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[mirror_ubuntu-artful-kernel.git] / drivers / gpu / drm / drm_dp_mst_topology.c
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ad7f8a1f
DA		 1/*
2 * Copyright © 2014 Red Hat
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#include <linux/kernel.h>
24#include <linux/delay.h>
25#include <linux/init.h>
26#include <linux/errno.h>
27#include <linux/sched.h>
75bc08ab 28#include <linux/seq_file.h>
ad7f8a1f
DA		 29#include <linux/i2c.h>
30#include <drm/drm_dp_mst_helper.h>
31#include <drm/drmP.h>
32
33#include <drm/drm_fixed.h>
34
35/**
36 * DOC: dp mst helper
37 *
38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
39 * protocol. The helpers contain a topology manager and bandwidth manager.
40 * The helpers encapsulate the sending and received of sideband msgs.
41 */
42static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
43 char *buf);
44static int test_calc_pbn_mode(void);
45
46static void drm_dp_put_port(struct drm_dp_mst_port *port);
47
48static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
49 int id,
50 struct drm_dp_payload *payload);
51
52static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
53 struct drm_dp_mst_port *port,
54 int offset, int size, u8 *bytes);
55
56static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
57 struct drm_dp_mst_branch *mstb);
58static 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);
61static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
62 u8 *guid);
63
64static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
65static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
66static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
67/* sideband msg handling */
68static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
69{
70 u8 bitmask = 0x80;
71 u8 bitshift = 7;
72 u8 array_index = 0;
73 int number_of_bits = num_nibbles * 4;
74 u8 remainder = 0;
75
76 while (number_of_bits != 0) {
77 number_of_bits--;
78 remainder <<= 1;
79 remainder |= (data[array_index] & bitmask) >> bitshift;
80 bitmask >>= 1;
81 bitshift--;
82 if (bitmask == 0) {
83 bitmask = 0x80;
84 bitshift = 7;
85 array_index++;
86 }
87 if ((remainder & 0x10) == 0x10)
88 remainder ^= 0x13;
89 }
90
91 number_of_bits = 4;
92 while (number_of_bits != 0) {
93 number_of_bits--;
94 remainder <<= 1;
95 if ((remainder & 0x10) != 0)
96 remainder ^= 0x13;
97 }
98
99 return remainder;
100}
101
102static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
103{
104 u8 bitmask = 0x80;
105 u8 bitshift = 7;
106 u8 array_index = 0;
107 int number_of_bits = number_of_bytes * 8;
108 u16 remainder = 0;
109
110 while (number_of_bits != 0) {
111 number_of_bits--;
112 remainder <<= 1;
113 remainder |= (data[array_index] & bitmask) >> bitshift;
114 bitmask >>= 1;
115 bitshift--;
116 if (bitmask == 0) {
117 bitmask = 0x80;
118 bitshift = 7;
119 array_index++;
120 }
121 if ((remainder & 0x100) == 0x100)
122 remainder ^= 0xd5;
123 }
124
125 number_of_bits = 8;
126 while (number_of_bits != 0) {
127 number_of_bits--;
128 remainder <<= 1;
129 if ((remainder & 0x100) != 0)
130 remainder ^= 0xd5;
131 }
132
133 return remainder & 0xff;
134}
135static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
136{
137 u8 size = 3;
138 size += (hdr->lct / 2);
139 return size;
140}
141
142static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
143 u8 *buf, int *len)
144{
145 int idx = 0;
146 int i;
147 u8 crc4;
148 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
149 for (i = 0; i < (hdr->lct / 2); i++)
150 buf[idx++] = hdr->rad[i];
151 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
152 (hdr->msg_len & 0x3f);
153 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
154
155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
156 buf[idx - 1] |= (crc4 & 0xf);
157
158 *len = idx;
159}
160
161static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
162 u8 *buf, int buflen, u8 *hdrlen)
163{
164 u8 crc4;
165 u8 len;
166 int i;
167 u8 idx;
168 if (buf[0] == 0)
169 return false;
170 len = 3;
171 len += ((buf[0] & 0xf0) >> 4) / 2;
172 if (len > buflen)
173 return false;
174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
175
176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
178 return false;
179 }
180
181 hdr->lct = (buf[0] & 0xf0) >> 4;
182 hdr->lcr = (buf[0] & 0xf);
183 idx = 1;
184 for (i = 0; i < (hdr->lct / 2); i++)
185 hdr->rad[i] = buf[idx++];
186 hdr->broadcast = (buf[idx] >> 7) & 0x1;
187 hdr->path_msg = (buf[idx] >> 6) & 0x1;
188 hdr->msg_len = buf[idx] & 0x3f;
189 idx++;
190 hdr->somt = (buf[idx] >> 7) & 0x1;
191 hdr->eomt = (buf[idx] >> 6) & 0x1;
192 hdr->seqno = (buf[idx] >> 4) & 0x1;
193 idx++;
194 *hdrlen = idx;
195 return true;
196}
197
198static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
199 struct drm_dp_sideband_msg_tx *raw)
200{
201 int idx = 0;
202 int i;
203 u8 *buf = raw->msg;
204 buf[idx++] = req->req_type & 0x7f;
205
206 switch (req->req_type) {
207 case DP_ENUM_PATH_RESOURCES:
208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
209 idx++;
210 break;
211 case DP_ALLOCATE_PAYLOAD:
212 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
213 (req->u.allocate_payload.number_sdp_streams & 0xf);
214 idx++;
215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
216 idx++;
217 buf[idx] = (req->u.allocate_payload.pbn >> 8);
218 idx++;
219 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
220 idx++;
221 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
222 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
223 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
224 idx++;
225 }
226 if (req->u.allocate_payload.number_sdp_streams & 1) {
227 i = req->u.allocate_payload.number_sdp_streams - 1;
228 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
229 idx++;
230 }
231 break;
232 case DP_QUERY_PAYLOAD:
233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
234 idx++;
235 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
236 idx++;
237 break;
238 case DP_REMOTE_DPCD_READ:
239 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
240 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
241 idx++;
242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
243 idx++;
244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
245 idx++;
246 buf[idx] = (req->u.dpcd_read.num_bytes);
247 idx++;
248 break;
249
250 case DP_REMOTE_DPCD_WRITE:
251 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
252 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
253 idx++;
254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
255 idx++;
256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
257 idx++;
258 buf[idx] = (req->u.dpcd_write.num_bytes);
259 idx++;
260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
261 idx += req->u.dpcd_write.num_bytes;
262 break;
263 case DP_REMOTE_I2C_READ:
264 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
265 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
266 idx++;
267 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
268 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
269 idx++;
270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
271 idx++;
272 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
273 idx += req->u.i2c_read.transactions[i].num_bytes;
274
275 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
276 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
277 idx++;
278 }
279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
280 idx++;
281 buf[idx] = (req->u.i2c_read.num_bytes_read);
282 idx++;
283 break;
284
285 case DP_REMOTE_I2C_WRITE:
286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
287 idx++;
288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
289 idx++;
290 buf[idx] = (req->u.i2c_write.num_bytes);
291 idx++;
292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
293 idx += req->u.i2c_write.num_bytes;
294 break;
295 }
296 raw->cur_len = idx;
297}
298
299static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
300{
301 u8 crc4;
302 crc4 = drm_dp_msg_data_crc4(msg, len);
303 msg[len] = crc4;
304}
305
306static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
307 struct drm_dp_sideband_msg_tx *raw)
308{
309 int idx = 0;
310 u8 *buf = raw->msg;
311
312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
313
314 raw->cur_len = idx;
315}
316
317/* this adds a chunk of msg to the builder to get the final msg */
318static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
319 u8 *replybuf, u8 replybuflen, bool hdr)
320{
321 int ret;
322 u8 crc4;
323
324 if (hdr) {
325 u8 hdrlen;
326 struct drm_dp_sideband_msg_hdr recv_hdr;
327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
328 if (ret == false) {
329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
330 return false;
331 }
332
333 /* get length contained in this portion */
334 msg->curchunk_len = recv_hdr.msg_len;
335 msg->curchunk_hdrlen = hdrlen;
336
337 /* we have already gotten an somt - don't bother parsing */
338 if (recv_hdr.somt && msg->have_somt)
339 return false;
340
341 if (recv_hdr.somt) {
342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
343 msg->have_somt = true;
344 }
345 if (recv_hdr.eomt)
346 msg->have_eomt = true;
347
348 /* copy the bytes for the remainder of this header chunk */
349 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
350 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
351 } else {
352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
353 msg->curchunk_idx += replybuflen;
354 }
355
356 if (msg->curchunk_idx >= msg->curchunk_len) {
357 /* do CRC */
358 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
359 /* copy chunk into bigger msg */
360 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
361 msg->curlen += msg->curchunk_len - 1;
362 }
363 return true;
364}
365
366static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
367 struct drm_dp_sideband_msg_reply_body *repmsg)
368{
369 int idx = 1;
370 int i;
371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
372 idx += 16;
373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
374 idx++;
375 if (idx > raw->curlen)
376 goto fail_len;
377 for (i = 0; i < repmsg->u.link_addr.nports; i++) {
378 if (raw->msg[idx] & 0x80)
379 repmsg->u.link_addr.ports[i].input_port = 1;
380
381 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
382 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
383
384 idx++;
385 if (idx > raw->curlen)
386 goto fail_len;
387 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
388 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
389 if (repmsg->u.link_addr.ports[i].input_port == 0)
390 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
391 idx++;
392 if (idx > raw->curlen)
393 goto fail_len;
394 if (repmsg->u.link_addr.ports[i].input_port == 0) {
395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
396 idx++;
