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drm/atomic: rip out unnecessary locking checks
[mirror_ubuntu-artful-kernel.git] / drivers / gpu / drm / drm_dp_mst_topology.c
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ad7f8a1f
DA		 1/*
2 * Copyright © 2014 Red Hat
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#include <linux/kernel.h>
24#include <linux/delay.h>
25#include <linux/init.h>
26#include <linux/errno.h>
27#include <linux/sched.h>
75bc08ab 28#include <linux/seq_file.h>
ad7f8a1f
DA		 29#include <linux/i2c.h>
30#include <drm/drm_dp_mst_helper.h>
31#include <drm/drmP.h>
32
33#include <drm/drm_fixed.h>
34
35/**
36 * DOC: dp mst helper
37 *
38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
39 * protocol. The helpers contain a topology manager and bandwidth manager.
40 * The helpers encapsulate the sending and received of sideband msgs.
41 */
42static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
43 char *buf);
44static int test_calc_pbn_mode(void);
45
46static void drm_dp_put_port(struct drm_dp_mst_port *port);
47
48static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
49 int id,
50 struct drm_dp_payload *payload);
51
52static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
53 struct drm_dp_mst_port *port,
54 int offset, int size, u8 *bytes);
55
56static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
57 struct drm_dp_mst_branch *mstb);
58static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
59 struct drm_dp_mst_branch *mstb,
60 struct drm_dp_mst_port *port);
61static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
62 u8 *guid);
63
64static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
65static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
66static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
67/* sideband msg handling */
68static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
69{
70 u8 bitmask = 0x80;
71 u8 bitshift = 7;
72 u8 array_index = 0;
73 int number_of_bits = num_nibbles * 4;
74 u8 remainder = 0;
75
76 while (number_of_bits != 0) {
77 number_of_bits--;
78 remainder <<= 1;
79 remainder |= (data[array_index] & bitmask) >> bitshift;
80 bitmask >>= 1;
81 bitshift--;
82 if (bitmask == 0) {
83 bitmask = 0x80;
84 bitshift = 7;
85 array_index++;
86 }
87 if ((remainder & 0x10) == 0x10)
88 remainder ^= 0x13;
89 }
90
91 number_of_bits = 4;
92 while (number_of_bits != 0) {
93 number_of_bits--;
94 remainder <<= 1;
95 if ((remainder & 0x10) != 0)
96 remainder ^= 0x13;
97 }
98
99 return remainder;
100}
101
102static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
103{
104 u8 bitmask = 0x80;
105 u8 bitshift = 7;
106 u8 array_index = 0;
107 int number_of_bits = number_of_bytes * 8;
108 u16 remainder = 0;
109
110 while (number_of_bits != 0) {
111 number_of_bits--;
112 remainder <<= 1;
113 remainder |= (data[array_index] & bitmask) >> bitshift;
114 bitmask >>= 1;
115 bitshift--;
116 if (bitmask == 0) {
117 bitmask = 0x80;
118 bitshift = 7;
119 array_index++;
120 }
121 if ((remainder & 0x100) == 0x100)
122 remainder ^= 0xd5;
123 }
124
125 number_of_bits = 8;
126 while (number_of_bits != 0) {
127 number_of_bits--;
128 remainder <<= 1;
129 if ((remainder & 0x100) != 0)
130 remainder ^= 0xd5;
131 }
132
133 return remainder & 0xff;
134}
135static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
136{
137 u8 size = 3;
138 size += (hdr->lct / 2);
139 return size;
140}
141
142static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
143 u8 *buf, int *len)
144{
145 int idx = 0;
146 int i;
147 u8 crc4;
148 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
149 for (i = 0; i < (hdr->lct / 2); i++)
150 buf[idx++] = hdr->rad[i];
151 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
152 (hdr->msg_len & 0x3f);
153 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
154
155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
156 buf[idx - 1] |= (crc4 & 0xf);
157
158 *len = idx;
159}
160
161static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
162 u8 *buf, int buflen, u8 *hdrlen)
163{
164 u8 crc4;
165 u8 len;
166 int i;
167 u8 idx;
168 if (buf[0] == 0)
169 return false;
170 len = 3;
171 len += ((buf[0] & 0xf0) >> 4) / 2;
172 if (len > buflen)
173 return false;
174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
175
176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
