 0) { 1482 if (txmsg->reply.reply_type == 1) 1483 DRM_DEBUG_KMS("enum path resources nak received\n"); 1484 else { 1485 if (port->port_num != txmsg->reply.u.path_resources.port_number) 1486 DRM_ERROR("got incorrect port in response\n"); 1487 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, 1488 txmsg->reply.u.path_resources.avail_payload_bw_number); 1489 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number; 1490 } 1491 } 1492 1493 kfree(txmsg); 1494 return 0; 1495 } 1496 1497 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr, 1498 struct drm_dp_mst_port *port, 1499 int id, 1500 int pbn) 1501 { 1502 struct drm_dp_sideband_msg_tx *txmsg; 1503 struct drm_dp_mst_branch *mstb; 1504 int len, ret; 1505 1506 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1507 if (!mstb) 1508 return -EINVAL; 1509 1510 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1511 if (!txmsg) { 1512 ret = -ENOMEM; 1513 goto fail_put; 1514 } 1515 1516 txmsg->dst = mstb; 1517 len = build_allocate_payload(txmsg, port->port_num, 1518 id, 1519 pbn); 1520 1521 drm_dp_queue_down_tx(mgr, txmsg); 1522 1523 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1524 if (ret > 0) { 1525 if (txmsg->reply.reply_type == 1) { 1526 ret = -EINVAL; 1527 } else 1528 ret = 0; 1529 } 1530 kfree(txmsg); 1531 fail_put: 1532 drm_dp_put_mst_branch_device(mstb); 1533 return ret; 1534 } 1535 1536 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1537 int id, 1538 struct drm_dp_payload *payload) 1539 { 1540 int ret; 1541 1542 ret = drm_dp_dpcd_write_payload(mgr, id, payload); 1543 if (ret < 0) { 1544 payload->payload_state = 0; 1545 return ret; 1546 } 1547 payload->payload_state = DP_PAYLOAD_LOCAL; 1548 return 0; 1549 } 1550 1551 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1552 struct drm_dp_mst_port *port, 1553 int id, 1554 struct drm_dp_payload *payload) 1555 { 1556 int ret; 1557 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn); 1558 if (ret < 0) 1559 return ret; 1560 payload->payload_state = DP_PAYLOAD_REMOTE; 1561 return ret; 1562 } 1563 1564 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1565 struct drm_dp_mst_port *port, 1566 int id, 1567 struct drm_dp_payload *payload) 1568 { 1569 DRM_DEBUG_KMS("\n"); 1570 /* its okay for these to fail */ 1571 if (port) { 1572 drm_dp_payload_send_msg(mgr, port, id, 0); 1573 } 1574 1575 drm_dp_dpcd_write_payload(mgr, id, payload); 1576 payload->payload_state = 0; 1577 return 0; 1578 } 1579 1580 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1581 int id, 1582 struct drm_dp_payload *payload) 1583 { 1584 payload->payload_state = 0; 1585 return 0; 1586 } 1587 1588 /** 1589 * drm_dp_update_payload_part1() - Execute payload update part 1 1590 * @mgr: manager to use. 1591 * 1592 * This iterates over all proposed virtual channels, and tries to 1593 * allocate space in the link for them. For 0->slots transitions, 1594 * this step just writes the VCPI to the MST device. For slots->0 1595 * transitions, this writes the updated VCPIs and removes the 1596 * remote VC payloads. 1597 * 1598 * after calling this the driver should generate ACT and payload 1599 * packets. 1600 */ 1601 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr) 1602 { 1603 int i; 1604 int cur_slots = 1; 1605 struct drm_dp_payload req_payload; 1606 struct drm_dp_mst_port *port; 1607 1608 mutex_lock(&mgr->payload_lock); 1609 for (i = 0; i < mgr->max_payloads; i++) { 1610 /* solve the current payloads - compare to the hw ones 1611 - update the hw view */ 1612 req_payload.start_slot = cur_slots; 1613 if (mgr->proposed_vcpis[i]) { 1614 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1615 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots; 1616 } else { 1617 port = NULL; 1618 req_payload.num_slots = 0; 1619 } 1620 /* work out what is required to happen with this payload */ 1621 if (mgr->payloads[i].start_slot != req_payload.start_slot || 1622 mgr->payloads[i].num_slots != req_payload.num_slots) { 1623 1624 /* need to push an update for this payload */ 1625 if (req_payload.num_slots) { 1626 drm_dp_create_payload_step1(mgr, i + 1, &req_payload); 1627 mgr->payloads[i].num_slots = req_payload.num_slots; 1628 } else if (mgr->payloads[i].num_slots) { 1629 mgr->payloads[i].num_slots = 0; 1630 drm_dp_destroy_payload_step1(mgr, port, i + 1, &mgr->payloads[i]); 1631 req_payload.payload_state = mgr->payloads[i].payload_state; 1632 } else 1633 req_payload.payload_state = 0; 1634 1635 mgr->payloads[i].start_slot = req_payload.start_slot; 1636 mgr->payloads[i].payload_state = req_payload.payload_state; 1637 } 1638 cur_slots += req_payload.num_slots; 1639 } 1640 mutex_unlock(&mgr->payload_lock); 1641 1642 return 0; 1643 } 1644 EXPORT_SYMBOL(drm_dp_update_payload_part1); 1645 1646 /** 1647 * drm_dp_update_payload_part2() - Execute payload update part 2 1648 * @mgr: manager to use. 1649 * 1650 * This iterates over all proposed virtual channels, and tries to 1651 * allocate space in the link for them. For 0->slots transitions, 1652 * this step writes the remote VC payload commands. For slots->0 1653 * this just resets some internal state. 