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ARM: pmu: add support for interrupt-affinity property
[linux/fpc-iii.git] / drivers / gpu / drm / drm_dp_mst_topology.c
blob379ab45557568c6e21615526a96a60e145ed1ee5
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 cancel_work_sync(&mstb->mgr->work);
808
809 /*
810 * destroy all ports - don't need lock
811 * as there are no more references to the mst branch
812 * device at this point.
813 */
814 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
815 list_del(&port->next);
816 drm_dp_put_port(port);
817 }
818
819 /* drop any tx slots msg */
820 mutex_lock(&mstb->mgr->qlock);
821 if (mstb->tx_slots[0]) {
822 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
823 mstb->tx_slots[0] = NULL;
824 wake_tx = true;
825 }
826 if (mstb->tx_slots[1]) {
827 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
828 mstb->tx_slots[1] = NULL;
829 wake_tx = true;
830 }
831 mutex_unlock(&mstb->mgr->qlock);
832
833 if (wake_tx)
834 wake_up(&mstb->mgr->tx_waitq);
835 kfree(mstb);
836 }
837
838 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
839 {
840 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
841 }
842
843
844 static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
845 {
846 struct drm_dp_mst_branch *mstb;
847
848 switch (old_pdt) {
849 case DP_PEER_DEVICE_DP_LEGACY_CONV:
850 case DP_PEER_DEVICE_SST_SINK:
851 /* remove i2c over sideband */
852 drm_dp_mst_unregister_i2c_bus(&port->aux);
853 break;
854 case DP_PEER_DEVICE_MST_BRANCHING:
855 mstb = port->mstb;
856 port->mstb = NULL;
857 drm_dp_put_mst_branch_device(mstb);
858 break;
859 }
860 }
861
862 static void drm_dp_destroy_port(struct kref *kref)
863 {
864 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
865 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
866 if (!port->input) {
867 port->vcpi.num_slots = 0;
868
869 kfree(port->cached_edid);
870 if (port->connector)
871 (*port->mgr->cbs->destroy_connector)(mgr, port->connector);
872 drm_dp_port_teardown_pdt(port, port->pdt);
873
874 if (!port->input && port->vcpi.vcpi > 0)
875 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
876 }
877 kfree(port);
878
879 (*mgr->cbs->hotplug)(mgr);
880 }
881
882 static void drm_dp_put_port(struct drm_dp_mst_port *port)
883 {
884 kref_put(&port->kref, drm_dp_destroy_port);
885 }
886
887 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)
888 {
889 struct drm_dp_mst_port *port;
890 struct drm_dp_mst_branch *rmstb;
891 if (to_find == mstb) {
892 kref_get(&mstb->kref);
893 return mstb;
894 }
895 list_for_each_entry(port, &mstb->ports, next) {
896 if (port->mstb) {
897 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
898 if (rmstb)
899 return rmstb;
900 }
901 }
902 return NULL;
903 }
904
905 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)
906 {
907 struct drm_dp_mst_branch *rmstb = NULL;
908 mutex_lock(&mgr->lock);
909 if (mgr->mst_primary)
910 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
911 mutex_unlock(&mgr->lock);
912 return rmstb;
913 }
914
915 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)
916 {
917 struct drm_dp_mst_port *port, *mport;
918
919 list_for_each_entry(port, &mstb->ports, next) {
920 if (port == to_find) {
921 kref_get(&port->kref);
922 return port;
923 }
924 if (port->mstb) {
925 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
926 if (mport)
927 return mport;
928 }
929 }
930 return NULL;
931 }
932
933 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)
934 {
935 struct drm_dp_mst_port *rport = NULL;
936 mutex_lock(&mgr->lock);
937 if (mgr->mst_primary)
938 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
939 mutex_unlock(&mgr->lock);
940 return rport;
941 }
942
943 static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
944 {
945 struct drm_dp_mst_port *port;
946
947 list_for_each_entry(port, &mstb->ports, next) {
948 if (port->port_num == port_num) {
949 kref_get(&port->kref);
950 return port;
951 }
952 }
953
954 return NULL;
955 }
956
957 /*
958 * calculate a new RAD for this MST branch device
959 * if parent has an LCT of 2 then it has 1 nibble of RAD,
960 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
961 */
962 static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
963 u8 *rad)
964 {
965 int lct = port->parent->lct;
966 int shift = 4;
967 int idx = lct / 2;
968 if (lct > 1) {
969 memcpy(rad, port->parent->rad, idx);
970 shift = (lct % 2) ? 4 : 0;
971 } else
972 rad[0] = 0;
973
974 rad[idx] |= port->port_num << shift;
975 return lct + 1;
976 }
977
978 /*
979 * return sends link address for new mstb
980 */
981 static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
982 {
983 int ret;
984 u8 rad[6], lct;
985 bool send_link = false;
986 switch (port->pdt) {
987 case DP_PEER_DEVICE_DP_LEGACY_CONV:
988 case DP_PEER_DEVICE_SST_SINK:
989 /* add i2c over sideband */
990 ret = drm_dp_mst_register_i2c_bus(&port->aux);
991 break;
992 case DP_PEER_DEVICE_MST_BRANCHING:
993 lct = drm_dp_calculate_rad(port, rad);
994
995 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
996 port->mstb->mgr = port->mgr;
997 port->mstb->port_parent = port;
998
999 send_link = true;
1000 break;
1001 }
1002 return send_link;
1003 }
1004
1005 static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
1006 struct drm_dp_mst_port *port)
1007 {
1008 int ret;
1009 if (port->dpcd_rev >= 0x12) {
1010 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
1011 if (!port->guid_valid) {
1012 ret = drm_dp_send_dpcd_write(mstb->mgr,
1013 port,
1014 DP_GUID,
1015 16, port->guid);
1016 port->guid_valid = true;
1017 }
1018 }
1019 }
1020
1021 static void build_mst_prop_path(struct drm_dp_mst_port *port,
1022 struct drm_dp_mst_branch *mstb,
1023 char *proppath,
1024 size_t proppath_size)
1025 {
1026 int i;
1027 char temp[8];
1028 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
1029 for (i = 0; i < (mstb->lct - 1); i++) {
1030 int shift = (i % 2) ? 0 : 4;
1031 int port_num = mstb->rad[i / 2] >> shift;
1032 snprintf(temp, sizeof(temp), "-%d", port_num);
1033 strlcat(proppath, temp, proppath_size);
1034 }
1035 snprintf(temp, sizeof(temp), "-%d", port->port_num);
1036 strlcat(proppath, temp, proppath_size);
1037 }
1038
1039 static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1040 struct device *dev,
1041 struct drm_dp_link_addr_reply_port *port_msg)
1042 {
1043 struct drm_dp_mst_port *port;
1044 bool ret;
1045 bool created = false;
1046 int old_pdt = 0;
1047 int old_ddps = 0;
1048 port = drm_dp_get_port(mstb, port_msg->port_number);
1049 if (!port) {
1050 port = kzalloc(sizeof(*port), GFP_KERNEL);
1051 if (!port)
1052 return;
1053 kref_init(&port->kref);
1054 port->parent = mstb;
1055 port->port_num = port_msg->port_number;
1056 port->mgr = mstb->mgr;
1057 port->aux.name = "DPMST";
1058 port->aux.dev = dev;
1059 created = true;
1060 } else {
1061 old_pdt = port->pdt;
1062 old_ddps = port->ddps;
1063 }
1064
1065 port->pdt = port_msg->peer_device_type;
1066 port->input = port_msg->input_port;
1067 port->mcs = port_msg->mcs;
1068 port->ddps = port_msg->ddps;
1069 port->ldps = port_msg->legacy_device_plug_status;
1070 port->dpcd_rev = port_msg->dpcd_revision;
1071 port->num_sdp_streams = port_msg->num_sdp_streams;
1072 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1073 memcpy(port->guid, port_msg->peer_guid, 16);
1074
1075 /* manage mstb port lists with mgr lock - take a reference
