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>
34 #include <drm/drm_atomic.h>
35 #include <drm/drm_atomic_helper.h>
40 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
41 * protocol. The helpers contain a topology manager and bandwidth manager.
42 * The helpers encapsulate the sending and received of sideband msgs.
44 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
46 static int test_calc_pbn_mode(void);
48 static void drm_dp_put_port(struct drm_dp_mst_port *port);
50 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
52 struct drm_dp_payload *payload);
54 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
55 struct drm_dp_mst_port *port,
56 int offset, int size, u8 *bytes);
58 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
59 struct drm_dp_mst_branch *mstb);
60 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
61 struct drm_dp_mst_branch *mstb,
62 struct drm_dp_mst_port *port);
63 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
66 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
67 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
68 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
69 /* sideband msg handling */
70 static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
75 int number_of_bits = num_nibbles * 4;
78 while (number_of_bits != 0) {
81 remainder |= (data[array_index] & bitmask) >> bitshift;
89 if ((remainder & 0x10) == 0x10)
94 while (number_of_bits != 0) {
97 if ((remainder & 0x10) != 0)
104 static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
109 int number_of_bits = number_of_bytes * 8;
112 while (number_of_bits != 0) {
115 remainder |= (data[array_index] & bitmask) >> bitshift;
123 if ((remainder & 0x100) == 0x100)
128 while (number_of_bits != 0) {
131 if ((remainder & 0x100) != 0)
135 return remainder & 0xff;
137 static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
140 size += (hdr->lct / 2);
144 static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
150 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
151 for (i = 0; i < (hdr->lct / 2); i++)
152 buf[idx++] = hdr->rad[i];
153 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
154 (hdr->msg_len & 0x3f);
155 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
157 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
158 buf[idx - 1] |= (crc4 & 0xf);
163 static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
164 u8 *buf, int buflen, u8 *hdrlen)
173 len += ((buf[0] & 0xf0) >> 4) / 2;
176 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
178 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
179 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
183 hdr->lct = (buf[0] & 0xf0) >> 4;
184 hdr->lcr = (buf[0] & 0xf);
186 for (i = 0; i < (hdr->lct / 2); i++)
187 hdr->rad[i] = buf[idx++];
188 hdr->broadcast = (buf[idx] >> 7) & 0x1;
189 hdr->path_msg = (buf[idx] >> 6) & 0x1;
190 hdr->msg_len = buf[idx] & 0x3f;
192 hdr->somt = (buf[idx] >> 7) & 0x1;
193 hdr->eomt = (buf[idx] >> 6) & 0x1;
194 hdr->seqno = (buf[idx] >> 4) & 0x1;
200 static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
201 struct drm_dp_sideband_msg_tx *raw)
206 buf[idx++] = req->req_type & 0x7f;
208 switch (req->req_type) {
209 case DP_ENUM_PATH_RESOURCES:
210 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
213 case DP_ALLOCATE_PAYLOAD:
214 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
215 (req->u.allocate_payload.number_sdp_streams & 0xf);
217 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
219 buf[idx] = (req->u.allocate_payload.pbn >> 8);
221 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
223 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
224 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
225 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
228 if (req->u.allocate_payload.number_sdp_streams & 1) {
229 i = req->u.allocate_payload.number_sdp_streams - 1;
230 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
234 case DP_QUERY_PAYLOAD:
235 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
237 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
240 case DP_REMOTE_DPCD_READ:
241 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
242 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
246 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
248 buf[idx] = (req->u.dpcd_read.num_bytes);
252 case DP_REMOTE_DPCD_WRITE:
253 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
254 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
258 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
260 buf[idx] = (req->u.dpcd_write.num_bytes);
262 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
263 idx += req->u.dpcd_write.num_bytes;
265 case DP_REMOTE_I2C_READ:
266 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
267 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
269 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
270 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
272 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
274 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
275 idx += req->u.i2c_read.transactions[i].num_bytes;
277 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
278 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
281 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
283 buf[idx] = (req->u.i2c_read.num_bytes_read);
287 case DP_REMOTE_I2C_WRITE:
288 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
290 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
292 buf[idx] = (req->u.i2c_write.num_bytes);
294 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
295 idx += req->u.i2c_write.num_bytes;
298 case DP_POWER_DOWN_PHY:
299 case DP_POWER_UP_PHY:
300 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
307 static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
310 crc4 = drm_dp_msg_data_crc4(msg, len);
314 static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
315 struct drm_dp_sideband_msg_tx *raw)
320 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
325 /* this adds a chunk of msg to the builder to get the final msg */
326 static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
327 u8 *replybuf, u8 replybuflen, bool hdr)
334 struct drm_dp_sideband_msg_hdr recv_hdr;
335 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
337 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
342 * ignore out-of-order messages or messages that are part of a
345 if (!recv_hdr.somt && !msg->have_somt)
348 /* get length contained in this portion */
349 msg->curchunk_len = recv_hdr.msg_len;
350 msg->curchunk_hdrlen = hdrlen;
352 /* we have already gotten an somt - don't bother parsing */
353 if (recv_hdr.somt && msg->have_somt)
357 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
358 msg->have_somt = true;
361 msg->have_eomt = true;
363 /* copy the bytes for the remainder of this header chunk */
364 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
365 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
367 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
368 msg->curchunk_idx += replybuflen;
371 if (msg->curchunk_idx >= msg->curchunk_len) {
373 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
374 /* copy chunk into bigger msg */
375 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
376 msg->curlen += msg->curchunk_len - 1;
381 static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
382 struct drm_dp_sideband_msg_reply_body *repmsg)
386 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
388 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
390 if (idx > raw->curlen)
392 for (i = 0; i < repmsg->u.link_addr.nports; i++) {
393 if (raw->msg[idx] & 0x80)
394 repmsg->u.link_addr.ports[i].input_port = 1;
396 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
397 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
400 if (idx > raw->curlen)
402 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
403 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
404 if (repmsg->u.link_addr.ports[i].input_port == 0)
405 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
407 if (idx > raw->curlen)
409 if (repmsg->u.link_addr.ports[i].input_port == 0) {
410 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
412 if (idx > raw->curlen)
414 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
416 if (idx > raw->curlen)
418 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
419 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
423 if (idx > raw->curlen)
429 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
433 static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
434 struct drm_dp_sideband_msg_reply_body *repmsg)
437 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
439 if (idx > raw->curlen)
441 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
442 if (idx > raw->curlen)
445 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
448 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
452 static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
453 struct drm_dp_sideband_msg_reply_body *repmsg)
456 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
458 if (idx > raw->curlen)
462 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
466 static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
467 struct drm_dp_sideband_msg_reply_body *repmsg)
471 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
473 if (idx > raw->curlen)
