2 * Copyright © 2014 Red Hat
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.
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
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>
33 #include <drm/drm_fixed.h>
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.
42 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
44 static int test_calc_pbn_mode(void);
46 static void drm_dp_put_port(struct drm_dp_mst_port *port);
48 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
50 struct drm_dp_payload *payload);
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);
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,
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)
73 int number_of_bits = num_nibbles * 4;
76 while (number_of_bits != 0) {
79 remainder |= (data[array_index] & bitmask) >> bitshift;
87 if ((remainder & 0x10) == 0x10)
92 while (number_of_bits != 0) {
95 if ((remainder & 0x10) != 0)
102 static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
107 int number_of_bits = number_of_bytes * 8;
110 while (number_of_bits != 0) {
113 remainder |= (data[array_index] & bitmask) >> bitshift;
121 if ((remainder & 0x100) == 0x100)
126 while (number_of_bits != 0) {
129 if ((remainder & 0x100) != 0)
133 return remainder & 0xff;
135 static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
138 size += (hdr->lct / 2);
142 static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
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);
155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
156 buf[idx - 1] |= (crc4 & 0xf);
161 static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
162 u8 *buf, int buflen, u8 *hdrlen)
171 len += ((buf[0] & 0xf0) >> 4) / 2;
174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
181 hdr->lct = (buf[0] & 0xf0) >> 4;
182 hdr->lcr = (buf[0] & 0xf);
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;
190 hdr->somt = (buf[idx] >> 7) & 0x1;
191 hdr->eomt = (buf[idx] >> 6) & 0x1;
192 hdr->seqno = (buf[idx] >> 4) & 0x1;
198 static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
199 struct drm_dp_sideband_msg_tx *raw)
204 buf[idx++] = req->req_type & 0x7f;
206 switch (req->req_type) {
207 case DP_ENUM_PATH_RESOURCES:
208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
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);
215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
217 buf[idx] = (req->u.allocate_payload.pbn >> 8);
219 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
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);
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;
232 case DP_QUERY_PAYLOAD:
233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
235 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
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;
242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
246 buf[idx] = (req->u.dpcd_read.num_bytes);
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;
254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
258 buf[idx] = (req->u.dpcd_write.num_bytes);
260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
261 idx += req->u.dpcd_write.num_bytes;
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);
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;
270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
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;
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);
279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
281 buf[idx] = (req->u.i2c_read.num_bytes_read);
285 case DP_REMOTE_I2C_WRITE:
286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
290 buf[idx] = (req->u.i2c_write.num_bytes);
292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
293 idx += req->u.i2c_write.num_bytes;
299 static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
302 crc4 = drm_dp_msg_data_crc4(msg, len);
306 static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
307 struct drm_dp_sideband_msg_tx *raw)
312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
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)
326 struct drm_dp_sideband_msg_hdr recv_hdr;
327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
333 /* get length contained in this portion */
334 msg->curchunk_len = recv_hdr.msg_len;
335 msg->curchunk_hdrlen = hdrlen;
337 /* we have already gotten an somt - don't bother parsing */
338 if (recv_hdr.somt && msg->have_somt)
342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
343 msg->have_somt = true;
346 msg->have_eomt = true;
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);
352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
353 msg->curchunk_idx += replybuflen;
356 if (msg->curchunk_idx >= msg->curchunk_len) {
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;
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)
371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
375 if (idx > raw->curlen)
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;
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);
385 if (idx > raw->curlen)
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;
392 if (idx > raw->curlen)
394 if (repmsg->u.link_addr.ports[i].input_port == 0) {
395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
397 if (idx > raw->curlen)
399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
401 if (idx > raw->curlen)
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);
408 if (idx > raw->curlen)
414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
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)
422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
424 if (idx > raw->curlen)
426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
427 if (idx > raw->curlen)
430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
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)
441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
443 if (idx > raw->curlen)
447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
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)
456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
458 if (idx > raw->curlen)
460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
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)
474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
476 if (idx > raw->curlen)
478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
480 if (idx > raw->curlen)
482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
484 if (idx > raw->curlen)
488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
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)
496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
498 if (idx > raw->curlen)
500 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
502 if (idx > raw->curlen)
504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
506 if (idx > raw->curlen)
510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
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)
518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
520 if (idx > raw->curlen)
522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
524 if (idx > raw->curlen)
528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
532 static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
533 struct drm_dp_sideband_msg_reply_body *msg)
535 memset(msg, 0, sizeof(*msg));
536 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
537 msg->req_type = (raw->msg[0] & 0x7f);
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];
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);
562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
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)
572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
574 if (idx > raw->curlen)
577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
579 if (idx > raw->curlen)
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);
590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
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)
599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
601 if (idx > raw->curlen)
604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
606 if (idx > raw->curlen)
609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
617 static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
618 struct drm_dp_sideband_msg_req_body *msg)
620 memset(msg, 0, sizeof(*msg));
621 msg->req_type = (raw->msg[0] & 0x7f);
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);
629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
634 static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
636 struct drm_dp_sideband_msg_req_body req;
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);
648 static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
650 struct drm_dp_sideband_msg_req_body req;
652 req.req_type = DP_LINK_ADDRESS;
653 drm_dp_encode_sideband_req(&req, msg);
657 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
659 struct drm_dp_sideband_msg_req_body req;
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;
668 static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
669 u8 vcpi, uint16_t pbn)
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;
682 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
683 struct drm_dp_vcpi *vcpi)
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) {
691 DRM_DEBUG_KMS("out of payload ids %d\n", ret);
695 set_bit(ret, &mgr->payload_mask);
697 mgr->proposed_vcpis[ret - 1] = vcpi;
699 mutex_unlock(&mgr->payload_lock);
703 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
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);
716 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
717 struct drm_dp_sideband_msg_tx *txmsg)
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);
727 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
728 struct drm_dp_sideband_msg_tx *txmsg)
730 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
733 ret = wait_event_timeout(mgr->tx_waitq,
734 check_txmsg_state(mgr, txmsg),
736 mutex_lock(&mstb->mgr->qlock);
738 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
743 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
745 /* dump some state */
749 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
750 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
751 list_del(&txmsg->next);
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;
760 mutex_unlock(&mgr->qlock);
765 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
767 struct drm_dp_mst_branch *mstb;
769 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
775 memcpy(mstb->rad, rad, lct / 2);
776 INIT_LIST_HEAD(&mstb->ports);
777 kref_init(&mstb->kref);
781 static void drm_dp_destroy_mst_branch_device(struct kref *kref)
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;
787 cancel_work_sync(&mstb->mgr->work);
790 * destroy all ports - don't need lock
791 * as there are no more references to the mst branch
792 * device at this point.
