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 vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1);
696 if (vcpi_ret > mgr->max_payloads) {
698 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret);
702 set_bit(ret, &mgr->payload_mask);
703 set_bit(vcpi_ret, &mgr->vcpi_mask);
704 vcpi->vcpi = vcpi_ret + 1;
705 mgr->proposed_vcpis[ret - 1] = vcpi;
707 mutex_unlock(&mgr->payload_lock);
711 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
718 mutex_lock(&mgr->payload_lock);
719 DRM_DEBUG_KMS("putting payload %d\n", vcpi);
720 clear_bit(vcpi - 1, &mgr->vcpi_mask);
722 for (i = 0; i < mgr->max_payloads; i++) {
723 if (mgr->proposed_vcpis[i])
724 if (mgr->proposed_vcpis[i]->vcpi == vcpi) {
725 mgr->proposed_vcpis[i] = NULL;
726 clear_bit(i + 1, &mgr->payload_mask);
729 mutex_unlock(&mgr->payload_lock);
732 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
733 struct drm_dp_sideband_msg_tx *txmsg)
736 mutex_lock(&mgr->qlock);
737 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
738 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
739 mutex_unlock(&mgr->qlock);
743 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
744 struct drm_dp_sideband_msg_tx *txmsg)
746 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
749 ret = wait_event_timeout(mgr->tx_waitq,
750 check_txmsg_state(mgr, txmsg),
752 mutex_lock(&mstb->mgr->qlock);
754 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
759 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
761 /* dump some state */
765 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
766 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
767 list_del(&txmsg->next);
770 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
771 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
772 mstb->tx_slots[txmsg->seqno] = NULL;
776 mutex_unlock(&mgr->qlock);
781 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
783 struct drm_dp_mst_branch *mstb;
785 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
791 memcpy(mstb->rad, rad, lct / 2);
792 INIT_LIST_HEAD(&mstb->ports);
793 kref_init(&mstb->kref);
797 static void drm_dp_destroy_mst_branch_device(struct kref *kref)
799 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
800 struct drm_dp_mst_port *port, *tmp;
801 bool wake_tx = false;
803 cancel_work_sync(&mstb->mgr->work);
806 * destroy all ports - don't need lock
807 * as there are no more references to the mst branch
808 * device at this point.
810 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
811 list_del(&port->next);
812 drm_dp_put_port(port);
815 /* drop any tx slots msg */
816 mutex_lock(&mstb->mgr->qlock);
817 if (mstb->tx_slots[0]) {
818 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
819 mstb->tx_slots[0] = NULL;
822 if (mstb->tx_slots[1]) {
823 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
824 mstb->tx_slots[1] = NULL;
827 mutex_unlock(&mstb->mgr->qlock);
830 wake_up(&mstb->mgr->tx_waitq);
834 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
836 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
840 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
843 case DP_PEER_DEVICE_DP_LEGACY_CONV:
844 case DP_PEER_DEVICE_SST_SINK:
845 /* remove i2c over sideband */
846 drm_dp_mst_unregister_i2c_bus(&port->aux);
848 case DP_PEER_DEVICE_MST_BRANCHING:
849 drm_dp_put_mst_branch_device(port->mstb);
855 static void drm_dp_destroy_port(struct kref *kref)
857 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
858 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
860 port->vcpi.num_slots = 0;
862 (*port->mgr->cbs->destroy_connector)(mgr, port->connector);
863 drm_dp_port_teardown_pdt(port, port->pdt);
865 if (!port->input && port->vcpi.vcpi > 0)
866 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
870 (*mgr->cbs->hotplug)(mgr);
873 static void drm_dp_put_port(struct drm_dp_mst_port *port)
875 kref_put(&port->kref, drm_dp_destroy_port);
878 static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find)
880 struct drm_dp_mst_port *port;
881 struct drm_dp_mst_branch *rmstb;
882 if (to_find == mstb) {
883 kref_get(&mstb->kref);
886 list_for_each_entry(port, &mstb->ports, next) {
888 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
896 static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb)
898 struct drm_dp_mst_branch *rmstb = NULL;
899 mutex_lock(&mgr->lock);
900 if (mgr->mst_primary)
901 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
902 mutex_unlock(&mgr->lock);
906 static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find)
908 struct drm_dp_mst_port *port, *mport;
910 list_for_each_entry(port, &mstb->ports, next) {
911 if (port == to_find) {
912 kref_get(&port->kref);
916 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
924 static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
926 struct drm_dp_mst_port *rport = NULL;
927 mutex_lock(&mgr->lock);
928 if (mgr->mst_primary)
929 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
930 mutex_unlock(&mgr->lock);
934 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
936 struct drm_dp_mst_port *port;
938 list_for_each_entry(port, &mstb->ports, next) {
939 if (port->port_num == port_num) {
940 kref_get(&port->kref);
949 * calculate a new RAD for this MST branch device
950 * if parent has an LCT of 2 then it has 1 nibble of RAD,
951 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
953 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
956 int lct = port->parent->lct;