475 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
478 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
481 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
485 static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
486 struct drm_dp_sideband_msg_reply_body *repmsg)
489 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
491 if (idx > raw->curlen)
493 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
495 if (idx > raw->curlen)
497 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
499 if (idx > raw->curlen)
503 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
507 static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
508 struct drm_dp_sideband_msg_reply_body *repmsg)
511 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
513 if (idx > raw->curlen)
515 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
517 if (idx > raw->curlen)
519 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
521 if (idx > raw->curlen)
525 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
529 static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
530 struct drm_dp_sideband_msg_reply_body *repmsg)
533 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
535 if (idx > raw->curlen)
537 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
539 if (idx > raw->curlen)
543 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
547 static bool drm_dp_sideband_parse_power_updown_phy_ack(struct drm_dp_sideband_msg_rx *raw,
548 struct drm_dp_sideband_msg_reply_body *repmsg)
552 repmsg->u.port_number.port_number = (raw->msg[idx] >> 4) & 0xf;
554 if (idx > raw->curlen) {
555 DRM_DEBUG_KMS("power up/down phy parse length fail %d %d\n",
562 static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
563 struct drm_dp_sideband_msg_reply_body *msg)
565 memset(msg, 0, sizeof(*msg));
566 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
567 msg->req_type = (raw->msg[0] & 0x7f);
569 if (msg->reply_type) {
570 memcpy(msg->u.nak.guid, &raw->msg[1], 16);
571 msg->u.nak.reason = raw->msg[17];
572 msg->u.nak.nak_data = raw->msg[18];
576 switch (msg->req_type) {
577 case DP_LINK_ADDRESS:
578 return drm_dp_sideband_parse_link_address(raw, msg);
579 case DP_QUERY_PAYLOAD:
580 return drm_dp_sideband_parse_query_payload_ack(raw, msg);
581 case DP_REMOTE_DPCD_READ:
582 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
583 case DP_REMOTE_DPCD_WRITE:
584 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
585 case DP_REMOTE_I2C_READ:
586 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
587 case DP_ENUM_PATH_RESOURCES:
588 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
589 case DP_ALLOCATE_PAYLOAD:
590 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
591 case DP_POWER_DOWN_PHY:
592 case DP_POWER_UP_PHY:
593 return drm_dp_sideband_parse_power_updown_phy_ack(raw, msg);
595 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
600 static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
601 struct drm_dp_sideband_msg_req_body *msg)
605 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
607 if (idx > raw->curlen)
610 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
612 if (idx > raw->curlen)
615 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
616 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
617 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
618 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
619 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
623 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
627 static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
628 struct drm_dp_sideband_msg_req_body *msg)
632 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
634 if (idx > raw->curlen)
637 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
639 if (idx > raw->curlen)
642 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
646 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
650 static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
651 struct drm_dp_sideband_msg_req_body *msg)
653 memset(msg, 0, sizeof(*msg));
654 msg->req_type = (raw->msg[0] & 0x7f);
656 switch (msg->req_type) {
657 case DP_CONNECTION_STATUS_NOTIFY:
658 return drm_dp_sideband_parse_connection_status_notify(raw, msg);
659 case DP_RESOURCE_STATUS_NOTIFY:
660 return drm_dp_sideband_parse_resource_status_notify(raw, msg);
662 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
667 static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
669 struct drm_dp_sideband_msg_req_body req;
671 req.req_type = DP_REMOTE_DPCD_WRITE;
672 req.u.dpcd_write.port_number = port_num;
673 req.u.dpcd_write.dpcd_address = offset;
674 req.u.dpcd_write.num_bytes = num_bytes;
675 req.u.dpcd_write.bytes = bytes;
676 drm_dp_encode_sideband_req(&req, msg);
681 static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
683 struct drm_dp_sideband_msg_req_body req;
685 req.req_type = DP_LINK_ADDRESS;
686 drm_dp_encode_sideband_req(&req, msg);
690 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
692 struct drm_dp_sideband_msg_req_body req;
694 req.req_type = DP_ENUM_PATH_RESOURCES;
695 req.u.port_num.port_number = port_num;
696 drm_dp_encode_sideband_req(&req, msg);
697 msg->path_msg = true;
701 static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
702 u8 vcpi, uint16_t pbn,
703 u8 number_sdp_streams,
706 struct drm_dp_sideband_msg_req_body req;
707 memset(&req, 0, sizeof(req));
708 req.req_type = DP_ALLOCATE_PAYLOAD;
709 req.u.allocate_payload.port_number = port_num;
710 req.u.allocate_payload.vcpi = vcpi;
711 req.u.allocate_payload.pbn = pbn;
712 req.u.allocate_payload.number_sdp_streams = number_sdp_streams;
713 memcpy(req.u.allocate_payload.sdp_stream_sink, sdp_stream_sink,
715 drm_dp_encode_sideband_req(&req, msg);
716 msg->path_msg = true;
720 static int build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg,
721 int port_num, bool power_up)
723 struct drm_dp_sideband_msg_req_body req;
726 req.req_type = DP_POWER_UP_PHY;
728 req.req_type = DP_POWER_DOWN_PHY;
730 req.u.port_num.port_number = port_num;
731 drm_dp_encode_sideband_req(&req, msg);
732 msg->path_msg = true;
736 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
737 struct drm_dp_vcpi *vcpi)
741 mutex_lock(&mgr->payload_lock);
742 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1);
743 if (ret > mgr->max_payloads) {
745 DRM_DEBUG_KMS("out of payload ids %d\n", ret);
749 vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1);
750 if (vcpi_ret > mgr->max_payloads) {
752 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret);
756 set_bit(ret, &mgr->payload_mask);
757 set_bit(vcpi_ret, &mgr->vcpi_mask);
758 vcpi->vcpi = vcpi_ret + 1;
759 mgr->proposed_vcpis[ret - 1] = vcpi;
761 mutex_unlock(&mgr->payload_lock);
765 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
772 mutex_lock(&mgr->payload_lock);
773 DRM_DEBUG_KMS("putting payload %d\n", vcpi);
774 clear_bit(vcpi - 1, &mgr->vcpi_mask);
776 for (i = 0; i < mgr->max_payloads; i++) {
777 if (mgr->proposed_vcpis[i])
778 if (mgr->proposed_vcpis[i]->vcpi == vcpi) {
779 mgr->proposed_vcpis[i] = NULL;
780 clear_bit(i + 1, &mgr->payload_mask);
783 mutex_unlock(&mgr->payload_lock);
786 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
787 struct drm_dp_sideband_msg_tx *txmsg)
792 * All updates to txmsg->state are protected by mgr->qlock, and the two
793 * cases we check here are terminal states. For those the barriers
794 * provided by the wake_up/wait_event pair are enough.
796 state = READ_ONCE(txmsg->state);
797 return (state == DRM_DP_SIDEBAND_TX_RX ||
798 state == DRM_DP_SIDEBAND_TX_TIMEOUT);
801 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
802 struct drm_dp_sideband_msg_tx *txmsg)
804 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
807 ret = wait_event_timeout(mgr->tx_waitq,
808 check_txmsg_state(mgr, txmsg),
810 mutex_lock(&mstb->mgr->qlock);
812 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
817 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
819 /* dump some state */
823 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
824 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
825 list_del(&txmsg->next);
828 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
829 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
830 mstb->tx_slots[txmsg->seqno] = NULL;
834 mutex_unlock(&mgr->qlock);
839 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
841 struct drm_dp_mst_branch *mstb;
843 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
849 memcpy(mstb->rad, rad, lct / 2);
850 INIT_LIST_HEAD(&mstb->ports);
851 kref_init(&mstb->kref);
855 static void drm_dp_free_mst_port(struct kref *kref);
857 static void drm_dp_free_mst_branch_device(struct kref *kref)
859 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
860 if (mstb->port_parent) {
861 if (list_empty(&mstb->port_parent->next))
862 kref_put(&mstb->port_parent->kref, drm_dp_free_mst_port);
867 static void drm_dp_destroy_mst_branch_device(struct kref *kref)
869 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
870 struct drm_dp_mst_port *port, *tmp;
871 bool wake_tx = false;
874 * init kref again to be used by ports to remove mst branch when it is
879 if (mstb->port_parent && list_empty(&mstb->port_parent->next))
880 kref_get(&mstb->port_parent->kref);
883 * destroy all ports - don't need lock
884 * as there are no more references to the mst branch
885 * device at this point.