178 return false;
179 }
180
181 hdr->lct = (buf[0] & 0xf0) >> 4;
182 hdr->lcr = (buf[0] & 0xf);
183 idx = 1;
184 for (i = 0; i < (hdr->lct / 2); i++)
185 hdr->rad[i] = buf[idx++];
186 hdr->broadcast = (buf[idx] >> 7) & 0x1;
187 hdr->path_msg = (buf[idx] >> 6) & 0x1;
188 hdr->msg_len = buf[idx] & 0x3f;
189 idx++;
190 hdr->somt = (buf[idx] >> 7) & 0x1;
191 hdr->eomt = (buf[idx] >> 6) & 0x1;
192 hdr->seqno = (buf[idx] >> 4) & 0x1;
193 idx++;
194 *hdrlen = idx;
195 return true;
196}
197
198static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
199 struct drm_dp_sideband_msg_tx *raw)
200{
201 int idx = 0;
202 int i;
203 u8 *buf = raw->msg;
204 buf[idx++] = req->req_type & 0x7f;
205
206 switch (req->req_type) {
207 case DP_ENUM_PATH_RESOURCES:
208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
209 idx++;
210 break;
211 case DP_ALLOCATE_PAYLOAD:
212 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
213 (req->u.allocate_payload.number_sdp_streams & 0xf);
214 idx++;
215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
216 idx++;
217 buf[idx] = (req->u.allocate_payload.pbn >> 8);
218 idx++;
219 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
220 idx++;
221 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
222 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
223 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
224 idx++;
225 }
226 if (req->u.allocate_payload.number_sdp_streams & 1) {
227 i = req->u.allocate_payload.number_sdp_streams - 1;
228 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
229 idx++;
230 }
231 break;
232 case DP_QUERY_PAYLOAD:
233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
234 idx++;
235 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
236 idx++;
237 break;
238 case DP_REMOTE_DPCD_READ:
239 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
240 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
241 idx++;
242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
243 idx++;
244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
245 idx++;
246 buf[idx] = (req->u.dpcd_read.num_bytes);
247 idx++;
248 break;
249
250 case DP_REMOTE_DPCD_WRITE:
251 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
252 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
253 idx++;
254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
255 idx++;
256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
257 idx++;
258 buf[idx] = (req->u.dpcd_write.num_bytes);
259 idx++;
260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
261 idx += req->u.dpcd_write.num_bytes;
262 break;
263 case DP_REMOTE_I2C_READ:
264 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
265 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
266 idx++;
267 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
268 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
269 idx++;
270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
271 idx++;
272 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
273 idx += req->u.i2c_read.transactions[i].num_bytes;
274
275 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
276 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
277 idx++;
278 }
279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
280 idx++;
281 buf[idx] = (req->u.i2c_read.num_bytes_read);
282 idx++;
283 break;
284
285 case DP_REMOTE_I2C_WRITE:
286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
287 idx++;
288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
289 idx++;
290 buf[idx] = (req->u.i2c_write.num_bytes);
291 idx++;
292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
293 idx += req->u.i2c_write.num_bytes;
294 break;
295 }
296 raw->cur_len = idx;
297}
298
299static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
300{
301 u8 crc4;
302 crc4 = drm_dp_msg_data_crc4(msg, len);
303 msg[len] = crc4;
304}
305
306static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
307 struct drm_dp_sideband_msg_tx *raw)
308{
309 int idx = 0;
310 u8 *buf = raw->msg;
311
312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
313
314 raw->cur_len = idx;
315}
316
317/* this adds a chunk of msg to the builder to get the final msg */
318static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
319 u8 *replybuf, u8 replybuflen, bool hdr)
320{
321 int ret;
322 u8 crc4;
323
324 if (hdr) {
325 u8 hdrlen;