397 if (idx > raw->curlen)
398 goto fail_len;
399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
400 idx += 16;
401 if (idx > raw->curlen)
402 goto fail_len;
403 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
404 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
405 idx++;
406
407 }
408 if (idx > raw->curlen)
409 goto fail_len;
410 }
411
412 return true;
413fail_len:
414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
415 return false;
416}
417
418static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
419 struct drm_dp_sideband_msg_reply_body *repmsg)
420{
421 int idx = 1;
422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
423 idx++;
424 if (idx > raw->curlen)
425 goto fail_len;
426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
427 if (idx > raw->curlen)
428 goto fail_len;
429
430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
431 return true;
432fail_len:
433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
434 return false;
435}
436
437static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
438 struct drm_dp_sideband_msg_reply_body *repmsg)
439{
440 int idx = 1;
441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
442 idx++;
443 if (idx > raw->curlen)
444 goto fail_len;
445 return true;
446fail_len:
447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
448 return false;
449}
450
451static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
452 struct drm_dp_sideband_msg_reply_body *repmsg)
453{
454 int idx = 1;
455
456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
457 idx++;
458 if (idx > raw->curlen)
459 goto fail_len;
460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
461 idx++;
462 /* TODO check */
463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
464 return true;
465fail_len:
466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
467 return false;
468}
469
470static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
471 struct drm_dp_sideband_msg_reply_body *repmsg)
472{
473 int idx = 1;
474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
475 idx++;
476 if (idx > raw->curlen)
477 goto fail_len;
478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
479 idx += 2;
480 if (idx > raw->curlen)
481 goto fail_len;
482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
483 idx += 2;
484 if (idx > raw->curlen)
485 goto fail_len;
486 return true;
487fail_len:
488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
489 return false;
490}
491
492static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
493 struct drm_dp_sideband_msg_reply_body *repmsg)
494{
495 int idx = 1;
496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
497 idx++;
498 if (idx > raw->curlen)
499 goto fail_len;
500 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
501 idx++;
502 if (idx > raw->curlen)
503 goto fail_len;
504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
505 idx += 2;
506 if (idx > raw->curlen)
507 goto fail_len;
508 return true;
509fail_len:
510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
511 return false;
512}
513
514static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
515 struct drm_dp_sideband_msg_reply_body *repmsg)
516{
517 int idx = 1;
518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
519 idx++;
520 if (idx > raw->curlen)
521 goto fail_len;
522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
523 idx += 2;
524 if (idx > raw->curlen)
525 goto fail_len;
526 return true;
527fail_len:
528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
529 return false;
530}
531
532static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
533 struct drm_dp_sideband_msg_reply_body *msg)
534{
535 memset(msg, 0, sizeof(*msg));
536 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
537 msg->req_type = (raw->msg[0] & 0x7f);
538
539 if (msg->reply_type) {
540 memcpy(msg->u.nak.guid, &raw->msg[1], 16);
541 msg->u.nak.reason = raw->msg[17];
542 msg->u.nak.nak_data = raw->msg[18];
543 return false;
544 }
545
546 switch (msg->req_type) {
547 case DP_LINK_ADDRESS:
548 return drm_dp_sideband_parse_link_address(raw, msg);
549 case DP_QUERY_PAYLOAD:
550 return drm_dp_sideband_parse_query_payload_ack(raw, msg);
551 case DP_REMOTE_DPCD_READ:
552 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
553 case DP_REMOTE_DPCD_WRITE:
554 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
555 case DP_REMOTE_I2C_READ:
556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
557 case DP_ENUM_PATH_RESOURCES:
558 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
559 case DP_ALLOCATE_PAYLOAD:
560 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
561 default:
562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
563 return false;
564 }
565}
566
567static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
568 struct drm_dp_sideband_msg_req_body *msg)
569{
570 int idx = 1;
571
572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
573 idx++;
574 if (idx > raw->curlen)
575 goto fail_len;
576
577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
578 idx += 16;
579 if (idx > raw->curlen)
580 goto fail_len;
581
582 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
583 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
584 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
585 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
586 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
587 idx++;
588 return true;
589fail_len:
590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
591 return false;
592}
593
594static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
595 struct drm_dp_sideband_msg_req_body *msg)
596{
597 int idx = 1;
598
599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
600 idx++;
601 if (idx > raw->curlen)
602 goto fail_len;
603
604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
605 idx += 16;
606 if (idx > raw->curlen)
607 goto fail_len;
608
609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
610 idx++;
611 return true;
612fail_len:
613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
614 return false;
615}
616
617static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
618 struct drm_dp_sideband_msg_req_body *msg)
619{
620 memset(msg, 0, sizeof(*msg));
621 msg->req_type = (raw->msg[0] & 0x7f);
622
623 switch (msg->req_type) {
624 case DP_CONNECTION_STATUS_NOTIFY:
625 return drm_dp_sideband_parse_connection_status_notify(raw, msg);
626 case DP_RESOURCE_STATUS_NOTIFY:
627 return drm_dp_sideband_parse_resource_status_notify(raw, msg);
628 default:
629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
630 return false;
631 }
632}
633
634static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
635{
636 struct drm_dp_sideband_msg_req_body req;
637
638 req.req_type = DP_REMOTE_DPCD_WRITE;
639 req.u.dpcd_write.port_number = port_num;
640 req.u.dpcd_write.dpcd_address = offset;
641 req.u.dpcd_write.num_bytes = num_bytes;
642 req.u.dpcd_write.bytes = bytes;
643 drm_dp_encode_sideband_req(&req, msg);
644
645 return 0;
646}
647
648static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
649{
650 struct drm_dp_sideband_msg_req_body req;
651
652 req.req_type = DP_LINK_ADDRESS;
653 drm_dp_encode_sideband_req(&req, msg);
654 return 0;
655}
656
657static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
658{
659 struct drm_dp_sideband_msg_req_body req;
660
661 req.req_type = DP_ENUM_PATH_RESOURCES;
662 req.u.port_num.port_number = port_num;
663 drm_dp_encode_sideband_req(&req, msg);
664 msg->path_msg = true;
665 return 0;
666}
667
668static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
669 u8 vcpi, uint16_t pbn)
670{
671 struct drm_dp_sideband_msg_req_body req;
672 memset(&req, 0, sizeof(req));
673 req.req_type = DP_ALLOCATE_PAYLOAD;
674 req.u.allocate_payload.port_number = port_num;
675 req.u.allocate_payload.vcpi = vcpi;
676 req.u.allocate_payload.pbn = pbn;
677 drm_dp_encode_sideband_req(&req, msg);
678 msg->path_msg = true;
679 return 0;
680}
681
682static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
683 struct drm_dp_vcpi *vcpi)
684{
685 int ret;
686
687 mutex_lock(&mgr->payload_lock);
688 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1);
689 if (ret > mgr->max_payloads) {
690 ret = -EINVAL;
691 DRM_DEBUG_KMS("out of payload ids %d\n", ret);
692 goto out_unlock;
693 }
694
695 set_bit(ret, &mgr->payload_mask);
696 vcpi->vcpi = ret;
697 mgr->proposed_vcpis[ret - 1] = vcpi;
698out_unlock:
699 mutex_unlock(&mgr->payload_lock);
700 return ret;
701}
702
703static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
704 int id)
705{
706 if (id == 0)
707 return;
708
709 mutex_lock(&mgr->payload_lock);
710 DRM_DEBUG_KMS("putting payload %d\n", id);
711 clear_bit(id, &mgr->payload_mask);
712 mgr->proposed_vcpis[id - 1] = NULL;
713 mutex_unlock(&mgr->payload_lock);
714}
715
716static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
717 struct drm_dp_sideband_msg_tx *txmsg)
718{
719 bool ret;
720 mutex_lock(&mgr->qlock);
721 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
722 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
723 mutex_unlock(&mgr->qlock);
724 return ret;
725}
726
727static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
728 struct drm_dp_sideband_msg_tx *txmsg)
729{
730 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
731 int ret;
732
733 ret = wait_event_timeout(mgr->tx_waitq,
734 check_txmsg_state(mgr, txmsg),
735 (4 * HZ));
736 mutex_lock(&mstb->mgr->qlock);
737 if (ret > 0) {
738 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
739 ret = -EIO;
740 goto out;
741 }
742 } else {
743 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
744
745 /* dump some state */
746 ret = -EIO;
747
748 /* remove from q */
749 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
750 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
751 list_del(&txmsg->next);
752 }
753
754 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
755 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
756 mstb->tx_slots[txmsg->seqno] = NULL;
757 }
758 }
759out:
760 mutex_unlock(&mgr->qlock);
761
762 return ret;
763}
764
765static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
766{
767 struct drm_dp_mst_branch *mstb;
768
769 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
770 if (!mstb)
771 return NULL;
772
773 mstb->lct = lct;
774 if (lct > 1)
775 memcpy(mstb->rad, rad, lct / 2);
776 INIT_LIST_HEAD(&mstb->ports);
777 kref_init(&mstb->kref);
778 return mstb;
779}
780
781static void drm_dp_destroy_mst_branch_device(struct kref *kref)
782{
783 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
784 struct drm_dp_mst_port *port, *tmp;
785 bool wake_tx = false;
786
787 cancel_work_sync(&mstb->mgr->work);
788
789 /*
790 * destroy all ports - don't need lock
791 * as there are no more references to the mst branch
792 * device at this point.