887 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
888 list_del(&port->next);
889 drm_dp_put_port(port);
892 /* drop any tx slots msg */
893 mutex_lock(&mstb->mgr->qlock);
894 if (mstb->tx_slots[0]) {
895 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
896 mstb->tx_slots[0] = NULL;
899 if (mstb->tx_slots[1]) {
900 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
901 mstb->tx_slots[1] = NULL;
904 mutex_unlock(&mstb->mgr->qlock);
907 wake_up_all(&mstb->mgr->tx_waitq);
909 kref_put(kref, drm_dp_free_mst_branch_device);
912 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
914 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
918 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
920 struct drm_dp_mst_branch *mstb;
923 case DP_PEER_DEVICE_DP_LEGACY_CONV:
924 case DP_PEER_DEVICE_SST_SINK:
925 /* remove i2c over sideband */
926 drm_dp_mst_unregister_i2c_bus(&port->aux);
928 case DP_PEER_DEVICE_MST_BRANCHING:
931 drm_dp_put_mst_branch_device(mstb);
936 static void drm_dp_destroy_port(struct kref *kref)
938 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
939 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
942 port->vcpi.num_slots = 0;
944 kfree(port->cached_edid);
947 * The only time we don't have a connector
948 * on an output port is if the connector init
951 if (port->connector) {
952 /* we can't destroy the connector here, as
953 * we might be holding the mode_config.mutex
954 * from an EDID retrieval */
956 mutex_lock(&mgr->destroy_connector_lock);
957 kref_get(&port->parent->kref);
958 list_add(&port->next, &mgr->destroy_connector_list);
959 mutex_unlock(&mgr->destroy_connector_lock);
960 schedule_work(&mgr->destroy_connector_work);
963 /* no need to clean up vcpi
964 * as if we have no connector we never setup a vcpi */
965 drm_dp_port_teardown_pdt(port, port->pdt);
966 port->pdt = DP_PEER_DEVICE_NONE;
971 static void drm_dp_put_port(struct drm_dp_mst_port *port)
973 kref_put(&port->kref, drm_dp_destroy_port);
976 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)
978 struct drm_dp_mst_port *port;
979 struct drm_dp_mst_branch *rmstb;
980 if (to_find == mstb) {
981 kref_get(&mstb->kref);
984 list_for_each_entry(port, &mstb->ports, next) {
986 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
994 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)
996 struct drm_dp_mst_branch *rmstb = NULL;
997 mutex_lock(&mgr->lock);
998 if (mgr->mst_primary)
999 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
1000 mutex_unlock(&mgr->lock);
1004 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)
1006 struct drm_dp_mst_port *port, *mport;
1008 list_for_each_entry(port, &mstb->ports, next) {
1009 if (port == to_find) {
1010 kref_get(&port->kref);
1014 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
1022 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)
1024 struct drm_dp_mst_port *rport = NULL;
1025 mutex_lock(&mgr->lock);
1026 if (mgr->mst_primary)
1027 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
1028 mutex_unlock(&mgr->lock);
1032 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
1034 struct drm_dp_mst_port *port;
1036 list_for_each_entry(port, &mstb->ports, next) {
1037 if (port->port_num == port_num) {
1038 kref_get(&port->kref);
1047 * calculate a new RAD for this MST branch device
1048 * if parent has an LCT of 2 then it has 1 nibble of RAD,
1049 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
1051 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
1054 int parent_lct = port->parent->lct;
1056 int idx = (parent_lct - 1) / 2;
1057 if (parent_lct > 1) {
1058 memcpy(rad, port->parent->rad, idx + 1);
1059 shift = (parent_lct % 2) ? 4 : 0;
1063 rad[idx] |= port->port_num << shift;
1064 return parent_lct + 1;
1068 * return sends link address for new mstb
1070 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
1074 bool send_link = false;
1075 switch (port->pdt) {
1076 case DP_PEER_DEVICE_DP_LEGACY_CONV:
1077 case DP_PEER_DEVICE_SST_SINK:
1078 /* add i2c over sideband */
1079 ret = drm_dp_mst_register_i2c_bus(&port->aux);
1081 case DP_PEER_DEVICE_MST_BRANCHING:
1082 lct = drm_dp_calculate_rad(port, rad);
1084 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
1085 port->mstb->mgr = port->mgr;
1086 port->mstb->port_parent = port;
1094 static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid)
1098 memcpy(mstb->guid, guid, 16);
1100 if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) {
1101 if (mstb->port_parent) {
1102 ret = drm_dp_send_dpcd_write(
1110 ret = drm_dp_dpcd_write(
1119 static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
1122 size_t proppath_size)
1126 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
1127 for (i = 0; i < (mstb->lct - 1); i++) {
1128 int shift = (i % 2) ? 0 : 4;
1129 int port_num = (mstb->rad[i / 2] >> shift) & 0xf;
1130 snprintf(temp, sizeof(temp), "-%d", port_num);
1131 strlcat(proppath, temp, proppath_size);
1133 snprintf(temp, sizeof(temp), "-%d", pnum);
1134 strlcat(proppath, temp, proppath_size);
1137 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1138 struct drm_device *dev,
1139 struct drm_dp_link_addr_reply_port *port_msg)
1141 struct drm_dp_mst_port *port;
1143 bool created = false;
1146 port = drm_dp_get_port(mstb, port_msg->port_number);
1148 port = kzalloc(sizeof(*port), GFP_KERNEL);
1151 kref_init(&port->kref);
1152 port->parent = mstb;
1153 port->port_num = port_msg->port_number;
1154 port->mgr = mstb->mgr;
1155 port->aux.name = "DPMST";
1156 port->aux.dev = dev->dev;
1159 old_pdt = port->pdt;
1160 old_ddps = port->ddps;
1163 port->pdt = port_msg->peer_device_type;
1164 port->input = port_msg->input_port;
1165 port->mcs = port_msg->mcs;
1166 port->ddps = port_msg->ddps;
1167 port->ldps = port_msg->legacy_device_plug_status;
1168 port->dpcd_rev = port_msg->dpcd_revision;
1169 port->num_sdp_streams = port_msg->num_sdp_streams;
1170 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1172 /* manage mstb port lists with mgr lock - take a reference
1175 mutex_lock(&mstb->mgr->lock);
1176 kref_get(&port->kref);
1177 list_add(&port->next, &mstb->ports);
1178 mutex_unlock(&mstb->mgr->lock);
1181 if (old_ddps != port->ddps) {
1184 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1186 port->available_pbn = 0;
1190 if (old_pdt != port->pdt && !port->input) {
1191 drm_dp_port_teardown_pdt(port, old_pdt);
1193 ret = drm_dp_port_setup_pdt(port);
1195 drm_dp_send_link_address(mstb->mgr, port->mstb);
1198 if (created && !port->input) {
1201 build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath));
1202 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1203 if (!port->connector) {
1204 /* remove it from the port list */
1205 mutex_lock(&mstb->mgr->lock);
1206 list_del(&port->next);
1207 mutex_unlock(&mstb->mgr->lock);
1208 /* drop port list reference */
1209 drm_dp_put_port(port);
1212 if ((port->pdt == DP_PEER_DEVICE_DP_LEGACY_CONV ||
1213 port->pdt == DP_PEER_DEVICE_SST_SINK) &&
1214 port->port_num >= DP_MST_LOGICAL_PORT_0) {
1215 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
1216 drm_mode_connector_set_tile_property(port->connector);
1218 (*mstb->mgr->cbs->register_connector)(port->connector);
1222 /* put reference to this port */
1223 drm_dp_put_port(port);
1226 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1227 struct drm_dp_connection_status_notify *conn_stat)
1229 struct drm_dp_mst_port *port;
1232 bool dowork = false;
1233 port = drm_dp_get_port(mstb, conn_stat->port_number);
1237 old_ddps = port->ddps;
1238 old_pdt = port->pdt;
1239 port->pdt = conn_stat->peer_device_type;
1240 port->mcs = conn_stat->message_capability_status;
1241 port->ldps = conn_stat->legacy_device_plug_status;
1242 port->ddps = conn_stat->displayport_device_plug_status;
1244 if (old_ddps != port->ddps) {
1248 port->available_pbn = 0;
1251 if (old_pdt != port->pdt && !port->input) {
1252 drm_dp_port_teardown_pdt(port, old_pdt);
1254 if (drm_dp_port_setup_pdt(port))
1258 drm_dp_put_port(port);
1260 queue_work(system_long_wq, &mstb->mgr->work);
1264 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1267 struct drm_dp_mst_branch *mstb;
1268 struct drm_dp_mst_port *port;
1270 /* find the port by iterating down */
1272 mutex_lock(&mgr->lock);
1273 mstb = mgr->mst_primary;
1275 for (i = 0; i < lct - 1; i++) {
1276 int shift = (i % 2) ? 0 : 4;
1277 int port_num = (rad[i / 2] >> shift) & 0xf;
1279 list_for_each_entry(port, &mstb->ports, next) {
1280 if (port->port_num == port_num) {
1283 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1291 kref_get(&mstb->kref);
1293 mutex_unlock(&mgr->lock);
1297 static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper(
1298 struct drm_dp_mst_branch *mstb,
1301 struct drm_dp_mst_branch *found_mstb;
1302 struct drm_dp_mst_port *port;
1304 if (memcmp(mstb->guid, guid, 16) == 0)
1308 list_for_each_entry(port, &mstb->ports, next) {
1312 found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid);
1321 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device_by_guid(
1322 struct drm_dp_mst_topology_mgr *mgr,
1325 struct drm_dp_mst_branch *mstb;
1327 /* find the port by iterating down */
1328 mutex_lock(&mgr->lock);
1330 mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid);
1333 kref_get(&mstb->kref);
1335 mutex_unlock(&mgr->lock);
1339 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1340 struct drm_dp_mst_branch *mstb)
1342 struct drm_dp_mst_port *port;
1343 struct drm_dp_mst_branch *mstb_child;
1344 if (!mstb->link_address_sent)
1345 drm_dp_send_link_address(mgr, mstb);
1347 list_for_each_entry(port, &mstb->ports, next) {
1354 if (!port->available_pbn)
1355 drm_dp_send_enum_path_resources(mgr, mstb, port);
1358 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
1360 drm_dp_check_and_send_link_address(mgr, mstb_child);
1361 drm_dp_put_mst_branch_device(mstb_child);
1367 static void drm_dp_mst_link_probe_work(struct work_struct *work)
1369 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1370 struct drm_dp_mst_branch *mstb;
1372 mutex_lock(&mgr->lock);
1373 mstb = mgr->mst_primary;
1375 kref_get(&mstb->kref);
1377 mutex_unlock(&mgr->lock);