326 struct drm_dp_sideband_msg_hdr recv_hdr;
327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
328 if (ret == false) {
329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
330 return false;
331 }
332
333 /* get length contained in this portion */
334 msg->curchunk_len = recv_hdr.msg_len;
335 msg->curchunk_hdrlen = hdrlen;
336
337 /* we have already gotten an somt - don't bother parsing */
338 if (recv_hdr.somt && msg->have_somt)
339 return false;
340
341 if (recv_hdr.somt) {
342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
343 msg->have_somt = true;
344 }
345 if (recv_hdr.eomt)
346 msg->have_eomt = true;
347
348 /* copy the bytes for the remainder of this header chunk */
349 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
350 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
351 } else {
352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
353 msg->curchunk_idx += replybuflen;
354 }
355
356 if (msg->curchunk_idx >= msg->curchunk_len) {
357 /* do CRC */
358 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
359 /* copy chunk into bigger msg */
360 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
361 msg->curlen += msg->curchunk_len - 1;
362 }
363 return true;
364}
365
366static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
367 struct drm_dp_sideband_msg_reply_body *repmsg)
368{
369 int idx = 1;
370 int i;
371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
372 idx += 16;
373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
374 idx++;
375 if (idx > raw->curlen)
376 goto fail_len;
377 for (i = 0; i < repmsg->u.link_addr.nports; i++) {
378 if (raw->msg[idx] & 0x80)
379 repmsg->u.link_addr.ports[i].input_port = 1;
380
381 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
382 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
383
384 idx++;
385 if (idx > raw->curlen)
386 goto fail_len;
387 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
388 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
389 if (repmsg->u.link_addr.ports[i].input_port == 0)
390 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
391 idx++;
392 if (idx > raw->curlen)
393 goto fail_len;
394 if (repmsg->u.link_addr.ports[i].input_port == 0) {
395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
396 idx++;
397 if (idx > raw->curlen)
398 goto fail_len;
399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
400 idx += 16;
401 if (idx > raw->curlen)
402 goto fail_len;
403 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
404 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
405 idx++;
406
407 }
408 if (idx > raw->curlen)
409 goto fail_len;
410 }
411
412 return true;
413fail_len:
414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
415 return false;
416}
417
418static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
419 struct drm_dp_sideband_msg_reply_body *repmsg)
420{
421 int idx = 1;
422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
423 idx++;
424 if (idx > raw->curlen)
425 goto fail_len;
426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
427 if (idx > raw->curlen)
428 goto fail_len;
429
430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
431 return true;
432fail_len:
433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
434 return false;
435}
436
437static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
438 struct drm_dp_sideband_msg_reply_body *repmsg)
439{
440 int idx = 1;
441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
442 idx++;
443 if (idx > raw->curlen)
444 goto fail_len;
445 return true;
446fail_len:
447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
448 return false;
449}
450
451static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
452 struct drm_dp_sideband_msg_reply_body *repmsg)
453{
454 int idx = 1;
455
456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
457 idx++;
458 if (idx > raw->curlen)
459 goto fail_len;
460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
461 idx++;
462 /* TODO check */
463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
464 return true;
465fail_len:
466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
467 return false;
468}
469
470static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
471 struct drm_dp_sideband_msg_reply_body *repmsg)
472{
473 int idx = 1;
474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