1076 for this list */
1077 if (created) {
1078 mutex_lock(&mstb->mgr->lock);
1079 kref_get(&port->kref);
1080 list_add(&port->next, &mstb->ports);
1081 mutex_unlock(&mstb->mgr->lock);
1082 }
1083
1084 if (old_ddps != port->ddps) {
1085 if (port->ddps) {
1086 drm_dp_check_port_guid(mstb, port);
1087 if (!port->input)
1088 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1089 } else {
1090 port->guid_valid = false;
1091 port->available_pbn = 0;
1092 }
1093 }
1094
1095 if (old_pdt != port->pdt && !port->input) {
1096 drm_dp_port_teardown_pdt(port, old_pdt);
1097
1098 ret = drm_dp_port_setup_pdt(port);
1099 if (ret == true) {
1100 drm_dp_send_link_address(mstb->mgr, port->mstb);
1101 port->mstb->link_address_sent = true;
1102 }
1103 }
1104
1105 if (created && !port->input) {
1106 char proppath[255];
1107 build_mst_prop_path(port, mstb, proppath, sizeof(proppath));
1108 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1109
1110 if (port->port_num >= 8) {
1111 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc);
1112 }
1113 }
1114
1115 /* put reference to this port */
1116 drm_dp_put_port(port);
1117 }
1118
1119 static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1120 struct drm_dp_connection_status_notify *conn_stat)
1121 {
1122 struct drm_dp_mst_port *port;
1123 int old_pdt;
1124 int old_ddps;
1125 bool dowork = false;
1126 port = drm_dp_get_port(mstb, conn_stat->port_number);
1127 if (!port)
1128 return;
1129
1130 old_ddps = port->ddps;
1131 old_pdt = port->pdt;
1132 port->pdt = conn_stat->peer_device_type;
1133 port->mcs = conn_stat->message_capability_status;
1134 port->ldps = conn_stat->legacy_device_plug_status;
1135 port->ddps = conn_stat->displayport_device_plug_status;
1136
1137 if (old_ddps != port->ddps) {
1138 if (port->ddps) {
1139 drm_dp_check_port_guid(mstb, port);
1140 dowork = true;
1141 } else {
1142 port->guid_valid = false;
1143 port->available_pbn = 0;
1144 }
1145 }
1146 if (old_pdt != port->pdt && !port->input) {
1147 drm_dp_port_teardown_pdt(port, old_pdt);
1148
1149 if (drm_dp_port_setup_pdt(port))
1150 dowork = true;
1151 }
1152
1153 drm_dp_put_port(port);
1154 if (dowork)
1155 queue_work(system_long_wq, &mstb->mgr->work);
1156
1157 }
1158
1159 static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1160 u8 lct, u8 *rad)
1161 {
1162 struct drm_dp_mst_branch *mstb;
1163 struct drm_dp_mst_port *port;
1164 int i;
1165 /* find the port by iterating down */
1166 mstb = mgr->mst_primary;
1167
1168 for (i = 0; i < lct - 1; i++) {
1169 int shift = (i % 2) ? 0 : 4;
1170 int port_num = rad[i / 2] >> shift;
1171
1172 list_for_each_entry(port, &mstb->ports, next) {
1173 if (port->port_num == port_num) {
1174 if (!port->mstb) {
1175 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1176 return NULL;
1177 }
1178
1179 mstb = port->mstb;
1180 break;
1181 }
1182 }
1183 }
1184 kref_get(&mstb->kref);
1185 return mstb;
1186 }
1187
1188 static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1189 struct drm_dp_mst_branch *mstb)
1190 {
1191 struct drm_dp_mst_port *port;
1192
1193 if (!mstb->link_address_sent) {
1194 drm_dp_send_link_address(mgr, mstb);
1195 mstb->link_address_sent = true;
1196 }
1197 list_for_each_entry(port, &mstb->ports, next) {
1198 if (port->input)
1199 continue;
1200
1201 if (!port->ddps)
1202 continue;
1203
1204 if (!port->available_pbn)
1205 drm_dp_send_enum_path_resources(mgr, mstb, port);
1206
1207 if (port->mstb)
1208 drm_dp_check_and_send_link_address(mgr, port->mstb);
1209 }
1210 }
1211
1212 static void drm_dp_mst_link_probe_work(struct work_struct *work)
1213 {
1214 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1215
1216 drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
1217
1218 }
1219
1220 static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1221 u8 *guid)
1222 {
1223 static u8 zero_guid[16];
1224
1225 if (!memcmp(guid, zero_guid, 16)) {
1226 u64 salt = get_jiffies_64();
1227 memcpy(&guid[0], &salt, sizeof(u64));
1228 memcpy(&guid[8], &salt, sizeof(u64));
1229 return false;
1230 }
1231 return true;
1232 }
1233
1234 #if 0
1235 static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1236 {
1237 struct drm_dp_sideband_msg_req_body req;
1238
1239 req.req_type = DP_REMOTE_DPCD_READ;
1240 req.u.dpcd_read.port_number = port_num;
1241 req.u.dpcd_read.dpcd_address = offset;
1242 req.u.dpcd_read.num_bytes = num_bytes;
1243 drm_dp_encode_sideband_req(&req, msg);
1244
1245 return 0;
1246 }
1247 #endif
1248
1249 static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1250 bool up, u8 *msg, int len)
1251 {
1252 int ret;
1253 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1254 int tosend, total, offset;
1255 int retries = 0;
1256
1257 retry:
1258 total = len;
1259 offset = 0;
1260 do {
1261 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1262
1263 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1264 &msg[offset],
1265 tosend);
1266 if (ret != tosend) {
1267 if (ret == -EIO && retries < 5) {
1268 retries++;
1269 goto retry;
1270 }
1271 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1272 WARN(1, "fail\n");
1273
1274 return -EIO;
1275 }
1276 offset += tosend;
1277 total -= tosend;
1278 } while (total > 0);
1279 return 0;
1280 }
1281
1282 static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1283 struct drm_dp_sideband_msg_tx *txmsg)
1284 {
1285 struct drm_dp_mst_branch *mstb = txmsg->dst;
1286
1287 /* both msg slots are full */
1288 if (txmsg->seqno == -1) {
1289 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1290 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1291 return -EAGAIN;
1292 }
1293 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1294 txmsg->seqno = mstb->last_seqno;
1295 mstb->last_seqno ^= 1;
1296 } else if (mstb->tx_slots[0] == NULL)
1297 txmsg->seqno = 0;
1298 else
1299 txmsg->seqno = 1;
1300 mstb->tx_slots[txmsg->seqno] = txmsg;
1301 }
1302 hdr->broadcast = 0;
1303 hdr->path_msg = txmsg->path_msg;
1304 hdr->lct = mstb->lct;
1305 hdr->lcr = mstb->lct - 1;
1306 if (mstb->lct > 1)
1307 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1308 hdr->seqno = txmsg->seqno;
1309 return 0;
1310 }
1311 /*
1312 * process a single block of the next message in the sideband queue
1313 */
1314 static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1315 struct drm_dp_sideband_msg_tx *txmsg,
1316 bool up)
1317 {
1318 u8 chunk[48];
1319 struct drm_dp_sideband_msg_hdr hdr;
1320 int len, space, idx, tosend;
1321 int ret;
1322
1323 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1324
1325 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1326 txmsg->seqno = -1;
1327 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1328 }
1329
1330 /* make hdr from dst mst - for replies use seqno
1331 otherwise assign one */
1332 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1333 if (ret < 0)
1334 return ret;
1335
1336 /* amount left to send in this message */
1337 len = txmsg->cur_len - txmsg->cur_offset;
1338
1339 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1340 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1341
1342 tosend = min(len, space);
1343 if (len == txmsg->cur_len)
1344 hdr.somt = 1;
1345 if (space >= len)
1346 hdr.eomt = 1;
1347
1348
1349 hdr.msg_len = tosend + 1;
1350 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1351 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1352 /* add crc at end */