1654 */ 1655 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr) 1656 { 1657 struct drm_dp_mst_port *port; 1658 int i; 1659 int ret; 1660 mutex_lock(&mgr->payload_lock); 1661 for (i = 0; i < mgr->max_payloads; i++) { 1662 1663 if (!mgr->proposed_vcpis[i]) 1664 continue; 1665 1666 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1667 1668 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state); 1669 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) { 1670 ret = drm_dp_create_payload_step2(mgr, port, i + 1, &mgr->payloads[i]); 1671 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { 1672 ret = drm_dp_destroy_payload_step2(mgr, i + 1, &mgr->payloads[i]); 1673 } 1674 if (ret) { 1675 mutex_unlock(&mgr->payload_lock); 1676 return ret; 1677 } 1678 } 1679 mutex_unlock(&mgr->payload_lock); 1680 return 0; 1681 } 1682 EXPORT_SYMBOL(drm_dp_update_payload_part2); 1683 1684 #if 0 /* unused as of yet */ 1685 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, 1686 struct drm_dp_mst_port *port, 1687 int offset, int size) 1688 { 1689 int len; 1690 struct drm_dp_sideband_msg_tx *txmsg; 1691 1692 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1693 if (!txmsg) 1694 return -ENOMEM; 1695 1696 len = build_dpcd_read(txmsg, port->port_num, 0, 8); 1697 txmsg->dst = port->parent; 1698 1699 drm_dp_queue_down_tx(mgr, txmsg); 1700 1701 return 0; 1702 } 1703 #endif 1704 1705 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, 1706 struct drm_dp_mst_port *port, 1707 int offset, int size, u8 *bytes) 1708 { 1709 int len; 1710 int ret; 1711 struct drm_dp_sideband_msg_tx *txmsg; 1712 struct drm_dp_mst_branch *mstb; 1713 1714 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1715 if (!mstb) 1716 return -EINVAL; 1717 1718 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1719 if (!txmsg) { 1720 ret = -ENOMEM; 1721 goto fail_put; 1722 } 1723 1724 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes); 1725 txmsg->dst = mstb; 1726 1727 drm_dp_queue_down_tx(mgr, txmsg); 1728 1729 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1730 if (ret > 0) { 1731 if (txmsg->reply.reply_type == 1) { 1732 ret = -EINVAL; 1733 } else 1734 ret = 0; 1735 } 1736 kfree(txmsg); 1737 fail_put: 1738 drm_dp_put_mst_branch_device(mstb); 1739 return ret; 1740 } 1741 1742 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type) 1743 { 1744 struct drm_dp_sideband_msg_reply_body reply; 1745 1746 reply.reply_type = 1; 1747 reply.req_type = req_type; 1748 drm_dp_encode_sideband_reply(&reply, msg); 1749 return 0; 1750 } 1751 1752 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr, 1753 struct drm_dp_mst_branch *mstb, 1754 int req_type, int seqno, bool broadcast) 1755 { 1756 struct drm_dp_sideband_msg_tx *txmsg; 1757 1758 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1759 if (!txmsg) 1760 return -ENOMEM; 1761 1762 txmsg->dst = mstb; 1763 txmsg->seqno = seqno; 1764 drm_dp_encode_up_ack_reply(txmsg, req_type); 1765 1766 mutex_lock(&mgr->qlock); 1767 list_add_tail(&txmsg->next, &mgr->tx_msg_upq); 1768 if (!mgr->tx_up_in_progress) { 1769 process_single_up_tx_qlock(mgr); 1770 } 1771 mutex_unlock(&mgr->qlock); 1772 return 0; 1773 } 1774 1775 static bool drm_dp_get_vc_payload_bw(int dp_link_bw, 1776 int dp_link_count, 1777 int *out) 1778 { 1779 switch (dp_link_bw) { 1780 default: 1781 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n", 1782 dp_link_bw, dp_link_count); 1783 return false; 1784 1785 case DP_LINK_BW_1_62: 1786 *out = 3 * dp_link_count; 1787 break; 1788 case DP_LINK_BW_2_7: 1789 *out = 5 * dp_link_count; 1790 break; 1791 case DP_LINK_BW_5_4: 1792 *out = 10 * dp_link_count; 1793 break; 1794 } 1795 return true; 1796 } 1797 1798 /** 1799 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager 1800 * @mgr: manager to set state for 1801 * @mst_state: true to enable MST on this connector - false to disable. 1802 * 1803 * This is called by the driver when it detects an MST capable device plugged 1804 * into a DP MST capable port, or when a DP MST capable device is unplugged. 