794 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
795 list_del(&port->next);
796 drm_dp_put_port(port);
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;
806 if (mstb->tx_slots[1]) {
807 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
808 mstb->tx_slots[1] = NULL;
811 mutex_unlock(&mstb->mgr->qlock);
814 wake_up(&mstb->mgr->tx_waitq);
818 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
820 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
824 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
826 struct drm_dp_mst_branch *mstb;
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);
834 case DP_PEER_DEVICE_MST_BRANCHING:
837 drm_dp_put_mst_branch_device(mstb);
842 static void drm_dp_destroy_port(struct kref *kref)
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;
847 port->vcpi.num_slots = 0;
849 kfree(port->cached_edid);
851 /* we can't destroy the connector here, as
852 we might be holding the mode_config.mutex
853 from an EDID retrieval */
854 if (port->connector) {
855 mutex_lock(&mgr->destroy_connector_lock);
856 list_add(&port->next, &mgr->destroy_connector_list);
857 mutex_unlock(&mgr->destroy_connector_lock);
858 schedule_work(&mgr->destroy_connector_work);
861 drm_dp_port_teardown_pdt(port, port->pdt);
863 if (!port->input && port->vcpi.vcpi > 0)
864 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
868 (*mgr->cbs->hotplug)(mgr);
871 static void drm_dp_put_port(struct drm_dp_mst_port *port)
873 kref_put(&port->kref, drm_dp_destroy_port);
876 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)
878 struct drm_dp_mst_port *port;
879 struct drm_dp_mst_branch *rmstb;
880 if (to_find == mstb) {
881 kref_get(&mstb->kref);
884 list_for_each_entry(port, &mstb->ports, next) {
886 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
894 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)
896 struct drm_dp_mst_branch *rmstb = NULL;
897 mutex_lock(&mgr->lock);
898 if (mgr->mst_primary)
899 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
900 mutex_unlock(&mgr->lock);
904 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)
906 struct drm_dp_mst_port *port, *mport;
908 list_for_each_entry(port, &mstb->ports, next) {
909 if (port == to_find) {
910 kref_get(&port->kref);
914 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
922 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)
924 struct drm_dp_mst_port *rport = NULL;
925 mutex_lock(&mgr->lock);
926 if (mgr->mst_primary)
927 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
928 mutex_unlock(&mgr->lock);
932 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
934 struct drm_dp_mst_port *port;
936 list_for_each_entry(port, &mstb->ports, next) {
937 if (port->port_num == port_num) {
938 kref_get(&port->kref);
947 * calculate a new RAD for this MST branch device
948 * if parent has an LCT of 2 then it has 1 nibble of RAD,
949 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
951 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
954 int lct = port->parent->lct;
958 memcpy(rad, port->parent->rad, idx);
959 shift = (lct % 2) ? 4 : 0;
963 rad[idx] |= port->port_num << shift;
968 * return sends link address for new mstb
970 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
974 bool send_link = false;
976 case DP_PEER_DEVICE_DP_LEGACY_CONV:
977 case DP_PEER_DEVICE_SST_SINK:
978 /* add i2c over sideband */
979 ret = drm_dp_mst_register_i2c_bus(&port->aux);
981 case DP_PEER_DEVICE_MST_BRANCHING:
982 lct = drm_dp_calculate_rad(port, rad);
984 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
985 port->mstb->mgr = port->mgr;
986 port->mstb->port_parent = port;
994 static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
995 struct drm_dp_mst_port *port)
998 if (port->dpcd_rev >= 0x12) {
999 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
1000 if (!port->guid_valid) {
1001 ret = drm_dp_send_dpcd_write(mstb->mgr,
1005 port->guid_valid = true;
1010 static void build_mst_prop_path(struct drm_dp_mst_port *port,
1011 struct drm_dp_mst_branch *mstb,
1013 size_t proppath_size)
1017 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
1018 for (i = 0; i < (mstb->lct - 1); i++) {
1019 int shift = (i % 2) ? 0 : 4;
1020 int port_num = mstb->rad[i / 2] >> shift;
1021 snprintf(temp, sizeof(temp), "-%d", port_num);
1022 strlcat(proppath, temp, proppath_size);
1024 snprintf(temp, sizeof(temp), "-%d", port->port_num);
1025 strlcat(proppath, temp, proppath_size);
1028 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1030 struct drm_dp_link_addr_reply_port *port_msg)
1032 struct drm_dp_mst_port *port;
1034 bool created = false;
1037 port = drm_dp_get_port(mstb, port_msg->port_number);
1039 port = kzalloc(sizeof(*port), GFP_KERNEL);
1042 kref_init(&port->kref);
1043 port->parent = mstb;
1044 port->port_num = port_msg->port_number;
1045 port->mgr = mstb->mgr;
1046 port->aux.name = "DPMST";
1047 port->aux.dev = dev;
1050 old_pdt = port->pdt;
1051 old_ddps = port->ddps;
1054 port->pdt = port_msg->peer_device_type;
1055 port->input = port_msg->input_port;
1056 port->mcs = port_msg->mcs;
1057 port->ddps = port_msg->ddps;
1058 port->ldps = port_msg->legacy_device_plug_status;
1059 port->dpcd_rev = port_msg->dpcd_revision;
1060 port->num_sdp_streams = port_msg->num_sdp_streams;
1061 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1062 memcpy(port->guid, port_msg->peer_guid, 16);
1064 /* manage mstb port lists with mgr lock - take a reference
1067 mutex_lock(&mstb->mgr->lock);
1068 kref_get(&port->kref);
1069 list_add(&port->next, &mstb->ports);
1070 mutex_unlock(&mstb->mgr->lock);
1073 if (old_ddps != port->ddps) {
1075 drm_dp_check_port_guid(mstb, port);
1077 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1079 port->guid_valid = false;
1080 port->available_pbn = 0;