960 memcpy(rad, port->parent->rad, idx);
961 shift = (lct % 2) ? 4 : 0;
965 rad[idx] |= port->port_num << shift;
970 * return sends link address for new mstb
972 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
976 bool send_link = false;
978 case DP_PEER_DEVICE_DP_LEGACY_CONV:
979 case DP_PEER_DEVICE_SST_SINK:
980 /* add i2c over sideband */
981 ret = drm_dp_mst_register_i2c_bus(&port->aux);
983 case DP_PEER_DEVICE_MST_BRANCHING:
984 lct = drm_dp_calculate_rad(port, rad);
986 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
987 port->mstb->mgr = port->mgr;
988 port->mstb->port_parent = port;
996 static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
997 struct drm_dp_mst_port *port)
1000 if (port->dpcd_rev >= 0x12) {
1001 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
1002 if (!port->guid_valid) {
1003 ret = drm_dp_send_dpcd_write(mstb->mgr,
1007 port->guid_valid = true;
1012 static void build_mst_prop_path(struct drm_dp_mst_port *port,
1013 struct drm_dp_mst_branch *mstb,
1015 size_t proppath_size)
1019 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
1020 for (i = 0; i < (mstb->lct - 1); i++) {
1021 int shift = (i % 2) ? 0 : 4;
1022 int port_num = mstb->rad[i / 2] >> shift;
1023 snprintf(temp, sizeof(temp), "-%d", port_num);
1024 strlcat(proppath, temp, proppath_size);
1026 snprintf(temp, sizeof(temp), "-%d", port->port_num);
1027 strlcat(proppath, temp, proppath_size);
1030 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1032 struct drm_dp_link_addr_reply_port *port_msg)
1034 struct drm_dp_mst_port *port;
1036 bool created = false;
1039 port = drm_dp_get_port(mstb, port_msg->port_number);
1041 port = kzalloc(sizeof(*port), GFP_KERNEL);
1044 kref_init(&port->kref);
1045 port->parent = mstb;
1046 port->port_num = port_msg->port_number;
1047 port->mgr = mstb->mgr;
1048 port->aux.name = "DPMST";
1049 port->aux.dev = dev;
1052 old_pdt = port->pdt;
1053 old_ddps = port->ddps;
1056 port->pdt = port_msg->peer_device_type;
1057 port->input = port_msg->input_port;
1058 port->mcs = port_msg->mcs;
1059 port->ddps = port_msg->ddps;
1060 port->ldps = port_msg->legacy_device_plug_status;
1061 port->dpcd_rev = port_msg->dpcd_revision;
1062 port->num_sdp_streams = port_msg->num_sdp_streams;
1063 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1064 memcpy(port->guid, port_msg->peer_guid, 16);
1066 /* manage mstb port lists with mgr lock - take a reference
1069 mutex_lock(&mstb->mgr->lock);
1070 kref_get(&port->kref);
1071 list_add(&port->next, &mstb->ports);
1072 mutex_unlock(&mstb->mgr->lock);
1075 if (old_ddps != port->ddps) {
1077 drm_dp_check_port_guid(mstb, port);
1079 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1081 port->guid_valid = false;
1082 port->available_pbn = 0;
1086 if (old_pdt != port->pdt && !port->input) {
1087 drm_dp_port_teardown_pdt(port, old_pdt);
1089 ret = drm_dp_port_setup_pdt(port);
1091 drm_dp_send_link_address(mstb->mgr, port->mstb);
1092 port->mstb->link_address_sent = true;
1096 if (created && !port->input) {
1098 build_mst_prop_path(port, mstb, proppath, sizeof(proppath));
1099 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1102 /* put reference to this port */
1103 drm_dp_put_port(port);
1106 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1107 struct drm_dp_connection_status_notify *conn_stat)
1109 struct drm_dp_mst_port *port;
1112 bool dowork = false;
1113 port = drm_dp_get_port(mstb, conn_stat->port_number);
1117 old_ddps = port->ddps;
1118 old_pdt = port->pdt;
1119 port->pdt = conn_stat->peer_device_type;
1120 port->mcs = conn_stat->message_capability_status;
1121 port->ldps = conn_stat->legacy_device_plug_status;
1122 port->ddps = conn_stat->displayport_device_plug_status;
1124 if (old_ddps != port->ddps) {
1126 drm_dp_check_port_guid(mstb, port);
1129 port->guid_valid = false;
1130 port->available_pbn = 0;
1133 if (old_pdt != port->pdt && !port->input) {
1134 drm_dp_port_teardown_pdt(port, old_pdt);
1136 if (drm_dp_port_setup_pdt(port))
1140 drm_dp_put_port(port);
1142 queue_work(system_long_wq, &mstb->mgr->work);
1146 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1149 struct drm_dp_mst_branch *mstb;
1150 struct drm_dp_mst_port *port;
1152 /* find the port by iterating down */
1153 mstb = mgr->mst_primary;
1155 for (i = 0; i < lct - 1; i++) {
1156 int shift = (i % 2) ? 0 : 4;
1157 int port_num = rad[i / 2] >> shift;
1159 list_for_each_entry(port, &mstb->ports, next) {
1160 if (port->port_num == port_num) {
1162 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1171 kref_get(&mstb->kref);
1175 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1176 struct drm_dp_mst_branch *mstb)
1178 struct drm_dp_mst_port *port;
1180 if (!mstb->link_address_sent) {
1181 drm_dp_send_link_address(mgr, mstb);
1182 mstb->link_address_sent = true;
1184 list_for_each_entry(port, &mstb->ports, next) {
1191 if (!port->available_pbn)
1192 drm_dp_send_enum_path_resources(mgr, mstb, port);
1195 drm_dp_check_and_send_link_address(mgr, port->mstb);
1199 static void drm_dp_mst_link_probe_work(struct work_struct *work)
1201 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1203 drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
1207 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1210 static u8 zero_guid[16];
1212 if (!memcmp(guid, zero_guid, 16)) {
1213 u64 salt = get_jiffies_64();
1214 memcpy(&guid[0], &salt, sizeof(u64));
1215 memcpy(&guid[8], &salt, sizeof(u64));
