?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Linux 4.1.16
[linux/fpc-iii.git] / drivers / gpu / drm / drm_dp_mst_topology.c
blob109e776345d39c5b800bf20d956738cb9aca16a9
1 /*
2 * Copyright © 2014 Red Hat
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23 #include <linux/kernel.h>
24 #include <linux/delay.h>
25 #include <linux/init.h>
26 #include <linux/errno.h>
27 #include <linux/sched.h>
28 #include <linux/seq_file.h>
29 #include <linux/i2c.h>
30 #include <drm/drm_dp_mst_helper.h>
31 #include <drm/drmP.h>
32
33 #include <drm/drm_fixed.h>
34
35 /**
36 * DOC: dp mst helper
37 *
38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
39 * protocol. The helpers contain a topology manager and bandwidth manager.
40 * The helpers encapsulate the sending and received of sideband msgs.
41 */
42 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
43 char *buf);
44 static int test_calc_pbn_mode(void);
45
46 static void drm_dp_put_port(struct drm_dp_mst_port *port);
47
48 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
49 int id,
50 struct drm_dp_payload *payload);
51
52 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
53 struct drm_dp_mst_port *port,
54 int offset, int size, u8 *bytes);
55
56 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
57 struct drm_dp_mst_branch *mstb);
58 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
59 struct drm_dp_mst_branch *mstb,
60 struct drm_dp_mst_port *port);
61 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
62 u8 *guid);
63
64 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
65 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
66 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
67 /* sideband msg handling */
68 static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
69 {
70 u8 bitmask = 0x80;
71 u8 bitshift = 7;
72 u8 array_index = 0;
73 int number_of_bits = num_nibbles * 4;
74 u8 remainder = 0;
75
76 while (number_of_bits != 0) {
77 number_of_bits--;
78 remainder <<= 1;
79 remainder |= (data[array_index] & bitmask) >> bitshift;
80 bitmask >>= 1;
81 bitshift--;
82 if (bitmask == 0) {
83 bitmask = 0x80;
84 bitshift = 7;
85 array_index++;
86 }
87 if ((remainder & 0x10) == 0x10)
88 remainder ^= 0x13;
89 }
90
91 number_of_bits = 4;
92 while (number_of_bits != 0) {
93 number_of_bits--;
94 remainder <<= 1;
95 if ((remainder & 0x10) != 0)
96 remainder ^= 0x13;
97 }
98
99 return remainder;
100 }
101
102 static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
103 {
104 u8 bitmask = 0x80;
105 u8 bitshift = 7;
106 u8 array_index = 0;
107 int number_of_bits = number_of_bytes * 8;
108 u16 remainder = 0;
109
110 while (number_of_bits != 0) {
111 number_of_bits--;
112 remainder <<= 1;
113 remainder |= (data[array_index] & bitmask) >> bitshift;
114 bitmask >>= 1;
115 bitshift--;
116 if (bitmask == 0) {
117 bitmask = 0x80;
118 bitshift = 7;
119 array_index++;
120 }
121 if ((remainder & 0x100) == 0x100)
122 remainder ^= 0xd5;
123 }
124
125 number_of_bits = 8;
126 while (number_of_bits != 0) {
127 number_of_bits--;
128 remainder <<= 1;
129 if ((remainder & 0x100) != 0)
130 remainder ^= 0xd5;
131 }
132
133 return remainder & 0xff;
134 }
135 static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
136 {
137 u8 size = 3;
138 size += (hdr->lct / 2);
139 return size;
140 }
141
142 static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
143 u8 *buf, int *len)
144 {
145 int idx = 0;
146 int i;
147 u8 crc4;
148 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
149 for (i = 0; i < (hdr->lct / 2); i++)
150 buf[idx++] = hdr->rad[i];
151 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
152 (hdr->msg_len & 0x3f);
153 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
154
155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
156 buf[idx - 1] |= (crc4 & 0xf);
157
158 *len = idx;
159 }
160
161 static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
162 u8 *buf, int buflen, u8 *hdrlen)
163 {
164 u8 crc4;
165 u8 len;
166 int i;
167 u8 idx;
168 if (buf[0] == 0)
169 return false;
170 len = 3;
171 len += ((buf[0] & 0xf0) >> 4) / 2;
172 if (len > buflen)
173 return false;
174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
175
176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
178 return false;
179 }
180
181 hdr->lct = (buf[0] & 0xf0) >> 4;
182 hdr->lcr = (buf[0] & 0xf);
183 idx = 1;
184 for (i = 0; i < (hdr->lct / 2); i++)
185 hdr->rad[i] = buf[idx++];
186 hdr->broadcast = (buf[idx] >> 7) & 0x1;
187 hdr->path_msg = (buf[idx] >> 6) & 0x1;
188 hdr->msg_len = buf[idx] & 0x3f;
189 idx++;
190 hdr->somt = (buf[idx] >> 7) & 0x1;
191 hdr->eomt = (buf[idx] >> 6) & 0x1;
192 hdr->seqno = (buf[idx] >> 4) & 0x1;
193 idx++;
194 *hdrlen = idx;
195 return true;
196 }
197
198 static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
199 struct drm_dp_sideband_msg_tx *raw)
200 {
201 int idx = 0;
202 int i;
203 u8 *buf = raw->msg;
204 buf[idx++] = req->req_type & 0x7f;
205
206 switch (req->req_type) {
207 case DP_ENUM_PATH_RESOURCES:
208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
209 idx++;
210 break;
211 case DP_ALLOCATE_PAYLOAD:
212 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
213 (req->u.allocate_payload.number_sdp_streams & 0xf);
214 idx++;
215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
216 idx++;
217 buf[idx] = (req->u.allocate_payload.pbn >> 8);
218 idx++;
219 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
220 idx++;
221 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
222 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
223 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
224 idx++;
225 }
226 if (req->u.allocate_payload.number_sdp_streams & 1) {
227 i = req->u.allocate_payload.number_sdp_streams - 1;
228 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
229 idx++;
230 }
231 break;
232 case DP_QUERY_PAYLOAD:
233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
234 idx++;
235 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
236 idx++;
237 break;
238 case DP_REMOTE_DPCD_READ:
239 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
240 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
241 idx++;
242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
243 idx++;
244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
245 idx++;
246 buf[idx] = (req->u.dpcd_read.num_bytes);
247 idx++;
248 break;
249
250 case DP_REMOTE_DPCD_WRITE:
251 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
252 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
253 idx++;
254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
255 idx++;
256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
257 idx++;
258 buf[idx] = (req->u.dpcd_write.num_bytes);
259 idx++;
260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
261 idx += req->u.dpcd_write.num_bytes;
262 break;
263 case DP_REMOTE_I2C_READ:
264 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
265 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
266 idx++;
267 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
268 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
269 idx++;
270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
271 idx++;
272 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
273 idx += req->u.i2c_read.transactions[i].num_bytes;
274
275 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
276 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
277 idx++;
278 }
279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
280 idx++;
281 buf[idx] = (req->u.i2c_read.num_bytes_read);
282 idx++;
283 break;
284
285 case DP_REMOTE_I2C_WRITE:
286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
287 idx++;
288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
289 idx++;
290 buf[idx] = (req->u.i2c_write.num_bytes);
291 idx++;
292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
293 idx += req->u.i2c_write.num_bytes;
294 break;
295 }
296 raw->cur_len = idx;
297 }
298
299 static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
300 {
301 u8 crc4;
302 crc4 = drm_dp_msg_data_crc4(msg, len);
303 msg[len] = crc4;
304 }
305
306 static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
307 struct drm_dp_sideband_msg_tx *raw)
308 {
309 int idx = 0;
310 u8 *buf = raw->msg;
311
312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
313
314 raw->cur_len = idx;
315 }
316
317 /* this adds a chunk of msg to the builder to get the final msg */
318 static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
319 u8 *replybuf, u8 replybuflen, bool hdr)
320 {
321 int ret;
322 u8 crc4;
323
324 if (hdr) {
325 u8 hdrlen;
326 struct drm_dp_sideband_msg_hdr recv_hdr;
327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
328 if (ret == false) {
329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
330 return false;
331 }
332
333 /* get length contained in this portion */
334 msg->curchunk_len = recv_hdr.msg_len;
335 msg->curchunk_hdrlen = hdrlen;
336
337 /* we have already gotten an somt - don't bother parsing */
338 if (recv_hdr.somt && msg->have_somt)
339 return false;
340
341 if (recv_hdr.somt) {
342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
343 msg->have_somt = true;
344 }
345 if (recv_hdr.eomt)
346 msg->have_eomt = true;
347
348 /* copy the bytes for the remainder of this header chunk */
349 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
350 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
351 } else {
352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
353 msg->curchunk_idx += replybuflen;
354 }
355
356 if (msg->curchunk_idx >= msg->curchunk_len) {
357 /* do CRC */
358 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
359 /* copy chunk into bigger msg */
360 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
361 msg->curlen += msg->curchunk_len - 1;
362 }
363 return true;
364 }
365
366 static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
367 struct drm_dp_sideband_msg_reply_body *repmsg)
368 {
369 int idx = 1;
370 int i;
371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
372 idx += 16;
373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
374 idx++;
375 if (idx > raw->curlen)
376 goto fail_len;
377 for (i = 0; i < repmsg->u.link_addr.nports; i++) {
378 if (raw->msg[idx] & 0x80)
379 repmsg->u.link_addr.ports[i].input_port = 1;
380
381 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
382 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
383
384 idx++;
385 if (idx > raw->curlen)
386 goto fail_len;
387 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
388 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
389 if (repmsg->u.link_addr.ports[i].input_port == 0)
390 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
391 idx++;
392 if (idx > raw->curlen)
393 goto fail_len;
394 if (repmsg->u.link_addr.ports[i].input_port == 0) {
395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
396 idx++;
397 if (idx > raw->curlen)
398 goto fail_len;
399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
400 idx += 16;
401 if (idx > raw->curlen)
402 goto fail_len;
403 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