1084 if (old_pdt != port->pdt && !port->input) {
1085 drm_dp_port_teardown_pdt(port, old_pdt);
1087 ret = drm_dp_port_setup_pdt(port);
1089 drm_dp_send_link_address(mstb->mgr, port->mstb);
1090 port->mstb->link_address_sent = true;
1094 if (created && !port->input) {
1096 build_mst_prop_path(port, mstb, proppath, sizeof(proppath));
1097 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1099 if (port->port_num >= 8) {
1100 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
1104 /* put reference to this port */
1105 drm_dp_put_port(port);
1108 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1109 struct drm_dp_connection_status_notify *conn_stat)
1111 struct drm_dp_mst_port *port;
1114 bool dowork = false;
1115 port = drm_dp_get_port(mstb, conn_stat->port_number);
1119 old_ddps = port->ddps;
1120 old_pdt = port->pdt;
1121 port->pdt = conn_stat->peer_device_type;
1122 port->mcs = conn_stat->message_capability_status;
1123 port->ldps = conn_stat->legacy_device_plug_status;
1124 port->ddps = conn_stat->displayport_device_plug_status;
1126 if (old_ddps != port->ddps) {
1128 drm_dp_check_port_guid(mstb, port);
1131 port->guid_valid = false;
1132 port->available_pbn = 0;
1135 if (old_pdt != port->pdt && !port->input) {
1136 drm_dp_port_teardown_pdt(port, old_pdt);
1138 if (drm_dp_port_setup_pdt(port))
1142 drm_dp_put_port(port);
1144 queue_work(system_long_wq, &mstb->mgr->work);
1148 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1151 struct drm_dp_mst_branch *mstb;
1152 struct drm_dp_mst_port *port;
1154 /* find the port by iterating down */
1156 mutex_lock(&mgr->lock);
1157 mstb = mgr->mst_primary;
1159 for (i = 0; i < lct - 1; i++) {
1160 int shift = (i % 2) ? 0 : 4;
1161 int port_num = rad[i / 2] >> shift;
1163 list_for_each_entry(port, &mstb->ports, next) {
1164 if (port->port_num == port_num) {
1166 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1175 kref_get(&mstb->kref);
1176 mutex_unlock(&mgr->lock);
1180 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1181 struct drm_dp_mst_branch *mstb)
1183 struct drm_dp_mst_port *port;
1184 struct drm_dp_mst_branch *mstb_child;
1185 if (!mstb->link_address_sent) {
1186 drm_dp_send_link_address(mgr, mstb);
1187 mstb->link_address_sent = true;
1189 list_for_each_entry(port, &mstb->ports, next) {
1196 if (!port->available_pbn)
1197 drm_dp_send_enum_path_resources(mgr, mstb, port);
1200 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
1202 drm_dp_check_and_send_link_address(mgr, mstb_child);
1203 drm_dp_put_mst_branch_device(mstb_child);
1209 static void drm_dp_mst_link_probe_work(struct work_struct *work)
1211 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1212 struct drm_dp_mst_branch *mstb;
1214 mutex_lock(&mgr->lock);
1215 mstb = mgr->mst_primary;
1217 kref_get(&mstb->kref);
1219 mutex_unlock(&mgr->lock);
1221 drm_dp_check_and_send_link_address(mgr, mstb);
1222 drm_dp_put_mst_branch_device(mstb);
1226 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1229 static u8 zero_guid[16];
1231 if (!memcmp(guid, zero_guid, 16)) {
1232 u64 salt = get_jiffies_64();
1233 memcpy(&guid[0], &salt, sizeof(u64));
1234 memcpy(&guid[8], &salt, sizeof(u64));
1241 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1243 struct drm_dp_sideband_msg_req_body req;
1245 req.req_type = DP_REMOTE_DPCD_READ;
1246 req.u.dpcd_read.port_number = port_num;
1247 req.u.dpcd_read.dpcd_address = offset;
1248 req.u.dpcd_read.num_bytes = num_bytes;
1249 drm_dp_encode_sideband_req(&req, msg);
1255 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1256 bool up, u8 *msg, int len)
1259 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1260 int tosend, total, offset;
1267 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1269 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1272 if (ret != tosend) {
1273 if (ret == -EIO && retries < 5) {
1277 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1283 } while (total > 0);
1287 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1288 struct drm_dp_sideband_msg_tx *txmsg)
1290 struct drm_dp_mst_branch *mstb = txmsg->dst;
1292 /* both msg slots are full */
1293 if (txmsg->seqno == -1) {
1294 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1295 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1298 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1299 txmsg->seqno = mstb->last_seqno;
1300 mstb->last_seqno ^= 1;
1301 } else if (mstb->tx_slots[0] == NULL)
1305 mstb->tx_slots[txmsg->seqno] = txmsg;
1308 hdr->path_msg = txmsg->path_msg;
1309 hdr->lct = mstb->lct;
1310 hdr->lcr = mstb->lct - 1;
1312 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1313 hdr->seqno = txmsg->seqno;
1317 * process a single block of the next message in the sideband queue
1319 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1320 struct drm_dp_sideband_msg_tx *txmsg,
1324 struct drm_dp_sideband_msg_hdr hdr;
1325 int len, space, idx, tosend;
1328 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1330 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1332 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1335 /* make hdr from dst mst - for replies use seqno
1336 otherwise assign one */
1337 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1341 /* amount left to send in this message */
1342 len = txmsg->cur_len - txmsg->cur_offset;
1344 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1345 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1347 tosend = min(len, space);
1348 if (len == txmsg->cur_len)
1354 hdr.msg_len = tosend + 1;
1355 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1356 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1357 /* add crc at end */
1358 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1361 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1363 DRM_DEBUG_KMS("sideband msg failed to send\n");