1353 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1354 idx += tosend + 1;
1355
1356 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1357 if (ret) {
1358 DRM_DEBUG_KMS("sideband msg failed to send\n");
1359 return ret;
1360 }
1361
1362 txmsg->cur_offset += tosend;
1363 if (txmsg->cur_offset == txmsg->cur_len) {
1364 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1365 return 1;
1366 }
1367 return 0;
1368 }
1369
1370 static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1371 {
1372 struct drm_dp_sideband_msg_tx *txmsg;
1373 int ret;
1374
1375 WARN_ON(!mutex_is_locked(&mgr->qlock));
1376
1377 /* construct a chunk from the first msg in the tx_msg queue */
1378 if (list_empty(&mgr->tx_msg_downq)) {
1379 mgr->tx_down_in_progress = false;
1380 return;
1381 }
1382 mgr->tx_down_in_progress = true;
1383
1384 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1385 ret = process_single_tx_qlock(mgr, txmsg, false);
1386 if (ret == 1) {
1387 /* txmsg is sent it should be in the slots now */
1388 list_del(&txmsg->next);
1389 } else if (ret) {
1390 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1391 list_del(&txmsg->next);
1392 if (txmsg->seqno != -1)
1393 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1394 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1395 wake_up(&mgr->tx_waitq);
1396 }
1397 if (list_empty(&mgr->tx_msg_downq)) {
1398 mgr->tx_down_in_progress = false;
1399 return;
1400 }
1401 }
1402
1403 /* called holding qlock */
1404 static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1405 {
1406 struct drm_dp_sideband_msg_tx *txmsg;
1407 int ret;
1408
1409 /* construct a chunk from the first msg in the tx_msg queue */
1410 if (list_empty(&mgr->tx_msg_upq)) {
1411 mgr->tx_up_in_progress = false;
1412 return;
1413 }
1414
1415 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1416 ret = process_single_tx_qlock(mgr, txmsg, true);
1417 if (ret == 1) {
1418 /* up txmsgs aren't put in slots - so free after we send it */
1419 list_del(&txmsg->next);
1420 kfree(txmsg);
1421 } else if (ret)
1422 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1423 mgr->tx_up_in_progress = true;
1424 }
1425
1426 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1427 struct drm_dp_sideband_msg_tx *txmsg)
1428 {
1429 mutex_lock(&mgr->qlock);
1430 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1431 if (!mgr->tx_down_in_progress)
1432 process_single_down_tx_qlock(mgr);
1433 mutex_unlock(&mgr->qlock);
1434 }
1435
1436 static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1437 struct drm_dp_mst_branch *mstb)
1438 {
1439 int len;
1440 struct drm_dp_sideband_msg_tx *txmsg;
1441 int ret;
1442
1443 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1444 if (!txmsg)
1445 return -ENOMEM;
1446
1447 txmsg->dst = mstb;
1448 len = build_link_address(txmsg);
1449
1450 drm_dp_queue_down_tx(mgr, txmsg);
1451
1452 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1453 if (ret > 0) {
1454 int i;
1455
1456 if (txmsg->reply.reply_type == 1)
1457 DRM_DEBUG_KMS("link address nak received\n");
1458 else {
1459 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1460 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1461 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,
1462 txmsg->reply.u.link_addr.ports[i].input_port,
1463 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1464 txmsg->reply.u.link_addr.ports[i].port_number,
1465 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1466 txmsg->reply.u.link_addr.ports[i].mcs,
1467 txmsg->reply.u.link_addr.ports[i].ddps,
1468 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1469 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1470 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1471 }
1472 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1473 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1474 }
1475 (*mgr->cbs->hotplug)(mgr);
1476 }
1477 } else
1478 DRM_DEBUG_KMS("link address failed %d\n", ret);
1479
1480 kfree(txmsg);
1481 return 0;
1482 }
1483
1484 static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1485 struct drm_dp_mst_branch *mstb,
1486 struct drm_dp_mst_port *port)
1487 {
1488 int len;
1489 struct drm_dp_sideband_msg_tx *txmsg;
1490 int ret;
1491
1492 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1493 if (!txmsg)
1494 return -ENOMEM;
1495
1496 txmsg->dst = mstb;
1497 len = build_enum_path_resources(txmsg, port->port_num);
1498
1499 drm_dp_queue_down_tx(mgr, txmsg);
1500
1501 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1502 if (ret > 0) {
1503 if (txmsg->reply.reply_type == 1)
1504 DRM_DEBUG_KMS("enum path resources nak received\n");
1505 else {
1506 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1507 DRM_ERROR("got incorrect port in response\n");
1508 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,
1509 txmsg->reply.u.path_resources.avail_payload_bw_number);
1510 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1511 }
1512 }
1513
1514 kfree(txmsg);
1515 return 0;
1516 }
1517
1518 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1519 struct drm_dp_mst_port *port,
1520 int id,
1521 int pbn)
1522 {
1523 struct drm_dp_sideband_msg_tx *txmsg;
1524 struct drm_dp_mst_branch *mstb;
1525 int len, ret;
1526
1527 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1528 if (!mstb)
1529 return -EINVAL;
1530
1531 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1532 if (!txmsg) {
1533 ret = -ENOMEM;
1534 goto fail_put;
1535 }
1536
1537 txmsg->dst = mstb;
1538 len = build_allocate_payload(txmsg, port->port_num,
1539 id,
1540 pbn);
1541
1542 drm_dp_queue_down_tx(mgr, txmsg);
1543
1544 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1545 if (ret > 0) {
1546 if (txmsg->reply.reply_type == 1) {
1547 ret = -EINVAL;
1548 } else
1549 ret = 0;
1550 }
1551 kfree(txmsg);
1552 fail_put:
1553 drm_dp_put_mst_branch_device(mstb);
1554 return ret;
1555 }
1556
1557 static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1558 int id,
1559 struct drm_dp_payload *payload)
1560 {
1561 int ret;
1562
1563 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1564 if (ret < 0) {
1565 payload->payload_state = 0;
1566 return ret;
1567 }
1568 payload->payload_state = DP_PAYLOAD_LOCAL;
1569 return 0;
1570 }
1571
1572 static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1573 struct drm_dp_mst_port *port,
1574 int id,
1575 struct drm_dp_payload *payload)
1576 {
1577 int ret;
1578 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1579 if (ret < 0)
1580 return ret;
1581 payload->payload_state = DP_PAYLOAD_REMOTE;
1582 return ret;
1583 }
1584
1585 static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1586 struct drm_dp_mst_port *port,
1587 int id,
1588 struct drm_dp_payload *payload)
1589 {
1590 DRM_DEBUG_KMS("\n");
1591 /* its okay for these to fail */
1592 if (port) {
1593 drm_dp_payload_send_msg(mgr, port, id, 0);
1594 }
1595
1596 drm_dp_dpcd_write_payload(mgr, id, payload);
1597 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
1598 return 0;
1599 }
1600
1601 static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1602 int id,
1603 struct drm_dp_payload *payload)
1604 {
1605 payload->payload_state = 0;
1606 return 0;
1607 }
1608
1609 /**
1610 * drm_dp_update_payload_part1() - Execute payload update part 1
1611 * @mgr: manager to use.