404 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
405 idx++;
406
407 }
408 if (idx > raw->curlen)
409 goto fail_len;
410 }
411
412 return true;
413 fail_len:
414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
415 return false;
416 }
417
418 static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
419 struct drm_dp_sideband_msg_reply_body *repmsg)
420 {
421 int idx = 1;
422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
423 idx++;
424 if (idx > raw->curlen)
425 goto fail_len;
426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
427 if (idx > raw->curlen)
428 goto fail_len;
429
430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
431 return true;
432 fail_len:
433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
434 return false;
435 }
436
437 static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
438 struct drm_dp_sideband_msg_reply_body *repmsg)
439 {
440 int idx = 1;
441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
442 idx++;
443 if (idx > raw->curlen)
444 goto fail_len;
445 return true;
446 fail_len:
447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
448 return false;
449 }
450
451 static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
452 struct drm_dp_sideband_msg_reply_body *repmsg)
453 {
454 int idx = 1;
455
456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
457 idx++;
458 if (idx > raw->curlen)
459 goto fail_len;
460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
461 idx++;
462 /* TODO check */
463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
464 return true;
465 fail_len:
466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
467 return false;
468 }
469
470 static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
471 struct drm_dp_sideband_msg_reply_body *repmsg)
472 {
473 int idx = 1;
474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
475 idx++;
476 if (idx > raw->curlen)
477 goto fail_len;
478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
479 idx += 2;
480 if (idx > raw->curlen)
481 goto fail_len;
482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
483 idx += 2;
484 if (idx > raw->curlen)
485 goto fail_len;
486 return true;
487 fail_len:
488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
489 return false;
490 }
491
492 static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
493 struct drm_dp_sideband_msg_reply_body *repmsg)
494 {
495 int idx = 1;
496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
497 idx++;
498 if (idx > raw->curlen)
499 goto fail_len;
500 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
501 idx++;
502 if (idx > raw->curlen)
503 goto fail_len;
504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
505 idx += 2;
506 if (idx > raw->curlen)
507 goto fail_len;
508 return true;
509 fail_len:
510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
511 return false;
512 }
513
514 static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
515 struct drm_dp_sideband_msg_reply_body *repmsg)
516 {
517 int idx = 1;
518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
519 idx++;
520 if (idx > raw->curlen)
521 goto fail_len;
522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
523 idx += 2;
524 if (idx > raw->curlen)
525 goto fail_len;
526 return true;
527 fail_len:
528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
529 return false;
530 }
531
532 static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
533 struct drm_dp_sideband_msg_reply_body *msg)
534 {
535 memset(msg, 0, sizeof(*msg));
536 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
537 msg->req_type = (raw->msg[0] & 0x7f);
538
539 if (msg->reply_type) {
540 memcpy(msg->u.nak.guid, &raw->msg[1], 16);
541 msg->u.nak.reason = raw->msg[17];
542 msg->u.nak.nak_data = raw->msg[18];
543 return false;
544 }
545
546 switch (msg->req_type) {
547 case DP_LINK_ADDRESS:
548 return drm_dp_sideband_parse_link_address(raw, msg);
549 case DP_QUERY_PAYLOAD:
550 return drm_dp_sideband_parse_query_payload_ack(raw, msg);
551 case DP_REMOTE_DPCD_READ:
552 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
553 case DP_REMOTE_DPCD_WRITE:
554 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
555 case DP_REMOTE_I2C_READ:
556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
557 case DP_ENUM_PATH_RESOURCES:
558 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
559 case DP_ALLOCATE_PAYLOAD:
560 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
561 default:
562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
563 return false;
564 }
565 }
566
567 static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
568 struct drm_dp_sideband_msg_req_body *msg)
569 {
570 int idx = 1;
571
572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
573 idx++;
574 if (idx > raw->curlen)
575 goto fail_len;
576
577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
578 idx += 16;
579 if (idx > raw->curlen)
580 goto fail_len;
581
582 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
583 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
584 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
585 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
586 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
587 idx++;
588 return true;
589 fail_len:
590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
591 return false;
592 }
593
594 static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
595 struct drm_dp_sideband_msg_req_body *msg)
596 {
597 int idx = 1;
598
599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
600 idx++;
601 if (idx > raw->curlen)
602 goto fail_len;
603
604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
605 idx += 16;
606 if (idx > raw->curlen)
607 goto fail_len;
608
609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
610 idx++;
611 return true;
612 fail_len:
613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
614 return false;
615 }
616
617 static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
618 struct drm_dp_sideband_msg_req_body *msg)
619 {
620 memset(msg, 0, sizeof(*msg));
621 msg->req_type = (raw->msg[0] & 0x7f);
622
623 switch (msg->req_type) {
624 case DP_CONNECTION_STATUS_NOTIFY:
625 return drm_dp_sideband_parse_connection_status_notify(raw, msg);
626 case DP_RESOURCE_STATUS_NOTIFY:
627 return drm_dp_sideband_parse_resource_status_notify(raw, msg);
628 default:
629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
630 return false;
631 }
632 }
633
634 static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
635 {
636 struct drm_dp_sideband_msg_req_body req;
637
638 req.req_type = DP_REMOTE_DPCD_WRITE;
639 req.u.dpcd_write.port_number = port_num;
640 req.u.dpcd_write.dpcd_address = offset;
641 req.u.dpcd_write.num_bytes = num_bytes;
642 req.u.dpcd_write.bytes = bytes;
643 drm_dp_encode_sideband_req(&req, msg);
644
645 return 0;
646 }
647
648 static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
649 {
650 struct drm_dp_sideband_msg_req_body req;
651
652 req.req_type = DP_LINK_ADDRESS;
653 drm_dp_encode_sideband_req(&req, msg);
654 return 0;
655 }
656
657 static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
658 {
659 struct drm_dp_sideband_msg_req_body req;
660
661 req.req_type = DP_ENUM_PATH_RESOURCES;
662 req.u.port_num.port_number = port_num;
663 drm_dp_encode_sideband_req(&req, msg);
664 msg->path_msg = true;
665 return 0;
666 }
667
668 static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
669 u8 vcpi, uint16_t pbn)
670 {
671 struct drm_dp_sideband_msg_req_body req;
672 memset(&req, 0, sizeof(req));
673 req.req_type = DP_ALLOCATE_PAYLOAD;
674 req.u.allocate_payload.port_number = port_num;
675 req.u.allocate_payload.vcpi = vcpi;
676 req.u.allocate_payload.pbn = pbn;
677 drm_dp_encode_sideband_req(&req, msg);
678 msg->path_msg = true;
679 return 0;
680 }
681
682 static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
683 struct drm_dp_vcpi *vcpi)
684 {
685 int ret, vcpi_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 vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1);
696 if (vcpi_ret > mgr->max_payloads) {
697 ret = -EINVAL;
698 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret);
699 goto out_unlock;
700 }
701
702 set_bit(ret, &mgr->payload_mask);
703 set_bit(vcpi_ret, &mgr->vcpi_mask);
704 vcpi->vcpi = vcpi_ret + 1;
705 mgr->proposed_vcpis[ret - 1] = vcpi;
706 out_unlock:
707 mutex_unlock(&mgr->payload_lock);
708 return ret;
709 }
710
711 static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
712 int vcpi)
713 {
714 int i;
715 if (vcpi == 0)
716 return;
717
718 mutex_lock(&mgr->payload_lock);
719 DRM_DEBUG_KMS("putting payload %d\n", vcpi);
720 clear_bit(vcpi - 1, &mgr->vcpi_mask);
721
722 for (i = 0; i < mgr->max_payloads; i++) {
723 if (mgr->proposed_vcpis[i])
724 if (mgr->proposed_vcpis[i]->vcpi == vcpi) {
725 mgr->proposed_vcpis[i] = NULL;
726 clear_bit(i + 1, &mgr->payload_mask);
727 }
728 }
729 mutex_unlock(&mgr->payload_lock);
730 }
731
732 static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
733 struct drm_dp_sideband_msg_tx *txmsg)
734 {
735 bool ret;
736
737 /*
738 * All updates to txmsg->state are protected by mgr->qlock, and the two
739 * cases we check here are terminal states. For those the barriers
740 * provided by the wake_up/wait_event pair are enough.
741 */
742 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
743 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
744 return ret;
745 }
746
747 static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
748 struct drm_dp_sideband_msg_tx *txmsg)
749 {
750 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
751 int ret;
752
753 ret = wait_event_timeout(mgr->tx_waitq,
754 check_txmsg_state(mgr, txmsg),
755 (4 * HZ));
756 mutex_lock(&mstb->mgr->qlock);
757 if (ret > 0) {
758 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
759 ret = -EIO;
760 goto out;
761 }
762 } else {
763 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
764
765 /* dump some state */
766 ret = -EIO;
767
768 /* remove from q */
769 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
770 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
771 list_del(&txmsg->next);
772 }
773
774 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
775 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
776 mstb->tx_slots[txmsg->seqno] = NULL;
777 }
778 }
779 out:
780 mutex_unlock(&mgr->qlock);
781
782 return ret;
783 }
784
785 static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
786 {
787 struct drm_dp_mst_branch *mstb;
788
789 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
790 if (!mstb)
791 return NULL;
792
793 mstb->lct = lct;
794 if (lct > 1)
795 memcpy(mstb->rad, rad, lct / 2);
796 INIT_LIST_HEAD(&mstb->ports);
797 kref_init(&mstb->kref);
798 return mstb;
799 }
800
801 static void drm_dp_destroy_mst_branch_device(struct kref *kref)
802 {
803 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
804 struct drm_dp_mst_port *port, *tmp;
805 bool wake_tx = false;
806
807 /*
808 * destroy all ports - don't need lock
809 * as there are no more references to the mst branch
810 * device at this point.