793 */
794 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
795 list_del(&port->next);
796 drm_dp_put_port(port);
797 }
798
799 /* drop any tx slots msg */
800 mutex_lock(&mstb->mgr->qlock);
801 if (mstb->tx_slots[0]) {
802 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
803 mstb->tx_slots[0] = NULL;
804 wake_tx = true;
805 }
806 if (mstb->tx_slots[1]) {
807 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
808 mstb->tx_slots[1] = NULL;
809 wake_tx = true;
810 }
811 mutex_unlock(&mstb->mgr->qlock);
812
813 if (wake_tx)
814 wake_up(&mstb->mgr->tx_waitq);
815 kfree(mstb);
816}
817
818static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
819{
820 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
821}
822
823
824static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
825{
826 switch (old_pdt) {
827 case DP_PEER_DEVICE_DP_LEGACY_CONV:
828 case DP_PEER_DEVICE_SST_SINK:
829 /* remove i2c over sideband */
830 drm_dp_mst_unregister_i2c_bus(&port->aux);
831 break;
832 case DP_PEER_DEVICE_MST_BRANCHING:
833 drm_dp_put_mst_branch_device(port->mstb);
834 port->mstb = NULL;
835 break;
836 }
837}
838
839static void drm_dp_destroy_port(struct kref *kref)
840{
841 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
842 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
843 if (!port->input) {
844 port->vcpi.num_slots = 0;
845 if (port->connector)
846 (*port->mgr->cbs->destroy_connector)(mgr, port->connector);
847 drm_dp_port_teardown_pdt(port, port->pdt);
848
849 if (!port->input && port->vcpi.vcpi > 0)
850 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
851 }
852 kfree(port);
853
854 (*mgr->cbs->hotplug)(mgr);
855}
856
857static void drm_dp_put_port(struct drm_dp_mst_port *port)
858{
859 kref_put(&port->kref, drm_dp_destroy_port);
860}
861
862static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find)
863{
864 struct drm_dp_mst_port *port;
865 struct drm_dp_mst_branch *rmstb;
866 if (to_find == mstb) {
867 kref_get(&mstb->kref);
868 return mstb;
869 }
870 list_for_each_entry(port, &mstb->ports, next) {
871 if (port->mstb) {
872 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
873 if (rmstb)
874 return rmstb;
875 }
876 }
877 return NULL;
878}
879
880static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb)
881{
882 struct drm_dp_mst_branch *rmstb = NULL;
883 mutex_lock(&mgr->lock);
884 if (mgr->mst_primary)
885 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
886 mutex_unlock(&mgr->lock);
887 return rmstb;
888}
889
890static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find)
891{
892 struct drm_dp_mst_port *port, *mport;
893
894 list_for_each_entry(port, &mstb->ports, next) {
895 if (port == to_find) {
896 kref_get(&port->kref);
897 return port;
898 }
899 if (port->mstb) {
900 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
901 if (mport)
902 return mport;
903 }
904 }
905 return NULL;
906}
907
908static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
909{
910 struct drm_dp_mst_port *rport = NULL;
911 mutex_lock(&mgr->lock);
912 if (mgr->mst_primary)
913 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
914 mutex_unlock(&mgr->lock);
915 return rport;
916}
917
918static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
919{
920 struct drm_dp_mst_port *port;
921
922 list_for_each_entry(port, &mstb->ports, next) {
923 if (port->port_num == port_num) {
924 kref_get(&port->kref);
925 return port;
926 }
927 }
928
929 return NULL;
930}
931
932/*
933 * calculate a new RAD for this MST branch device
934 * if parent has an LCT of 2 then it has 1 nibble of RAD,
935 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
936 */
937static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
938 u8 *rad)
939{
940 int lct = port->parent->lct;
941 int shift = 4;
942 int idx = lct / 2;
943 if (lct > 1) {
944 memcpy(rad, port->parent->rad, idx);
945 shift = (lct % 2) ? 4 : 0;
946 } else
947 rad[0] = 0;
948
949 rad[idx] |= port->port_num << shift;
950 return lct + 1;
951}
952
953/*
954 * return sends link address for new mstb
955 */
956static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
957{
958 int ret;
959 u8 rad[6], lct;
960 bool send_link = false;
961 switch (port->pdt) {
962 case DP_PEER_DEVICE_DP_LEGACY_CONV:
963 case DP_PEER_DEVICE_SST_SINK:
964 /* add i2c over sideband */
965 ret = drm_dp_mst_register_i2c_bus(&port->aux);
966 break;
967 case DP_PEER_DEVICE_MST_BRANCHING:
968 lct = drm_dp_calculate_rad(port, rad);
969
970 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
971 port->mstb->mgr = port->mgr;
972 port->mstb->port_parent = port;
973
974 send_link = true;
975 break;
976 }
977 return send_link;
978}
979
980static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
981 struct drm_dp_mst_port *port)
982{
983 int ret;
984 if (port->dpcd_rev >= 0x12) {
985 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
986 if (!port->guid_valid) {
987 ret = drm_dp_send_dpcd_write(mstb->mgr,
988 port,
989 DP_GUID,
990 16, port->guid);
991 port->guid_valid = true;
992 }
993 }
994}
995
996static void build_mst_prop_path(struct drm_dp_mst_port *port,
997 struct drm_dp_mst_branch *mstb,
998 char *proppath)
999{
1000 int i;
1001 char temp[8];
1002 snprintf(proppath, 255, "mst:%d", mstb->mgr->conn_base_id);
1003 for (i = 0; i < (mstb->lct - 1); i++) {
1004 int shift = (i % 2) ? 0 : 4;
1005 int port_num = mstb->rad[i / 2] >> shift;
1006 snprintf(temp, 8, "-%d", port_num);
1007 strncat(proppath, temp, 255);
1008 }
1009 snprintf(temp, 8, "-%d", port->port_num);
1010 strncat(proppath, temp, 255);
1011}
1012
1013static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1014 struct device *dev,
1015 struct drm_dp_link_addr_reply_port *port_msg)
1016{
1017 struct drm_dp_mst_port *port;
1018 bool ret;
1019 bool created = false;
1020 int old_pdt = 0;
1021 int old_ddps = 0;
1022 port = drm_dp_get_port(mstb, port_msg->port_number);
1023 if (!port) {
1024 port = kzalloc(sizeof(*port), GFP_KERNEL);
1025 if (!port)
1026 return;
1027 kref_init(&port->kref);
1028 port->parent = mstb;
1029 port->port_num = port_msg->port_number;
1030 port->mgr = mstb->mgr;
1031 port->aux.name = "DPMST";
1032 port->aux.dev = dev;
1033 created = true;
1034 } else {
1035 old_pdt = port->pdt;
1036 old_ddps = port->ddps;
1037 }
1038
1039 port->pdt = port_msg->peer_device_type;
1040 port->input = port_msg->input_port;
1041 port->mcs = port_msg->mcs;
1042 port->ddps = port_msg->ddps;
1043 port->ldps = port_msg->legacy_device_plug_status;
1044 port->dpcd_rev = port_msg->dpcd_revision;
1045 port->num_sdp_streams = port_msg->num_sdp_streams;
1046 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1047 memcpy(port->guid, port_msg->peer_guid, 16);
1048
1049 /* manage mstb port lists with mgr lock - take a reference
1050 for this list */
1051 if (created) {
1052 mutex_lock(&mstb->mgr->lock);
1053 kref_get(&port->kref);
1054 list_add(&port->next, &mstb->ports);
1055 mutex_unlock(&mstb->mgr->lock);
1056 }
1057
1058 if (old_ddps != port->ddps) {
1059 if (port->ddps) {
1060 drm_dp_check_port_guid(mstb, port);
1061 if (!port->input)
1062 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1063 } else {
1064 port->guid_valid = false;
1065 port->available_pbn = 0;
1066 }
1067 }
1068
1069 if (old_pdt != port->pdt && !port->input) {
1070 drm_dp_port_teardown_pdt(port, old_pdt);
1071
1072 ret = drm_dp_port_setup_pdt(port);
1073 if (ret == true) {
1074 drm_dp_send_link_address(mstb->mgr, port->mstb);
1075 port->mstb->link_address_sent = true;
1076 }
1077 }
1078
1079 if (created && !port->input) {
1080 char proppath[255];
1081 build_mst_prop_path(port, mstb, proppath);
1082 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1083 }
1084
1085 /* put reference to this port */
1086 drm_dp_put_port(port);
1087}
1088
1089static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1090 struct drm_dp_connection_status_notify *conn_stat)
1091{
1092 struct drm_dp_mst_port *port;
1093 int old_pdt;
1094 int old_ddps;
1095 bool dowork = false;
1096 port = drm_dp_get_port(mstb, conn_stat->port_number);
1097 if (!port)
1098 return;
1099
1100 old_ddps = port->ddps;
1101 old_pdt = port->pdt;
1102 port->pdt = conn_stat->peer_device_type;
1103 port->mcs = conn_stat->message_capability_status;
1104 port->ldps = conn_stat->legacy_device_plug_status;
1105 port->ddps = conn_stat->displayport_device_plug_status;
1106
1107 if (old_ddps != port->ddps) {
1108 if (port->ddps) {
1109 drm_dp_check_port_guid(mstb, port);
1110 dowork = true;
1111 } else {
1112 port->guid_valid = false;
1113 port->available_pbn = 0;
1114 }
1115 }
1116 if (old_pdt != port->pdt && !port->input) {
1117 drm_dp_port_teardown_pdt(port, old_pdt);
1118
1119 if (drm_dp_port_setup_pdt(port))
1120 dowork = true;
1121 }
1122
1123 drm_dp_put_port(port);
1124 if (dowork)
1125 queue_work(system_long_wq, &mstb->mgr->work);
1126
1127}
1128
1129static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1130 u8 lct, u8 *rad)
1131{
1132 struct drm_dp_mst_branch *mstb;
1133 struct drm_dp_mst_port *port;
1134 int i;
1135 /* find the port by iterating down */