1222 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1224 struct drm_dp_sideband_msg_req_body req;
1226 req.req_type = DP_REMOTE_DPCD_READ;
1227 req.u.dpcd_read.port_number = port_num;
1228 req.u.dpcd_read.dpcd_address = offset;
1229 req.u.dpcd_read.num_bytes = num_bytes;
1230 drm_dp_encode_sideband_req(&req, msg);
1236 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1237 bool up, u8 *msg, int len)
1240 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1241 int tosend, total, offset;
1248 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1250 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1253 if (ret != tosend) {
1254 if (ret == -EIO && retries < 5) {
1258 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1265 } while (total > 0);
1269 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1270 struct drm_dp_sideband_msg_tx *txmsg)
1272 struct drm_dp_mst_branch *mstb = txmsg->dst;
1274 /* both msg slots are full */
1275 if (txmsg->seqno == -1) {
1276 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1277 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1280 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1281 txmsg->seqno = mstb->last_seqno;
1282 mstb->last_seqno ^= 1;
1283 } else if (mstb->tx_slots[0] == NULL)
1287 mstb->tx_slots[txmsg->seqno] = txmsg;
1290 hdr->path_msg = txmsg->path_msg;
1291 hdr->lct = mstb->lct;
1292 hdr->lcr = mstb->lct - 1;
1294 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1295 hdr->seqno = txmsg->seqno;
1299 * process a single block of the next message in the sideband queue
1301 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1302 struct drm_dp_sideband_msg_tx *txmsg,
1306 struct drm_dp_sideband_msg_hdr hdr;
1307 int len, space, idx, tosend;
1310 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1312 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1314 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1317 /* make hdr from dst mst - for replies use seqno
1318 otherwise assign one */
1319 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1323 /* amount left to send in this message */
1324 len = txmsg->cur_len - txmsg->cur_offset;
1326 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1327 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1329 tosend = min(len, space);
1330 if (len == txmsg->cur_len)
1336 hdr.msg_len = tosend + 1;
1337 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1338 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1339 /* add crc at end */
1340 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1343 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1345 DRM_DEBUG_KMS("sideband msg failed to send\n");
1349 txmsg->cur_offset += tosend;
1350 if (txmsg->cur_offset == txmsg->cur_len) {
1351 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1357 /* must be called holding qlock */
1358 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1360 struct drm_dp_sideband_msg_tx *txmsg;
1363 /* construct a chunk from the first msg in the tx_msg queue */
1364 if (list_empty(&mgr->tx_msg_downq)) {
1365 mgr->tx_down_in_progress = false;
1368 mgr->tx_down_in_progress = true;
1370 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1371 ret = process_single_tx_qlock(mgr, txmsg, false);
1373 /* txmsg is sent it should be in the slots now */
1374 list_del(&txmsg->next);
1376 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1377 list_del(&txmsg->next);
1378 if (txmsg->seqno != -1)
1379 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1380 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1381 wake_up(&mgr->tx_waitq);
1383 if (list_empty(&mgr->tx_msg_downq)) {
1384 mgr->tx_down_in_progress = false;
1389 /* called holding qlock */
1390 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1392 struct drm_dp_sideband_msg_tx *txmsg;
1395 /* construct a chunk from the first msg in the tx_msg queue */
1396 if (list_empty(&mgr->tx_msg_upq)) {
1397 mgr->tx_up_in_progress = false;
1401 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1402 ret = process_single_tx_qlock(mgr, txmsg, true);
1404 /* up txmsgs aren't put in slots - so free after we send it */
1405 list_del(&txmsg->next);
1408 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1409 mgr->tx_up_in_progress = true;
1412 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1413 struct drm_dp_sideband_msg_tx *txmsg)
1415 mutex_lock(&mgr->qlock);
1416 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1417 if (!mgr->tx_down_in_progress)
1418 process_single_down_tx_qlock(mgr);
1419 mutex_unlock(&mgr->qlock);
1422 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1423 struct drm_dp_mst_branch *mstb)
1426 struct drm_dp_sideband_msg_tx *txmsg;
1429 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1434 len = build_link_address(txmsg);
1436 drm_dp_queue_down_tx(mgr, txmsg);
1438 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1442 if (txmsg->reply.reply_type == 1)
1443 DRM_DEBUG_KMS("link address nak received\n");
1445 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1446 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1447 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,
1448 txmsg->reply.u.link_addr.ports[i].input_port,
1449 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1450 txmsg->reply.u.link_addr.ports[i].port_number,
1451 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1452 txmsg->reply.u.link_addr.ports[i].mcs,
1453 txmsg->reply.u.link_addr.ports[i].ddps,