1379 drm_dp_check_and_send_link_address(mgr, mstb);
1380 drm_dp_put_mst_branch_device(mstb);
1384 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1389 if (memchr_inv(guid, 0, 16))
1392 salt = get_jiffies_64();
1394 memcpy(&guid[0], &salt, sizeof(u64));
1395 memcpy(&guid[8], &salt, sizeof(u64));
1401 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1403 struct drm_dp_sideband_msg_req_body req;
1405 req.req_type = DP_REMOTE_DPCD_READ;
1406 req.u.dpcd_read.port_number = port_num;
1407 req.u.dpcd_read.dpcd_address = offset;
1408 req.u.dpcd_read.num_bytes = num_bytes;
1409 drm_dp_encode_sideband_req(&req, msg);
1415 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1416 bool up, u8 *msg, int len)
1419 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1420 int tosend, total, offset;
1427 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1429 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1432 if (ret != tosend) {
1433 if (ret == -EIO && retries < 5) {
1437 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1443 } while (total > 0);
1447 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1448 struct drm_dp_sideband_msg_tx *txmsg)
1450 struct drm_dp_mst_branch *mstb = txmsg->dst;
1453 /* both msg slots are full */
1454 if (txmsg->seqno == -1) {
1455 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1456 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1459 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1460 txmsg->seqno = mstb->last_seqno;
1461 mstb->last_seqno ^= 1;
1462 } else if (mstb->tx_slots[0] == NULL)
1466 mstb->tx_slots[txmsg->seqno] = txmsg;
1469 req_type = txmsg->msg[0] & 0x7f;
1470 if (req_type == DP_CONNECTION_STATUS_NOTIFY ||
1471 req_type == DP_RESOURCE_STATUS_NOTIFY)
1475 hdr->path_msg = txmsg->path_msg;
1476 hdr->lct = mstb->lct;
1477 hdr->lcr = mstb->lct - 1;
1479 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1480 hdr->seqno = txmsg->seqno;
1484 * process a single block of the next message in the sideband queue
1486 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1487 struct drm_dp_sideband_msg_tx *txmsg,
1491 struct drm_dp_sideband_msg_hdr hdr;
1492 int len, space, idx, tosend;
1495 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1497 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1499 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1502 /* make hdr from dst mst - for replies use seqno
1503 otherwise assign one */
1504 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1508 /* amount left to send in this message */
1509 len = txmsg->cur_len - txmsg->cur_offset;
1511 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1512 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1514 tosend = min(len, space);
1515 if (len == txmsg->cur_len)
1521 hdr.msg_len = tosend + 1;
1522 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1523 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1524 /* add crc at end */
1525 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1528 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1530 DRM_DEBUG_KMS("sideband msg failed to send\n");
1534 txmsg->cur_offset += tosend;
1535 if (txmsg->cur_offset == txmsg->cur_len) {
1536 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1542 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1544 struct drm_dp_sideband_msg_tx *txmsg;
1547 WARN_ON(!mutex_is_locked(&mgr->qlock));
1549 /* construct a chunk from the first msg in the tx_msg queue */
1550 if (list_empty(&mgr->tx_msg_downq))
1553 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1554 ret = process_single_tx_qlock(mgr, txmsg, false);
1556 /* txmsg is sent it should be in the slots now */
1557 list_del(&txmsg->next);
1559 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1560 list_del(&txmsg->next);
1561 if (txmsg->seqno != -1)
1562 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1563 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1564 wake_up_all(&mgr->tx_waitq);
1568 /* called holding qlock */
1569 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1570 struct drm_dp_sideband_msg_tx *txmsg)
1574 /* construct a chunk from the first msg in the tx_msg queue */
1575 ret = process_single_tx_qlock(mgr, txmsg, true);
1578 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1580 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1583 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1584 struct drm_dp_sideband_msg_tx *txmsg)
1586 mutex_lock(&mgr->qlock);
1587 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1588 if (list_is_singular(&mgr->tx_msg_downq))
1589 process_single_down_tx_qlock(mgr);
1590 mutex_unlock(&mgr->qlock);
1593 static void drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1594 struct drm_dp_mst_branch *mstb)
1597 struct drm_dp_sideband_msg_tx *txmsg;
1600 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1605 len = build_link_address(txmsg);
1607 mstb->link_address_sent = true;
1608 drm_dp_queue_down_tx(mgr, txmsg);
1610 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1614 if (txmsg->reply.reply_type == 1)
1615 DRM_DEBUG_KMS("link address nak received\n");
1617 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1618 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1619 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,
1620 txmsg->reply.u.link_addr.ports[i].input_port,
1621 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1622 txmsg->reply.u.link_addr.ports[i].port_number,
1623 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1624 txmsg->reply.u.link_addr.ports[i].mcs,
1625 txmsg->reply.u.link_addr.ports[i].ddps,
1626 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1627 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1628 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1631 drm_dp_check_mstb_guid(mstb, txmsg->reply.u.link_addr.guid);
1633 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1634 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1636 (*mgr->cbs->hotplug)(mgr);
1639 mstb->link_address_sent = false;
1640 DRM_DEBUG_KMS("link address failed %d\n", ret);
1646 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1647 struct drm_dp_mst_branch *mstb,
1648 struct drm_dp_mst_port *port)
1651 struct drm_dp_sideband_msg_tx *txmsg;
1654 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1659 len = build_enum_path_resources(txmsg, port->port_num);
1661 drm_dp_queue_down_tx(mgr, txmsg);
1663 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1665 if (txmsg->reply.reply_type == 1)
1666 DRM_DEBUG_KMS("enum path resources nak received\n");
1668 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1669 DRM_ERROR("got incorrect port in response\n");
1670 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,
1671 txmsg->reply.u.path_resources.avail_payload_bw_number);
1672 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1680 static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb)
1682 if (!mstb->port_parent)
1685 if (mstb->port_parent->mstb != mstb)
1686 return mstb->port_parent;
1688 return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent);
1691 static struct drm_dp_mst_branch *drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr,
1692 struct drm_dp_mst_branch *mstb,
1695 struct drm_dp_mst_branch *rmstb = NULL;
1696 struct drm_dp_mst_port *found_port;
1697 mutex_lock(&mgr->lock);
1698 if (mgr->mst_primary) {
1699 found_port = drm_dp_get_last_connected_port_to_mstb(mstb);
1702 rmstb = found_port->parent;
1703 kref_get(&rmstb->kref);
1704 *port_num = found_port->port_num;
1707 mutex_unlock(&mgr->lock);
1711 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1712 struct drm_dp_mst_port *port,
1716 struct drm_dp_sideband_msg_tx *txmsg;
1717 struct drm_dp_mst_branch *mstb;
1718 int len, ret, port_num;
1719 u8 sinks[DRM_DP_MAX_SDP_STREAMS];
1722 port = drm_dp_get_validated_port_ref(mgr, port);
1726 port_num = port->port_num;
1727 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1729 mstb = drm_dp_get_last_connected_port_and_mstb(mgr, port->parent, &port_num);
1732 drm_dp_put_port(port);
1737 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1743 for (i = 0; i < port->num_sdp_streams; i++)
1747 len = build_allocate_payload(txmsg, port_num,
1749 pbn, port->num_sdp_streams, sinks);
1751 drm_dp_queue_down_tx(mgr, txmsg);
1753 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1755 if (txmsg->reply.reply_type == 1) {
1762 drm_dp_put_mst_branch_device(mstb);
1763 drm_dp_put_port(port);
1767 int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr,
1768 struct drm_dp_mst_port *port, bool power_up)
1770 struct drm_dp_sideband_msg_tx *txmsg;
1773 port = drm_dp_get_validated_port_ref(mgr, port);
1777 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1779 drm_dp_put_port(port);
1783 txmsg->dst = port->parent;
1784 len = build_power_updown_phy(txmsg, port->port_num, power_up);
1785 drm_dp_queue_down_tx(mgr, txmsg);
1787 ret = drm_dp_mst_wait_tx_reply(port->parent, txmsg);
1789 if (txmsg->reply.reply_type == 1)
1795 drm_dp_put_port(port);
1799 EXPORT_SYMBOL(drm_dp_send_power_updown_phy);
1801 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1803 struct drm_dp_payload *payload)
1807 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1809 payload->payload_state = 0;
1812 payload->payload_state = DP_PAYLOAD_LOCAL;
1816 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1817 struct drm_dp_mst_port *port,
1819 struct drm_dp_payload *payload)
1822 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1825 payload->payload_state = DP_PAYLOAD_REMOTE;
1829 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1830 struct drm_dp_mst_port *port,
1832 struct drm_dp_payload *payload)
1834 DRM_DEBUG_KMS("\n");
1835 /* its okay for these to fail */
1837 drm_dp_payload_send_msg(mgr, port, id, 0);
1840 drm_dp_dpcd_write_payload(mgr, id, payload);
1841 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
1845 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1847 struct drm_dp_payload *payload)
1849 payload->payload_state = 0;
1854 * drm_dp_update_payload_part1() - Execute payload update part 1
1855 * @mgr: manager to use.