1136 mstb = mgr->mst_primary;
1137
1138 for (i = 0; i < lct - 1; i++) {
1139 int shift = (i % 2) ? 0 : 4;
1140 int port_num = rad[i / 2] >> shift;
1141
1142 list_for_each_entry(port, &mstb->ports, next) {
1143 if (port->port_num == port_num) {
1144 if (!port->mstb) {
1145 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1146 return NULL;
1147 }
1148
1149 mstb = port->mstb;
1150 break;
1151 }
1152 }
1153 }
1154 kref_get(&mstb->kref);
1155 return mstb;
1156}
1157
1158static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1159 struct drm_dp_mst_branch *mstb)
1160{
1161 struct drm_dp_mst_port *port;
1162
1163 if (!mstb->link_address_sent) {
1164 drm_dp_send_link_address(mgr, mstb);
1165 mstb->link_address_sent = true;
1166 }
1167 list_for_each_entry(port, &mstb->ports, next) {
1168 if (port->input)
1169 continue;
1170
1171 if (!port->ddps)
1172 continue;
1173
1174 if (!port->available_pbn)
1175 drm_dp_send_enum_path_resources(mgr, mstb, port);
1176
1177 if (port->mstb)
1178 drm_dp_check_and_send_link_address(mgr, port->mstb);
1179 }
1180}
1181
1182static void drm_dp_mst_link_probe_work(struct work_struct *work)
1183{
1184 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1185
1186 drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
1187
1188}
1189
1190static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1191 u8 *guid)
1192{
1193 static u8 zero_guid[16];
1194
1195 if (!memcmp(guid, zero_guid, 16)) {
1196 u64 salt = get_jiffies_64();
1197 memcpy(&guid[0], &salt, sizeof(u64));
1198 memcpy(&guid[8], &salt, sizeof(u64));
1199 return false;
1200 }
1201 return true;
1202}
1203
1204#if 0
1205static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1206{
1207 struct drm_dp_sideband_msg_req_body req;
1208
1209 req.req_type = DP_REMOTE_DPCD_READ;
1210 req.u.dpcd_read.port_number = port_num;
1211 req.u.dpcd_read.dpcd_address = offset;
1212 req.u.dpcd_read.num_bytes = num_bytes;
1213 drm_dp_encode_sideband_req(&req, msg);
1214
1215 return 0;
1216}
1217#endif
1218
1219static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1220 bool up, u8 *msg, int len)
1221{
1222 int ret;
1223 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1224 int tosend, total, offset;
1225 int retries = 0;
1226
1227retry:
1228 total = len;
1229 offset = 0;
1230 do {
1231 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1232
1233 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1234 &msg[offset],
1235 tosend);
1236 if (ret != tosend) {
1237 if (ret == -EIO && retries < 5) {
1238 retries++;
1239 goto retry;
1240 }
1241 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1242 WARN(1, "fail\n");
1243
1244 return -EIO;
1245 }
1246 offset += tosend;
1247 total -= tosend;
1248 } while (total > 0);
1249 return 0;
1250}
1251
1252static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1253 struct drm_dp_sideband_msg_tx *txmsg)
1254{
1255 struct drm_dp_mst_branch *mstb = txmsg->dst;
1256
1257 /* both msg slots are full */
1258 if (txmsg->seqno == -1) {
1259 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1260 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1261 return -EAGAIN;
1262 }
1263 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1264 txmsg->seqno = mstb->last_seqno;
1265 mstb->last_seqno ^= 1;
1266 } else if (mstb->tx_slots[0] == NULL)
1267 txmsg->seqno = 0;
1268 else
1269 txmsg->seqno = 1;
1270 mstb->tx_slots[txmsg->seqno] = txmsg;
1271 }
1272 hdr->broadcast = 0;
1273 hdr->path_msg = txmsg->path_msg;
1274 hdr->lct = mstb->lct;
1275 hdr->lcr = mstb->lct - 1;
1276 if (mstb->lct > 1)
1277 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1278 hdr->seqno = txmsg->seqno;
1279 return 0;
1280}
1281/*
1282 * process a single block of the next message in the sideband queue
1283 */
1284static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1285 struct drm_dp_sideband_msg_tx *txmsg,
1286 bool up)
1287{
1288 u8 chunk[48];
1289 struct drm_dp_sideband_msg_hdr hdr;
1290 int len, space, idx, tosend;
1291 int ret;
1292
1293 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1294 txmsg->seqno = -1;
1295 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1296 }
1297
1298 /* make hdr from dst mst - for replies use seqno
1299 otherwise assign one */
1300 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1301 if (ret < 0)
1302 return ret;
1303
1304 /* amount left to send in this message */
1305 len = txmsg->cur_len - txmsg->cur_offset;
1306
1307 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1308 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1309
1310 tosend = min(len, space);
1311 if (len == txmsg->cur_len)
1312 hdr.somt = 1;
1313 if (space >= len)
1314 hdr.eomt = 1;
1315
1316
1317 hdr.msg_len = tosend + 1;
1318 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1319 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1320 /* add crc at end */
1321 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1322 idx += tosend + 1;
1323
1324 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1325 if (ret) {
1326 DRM_DEBUG_KMS("sideband msg failed to send\n");
1327 return ret;
1328 }
1329
1330 txmsg->cur_offset += tosend;
1331 if (txmsg->cur_offset == txmsg->cur_len) {
1332 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1333 return 1;
1334 }
1335 return 0;
1336}
1337
1338/* must be called holding qlock */
1339static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1340{
1341 struct drm_dp_sideband_msg_tx *txmsg;
1342 int ret;
1343
1344 /* construct a chunk from the first msg in the tx_msg queue */
1345 if (list_empty(&mgr->tx_msg_downq)) {
1346 mgr->tx_down_in_progress = false;
1347 return;
1348 }
1349 mgr->tx_down_in_progress = true;
1350
1351 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1352 ret = process_single_tx_qlock(mgr, txmsg, false);
1353 if (ret == 1) {
1354 /* txmsg is sent it should be in the slots now */
1355 list_del(&txmsg->next);
1356 } else if (ret) {
1357 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1358 list_del(&txmsg->next);
1359 if (txmsg->seqno != -1)
1360 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1361 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1362 wake_up(&mgr->tx_waitq);
1363 }
1364 if (list_empty(&mgr->tx_msg_downq)) {
1365 mgr->tx_down_in_progress = false;
1366 return;
1367 }
1368}
1369
1370/* called holding qlock */
1371static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1372{
1373 struct drm_dp_sideband_msg_tx *txmsg;
1374 int ret;
1375
1376 /* construct a chunk from the first msg in the tx_msg queue */
1377 if (list_empty(&mgr->tx_msg_upq)) {
1378 mgr->tx_up_in_progress = false;
1379 return;
1380 }
1381
1382 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1383 ret = process_single_tx_qlock(mgr, txmsg, true);
1384 if (ret == 1) {
1385 /* up txmsgs aren't put in slots - so free after we send it */
1386 list_del(&txmsg->next);
1387 kfree(txmsg);
1388 } else if (ret)
1389 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1390 mgr->tx_up_in_progress = true;
1391}
1392
1393static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1394 struct drm_dp_sideband_msg_tx *txmsg)
1395{
1396 mutex_lock(&mgr->qlock);
1397 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1398 if (!mgr->tx_down_in_progress)
1399 process_single_down_tx_qlock(mgr);
1400 mutex_unlock(&mgr->qlock);
1401}
1402
1403static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1404 struct drm_dp_mst_branch *mstb)
1405{
1406 int len;
1407 struct drm_dp_sideband_msg_tx *txmsg;
1408 int ret;
1409
1410 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1411 if (!txmsg)
1412 return -ENOMEM;
1413
1414 txmsg->dst = mstb;
1415 len = build_link_address(txmsg);
1416
1417 drm_dp_queue_down_tx(mgr, txmsg);
1418
1419 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1420 if (ret > 0) {
1421 int i;
1422
1423 if (txmsg->reply.reply_type == 1)
1424 DRM_DEBUG_KMS("link address nak received\n");
1425 else {
1426 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1427 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1428 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,
1429 txmsg->reply.u.link_addr.ports[i].input_port,
1430 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1431 txmsg->reply.u.link_addr.ports[i].port_number,
1432 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1433 txmsg->reply.u.link_addr.ports[i].mcs,
1434 txmsg->reply.u.link_addr.ports[i].ddps,
1435 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1436 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1437 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1438 }
1439 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1440 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1441 }
1442 (*mgr->cbs->hotplug)(mgr);
1443 }
1444 } else
1445 DRM_DEBUG_KMS("link address failed %d\n", ret);
1446
1447 kfree(txmsg);
1448 return 0;
1449}
1450
1451static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1452 struct drm_dp_mst_branch *mstb,
1453 struct drm_dp_mst_port *port)
1454{
1455 int len;
1456 struct drm_dp_sideband_msg_tx *txmsg;