1805 */ 1806 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state) 1807 { 1808 int ret = 0; 1809 struct drm_dp_mst_branch *mstb = NULL; 1810 1811 mutex_lock(&mgr->lock); 1812 if (mst_state == mgr->mst_state) 1813 goto out_unlock; 1814 1815 mgr->mst_state = mst_state; 1816 /* set the device into MST mode */ 1817 if (mst_state) { 1818 WARN_ON(mgr->mst_primary); 1819 1820 /* get dpcd info */ 1821 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 1822 if (ret != DP_RECEIVER_CAP_SIZE) { 1823 DRM_DEBUG_KMS("failed to read DPCD\n"); 1824 goto out_unlock; 1825 } 1826 1827 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1], 1828 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK, 1829 &mgr->pbn_div)) { 1830 ret = -EINVAL; 1831 goto out_unlock; 1832 } 1833 1834 mgr->total_pbn = 2560; 1835 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div); 1836 mgr->avail_slots = mgr->total_slots; 1837 1838 /* add initial branch device at LCT 1 */ 1839 mstb = drm_dp_add_mst_branch_device(1, NULL); 1840 if (mstb == NULL) { 1841 ret = -ENOMEM; 1842 goto out_unlock; 1843 } 1844 mstb->mgr = mgr; 1845 1846 /* give this the main reference */ 1847 mgr->mst_primary = mstb; 1848 kref_get(&mgr->mst_primary->kref); 1849 1850 { 1851 struct drm_dp_payload reset_pay; 1852 reset_pay.start_slot = 0; 1853 reset_pay.num_slots = 0x3f; 1854 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay); 1855 } 1856 1857 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 1858 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 1859 if (ret < 0) { 1860 goto out_unlock; 1861 } 1862 1863 1864 /* sort out guid */ 1865 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16); 1866 if (ret != 16) { 1867 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret); 1868 goto out_unlock; 1869 } 1870 1871 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid); 1872 if (!mgr->guid_valid) { 1873 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16); 1874 mgr->guid_valid = true; 1875 } 1876 1877 queue_work(system_long_wq, &mgr->work); 1878 1879 ret = 0; 1880 } else { 1881 /* disable MST on the device */ 1882 mstb = mgr->mst_primary; 1883 mgr->mst_primary = NULL; 1884 /* this can fail if the device is gone */ 1885 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0); 1886 ret = 0; 1887 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload)); 1888 mgr->payload_mask = 0; 1889 set_bit(0, &mgr->payload_mask); 1890 } 1891 1892 out_unlock: 1893 mutex_unlock(&mgr->lock); 1894 if (mstb) 1895 drm_dp_put_mst_branch_device(mstb); 1896 return ret; 1897 1898 } 1899 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst); 1900 1901 /** 1902 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager 1903 * @mgr: manager to suspend 1904 * 1905 * This function tells the MST device that we can't handle UP messages 1906 * anymore. This should stop it from sending any since we are suspended. 1907 */ 1908 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr) 1909 { 1910 mutex_lock(&mgr->lock); 1911 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 1912 DP_MST_EN | DP_UPSTREAM_IS_SRC); 1913 mutex_unlock(&mgr->lock); 1914 } 1915 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend); 1916 1917 /** 1918 * drm_dp_mst_topology_mgr_resume() - resume the MST manager 1919 * @mgr: manager to resume 1920 * 1921 * This will fetch DPCD and see if the device is still there, 1922 * if it is, it will rewrite the MSTM control bits, and return. 1923 * 1924 * if the device fails this returns -1, and the driver should do 1925 * a full MST reprobe, in case we were undocked. 1926 */ 1927 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr) 1928 { 1929 int ret = 0; 1930 1931 mutex_lock(&mgr->lock); 1932 1933 if (mgr->mst_primary) { 1934 int sret; 1935 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 1936 if (sret != DP_RECEIVER_CAP_SIZE) { 1937 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); 1938 ret = -1; 1939 goto out_unlock; 1940 } 1941 1942 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 1943 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 1944 if (ret < 0) { 1945 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n"); 1946 ret = -1; 1947 goto out_unlock; 1948 } 1949 ret = 0; 1950 } else 1951 ret = -1; 1952 1953 out_unlock: 1954 mutex_unlock(&mgr->lock); 1955 return ret; 1956 } 1957 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume); 1958 1959 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up) 1960 { 1961 int len; 1962 u8 replyblock[32]; 1963 int replylen, origlen, curreply; 1964 int ret; 1965 struct drm_dp_sideband_msg_rx *msg; 1966 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE; 1967 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv; 1968 1969 len = min(mgr->max_dpcd_transaction_bytes, 16); 1970 ret = drm_dp_dpcd_read(mgr->aux, basereg, 1971 replyblock, len); 1972 if (ret != len) { 1973 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret); 1974 return; 1975 } 1976 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true); 1977 if (!ret) { 1978 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]); 1979 return; 1980 } 1981 replylen = msg->curchunk_len + msg->curchunk_hdrlen; 1982 1983 origlen = replylen; 1984 replylen -= len; 1985 curreply = len; 1986 while (replylen > 0) { 1987 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16); 1988 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply, 1989 replyblock, len); 1990 if (ret != len) { 1991 DRM_DEBUG_KMS("failed to read a chunk\n"); 1992 } 1993 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false); 1994 if (ret == false) 1995 DRM_DEBUG_KMS("failed to build sideband msg\n"); 1996 curreply += len; 1997 replylen -= len; 1998 } 1999 } 2000 2001 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) 2002 { 2003 int ret = 0; 2004 2005 drm_dp_get_one_sb_msg(mgr, false); 2006 2007 if (mgr->down_rep_recv.have_eomt) { 2008 struct drm_dp_sideband_msg_tx *txmsg; 2009 struct drm_dp_mst_branch *mstb; 2010 int slot = -1; 2011 mstb = drm_dp_get_mst_branch_device(mgr, 2012 mgr->down_rep_recv.initial_hdr.lct, 2013 mgr->down_rep_recv.initial_hdr.rad); 2014 2015 if (!mstb) { 2016 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct); 2017 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2018 return 0; 2019 } 2020 2021 /* find the message */ 2022 slot = mgr->down_rep_recv.initial_hdr.seqno; 2023 mutex_lock(&mgr->qlock); 2024 txmsg = mstb->tx_slots[slot]; 2025 /* remove from slots */ 2026 mutex_unlock(&mgr->qlock); 2027 2028 if (!txmsg) { 2029 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n", 2030 mstb, 2031 mgr->down_rep_recv.initial_hdr.seqno, 2032 mgr->down_rep_recv.initial_hdr.lct, 2033 mgr->down_rep_recv.initial_hdr.rad[0], 2034 mgr->down_rep_recv.msg[0]); 2035 drm_dp_put_mst_branch_device(mstb); 2036 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2037 return 0; 2038 } 2039 2040 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply); 2041 if (txmsg->reply.reply_type == 1) { 2042 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); 2043 } 2044 2045 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2046 drm_dp_put_mst_branch_device(mstb); 2047 2048 mutex_lock(&mgr->qlock); 2049 txmsg->state = DRM_DP_SIDEBAND_TX_RX; 2050 mstb->tx_slots[slot] = NULL; 2051 mutex_unlock(&mgr->qlock); 2052 2053 wake_up(&mgr->tx_waitq); 2054 } 2055 return ret; 2056 } 2057 2058 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr) 2059 { 2060 int ret = 0; 2061 drm_dp_get_one_sb_msg(mgr, true); 2062 2063 if (mgr->up_req_recv.have_eomt) { 2064 struct drm_dp_sideband_msg_req_body msg; 2065 struct drm_dp_mst_branch *mstb; 2066 bool seqno; 2067 mstb = drm_dp_get_mst_branch_device(mgr, 2068 mgr->up_req_recv.initial_hdr.lct, 2069 mgr->up_req_recv.initial_hdr.rad); 2070 if (!mstb) { 2071 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2072 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2073 return 0; 2074 } 2075 2076 seqno = mgr->up_req_recv.initial_hdr.seqno; 2077 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg); 2078 2079 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) { 2080 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false); 2081 drm_dp_update_port(mstb, &msg.u.conn_stat); 2082 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); 2083 (*mgr->cbs->hotplug)(mgr); 2084 2085 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) { 2086 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false); 2087 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn); 2088 } 2089 2090 drm_dp_put_mst_branch_device(mstb); 2091 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2092 } 2093 return ret; 2094 } 2095 2096 /** 2097 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify 2098 * @mgr: manager to notify irq for. 2099 * @esi: 4 bytes from SINK_COUNT_ESI 2100 * 2101 * This should be called from the driver when it detects a short IRQ, 2102 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The 2103 * topology manager will process the sideband messages received as a result 2104 * of this. 2105 */ 2106 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled) 2107 { 2108 int ret = 0; 2109 int sc; 2110 *handled = false; 2111 sc = esi[0] & 0x3f; 2112 2113 if (sc != mgr->sink_count) { 2114 mgr->sink_count = sc; 2115 *handled = true; 2116 } 2117 2118 if (esi[1] & DP_DOWN_REP_MSG_RDY) { 2119 ret = drm_dp_mst_handle_down_rep(mgr); 2120 *handled = true; 2121 } 2122 2123 if (esi[1] & DP_UP_REQ_MSG_RDY) { 2124 ret |= drm_dp_mst_handle_up_req(mgr); 2125 *handled = true; 2126 } 2127 2128 drm_dp_mst_kick_tx(mgr); 2129 return ret; 2130 } 2131 EXPORT_SYMBOL(drm_dp_mst_hpd_irq); 2132 2133 /** 2134 * drm_dp_mst_detect_port() - get connection status for an MST port 2135 * @mgr: manager for this port 2136 * @port: unverified pointer to a port 2137 * 2138 * This returns the current connection state for a port. It validates the 2139 * port pointer still exists so the caller doesn't require a reference 2140 */ 2141 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector, 2142 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2143 { 2144 enum drm_connector_status status = connector_status_disconnected; 2145 2146 /* we need to search for the port in the mgr in case its gone */ 2147 port = drm_dp_get_validated_port_ref(mgr, port); 2148 if (!port) 2149 return connector_status_disconnected; 2150 2151 if (!port->ddps) 2152 goto out; 2153 2154 switch (port->pdt) { 2155 case DP_PEER_DEVICE_NONE: 2156 case DP_PEER_DEVICE_MST_BRANCHING: 2157 break; 2158 2159 case DP_PEER_DEVICE_SST_SINK: 2160 status = connector_status_connected; 2161 /* for logical ports - cache the EDID */ 2162 if (port->port_num >= 8 && !port->cached_edid) { 2163 port->cached_edid = drm_get_edid(connector, &port->aux.ddc); 2164 } 2165 break; 2166 case DP_PEER_DEVICE_DP_LEGACY_CONV: 2167 if (port->ldps) 2168 status = connector_status_connected; 2169 break; 2170 } 2171 out: 2172 drm_dp_put_port(port); 2173 return status; 2174 } 2175 EXPORT_SYMBOL(drm_dp_mst_detect_port); 2176 2177 /** 2178 * drm_dp_mst_get_edid() - get EDID for an MST port 2179 * @connector: toplevel connector to get EDID for 2180 * @mgr: manager for this port 2181 * @port: unverified pointer to a port. 2182 * 2183 * This returns an EDID for the port connected to a connector, 2184 * It validates the pointer still exists so the caller doesn't require a 2185 * reference. 2186 */ 2187 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2188 { 2189 struct edid *edid = NULL; 2190 2191 /* we need to search for the port in the mgr in case its gone */ 2192 port = drm_dp_get_validated_port_ref(mgr, port); 2193 if (!port) 2194 return NULL; 2195 2196 if (port->cached_edid) 2197 edid = drm_edid_duplicate(port->cached_edid); 2198 else 2199 edid = drm_get_edid(connector, &port->aux.ddc); 2200 2201 drm_mode_connector_set_tile_property(connector); 2202 drm_dp_put_port(port); 2203 return edid; 2204 } 2205 EXPORT_SYMBOL(drm_dp_mst_get_edid); 2206 2207 /** 2208 * drm_dp_find_vcpi_slots() - find slots for this PBN value 2209 * @mgr: manager to use 2210 * @pbn: payload bandwidth to convert into slots. 2211 */ 2212 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, 2213 int pbn) 2214 { 2215 int num_slots; 2216 2217 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2218 2219 if (num_slots > mgr->avail_slots) 2220 return -ENOSPC; 2221 return num_slots; 2222 } 2223 EXPORT_SYMBOL(drm_dp_find_vcpi_slots); 2224 2225 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr, 2226 struct drm_dp_vcpi *vcpi, int pbn) 2227 { 2228 int num_slots; 2229 int ret; 2230 2231 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2232 2233 if (num_slots > mgr->avail_slots) 2234 return -ENOSPC; 2235 2236 vcpi->pbn = pbn; 2237 vcpi->aligned_pbn = num_slots * mgr->pbn_div; 2238 vcpi->num_slots = num_slots; 2239 2240 ret = drm_dp_mst_assign_payload_id(mgr, vcpi); 2241 if (ret < 0) 2242 return ret; 2243 return 0; 2244 } 2245 2246 /** 2247 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel 2248 * @mgr: manager for this port 2249 * @port: port to allocate a virtual channel for. 2250 * @pbn: payload bandwidth number to request 2251 * @slots: returned number of slots for this PBN. 2252 */ 2253 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots) 2254 { 2255 int ret; 2256 2257 port = drm_dp_get_validated_port_ref(mgr, port); 2258 if (!port) 2259 return false; 2260 2261 if (port->vcpi.vcpi > 0) { 2262 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn); 2263 if (pbn == port->vcpi.pbn) { 2264 *slots = port->vcpi.num_slots; 2265 return true; 2266 } 2267 } 2268 2269 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn); 2270 if (ret) { 2271 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret); 2272 goto out; 2273 } 2274 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots); 2275 *slots = port->vcpi.num_slots; 2276 2277 drm_dp_put_port(port); 2278 return true; 2279 out: 2280 return false; 2281 } 2282 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi); 2283 2284 /** 2285 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI 2286 * @mgr: manager for this port 2287 * @port: unverified pointer to a port. 2288 * 2289 * This just resets the number of slots for the ports VCPI for later programming. 