811 */
812 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
813 list_del(&port->next);
814 drm_dp_put_port(port);
815 }
816
817 /* drop any tx slots msg */
818 mutex_lock(&mstb->mgr->qlock);
819 if (mstb->tx_slots[0]) {
820 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
821 mstb->tx_slots[0] = NULL;
822 wake_tx = true;
823 }
824 if (mstb->tx_slots[1]) {
825 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
826 mstb->tx_slots[1] = NULL;
827 wake_tx = true;
828 }
829 mutex_unlock(&mstb->mgr->qlock);
830
831 if (wake_tx)
832 wake_up(&mstb->mgr->tx_waitq);
833 kfree(mstb);
834 }
835
836 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
837 {
838 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
839 }
840
841
842 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
843 {
844 struct drm_dp_mst_branch *mstb;
845
846 switch (old_pdt) {
847 case DP_PEER_DEVICE_DP_LEGACY_CONV:
848 case DP_PEER_DEVICE_SST_SINK:
849 /* remove i2c over sideband */
850 drm_dp_mst_unregister_i2c_bus(&port->aux);
851 break;
852 case DP_PEER_DEVICE_MST_BRANCHING:
853 mstb = port->mstb;
854 port->mstb = NULL;
855 drm_dp_put_mst_branch_device(mstb);
856 break;
857 }
858 }
859
860 static void drm_dp_destroy_port(struct kref *kref)
861 {
862 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
863 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
864 if (!port->input) {
865 port->vcpi.num_slots = 0;
866
867 kfree(port->cached_edid);
868
869 /* we can't destroy the connector here, as
870 we might be holding the mode_config.mutex
871 from an EDID retrieval */
872 if (port->connector) {
873 mutex_lock(&mgr->destroy_connector_lock);
874 list_add(&port->connector->destroy_list, &mgr->destroy_connector_list);
875 mutex_unlock(&mgr->destroy_connector_lock);
876 schedule_work(&mgr->destroy_connector_work);
877 }
878 drm_dp_port_teardown_pdt(port, port->pdt);
879
880 if (!port->input && port->vcpi.vcpi > 0)
881 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
882 }
883 kfree(port);
884
885 (*mgr->cbs->hotplug)(mgr);
886 }
887
888 static void drm_dp_put_port(struct drm_dp_mst_port *port)
889 {
890 kref_put(&port->kref, drm_dp_destroy_port);
891 }
892
893 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)
894 {
895 struct drm_dp_mst_port *port;
896 struct drm_dp_mst_branch *rmstb;
897 if (to_find == mstb) {
898 kref_get(&mstb->kref);
899 return mstb;
900 }
901 list_for_each_entry(port, &mstb->ports, next) {
902 if (port->mstb) {
903 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
904 if (rmstb)
905 return rmstb;
906 }
907 }
908 return NULL;
909 }
910
911 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)
912 {
913 struct drm_dp_mst_branch *rmstb = NULL;
914 mutex_lock(&mgr->lock);
915 if (mgr->mst_primary)
916 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
917 mutex_unlock(&mgr->lock);
918 return rmstb;
919 }
920
921 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)
922 {
923 struct drm_dp_mst_port *port, *mport;
924
925 list_for_each_entry(port, &mstb->ports, next) {
926 if (port == to_find) {
927 kref_get(&port->kref);
928 return port;
929 }
930 if (port->mstb) {
931 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
932 if (mport)
933 return mport;
934 }
935 }
936 return NULL;
937 }
938
939 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)
940 {
941 struct drm_dp_mst_port *rport = NULL;
942 mutex_lock(&mgr->lock);
943 if (mgr->mst_primary)
944 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
945 mutex_unlock(&mgr->lock);
946 return rport;
947 }
948
949 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
950 {
951 struct drm_dp_mst_port *port;
952
953 list_for_each_entry(port, &mstb->ports, next) {
954 if (port->port_num == port_num) {
955 kref_get(&port->kref);
956 return port;
957 }
958 }
959
960 return NULL;
961 }
962
963 /*
964 * calculate a new RAD for this MST branch device
965 * if parent has an LCT of 2 then it has 1 nibble of RAD,
966 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
967 */
968 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
969 u8 *rad)
970 {
971 int lct = port->parent->lct;
972 int shift = 4;
973 int idx = lct / 2;
974 if (lct > 1) {
975 memcpy(rad, port->parent->rad, idx);
976 shift = (lct % 2) ? 4 : 0;
977 } else
978 rad[0] = 0;
979
980 rad[idx] |= port->port_num << shift;
981 return lct + 1;
982 }
983
984 /*
985 * return sends link address for new mstb
986 */
987 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
988 {
989 int ret;
990 u8 rad[6], lct;
991 bool send_link = false;
992 switch (port->pdt) {
993 case DP_PEER_DEVICE_DP_LEGACY_CONV:
994 case DP_PEER_DEVICE_SST_SINK:
995 /* add i2c over sideband */
996 ret = drm_dp_mst_register_i2c_bus(&port->aux);
997 break;
998 case DP_PEER_DEVICE_MST_BRANCHING:
999 lct = drm_dp_calculate_rad(port, rad);
1000
1001 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
1002 port->mstb->mgr = port->mgr;
1003 port->mstb->port_parent = port;
1004
1005 send_link = true;
1006 break;
1007 }
1008 return send_link;
1009 }
1010
1011 static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
1012 struct drm_dp_mst_port *port)
1013 {
1014 int ret;
1015 if (port->dpcd_rev >= 0x12) {
1016 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
1017 if (!port->guid_valid) {
1018 ret = drm_dp_send_dpcd_write(mstb->mgr,
1019 port,
1020 DP_GUID,
1021 16, port->guid);
1022 port->guid_valid = true;
1023 }
1024 }
1025 }
1026
1027 static void build_mst_prop_path(struct drm_dp_mst_port *port,
1028 struct drm_dp_mst_branch *mstb,
1029 char *proppath,
1030 size_t proppath_size)
1031 {
1032 int i;
1033 char temp[8];
1034 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
1035 for (i = 0; i < (mstb->lct - 1); i++) {
1036 int shift = (i % 2) ? 0 : 4;
1037 int port_num = mstb->rad[i / 2] >> shift;
1038 snprintf(temp, sizeof(temp), "-%d", port_num);
1039 strlcat(proppath, temp, proppath_size);
1040 }
1041 snprintf(temp, sizeof(temp), "-%d", port->port_num);
1042 strlcat(proppath, temp, proppath_size);
1043 }
1044
1045 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1046 struct device *dev,
1047 struct drm_dp_link_addr_reply_port *port_msg)
1048 {
1049 struct drm_dp_mst_port *port;
1050 bool ret;
1051 bool created = false;
1052 int old_pdt = 0;
1053 int old_ddps = 0;
1054 port = drm_dp_get_port(mstb, port_msg->port_number);
1055 if (!port) {
1056 port = kzalloc(sizeof(*port), GFP_KERNEL);
1057 if (!port)
1058 return;
1059 kref_init(&port->kref);
1060 port->parent = mstb;
1061 port->port_num = port_msg->port_number;
1062 port->mgr = mstb->mgr;
1063 port->aux.name = "DPMST";
1064 port->aux.dev = dev;
1065 created = true;
1066 } else {
1067 old_pdt = port->pdt;
1068 old_ddps = port->ddps;
1069 }
1070
1071 port->pdt = port_msg->peer_device_type;
1072 port->input = port_msg->input_port;
1073 port->mcs = port_msg->mcs;
1074 port->ddps = port_msg->ddps;
1075 port->ldps = port_msg->legacy_device_plug_status;
1076 port->dpcd_rev = port_msg->dpcd_revision;
1077 port->num_sdp_streams = port_msg->num_sdp_streams;
1078 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1079 memcpy(port->guid, port_msg->peer_guid, 16);
1080
1081 /* manage mstb port lists with mgr lock - take a reference
1082 for this list */
1083 if (created) {
1084 mutex_lock(&mstb->mgr->lock);
1085 kref_get(&port->kref);
1086 list_add(&port->next, &mstb->ports);
1087 mutex_unlock(&mstb->mgr->lock);
1088 }
1089
1090 if (old_ddps != port->ddps) {
1091 if (port->ddps) {
1092 drm_dp_check_port_guid(mstb, port);
1093 if (!port->input)
1094 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1095 } else {
1096 port->guid_valid = false;
1097 port->available_pbn = 0;
1098 }
1099 }
1100
1101 if (old_pdt != port->pdt && !port->input) {
1102 drm_dp_port_teardown_pdt(port, old_pdt);
1103
1104 ret = drm_dp_port_setup_pdt(port);
1105 if (ret == true) {
1106 drm_dp_send_link_address(mstb->mgr, port->mstb);
1107 port->mstb->link_address_sent = true;
1108 }
1109 }
1110
1111 if (created && !port->input) {
1112 char proppath[255];
1113 build_mst_prop_path(port, mstb, proppath, sizeof(proppath));
1114 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1115
1116 if (port->port_num >= 8) {
1117 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
1118 }
1119 }
1120
1121 /* put reference to this port */
1122 drm_dp_put_port(port);
1123 }
1124
1125 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1126 struct drm_dp_connection_status_notify *conn_stat)
1127 {
1128 struct drm_dp_mst_port *port;
1129 int old_pdt;
1130 int old_ddps;
1131 bool dowork = false;
1132 port = drm_dp_get_port(mstb, conn_stat->port_number);
1133 if (!port)
1134 return;
1135
1136 old_ddps = port->ddps;
1137 old_pdt = port->pdt;
1138 port->pdt = conn_stat->peer_device_type;
1139 port->mcs = conn_stat->message_capability_status;
1140 port->ldps = conn_stat->legacy_device_plug_status;
1141 port->ddps = conn_stat->displayport_device_plug_status;
1142
1143 if (old_ddps != port->ddps) {
1144 if (port->ddps) {
1145 drm_dp_check_port_guid(mstb, port);
1146 dowork = true;
1147 } else {
1148 port->guid_valid = false;
1149 port->available_pbn = 0;
1150 }
1151 }
1152 if (old_pdt != port->pdt && !port->input) {
1153 drm_dp_port_teardown_pdt(port, old_pdt);
1154
1155 if (drm_dp_port_setup_pdt(port))
1156 dowork = true;
1157 }
1158
1159 drm_dp_put_port(port);
1160 if (dowork)
1161 queue_work(system_long_wq, &mstb->mgr->work);
1162
1163 }
1164
1165 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1166 u8 lct, u8 *rad)
1167 {
1168 struct drm_dp_mst_branch *mstb;
1169 struct drm_dp_mst_port *port;
1170 int i;
1171 /* find the port by iterating down */
1172
1173 mutex_lock(&mgr->lock);
1174 mstb = mgr->mst_primary;
1175