1367 txmsg->cur_offset += tosend;
1368 if (txmsg->cur_offset == txmsg->cur_len) {
1369 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1375 /* must be called holding qlock */
1376 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1378 struct drm_dp_sideband_msg_tx *txmsg;
1381 /* construct a chunk from the first msg in the tx_msg queue */
1382 if (list_empty(&mgr->tx_msg_downq)) {
1383 mgr->tx_down_in_progress = false;
1386 mgr->tx_down_in_progress = true;
1388 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1389 ret = process_single_tx_qlock(mgr, txmsg, false);
1391 /* txmsg is sent it should be in the slots now */
1392 list_del(&txmsg->next);
1394 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1395 list_del(&txmsg->next);
1396 if (txmsg->seqno != -1)
1397 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1398 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1399 wake_up(&mgr->tx_waitq);
1401 if (list_empty(&mgr->tx_msg_downq)) {
1402 mgr->tx_down_in_progress = false;
1407 /* called holding qlock */
1408 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1410 struct drm_dp_sideband_msg_tx *txmsg;
1413 /* construct a chunk from the first msg in the tx_msg queue */
1414 if (list_empty(&mgr->tx_msg_upq)) {
1415 mgr->tx_up_in_progress = false;
1419 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1420 ret = process_single_tx_qlock(mgr, txmsg, true);
1422 /* up txmsgs aren't put in slots - so free after we send it */
1423 list_del(&txmsg->next);
1426 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1427 mgr->tx_up_in_progress = true;
1430 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1431 struct drm_dp_sideband_msg_tx *txmsg)
1433 mutex_lock(&mgr->qlock);
1434 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1435 if (!mgr->tx_down_in_progress)
1436 process_single_down_tx_qlock(mgr);
1437 mutex_unlock(&mgr->qlock);
1440 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1441 struct drm_dp_mst_branch *mstb)
1444 struct drm_dp_sideband_msg_tx *txmsg;
1447 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1452 len = build_link_address(txmsg);
1454 drm_dp_queue_down_tx(mgr, txmsg);
1456 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1460 if (txmsg->reply.reply_type == 1)
1461 DRM_DEBUG_KMS("link address nak received\n");
1463 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1464 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1465 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,
1466 txmsg->reply.u.link_addr.ports[i].input_port,
1467 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1468 txmsg->reply.u.link_addr.ports[i].port_number,
1469 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1470 txmsg->reply.u.link_addr.ports[i].mcs,
1471 txmsg->reply.u.link_addr.ports[i].ddps,
1472 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1473 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1474 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1476 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1477 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1479 (*mgr->cbs->hotplug)(mgr);
1482 DRM_DEBUG_KMS("link address failed %d\n", ret);
1488 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1489 struct drm_dp_mst_branch *mstb,
1490 struct drm_dp_mst_port *port)
1493 struct drm_dp_sideband_msg_tx *txmsg;
1496 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1501 len = build_enum_path_resources(txmsg, port->port_num);
1503 drm_dp_queue_down_tx(mgr, txmsg);
1505 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1507 if (txmsg->reply.reply_type == 1)
1508 DRM_DEBUG_KMS("enum path resources nak received\n");
1510 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1511 DRM_ERROR("got incorrect port in response\n");
1512 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,
1513 txmsg->reply.u.path_resources.avail_payload_bw_number);
1514 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1522 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1523 struct drm_dp_mst_port *port,
1527 struct drm_dp_sideband_msg_tx *txmsg;
1528 struct drm_dp_mst_branch *mstb;
1531 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1535 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1542 len = build_allocate_payload(txmsg, port->port_num,
1546 drm_dp_queue_down_tx(mgr, txmsg);
1548 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1550 if (txmsg->reply.reply_type == 1) {
1557 drm_dp_put_mst_branch_device(mstb);
1561 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1563 struct drm_dp_payload *payload)
1567 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1569 payload->payload_state = 0;
1572 payload->payload_state = DP_PAYLOAD_LOCAL;
1576 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1577 struct drm_dp_mst_port *port,
1579 struct drm_dp_payload *payload)
1582 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1585 payload->payload_state = DP_PAYLOAD_REMOTE;
1589 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1590 struct drm_dp_mst_port *port,
1592 struct drm_dp_payload *payload)
1594 DRM_DEBUG_KMS("\n");
1595 /* its okay for these to fail */
1597 drm_dp_payload_send_msg(mgr, port, id, 0);
1600 drm_dp_dpcd_write_payload(mgr, id, payload);
1601 payload->payload_state = 0;
1605 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1607 struct drm_dp_payload *payload)
1609 payload->payload_state = 0;
1614 * drm_dp_update_payload_part1() - Execute payload update part 1
1615 * @mgr: manager to use.
1617 * This iterates over all proposed virtual channels, and tries to
1618 * allocate space in the link for them. For 0->slots transitions,
1619 * this step just writes the VCPI to the MST device. For slots->0
1620 * transitions, this writes the updated VCPIs and removes the
1621 * remote VC payloads.