475 idx++;
476 if (idx > raw->curlen)
477 goto fail_len;
478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
479 idx += 2;
480 if (idx > raw->curlen)
481 goto fail_len;
482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
483 idx += 2;
484 if (idx > raw->curlen)
485 goto fail_len;
486 return true;
487fail_len:
488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
489 return false;
490}
491
492static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
493 struct drm_dp_sideband_msg_reply_body *repmsg)
494{
495 int idx = 1;
496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
497 idx++;
498 if (idx > raw->curlen)
499 goto fail_len;
500 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
501 idx++;
502 if (idx > raw->curlen)
503 goto fail_len;
504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
505 idx += 2;
506 if (idx > raw->curlen)
507 goto fail_len;
508 return true;
509fail_len:
510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
511 return false;
512}
513
514static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
515 struct drm_dp_sideband_msg_reply_body *repmsg)
516{
517 int idx = 1;
518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
519 idx++;
520 if (idx > raw->curlen)
521 goto fail_len;
522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
523 idx += 2;
524 if (idx > raw->curlen)
525 goto fail_len;
526 return true;
527fail_len:
528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
529 return false;
530}
531
532static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
533 struct drm_dp_sideband_msg_reply_body *msg)
534{
535 memset(msg, 0, sizeof(*msg));
536 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
537 msg->req_type = (raw->msg[0] & 0x7f);
538
539 if (msg->reply_type) {
540 memcpy(msg->u.nak.guid, &raw->msg[1], 16);
541 msg->u.nak.reason = raw->msg[17];
542 msg->u.nak.nak_data = raw->msg[18];
543 return false;
544 }
545
546 switch (msg->req_type) {
547 case DP_LINK_ADDRESS:
548 return drm_dp_sideband_parse_link_address(raw, msg);
549 case DP_QUERY_PAYLOAD:
550 return drm_dp_sideband_parse_query_payload_ack(raw, msg);
551 case DP_REMOTE_DPCD_READ:
552 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
553 case DP_REMOTE_DPCD_WRITE:
554 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
555 case DP_REMOTE_I2C_READ:
556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
557 case DP_ENUM_PATH_RESOURCES:
558 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
559 case DP_ALLOCATE_PAYLOAD:
560 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
561 default:
562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
563 return false;
564 }
565}
566
567static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
568 struct drm_dp_sideband_msg_req_body *msg)
569{
570 int idx = 1;
571
572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
573 idx++;
574 if (idx > raw->curlen)
575 goto fail_len;
576
577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
578 idx += 16;
579 if (idx > raw->curlen)
580 goto fail_len;
581
582 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
583 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
584 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
585 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
586 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
587 idx++;
588 return true;
589fail_len:
590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
591 return false;
592}
593
594static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
595 struct drm_dp_sideband_msg_req_body *msg)
596{
597 int idx = 1;
598
599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
600 idx++;
601 if (idx > raw->curlen)
602 goto fail_len;
603
604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
605 idx += 16;
606 if (idx > raw->curlen)
607 goto fail_len;
608
609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
610 idx++;
611 return true;
612fail_len:
613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
614 return false;
615}
616
617static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
618 struct drm_dp_sideband_msg_req_body *msg)
619{
620 memset(msg, 0, sizeof(*msg));
621 msg->req_type = (raw->msg[0] & 0x7f);
622
623 switch (msg->req_type) {
624 case DP_CONNECTION_STATUS_NOTIFY:
625 return drm_dp_sideband_parse_connection_status_notify(raw, msg);