1857 * This iterates over all proposed virtual channels, and tries to
1858 * allocate space in the link for them. For 0->slots transitions,
1859 * this step just writes the VCPI to the MST device. For slots->0
1860 * transitions, this writes the updated VCPIs and removes the
1861 * remote VC payloads.
1863 * after calling this the driver should generate ACT and payload
1866 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1870 struct drm_dp_payload req_payload;
1871 struct drm_dp_mst_port *port;
1873 mutex_lock(&mgr->payload_lock);
1874 for (i = 0; i < mgr->max_payloads; i++) {
1875 /* solve the current payloads - compare to the hw ones
1876 - update the hw view */
1877 req_payload.start_slot = cur_slots;
1878 if (mgr->proposed_vcpis[i]) {
1879 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1880 port = drm_dp_get_validated_port_ref(mgr, port);
1882 mutex_unlock(&mgr->payload_lock);
1885 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1886 req_payload.vcpi = mgr->proposed_vcpis[i]->vcpi;
1889 req_payload.num_slots = 0;
1892 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1893 mgr->payloads[i].start_slot = req_payload.start_slot;
1895 /* work out what is required to happen with this payload */
1896 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
1898 /* need to push an update for this payload */
1899 if (req_payload.num_slots) {
1900 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
1901 mgr->payloads[i].num_slots = req_payload.num_slots;
1902 mgr->payloads[i].vcpi = req_payload.vcpi;
1903 } else if (mgr->payloads[i].num_slots) {
1904 mgr->payloads[i].num_slots = 0;
1905 drm_dp_destroy_payload_step1(mgr, port, mgr->payloads[i].vcpi, &mgr->payloads[i]);
1906 req_payload.payload_state = mgr->payloads[i].payload_state;
1907 mgr->payloads[i].start_slot = 0;
1909 mgr->payloads[i].payload_state = req_payload.payload_state;
1911 cur_slots += req_payload.num_slots;
1914 drm_dp_put_port(port);
1917 for (i = 0; i < mgr->max_payloads; i++) {
1918 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1919 DRM_DEBUG_KMS("removing payload %d\n", i);
1920 for (j = i; j < mgr->max_payloads - 1; j++) {
1921 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1922 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1923 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1924 set_bit(j + 1, &mgr->payload_mask);
1926 clear_bit(j + 1, &mgr->payload_mask);
1929 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1930 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1931 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1935 mutex_unlock(&mgr->payload_lock);
1939 EXPORT_SYMBOL(drm_dp_update_payload_part1);
1942 * drm_dp_update_payload_part2() - Execute payload update part 2
1943 * @mgr: manager to use.
1945 * This iterates over all proposed virtual channels, and tries to
1946 * allocate space in the link for them. For 0->slots transitions,
1947 * this step writes the remote VC payload commands. For slots->0
1948 * this just resets some internal state.
1950 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1952 struct drm_dp_mst_port *port;
1955 mutex_lock(&mgr->payload_lock);
1956 for (i = 0; i < mgr->max_payloads; i++) {
1958 if (!mgr->proposed_vcpis[i])
1961 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1963 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1964 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1965 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1966 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1967 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1970 mutex_unlock(&mgr->payload_lock);
1974 mutex_unlock(&mgr->payload_lock);
1977 EXPORT_SYMBOL(drm_dp_update_payload_part2);
1979 #if 0 /* unused as of yet */
1980 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1981 struct drm_dp_mst_port *port,
1982 int offset, int size)
1985 struct drm_dp_sideband_msg_tx *txmsg;
1987 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1991 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1992 txmsg->dst = port->parent;
1994 drm_dp_queue_down_tx(mgr, txmsg);
2000 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
2001 struct drm_dp_mst_port *port,
2002 int offset, int size, u8 *bytes)
2006 struct drm_dp_sideband_msg_tx *txmsg;
2007 struct drm_dp_mst_branch *mstb;
2009 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2013 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2019 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
2022 drm_dp_queue_down_tx(mgr, txmsg);
2024 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2026 if (txmsg->reply.reply_type == 1) {
2033 drm_dp_put_mst_branch_device(mstb);
2037 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
2039 struct drm_dp_sideband_msg_reply_body reply;
2041 reply.reply_type = 0;
2042 reply.req_type = req_type;
2043 drm_dp_encode_sideband_reply(&reply, msg);
2047 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
2048 struct drm_dp_mst_branch *mstb,
2049 int req_type, int seqno, bool broadcast)
2051 struct drm_dp_sideband_msg_tx *txmsg;
2053 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2058 txmsg->seqno = seqno;
2059 drm_dp_encode_up_ack_reply(txmsg, req_type);
2061 mutex_lock(&mgr->qlock);
2063 process_single_up_tx_qlock(mgr, txmsg);
2065 mutex_unlock(&mgr->qlock);
2071 static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
2075 switch (dp_link_bw) {
2077 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
2078 dp_link_bw, dp_link_count);
2081 case DP_LINK_BW_1_62:
2082 *out = 3 * dp_link_count;
2084 case DP_LINK_BW_2_7:
2085 *out = 5 * dp_link_count;
2087 case DP_LINK_BW_5_4:
2088 *out = 10 * dp_link_count;
2095 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
2096 * @mgr: manager to set state for
2097 * @mst_state: true to enable MST on this connector - false to disable.
2099 * This is called by the driver when it detects an MST capable device plugged
2100 * into a DP MST capable port, or when a DP MST capable device is unplugged.
2102 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
2105 struct drm_dp_mst_branch *mstb = NULL;
2107 mutex_lock(&mgr->lock);
2108 if (mst_state == mgr->mst_state)
2111 mgr->mst_state = mst_state;
2112 /* set the device into MST mode */
2114 WARN_ON(mgr->mst_primary);
2117 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
2118 if (ret != DP_RECEIVER_CAP_SIZE) {
2119 DRM_DEBUG_KMS("failed to read DPCD\n");
2123 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
2124 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
2130 /* add initial branch device at LCT 1 */
2131 mstb = drm_dp_add_mst_branch_device(1, NULL);
2138 /* give this the main reference */
2139 mgr->mst_primary = mstb;
2140 kref_get(&mgr->mst_primary->kref);
2142 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2143 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
2149 struct drm_dp_payload reset_pay;
2150 reset_pay.start_slot = 0;
2151 reset_pay.num_slots = 0x3f;
2152 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
2155 queue_work(system_long_wq, &mgr->work);
2159 /* disable MST on the device */
2160 mstb = mgr->mst_primary;
2161 mgr->mst_primary = NULL;
2162 /* this can fail if the device is gone */
2163 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
2165 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
2166 mgr->payload_mask = 0;
2167 set_bit(0, &mgr->payload_mask);
2172 mutex_unlock(&mgr->lock);
2174 drm_dp_put_mst_branch_device(mstb);
2178 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
2181 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
2182 * @mgr: manager to suspend
2184 * This function tells the MST device that we can't handle UP messages
2185 * anymore. This should stop it from sending any since we are suspended.
2187 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
2189 mutex_lock(&mgr->lock);
2190 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2191 DP_MST_EN | DP_UPSTREAM_IS_SRC);
2192 mutex_unlock(&mgr->lock);
2193 flush_work(&mgr->work);
2194 flush_work(&mgr->destroy_connector_work);
2196 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
2199 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
2200 * @mgr: manager to resume
2202 * This will fetch DPCD and see if the device is still there,
2203 * if it is, it will rewrite the MSTM control bits, and return.
2205 * if the device fails this returns -1, and the driver should do
2206 * a full MST reprobe, in case we were undocked.