1612 *
1613 * This iterates over all proposed virtual channels, and tries to
1614 * allocate space in the link for them. For 0->slots transitions,
1615 * this step just writes the VCPI to the MST device. For slots->0
1616 * transitions, this writes the updated VCPIs and removes the
1617 * remote VC payloads.
1618 *
1619 * after calling this the driver should generate ACT and payload
1620 * packets.
1621 */
1622 int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1623 {
1624 int i, j;
1625 int cur_slots = 1;
1626 struct drm_dp_payload req_payload;
1627 struct drm_dp_mst_port *port;
1628
1629 mutex_lock(&mgr->payload_lock);
1630 for (i = 0; i < mgr->max_payloads; i++) {
1631 /* solve the current payloads - compare to the hw ones
1632 - update the hw view */
1633 req_payload.start_slot = cur_slots;
1634 if (mgr->proposed_vcpis[i]) {
1635 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1636 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1637 } else {
1638 port = NULL;
1639 req_payload.num_slots = 0;
1640 }
1641
1642 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1643 mgr->payloads[i].start_slot = req_payload.start_slot;
1644 }
1645 /* work out what is required to happen with this payload */
1646 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
1647
1648 /* need to push an update for this payload */
1649 if (req_payload.num_slots) {
1650 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
1651 mgr->payloads[i].num_slots = req_payload.num_slots;
1652 } else if (mgr->payloads[i].num_slots) {
1653 mgr->payloads[i].num_slots = 0;
1654 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
1655 req_payload.payload_state = mgr->payloads[i].payload_state;
1656 mgr->payloads[i].start_slot = 0;
1657 }
1658 mgr->payloads[i].payload_state = req_payload.payload_state;
1659 }
1660 cur_slots += req_payload.num_slots;
1661 }
1662
1663 for (i = 0; i < mgr->max_payloads; i++) {
1664 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1665 DRM_DEBUG_KMS("removing payload %d\n", i);
1666 for (j = i; j < mgr->max_payloads - 1; j++) {
1667 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1668 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1669 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1670 set_bit(j + 1, &mgr->payload_mask);
1671 } else {
1672 clear_bit(j + 1, &mgr->payload_mask);
1673 }
1674 }
1675 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1676 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1677 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1678
1679 }
1680 }
1681 mutex_unlock(&mgr->payload_lock);
1682
1683 return 0;
1684 }
1685 EXPORT_SYMBOL(drm_dp_update_payload_part1);
1686
1687 /**
1688 * drm_dp_update_payload_part2() - Execute payload update part 2
1689 * @mgr: manager to use.
1690 *
1691 * This iterates over all proposed virtual channels, and tries to
1692 * allocate space in the link for them. For 0->slots transitions,
1693 * this step writes the remote VC payload commands. For slots->0
1694 * this just resets some internal state.
1695 */
1696 int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1697 {
1698 struct drm_dp_mst_port *port;
1699 int i;
1700 int ret = 0;
1701 mutex_lock(&mgr->payload_lock);
1702 for (i = 0; i < mgr->max_payloads; i++) {
1703
1704 if (!mgr->proposed_vcpis[i])
1705 continue;
1706
1707 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1708
1709 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1710 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1711 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1712 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1713 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
1714 }
1715 if (ret) {
1716 mutex_unlock(&mgr->payload_lock);
1717 return ret;
1718 }
1719 }
1720 mutex_unlock(&mgr->payload_lock);
1721 return 0;
1722 }
1723 EXPORT_SYMBOL(drm_dp_update_payload_part2);
1724
1725 #if 0 /* unused as of yet */
1726 static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1727 struct drm_dp_mst_port *port,
1728 int offset, int size)
1729 {
1730 int len;
1731 struct drm_dp_sideband_msg_tx *txmsg;
1732
1733 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1734 if (!txmsg)
1735 return -ENOMEM;
1736
1737 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1738 txmsg->dst = port->parent;
1739
1740 drm_dp_queue_down_tx(mgr, txmsg);
1741
1742 return 0;
1743 }
1744 #endif
1745
1746 static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1747 struct drm_dp_mst_port *port,
1748 int offset, int size, u8 *bytes)
1749 {
1750 int len;
1751 int ret;
1752 struct drm_dp_sideband_msg_tx *txmsg;
1753 struct drm_dp_mst_branch *mstb;
1754
1755 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1756 if (!mstb)
1757 return -EINVAL;
1758
1759 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1760 if (!txmsg) {
1761 ret = -ENOMEM;
1762 goto fail_put;
1763 }
1764
1765 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1766 txmsg->dst = mstb;
1767
1768 drm_dp_queue_down_tx(mgr, txmsg);
1769
1770 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1771 if (ret > 0) {
1772 if (txmsg->reply.reply_type == 1) {
1773 ret = -EINVAL;
1774 } else
1775 ret = 0;
1776 }
1777 kfree(txmsg);
1778 fail_put:
1779 drm_dp_put_mst_branch_device(mstb);
1780 return ret;
1781 }
1782
1783 static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1784 {
1785 struct drm_dp_sideband_msg_reply_body reply;
1786
1787 reply.reply_type = 1;
1788 reply.req_type = req_type;
1789 drm_dp_encode_sideband_reply(&reply, msg);
1790 return 0;
1791 }
1792
1793 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1794 struct drm_dp_mst_branch *mstb,
1795 int req_type, int seqno, bool broadcast)
1796 {
1797 struct drm_dp_sideband_msg_tx *txmsg;
1798
1799 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1800 if (!txmsg)
1801 return -ENOMEM;
1802
1803 txmsg->dst = mstb;
1804 txmsg->seqno = seqno;
1805 drm_dp_encode_up_ack_reply(txmsg, req_type);
1806
1807 mutex_lock(&mgr->qlock);
1808 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1809 if (!mgr->tx_up_in_progress) {
1810 process_single_up_tx_qlock(mgr);
1811 }
1812 mutex_unlock(&mgr->qlock);
1813 return 0;
1814 }
1815
1816 static bool drm_dp_get_vc_payload_bw(int dp_link_bw,
1817 int dp_link_count,
1818 int *out)
1819 {
1820 switch (dp_link_bw) {
1821 default:
1822 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n",
1823 dp_link_bw, dp_link_count);
1824 return false;
1825
1826 case DP_LINK_BW_1_62:
1827 *out = 3 * dp_link_count;
1828 break;
1829 case DP_LINK_BW_2_7:
1830 *out = 5 * dp_link_count;
1831 break;
1832 case DP_LINK_BW_5_4:
1833 *out = 10 * dp_link_count;
1834 break;
1835 }
1836 return true;
1837 }
1838
1839 /**
1840 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1841 * @mgr: manager to set state for
1842 * @mst_state: true to enable MST on this connector - false to disable.