1454 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1455 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1456 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1458 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1459 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1461 (*mgr->cbs->hotplug)(mgr);
1464 DRM_DEBUG_KMS("link address failed %d\n", ret);
1470 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1471 struct drm_dp_mst_branch *mstb,
1472 struct drm_dp_mst_port *port)
1475 struct drm_dp_sideband_msg_tx *txmsg;
1478 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1483 len = build_enum_path_resources(txmsg, port->port_num);
1485 drm_dp_queue_down_tx(mgr, txmsg);
1487 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1489 if (txmsg->reply.reply_type == 1)
1490 DRM_DEBUG_KMS("enum path resources nak received\n");
1492 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1493 DRM_ERROR("got incorrect port in response\n");
1494 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,
1495 txmsg->reply.u.path_resources.avail_payload_bw_number);
1496 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1504 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1505 struct drm_dp_mst_port *port,
1509 struct drm_dp_sideband_msg_tx *txmsg;
1510 struct drm_dp_mst_branch *mstb;
1513 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1517 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1524 len = build_allocate_payload(txmsg, port->port_num,
1528 drm_dp_queue_down_tx(mgr, txmsg);
1530 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1532 if (txmsg->reply.reply_type == 1) {
1539 drm_dp_put_mst_branch_device(mstb);
1543 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1545 struct drm_dp_payload *payload)
1549 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1551 payload->payload_state = 0;
1554 payload->payload_state = DP_PAYLOAD_LOCAL;
1558 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1559 struct drm_dp_mst_port *port,
1561 struct drm_dp_payload *payload)
1564 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1567 payload->payload_state = DP_PAYLOAD_REMOTE;
1571 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1572 struct drm_dp_mst_port *port,
1574 struct drm_dp_payload *payload)
1576 DRM_DEBUG_KMS("\n");
1577 /* its okay for these to fail */
1579 drm_dp_payload_send_msg(mgr, port, id, 0);
1582 drm_dp_dpcd_write_payload(mgr, id, payload);
1583 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
1587 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1589 struct drm_dp_payload *payload)
1591 payload->payload_state = 0;
1596 * drm_dp_update_payload_part1() - Execute payload update part 1
1597 * @mgr: manager to use.
1599 * This iterates over all proposed virtual channels, and tries to
1600 * allocate space in the link for them. For 0->slots transitions,
1601 * this step just writes the VCPI to the MST device. For slots->0
1602 * transitions, this writes the updated VCPIs and removes the
1603 * remote VC payloads.
1605 * after calling this the driver should generate ACT and payload
1608 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1612 struct drm_dp_payload req_payload;
1613 struct drm_dp_mst_port *port;
1615 mutex_lock(&mgr->payload_lock);
1616 for (i = 0; i < mgr->max_payloads; i++) {
1617 /* solve the current payloads - compare to the hw ones
1618 - update the hw view */
1619 req_payload.start_slot = cur_slots;
1620 if (mgr->proposed_vcpis[i]) {
1621 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1622 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1625 req_payload.num_slots = 0;
1628 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1629 mgr->payloads[i].start_slot = req_payload.start_slot;
1631 /* work out what is required to happen with this payload */
1632 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
1634 /* need to push an update for this payload */
1635 if (req_payload.num_slots) {
1636 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
1637 mgr->payloads[i].num_slots = req_payload.num_slots;
1638 } else if (mgr->payloads[i].num_slots) {
1639 mgr->payloads[i].num_slots = 0;
1640 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
1641 req_payload.payload_state = mgr->payloads[i].payload_state;
1642 mgr->payloads[i].start_slot = 0;
1644 mgr->payloads[i].payload_state = req_payload.payload_state;
1646 cur_slots += req_payload.num_slots;
1649 for (i = 0; i < mgr->max_payloads; i++) {
1650 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1651 DRM_DEBUG_KMS("removing payload %d\n", i);
1652 for (j = i; j < mgr->max_payloads - 1; j++) {
1653 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1654 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1655 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1656 set_bit(j + 1, &mgr->payload_mask);
1658 clear_bit(j + 1, &mgr->payload_mask);
1661 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1662 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1663 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1667 mutex_unlock(&mgr->payload_lock);
1671 EXPORT_SYMBOL(drm_dp_update_payload_part1);
1674 * drm_dp_update_payload_part2() - Execute payload update part 2
1675 * @mgr: manager to use.
1677 * This iterates over all proposed virtual channels, and tries to
1678 * allocate space in the link for them. For 0->slots transitions,
1679 * this step writes the remote VC payload commands. For slots->0
1680 * this just resets some internal state.