2208 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
2212 mutex_lock(&mgr->lock);
2214 if (mgr->mst_primary) {
2218 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
2219 if (sret != DP_RECEIVER_CAP_SIZE) {
2220 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
2225 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2226 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
2228 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
2233 /* Some hubs forget their guids after they resume */
2234 sret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16);
2236 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
2240 drm_dp_check_mstb_guid(mgr->mst_primary, guid);
2247 mutex_unlock(&mgr->lock);
2250 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
2252 static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
2256 int replylen, origlen, curreply;
2258 struct drm_dp_sideband_msg_rx *msg;
2259 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
2260 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
2262 len = min(mgr->max_dpcd_transaction_bytes, 16);
2263 ret = drm_dp_dpcd_read(mgr->aux, basereg,
2266 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
2269 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
2271 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
2274 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
2279 while (replylen > 0) {
2280 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2281 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2284 DRM_DEBUG_KMS("failed to read a chunk (len %d, ret %d)\n",
2289 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2291 DRM_DEBUG_KMS("failed to build sideband msg\n");
2301 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2305 if (!drm_dp_get_one_sb_msg(mgr, false)) {
2306 memset(&mgr->down_rep_recv, 0,
2307 sizeof(struct drm_dp_sideband_msg_rx));
2311 if (mgr->down_rep_recv.have_eomt) {
2312 struct drm_dp_sideband_msg_tx *txmsg;
2313 struct drm_dp_mst_branch *mstb;
2315 mstb = drm_dp_get_mst_branch_device(mgr,
2316 mgr->down_rep_recv.initial_hdr.lct,
2317 mgr->down_rep_recv.initial_hdr.rad);
2320 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2321 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2325 /* find the message */
2326 slot = mgr->down_rep_recv.initial_hdr.seqno;
2327 mutex_lock(&mgr->qlock);
2328 txmsg = mstb->tx_slots[slot];
2329 /* remove from slots */
2330 mutex_unlock(&mgr->qlock);
2333 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2335 mgr->down_rep_recv.initial_hdr.seqno,
2336 mgr->down_rep_recv.initial_hdr.lct,
2337 mgr->down_rep_recv.initial_hdr.rad[0],
2338 mgr->down_rep_recv.msg[0]);
2339 drm_dp_put_mst_branch_device(mstb);
2340 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2344 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2345 if (txmsg->reply.reply_type == 1) {
2346 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);
2349 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2350 drm_dp_put_mst_branch_device(mstb);
2352 mutex_lock(&mgr->qlock);
2353 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2354 mstb->tx_slots[slot] = NULL;
2355 mutex_unlock(&mgr->qlock);
2357 wake_up_all(&mgr->tx_waitq);
2362 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2366 if (!drm_dp_get_one_sb_msg(mgr, true)) {
2367 memset(&mgr->up_req_recv, 0,
2368 sizeof(struct drm_dp_sideband_msg_rx));
2372 if (mgr->up_req_recv.have_eomt) {
2373 struct drm_dp_sideband_msg_req_body msg;
2374 struct drm_dp_mst_branch *mstb = NULL;
2377 if (!mgr->up_req_recv.initial_hdr.broadcast) {
2378 mstb = drm_dp_get_mst_branch_device(mgr,
2379 mgr->up_req_recv.initial_hdr.lct,
2380 mgr->up_req_recv.initial_hdr.rad);
2382 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2383 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2388 seqno = mgr->up_req_recv.initial_hdr.seqno;
2389 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2391 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2392 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
2395 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.conn_stat.guid);
2398 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2399 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2403 drm_dp_update_port(mstb, &msg.u.conn_stat);
2405 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);
2406 (*mgr->cbs->hotplug)(mgr);
2408 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2409 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false);
2411 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.resource_stat.guid);
2414 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2415 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2419 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2423 drm_dp_put_mst_branch_device(mstb);
2425 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2431 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2432 * @mgr: manager to notify irq for.
2433 * @esi: 4 bytes from SINK_COUNT_ESI
2434 * @handled: whether the hpd interrupt was consumed or not
2436 * This should be called from the driver when it detects a short IRQ,
2437 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2438 * topology manager will process the sideband messages received as a result
2441 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2448 if (sc != mgr->sink_count) {
2449 mgr->sink_count = sc;
2453 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2454 ret = drm_dp_mst_handle_down_rep(mgr);
2458 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2459 ret |= drm_dp_mst_handle_up_req(mgr);
2463 drm_dp_mst_kick_tx(mgr);
2466 EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2469 * drm_dp_mst_detect_port() - get connection status for an MST port
2470 * @connector: DRM connector for this port
2471 * @mgr: manager for this port
2472 * @port: unverified pointer to a port
2474 * This returns the current connection state for a port. It validates the
2475 * port pointer still exists so the caller doesn't require a reference
2477 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
2478 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2480 enum drm_connector_status status = connector_status_disconnected;
2482 /* we need to search for the port in the mgr in case its gone */
2483 port = drm_dp_get_validated_port_ref(mgr, port);
2485 return connector_status_disconnected;
2490 switch (port->pdt) {
2491 case DP_PEER_DEVICE_NONE:
2492 case DP_PEER_DEVICE_MST_BRANCHING:
2495 case DP_PEER_DEVICE_SST_SINK:
2496 status = connector_status_connected;
2497 /* for logical ports - cache the EDID */
2498 if (port->port_num >= 8 && !port->cached_edid) {
2499 port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
2502 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2504 status = connector_status_connected;
2508 drm_dp_put_port(port);
2511 EXPORT_SYMBOL(drm_dp_mst_detect_port);
2514 * drm_dp_mst_port_has_audio() - Check whether port has audio capability or not
2515 * @mgr: manager for this port
2516 * @port: unverified pointer to a port.
2518 * This returns whether the port supports audio or not.
2520 bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr,
2521 struct drm_dp_mst_port *port)
2525 port = drm_dp_get_validated_port_ref(mgr, port);
2528 ret = port->has_audio;
2529 drm_dp_put_port(port);
2532 EXPORT_SYMBOL(drm_dp_mst_port_has_audio);
2535 * drm_dp_mst_get_edid() - get EDID for an MST port
2536 * @connector: toplevel connector to get EDID for
2537 * @mgr: manager for this port
2538 * @port: unverified pointer to a port.
2540 * This returns an EDID for the port connected to a connector,
2541 * It validates the pointer still exists so the caller doesn't require a
2544 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2546 struct edid *edid = NULL;
2548 /* we need to search for the port in the mgr in case its gone */
2549 port = drm_dp_get_validated_port_ref(mgr, port);
2553 if (port->cached_edid)
2554 edid = drm_edid_duplicate(port->cached_edid);
2556 edid = drm_get_edid(connector, &port->aux.ddc);
2557 drm_mode_connector_set_tile_property(connector);
2559 port->has_audio = drm_detect_monitor_audio(edid);
2560 drm_dp_put_port(port);
2563 EXPORT_SYMBOL(drm_dp_mst_get_edid);
2566 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2567 * @mgr: manager to use
2568 * @pbn: payload bandwidth to convert into slots.
2570 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2575 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2577 /* max. time slots - one slot for MTP header */
2582 EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2584 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2585 struct drm_dp_vcpi *vcpi, int pbn, int slots)
2589 /* max. time slots - one slot for MTP header */
2594 vcpi->aligned_pbn = slots * mgr->pbn_div;
2595 vcpi->num_slots = slots;
2597 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2604 * drm_dp_atomic_find_vcpi_slots() - Find and add vcpi slots to the state
2605 * @state: global atomic state
2606 * @mgr: MST topology manager for the port
2607 * @port: port to find vcpi slots for
2608 * @pbn: bandwidth required for the mode in PBN
2611 * Total slots in the atomic state assigned for this port or error
2613 int drm_dp_atomic_find_vcpi_slots(struct drm_atomic_state *state,
2614 struct drm_dp_mst_topology_mgr *mgr,
2615 struct drm_dp_mst_port *port, int pbn)
2617 struct drm_dp_mst_topology_state *topology_state;
2620 topology_state = drm_atomic_get_mst_topology_state(state, mgr);
2621 if (IS_ERR(topology_state))
2622 return PTR_ERR(topology_state);
2624 port = drm_dp_get_validated_port_ref(mgr, port);
2627 req_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2628 DRM_DEBUG_KMS("vcpi slots req=%d, avail=%d\n",
2629 req_slots, topology_state->avail_slots);
2631 if (req_slots > topology_state->avail_slots) {
2632 drm_dp_put_port(port);
2636 topology_state->avail_slots -= req_slots;
2637 DRM_DEBUG_KMS("vcpi slots avail=%d", topology_state->avail_slots);
2639 drm_dp_put_port(port);
2642 EXPORT_SYMBOL(drm_dp_atomic_find_vcpi_slots);
2645 * drm_dp_atomic_release_vcpi_slots() - Release allocated vcpi slots
2646 * @state: global atomic state
2647 * @mgr: MST topology manager for the port
2648 * @slots: number of vcpi slots to release
2651 * 0 if @slots were added back to &drm_dp_mst_topology_state->avail_slots or
2652 * negative error code
2654 int drm_dp_atomic_release_vcpi_slots(struct drm_atomic_state *state,
2655 struct drm_dp_mst_topology_mgr *mgr,
2658 struct drm_dp_mst_topology_state *topology_state;
2660 topology_state = drm_atomic_get_mst_topology_state(state, mgr);
2661 if (IS_ERR(topology_state))
2662 return PTR_ERR(topology_state);
2664 /* We cannot rely on port->vcpi.num_slots to update
2665 * topology_state->avail_slots as the port may not exist if the parent
2666 * branch device was unplugged. This should be fixed by tracking
2667 * per-port slot allocation in drm_dp_mst_topology_state instead of
2668 * depending on the caller to tell us how many slots to release.