1843 *
1844 * This is called by the driver when it detects an MST capable device plugged
1845 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1846 */
1847 int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1848 {
1849 int ret = 0;
1850 struct drm_dp_mst_branch *mstb = NULL;
1851
1852 mutex_lock(&mgr->lock);
1853 if (mst_state == mgr->mst_state)
1854 goto out_unlock;
1855
1856 mgr->mst_state = mst_state;
1857 /* set the device into MST mode */
1858 if (mst_state) {
1859 WARN_ON(mgr->mst_primary);
1860
1861 /* get dpcd info */
1862 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1863 if (ret != DP_RECEIVER_CAP_SIZE) {
1864 DRM_DEBUG_KMS("failed to read DPCD\n");
1865 goto out_unlock;
1866 }
1867
1868 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1],
1869 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK,
1870 &mgr->pbn_div)) {
1871 ret = -EINVAL;
1872 goto out_unlock;
1873 }
1874
1875 mgr->total_pbn = 2560;
1876 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1877 mgr->avail_slots = mgr->total_slots;
1878
1879 /* add initial branch device at LCT 1 */
1880 mstb = drm_dp_add_mst_branch_device(1, NULL);
1881 if (mstb == NULL) {
1882 ret = -ENOMEM;
1883 goto out_unlock;
1884 }
1885 mstb->mgr = mgr;
1886
1887 /* give this the main reference */
1888 mgr->mst_primary = mstb;
1889 kref_get(&mgr->mst_primary->kref);
1890
1891 {
1892 struct drm_dp_payload reset_pay;
1893 reset_pay.start_slot = 0;
1894 reset_pay.num_slots = 0x3f;
1895 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1896 }
1897
1898 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1899 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1900 if (ret < 0) {
1901 goto out_unlock;
1902 }
1903
1904
1905 /* sort out guid */
1906 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1907 if (ret != 16) {
1908 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1909 goto out_unlock;
1910 }
1911
1912 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1913 if (!mgr->guid_valid) {
1914 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1915 mgr->guid_valid = true;
1916 }
1917
1918 queue_work(system_long_wq, &mgr->work);
1919
1920 ret = 0;
1921 } else {
1922 /* disable MST on the device */
1923 mstb = mgr->mst_primary;
1924 mgr->mst_primary = NULL;
1925 /* this can fail if the device is gone */
1926 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1927 ret = 0;
1928 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1929 mgr->payload_mask = 0;
1930 set_bit(0, &mgr->payload_mask);
1931 mgr->vcpi_mask = 0;
1932 }
1933
1934 out_unlock:
1935 mutex_unlock(&mgr->lock);
1936 if (mstb)
1937 drm_dp_put_mst_branch_device(mstb);
1938 return ret;
1939
1940 }
1941 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1942
1943 /**
1944 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1945 * @mgr: manager to suspend
1946 *
1947 * This function tells the MST device that we can't handle UP messages
1948 * anymore. This should stop it from sending any since we are suspended.
1949 */
1950 void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1951 {
1952 mutex_lock(&mgr->lock);
1953 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1954 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1955 mutex_unlock(&mgr->lock);
1956 }
1957 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1958
1959 /**
1960 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1961 * @mgr: manager to resume
1962 *
1963 * This will fetch DPCD and see if the device is still there,
1964 * if it is, it will rewrite the MSTM control bits, and return.
1965 *
1966 * if the device fails this returns -1, and the driver should do
1967 * a full MST reprobe, in case we were undocked.