1176 for (i = 0; i < lct - 1; i++) {
1177 int shift = (i % 2) ? 0 : 4;
1178 int port_num = rad[i / 2] >> shift;
1179
1180 list_for_each_entry(port, &mstb->ports, next) {
1181 if (port->port_num == port_num) {
1182 mstb = port->mstb;
1183 if (!mstb) {
1184 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1185 goto out;
1186 }
1187
1188 break;
1189 }
1190 }
1191 }
1192 kref_get(&mstb->kref);
1193 out:
1194 mutex_unlock(&mgr->lock);
1195 return mstb;
1196 }
1197
1198 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1199 struct drm_dp_mst_branch *mstb)
1200 {
1201 struct drm_dp_mst_port *port;
1202 struct drm_dp_mst_branch *mstb_child;
1203 if (!mstb->link_address_sent) {
1204 drm_dp_send_link_address(mgr, mstb);
1205 mstb->link_address_sent = true;
1206 }
1207 list_for_each_entry(port, &mstb->ports, next) {
1208 if (port->input)
1209 continue;
1210
1211 if (!port->ddps)
1212 continue;
1213
1214 if (!port->available_pbn)
1215 drm_dp_send_enum_path_resources(mgr, mstb, port);
1216
1217 if (port->mstb) {
1218 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
1219 if (mstb_child) {
1220 drm_dp_check_and_send_link_address(mgr, mstb_child);
1221 drm_dp_put_mst_branch_device(mstb_child);
1222 }
1223 }
1224 }
1225 }
1226
1227 static void drm_dp_mst_link_probe_work(struct work_struct *work)
1228 {
1229 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1230 struct drm_dp_mst_branch *mstb;
1231
1232 mutex_lock(&mgr->lock);
1233 mstb = mgr->mst_primary;
1234 if (mstb) {
1235 kref_get(&mstb->kref);
1236 }
1237 mutex_unlock(&mgr->lock);
1238 if (mstb) {
1239 drm_dp_check_and_send_link_address(mgr, mstb);
1240 drm_dp_put_mst_branch_device(mstb);
1241 }
1242 }
1243
1244 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1245 u8 *guid)
1246 {
1247 static u8 zero_guid[16];
1248
1249 if (!memcmp(guid, zero_guid, 16)) {
1250 u64 salt = get_jiffies_64();
1251 memcpy(&guid[0], &salt, sizeof(u64));
1252 memcpy(&guid[8], &salt, sizeof(u64));
1253 return false;
1254 }
1255 return true;
1256 }
1257
1258 #if 0
1259 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1260 {
1261 struct drm_dp_sideband_msg_req_body req;
1262
1263 req.req_type = DP_REMOTE_DPCD_READ;
1264 req.u.dpcd_read.port_number = port_num;
1265 req.u.dpcd_read.dpcd_address = offset;
1266 req.u.dpcd_read.num_bytes = num_bytes;
1267 drm_dp_encode_sideband_req(&req, msg);
1268
1269 return 0;
1270 }
1271 #endif
1272
1273 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1274 bool up, u8 *msg, int len)
1275 {
1276 int ret;
1277 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1278 int tosend, total, offset;
1279 int retries = 0;
1280
1281 retry:
1282 total = len;
1283 offset = 0;
1284 do {
1285 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1286
1287 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1288 &msg[offset],
1289 tosend);
1290 if (ret != tosend) {
1291 if (ret == -EIO && retries < 5) {
1292 retries++;
1293 goto retry;
1294 }
1295 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1296
1297 return -EIO;
1298 }
1299 offset += tosend;
1300 total -= tosend;
1301 } while (total > 0);
1302 return 0;
1303 }
1304
1305 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1306 struct drm_dp_sideband_msg_tx *txmsg)
1307 {
1308 struct drm_dp_mst_branch *mstb = txmsg->dst;
1309
1310 /* both msg slots are full */
1311 if (txmsg->seqno == -1) {
1312 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1313 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1314 return -EAGAIN;
1315 }
1316 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1317 txmsg->seqno = mstb->last_seqno;
1318 mstb->last_seqno ^= 1;
1319 } else if (mstb->tx_slots[0] == NULL)
1320 txmsg->seqno = 0;
1321 else
1322 txmsg->seqno = 1;
1323 mstb->tx_slots[txmsg->seqno] = txmsg;
1324 }
1325 hdr->broadcast = 0;
1326 hdr->path_msg = txmsg->path_msg;
1327 hdr->lct = mstb->lct;
1328 hdr->lcr = mstb->lct - 1;
1329 if (mstb->lct > 1)
1330 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1331 hdr->seqno = txmsg->seqno;
1332 return 0;
1333 }
1334 /*
1335 * process a single block of the next message in the sideband queue
1336 */
1337 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1338 struct drm_dp_sideband_msg_tx *txmsg,
1339 bool up)
1340 {
1341 u8 chunk[48];
1342 struct drm_dp_sideband_msg_hdr hdr;
1343 int len, space, idx, tosend;
1344 int ret;
1345
1346 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1347
1348 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1349 txmsg->seqno = -1;
1350 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1351 }
1352
1353 /* make hdr from dst mst - for replies use seqno
1354 otherwise assign one */
1355 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1356 if (ret < 0)
1357 return ret;
1358
1359 /* amount left to send in this message */
1360 len = txmsg->cur_len - txmsg->cur_offset;
1361
1362 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1363 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1364
1365 tosend = min(len, space);
1366 if (len == txmsg->cur_len)
1367 hdr.somt = 1;
1368 if (space >= len)
1369 hdr.eomt = 1;
1370
1371
1372 hdr.msg_len = tosend + 1;
1373 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1374 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1375 /* add crc at end */
1376 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1377 idx += tosend + 1;
1378
1379 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1380 if (ret) {
1381 DRM_DEBUG_KMS("sideband msg failed to send\n");
1382 return ret;
1383 }
1384
1385 txmsg->cur_offset += tosend;
1386 if (txmsg->cur_offset == txmsg->cur_len) {
1387 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1388 return 1;
1389 }
1390 return 0;
1391 }
1392
1393 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1394 {
1395 struct drm_dp_sideband_msg_tx *txmsg;
1396 int ret;
1397
1398 WARN_ON(!mutex_is_locked(&mgr->qlock));
1399
1400 /* construct a chunk from the first msg in the tx_msg queue */
1401 if (list_empty(&mgr->tx_msg_downq)) {
1402 mgr->tx_down_in_progress = false;
1403 return;
1404 }
1405 mgr->tx_down_in_progress = true;
1406
1407 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1408 ret = process_single_tx_qlock(mgr, txmsg, false);
1409 if (ret == 1) {
1410 /* txmsg is sent it should be in the slots now */
1411 list_del(&txmsg->next);
1412 } else if (ret) {
1413 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1414 list_del(&txmsg->next);
1415 if (txmsg->seqno != -1)
1416 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1417 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1418 wake_up(&mgr->tx_waitq);
1419 }
1420 if (list_empty(&mgr->tx_msg_downq)) {
1421 mgr->tx_down_in_progress = false;
1422 return;
1423 }
1424 }
1425
1426 /* called holding qlock */
1427 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1428 {
1429 struct drm_dp_sideband_msg_tx *txmsg;
1430 int ret;
1431
1432 /* construct a chunk from the first msg in the tx_msg queue */
1433 if (list_empty(&mgr->tx_msg_upq)) {
1434 mgr->tx_up_in_progress = false;
1435 return;
1436 }
1437
1438 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1439 ret = process_single_tx_qlock(mgr, txmsg, true);
1440 if (ret == 1) {
1441 /* up txmsgs aren't put in slots - so free after we send it */
1442 list_del(&txmsg->next);
1443 kfree(txmsg);
1444 } else if (ret)
1445 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1446 mgr->tx_up_in_progress = true;
1447 }
1448
1449 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1450 struct drm_dp_sideband_msg_tx *txmsg)
1451 {
1452 mutex_lock(&mgr->qlock);
1453 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1454 if (!mgr->tx_down_in_progress)
1455 process_single_down_tx_qlock(mgr);
1456 mutex_unlock(&mgr->qlock);
1457 }
1458
1459 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1460 struct drm_dp_mst_branch *mstb)
1461 {
1462 int len;
1463 struct drm_dp_sideband_msg_tx *txmsg;
1464 int ret;
1465
1466 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1467 if (!txmsg)
1468 return -ENOMEM;
1469
1470 txmsg->dst = mstb;
1471 len = build_link_address(txmsg);
1472
1473 drm_dp_queue_down_tx(mgr, txmsg);
1474
1475 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1476 if (ret > 0) {
1477 int i;
1478
1479 if (txmsg->reply.reply_type == 1)
1480 DRM_DEBUG_KMS("link address nak received\n");
1481 else {
1482 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1483 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1484 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,
1485 txmsg->reply.u.link_addr.ports[i].input_port,
1486 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1487 txmsg->reply.u.link_addr.ports[i].port_number,
1488 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1489 txmsg->reply.u.link_addr.ports[i].mcs,
1490 txmsg->reply.u.link_addr.ports[i].ddps,
1491 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1492 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1493 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1494 }
1495 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1496 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1497 }
1498 (*mgr->cbs->hotplug)(mgr);
1499 }
1500 } else
1501 DRM_DEBUG_KMS("link address failed %d\n", ret);
1502
1503 kfree(txmsg);
1504 return 0;
1505 }
1506
1507 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1508 struct drm_dp_mst_branch *mstb,
1509 struct drm_dp_mst_port *port)
1510 {
1511 int len;
1512 struct drm_dp_sideband_msg_tx *txmsg;
1513 int ret;
1514
1515 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1516 if (!txmsg)
1517 return -ENOMEM;
1518
1519 txmsg->dst = mstb;
1520 len = build_enum_path_resources(txmsg, port->port_num);
1521