2670 topology_state->avail_slots += slots;
2671 DRM_DEBUG_KMS("vcpi slots released=%d, avail=%d\n",
2672 slots, topology_state->avail_slots);
2676 EXPORT_SYMBOL(drm_dp_atomic_release_vcpi_slots);
2679 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2680 * @mgr: manager for this port
2681 * @port: port to allocate a virtual channel for.
2682 * @pbn: payload bandwidth number to request
2683 * @slots: returned number of slots for this PBN.
2685 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2686 struct drm_dp_mst_port *port, int pbn, int slots)
2690 port = drm_dp_get_validated_port_ref(mgr, port);
2697 if (port->vcpi.vcpi > 0) {
2698 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2699 if (pbn == port->vcpi.pbn) {
2700 drm_dp_put_port(port);
2705 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn, slots);
2707 DRM_DEBUG_KMS("failed to init vcpi slots=%d max=63 ret=%d\n",
2708 DIV_ROUND_UP(pbn, mgr->pbn_div), ret);
2711 DRM_DEBUG_KMS("initing vcpi for pbn=%d slots=%d\n",
2712 pbn, port->vcpi.num_slots);
2714 drm_dp_put_port(port);
2719 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2721 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2724 port = drm_dp_get_validated_port_ref(mgr, port);
2728 slots = port->vcpi.num_slots;
2729 drm_dp_put_port(port);
2732 EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots);
2735 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2736 * @mgr: manager for this port
2737 * @port: unverified pointer to a port.
2739 * This just resets the number of slots for the ports VCPI for later programming.
2741 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2743 port = drm_dp_get_validated_port_ref(mgr, port);
2746 port->vcpi.num_slots = 0;
2747 drm_dp_put_port(port);
2749 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2752 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2753 * @mgr: manager for this port
2754 * @port: unverified port to deallocate vcpi for
2756 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2758 port = drm_dp_get_validated_port_ref(mgr, port);
2762 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2763 port->vcpi.num_slots = 0;
2765 port->vcpi.aligned_pbn = 0;
2766 port->vcpi.vcpi = 0;
2767 drm_dp_put_port(port);
2769 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2771 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2772 int id, struct drm_dp_payload *payload)
2774 u8 payload_alloc[3], status;
2778 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2779 DP_PAYLOAD_TABLE_UPDATED);
2781 payload_alloc[0] = id;
2782 payload_alloc[1] = payload->start_slot;
2783 payload_alloc[2] = payload->num_slots;
2785 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2787 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2792 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2794 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2798 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2801 usleep_range(10000, 20000);
2804 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2815 * drm_dp_check_act_status() - Check ACT handled status.
2816 * @mgr: manager to use
2818 * Check the payload status bits in the DPCD for ACT handled completion.
2820 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2827 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2830 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2834 if (status & DP_PAYLOAD_ACT_HANDLED)
2839 } while (count < 30);
2841 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2842 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2850 EXPORT_SYMBOL(drm_dp_check_act_status);
2853 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2854 * @clock: dot clock for the mode
2855 * @bpp: bpp for the mode.
2857 * This uses the formula in the spec to calculate the PBN value for a mode.
2859 int drm_dp_calc_pbn_mode(int clock, int bpp)
2869 * margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006
2870 * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on
2871 * common multiplier to render an integer PBN for all link rate/lane
2872 * counts combinations
2874 * peak_kbps *= (1006/1000)
2875 * peak_kbps *= (64/54)
2876 * peak_kbps *= 8 convert to bytes
2879 numerator = 64 * 1006;
2880 denominator = 54 * 8 * 1000 * 1000;
2883 peak_kbps = drm_fixp_from_fraction(kbps, denominator);
2885 return drm_fixp2int_ceil(peak_kbps);
2887 EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2889 static int test_calc_pbn_mode(void)
2892 ret = drm_dp_calc_pbn_mode(154000, 30);
2894 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
2895 154000, 30, 689, ret);
2898 ret = drm_dp_calc_pbn_mode(234000, 30);
2900 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
2901 234000, 30, 1047, ret);
2904 ret = drm_dp_calc_pbn_mode(297000, 24);
2906 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n",
2907 297000, 24, 1063, ret);
2913 /* we want to kick the TX after we've ack the up/down IRQs. */
2914 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2916 queue_work(system_long_wq, &mgr->tx_work);
2919 static void drm_dp_mst_dump_mstb(struct seq_file *m,
2920 struct drm_dp_mst_branch *mstb)
2922 struct drm_dp_mst_port *port;
2923 int tabs = mstb->lct;
2927 for (i = 0; i < tabs; i++)
2931 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2932 list_for_each_entry(port, &mstb->ports, next) {
2933 seq_printf(m, "%sport: %d: input: %d: pdt: %d, ddps: %d ldps: %d, sdp: %d/%d, %p, conn: %p\n", prefix, port->port_num, port->input, port->pdt, port->ddps, port->ldps, port->num_sdp_streams, port->num_sdp_stream_sinks, port, port->connector);
2935 drm_dp_mst_dump_mstb(m, port->mstb);
2939 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2944 for (i = 0; i < 64; i += 16) {
2945 if (drm_dp_dpcd_read(mgr->aux,
2946 DP_PAYLOAD_TABLE_UPDATE_STATUS + i,
2953 static void fetch_monitor_name(struct drm_dp_mst_topology_mgr *mgr,
2954 struct drm_dp_mst_port *port, char *name,
2957 struct edid *mst_edid;
2959 mst_edid = drm_dp_mst_get_edid(port->connector, mgr, port);
2960 drm_edid_get_monitor_name(mst_edid, name, namelen);
2964 * drm_dp_mst_dump_topology(): dump topology to seq file.
2965 * @m: seq_file to dump output to
2966 * @mgr: manager to dump current topology for.
2968 * helper to dump MST topology to a seq file for debugfs.
2970 void drm_dp_mst_dump_topology(struct seq_file *m,
2971 struct drm_dp_mst_topology_mgr *mgr)
2974 struct drm_dp_mst_port *port;
2976 mutex_lock(&mgr->lock);
2977 if (mgr->mst_primary)
2978 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2981 mutex_unlock(&mgr->lock);
2983 mutex_lock(&mgr->payload_lock);
2984 seq_printf(m, "vcpi: %lx %lx %d\n", mgr->payload_mask, mgr->vcpi_mask,
2987 for (i = 0; i < mgr->max_payloads; i++) {
2988 if (mgr->proposed_vcpis[i]) {
2991 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2992 fetch_monitor_name(mgr, port, name, sizeof(name));
2993 seq_printf(m, "vcpi %d: %d %d %d sink name: %s\n", i,
2994 port->port_num, port->vcpi.vcpi,
2995 port->vcpi.num_slots,
2996 (*name != 0) ? name : "Unknown");
2998 seq_printf(m, "vcpi %d:unused\n", i);
3000 for (i = 0; i < mgr->max_payloads; i++) {
3001 seq_printf(m, "payload %d: %d, %d, %d\n",
3003 mgr->payloads[i].payload_state,
3004 mgr->payloads[i].start_slot,
3005 mgr->payloads[i].num_slots);
3009 mutex_unlock(&mgr->payload_lock);
3011 mutex_lock(&mgr->lock);
3012 if (mgr->mst_primary) {
3016 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
3017 seq_printf(m, "dpcd: %*ph\n", DP_RECEIVER_CAP_SIZE, buf);
3018 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
3019 seq_printf(m, "faux/mst: %*ph\n", 2, buf);
3020 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
3021 seq_printf(m, "mst ctrl: %*ph\n", 1, buf);
3023 /* dump the standard OUI branch header */
3024 ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE);
3025 seq_printf(m, "branch oui: %*phN devid: ", 3, buf);
3026 for (i = 0x3; i < 0x8 && buf[i]; i++)
3027 seq_printf(m, "%c", buf[i]);
3028 seq_printf(m, " revision: hw: %x.%x sw: %x.%x\n",
3029 buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]);
3030 if (dump_dp_payload_table(mgr, buf))
3031 seq_printf(m, "payload table: %*ph\n", 63, buf);
3035 mutex_unlock(&mgr->lock);
3038 EXPORT_SYMBOL(drm_dp_mst_dump_topology);
3040 static void drm_dp_tx_work(struct work_struct *work)
3042 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
3044 mutex_lock(&mgr->qlock);
3045 if (!list_empty(&mgr->tx_msg_downq))
3046 process_single_down_tx_qlock(mgr);
3047 mutex_unlock(&mgr->qlock);
3050 static void drm_dp_free_mst_port(struct kref *kref)
3052 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
3053 kref_put(&port->parent->kref, drm_dp_free_mst_branch_device);
3057 static void drm_dp_destroy_connector_work(struct work_struct *work)
3059 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
3060 struct drm_dp_mst_port *port;
3061 bool send_hotplug = false;
3063 * Not a regular list traverse as we have to drop the destroy
3064 * connector lock before destroying the connector, to avoid AB->BA
3065 * ordering between this lock and the config mutex.