1682 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1684 struct drm_dp_mst_port *port;
1687 mutex_lock(&mgr->payload_lock);
1688 for (i = 0; i < mgr->max_payloads; i++) {
1690 if (!mgr->proposed_vcpis[i])
1693 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1695 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1696 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1697 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1698 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1699 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1702 mutex_unlock(&mgr->payload_lock);
1706 mutex_unlock(&mgr->payload_lock);
1709 EXPORT_SYMBOL(drm_dp_update_payload_part2);
1711 #if 0 /* unused as of yet */
1712 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1713 struct drm_dp_mst_port *port,
1714 int offset, int size)
1717 struct drm_dp_sideband_msg_tx *txmsg;
1719 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1723 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1724 txmsg->dst = port->parent;
1726 drm_dp_queue_down_tx(mgr, txmsg);
1732 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1733 struct drm_dp_mst_port *port,
1734 int offset, int size, u8 *bytes)
1738 struct drm_dp_sideband_msg_tx *txmsg;
1739 struct drm_dp_mst_branch *mstb;
1741 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1745 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1751 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1754 drm_dp_queue_down_tx(mgr, txmsg);
1756 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1758 if (txmsg->reply.reply_type == 1) {
1765 drm_dp_put_mst_branch_device(mstb);
1769 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1771 struct drm_dp_sideband_msg_reply_body reply;
1773 reply.reply_type = 1;
1774 reply.req_type = req_type;
1775 drm_dp_encode_sideband_reply(&reply, msg);
1779 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1780 struct drm_dp_mst_branch *mstb,
1781 int req_type, int seqno, bool broadcast)
1783 struct drm_dp_sideband_msg_tx *txmsg;
1785 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1790 txmsg->seqno = seqno;
1791 drm_dp_encode_up_ack_reply(txmsg, req_type);
1793 mutex_lock(&mgr->qlock);
1794 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1795 if (!mgr->tx_up_in_progress) {
1796 process_single_up_tx_qlock(mgr);
1798 mutex_unlock(&mgr->qlock);
1802 static int drm_dp_get_vc_payload_bw(int dp_link_bw, int dp_link_count)
1804 switch (dp_link_bw) {
1805 case DP_LINK_BW_1_62:
1806 return 3 * dp_link_count;
1807 case DP_LINK_BW_2_7:
1808 return 5 * dp_link_count;
1809 case DP_LINK_BW_5_4:
1810 return 10 * dp_link_count;
1816 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1817 * @mgr: manager to set state for
1818 * @mst_state: true to enable MST on this connector - false to disable.
1820 * This is called by the driver when it detects an MST capable device plugged
1821 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1823 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1826 struct drm_dp_mst_branch *mstb = NULL;
1828 mutex_lock(&mgr->lock);
1829 if (mst_state == mgr->mst_state)
1832 mgr->mst_state = mst_state;
1833 /* set the device into MST mode */
1835 WARN_ON(mgr->mst_primary);
1838 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1839 if (ret != DP_RECEIVER_CAP_SIZE) {
1840 DRM_DEBUG_KMS("failed to read DPCD\n");
1844 mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1], mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK);
1845 mgr->total_pbn = 2560;
1846 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1847 mgr->avail_slots = mgr->total_slots;
1849 /* add initial branch device at LCT 1 */
1850 mstb = drm_dp_add_mst_branch_device(1, NULL);
1857 /* give this the main reference */
1858 mgr->mst_primary = mstb;
1859 kref_get(&mgr->mst_primary->kref);
1862 struct drm_dp_payload reset_pay;
1863 reset_pay.start_slot = 0;
1864 reset_pay.num_slots = 0x3f;
1865 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1868 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1869 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1876 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1878 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1882 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1883 if (!mgr->guid_valid) {
1884 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1885 mgr->guid_valid = true;
1888 queue_work(system_long_wq, &mgr->work);
1892 /* disable MST on the device */
1893 mstb = mgr->mst_primary;
1894 mgr->mst_primary = NULL;
1895 /* this can fail if the device is gone */
1896 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1898 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1899 mgr->payload_mask = 0;
1900 set_bit(0, &mgr->payload_mask);
1905 mutex_unlock(&mgr->lock);
1907 drm_dp_put_mst_branch_device(mstb);
1911 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1914 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1915 * @mgr: manager to suspend
1917 * This function tells the MST device that we can't handle UP messages
1918 * anymore. This should stop it from sending any since we are suspended.
1920 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1922 mutex_lock(&mgr->lock);
1923 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1924 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1925 mutex_unlock(&mgr->lock);
1927 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1930 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1931 * @mgr: manager to resume
1933 * This will fetch DPCD and see if the device is still there,
1934 * if it is, it will rewrite the MSTM control bits, and return.
1936 * if the device fails this returns -1, and the driver should do
1937 * a full MST reprobe, in case we were undocked.