2290 */ 2291 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2292 { 2293 port = drm_dp_get_validated_port_ref(mgr, port); 2294 if (!port) 2295 return; 2296 port->vcpi.num_slots = 0; 2297 drm_dp_put_port(port); 2298 } 2299 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots); 2300 2301 /** 2302 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI 2303 * @mgr: manager for this port 2304 * @port: unverified port to deallocate vcpi for 2305 */ 2306 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2307 { 2308 port = drm_dp_get_validated_port_ref(mgr, port); 2309 if (!port) 2310 return; 2311 2312 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 2313 port->vcpi.num_slots = 0; 2314 port->vcpi.pbn = 0; 2315 port->vcpi.aligned_pbn = 0; 2316 port->vcpi.vcpi = 0; 2317 drm_dp_put_port(port); 2318 } 2319 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi); 2320 2321 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, 2322 int id, struct drm_dp_payload *payload) 2323 { 2324 u8 payload_alloc[3], status; 2325 int ret; 2326 int retries = 0; 2327 2328 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, 2329 DP_PAYLOAD_TABLE_UPDATED); 2330 2331 payload_alloc[0] = id; 2332 payload_alloc[1] = payload->start_slot; 2333 payload_alloc[2] = payload->num_slots; 2334 2335 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3); 2336 if (ret != 3) { 2337 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret); 2338 goto fail; 2339 } 2340 2341 retry: 2342 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2343 if (ret < 0) { 2344 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2345 goto fail; 2346 } 2347 2348 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) { 2349 retries++; 2350 if (retries < 20) { 2351 usleep_range(10000, 20000); 2352 goto retry; 2353 } 2354 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status); 2355 ret = -EINVAL; 2356 goto fail; 2357 } 2358 ret = 0; 2359 fail: 2360 return ret; 2361 } 2362 2363 2364 /** 2365 * drm_dp_check_act_status() - Check ACT handled status. 2366 * @mgr: manager to use 2367 * 2368 * Check the payload status bits in the DPCD for ACT handled completion. 2369 */ 2370 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr) 2371 { 2372 u8 status; 2373 int ret; 2374 int count = 0; 2375 2376 do { 2377 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2378 2379 if (ret < 0) { 2380 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2381 goto fail; 2382 } 2383 2384 if (status & DP_PAYLOAD_ACT_HANDLED) 2385 break; 2386 count++; 2387 udelay(100); 2388 2389 } while (count < 30); 2390 2391 if (!(status & DP_PAYLOAD_ACT_HANDLED)) { 2392 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count); 2393 ret = -EINVAL; 2394 goto fail; 2395 } 2396 return 0; 2397 fail: 2398 return ret; 2399 } 2400 EXPORT_SYMBOL(drm_dp_check_act_status); 2401 2402 /** 2403 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode. 2404 * @clock: dot clock for the mode 2405 * @bpp: bpp for the mode. 2406 * 2407 * This uses the formula in the spec to calculate the PBN value for a mode. 2408 */ 2409 int drm_dp_calc_pbn_mode(int clock, int bpp) 2410 { 2411 fixed20_12 pix_bw; 2412 fixed20_12 fbpp; 2413 fixed20_12 result; 2414 fixed20_12 margin, tmp; 2415 u32 res; 2416 2417 pix_bw.full = dfixed_const(clock); 2418 fbpp.full = dfixed_const(bpp); 2419 tmp.full = dfixed_const(8); 2420 fbpp.full = dfixed_div(fbpp, tmp); 2421 2422 result.full = dfixed_mul(pix_bw, fbpp); 2423 margin.full = dfixed_const(54); 2424 tmp.full = dfixed_const(64); 2425 margin.full = dfixed_div(margin, tmp); 2426 result.full = dfixed_div(result, margin); 2427 2428 margin.full = dfixed_const(1006); 2429 tmp.full = dfixed_const(1000); 2430 margin.full = dfixed_div(margin, tmp); 2431 result.full = dfixed_mul(result, margin); 2432 2433 result.full = dfixed_div(result, tmp); 2434 result.full = dfixed_ceil(result); 2435 res = dfixed_trunc(result); 2436 return res; 2437 } 2438 EXPORT_SYMBOL(drm_dp_calc_pbn_mode); 2439 2440 static int test_calc_pbn_mode(void) 2441 { 2442 int ret; 2443 ret = drm_dp_calc_pbn_mode(154000, 30); 2444 if (ret != 689) 2445 return -EINVAL; 2446 ret = drm_dp_calc_pbn_mode(234000, 30); 2447 if (ret != 1047) 2448 return -EINVAL; 2449 return 0; 2450 } 2451 2452 /* we want to kick the TX after we've ack the up/down IRQs. */ 2453 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr) 2454 { 2455 queue_work(system_long_wq, &mgr->tx_work); 2456 } 2457 2458 static void drm_dp_mst_dump_mstb(struct seq_file *m, 2459 struct drm_dp_mst_branch *mstb) 2460 { 2461 struct drm_dp_mst_port *port; 2462 int tabs = mstb->lct; 2463 char prefix[10]; 2464 int i; 2465 2466 for (i = 0; i < tabs; i++) 2467 prefix[i] = '\t'; 2468 prefix[i] = '\0'; 2469 2470 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports); 2471 list_for_each_entry(port, &mstb->ports, next) { 2472 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector); 2473 if (port->mstb) 2474 drm_dp_mst_dump_mstb(m, port->mstb); 2475 } 2476 } 2477 2478 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 2479 char *buf) 2480 { 2481 int ret; 2482 int i; 2483 for (i = 0; i < 4; i++) { 2484 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16); 2485 if (ret != 16) 2486 break; 2487 } 2488 if (i == 4) 2489 return true; 2490 return false; 2491 } 2492 2493 /** 2494 * drm_dp_mst_dump_topology(): dump topology to seq file. 2495 * @m: seq_file to dump output to 2496 * @mgr: manager to dump current topology for. 2497 * 2498 * helper to dump MST topology to a seq file for debugfs. 2499 */ 2500 void drm_dp_mst_dump_topology(struct seq_file *m, 2501 struct drm_dp_mst_topology_mgr *mgr) 2502 { 2503 int i; 2504 struct drm_dp_mst_port *port; 2505 mutex_lock(&mgr->lock); 2506 if (mgr->mst_primary) 2507 drm_dp_mst_dump_mstb(m, mgr->mst_primary); 2508 2509 /* dump VCPIs */ 2510 mutex_unlock(&mgr->lock); 2511 2512 mutex_lock(&mgr->payload_lock); 2513 seq_printf(m, "vcpi: %lx\n", mgr->payload_mask); 2514 2515 for (i = 0; i < mgr->max_payloads; i++) { 2516 if (mgr->proposed_vcpis[i]) { 2517 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 2518 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots); 2519 } else 2520 seq_printf(m, "vcpi %d:unsed\n", i); 2521 } 2522 for (i = 0; i < mgr->max_payloads; i++) { 2523 seq_printf(m, "payload %d: %d, %d, %d\n", 2524 i, 2525 mgr->payloads[i].payload_state, 2526 mgr->payloads[i].start_slot, 2527 mgr->payloads[i].num_slots); 2528 2529 2530 } 2531 mutex_unlock(&mgr->payload_lock); 2532 2533 mutex_lock(&mgr->lock); 2534 if (mgr->mst_primary) { 2535 u8 buf[64]; 2536 bool bret; 2537 int ret; 2538 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE); 2539 seq_printf(m, "dpcd: "); 2540 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++) 2541 seq_printf(m, "%02x ", buf[i]); 2542 seq_printf(m, "\n"); 2543 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2); 2544 seq_printf(m, "faux/mst: "); 2545 for (i = 0; i < 2; i++) 2546 seq_printf(m, "%02x ", buf[i]); 2547 seq_printf(m, "\n"); 2548 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1); 2549 seq_printf(m, "mst ctrl: "); 2550 for (i = 0; i < 1; i++) 2551 seq_printf(m, "%02x ", buf[i]); 2552 seq_printf(m, "\n"); 2553 2554 bret = dump_dp_payload_table(mgr, buf); 2555 if (bret == true) { 2556 seq_printf(m, "payload table: "); 2557 for (i = 0; i < 63; i++) 2558 seq_printf(m, "%02x ", buf[i]); 2559 seq_printf(m, "\n"); 2560 } 2561 2562 } 2563 2564 mutex_unlock(&mgr->lock); 2565 2566 } 2567 EXPORT_SYMBOL(drm_dp_mst_dump_topology); 2568 2569 static void drm_dp_tx_work(struct work_struct *work) 2570 { 2571 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work); 2572 2573 mutex_lock(&mgr->qlock); 2574 if (mgr->tx_down_in_progress) 2575 process_single_down_tx_qlock(mgr); 2576 mutex_unlock(&mgr->qlock); 2577 } 2578 2579 /** 2580 * drm_dp_mst_topology_mgr_init - initialise a topology manager 2581 * @mgr: manager struct to initialise 2582 * @dev: device providing this structure - for i2c addition. 2583 * @aux: DP helper aux channel to talk to this device 2584 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit 2585 * @max_payloads: maximum number of payloads this GPU can source 2586 * @conn_base_id: the connector object ID the MST device is connected to. 2587 * 2588 * Return 0 for success, or negative error code on failure 2589 */ 2590 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, 2591 struct device *dev, struct drm_dp_aux *aux, 2592 int max_dpcd_transaction_bytes, 2593 int max_payloads, int conn_base_id) 2594 { 2595 mutex_init(&mgr->lock); 2596 mutex_init(&mgr->qlock); 2597 mutex_init(&mgr->payload_lock); 2598 INIT_LIST_HEAD(&mgr->tx_msg_upq); 2599 INIT_LIST_HEAD(&mgr->tx_msg_downq); 