626 case DP_RESOURCE_STATUS_NOTIFY:
627 return drm_dp_sideband_parse_resource_status_notify(raw, msg);
628 default:
629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
630 return false;
631 }
632}
633
634static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
635{
636 struct drm_dp_sideband_msg_req_body req;
637
638 req.req_type = DP_REMOTE_DPCD_WRITE;
639 req.u.dpcd_write.port_number = port_num;
640 req.u.dpcd_write.dpcd_address = offset;
641 req.u.dpcd_write.num_bytes = num_bytes;
642 req.u.dpcd_write.bytes = bytes;
643 drm_dp_encode_sideband_req(&req, msg);
644
645 return 0;
646}
647
648static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
649{
650 struct drm_dp_sideband_msg_req_body req;
651
652 req.req_type = DP_LINK_ADDRESS;
653 drm_dp_encode_sideband_req(&req, msg);
654 return 0;
655}
656
657static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
658{
659 struct drm_dp_sideband_msg_req_body req;
660
661 req.req_type = DP_ENUM_PATH_RESOURCES;
662 req.u.port_num.port_number = port_num;
663 drm_dp_encode_sideband_req(&req, msg);
664 msg->path_msg = true;
665 return 0;
666}
667
668static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
669 u8 vcpi, uint16_t pbn)
670{
671 struct drm_dp_sideband_msg_req_body req;
672 memset(&req, 0, sizeof(req));
673 req.req_type = DP_ALLOCATE_PAYLOAD;
674 req.u.allocate_payload.port_number = port_num;
675 req.u.allocate_payload.vcpi = vcpi;
676 req.u.allocate_payload.pbn = pbn;
677 drm_dp_encode_sideband_req(&req, msg);
678 msg->path_msg = true;
679 return 0;
680}
681
682static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
683 struct drm_dp_vcpi *vcpi)
684{
dfda0df3 685 int ret, vcpi_ret;
ad7f8a1f
DA		 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
dfda0df3
DA		 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
ad7f8a1f 702 set_bit(ret, &mgr->payload_mask);
dfda0df3
DA		 703 set_bit(vcpi_ret, &mgr->vcpi_mask);
704 vcpi->vcpi = vcpi_ret + 1;
ad7f8a1f
DA		 705 mgr->proposed_vcpis[ret - 1] = vcpi;
706out_unlock:
707 mutex_unlock(&mgr->payload_lock);
708 return ret;
709}
710
711static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
dfda0df3 712 int vcpi)
ad7f8a1f 713{
dfda0df3
DA		 714 int i;
715 if (vcpi == 0)
ad7f8a1f
DA		 716 return;
717
718 mutex_lock(&mgr->payload_lock);
dfda0df3
DA		 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 }
ad7f8a1f
DA		 729 mutex_unlock(&mgr->payload_lock);
730}
731
732static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
733 struct drm_dp_sideband_msg_tx *txmsg)
734{
735 bool ret;
736 mutex_lock(&mgr->qlock);
737 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
738 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
739 mutex_unlock(&mgr->qlock);
740 return ret;
741}
742
743static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
744 struct drm_dp_sideband_msg_tx *txmsg)
745{
746 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
747 int ret;
748
749 ret = wait_event_timeout(mgr->tx_waitq,
750 check_txmsg_state(mgr, txmsg),
751 (4 * HZ));
752 mutex_lock(&mstb->mgr->qlock);
753 if (ret > 0) {
754 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
755 ret = -EIO;
756 goto out;
757 }
758 } else {
759 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
760
761 /* dump some state */
762 ret = -EIO;
763
764 /* remove from q */
765 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
766 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
767 list_del(&txmsg->next);
768 }
769
770 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
771 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
772 mstb->tx_slots[txmsg->seqno] = NULL;
773 }
774 }
775out:
776 mutex_unlock(&mgr->qlock);
777
778 return ret;
779}
780
781static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
782{
783 struct drm_dp_mst_branch *mstb;
784
785 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
786 if (!mstb)
787 return NULL;
788
789 mstb->lct = lct;
790 if (lct > 1)
791 memcpy(mstb->rad, rad, lct / 2);
792 INIT_LIST_HEAD(&mstb->ports);
793 kref_init(&mstb->kref);
794 return mstb;
795}
796
797static void drm_dp_destroy_mst_branch_device(struct kref *kref)
798{
799 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
800 struct drm_dp_mst_port *port, *tmp;
801 bool wake_tx = false;
802
803 cancel_work_sync(&mstb->mgr->work);