1623 * after calling this the driver should generate ACT and payload
1626 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1630 struct drm_dp_payload req_payload;
1631 struct drm_dp_mst_port *port;
1633 mutex_lock(&mgr->payload_lock);
1634 for (i = 0; i < mgr->max_payloads; i++) {
1635 /* solve the current payloads - compare to the hw ones
1636 - update the hw view */
1637 req_payload.start_slot = cur_slots;
1638 if (mgr->proposed_vcpis[i]) {
1639 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1640 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1643 req_payload.num_slots = 0;
1645 /* work out what is required to happen with this payload */
1646 if (mgr->payloads[i].start_slot != req_payload.start_slot ||
1647 mgr->payloads[i].num_slots != req_payload.num_slots) {
1649 /* need to push an update for this payload */
1650 if (req_payload.num_slots) {
1651 drm_dp_create_payload_step1(mgr, i + 1, &req_payload);
1652 mgr->payloads[i].num_slots = req_payload.num_slots;
1653 } else if (mgr->payloads[i].num_slots) {
1654 mgr->payloads[i].num_slots = 0;
1655 drm_dp_destroy_payload_step1(mgr, port, i + 1, &mgr->payloads[i]);
1656 req_payload.payload_state = mgr->payloads[i].payload_state;
1658 req_payload.payload_state = 0;
1660 mgr->payloads[i].start_slot = req_payload.start_slot;
1661 mgr->payloads[i].payload_state = req_payload.payload_state;
1663 cur_slots += req_payload.num_slots;
1665 mutex_unlock(&mgr->payload_lock);
1669 EXPORT_SYMBOL(drm_dp_update_payload_part1);
1672 * drm_dp_update_payload_part2() - Execute payload update part 2
1673 * @mgr: manager to use.
1675 * This iterates over all proposed virtual channels, and tries to
1676 * allocate space in the link for them. For 0->slots transitions,
1677 * this step writes the remote VC payload commands. For slots->0
1678 * this just resets some internal state.
1680 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1682 struct drm_dp_mst_port *port;
1685 mutex_lock(&mgr->payload_lock);
1686 for (i = 0; i < mgr->max_payloads; i++) {
1688 if (!mgr->proposed_vcpis[i])
1691 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1693 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1694 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1695 ret = drm_dp_create_payload_step2(mgr, port, i + 1, &mgr->payloads[i]);
1696 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1697 ret = drm_dp_destroy_payload_step2(mgr, i + 1, &mgr->payloads[i]);
1700 mutex_unlock(&mgr->payload_lock);
1704 mutex_unlock(&mgr->payload_lock);
1707 EXPORT_SYMBOL(drm_dp_update_payload_part2);
1709 #if 0 /* unused as of yet */
1710 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1711 struct drm_dp_mst_port *port,
1712 int offset, int size)
1715 struct drm_dp_sideband_msg_tx *txmsg;
1717 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1721 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1722 txmsg->dst = port->parent;
1724 drm_dp_queue_down_tx(mgr, txmsg);
1730 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1731 struct drm_dp_mst_port *port,
1732 int offset, int size, u8 *bytes)
1736 struct drm_dp_sideband_msg_tx *txmsg;
1737 struct drm_dp_mst_branch *mstb;
1739 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1743 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1749 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1752 drm_dp_queue_down_tx(mgr, txmsg);
1754 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1756 if (txmsg->reply.reply_type == 1) {
1763 drm_dp_put_mst_branch_device(mstb);
1767 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1769 struct drm_dp_sideband_msg_reply_body reply;
1771 reply.reply_type = 1;
1772 reply.req_type = req_type;
1773 drm_dp_encode_sideband_reply(&reply, msg);
1777 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1778 struct drm_dp_mst_branch *mstb,
1779 int req_type, int seqno, bool broadcast)
1781 struct drm_dp_sideband_msg_tx *txmsg;
1783 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1788 txmsg->seqno = seqno;
1789 drm_dp_encode_up_ack_reply(txmsg, req_type);
1791 mutex_lock(&mgr->qlock);
1792 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1793 if (!mgr->tx_up_in_progress) {
1794 process_single_up_tx_qlock(mgr);
1796 mutex_unlock(&mgr->qlock);
1800 static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
1804 switch (dp_link_bw) {
1806 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
1807 dp_link_bw, dp_link_count);
1810 case DP_LINK_BW_1_62:
1811 *out = 3 * dp_link_count;
1813 case DP_LINK_BW_2_7:
1814 *out = 5 * dp_link_count;
1816 case DP_LINK_BW_5_4:
1817 *out = 10 * dp_link_count;
1824 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1825 * @mgr: manager to set state for
1826 * @mst_state: true to enable MST on this connector - false to disable.
1828 * This is called by the driver when it detects an MST capable device plugged
1829 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1831 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1834 struct drm_dp_mst_branch *mstb = NULL;
1836 mutex_lock(&mgr->lock);
1837 if (mst_state == mgr->mst_state)
1840 mgr->mst_state = mst_state;
1841 /* set the device into MST mode */
1843 WARN_ON(mgr->mst_primary);
1846 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1847 if (ret != DP_RECEIVER_CAP_SIZE) {
1848 DRM_DEBUG_KMS("failed to read DPCD\n");
1852 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
1853 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
1859 mgr->total_pbn = 2560;
1860 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1861 mgr->avail_slots = mgr->total_slots;
1863 /* add initial branch device at LCT 1 */
1864 mstb = drm_dp_add_mst_branch_device(1, NULL);
1871 /* give this the main reference */
1872 mgr->mst_primary = mstb;
1873 kref_get(&mgr->mst_primary->kref);
1876 struct drm_dp_payload reset_pay;
1877 reset_pay.start_slot = 0;
1878 reset_pay.num_slots = 0x3f;
1879 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1882 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1883 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1890 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1892 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1896 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1897 if (!mgr->guid_valid) {
1898 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1899 mgr->guid_valid = true;
1902 queue_work(system_long_wq, &mgr->work);
1906 /* disable MST on the device */
1907 mstb = mgr->mst_primary;
1908 mgr->mst_primary = NULL;
1909 /* this can fail if the device is gone */
1910 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1912 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1913 mgr->payload_mask = 0;
1914 set_bit(0, &mgr->payload_mask);
1918 mutex_unlock(&mgr->lock);
1920 drm_dp_put_mst_branch_device(mstb);
1924 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1927 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1928 * @mgr: manager to suspend
1930 * This function tells the MST device that we can't handle UP messages
1931 * anymore. This should stop it from sending any since we are suspended.