1939 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1943 mutex_lock(&mgr->lock);
1945 if (mgr->mst_primary) {
1947 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1948 if (sret != DP_RECEIVER_CAP_SIZE) {
1949 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1954 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1955 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1957 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1966 mutex_unlock(&mgr->lock);
1969 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
1971 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
1975 int replylen, origlen, curreply;
1977 struct drm_dp_sideband_msg_rx *msg;
1978 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
1979 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
1981 len = min(mgr->max_dpcd_transaction_bytes, 16);
1982 ret = drm_dp_dpcd_read(mgr->aux, basereg,
1985 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
1988 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
1990 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
1993 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
1998 while (replylen > 0) {
1999 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2000 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2003 DRM_DEBUG_KMS("failed to read a chunk\n");
2005 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2007 DRM_DEBUG_KMS("failed to build sideband msg\n");
2013 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2017 drm_dp_get_one_sb_msg(mgr, false);
2019 if (mgr->down_rep_recv.have_eomt) {
2020 struct drm_dp_sideband_msg_tx *txmsg;
2021 struct drm_dp_mst_branch *mstb;
2023 mstb = drm_dp_get_mst_branch_device(mgr,
2024 mgr->down_rep_recv.initial_hdr.lct,
2025 mgr->down_rep_recv.initial_hdr.rad);
2028 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2029 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2033 /* find the message */
2034 slot = mgr->down_rep_recv.initial_hdr.seqno;
2035 mutex_lock(&mgr->qlock);
2036 txmsg = mstb->tx_slots[slot];
2037 /* remove from slots */
2038 mutex_unlock(&mgr->qlock);
2041 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2043 mgr->down_rep_recv.initial_hdr.seqno,
2044 mgr->down_rep_recv.initial_hdr.lct,
2045 mgr->down_rep_recv.initial_hdr.rad[0],
2046 mgr->down_rep_recv.msg[0]);
2047 drm_dp_put_mst_branch_device(mstb);
2048 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2052 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2053 if (txmsg->reply.reply_type == 1) {
2054 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);
2057 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2058 drm_dp_put_mst_branch_device(mstb);
2060 mutex_lock(&mgr->qlock);
2061 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2062 mstb->tx_slots[slot] = NULL;
2063 mutex_unlock(&mgr->qlock);
2065 wake_up(&mgr->tx_waitq);
2070 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2073 drm_dp_get_one_sb_msg(mgr, true);
2075 if (mgr->up_req_recv.have_eomt) {
2076 struct drm_dp_sideband_msg_req_body msg;
2077 struct drm_dp_mst_branch *mstb;
2079 mstb = drm_dp_get_mst_branch_device(mgr,
2080 mgr->up_req_recv.initial_hdr.lct,
2081 mgr->up_req_recv.initial_hdr.rad);
2083 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2084 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2088 seqno = mgr->up_req_recv.initial_hdr.seqno;
2089 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2091 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2092 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2093 drm_dp_update_port(mstb, &msg.u.conn_stat);
2094 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);
2095 (*mgr->cbs->hotplug)(mgr);
2097 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2098 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2099 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2102 drm_dp_put_mst_branch_device(mstb);
2103 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2109 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2110 * @mgr: manager to notify irq for.
2111 * @esi: 4 bytes from SINK_COUNT_ESI
2112 * @handled: whether the hpd interrupt was consumed or not
2114 * This should be called from the driver when it detects a short IRQ,
2115 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2116 * topology manager will process the sideband messages received as a result
2119 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2126 if (sc != mgr->sink_count) {
2127 mgr->sink_count = sc;
2131 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2132 ret = drm_dp_mst_handle_down_rep(mgr);
2136 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2137 ret |= drm_dp_mst_handle_up_req(mgr);
2141 drm_dp_mst_kick_tx(mgr);
2144 EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2147 * drm_dp_mst_detect_port() - get connection status for an MST port
2148 * @mgr: manager for this port
2149 * @port: unverified pointer to a port
2151 * This returns the current connection state for a port. It validates the
2152 * port pointer still exists so the caller doesn't require a reference
2154 enum drm_connector_status drm_dp_mst_detect_port(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2156 enum drm_connector_status status = connector_status_disconnected;
2158 /* we need to search for the port in the mgr in case its gone */
2159 port = drm_dp_get_validated_port_ref(mgr, port);
2161 return connector_status_disconnected;
2166 switch (port->pdt) {
2167 case DP_PEER_DEVICE_NONE:
2168 case DP_PEER_DEVICE_MST_BRANCHING:
2171 case DP_PEER_DEVICE_SST_SINK:
2172 status = connector_status_connected;
2174 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2176 status = connector_status_connected;
2180 drm_dp_put_port(port);
2183 EXPORT_SYMBOL(drm_dp_mst_detect_port);
2186 * drm_dp_mst_get_edid() - get EDID for an MST port
2187 * @connector: toplevel connector to get EDID for
2188 * @mgr: manager for this port
2189 * @port: unverified pointer to a port.
2191 * This returns an EDID for the port connected to a connector,
2192 * It validates the pointer still exists so the caller doesn't require a
2195 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2197 struct edid *edid = NULL;
2199 /* we need to search for the port in the mgr in case its gone */
2200 port = drm_dp_get_validated_port_ref(mgr, port);
2204 edid = drm_get_edid(connector, &port->aux.ddc);
2205 drm_dp_put_port(port);
2208 EXPORT_SYMBOL(drm_dp_mst_get_edid);
2211 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2212 * @mgr: manager to use
2213 * @pbn: payload bandwidth to convert into slots.