1457 int ret;
1458
1459 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1460 if (!txmsg)
1461 return -ENOMEM;
1462
1463 txmsg->dst = mstb;
1464 len = build_enum_path_resources(txmsg, port->port_num);
1465
1466 drm_dp_queue_down_tx(mgr, txmsg);
1467
1468 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1469 if (ret > 0) {
1470 if (txmsg->reply.reply_type == 1)
1471 DRM_DEBUG_KMS("enum path resources nak received\n");
1472 else {
1473 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1474 DRM_ERROR("got incorrect port in response\n");
1475 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,
1476 txmsg->reply.u.path_resources.avail_payload_bw_number);
1477 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1478 }
1479 }
1480
1481 kfree(txmsg);
1482 return 0;
1483}
1484
1485int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1486 struct drm_dp_mst_port *port,
1487 int id,
1488 int pbn)
1489{
1490 struct drm_dp_sideband_msg_tx *txmsg;
1491 struct drm_dp_mst_branch *mstb;
1492 int len, ret;
1493
1494 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1495 if (!mstb)
1496 return -EINVAL;
1497
1498 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1499 if (!txmsg) {
1500 ret = -ENOMEM;
1501 goto fail_put;
1502 }
1503
1504 txmsg->dst = mstb;
1505 len = build_allocate_payload(txmsg, port->port_num,
1506 id,
1507 pbn);
1508
1509 drm_dp_queue_down_tx(mgr, txmsg);
1510
1511 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1512 if (ret > 0) {
1513 if (txmsg->reply.reply_type == 1) {
1514 ret = -EINVAL;
1515 } else
1516 ret = 0;
1517 }
1518 kfree(txmsg);
1519fail_put:
1520 drm_dp_put_mst_branch_device(mstb);
1521 return ret;
1522}
1523
1524static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1525 int id,
1526 struct drm_dp_payload *payload)
1527{
1528 int ret;
1529
1530 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1531 if (ret < 0) {
1532 payload->payload_state = 0;
1533 return ret;
1534 }
1535 payload->payload_state = DP_PAYLOAD_LOCAL;
1536 return 0;
1537}
1538
1539int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1540 struct drm_dp_mst_port *port,
1541 int id,
1542 struct drm_dp_payload *payload)
1543{
1544 int ret;
1545 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1546 if (ret < 0)
1547 return ret;
1548 payload->payload_state = DP_PAYLOAD_REMOTE;
1549 return ret;
1550}
1551
1552int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1553 struct drm_dp_mst_port *port,
1554 int id,
1555 struct drm_dp_payload *payload)
1556{
1557 DRM_DEBUG_KMS("\n");
1558 /* its okay for these to fail */
1559 if (port) {
1560 drm_dp_payload_send_msg(mgr, port, id, 0);
1561 }
1562
1563 drm_dp_dpcd_write_payload(mgr, id, payload);
1564 payload->payload_state = 0;
1565 return 0;
1566}
1567
1568int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1569 int id,
1570 struct drm_dp_payload *payload)
1571{
1572 payload->payload_state = 0;
1573 return 0;
1574}
1575
1576/**
1577 * drm_dp_update_payload_part1() - Execute payload update part 1
1578 * @mgr: manager to use.
1579 *
1580 * This iterates over all proposed virtual channels, and tries to
1581 * allocate space in the link for them. For 0->slots transitions,
1582 * this step just writes the VCPI to the MST device. For slots->0
1583 * transitions, this writes the updated VCPIs and removes the
1584 * remote VC payloads.
1585 *
1586 * after calling this the driver should generate ACT and payload
1587 * packets.
1588 */
1589int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1590{
1591 int i;
1592 int cur_slots = 1;
1593 struct drm_dp_payload req_payload;
1594 struct drm_dp_mst_port *port;
1595
1596 mutex_lock(&mgr->payload_lock);
1597 for (i = 0; i < mgr->max_payloads; i++) {
1598 /* solve the current payloads - compare to the hw ones
1599 - update the hw view */
1600 req_payload.start_slot = cur_slots;
1601 if (mgr->proposed_vcpis[i]) {
1602 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1603 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1604 } else {
1605 port = NULL;
1606 req_payload.num_slots = 0;
1607 }
1608 /* work out what is required to happen with this payload */
1609 if (mgr->payloads[i].start_slot != req_payload.start_slot ||
1610 mgr->payloads[i].num_slots != req_payload.num_slots) {
1611
1612 /* need to push an update for this payload */
1613 if (req_payload.num_slots) {
1614 drm_dp_create_payload_step1(mgr, i + 1, &req_payload);
1615 mgr->payloads[i].num_slots = req_payload.num_slots;
1616 } else if (mgr->payloads[i].num_slots) {
1617 mgr->payloads[i].num_slots = 0;
1618 drm_dp_destroy_payload_step1(mgr, port, i + 1, &mgr->payloads[i]);
1619 req_payload.payload_state = mgr->payloads[i].payload_state;
1620 } else
1621 req_payload.payload_state = 0;
1622
1623 mgr->payloads[i].start_slot = req_payload.start_slot;
1624 mgr->payloads[i].payload_state = req_payload.payload_state;
1625 }
1626 cur_slots += req_payload.num_slots;
1627 }
1628 mutex_unlock(&mgr->payload_lock);
1629
1630 return 0;
1631}
1632EXPORT_SYMBOL(drm_dp_update_payload_part1);
1633
1634/**
1635 * drm_dp_update_payload_part2() - Execute payload update part 2
1636 * @mgr: manager to use.
1637 *
1638 * This iterates over all proposed virtual channels, and tries to
1639 * allocate space in the link for them. For 0->slots transitions,
1640 * this step writes the remote VC payload commands. For slots->0
1641 * this just resets some internal state.
1642 */
1643int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1644{
1645 struct drm_dp_mst_port *port;
1646 int i;
1647 int ret;
1648 mutex_lock(&mgr->payload_lock);
1649 for (i = 0; i < mgr->max_payloads; i++) {
1650
1651 if (!mgr->proposed_vcpis[i])
1652 continue;
1653
1654 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1655
1656 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1657 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1658 ret = drm_dp_create_payload_step2(mgr, port, i + 1, &mgr->payloads[i]);
1659 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1660 ret = drm_dp_destroy_payload_step2(mgr, i + 1, &mgr->payloads[i]);
1661 }
1662 if (ret) {
1663 mutex_unlock(&mgr->payload_lock);
1664 return ret;
1665 }
1666 }
1667 mutex_unlock(&mgr->payload_lock);
1668 return 0;
1669}
1670EXPORT_SYMBOL(drm_dp_update_payload_part2);
1671
1672#if 0 /* unused as of yet */
1673static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1674 struct drm_dp_mst_port *port,
1675 int offset, int size)
1676{
1677 int len;
1678 struct drm_dp_sideband_msg_tx *txmsg;
1679
1680 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1681 if (!txmsg)
1682 return -ENOMEM;
1683
1684 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1685 txmsg->dst = port->parent;
1686
1687 drm_dp_queue_down_tx(mgr, txmsg);
1688
1689 return 0;
1690}
1691#endif
1692
1693static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1694 struct drm_dp_mst_port *port,
1695 int offset, int size, u8 *bytes)
1696{
1697 int len;
1698 int ret;
1699 struct drm_dp_sideband_msg_tx *txmsg;
1700 struct drm_dp_mst_branch *mstb;
1701
1702 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1703 if (!mstb)
1704 return -EINVAL;
1705
1706 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1707 if (!txmsg) {
1708 ret = -ENOMEM;
1709 goto fail_put;
1710 }
1711
1712 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1713 txmsg->dst = mstb;
1714
1715 drm_dp_queue_down_tx(mgr, txmsg);
1716
1717 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1718 if (ret > 0) {
1719 if (txmsg->reply.reply_type == 1) {
1720 ret = -EINVAL;
1721 } else
1722 ret = 0;
1723 }
1724 kfree(txmsg);
1725fail_put:
1726 drm_dp_put_mst_branch_device(mstb);
1727 return ret;
1728}
1729
1730static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1731{
1732 struct drm_dp_sideband_msg_reply_body reply;
1733
1734 reply.reply_type = 1;
1735 reply.req_type = req_type;
1736 drm_dp_encode_sideband_reply(&reply, msg);
1737 return 0;
1738}
1739
1740static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1741 struct drm_dp_mst_branch *mstb,
1742 int req_type, int seqno, bool broadcast)
1743{
1744 struct drm_dp_sideband_msg_tx *txmsg;
1745
1746 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1747 if (!txmsg)
1748 return -ENOMEM;
1749
1750 txmsg->dst = mstb;
1751 txmsg->seqno = seqno;
1752 drm_dp_encode_up_ack_reply(txmsg, req_type);
1753
1754 mutex_lock(&mgr->qlock);
1755 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1756 if (!mgr->tx_up_in_progress) {
1757 process_single_up_tx_qlock(mgr);
1758 }
1759 mutex_unlock(&mgr->qlock);
1760 return 0;
1761}
1762
1763static int drm_dp_get_vc_payload_bw(int dp_link_bw, int dp_link_count)
1764{
1765 switch (dp_link_bw) {
1766 case DP_LINK_BW_1_62:
1767 return 3 * dp_link_count;
1768 case DP_LINK_BW_2_7:
1769 return 5 * dp_link_count;
1770 case DP_LINK_BW_5_4:
1771 return 10 * dp_link_count;
1772 }
1773 return 0;
1774}
1775
1776/**
1777 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1778 * @mgr: manager to set state for
1779 * @mst_state: true to enable MST on this connector - false to disable.