2600 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); 2601 INIT_WORK(&mgr->tx_work, drm_dp_tx_work); 2602 init_waitqueue_head(&mgr->tx_waitq); 2603 mgr->dev = dev; 2604 mgr->aux = aux; 2605 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes; 2606 mgr->max_payloads = max_payloads; 2607 mgr->conn_base_id = conn_base_id; 2608 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL); 2609 if (!mgr->payloads) 2610 return -ENOMEM; 2611 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL); 2612 if (!mgr->proposed_vcpis) 2613 return -ENOMEM; 2614 set_bit(0, &mgr->payload_mask); 2615 test_calc_pbn_mode(); 2616 return 0; 2617 } 2618 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init); 2619 2620 /** 2621 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager. 2622 * @mgr: manager to destroy 2623 */ 2624 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) 2625 { 2626 mutex_lock(&mgr->payload_lock); 2627 kfree(mgr->payloads); 2628 mgr->payloads = NULL; 2629 kfree(mgr->proposed_vcpis); 2630 mgr->proposed_vcpis = NULL; 2631 mutex_unlock(&mgr->payload_lock); 2632 mgr->dev = NULL; 2633 mgr->aux = NULL; 2634 } 2635 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy); 2636 2637 /* I2C device */ 2638 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 2639 int num) 2640 { 2641 struct drm_dp_aux *aux = adapter->algo_data; 2642 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux); 2643 struct drm_dp_mst_branch *mstb; 2644 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 2645 unsigned int i; 2646 bool reading = false; 2647 struct drm_dp_sideband_msg_req_body msg; 2648 struct drm_dp_sideband_msg_tx *txmsg = NULL; 2649 int ret; 2650 2651 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 2652 if (!mstb) 2653 return -EREMOTEIO; 2654 2655 /* construct i2c msg */ 2656 /* see if last msg is a read */ 2657 if (msgs[num - 1].flags & I2C_M_RD) 2658 reading = true; 2659 2660 if (!reading) { 2661 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n"); 2662 ret = -EIO; 2663 goto out; 2664 } 2665 2666 msg.req_type = DP_REMOTE_I2C_READ; 2667 msg.u.i2c_read.num_transactions = num - 1; 2668 msg.u.i2c_read.port_number = port->port_num; 2669 for (i = 0; i < num - 1; i++) { 2670 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr; 2671 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len; 2672 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf; 2673 } 2674 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr; 2675 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len; 2676 2677 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 2678 if (!txmsg) { 2679 ret = -ENOMEM; 2680 goto out; 2681 } 2682 2683 txmsg->dst = mstb; 2684 drm_dp_encode_sideband_req(&msg, txmsg); 2685 2686 drm_dp_queue_down_tx(mgr, txmsg); 2687 2688 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 2689 if (ret > 0) { 2690 2691 if (txmsg->reply.reply_type == 1) { /* got a NAK back */ 2692 ret = -EREMOTEIO; 2693 goto out; 2694 } 2695 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) { 2696 ret = -EIO; 2697 goto out; 2698 } 2699 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len); 2700 ret = num; 2701 } 2702 out: 2703 kfree(txmsg); 2704 drm_dp_put_mst_branch_device(mstb); 2705 return ret; 2706 } 2707 2708 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter) 2709 { 2710 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | 2711 I2C_FUNC_SMBUS_READ_BLOCK_DATA | 2712 I2C_FUNC_SMBUS_BLOCK_PROC_CALL | 2713 I2C_FUNC_10BIT_ADDR; 2714 } 2715 2716 static const struct i2c_algorithm drm_dp_mst_i2c_algo = { 2717 .functionality = drm_dp_mst_i2c_functionality, 2718 .master_xfer = drm_dp_mst_i2c_xfer, 2719 }; 2720 2721 /** 2722 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX 2723 * @aux: DisplayPort AUX channel 2724 * 2725 * Returns 0 on success or a negative error code on failure. 2726 */ 2727 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux) 2728 { 2729 aux->ddc.algo = &drm_dp_mst_i2c_algo; 2730 aux->ddc.algo_data = aux; 2731 aux->ddc.retries = 3; 2732 2733 aux->ddc.class = I2C_CLASS_DDC; 2734 aux->ddc.owner = THIS_MODULE; 2735 aux->ddc.dev.parent = aux->dev; 2736 aux->ddc.dev.of_node = aux->dev->of_node; 2737 2738 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev), 2739 sizeof(aux->ddc.name)); 2740 2741 return i2c_add_adapter(&aux->ddc); 2742 } 2743 2744 /** 2745 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter 2746 * @aux: DisplayPort AUX channel 2747 */ 2748 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux) 2749 { 2750 i2c_del_adapter(&aux->ddc); 2751 } 2752