1933 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1935 mutex_lock(&mgr->lock);
1936 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1937 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1938 mutex_unlock(&mgr->lock);
1940 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1943 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1944 * @mgr: manager to resume
1946 * This will fetch DPCD and see if the device is still there,
1947 * if it is, it will rewrite the MSTM control bits, and return.
1949 * if the device fails this returns -1, and the driver should do
1950 * a full MST reprobe, in case we were undocked.
1952 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1956 mutex_lock(&mgr->lock);
1958 if (mgr->mst_primary) {
1960 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1961 if (sret != DP_RECEIVER_CAP_SIZE) {
1962 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1967 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1968 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1970 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1979 mutex_unlock(&mgr->lock);
1982 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
1984 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
1988 int replylen, origlen, curreply;
1990 struct drm_dp_sideband_msg_rx *msg;
1991 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
1992 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
1994 len = min(mgr->max_dpcd_transaction_bytes, 16);
1995 ret = drm_dp_dpcd_read(mgr->aux, basereg,
1998 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
2001 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
2003 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
2006 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
2011 while (replylen > 0) {
2012 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2013 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2016 DRM_DEBUG_KMS("failed to read a chunk\n");
2018 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2020 DRM_DEBUG_KMS("failed to build sideband msg\n");
2026 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2030 drm_dp_get_one_sb_msg(mgr, false);
2032 if (mgr->down_rep_recv.have_eomt) {
2033 struct drm_dp_sideband_msg_tx *txmsg;
2034 struct drm_dp_mst_branch *mstb;
2036 mstb = drm_dp_get_mst_branch_device(mgr,
2037 mgr->down_rep_recv.initial_hdr.lct,
2038 mgr->down_rep_recv.initial_hdr.rad);
2041 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2042 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2046 /* find the message */
2047 slot = mgr->down_rep_recv.initial_hdr.seqno;
2048 mutex_lock(&mgr->qlock);
2049 txmsg = mstb->tx_slots[slot];
2050 /* remove from slots */
2051 mutex_unlock(&mgr->qlock);
2054 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2056 mgr->down_rep_recv.initial_hdr.seqno,
2057 mgr->down_rep_recv.initial_hdr.lct,
2058 mgr->down_rep_recv.initial_hdr.rad[0],
2059 mgr->down_rep_recv.msg[0]);
2060 drm_dp_put_mst_branch_device(mstb);
2061 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2065 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2066 if (txmsg->reply.reply_type == 1) {
2067 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);
2070 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2071 drm_dp_put_mst_branch_device(mstb);
2073 mutex_lock(&mgr->qlock);
2074 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2075 mstb->tx_slots[slot] = NULL;
2076 mutex_unlock(&mgr->qlock);
2078 wake_up(&mgr->tx_waitq);
2083 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2086 drm_dp_get_one_sb_msg(mgr, true);
2088 if (mgr->up_req_recv.have_eomt) {
2089 struct drm_dp_sideband_msg_req_body msg;
2090 struct drm_dp_mst_branch *mstb;
2092 mstb = drm_dp_get_mst_branch_device(mgr,
2093 mgr->up_req_recv.initial_hdr.lct,
2094 mgr->up_req_recv.initial_hdr.rad);
2096 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2097 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2101 seqno = mgr->up_req_recv.initial_hdr.seqno;
2102 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2104 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2105 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2106 drm_dp_update_port(mstb, &msg.u.conn_stat);
2107 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);
2108 (*mgr->cbs->hotplug)(mgr);
2110 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2111 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2112 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2115 drm_dp_put_mst_branch_device(mstb);
2116 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2122 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2123 * @mgr: manager to notify irq for.
2124 * @esi: 4 bytes from SINK_COUNT_ESI
2126 * This should be called from the driver when it detects a short IRQ,
2127 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2128 * topology manager will process the sideband messages received as a result
2131 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2138 if (sc != mgr->sink_count) {
2139 mgr->sink_count = sc;
2143 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2144 ret = drm_dp_mst_handle_down_rep(mgr);
2148 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2149 ret |= drm_dp_mst_handle_up_req(mgr);
2153 drm_dp_mst_kick_tx(mgr);
2156 EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2159 * drm_dp_mst_detect_port() - get connection status for an MST port
2160 * @mgr: manager for this port
2161 * @port: unverified pointer to a port
2163 * This returns the current connection state for a port. It validates the
2164 * port pointer still exists so the caller doesn't require a reference
2166 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
2167 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2169 enum drm_connector_status status = connector_status_disconnected;
2171 /* we need to search for the port in the mgr in case its gone */
2172 port = drm_dp_get_validated_port_ref(mgr, port);
2174 return connector_status_disconnected;
2179 switch (port->pdt) {
2180 case DP_PEER_DEVICE_NONE:
2181 case DP_PEER_DEVICE_MST_BRANCHING:
2184 case DP_PEER_DEVICE_SST_SINK:
2185 status = connector_status_connected;
2186 /* for logical ports - cache the EDID */
2187 if (port->port_num >= 8 && !port->cached_edid) {
2188 port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
2191 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2193 status = connector_status_connected;
2197 drm_dp_put_port(port);
2200 EXPORT_SYMBOL(drm_dp_mst_detect_port);
2203 * drm_dp_mst_get_edid() - get EDID for an MST port
2204 * @connector: toplevel connector to get EDID for
2205 * @mgr: manager for this port
2206 * @port: unverified pointer to a port.