1522 drm_dp_queue_down_tx(mgr, txmsg);
1523
1524 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1525 if (ret > 0) {
1526 if (txmsg->reply.reply_type == 1)
1527 DRM_DEBUG_KMS("enum path resources nak received\n");
1528 else {
1529 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1530 DRM_ERROR("got incorrect port in response\n");
1531 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,
1532 txmsg->reply.u.path_resources.avail_payload_bw_number);
1533 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1534 }
1535 }
1536
1537 kfree(txmsg);
1538 return 0;
1539 }
1540
1541 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1542 struct drm_dp_mst_port *port,
1543 int id,
1544 int pbn)
1545 {
1546 struct drm_dp_sideband_msg_tx *txmsg;
1547 struct drm_dp_mst_branch *mstb;
1548 int len, ret;
1549
1550 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1551 if (!mstb)
1552 return -EINVAL;
1553
1554 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1555 if (!txmsg) {
1556 ret = -ENOMEM;
1557 goto fail_put;
1558 }
1559
1560 txmsg->dst = mstb;
1561 len = build_allocate_payload(txmsg, port->port_num,
1562 id,
1563 pbn);
1564
1565 drm_dp_queue_down_tx(mgr, txmsg);
1566
1567 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1568 if (ret > 0) {
1569 if (txmsg->reply.reply_type == 1) {
1570 ret = -EINVAL;
1571 } else
1572 ret = 0;
1573 }
1574 kfree(txmsg);
1575 fail_put:
1576 drm_dp_put_mst_branch_device(mstb);
1577 return ret;
1578 }
1579
1580 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1581 int id,
1582 struct drm_dp_payload *payload)
1583 {
1584 int ret;
1585
1586 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1587 if (ret < 0) {
1588 payload->payload_state = 0;
1589 return ret;
1590 }
1591 payload->payload_state = DP_PAYLOAD_LOCAL;
1592 return 0;
1593 }
1594
1595 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1596 struct drm_dp_mst_port *port,
1597 int id,
1598 struct drm_dp_payload *payload)
1599 {
1600 int ret;
1601 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1602 if (ret < 0)
1603 return ret;
1604 payload->payload_state = DP_PAYLOAD_REMOTE;
1605 return ret;
1606 }
1607
1608 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1609 struct drm_dp_mst_port *port,
1610 int id,
1611 struct drm_dp_payload *payload)
1612 {
1613 DRM_DEBUG_KMS("\n");
1614 /* its okay for these to fail */
1615 if (port) {
1616 drm_dp_payload_send_msg(mgr, port, id, 0);
1617 }
1618
1619 drm_dp_dpcd_write_payload(mgr, id, payload);
1620 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
1621 return 0;
1622 }
1623
1624 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1625 int id,
1626 struct drm_dp_payload *payload)
1627 {
1628 payload->payload_state = 0;
1629 return 0;
1630 }
1631
1632 /**
1633 * drm_dp_update_payload_part1() - Execute payload update part 1
1634 * @mgr: manager to use.
1635 *
1636 * This iterates over all proposed virtual channels, and tries to
1637 * allocate space in the link for them. For 0->slots transitions,
1638 * this step just writes the VCPI to the MST device. For slots->0
1639 * transitions, this writes the updated VCPIs and removes the
1640 * remote VC payloads.
1641 *
1642 * after calling this the driver should generate ACT and payload
1643 * packets.
1644 */
1645 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1646 {
1647 int i, j;
1648 int cur_slots = 1;
1649 struct drm_dp_payload req_payload;
1650 struct drm_dp_mst_port *port;
1651
1652 mutex_lock(&mgr->payload_lock);
1653 for (i = 0; i < mgr->max_payloads; i++) {
1654 /* solve the current payloads - compare to the hw ones
1655 - update the hw view */
1656 req_payload.start_slot = cur_slots;
1657 if (mgr->proposed_vcpis[i]) {
1658 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1659 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1660 } else {
1661 port = NULL;
1662 req_payload.num_slots = 0;
1663 }
1664
1665 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1666 mgr->payloads[i].start_slot = req_payload.start_slot;
1667 }
1668 /* work out what is required to happen with this payload */
1669 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
1670
1671 /* need to push an update for this payload */
1672 if (req_payload.num_slots) {
1673 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
1674 mgr->payloads[i].num_slots = req_payload.num_slots;
1675 } else if (mgr->payloads[i].num_slots) {
1676 mgr->payloads[i].num_slots = 0;
1677 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
1678 req_payload.payload_state = mgr->payloads[i].payload_state;
1679 mgr->payloads[i].start_slot = 0;
1680 }
1681 mgr->payloads[i].payload_state = req_payload.payload_state;
1682 }
1683 cur_slots += req_payload.num_slots;
1684 }
1685
1686 for (i = 0; i < mgr->max_payloads; i++) {
1687 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1688 DRM_DEBUG_KMS("removing payload %d\n", i);
1689 for (j = i; j < mgr->max_payloads - 1; j++) {
1690 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1691 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1692 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1693 set_bit(j + 1, &mgr->payload_mask);
1694 } else {
1695 clear_bit(j + 1, &mgr->payload_mask);
1696 }
1697 }
1698 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1699 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1700 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1701
1702 }
1703 }
1704 mutex_unlock(&mgr->payload_lock);
1705
1706 return 0;
1707 }
1708 EXPORT_SYMBOL(drm_dp_update_payload_part1);
1709
1710 /**
1711 * drm_dp_update_payload_part2() - Execute payload update part 2
1712 * @mgr: manager to use.
1713 *
1714 * This iterates over all proposed virtual channels, and tries to
1715 * allocate space in the link for them. For 0->slots transitions,
1716 * this step writes the remote VC payload commands. For slots->0
1717 * this just resets some internal state.
1718 */
1719 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1720 {
1721 struct drm_dp_mst_port *port;
1722 int i;
1723 int ret = 0;
1724 mutex_lock(&mgr->payload_lock);
1725 for (i = 0; i < mgr->max_payloads; i++) {
1726
1727 if (!mgr->proposed_vcpis[i])
1728 continue;
1729
1730 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1731
1732 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1733 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1734 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1735 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1736 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1737 }
1738 if (ret) {
1739 mutex_unlock(&mgr->payload_lock);
1740 return ret;
1741 }
1742 }
1743 mutex_unlock(&mgr->payload_lock);
1744 return 0;
1745 }
1746 EXPORT_SYMBOL(drm_dp_update_payload_part2);
1747
1748 #if 0 /* unused as of yet */
1749 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1750 struct drm_dp_mst_port *port,
1751 int offset, int size)
1752 {
1753 int len;
1754 struct drm_dp_sideband_msg_tx *txmsg;
1755
1756 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1757 if (!txmsg)
1758 return -ENOMEM;
1759
1760 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1761 txmsg->dst = port->parent;
1762
1763 drm_dp_queue_down_tx(mgr, txmsg);
1764
1765 return 0;
1766 }
1767 #endif
1768
1769 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1770 struct drm_dp_mst_port *port,
1771 int offset, int size, u8 *bytes)
1772 {
1773 int len;
1774 int ret;
1775 struct drm_dp_sideband_msg_tx *txmsg;
1776 struct drm_dp_mst_branch *mstb;
1777
1778 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1779 if (!mstb)
1780 return -EINVAL;
1781
1782 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1783 if (!txmsg) {
1784 ret = -ENOMEM;
1785 goto fail_put;
1786 }
1787
1788 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1789 txmsg->dst = mstb;
1790
1791 drm_dp_queue_down_tx(mgr, txmsg);
1792
1793 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1794 if (ret > 0) {
1795 if (txmsg->reply.reply_type == 1) {
1796 ret = -EINVAL;
1797 } else
1798 ret = 0;
1799 }
1800 kfree(txmsg);
1801 fail_put:
1802 drm_dp_put_mst_branch_device(mstb);
1803 return ret;
1804 }
1805
1806 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1807 {
1808 struct drm_dp_sideband_msg_reply_body reply;
1809
1810 reply.reply_type = 1;
1811 reply.req_type = req_type;
1812 drm_dp_encode_sideband_reply(&reply, msg);
1813 return 0;
1814 }
1815
1816 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1817 struct drm_dp_mst_branch *mstb,
1818 int req_type, int seqno, bool broadcast)
1819 {
1820 struct drm_dp_sideband_msg_tx *txmsg;
1821
1822 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1823 if (!txmsg)
1824 return -ENOMEM;
1825
1826 txmsg->dst = mstb;
1827 txmsg->seqno = seqno;
1828 drm_dp_encode_up_ack_reply(txmsg, req_type);
1829
1830 mutex_lock(&mgr->qlock);
1831 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1832 if (!mgr->tx_up_in_progress) {
1833 process_single_up_tx_qlock(mgr);
1834 }
1835 mutex_unlock(&mgr->qlock);
1836 return 0;
1837 }
1838
1839 static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
1840 int dp_link_count,
1841 int *out)
1842 {
1843 switch (dp_link_bw) {
1844 default:
1845 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
1846 dp_link_bw, dp_link_count);
1847 return false;
1848
1849 case DP_LINK_BW_1_62:
1850 *out = 3 * dp_link_count;
1851 break;
1852 case DP_LINK_BW_2_7:
1853 *out = 5 * dp_link_count;
1854 break;
1855 case DP_LINK_BW_5_4:
1856 *out = 10 * dp_link_count;
1857 break;
1858 }
1859 return true;
1860 }
1861
1862 /**
1863 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1864 * @mgr: manager to set state for
1865 * @mst_state: true to enable MST on this connector - false to disable.