804
805 /*
806 * destroy all ports - don't need lock
807 * as there are no more references to the mst branch
808 * device at this point.
809 */
810 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
811 list_del(&port->next);
812 drm_dp_put_port(port);
813 }
814
815 /* drop any tx slots msg */
816 mutex_lock(&mstb->mgr->qlock);
817 if (mstb->tx_slots[0]) {
818 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
819 mstb->tx_slots[0] = NULL;
820 wake_tx = true;
821 }
822 if (mstb->tx_slots[1]) {
823 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
824 mstb->tx_slots[1] = NULL;
825 wake_tx = true;
826 }
827 mutex_unlock(&mstb->mgr->qlock);
828
829 if (wake_tx)
830 wake_up(&mstb->mgr->tx_waitq);
831 kfree(mstb);
832}
833
834static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
835{
836 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
837}
838
839
840static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
841{
842 switch (old_pdt) {
843 case DP_PEER_DEVICE_DP_LEGACY_CONV:
844 case DP_PEER_DEVICE_SST_SINK:
845 /* remove i2c over sideband */
846 drm_dp_mst_unregister_i2c_bus(&port->aux);
847 break;
848 case DP_PEER_DEVICE_MST_BRANCHING:
849 drm_dp_put_mst_branch_device(port->mstb);
850 port->mstb = NULL;
851 break;
852 }
853}
854
855static void drm_dp_destroy_port(struct kref *kref)
856{
857 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
858 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
859 if (!port->input) {
860 port->vcpi.num_slots = 0;
861 if (port->connector)
862 (*port->mgr->cbs->destroy_connector)(mgr, port->connector);
863 drm_dp_port_teardown_pdt(port, port->pdt);
864
865 if (!port->input && port->vcpi.vcpi > 0)
866 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
867 }
868 kfree(port);
869
870 (*mgr->cbs->hotplug)(mgr);
871}
872
873static void drm_dp_put_port(struct drm_dp_mst_port *port)
874{
875 kref_put(&port->kref, drm_dp_destroy_port);
876}
877
878static 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)
879{
880 struct drm_dp_mst_port *port;
881 struct drm_dp_mst_branch *rmstb;
882 if (to_find == mstb) {
883 kref_get(&mstb->kref);
884 return mstb;
885 }
886 list_for_each_entry(port, &mstb->ports, next) {
887 if (port->mstb) {
888 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
889 if (rmstb)
890 return rmstb;
891 }
892 }
893 return NULL;
894}
895
896static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb)
897{
898 struct drm_dp_mst_branch *rmstb = NULL;
899 mutex_lock(&mgr->lock);
900 if (mgr->mst_primary)
901 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
902 mutex_unlock(&mgr->lock);
903 return rmstb;
904}
905
906static 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)
907{
908 struct drm_dp_mst_port *port, *mport;
909
910 list_for_each_entry(port, &mstb->ports, next) {
911 if (port == to_find) {
912 kref_get(&port->kref);
913 return port;
914 }
915 if (port->mstb) {
916 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
917 if (mport)
918 return mport;
919 }
920 }
921 return NULL;
922}
923
924static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
925{
926 struct drm_dp_mst_port *rport = NULL;
927 mutex_lock(&mgr->lock);
928 if (mgr->mst_primary)
929 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
930 mutex_unlock(&mgr->lock);
931 return rport;
932}
933
934static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
935{
936 struct drm_dp_mst_port *port;
937
938 list_for_each_entry(port, &mstb->ports, next) {
939 if (port->port_num == port_num) {
940 kref_get(&port->kref);
941 return port;
942 }
943 }
944
945 return NULL;
946}
947
948/*
949 * calculate a new RAD for this MST branch device
950 * if parent has an LCT of 2 then it has 1 nibble of RAD,
951 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
952 */
953static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
954 u8 *rad)
955{
956 int lct = port->parent->lct;
957 int shift = 4;
958 int idx = lct / 2;
959 if (lct > 1) {
960 memcpy(rad, port->parent->rad, idx);
961 shift = (lct % 2) ? 4 : 0;
962 } else
963 rad[0] = 0;
964
965 rad[idx] |= port->port_num << shift;
966 return lct + 1;
967}
968
969/*
970 * return sends link address for new mstb
971 */
972static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
973{
974 int ret;
975 u8 rad[6], lct;
976 bool send_link = false;
977 switch (port->pdt) {