2208 * This returns an EDID for the port connected to a connector,
2209 * It validates the pointer still exists so the caller doesn't require a
2212 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2214 struct edid *edid = NULL;
2216 /* we need to search for the port in the mgr in case its gone */
2217 port = drm_dp_get_validated_port_ref(mgr, port);
2221 if (port->cached_edid)
2222 edid = drm_edid_duplicate(port->cached_edid);
2224 edid = drm_get_edid(connector, &port->aux.ddc);
2226 drm_mode_connector_set_tile_property(connector);
2227 drm_dp_put_port(port);
2230 EXPORT_SYMBOL(drm_dp_mst_get_edid);
2233 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2234 * @mgr: manager to use
2235 * @pbn: payload bandwidth to convert into slots.
2237 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2242 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2244 if (num_slots > mgr->avail_slots)
2248 EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2250 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2251 struct drm_dp_vcpi *vcpi, int pbn)
2256 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2258 if (num_slots > mgr->avail_slots)
2262 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2263 vcpi->num_slots = num_slots;
2265 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2272 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2273 * @mgr: manager for this port
2274 * @port: port to allocate a virtual channel for.
2275 * @pbn: payload bandwidth number to request
2276 * @slots: returned number of slots for this PBN.
2278 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2282 port = drm_dp_get_validated_port_ref(mgr, port);
2286 if (port->vcpi.vcpi > 0) {
2287 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2288 if (pbn == port->vcpi.pbn) {
2289 *slots = port->vcpi.num_slots;
2294 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2296 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2299 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2300 *slots = port->vcpi.num_slots;
2302 drm_dp_put_port(port);
2307 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2309 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2312 port = drm_dp_get_validated_port_ref(mgr, port);
2316 slots = port->vcpi.num_slots;
2317 drm_dp_put_port(port);
2320 EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots);
2323 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2324 * @mgr: manager for this port
2325 * @port: unverified pointer to a port.
2327 * This just resets the number of slots for the ports VCPI for later programming.
2329 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2331 port = drm_dp_get_validated_port_ref(mgr, port);
2334 port->vcpi.num_slots = 0;
2335 drm_dp_put_port(port);
2337 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2340 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2341 * @mgr: manager for this port
2342 * @port: unverified port to deallocate vcpi for
2344 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2346 port = drm_dp_get_validated_port_ref(mgr, port);
2350 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2351 port->vcpi.num_slots = 0;
2353 port->vcpi.aligned_pbn = 0;
2354 port->vcpi.vcpi = 0;
2355 drm_dp_put_port(port);
2357 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2359 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2360 int id, struct drm_dp_payload *payload)
2362 u8 payload_alloc[3], status;
2366 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2367 DP_PAYLOAD_TABLE_UPDATED);
2369 payload_alloc[0] = id;
2370 payload_alloc[1] = payload->start_slot;
2371 payload_alloc[2] = payload->num_slots;
2373 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2375 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2380 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2382 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2386 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2389 usleep_range(10000, 20000);
2392 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2403 * drm_dp_check_act_status() - Check ACT handled status.
2404 * @mgr: manager to use
2406 * Check the payload status bits in the DPCD for ACT handled completion.
2408 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2415 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2418 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2422 if (status & DP_PAYLOAD_ACT_HANDLED)
2427 } while (count < 30);
2429 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2430 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2438 EXPORT_SYMBOL(drm_dp_check_act_status);
2441 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2442 * @clock: dot clock for the mode
2443 * @bpp: bpp for the mode.
2445 * This uses the formula in the spec to calculate the PBN value for a mode.
2447 int drm_dp_calc_pbn_mode(int clock, int bpp)
2452 fixed20_12 margin, tmp;
2455 pix_bw.full = dfixed_const(clock);
2456 fbpp.full = dfixed_const(bpp);
2457 tmp.full = dfixed_const(8);
2458 fbpp.full = dfixed_div(fbpp, tmp);
2460 result.full = dfixed_mul(pix_bw, fbpp);
2461 margin.full = dfixed_const(54);
2462 tmp.full = dfixed_const(64);
2463 margin.full = dfixed_div(margin, tmp);
2464 result.full = dfixed_div(result, margin);
2466 margin.full = dfixed_const(1006);
2467 tmp.full = dfixed_const(1000);
2468 margin.full = dfixed_div(margin, tmp);
2469 result.full = dfixed_mul(result, margin);
2471 result.full = dfixed_div(result, tmp);
2472 result.full = dfixed_ceil(result);
2473 res = dfixed_trunc(result);
2476 EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2478 static int test_calc_pbn_mode(void)
2481 ret = drm_dp_calc_pbn_mode(154000, 30);
2484 ret = drm_dp_calc_pbn_mode(234000, 30);
2490 /* we want to kick the TX after we've ack the up/down IRQs. */
2491 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2493 queue_work(system_long_wq, &mgr->tx_work);
2496 static void drm_dp_mst_dump_mstb(struct seq_file *m,
2497 struct drm_dp_mst_branch *mstb)
2499 struct drm_dp_mst_port *port;
2500 int tabs = mstb->lct;
2504 for (i = 0; i < tabs; i++)
2508 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2509 list_for_each_entry(port, &mstb->ports, next) {
2510 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2512 drm_dp_mst_dump_mstb(m, port->mstb);
2516 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2521 for (i = 0; i < 4; i++) {
2522 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2532 * drm_dp_mst_dump_topology(): dump topology to seq file.
2533 * @m: seq_file to dump output to
2534 * @mgr: manager to dump current topology for.
2536 * helper to dump MST topology to a seq file for debugfs.
