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