1866 *
1867 * This is called by the driver when it detects an MST capable device plugged
1868 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1869 */
1870 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1871 {
1872 int ret = 0;
1873 struct drm_dp_mst_branch *mstb = NULL;
1874
1875 mutex_lock(&mgr->lock);
1876 if (mst_state == mgr->mst_state)
1877 goto out_unlock;
1878
1879 mgr->mst_state = mst_state;
1880 /* set the device into MST mode */
1881 if (mst_state) {
1882 WARN_ON(mgr->mst_primary);
1883
1884 /* get dpcd info */
1885 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1886 if (ret != DP_RECEIVER_CAP_SIZE) {
1887 DRM_DEBUG_KMS("failed to read DPCD\n");
1888 goto out_unlock;
1889 }
1890
1891 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
1892 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
1893 &mgr->pbn_div)) {
1894 ret = -EINVAL;
1895 goto out_unlock;
1896 }
1897
1898 mgr->total_pbn = 2560;
1899 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1900 mgr->avail_slots = mgr->total_slots;
1901
1902 /* add initial branch device at LCT 1 */
1903 mstb = drm_dp_add_mst_branch_device(1, NULL);
1904 if (mstb == NULL) {
1905 ret = -ENOMEM;
1906 goto out_unlock;
1907 }
1908 mstb->mgr = mgr;
1909
1910 /* give this the main reference */
1911 mgr->mst_primary = mstb;
1912 kref_get(&mgr->mst_primary->kref);
1913
1914 {
1915 struct drm_dp_payload reset_pay;
1916 reset_pay.start_slot = 0;
1917 reset_pay.num_slots = 0x3f;
1918 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1919 }
1920
1921 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1922 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1923 if (ret < 0) {
1924 goto out_unlock;
1925 }
1926
1927
1928 /* sort out guid */
1929 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1930 if (ret != 16) {
1931 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1932 goto out_unlock;
1933 }
1934
1935 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1936 if (!mgr->guid_valid) {
1937 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1938 mgr->guid_valid = true;
1939 }
1940
1941 queue_work(system_long_wq, &mgr->work);
1942
1943 ret = 0;
1944 } else {
1945 /* disable MST on the device */
1946 mstb = mgr->mst_primary;
1947 mgr->mst_primary = NULL;
1948 /* this can fail if the device is gone */
1949 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1950 ret = 0;
1951 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1952 mgr->payload_mask = 0;
1953 set_bit(0, &mgr->payload_mask);
1954 mgr->vcpi_mask = 0;
1955 }
1956
1957 out_unlock:
1958 mutex_unlock(&mgr->lock);
1959 if (mstb)
1960 drm_dp_put_mst_branch_device(mstb);
1961 return ret;
1962
1963 }
1964 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1965
1966 /**
1967 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1968 * @mgr: manager to suspend
1969 *
1970 * This function tells the MST device that we can't handle UP messages
1971 * anymore. This should stop it from sending any since we are suspended.
1972 */
1973 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1974 {
1975 mutex_lock(&mgr->lock);
1976 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1977 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1978 mutex_unlock(&mgr->lock);
1979 flush_work(&mgr->work);
1980 flush_work(&mgr->destroy_connector_work);
1981 }
1982 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1983
1984 /**
1985 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1986 * @mgr: manager to resume
1987 *
1988 * This will fetch DPCD and see if the device is still there,
1989 * if it is, it will rewrite the MSTM control bits, and return.
1990 *
1991 * if the device fails this returns -1, and the driver should do
1992 * a full MST reprobe, in case we were undocked.
1993 */
1994 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1995 {
1996 int ret = 0;
1997
1998 mutex_lock(&mgr->lock);
1999
2000 if (mgr->mst_primary) {
2001 int sret;
2002 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
2003 if (sret != DP_RECEIVER_CAP_SIZE) {
2004 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
2005 ret = -1;
2006 goto out_unlock;
2007 }
2008
2009 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
2010 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
2011 if (ret < 0) {
2012 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
2013 ret = -1;
2014 goto out_unlock;
2015 }
2016 ret = 0;
2017 } else
2018 ret = -1;
2019
2020 out_unlock:
2021 mutex_unlock(&mgr->lock);
2022 return ret;
2023 }
2024 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
2025
2026 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
2027 {
2028 int len;
2029 u8 replyblock[32];
2030 int replylen, origlen, curreply;
2031 int ret;
2032 struct drm_dp_sideband_msg_rx *msg;
2033 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
2034 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
2035
2036 len = min(mgr->max_dpcd_transaction_bytes, 16);
2037 ret = drm_dp_dpcd_read(mgr->aux, basereg,
2038 replyblock, len);
2039 if (ret != len) {
2040 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
2041 return;
2042 }
2043 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
2044 if (!ret) {
2045 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
2046 return;
2047 }
2048 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
2049
2050 origlen = replylen;
2051 replylen -= len;
2052 curreply = len;
2053 while (replylen > 0) {
2054 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2055 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2056 replyblock, len);
2057 if (ret != len) {
2058 DRM_DEBUG_KMS("failed to read a chunk\n");
2059 }
2060 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2061 if (ret == false)
2062 DRM_DEBUG_KMS("failed to build sideband msg\n");
2063 curreply += len;
2064 replylen -= len;
2065 }
2066 }
2067
2068 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2069 {
2070 int ret = 0;
2071
2072 drm_dp_get_one_sb_msg(mgr, false);
2073
2074 if (mgr->down_rep_recv.have_eomt) {
2075 struct drm_dp_sideband_msg_tx *txmsg;
2076 struct drm_dp_mst_branch *mstb;
2077 int slot = -1;
2078 mstb = drm_dp_get_mst_branch_device(mgr,
2079 mgr->down_rep_recv.initial_hdr.lct,
2080 mgr->down_rep_recv.initial_hdr.rad);
2081
2082 if (!mstb) {
2083 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2084 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2085 return 0;
2086 }
2087
2088 /* find the message */
2089 slot = mgr->down_rep_recv.initial_hdr.seqno;
2090 mutex_lock(&mgr->qlock);
2091 txmsg = mstb->tx_slots[slot];
2092 /* remove from slots */
2093 mutex_unlock(&mgr->qlock);
2094
2095 if (!txmsg) {
2096 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2097 mstb,
2098 mgr->down_rep_recv.initial_hdr.seqno,
2099 mgr->down_rep_recv.initial_hdr.lct,
2100 mgr->down_rep_recv.initial_hdr.rad[0],
2101 mgr->down_rep_recv.msg[0]);
2102 drm_dp_put_mst_branch_device(mstb);
2103 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2104 return 0;
2105 }
2106
2107 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2108 if (txmsg->reply.reply_type == 1) {
2109 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);
2110 }
2111
2112 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2113 drm_dp_put_mst_branch_device(mstb);
2114
2115 mutex_lock(&mgr->qlock);
2116 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2117 mstb->tx_slots[slot] = NULL;
2118 mutex_unlock(&mgr->qlock);
2119
2120 wake_up(&mgr->tx_waitq);
2121 }
2122 return ret;
2123 }
2124
2125 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2126 {
2127 int ret = 0;
2128 drm_dp_get_one_sb_msg(mgr, true);
2129
2130 if (mgr->up_req_recv.have_eomt) {
2131 struct drm_dp_sideband_msg_req_body msg;
2132 struct drm_dp_mst_branch *mstb;
2133 bool seqno;
2134 mstb = drm_dp_get_mst_branch_device(mgr,
2135 mgr->up_req_recv.initial_hdr.lct,
2136 mgr->up_req_recv.initial_hdr.rad);
2137 if (!mstb) {
2138 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2139 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2140 return 0;
2141 }
2142
2143 seqno = mgr->up_req_recv.initial_hdr.seqno;
2144 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2145
2146 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2147 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2148 drm_dp_update_port(mstb, &msg.u.conn_stat);
2149 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);
2150 (*mgr->cbs->hotplug)(mgr);
2151
2152 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2153 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2154 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2155 }
2156
2157 drm_dp_put_mst_branch_device(mstb);
2158 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2159 }
2160 return ret;
2161 }
2162
2163 /**
2164 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2165 * @mgr: manager to notify irq for.
2166 * @esi: 4 bytes from SINK_COUNT_ESI
2167 * @handled: whether the hpd interrupt was consumed or not
2168 *
2169 * This should be called from the driver when it detects a short IRQ,
2170 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2171 * topology manager will process the sideband messages received as a result
2172 * of this.