2215 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2220 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2222 if (num_slots > mgr->avail_slots)
2226 EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2228 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2229 struct drm_dp_vcpi *vcpi, int pbn)
2234 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2236 if (num_slots > mgr->avail_slots)
2240 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2241 vcpi->num_slots = num_slots;
2243 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2250 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2251 * @mgr: manager for this port
2252 * @port: port to allocate a virtual channel for.
2253 * @pbn: payload bandwidth number to request
2254 * @slots: returned number of slots for this PBN.
2256 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2260 port = drm_dp_get_validated_port_ref(mgr, port);
2264 if (port->vcpi.vcpi > 0) {
2265 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2266 if (pbn == port->vcpi.pbn) {
2267 *slots = port->vcpi.num_slots;
2272 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2274 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2277 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2278 *slots = port->vcpi.num_slots;
2280 drm_dp_put_port(port);
2285 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2288 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2289 * @mgr: manager for this port
2290 * @port: unverified pointer to a port.
2292 * This just resets the number of slots for the ports VCPI for later programming.
2294 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2296 port = drm_dp_get_validated_port_ref(mgr, port);
2299 port->vcpi.num_slots = 0;
2300 drm_dp_put_port(port);
2302 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2305 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2306 * @mgr: manager for this port
2307 * @port: unverified port to deallocate vcpi for
2309 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2311 port = drm_dp_get_validated_port_ref(mgr, port);
2315 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2316 port->vcpi.num_slots = 0;
2318 port->vcpi.aligned_pbn = 0;
2319 port->vcpi.vcpi = 0;
2320 drm_dp_put_port(port);
2322 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2324 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2325 int id, struct drm_dp_payload *payload)
2327 u8 payload_alloc[3], status;
2331 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2332 DP_PAYLOAD_TABLE_UPDATED);
2334 payload_alloc[0] = id;
2335 payload_alloc[1] = payload->start_slot;
2336 payload_alloc[2] = payload->num_slots;
2338 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2340 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2345 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2347 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2351 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2354 usleep_range(10000, 20000);
2357 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2368 * drm_dp_check_act_status() - Check ACT handled status.
2369 * @mgr: manager to use
2371 * Check the payload status bits in the DPCD for ACT handled completion.
2373 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2380 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2383 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2387 if (status & DP_PAYLOAD_ACT_HANDLED)
2392 } while (count < 30);
2394 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2395 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2403 EXPORT_SYMBOL(drm_dp_check_act_status);
2406 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2407 * @clock: dot clock for the mode
2408 * @bpp: bpp for the mode.
2410 * This uses the formula in the spec to calculate the PBN value for a mode.
2412 int drm_dp_calc_pbn_mode(int clock, int bpp)
2417 fixed20_12 margin, tmp;
2420 pix_bw.full = dfixed_const(clock);
2421 fbpp.full = dfixed_const(bpp);
2422 tmp.full = dfixed_const(8);
2423 fbpp.full = dfixed_div(fbpp, tmp);
2425 result.full = dfixed_mul(pix_bw, fbpp);
2426 margin.full = dfixed_const(54);
2427 tmp.full = dfixed_const(64);
2428 margin.full = dfixed_div(margin, tmp);
2429 result.full = dfixed_div(result, margin);
2431 margin.full = dfixed_const(1006);
2432 tmp.full = dfixed_const(1000);
2433 margin.full = dfixed_div(margin, tmp);
2434 result.full = dfixed_mul(result, margin);
2436 result.full = dfixed_div(result, tmp);
2437 result.full = dfixed_ceil(result);
2438 res = dfixed_trunc(result);
2441 EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2443 static int test_calc_pbn_mode(void)
2446 ret = drm_dp_calc_pbn_mode(154000, 30);
2449 ret = drm_dp_calc_pbn_mode(234000, 30);
2455 /* we want to kick the TX after we've ack the up/down IRQs. */
2456 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2458 queue_work(system_long_wq, &mgr->tx_work);
2461 static void drm_dp_mst_dump_mstb(struct seq_file *m,
2462 struct drm_dp_mst_branch *mstb)
2464 struct drm_dp_mst_port *port;
2465 int tabs = mstb->lct;
2469 for (i = 0; i < tabs; i++)
2473 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2474 list_for_each_entry(port, &mstb->ports, next) {
2475 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2477 drm_dp_mst_dump_mstb(m, port->mstb);
2481 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2486 for (i = 0; i < 4; i++) {
2487 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2497 * drm_dp_mst_dump_topology(): dump topology to seq file.
2498 * @m: seq_file to dump output to
2499 * @mgr: manager to dump current topology for.
2501 * helper to dump MST topology to a seq file for debugfs.