1780 *
1781 * This is called by the driver when it detects an MST capable device plugged
1782 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1783 */
1784int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1785{
1786 int ret = 0;
1787 struct drm_dp_mst_branch *mstb = NULL;
1788
1789 mutex_lock(&mgr->lock);
1790 if (mst_state == mgr->mst_state)
1791 goto out_unlock;
1792
1793 mgr->mst_state = mst_state;
1794 /* set the device into MST mode */
1795 if (mst_state) {
1796 WARN_ON(mgr->mst_primary);
1797
1798 /* get dpcd info */
1799 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1800 if (ret != DP_RECEIVER_CAP_SIZE) {
1801 DRM_DEBUG_KMS("failed to read DPCD\n");
1802 goto out_unlock;
1803 }
1804
1805 mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1], mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK);
1806 mgr->total_pbn = 2560;
1807 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1808 mgr->avail_slots = mgr->total_slots;
1809
1810 /* add initial branch device at LCT 1 */
1811 mstb = drm_dp_add_mst_branch_device(1, NULL);
1812 if (mstb == NULL) {
1813 ret = -ENOMEM;
1814 goto out_unlock;
1815 }
1816 mstb->mgr = mgr;
1817
1818 /* give this the main reference */
1819 mgr->mst_primary = mstb;
1820 kref_get(&mgr->mst_primary->kref);
1821
1822 {
1823 struct drm_dp_payload reset_pay;
1824 reset_pay.start_slot = 0;
1825 reset_pay.num_slots = 0x3f;
1826 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1827 }
1828
1829 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1830 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1831 if (ret < 0) {
1832 goto out_unlock;
1833 }
1834
1835
1836 /* sort out guid */
1837 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1838 if (ret != 16) {
1839 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1840 goto out_unlock;
1841 }
1842
1843 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1844 if (!mgr->guid_valid) {
1845 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1846 mgr->guid_valid = true;
1847 }
1848
1849 queue_work(system_long_wq, &mgr->work);
1850
1851 ret = 0;
1852 } else {
1853 /* disable MST on the device */
1854 mstb = mgr->mst_primary;
1855 mgr->mst_primary = NULL;
1856 /* this can fail if the device is gone */
1857 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1858 ret = 0;
1859 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1860 mgr->payload_mask = 0;
1861 set_bit(0, &mgr->payload_mask);
1862 }
1863
1864out_unlock:
1865 mutex_unlock(&mgr->lock);
1866 if (mstb)
1867 drm_dp_put_mst_branch_device(mstb);
1868 return ret;
1869
1870}
1871EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1872
1873/**
1874 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1875 * @mgr: manager to suspend
1876 *
1877 * This function tells the MST device that we can't handle UP messages
1878 * anymore. This should stop it from sending any since we are suspended.
1879 */
1880void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1881{
1882 mutex_lock(&mgr->lock);
1883 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1884 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1885 mutex_unlock(&mgr->lock);
1886}
1887EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1888
1889/**
1890 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1891 * @mgr: manager to resume
1892 *
1893 * This will fetch DPCD and see if the device is still there,
1894 * if it is, it will rewrite the MSTM control bits, and return.
1895 *
1896 * if the device fails this returns -1, and the driver should do
1897 * a full MST reprobe, in case we were undocked.
1898 */
1899int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1900{
1901 int ret = 0;
1902
1903 mutex_lock(&mgr->lock);
1904
1905 if (mgr->mst_primary) {
1906 int sret;
1907 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1908 if (sret != DP_RECEIVER_CAP_SIZE) {
1909 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1910 ret = -1;
1911 goto out_unlock;
1912 }
1913
1914 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1915 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1916 if (ret < 0) {
1917 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1918 ret = -1;
1919 goto out_unlock;
1920 }
1921 ret = 0;
1922 } else
1923 ret = -1;
1924
1925out_unlock:
1926 mutex_unlock(&mgr->lock);
1927 return ret;
1928}
1929EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
1930
1931static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
1932{
1933 int len;
1934 u8 replyblock[32];
1935 int replylen, origlen, curreply;
1936 int ret;
1937 struct drm_dp_sideband_msg_rx *msg;
1938 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
1939 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
1940
1941 len = min(mgr->max_dpcd_transaction_bytes, 16);
1942 ret = drm_dp_dpcd_read(mgr->aux, basereg,
1943 replyblock, len);
1944 if (ret != len) {
1945 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
1946 return;
1947 }
1948 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
1949 if (!ret) {
1950 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
1951 return;
1952 }
1953 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
1954
1955 origlen = replylen;
1956 replylen -= len;
1957 curreply = len;
1958 while (replylen > 0) {
1959 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
1960 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
1961 replyblock, len);
1962 if (ret != len) {
1963 DRM_DEBUG_KMS("failed to read a chunk\n");
1964 }
1965 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
1966 if (ret == false)
1967 DRM_DEBUG_KMS("failed to build sideband msg\n");
1968 curreply += len;
1969 replylen -= len;
1970 }
1971}
1972
1973static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
1974{
1975 int ret = 0;
1976
1977 drm_dp_get_one_sb_msg(mgr, false);
1978
1979 if (mgr->down_rep_recv.have_eomt) {
1980 struct drm_dp_sideband_msg_tx *txmsg;
1981 struct drm_dp_mst_branch *mstb;
1982 int slot = -1;
1983 mstb = drm_dp_get_mst_branch_device(mgr,
1984 mgr->down_rep_recv.initial_hdr.lct,
1985 mgr->down_rep_recv.initial_hdr.rad);
1986
1987 if (!mstb) {
1988 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
1989 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
1990 return 0;
1991 }
1992
1993 /* find the message */
1994 slot = mgr->down_rep_recv.initial_hdr.seqno;
1995 mutex_lock(&mgr->qlock);
1996 txmsg = mstb->tx_slots[slot];
1997 /* remove from slots */
1998 mutex_unlock(&mgr->qlock);
1999
2000 if (!txmsg) {
2001 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2002 mstb,
2003 mgr->down_rep_recv.initial_hdr.seqno,
2004 mgr->down_rep_recv.initial_hdr.lct,
2005 mgr->down_rep_recv.initial_hdr.rad[0],
2006 mgr->down_rep_recv.msg[0]);
2007 drm_dp_put_mst_branch_device(mstb);
2008 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2009 return 0;
2010 }
2011
2012 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2013 if (txmsg->reply.reply_type == 1) {
2014 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);
2015 }
2016
2017 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2018 drm_dp_put_mst_branch_device(mstb);
2019
2020 mutex_lock(&mgr->qlock);
2021 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2022 mstb->tx_slots[slot] = NULL;
2023 mutex_unlock(&mgr->qlock);
2024
2025 wake_up(&mgr->tx_waitq);
2026 }
2027 return ret;
2028}
2029
2030static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2031{
2032 int ret = 0;
2033 drm_dp_get_one_sb_msg(mgr, true);
2034
2035 if (mgr->up_req_recv.have_eomt) {
2036 struct drm_dp_sideband_msg_req_body msg;
2037 struct drm_dp_mst_branch *mstb;
2038 bool seqno;
2039 mstb = drm_dp_get_mst_branch_device(mgr,
2040 mgr->up_req_recv.initial_hdr.lct,
2041 mgr->up_req_recv.initial_hdr.rad);
2042 if (!mstb) {
2043 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2044 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2045 return 0;
2046 }
2047
2048 seqno = mgr->up_req_recv.initial_hdr.seqno;
2049 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2050
2051 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2052 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2053 drm_dp_update_port(mstb, &msg.u.conn_stat);
2054 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);
2055 (*mgr->cbs->hotplug)(mgr);
2056
2057 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2058 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2059 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2060 }
2061
2062 drm_dp_put_mst_branch_device(mstb);
2063 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2064 }
2065 return ret;
2066}
2067
2068/**
2069 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2070 * @mgr: manager to notify irq for.