2173 */
2174 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2175 {
2176 int ret = 0;
2177 int sc;
2178 *handled = false;
2179 sc = esi[0] & 0x3f;
2180
2181 if (sc != mgr->sink_count) {
2182 mgr->sink_count = sc;
2183 *handled = true;
2184 }
2185
2186 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2187 ret = drm_dp_mst_handle_down_rep(mgr);
2188 *handled = true;
2189 }
2190
2191 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2192 ret |= drm_dp_mst_handle_up_req(mgr);
2193 *handled = true;
2194 }
2195
2196 drm_dp_mst_kick_tx(mgr);
2197 return ret;
2198 }
2199 EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2200
2201 /**
2202 * drm_dp_mst_detect_port() - get connection status for an MST port
2203 * @mgr: manager for this port
2204 * @port: unverified pointer to a port
2205 *
2206 * This returns the current connection state for a port. It validates the
2207 * port pointer still exists so the caller doesn't require a reference
2208 */
2209 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
2210 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2211 {
2212 enum drm_connector_status status = connector_status_disconnected;
2213
2214 /* we need to search for the port in the mgr in case its gone */
2215 port = drm_dp_get_validated_port_ref(mgr, port);
2216 if (!port)
2217 return connector_status_disconnected;
2218
2219 if (!port->ddps)
2220 goto out;
2221
2222 switch (port->pdt) {
2223 case DP_PEER_DEVICE_NONE:
2224 case DP_PEER_DEVICE_MST_BRANCHING:
2225 break;
2226
2227 case DP_PEER_DEVICE_SST_SINK:
2228 status = connector_status_connected;
2229 /* for logical ports - cache the EDID */
2230 if (port->port_num >= 8 && !port->cached_edid) {
2231 port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
2232 }
2233 break;
2234 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2235 if (port->ldps)
2236 status = connector_status_connected;
2237 break;
2238 }
2239 out:
2240 drm_dp_put_port(port);
2241 return status;
2242 }
2243 EXPORT_SYMBOL(drm_dp_mst_detect_port);
2244
2245 /**
2246 * drm_dp_mst_get_edid() - get EDID for an MST port
2247 * @connector: toplevel connector to get EDID for
2248 * @mgr: manager for this port
2249 * @port: unverified pointer to a port.
2250 *
2251 * This returns an EDID for the port connected to a connector,
2252 * It validates the pointer still exists so the caller doesn't require a
2253 * reference.
2254 */
2255 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2256 {
2257 struct edid *edid = NULL;
2258
2259 /* we need to search for the port in the mgr in case its gone */
2260 port = drm_dp_get_validated_port_ref(mgr, port);
2261 if (!port)
2262 return NULL;
2263
2264 if (port->cached_edid)
2265 edid = drm_edid_duplicate(port->cached_edid);
2266 else
2267 edid = drm_get_edid(connector, &port->aux.ddc);
2268
2269 drm_mode_connector_set_tile_property(connector);
2270 drm_dp_put_port(port);
2271 return edid;
2272 }
2273 EXPORT_SYMBOL(drm_dp_mst_get_edid);
2274
2275 /**
2276 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2277 * @mgr: manager to use
2278 * @pbn: payload bandwidth to convert into slots.
2279 */
2280 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2281 int pbn)
2282 {
2283 int num_slots;
2284
2285 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2286
2287 if (num_slots > mgr->avail_slots)
2288 return -ENOSPC;
2289 return num_slots;
2290 }
2291 EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2292
2293 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2294 struct drm_dp_vcpi *vcpi, int pbn)
2295 {
2296 int num_slots;
2297 int ret;
2298
2299 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2300
2301 if (num_slots > mgr->avail_slots)
2302 return -ENOSPC;
2303
2304 vcpi->pbn = pbn;
2305 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2306 vcpi->num_slots = num_slots;
2307
2308 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2309 if (ret < 0)
2310 return ret;
2311 return 0;
2312 }
2313
2314 /**
2315 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2316 * @mgr: manager for this port
2317 * @port: port to allocate a virtual channel for.
2318 * @pbn: payload bandwidth number to request
2319 * @slots: returned number of slots for this PBN.
2320 */
2321 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2322 {
2323 int ret;
2324
2325 port = drm_dp_get_validated_port_ref(mgr, port);
2326 if (!port)
2327 return false;
2328
2329 if (port->vcpi.vcpi > 0) {
2330 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2331 if (pbn == port->vcpi.pbn) {
2332 *slots = port->vcpi.num_slots;
2333 return true;
2334 }
2335 }
2336
2337 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2338 if (ret) {
2339 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2340 goto out;
2341 }
2342 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2343 *slots = port->vcpi.num_slots;
2344
2345 drm_dp_put_port(port);
2346 return true;
2347 out:
2348 return false;
2349 }
2350 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2351
2352 int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2353 {
2354 int slots = 0;
2355 port = drm_dp_get_validated_port_ref(mgr, port);
2356 if (!port)
2357 return slots;
2358
2359 slots = port->vcpi.num_slots;
2360 drm_dp_put_port(port);
2361 return slots;
2362 }
2363 EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots);
2364
2365 /**
2366 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2367 * @mgr: manager for this port
2368 * @port: unverified pointer to a port.
2369 *
2370 * This just resets the number of slots for the ports VCPI for later programming.
2371 */
2372 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2373 {
2374 port = drm_dp_get_validated_port_ref(mgr, port);
2375 if (!port)
2376 return;
2377 port->vcpi.num_slots = 0;
2378 drm_dp_put_port(port);
2379 }
2380 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2381
2382 /**
2383 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2384 * @mgr: manager for this port
2385 * @port: unverified port to deallocate vcpi for
2386 */
2387 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2388 {
2389 port = drm_dp_get_validated_port_ref(mgr, port);
2390 if (!port)
2391 return;
2392
2393 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2394 port->vcpi.num_slots = 0;
2395 port->vcpi.pbn = 0;
2396 port->vcpi.aligned_pbn = 0;
2397 port->vcpi.vcpi = 0;
2398 drm_dp_put_port(port);
2399 }
2400 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2401
2402 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2403 int id, struct drm_dp_payload *payload)
2404 {
2405 u8 payload_alloc[3], status;
2406 int ret;
2407 int retries = 0;
2408
2409 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2410 DP_PAYLOAD_TABLE_UPDATED);
2411
2412 payload_alloc[0] = id;
2413 payload_alloc[1] = payload->start_slot;
2414 payload_alloc[2] = payload->num_slots;
2415
2416 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2417 if (ret != 3) {
2418 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2419 goto fail;
2420 }
2421
2422 retry:
2423 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2424 if (ret < 0) {
2425 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2426 goto fail;
2427 }
2428
2429 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2430 retries++;
2431 if (retries < 20) {
2432 usleep_range(10000, 20000);
2433 goto retry;
2434 }
2435 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2436 ret = -EINVAL;
2437 goto fail;
2438 }
2439 ret = 0;
2440 fail:
2441 return ret;
2442 }
2443
2444
2445 /**
2446 * drm_dp_check_act_status() - Check ACT handled status.
2447 * @mgr: manager to use
2448 *
2449 * Check the payload status bits in the DPCD for ACT handled completion.
2450 */
2451 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2452 {
2453 u8 status;
2454 int ret;
2455 int count = 0;
2456
2457 do {
2458 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2459
2460 if (ret < 0) {
2461 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2462 goto fail;
2463 }
2464
2465 if (status & DP_PAYLOAD_ACT_HANDLED)
2466 break;
2467 count++;
2468 udelay(100);
2469
2470 } while (count < 30);
2471
2472 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2473 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2474 ret = -EINVAL;
2475 goto fail;
2476 }
2477 return 0;
2478 fail:
2479 return ret;
2480 }
2481 EXPORT_SYMBOL(drm_dp_check_act_status);
2482
2483 /**
2484 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2485 * @clock: dot clock for the mode
2486 * @bpp: bpp for the mode.
2487 *
2488 * This uses the formula in the spec to calculate the PBN value for a mode.
2489 */
2490 int drm_dp_calc_pbn_mode(int clock, int bpp)
2491 {
2492 fixed20_12 pix_bw;
2493 fixed20_12 fbpp;
2494 fixed20_12 result;
2495 fixed20_12 margin, tmp;
2496 u32 res;
2497
2498 pix_bw.full = dfixed_const(clock);
2499 fbpp.full = dfixed_const(bpp);
2500 tmp.full = dfixed_const(8);
2501 fbpp.full = dfixed_div(fbpp, tmp);
2502
2503 result.full = dfixed_mul(pix_bw, fbpp);
2504 margin.full = dfixed_const(54);
2505 tmp.full = dfixed_const(64);
2506 margin.full = dfixed_div(margin, tmp);
2507 result.full = dfixed_div(result, margin);
2508
2509 margin.full = dfixed_const(1006);
2510 tmp.full = dfixed_const(1000);
2511 margin.full = dfixed_div(margin, tmp);
2512 result.full = dfixed_mul(result, margin);
2513
2514 result.full = dfixed_div(result, tmp);
2515 result.full = dfixed_ceil(result);
2516 res = dfixed_trunc(result);
2517 return res;
2518 }
2519 EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2520
2521 static int test_calc_pbn_mode(void)
2522 {
2523 int ret;
2524 ret = drm_dp_calc_pbn_mode(154000, 30);
2525 if (ret != 689)
2526 return -EINVAL;
2527 ret = drm_dp_calc_pbn_mode(234000, 30);
2528 if (ret != 1047)
2529 return -EINVAL;
2530 return 0;
2531 }
2532
2533 /* we want to kick the TX after we've ack the up/down IRQs. */
2534 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2535 {
2536 queue_work(system_long_wq, &mgr->tx_work);
2537 }
2538
2539 static void drm_dp_mst_dump_mstb(struct seq_file *m,
2540 struct drm_dp_mst_branch *mstb)
2541 {
2542 struct drm_dp_mst_port *port;
2543 int tabs = mstb->lct;
2544 char prefix[10];
2545 int i;
2546
2547 for (i = 0; i < tabs; i++)
2548 prefix[i] = '\t';
2549 prefix[i] = '\0';
2550
2551 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2552 list_for_each_entry(port, &mstb->ports, next) {
2553 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2554 if (port->mstb)
2555 drm_dp_mst_dump_mstb(m, port->mstb);
2556 }
2557 }
2558
2559 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2560 char *buf)
2561 {
2562 int ret;
2563 int i;
2564 for (i = 0; i < 4; i++) {
2565 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2566 if (ret != 16)
2567 break;
2568 }
2569 if (i == 4)
2570 return true;
2571 return false;
2572 }
2573
2574 /**
2575 * drm_dp_mst_dump_topology(): dump topology to seq file.