3068 mutex_lock(&mgr->destroy_connector_lock);
3069 port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next);
3071 mutex_unlock(&mgr->destroy_connector_lock);
3074 list_del(&port->next);
3075 mutex_unlock(&mgr->destroy_connector_lock);
3077 kref_init(&port->kref);
3078 INIT_LIST_HEAD(&port->next);
3080 mgr->cbs->destroy_connector(mgr, port->connector);
3082 drm_dp_port_teardown_pdt(port, port->pdt);
3083 port->pdt = DP_PEER_DEVICE_NONE;
3085 if (!port->input && port->vcpi.vcpi > 0) {
3086 drm_dp_mst_reset_vcpi_slots(mgr, port);
3087 drm_dp_update_payload_part1(mgr);
3088 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
3091 kref_put(&port->kref, drm_dp_free_mst_port);
3092 send_hotplug = true;
3095 (*mgr->cbs->hotplug)(mgr);
3098 static struct drm_private_state *
3099 drm_dp_mst_duplicate_state(struct drm_private_obj *obj)
3101 struct drm_dp_mst_topology_state *state;
3103 state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
3107 __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
3109 return &state->base;
3112 static void drm_dp_mst_destroy_state(struct drm_private_obj *obj,
3113 struct drm_private_state *state)
3115 struct drm_dp_mst_topology_state *mst_state =
3116 to_dp_mst_topology_state(state);
3121 static const struct drm_private_state_funcs mst_state_funcs = {
3122 .atomic_duplicate_state = drm_dp_mst_duplicate_state,
3123 .atomic_destroy_state = drm_dp_mst_destroy_state,
3127 * drm_atomic_get_mst_topology_state: get MST topology state
3129 * @state: global atomic state
3130 * @mgr: MST topology manager, also the private object in this case
3132 * This function wraps drm_atomic_get_priv_obj_state() passing in the MST atomic
3133 * state vtable so that the private object state returned is that of a MST
3134 * topology object. Also, drm_atomic_get_private_obj_state() expects the caller
3135 * to care of the locking, so warn if don't hold the connection_mutex.
3139 * The MST topology state or error pointer.
3141 struct drm_dp_mst_topology_state *drm_atomic_get_mst_topology_state(struct drm_atomic_state *state,
3142 struct drm_dp_mst_topology_mgr *mgr)
3144 struct drm_device *dev = mgr->dev;
3146 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
3147 return to_dp_mst_topology_state(drm_atomic_get_private_obj_state(state, &mgr->base));
3149 EXPORT_SYMBOL(drm_atomic_get_mst_topology_state);
3152 * drm_dp_mst_topology_mgr_init - initialise a topology manager
3153 * @mgr: manager struct to initialise
3154 * @dev: device providing this structure - for i2c addition.
3155 * @aux: DP helper aux channel to talk to this device
3156 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
3157 * @max_payloads: maximum number of payloads this GPU can source
3158 * @conn_base_id: the connector object ID the MST device is connected to.
3160 * Return 0 for success, or negative error code on failure
3162 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
3163 struct drm_device *dev, struct drm_dp_aux *aux,
3164 int max_dpcd_transaction_bytes,
3165 int max_payloads, int conn_base_id)
3167 struct drm_dp_mst_topology_state *mst_state;
3169 mutex_init(&mgr->lock);
3170 mutex_init(&mgr->qlock);
3171 mutex_init(&mgr->payload_lock);
3172 mutex_init(&mgr->destroy_connector_lock);
3173 INIT_LIST_HEAD(&mgr->tx_msg_downq);
3174 INIT_LIST_HEAD(&mgr->destroy_connector_list);
3175 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
3176 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
3177 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work);
3178 init_waitqueue_head(&mgr->tx_waitq);
3181 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
3182 mgr->max_payloads = max_payloads;
3183 mgr->conn_base_id = conn_base_id;
3184 if (max_payloads + 1 > sizeof(mgr->payload_mask) * 8 ||
3185 max_payloads + 1 > sizeof(mgr->vcpi_mask) * 8)
3187 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
3190 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
3191 if (!mgr->proposed_vcpis)
3193 set_bit(0, &mgr->payload_mask);
3194 if (test_calc_pbn_mode() < 0)
3195 DRM_ERROR("MST PBN self-test failed\n");
3197 mst_state = kzalloc(sizeof(*mst_state), GFP_KERNEL);
3198 if (mst_state == NULL)
3201 mst_state->mgr = mgr;
3203 /* max. time slots - one slot for MTP header */
3204 mst_state->avail_slots = 63;
3206 drm_atomic_private_obj_init(&mgr->base,
3212 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
3215 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
3216 * @mgr: manager to destroy
3218 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
3220 flush_work(&mgr->work);
3221 flush_work(&mgr->destroy_connector_work);
3222 mutex_lock(&mgr->payload_lock);
3223 kfree(mgr->payloads);
3224 mgr->payloads = NULL;
3225 kfree(mgr->proposed_vcpis);
3226 mgr->proposed_vcpis = NULL;
3227 mutex_unlock(&mgr->payload_lock);
3230 drm_atomic_private_obj_fini(&mgr->base);
3233 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
3236 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
3239 struct drm_dp_aux *aux = adapter->algo_data;
3240 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
3241 struct drm_dp_mst_branch *mstb;
3242 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
3244 bool reading = false;
3245 struct drm_dp_sideband_msg_req_body msg;
3246 struct drm_dp_sideband_msg_tx *txmsg = NULL;
3249 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
3253 /* construct i2c msg */
3254 /* see if last msg is a read */
3255 if (msgs[num - 1].flags & I2C_M_RD)
3258 if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) {
3259 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
3264 memset(&msg, 0, sizeof(msg));
3265 msg.req_type = DP_REMOTE_I2C_READ;
3266 msg.u.i2c_read.num_transactions = num - 1;
3267 msg.u.i2c_read.port_number = port->port_num;
3268 for (i = 0; i < num - 1; i++) {
3269 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
3270 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
3271 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
3273 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
3274 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
3276 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
3283 drm_dp_encode_sideband_req(&msg, txmsg);
3285 drm_dp_queue_down_tx(mgr, txmsg);
3287 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
3290 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
3294 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
3298 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
3303 drm_dp_put_mst_branch_device(mstb);
3307 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
3309 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
3310 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
3311 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
3312 I2C_FUNC_10BIT_ADDR;
3315 static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
3316 .functionality = drm_dp_mst_i2c_functionality,
3317 .master_xfer = drm_dp_mst_i2c_xfer,
3321 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
3322 * @aux: DisplayPort AUX channel
3324 * Returns 0 on success or a negative error code on failure.
3326 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
3328 aux->ddc.algo = &drm_dp_mst_i2c_algo;
3329 aux->ddc.algo_data = aux;
3330 aux->ddc.retries = 3;
3332 aux->ddc.class = I2C_CLASS_DDC;
3333 aux->ddc.owner = THIS_MODULE;
3334 aux->ddc.dev.parent = aux->dev;
3335 aux->ddc.dev.of_node = aux->dev->of_node;
3337 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
3338 sizeof(aux->ddc.name));
3340 return i2c_add_adapter(&aux->ddc);
3344 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
3345 * @aux: DisplayPort AUX channel
3347 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
3349 i2c_del_adapter(&aux->ddc);