2538 void drm_dp_mst_dump_topology(struct seq_file *m,
2539 struct drm_dp_mst_topology_mgr *mgr)
2542 struct drm_dp_mst_port *port;
2543 mutex_lock(&mgr->lock);
2544 if (mgr->mst_primary)
2545 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2548 mutex_unlock(&mgr->lock);
2550 mutex_lock(&mgr->payload_lock);
2551 seq_printf(m, "vcpi: %lx\n", mgr->payload_mask);
2553 for (i = 0; i < mgr->max_payloads; i++) {
2554 if (mgr->proposed_vcpis[i]) {
2555 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2556 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2558 seq_printf(m, "vcpi %d:unsed\n", i);
2560 for (i = 0; i < mgr->max_payloads; i++) {
2561 seq_printf(m, "payload %d: %d, %d, %d\n",
2563 mgr->payloads[i].payload_state,
2564 mgr->payloads[i].start_slot,
2565 mgr->payloads[i].num_slots);
2569 mutex_unlock(&mgr->payload_lock);
2571 mutex_lock(&mgr->lock);
2572 if (mgr->mst_primary) {
2576 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2577 seq_printf(m, "dpcd: ");
2578 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2579 seq_printf(m, "%02x ", buf[i]);
2580 seq_printf(m, "\n");
2581 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2582 seq_printf(m, "faux/mst: ");
2583 for (i = 0; i < 2; i++)
2584 seq_printf(m, "%02x ", buf[i]);
2585 seq_printf(m, "\n");
2586 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2587 seq_printf(m, "mst ctrl: ");
2588 for (i = 0; i < 1; i++)
2589 seq_printf(m, "%02x ", buf[i]);
2590 seq_printf(m, "\n");
2592 bret = dump_dp_payload_table(mgr, buf);
2594 seq_printf(m, "payload table: ");
2595 for (i = 0; i < 63; i++)
2596 seq_printf(m, "%02x ", buf[i]);
2597 seq_printf(m, "\n");
2602 mutex_unlock(&mgr->lock);
2605 EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2607 static void drm_dp_tx_work(struct work_struct *work)
2609 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2611 mutex_lock(&mgr->qlock);
2612 if (mgr->tx_down_in_progress)
2613 process_single_down_tx_qlock(mgr);
2614 mutex_unlock(&mgr->qlock);
2617 static void drm_dp_destroy_connector_work(struct work_struct *work)
2619 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
2620 struct drm_dp_mst_port *port;
2623 * Not a regular list traverse as we have to drop the destroy
2624 * connector lock before destroying the connector, to avoid AB->BA
2625 * ordering between this lock and the config mutex.
2628 mutex_lock(&mgr->destroy_connector_lock);
2629 port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next);
2631 mutex_unlock(&mgr->destroy_connector_lock);
2634 list_del(&port->next);
2635 mutex_unlock(&mgr->destroy_connector_lock);
2637 mgr->cbs->destroy_connector(mgr, port->connector);
2639 drm_dp_port_teardown_pdt(port, port->pdt);
2641 if (!port->input && port->vcpi.vcpi > 0)
2642 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2648 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2649 * @mgr: manager struct to initialise
2650 * @dev: device providing this structure - for i2c addition.
2651 * @aux: DP helper aux channel to talk to this device
2652 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2653 * @max_payloads: maximum number of payloads this GPU can source
2654 * @conn_base_id: the connector object ID the MST device is connected to.
2656 * Return 0 for success, or negative error code on failure
2658 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2659 struct device *dev, struct drm_dp_aux *aux,
2660 int max_dpcd_transaction_bytes,
2661 int max_payloads, int conn_base_id)
2663 mutex_init(&mgr->lock);
2664 mutex_init(&mgr->qlock);
2665 mutex_init(&mgr->payload_lock);
2666 mutex_init(&mgr->destroy_connector_lock);
2667 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2668 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2669 INIT_LIST_HEAD(&mgr->destroy_connector_list);
2670 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2671 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2672 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work);
2673 init_waitqueue_head(&mgr->tx_waitq);
2676 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2677 mgr->max_payloads = max_payloads;
2678 mgr->conn_base_id = conn_base_id;
2679 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2682 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2683 if (!mgr->proposed_vcpis)
2685 set_bit(0, &mgr->payload_mask);
2686 test_calc_pbn_mode();
2689 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2692 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2693 * @mgr: manager to destroy
2695 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2697 flush_work(&mgr->destroy_connector_work);
2698 mutex_lock(&mgr->payload_lock);
2699 kfree(mgr->payloads);
2700 mgr->payloads = NULL;
2701 kfree(mgr->proposed_vcpis);
2702 mgr->proposed_vcpis = NULL;
2703 mutex_unlock(&mgr->payload_lock);
2707 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2710 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2713 struct drm_dp_aux *aux = adapter->algo_data;
2714 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2715 struct drm_dp_mst_branch *mstb;
2716 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2718 bool reading = false;
2719 struct drm_dp_sideband_msg_req_body msg;
2720 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2723 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2727 /* construct i2c msg */
2728 /* see if last msg is a read */
2729 if (msgs[num - 1].flags & I2C_M_RD)
2733 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2738 msg.req_type = DP_REMOTE_I2C_READ;
2739 msg.u.i2c_read.num_transactions = num - 1;
2740 msg.u.i2c_read.port_number = port->port_num;
2741 for (i = 0; i < num - 1; i++) {
2742 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2743 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2744 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2746 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2747 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2749 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2756 drm_dp_encode_sideband_req(&msg, txmsg);
2758 drm_dp_queue_down_tx(mgr, txmsg);
2760 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2763 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2767 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2771 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2776 drm_dp_put_mst_branch_device(mstb);
2780 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2782 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2783 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2784 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2785 I2C_FUNC_10BIT_ADDR;
2788 static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2789 .functionality = drm_dp_mst_i2c_functionality,
2790 .master_xfer = drm_dp_mst_i2c_xfer,
2794 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2795 * @aux: DisplayPort AUX channel
2797 * Returns 0 on success or a negative error code on failure.
2799 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2801 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2802 aux->ddc.algo_data = aux;
2803 aux->ddc.retries = 3;
2805 aux->ddc.class = I2C_CLASS_DDC;
2806 aux->ddc.owner = THIS_MODULE;
2807 aux->ddc.dev.parent = aux->dev;
2808 aux->ddc.dev.of_node = aux->dev->of_node;
2810 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2811 sizeof(aux->ddc.name));
2813 return i2c_add_adapter(&aux->ddc);
2817 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2818 * @aux: DisplayPort AUX channel
2820 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2822 i2c_del_adapter(&aux->ddc);