2071 * @esi: 4 bytes from SINK_COUNT_ESI
2072 *
2073 * This should be called from the driver when it detects a short IRQ,
2074 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2075 * topology manager will process the sideband messages received as a result
2076 * of this.
2077 */
2078int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2079{
2080 int ret = 0;
2081 int sc;
2082 *handled = false;
2083 sc = esi[0] & 0x3f;
2084
2085 if (sc != mgr->sink_count) {
2086 mgr->sink_count = sc;
2087 *handled = true;
2088 }
2089
2090 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2091 ret = drm_dp_mst_handle_down_rep(mgr);
2092 *handled = true;
2093 }
2094
2095 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2096 ret |= drm_dp_mst_handle_up_req(mgr);
2097 *handled = true;
2098 }
2099
2100 drm_dp_mst_kick_tx(mgr);
2101 return ret;
2102}
2103EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2104
2105/**
2106 * drm_dp_mst_detect_port() - get connection status for an MST port
2107 * @mgr: manager for this port
2108 * @port: unverified pointer to a port
2109 *
2110 * This returns the current connection state for a port. It validates the
2111 * port pointer still exists so the caller doesn't require a reference
2112 */
2113enum drm_connector_status drm_dp_mst_detect_port(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2114{
2115 enum drm_connector_status status = connector_status_disconnected;
2116
2117 /* we need to search for the port in the mgr in case its gone */
2118 port = drm_dp_get_validated_port_ref(mgr, port);
2119 if (!port)
2120 return connector_status_disconnected;
2121
2122 if (!port->ddps)
2123 goto out;
2124
2125 switch (port->pdt) {
2126 case DP_PEER_DEVICE_NONE:
2127 case DP_PEER_DEVICE_MST_BRANCHING:
2128 break;
2129
2130 case DP_PEER_DEVICE_SST_SINK:
2131 status = connector_status_connected;
2132 break;
2133 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2134 if (port->ldps)
2135 status = connector_status_connected;
2136 break;
2137 }
2138out:
2139 drm_dp_put_port(port);
2140 return status;
2141}
2142EXPORT_SYMBOL(drm_dp_mst_detect_port);
2143
2144/**
2145 * drm_dp_mst_get_edid() - get EDID for an MST port
2146 * @connector: toplevel connector to get EDID for
2147 * @mgr: manager for this port
2148 * @port: unverified pointer to a port.
2149 *
2150 * This returns an EDID for the port connected to a connector,
2151 * It validates the pointer still exists so the caller doesn't require a
2152 * reference.
2153 */
2154struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2155{
2156 struct edid *edid = NULL;
2157
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);
2160 if (!port)
2161 return NULL;
2162
2163 edid = drm_get_edid(connector, &port->aux.ddc);
2164 drm_dp_put_port(port);
2165 return edid;
2166}
2167EXPORT_SYMBOL(drm_dp_mst_get_edid);
2168
2169/**
2170 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2171 * @mgr: manager to use
2172 * @pbn: payload bandwidth to convert into slots.
2173 */
2174int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2175 int pbn)
2176{
2177 int num_slots;
2178
2179 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2180
2181 if (num_slots > mgr->avail_slots)
2182 return -ENOSPC;
2183 return num_slots;
2184}
2185EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2186
2187static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2188 struct drm_dp_vcpi *vcpi, int pbn)
2189{
2190 int num_slots;
2191 int ret;
2192
2193 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2194
2195 if (num_slots > mgr->avail_slots)
2196 return -ENOSPC;
2197
2198 vcpi->pbn = pbn;
2199 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2200 vcpi->num_slots = num_slots;
2201
2202 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2203 if (ret < 0)
2204 return ret;
2205 return 0;
2206}
2207
2208/**
2209 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2210 * @mgr: manager for this port
2211 * @port: port to allocate a virtual channel for.
2212 * @pbn: payload bandwidth number to request
2213 * @slots: returned number of slots for this PBN.
2214 */
2215bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2216{
2217 int ret;
2218
2219 port = drm_dp_get_validated_port_ref(mgr, port);
2220 if (!port)
2221 return false;
2222
2223 if (port->vcpi.vcpi > 0) {
2224 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2225 if (pbn == port->vcpi.pbn) {
2226 *slots = port->vcpi.num_slots;
2227 return true;
2228 }
2229 }
2230
2231 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2232 if (ret) {
2233 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2234 goto out;
2235 }
2236 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2237 *slots = port->vcpi.num_slots;
2238
2239 drm_dp_put_port(port);
2240 return true;
2241out:
2242 return false;
2243}
2244EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2245
2246/**
2247 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2248 * @mgr: manager for this port
2249 * @port: unverified pointer to a port.
2250 *
2251 * This just resets the number of slots for the ports VCPI for later programming.
2252 */
2253void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2254{
2255 port = drm_dp_get_validated_port_ref(mgr, port);
2256 if (!port)
2257 return;
2258 port->vcpi.num_slots = 0;
2259 drm_dp_put_port(port);
2260}
2261EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2262
2263/**
2264 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2265 * @mgr: manager for this port
2266 * @port: unverified port to deallocate vcpi for
2267 */
2268void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2269{
2270 port = drm_dp_get_validated_port_ref(mgr, port);
2271 if (!port)
2272 return;
2273
2274 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2275 port->vcpi.num_slots = 0;
2276 port->vcpi.pbn = 0;
2277 port->vcpi.aligned_pbn = 0;
2278 port->vcpi.vcpi = 0;
2279 drm_dp_put_port(port);
2280}
2281EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2282
2283static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2284 int id, struct drm_dp_payload *payload)
2285{
2286 u8 payload_alloc[3], status;
2287 int ret;
2288 int retries = 0;
2289
2290 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2291 DP_PAYLOAD_TABLE_UPDATED);
2292
2293 payload_alloc[0] = id;
2294 payload_alloc[1] = payload->start_slot;
2295 payload_alloc[2] = payload->num_slots;
2296
2297 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2298 if (ret != 3) {
2299 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2300 goto fail;
2301 }
2302
2303retry:
2304 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2305 if (ret < 0) {
2306 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2307 goto fail;
2308 }
2309
2310 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2311 retries++;
2312 if (retries < 20) {
2313 usleep_range(10000, 20000);
2314 goto retry;
2315 }
2316 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2317 ret = -EINVAL;
2318 goto fail;
2319 }
2320 ret = 0;
2321fail:
2322 return ret;
2323}
2324
2325
2326/**
2327 * drm_dp_check_act_status() - Check ACT handled status.
2328 * @mgr: manager to use
2329 *
2330 * Check the payload status bits in the DPCD for ACT handled completion.
2331 */
2332int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2333{
2334 u8 status;
2335 int ret;
2336 int count = 0;
2337
2338 do {
2339 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2340
2341 if (ret < 0) {
2342 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2343 goto fail;
2344 }
2345
2346 if (status & DP_PAYLOAD_ACT_HANDLED)
2347 break;
2348 count++;
2349 udelay(100);
2350
2351 } while (count < 30);
2352
2353 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2354 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2355 ret = -EINVAL;
2356 goto fail;
2357 }
2358 return 0;
2359fail:
2360 return ret;
2361}
2362EXPORT_SYMBOL(drm_dp_check_act_status);
2363
2364/**
2365 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2366 * @clock: dot clock for the mode
2367 * @bpp: bpp for the mode.
2368 *
2369 * This uses the formula in the spec to calculate the PBN value for a mode.