1968 */
1969 int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1970 {
1971 int ret = 0;
1972
1973 mutex_lock(&mgr->lock);
1974
1975 if (mgr->mst_primary) {
1976 int sret;
1977 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1978 if (sret != DP_RECEIVER_CAP_SIZE) {
1979 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1980 ret = -1;
1981 goto out_unlock;
1982 }
1983
1984 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1985 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1986 if (ret < 0) {
1987 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1988 ret = -1;
1989 goto out_unlock;
1990 }
1991 ret = 0;
1992 } else
1993 ret = -1;
1994
1995 out_unlock:
1996 mutex_unlock(&mgr->lock);
1997 return ret;
1998 }
1999 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
2000
2001 static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
2002 {
2003 int len;
2004 u8 replyblock[32];
2005 int replylen, origlen, curreply;
2006 int ret;
2007 struct drm_dp_sideband_msg_rx *msg;
2008 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
2009 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
2010
2011 len = min(mgr->max_dpcd_transaction_bytes, 16);
2012 ret = drm_dp_dpcd_read(mgr->aux, basereg,
2013 replyblock, len);
2014 if (ret != len) {
2015 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
2016 return;
2017 }
2018 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
2019 if (!ret) {
2020 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
2021 return;
2022 }
2023 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
2024
2025 origlen = replylen;
2026 replylen -= len;
2027 curreply = len;
2028 while (replylen > 0) {
2029 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2030 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2031 replyblock, len);
2032 if (ret != len) {
2033 DRM_DEBUG_KMS("failed to read a chunk\n");
2034 }
2035 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2036 if (ret == false)
2037 DRM_DEBUG_KMS("failed to build sideband msg\n");
2038 curreply += len;
2039 replylen -= len;
2040 }
2041 }
2042
2043 static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2044 {
2045 int ret = 0;
2046
2047 drm_dp_get_one_sb_msg(mgr, false);
2048
2049 if (mgr->down_rep_recv.have_eomt) {
2050 struct drm_dp_sideband_msg_tx *txmsg;
2051 struct drm_dp_mst_branch *mstb;
2052 int slot = -1;
2053 mstb = drm_dp_get_mst_branch_device(mgr,
2054 mgr->down_rep_recv.initial_hdr.lct,
2055 mgr->down_rep_recv.initial_hdr.rad);
2056
2057 if (!mstb) {
2058 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2059 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2060 return 0;
2061 }
2062
2063 /* find the message */
2064 slot = mgr->down_rep_recv.initial_hdr.seqno;
2065 mutex_lock(&mgr->qlock);
2066 txmsg = mstb->tx_slots[slot];
2067 /* remove from slots */
2068 mutex_unlock(&mgr->qlock);
2069
2070 if (!txmsg) {
2071 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2072 mstb,
2073 mgr->down_rep_recv.initial_hdr.seqno,
2074 mgr->down_rep_recv.initial_hdr.lct,
2075 mgr->down_rep_recv.initial_hdr.rad[0],
2076 mgr->down_rep_recv.msg[0]);
2077 drm_dp_put_mst_branch_device(mstb);
2078 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2079 return 0;
2080 }
2081
2082 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2083 if (txmsg->reply.reply_type == 1) {
2084 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);
2085 }
2086
2087 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2088 drm_dp_put_mst_branch_device(mstb);
2089
2090 mutex_lock(&mgr->qlock);
2091 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2092 mstb->tx_slots[slot] = NULL;
2093 mutex_unlock(&mgr->qlock);
2094
2095 wake_up(&mgr->tx_waitq);
2096 }
2097 return ret;
2098 }
2099
2100 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2101 {
2102 int ret = 0;
2103 drm_dp_get_one_sb_msg(mgr, true);
2104
2105 if (mgr->up_req_recv.have_eomt) {
2106 struct drm_dp_sideband_msg_req_body msg;
2107 struct drm_dp_mst_branch *mstb;
2108 bool seqno;
2109 mstb = drm_dp_get_mst_branch_device(mgr,
2110 mgr->up_req_recv.initial_hdr.lct,
2111 mgr->up_req_recv.initial_hdr.rad);
2112 if (!mstb) {
2113 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2114 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2115 return 0;
2116 }
2117
2118 seqno = mgr->up_req_recv.initial_hdr.seqno;
2119 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2120
2121 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2122 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2123 drm_dp_update_port(mstb, &msg.u.conn_stat);
2124 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);
2125 (*mgr->cbs->hotplug)(mgr);
2126
2127 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2128 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2129 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2130 }
2131
2132 drm_dp_put_mst_branch_device(mstb);
2133 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2134 }
2135 return ret;
2136 }
2137
2138 /**
2139 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2140 * @mgr: manager to notify irq for.
2141 * @esi: 4 bytes from SINK_COUNT_ESI
2142 * @handled: whether the hpd interrupt was consumed or not
2143 *
2144 * This should be called from the driver when it detects a short IRQ,
2145 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2146 * topology manager will process the sideband messages received as a result
2147 * of this.
2148 */
2149 int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2150 {
2151 int ret = 0;
2152 int sc;
2153 *handled = false;
2154 sc = esi[0] & 0x3f;
2155
2156 if (sc != mgr->sink_count) {
2157 mgr->sink_count = sc;
2158 *handled = true;
2159 }
2160
2161 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2162 ret = drm_dp_mst_handle_down_rep(mgr);
2163 *handled = true;
2164 }
2165
2166 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2167 ret |= drm_dp_mst_handle_up_req(mgr);
2168 *handled = true;
2169 }
2170
2171 drm_dp_mst_kick_tx(mgr);
2172 return ret;
2173 }
2174 EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2175
2176 /**
2177 * drm_dp_mst_detect_port() - get connection status for an MST port
2178 * @mgr: manager for this port
2179 * @port: unverified pointer to a port
2180 *
2181 * This returns the current connection state for a port. It validates the
2182 * port pointer still exists so the caller doesn't require a reference
2183 */
2184 enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector,
2185 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2186 {
2187 enum drm_connector_status status = connector_status_disconnected;
2188
2189 /* we need to search for the port in the mgr in case its gone */
2190 port = drm_dp_get_validated_port_ref(mgr, port);
2191 if (!port)
2192 return connector_status_disconnected;
2193
2194 if (!port->ddps)
2195 goto out;
2196
2197 switch (port->pdt) {
2198 case DP_PEER_DEVICE_NONE:
2199 case DP_PEER_DEVICE_MST_BRANCHING:
2200 break;
2201
2202 case DP_PEER_DEVICE_SST_SINK:
2203 status = connector_status_connected;
2204 /* for logical ports - cache the EDID */
2205 if (port->port_num >= 8 && !port->cached_edid) {
2206 port->cached_edid = drm_get_edid(connector, &port->aux.ddc);
2207 }
2208 break;
2209 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2210 if (port->ldps)
2211 status = connector_status_connected;
2212 break;
2213 }
2214 out:
2215 drm_dp_put_port(port);
2216 return status;
2217 }
2218 EXPORT_SYMBOL(drm_dp_mst_detect_port);
2219
2220 /**
2221 * drm_dp_mst_get_edid() - get EDID for an MST port
2222 * @connector: toplevel connector to get EDID for
2223 * @mgr: manager for this port
2224 * @port: unverified pointer to a port.
2225 *
2226 * This returns an EDID for the port connected to a connector,
2227 * It validates the pointer still exists so the caller doesn't require a
2228 * reference.
2229 */
2230 struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2231 {
2232 struct edid *edid = NULL;
2233
2234 /* we need to search for the port in the mgr in case its gone */
2235 port = drm_dp_get_validated_port_ref(mgr, port);
2236 if (!port)
2237 return NULL;
2238
2239 if (port->cached_edid)
2240 edid = drm_edid_duplicate(port->cached_edid);
2241 else
2242 edid = drm_get_edid(connector, &port->aux.ddc);
2243
2244 drm_mode_connector_set_tile_property(connector);
2245 drm_dp_put_port(port);
2246 return edid;
2247 }
2248 EXPORT_SYMBOL(drm_dp_mst_get_edid);
2249
2250 /**
2251 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2252 * @mgr: manager to use
2253 * @pbn: payload bandwidth to convert into slots.
2254 */
2255 int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2256 int pbn)
2257 {
2258 int num_slots;
2259
2260 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2261
2262 if (num_slots > mgr->avail_slots)
2263 return -ENOSPC;
2264 return num_slots;
2265 }
2266 EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2267
2268 static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2269 struct drm_dp_vcpi *vcpi, int pbn)
2270 {
2271 int num_slots;
2272 int ret;
2273
2274 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2275
2276 if (num_slots > mgr->avail_slots)
2277 return -ENOSPC;
2278
2279 vcpi->pbn = pbn;
2280 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2281 vcpi->num_slots = num_slots;
2282
2283 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2284 if (ret < 0)
2285 return ret;
2286 return 0;
2287 }
2288
2289 /**
2290 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2291 * @mgr: manager for this port
2292 * @port: port to allocate a virtual channel for.