2576 * @m: seq_file to dump output to
2577 * @mgr: manager to dump current topology for.
2578 *
2579 * helper to dump MST topology to a seq file for debugfs.
2580 */
2581 void drm_dp_mst_dump_topology(struct seq_file *m,
2582 struct drm_dp_mst_topology_mgr *mgr)
2583 {
2584 int i;
2585 struct drm_dp_mst_port *port;
2586 mutex_lock(&mgr->lock);
2587 if (mgr->mst_primary)
2588 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2589
2590 /* dump VCPIs */
2591 mutex_unlock(&mgr->lock);
2592
2593 mutex_lock(&mgr->payload_lock);
2594 seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask);
2595
2596 for (i = 0; i < mgr->max_payloads; i++) {
2597 if (mgr->proposed_vcpis[i]) {
2598 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2599 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2600 } else
2601 seq_printf(m, "vcpi %d:unsed\n", i);
2602 }
2603 for (i = 0; i < mgr->max_payloads; i++) {
2604 seq_printf(m, "payload %d: %d, %d, %d\n",
2605 i,
2606 mgr->payloads[i].payload_state,
2607 mgr->payloads[i].start_slot,
2608 mgr->payloads[i].num_slots);
2609
2610
2611 }
2612 mutex_unlock(&mgr->payload_lock);
2613
2614 mutex_lock(&mgr->lock);
2615 if (mgr->mst_primary) {
2616 u8 buf[64];
2617 bool bret;
2618 int ret;
2619 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2620 seq_printf(m, "dpcd: ");
2621 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2622 seq_printf(m, "%02x ", buf[i]);
2623 seq_printf(m, "\n");
2624 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2625 seq_printf(m, "faux/mst: ");
2626 for (i = 0; i < 2; i++)
2627 seq_printf(m, "%02x ", buf[i]);
2628 seq_printf(m, "\n");
2629 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2630 seq_printf(m, "mst ctrl: ");
2631 for (i = 0; i < 1; i++)
2632 seq_printf(m, "%02x ", buf[i]);
2633 seq_printf(m, "\n");
2634
2635 bret = dump_dp_payload_table(mgr, buf);
2636 if (bret == true) {
2637 seq_printf(m, "payload table: ");
2638 for (i = 0; i < 63; i++)
2639 seq_printf(m, "%02x ", buf[i]);
2640 seq_printf(m, "\n");
2641 }
2642
2643 }
2644
2645 mutex_unlock(&mgr->lock);
2646
2647 }
2648 EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2649
2650 static void drm_dp_tx_work(struct work_struct *work)
2651 {
2652 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2653
2654 mutex_lock(&mgr->qlock);
2655 if (mgr->tx_down_in_progress)
2656 process_single_down_tx_qlock(mgr);
2657 mutex_unlock(&mgr->qlock);
2658 }
2659
2660 static void drm_dp_destroy_connector_work(struct work_struct *work)
2661 {
2662 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
2663 struct drm_connector *connector;
2664
2665 /*
2666 * Not a regular list traverse as we have to drop the destroy
2667 * connector lock before destroying the connector, to avoid AB->BA
2668 * ordering between this lock and the config mutex.
2669 */
2670 for (;;) {
2671 mutex_lock(&mgr->destroy_connector_lock);
2672 connector = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_connector, destroy_list);
2673 if (!connector) {
2674 mutex_unlock(&mgr->destroy_connector_lock);
2675 break;
2676 }
2677 list_del(&connector->destroy_list);
2678 mutex_unlock(&mgr->destroy_connector_lock);
2679
2680 mgr->cbs->destroy_connector(mgr, connector);
2681 }
2682 }
2683
2684 /**
2685 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2686 * @mgr: manager struct to initialise
2687 * @dev: device providing this structure - for i2c addition.
2688 * @aux: DP helper aux channel to talk to this device
2689 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2690 * @max_payloads: maximum number of payloads this GPU can source
2691 * @conn_base_id: the connector object ID the MST device is connected to.
2692 *
2693 * Return 0 for success, or negative error code on failure
2694 */
2695 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2696 struct device *dev, struct drm_dp_aux *aux,
2697 int max_dpcd_transaction_bytes,
2698 int max_payloads, int conn_base_id)
2699 {
2700 mutex_init(&mgr->lock);
2701 mutex_init(&mgr->qlock);
2702 mutex_init(&mgr->payload_lock);
2703 mutex_init(&mgr->destroy_connector_lock);
2704 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2705 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2706 INIT_LIST_HEAD(&mgr->destroy_connector_list);
2707 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2708 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2709 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work);
2710 init_waitqueue_head(&mgr->tx_waitq);
2711 mgr->dev = dev;
2712 mgr->aux = aux;
2713 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2714 mgr->max_payloads = max_payloads;
2715 mgr->conn_base_id = conn_base_id;
2716 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2717 if (!mgr->payloads)
2718 return -ENOMEM;
2719 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2720 if (!mgr->proposed_vcpis)
2721 return -ENOMEM;
2722 set_bit(0, &mgr->payload_mask);
2723 test_calc_pbn_mode();
2724 return 0;
2725 }
2726 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2727
2728 /**
2729 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2730 * @mgr: manager to destroy
2731 */
2732 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2733 {
2734 flush_work(&mgr->work);
2735 flush_work(&mgr->destroy_connector_work);
2736 mutex_lock(&mgr->payload_lock);
2737 kfree(mgr->payloads);
2738 mgr->payloads = NULL;
2739 kfree(mgr->proposed_vcpis);
2740 mgr->proposed_vcpis = NULL;
2741 mutex_unlock(&mgr->payload_lock);
2742 mgr->dev = NULL;
2743 mgr->aux = NULL;
2744 }
2745 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2746
2747 /* I2C device */
2748 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2749 int num)
2750 {
2751 struct drm_dp_aux *aux = adapter->algo_data;
2752 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2753 struct drm_dp_mst_branch *mstb;
2754 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2755 unsigned int i;
2756 bool reading = false;
2757 struct drm_dp_sideband_msg_req_body msg;
2758 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2759 int ret;
2760
2761 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2762 if (!mstb)
2763 return -EREMOTEIO;
2764
2765 /* construct i2c msg */
2766 /* see if last msg is a read */
2767 if (msgs[num - 1].flags & I2C_M_RD)
2768 reading = true;
2769
2770 if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) {
2771 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2772 ret = -EIO;
2773 goto out;
2774 }
2775
2776 memset(&msg, 0, sizeof(msg));
2777 msg.req_type = DP_REMOTE_I2C_READ;
2778 msg.u.i2c_read.num_transactions = num - 1;
2779 msg.u.i2c_read.port_number = port->port_num;
2780 for (i = 0; i < num - 1; i++) {
2781 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2782 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2783 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2784 }
2785 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2786 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2787
2788 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2789 if (!txmsg) {
2790 ret = -ENOMEM;
2791 goto out;
2792 }
2793
2794 txmsg->dst = mstb;
2795 drm_dp_encode_sideband_req(&msg, txmsg);
2796
2797 drm_dp_queue_down_tx(mgr, txmsg);
2798
2799 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2800 if (ret > 0) {
2801
2802 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2803 ret = -EREMOTEIO;
2804 goto out;
2805 }
2806 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2807 ret = -EIO;
2808 goto out;
2809 }
2810 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2811 ret = num;
2812 }
2813 out:
2814 kfree(txmsg);
2815 drm_dp_put_mst_branch_device(mstb);
2816 return ret;
2817 }
2818
2819 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2820 {
2821 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2822 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2823 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2824 I2C_FUNC_10BIT_ADDR;
2825 }
2826
2827 static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2828 .functionality = drm_dp_mst_i2c_functionality,
2829 .master_xfer = drm_dp_mst_i2c_xfer,
2830 };
2831
2832 /**
2833 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2834 * @aux: DisplayPort AUX channel
2835 *
2836 * Returns 0 on success or a negative error code on failure.
2837 */
2838 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2839 {
2840 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2841 aux->ddc.algo_data = aux;
2842 aux->ddc.retries = 3;
2843
2844 aux->ddc.class = I2C_CLASS_DDC;
2845 aux->ddc.owner = THIS_MODULE;
2846 aux->ddc.dev.parent = aux->dev;
2847 aux->ddc.dev.of_node = aux->dev->of_node;
2848
2849 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2850 sizeof(aux->ddc.name));
2851
2852 return i2c_add_adapter(&aux->ddc);
2853 }
2854
2855 /**
2856 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2857 * @aux: DisplayPort AUX channel
2858 */
2859 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2860 {
2861 i2c_del_adapter(&aux->ddc);
2862 }
Linux with added FPC-III support