2370 */
2371int drm_dp_calc_pbn_mode(int clock, int bpp)
2372{
2373 fixed20_12 pix_bw;
2374 fixed20_12 fbpp;
2375 fixed20_12 result;
2376 fixed20_12 margin, tmp;
2377 u32 res;
2378
2379 pix_bw.full = dfixed_const(clock);
2380 fbpp.full = dfixed_const(bpp);
2381 tmp.full = dfixed_const(8);
2382 fbpp.full = dfixed_div(fbpp, tmp);
2383
2384 result.full = dfixed_mul(pix_bw, fbpp);
2385 margin.full = dfixed_const(54);
2386 tmp.full = dfixed_const(64);
2387 margin.full = dfixed_div(margin, tmp);
2388 result.full = dfixed_div(result, margin);
2389
2390 margin.full = dfixed_const(1006);
2391 tmp.full = dfixed_const(1000);
2392 margin.full = dfixed_div(margin, tmp);
2393 result.full = dfixed_mul(result, margin);
2394
2395 result.full = dfixed_div(result, tmp);
2396 result.full = dfixed_ceil(result);
2397 res = dfixed_trunc(result);
2398 return res;
2399}
2400EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2401
2402static int test_calc_pbn_mode(void)
2403{
2404 int ret;
2405 ret = drm_dp_calc_pbn_mode(154000, 30);
2406 if (ret != 689)
2407 return -EINVAL;
2408 ret = drm_dp_calc_pbn_mode(234000, 30);
2409 if (ret != 1047)
2410 return -EINVAL;
2411 return 0;
2412}
2413
2414/* we want to kick the TX after we've ack the up/down IRQs. */
2415static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2416{
2417 queue_work(system_long_wq, &mgr->tx_work);
2418}
2419
2420static void drm_dp_mst_dump_mstb(struct seq_file *m,
2421 struct drm_dp_mst_branch *mstb)
2422{
2423 struct drm_dp_mst_port *port;
2424 int tabs = mstb->lct;
2425 char prefix[10];
2426 int i;
2427
2428 for (i = 0; i < tabs; i++)
2429 prefix[i] = '\t';
2430 prefix[i] = '\0';
2431
2432 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2433 list_for_each_entry(port, &mstb->ports, next) {
2434 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2435 if (port->mstb)
2436 drm_dp_mst_dump_mstb(m, port->mstb);
2437 }
2438}
2439
2440static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2441 char *buf)
2442{
2443 int ret;
2444 int i;
2445 for (i = 0; i < 4; i++) {
2446 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2447 if (ret != 16)
2448 break;
2449 }
2450 if (i == 4)
2451 return true;
2452 return false;
2453}
2454
2455/**
2456 * drm_dp_mst_dump_topology(): dump topology to seq file.
2457 * @m: seq_file to dump output to
2458 * @mgr: manager to dump current topology for.
2459 *
2460 * helper to dump MST topology to a seq file for debugfs.
2461 */
2462void drm_dp_mst_dump_topology(struct seq_file *m,
2463 struct drm_dp_mst_topology_mgr *mgr)
2464{
2465 int i;
2466 struct drm_dp_mst_port *port;
2467 mutex_lock(&mgr->lock);
2468 if (mgr->mst_primary)
2469 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2470
2471 /* dump VCPIs */
2472 mutex_unlock(&mgr->lock);
2473
2474 mutex_lock(&mgr->payload_lock);
2475 seq_printf(m, "vcpi: %lx\n", mgr->payload_mask);
2476
2477 for (i = 0; i < mgr->max_payloads; i++) {
2478 if (mgr->proposed_vcpis[i]) {
2479 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2480 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2481 } else
2482 seq_printf(m, "vcpi %d:unsed\n", i);
2483 }
2484 for (i = 0; i < mgr->max_payloads; i++) {
2485 seq_printf(m, "payload %d: %d, %d, %d\n",
2486 i,
2487 mgr->payloads[i].payload_state,
2488 mgr->payloads[i].start_slot,
2489 mgr->payloads[i].num_slots);
2490
2491
2492 }
2493 mutex_unlock(&mgr->payload_lock);
2494
2495 mutex_lock(&mgr->lock);
2496 if (mgr->mst_primary) {
2497 u8 buf[64];
2498 bool bret;
2499 int ret;
2500 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2501 seq_printf(m, "dpcd: ");
2502 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2503 seq_printf(m, "%02x ", buf[i]);
2504 seq_printf(m, "\n");
2505 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2506 seq_printf(m, "faux/mst: ");
2507 for (i = 0; i < 2; i++)
2508 seq_printf(m, "%02x ", buf[i]);
2509 seq_printf(m, "\n");
2510 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2511 seq_printf(m, "mst ctrl: ");
2512 for (i = 0; i < 1; i++)
2513 seq_printf(m, "%02x ", buf[i]);
2514 seq_printf(m, "\n");
2515
2516 bret = dump_dp_payload_table(mgr, buf);
2517 if (bret == true) {
2518 seq_printf(m, "payload table: ");
2519 for (i = 0; i < 63; i++)
2520 seq_printf(m, "%02x ", buf[i]);
2521 seq_printf(m, "\n");
2522 }
2523
2524 }
2525
2526 mutex_unlock(&mgr->lock);
2527
2528}
2529EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2530
2531static void drm_dp_tx_work(struct work_struct *work)
2532{
2533 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2534
2535 mutex_lock(&mgr->qlock);
2536 if (mgr->tx_down_in_progress)
2537 process_single_down_tx_qlock(mgr);
2538 mutex_unlock(&mgr->qlock);
2539}
2540
2541/**
2542 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2543 * @mgr: manager struct to initialise
2544 * @dev: device providing this structure - for i2c addition.
2545 * @aux: DP helper aux channel to talk to this device
2546 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2547 * @max_payloads: maximum number of payloads this GPU can source
2548 * @conn_base_id: the connector object ID the MST device is connected to.
2549 *
2550 * Return 0 for success, or negative error code on failure
2551 */
2552int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2553 struct device *dev, struct drm_dp_aux *aux,
2554 int max_dpcd_transaction_bytes,
2555 int max_payloads, int conn_base_id)
2556{
2557 mutex_init(&mgr->lock);
2558 mutex_init(&mgr->qlock);
2559 mutex_init(&mgr->payload_lock);
2560 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2561 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2562 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2563 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2564 init_waitqueue_head(&mgr->tx_waitq);
2565 mgr->dev = dev;
2566 mgr->aux = aux;
2567 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2568 mgr->max_payloads = max_payloads;
2569 mgr->conn_base_id = conn_base_id;
2570 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2571 if (!mgr->payloads)
2572 return -ENOMEM;
2573 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2574 if (!mgr->proposed_vcpis)
2575 return -ENOMEM;
2576 set_bit(0, &mgr->payload_mask);
2577 test_calc_pbn_mode();
2578 return 0;
2579}
2580EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2581
2582/**
2583 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2584 * @mgr: manager to destroy
2585 */
2586void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2587{
2588 mutex_lock(&mgr->payload_lock);
2589 kfree(mgr->payloads);
2590 mgr->payloads = NULL;
2591 kfree(mgr->proposed_vcpis);
2592 mgr->proposed_vcpis = NULL;
2593 mutex_unlock(&mgr->payload_lock);
2594 mgr->dev = NULL;
2595 mgr->aux = NULL;
2596}
2597EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2598
2599/* I2C device */
2600static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2601 int num)
2602{
2603 struct drm_dp_aux *aux = adapter->algo_data;
2604 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2605 struct drm_dp_mst_branch *mstb;
2606 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2607 unsigned int i;
2608 bool reading = false;
2609 struct drm_dp_sideband_msg_req_body msg;
2610 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2611 int ret;
2612
2613 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2614 if (!mstb)
2615 return -EREMOTEIO;
2616
2617 /* construct i2c msg */
2618 /* see if last msg is a read */
2619 if (msgs[num - 1].flags & I2C_M_RD)
2620 reading = true;
2621
2622 if (!reading) {
2623 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2624 ret = -EIO;
2625 goto out;
2626 }
2627
2628 msg.req_type = DP_REMOTE_I2C_READ;
2629 msg.u.i2c_read.num_transactions = num - 1;
2630 msg.u.i2c_read.port_number = port->port_num;
2631 for (i = 0; i < num - 1; i++) {
2632 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2633 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2634 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2635 }
2636 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2637 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2638
2639 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2640 if (!txmsg) {
2641 ret = -ENOMEM;
2642 goto out;
2643 }
2644
2645 txmsg->dst = mstb;
2646 drm_dp_encode_sideband_req(&msg, txmsg);
2647
2648 drm_dp_queue_down_tx(mgr, txmsg);
2649
2650 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2651 if (ret > 0) {
2652
2653 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2654 ret = -EREMOTEIO;
2655 goto out;
2656 }
2657 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2658 ret = -EIO;
2659 goto out;
2660 }
2661 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2662 ret = num;
2663 }
2664out:
2665 kfree(txmsg);
2666 drm_dp_put_mst_branch_device(mstb);
2667 return ret;
2668}
2669
2670static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2671{
2672 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2673 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2674 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2675 I2C_FUNC_10BIT_ADDR;
2676}
2677
2678static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2679 .functionality = drm_dp_mst_i2c_functionality,
2680 .master_xfer = drm_dp_mst_i2c_xfer,
2681};
2682
2683/**
2684 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2685 * @aux: DisplayPort AUX channel
2686 *
2687 * Returns 0 on success or a negative error code on failure.
2688 */
2689static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2690{
2691 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2692 aux->ddc.algo_data = aux;
2693 aux->ddc.retries = 3;
2694
2695 aux->ddc.class = I2C_CLASS_DDC;
2696 aux->ddc.owner = THIS_MODULE;
2697 aux->ddc.dev.parent = aux->dev;
2698 aux->ddc.dev.of_node = aux->dev->of_node;
2699
2700 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2701 sizeof(aux->ddc.name));
2702
2703 return i2c_add_adapter(&aux->ddc);
2704}
2705
2706/**
2707 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2708 * @aux: DisplayPort AUX channel
2709 */
2710static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2711{
2712 i2c_del_adapter(&aux->ddc);
2713}
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