2293 * @pbn: payload bandwidth number to request
2294 * @slots: returned number of slots for this PBN.
2295 */
2296 bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2297 {
2298 int ret;
2299
2300 port = drm_dp_get_validated_port_ref(mgr, port);
2301 if (!port)
2302 return false;
2303
2304 if (port->vcpi.vcpi > 0) {
2305 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2306 if (pbn == port->vcpi.pbn) {
2307 *slots = port->vcpi.num_slots;
2308 return true;
2309 }
2310 }
2311
2312 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2313 if (ret) {
2314 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2315 goto out;
2316 }
2317 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2318 *slots = port->vcpi.num_slots;
2319
2320 drm_dp_put_port(port);
2321 return true;
2322 out:
2323 return false;
2324 }
2325 EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2326
2327 /**
2328 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2329 * @mgr: manager for this port
2330 * @port: unverified pointer to a port.
2331 *
2332 * This just resets the number of slots for the ports VCPI for later programming.
2333 */
2334 void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2335 {
2336 port = drm_dp_get_validated_port_ref(mgr, port);
2337 if (!port)
2338 return;
2339 port->vcpi.num_slots = 0;
2340 drm_dp_put_port(port);
2341 }
2342 EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2343
2344 /**
2345 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2346 * @mgr: manager for this port
2347 * @port: unverified port to deallocate vcpi for
2348 */
2349 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2350 {
2351 port = drm_dp_get_validated_port_ref(mgr, port);
2352 if (!port)
2353 return;
2354
2355 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2356 port->vcpi.num_slots = 0;
2357 port->vcpi.pbn = 0;
2358 port->vcpi.aligned_pbn = 0;
2359 port->vcpi.vcpi = 0;
2360 drm_dp_put_port(port);
2361 }
2362 EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2363
2364 static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2365 int id, struct drm_dp_payload *payload)
2366 {
2367 u8 payload_alloc[3], status;
2368 int ret;
2369 int retries = 0;
2370
2371 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2372 DP_PAYLOAD_TABLE_UPDATED);
2373
2374 payload_alloc[0] = id;
2375 payload_alloc[1] = payload->start_slot;
2376 payload_alloc[2] = payload->num_slots;
2377
2378 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2379 if (ret != 3) {
2380 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2381 goto fail;
2382 }
2383
2384 retry:
2385 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2386 if (ret < 0) {
2387 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2388 goto fail;
2389 }
2390
2391 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2392 retries++;
2393 if (retries < 20) {
2394 usleep_range(10000, 20000);
2395 goto retry;
2396 }
2397 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2398 ret = -EINVAL;
2399 goto fail;
2400 }
2401 ret = 0;
2402 fail:
2403 return ret;
2404 }
2405
2406
2407 /**
2408 * drm_dp_check_act_status() - Check ACT handled status.
2409 * @mgr: manager to use
2410 *
2411 * Check the payload status bits in the DPCD for ACT handled completion.
2412 */
2413 int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2414 {
2415 u8 status;
2416 int ret;
2417 int count = 0;
2418
2419 do {
2420 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2421
2422 if (ret < 0) {
2423 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2424 goto fail;
2425 }
2426
2427 if (status & DP_PAYLOAD_ACT_HANDLED)
2428 break;
2429 count++;
2430 udelay(100);
2431
2432 } while (count < 30);
2433
2434 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2435 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2436 ret = -EINVAL;
2437 goto fail;
2438 }
2439 return 0;
2440 fail:
2441 return ret;
2442 }
2443 EXPORT_SYMBOL(drm_dp_check_act_status);
2444
2445 /**
2446 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2447 * @clock: dot clock for the mode
2448 * @bpp: bpp for the mode.
2449 *
2450 * This uses the formula in the spec to calculate the PBN value for a mode.
2451 */
2452 int drm_dp_calc_pbn_mode(int clock, int bpp)
2453 {
2454 fixed20_12 pix_bw;
2455 fixed20_12 fbpp;
2456 fixed20_12 result;
2457 fixed20_12 margin, tmp;
2458 u32 res;
2459
2460 pix_bw.full = dfixed_const(clock);
2461 fbpp.full = dfixed_const(bpp);
2462 tmp.full = dfixed_const(8);
2463 fbpp.full = dfixed_div(fbpp, tmp);
2464
2465 result.full = dfixed_mul(pix_bw, fbpp);
2466 margin.full = dfixed_const(54);
2467 tmp.full = dfixed_const(64);
2468 margin.full = dfixed_div(margin, tmp);
2469 result.full = dfixed_div(result, margin);
2470
2471 margin.full = dfixed_const(1006);
2472 tmp.full = dfixed_const(1000);
2473 margin.full = dfixed_div(margin, tmp);
2474 result.full = dfixed_mul(result, margin);
2475
2476 result.full = dfixed_div(result, tmp);
2477 result.full = dfixed_ceil(result);
2478 res = dfixed_trunc(result);
2479 return res;
2480 }
2481 EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2482
2483 static int test_calc_pbn_mode(void)
2484 {
2485 int ret;
2486 ret = drm_dp_calc_pbn_mode(154000, 30);
2487 if (ret != 689)
2488 return -EINVAL;
2489 ret = drm_dp_calc_pbn_mode(234000, 30);
2490 if (ret != 1047)
2491 return -EINVAL;
2492 return 0;
2493 }
2494
2495 /* we want to kick the TX after we've ack the up/down IRQs. */
2496 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2497 {
2498 queue_work(system_long_wq, &mgr->tx_work);
2499 }
2500
2501 static void drm_dp_mst_dump_mstb(struct seq_file *m,
2502 struct drm_dp_mst_branch *mstb)
2503 {
2504 struct drm_dp_mst_port *port;
2505 int tabs = mstb->lct;
2506 char prefix[10];
2507 int i;
2508
2509 for (i = 0; i < tabs; i++)
2510 prefix[i] = '\t';
2511 prefix[i] = '\0';
2512
2513 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2514 list_for_each_entry(port, &mstb->ports, next) {
2515 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2516 if (port->mstb)
2517 drm_dp_mst_dump_mstb(m, port->mstb);
2518 }
2519 }
2520
2521 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2522 char *buf)
2523 {
2524 int ret;
2525 int i;
2526 for (i = 0; i < 4; i++) {
2527 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2528 if (ret != 16)
2529 break;
2530 }
2531 if (i == 4)
2532 return true;
2533 return false;
2534 }
2535
2536 /**
2537 * drm_dp_mst_dump_topology(): dump topology to seq file.
2538 * @m: seq_file to dump output to
2539 * @mgr: manager to dump current topology for.
2540 *
2541 * helper to dump MST topology to a seq file for debugfs.