2503 void drm_dp_mst_dump_topology(struct seq_file *m,
2504 struct drm_dp_mst_topology_mgr *mgr)
2507 struct drm_dp_mst_port *port;
2508 mutex_lock(&mgr->lock);
2509 if (mgr->mst_primary)
2510 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2513 mutex_unlock(&mgr->lock);
2515 mutex_lock(&mgr->payload_lock);
2516 seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask);
2518 for (i = 0; i < mgr->max_payloads; i++) {
2519 if (mgr->proposed_vcpis[i]) {
2520 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2521 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2523 seq_printf(m, "vcpi %d:unsed\n", i);
2525 for (i = 0; i < mgr->max_payloads; i++) {
2526 seq_printf(m, "payload %d: %d, %d, %d\n",
2528 mgr->payloads[i].payload_state,
2529 mgr->payloads[i].start_slot,
2530 mgr->payloads[i].num_slots);
2534 mutex_unlock(&mgr->payload_lock);
2536 mutex_lock(&mgr->lock);
2537 if (mgr->mst_primary) {
2541 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2542 seq_printf(m, "dpcd: ");
2543 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2544 seq_printf(m, "%02x ", buf[i]);
2545 seq_printf(m, "\n");
2546 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2547 seq_printf(m, "faux/mst: ");
2548 for (i = 0; i < 2; i++)
2549 seq_printf(m, "%02x ", buf[i]);
2550 seq_printf(m, "\n");
2551 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2552 seq_printf(m, "mst ctrl: ");
2553 for (i = 0; i < 1; i++)
2554 seq_printf(m, "%02x ", buf[i]);
2555 seq_printf(m, "\n");
2557 bret = dump_dp_payload_table(mgr, buf);
2559 seq_printf(m, "payload table: ");
2560 for (i = 0; i < 63; i++)
2561 seq_printf(m, "%02x ", buf[i]);
2562 seq_printf(m, "\n");
2567 mutex_unlock(&mgr->lock);
2570 EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2572 static void drm_dp_tx_work(struct work_struct *work)
2574 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2576 mutex_lock(&mgr->qlock);
2577 if (mgr->tx_down_in_progress)
2578 process_single_down_tx_qlock(mgr);
2579 mutex_unlock(&mgr->qlock);
2583 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2584 * @mgr: manager struct to initialise
2585 * @dev: device providing this structure - for i2c addition.
2586 * @aux: DP helper aux channel to talk to this device
2587 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2588 * @max_payloads: maximum number of payloads this GPU can source
2589 * @conn_base_id: the connector object ID the MST device is connected to.
2591 * Return 0 for success, or negative error code on failure
2593 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2594 struct device *dev, struct drm_dp_aux *aux,
2595 int max_dpcd_transaction_bytes,
2596 int max_payloads, int conn_base_id)
2598 mutex_init(&mgr->lock);
2599 mutex_init(&mgr->qlock);
2600 mutex_init(&mgr->payload_lock);
2601 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2602 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2603 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2604 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2605 init_waitqueue_head(&mgr->tx_waitq);
2608 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2609 mgr->max_payloads = max_payloads;
2610 mgr->conn_base_id = conn_base_id;
2611 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2614 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2615 if (!mgr->proposed_vcpis)
2617 set_bit(0, &mgr->payload_mask);
2618 test_calc_pbn_mode();
2621 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2624 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2625 * @mgr: manager to destroy
2627 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2629 mutex_lock(&mgr->payload_lock);
2630 kfree(mgr->payloads);
2631 mgr->payloads = NULL;
2632 kfree(mgr->proposed_vcpis);
2633 mgr->proposed_vcpis = NULL;
2634 mutex_unlock(&mgr->payload_lock);
2638 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2641 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2644 struct drm_dp_aux *aux = adapter->algo_data;
2645 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2646 struct drm_dp_mst_branch *mstb;
2647 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2649 bool reading = false;
2650 struct drm_dp_sideband_msg_req_body msg;
2651 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2654 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2658 /* construct i2c msg */
2659 /* see if last msg is a read */
2660 if (msgs[num - 1].flags & I2C_M_RD)
2664 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2669 msg.req_type = DP_REMOTE_I2C_READ;
2670 msg.u.i2c_read.num_transactions = num - 1;
2671 msg.u.i2c_read.port_number = port->port_num;
2672 for (i = 0; i < num - 1; i++) {
2673 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2674 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2675 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2677 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2678 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2680 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2687 drm_dp_encode_sideband_req(&msg, txmsg);
2689 drm_dp_queue_down_tx(mgr, txmsg);
2691 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2694 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2698 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2702 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2707 drm_dp_put_mst_branch_device(mstb);
2711 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2713 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2714 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2715 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2716 I2C_FUNC_10BIT_ADDR;
2719 static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2720 .functionality = drm_dp_mst_i2c_functionality,
2721 .master_xfer = drm_dp_mst_i2c_xfer,
2725 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2726 * @aux: DisplayPort AUX channel
2728 * Returns 0 on success or a negative error code on failure.
2730 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2732 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2733 aux->ddc.algo_data = aux;
2734 aux->ddc.retries = 3;
2736 aux->ddc.class = I2C_CLASS_DDC;
2737 aux->ddc.owner = THIS_MODULE;
2738 aux->ddc.dev.parent = aux->dev;
2739 aux->ddc.dev.of_node = aux->dev->of_node;
2741 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2742 sizeof(aux->ddc.name));
2744 return i2c_add_adapter(&aux->ddc);
2748 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2749 * @aux: DisplayPort AUX channel
2751 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2753 i2c_del_adapter(&aux->ddc);