2542 */
2543 void drm_dp_mst_dump_topology(struct seq_file *m,
2544 struct drm_dp_mst_topology_mgr *mgr)
2545 {
2546 int i;
2547 struct drm_dp_mst_port *port;
2548 mutex_lock(&mgr->lock);
2549 if (mgr->mst_primary)
2550 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2551
2552 /* dump VCPIs */
2553 mutex_unlock(&mgr->lock);
2554
2555 mutex_lock(&mgr->payload_lock);
2556 seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask);
2557
2558 for (i = 0; i < mgr->max_payloads; i++) {
2559 if (mgr->proposed_vcpis[i]) {
2560 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2561 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2562 } else
2563 seq_printf(m, "vcpi %d:unsed\n", i);
2564 }
2565 for (i = 0; i < mgr->max_payloads; i++) {
2566 seq_printf(m, "payload %d: %d, %d, %d\n",
2567 i,
2568 mgr->payloads[i].payload_state,
2569 mgr->payloads[i].start_slot,
2570 mgr->payloads[i].num_slots);
2571
2572
2573 }
2574 mutex_unlock(&mgr->payload_lock);
2575
2576 mutex_lock(&mgr->lock);
2577 if (mgr->mst_primary) {
2578 u8 buf[64];
2579 bool bret;
2580 int ret;
2581 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2582 seq_printf(m, "dpcd: ");
2583 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2584 seq_printf(m, "%02x ", buf[i]);
2585 seq_printf(m, "\n");
2586 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2587 seq_printf(m, "faux/mst: ");
2588 for (i = 0; i < 2; i++)
2589 seq_printf(m, "%02x ", buf[i]);
2590 seq_printf(m, "\n");
2591 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2592 seq_printf(m, "mst ctrl: ");
2593 for (i = 0; i < 1; i++)
2594 seq_printf(m, "%02x ", buf[i]);
2595 seq_printf(m, "\n");
2596
2597 bret = dump_dp_payload_table(mgr, buf);
2598 if (bret == true) {
2599 seq_printf(m, "payload table: ");
2600 for (i = 0; i < 63; i++)
2601 seq_printf(m, "%02x ", buf[i]);
2602 seq_printf(m, "\n");
2603 }
2604
2605 }
2606
2607 mutex_unlock(&mgr->lock);
2608
2609 }
2610 EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2611
2612 static void drm_dp_tx_work(struct work_struct *work)
2613 {
2614 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2615
2616 mutex_lock(&mgr->qlock);
2617 if (mgr->tx_down_in_progress)
2618 process_single_down_tx_qlock(mgr);
2619 mutex_unlock(&mgr->qlock);
2620 }
2621
2622 /**
2623 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2624 * @mgr: manager struct to initialise
2625 * @dev: device providing this structure - for i2c addition.
2626 * @aux: DP helper aux channel to talk to this device
2627 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2628 * @max_payloads: maximum number of payloads this GPU can source
2629 * @conn_base_id: the connector object ID the MST device is connected to.
2630 *
2631 * Return 0 for success, or negative error code on failure
2632 */
2633 int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2634 struct device *dev, struct drm_dp_aux *aux,
2635 int max_dpcd_transaction_bytes,
2636 int max_payloads, int conn_base_id)
2637 {
2638 mutex_init(&mgr->lock);
2639 mutex_init(&mgr->qlock);
2640 mutex_init(&mgr->payload_lock);
2641 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2642 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2643 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2644 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2645 init_waitqueue_head(&mgr->tx_waitq);
2646 mgr->dev = dev;
2647 mgr->aux = aux;
2648 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2649 mgr->max_payloads = max_payloads;
2650 mgr->conn_base_id = conn_base_id;
2651 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2652 if (!mgr->payloads)
2653 return -ENOMEM;
2654 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2655 if (!mgr->proposed_vcpis)
2656 return -ENOMEM;
2657 set_bit(0, &mgr->payload_mask);
2658 test_calc_pbn_mode();
2659 return 0;
2660 }
2661 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2662
2663 /**
2664 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2665 * @mgr: manager to destroy
2666 */
2667 void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2668 {
2669 mutex_lock(&mgr->payload_lock);
2670 kfree(mgr->payloads);
2671 mgr->payloads = NULL;
2672 kfree(mgr->proposed_vcpis);
2673 mgr->proposed_vcpis = NULL;
2674 mutex_unlock(&mgr->payload_lock);
2675 mgr->dev = NULL;
2676 mgr->aux = NULL;
2677 }
2678 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2679
2680 /* I2C device */
2681 static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2682 int num)
2683 {
2684 struct drm_dp_aux *aux = adapter->algo_data;
2685 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2686 struct drm_dp_mst_branch *mstb;
2687 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2688 unsigned int i;
2689 bool reading = false;
2690 struct drm_dp_sideband_msg_req_body msg;
2691 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2692 int ret;
2693
2694 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2695 if (!mstb)
2696 return -EREMOTEIO;
2697
2698 /* construct i2c msg */
2699 /* see if last msg is a read */
2700 if (msgs[num - 1].flags & I2C_M_RD)
2701 reading = true;
2702
2703 if (!reading) {
2704 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2705 ret = -EIO;
2706 goto out;
2707 }
2708
2709 msg.req_type = DP_REMOTE_I2C_READ;
2710 msg.u.i2c_read.num_transactions = num - 1;
2711 msg.u.i2c_read.port_number = port->port_num;
2712 for (i = 0; i < num - 1; i++) {
2713 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2714 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2715 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2716 }
2717 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2718 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2719
2720 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2721 if (!txmsg) {
2722 ret = -ENOMEM;
2723 goto out;
2724 }
2725
2726 txmsg->dst = mstb;
2727 drm_dp_encode_sideband_req(&msg, txmsg);
2728
2729 drm_dp_queue_down_tx(mgr, txmsg);
2730
2731 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2732 if (ret > 0) {
2733
2734 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2735 ret = -EREMOTEIO;
2736 goto out;
2737 }
2738 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2739 ret = -EIO;
2740 goto out;
2741 }
2742 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2743 ret = num;
2744 }
2745 out:
2746 kfree(txmsg);
2747 drm_dp_put_mst_branch_device(mstb);
2748 return ret;
2749 }
2750
2751 static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2752 {
2753 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2754 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2755 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2756 I2C_FUNC_10BIT_ADDR;
2757 }
2758
2759 static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2760 .functionality = drm_dp_mst_i2c_functionality,
2761 .master_xfer = drm_dp_mst_i2c_xfer,
2762 };
2763
2764 /**
2765 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2766 * @aux: DisplayPort AUX channel
2767 *
2768 * Returns 0 on success or a negative error code on failure.
2769 */
2770 static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2771 {
2772 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2773 aux->ddc.algo_data = aux;
2774 aux->ddc.retries = 3;
2775
2776 aux->ddc.class = I2C_CLASS_DDC;
2777 aux->ddc.owner = THIS_MODULE;
2778 aux->ddc.dev.parent = aux->dev;
2779 aux->ddc.dev.of_node = aux->dev->of_node;
2780
2781 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2782 sizeof(aux->ddc.name));
2783
2784 return i2c_add_adapter(&aux->ddc);
2785 }
2786
2787 /**
2788 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2789 * @aux: DisplayPort AUX channel
2790 */
2791 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2792 {
2793 i2c_del_adapter(&aux->ddc);
2794 }
Linux with added FPC-III support