978 case DP_PEER_DEVICE_DP_LEGACY_CONV:
979 case DP_PEER_DEVICE_SST_SINK:
980 /* add i2c over sideband */
981 ret = drm_dp_mst_register_i2c_bus(&port->aux);
982 break;
983 case DP_PEER_DEVICE_MST_BRANCHING:
984 lct = drm_dp_calculate_rad(port, rad);
985
986 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
987 port->mstb->mgr = port->mgr;
988 port->mstb->port_parent = port;
989
990 send_link = true;
991 break;
992 }
993 return send_link;
994}
995
996static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
997 struct drm_dp_mst_port *port)
998{
999 int ret;
1000 if (port->dpcd_rev >= 0x12) {
1001 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
1002 if (!port->guid_valid) {
1003 ret = drm_dp_send_dpcd_write(mstb->mgr,
1004 port,
1005 DP_GUID,
1006 16, port->guid);
1007 port->guid_valid = true;
1008 }
1009 }
1010}
1011
1012static void build_mst_prop_path(struct drm_dp_mst_port *port,
1013 struct drm_dp_mst_branch *mstb,
d87af4d1
RS		 1014 char *proppath,
1015 size_t proppath_size)
ad7f8a1f
DA		 1016{
1017 int i;
1018 char temp[8];
d87af4d1 1019 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id);
ad7f8a1f
DA		 1020 for (i = 0; i < (mstb->lct - 1); i++) {
1021 int shift = (i % 2) ? 0 : 4;
1022 int port_num = mstb->rad[i / 2] >> shift;
d87af4d1
RS		 1023 snprintf(temp, sizeof(temp), "-%d", port_num);
1024 strlcat(proppath, temp, proppath_size);
ad7f8a1f 1025 }
d87af4d1
RS		 1026 snprintf(temp, sizeof(temp), "-%d", port->port_num);
1027 strlcat(proppath, temp, proppath_size);
ad7f8a1f
DA		 1028}
1029
1030static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1031 struct device *dev,
1032 struct drm_dp_link_addr_reply_port *port_msg)
1033{
1034 struct drm_dp_mst_port *port;
1035 bool ret;
1036 bool created = false;
1037 int old_pdt = 0;
1038 int old_ddps = 0;
1039 port = drm_dp_get_port(mstb, port_msg->port_number);
1040 if (!port) {
1041 port = kzalloc(sizeof(*port), GFP_KERNEL);
1042 if (!port)
1043 return;
1044 kref_init(&port->kref);
1045 port->parent = mstb;
1046 port->port_num = port_msg->port_number;
1047 port->mgr = mstb->mgr;
1048 port->aux.name = "DPMST";
1049 port->aux.dev = dev;
1050 created = true;
1051 } else {
1052 old_pdt = port->pdt;
1053 old_ddps = port->ddps;
1054 }
1055
1056 port->pdt = port_msg->peer_device_type;
1057 port->input = port_msg->input_port;
1058 port->mcs = port_msg->mcs;
1059 port->ddps = port_msg->ddps;
1060 port->ldps = port_msg->legacy_device_plug_status;
1061 port->dpcd_rev = port_msg->dpcd_revision;
1062 port->num_sdp_streams = port_msg->num_sdp_streams;
1063 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1064 memcpy(port->guid, port_msg->peer_guid, 16);
1065
1066 /* manage mstb port lists with mgr lock - take a reference
1067 for this list */
1068 if (created) {
1069 mutex_lock(&mstb->mgr->lock);
1070 kref_get(&port->kref);
1071 list_add(&port->next, &mstb->ports);
1072 mutex_unlock(&mstb->mgr->lock);
1073 }
1074
1075 if (old_ddps != port->ddps) {
1076 if (port->ddps) {
1077 drm_dp_check_port_guid(mstb, port);
1078 if (!port->input)
1079 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1080 } else {
1081 port->guid_valid = false;
1082 port->available_pbn = 0;
1083 }
1084 }
1085
1086 if (old_pdt != port->pdt && !port->input) {
1087 drm_dp_port_teardown_pdt(port, old_pdt);
1088
1089 ret = drm_dp_port_setup_pdt(port);
1090 if (ret == true) {
1091 drm_dp_send_link_address(mstb->mgr, port->mstb);
1092 port->mstb->link_address_sent = true;
1093 }
1094 }
1095
1096 if (created && !port->input) {
1097 char proppath[255];
d87af4d1 1098 build_mst_prop_path(port, mstb, proppath, sizeof(proppath));
ad7f8a1f
DA		 1099 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1100 }
1101
1102 /* put reference to this port */
1103 drm_dp_put_port(port);
1104}
1105
1106static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1107 struct drm_dp_connection_status_notify *conn_stat)
1108{
1109 struct drm_dp_mst_port *port;
1110 int old_pdt;
1111 int old_ddps;
1112 bool dowork = false;
1113 port = drm_dp_get_port(mstb, conn_stat->port_number);
1114 if (!port)
1115 return;
1116
1117 old_ddps = port->ddps;
1118 old_pdt = port->pdt;
1119 port->pdt = conn_stat->peer_device_type;
1120 port->mcs = conn_stat->message_capability_status;
1121 port->ldps = conn_stat->legacy_device_plug_status;
1122 port->ddps = conn_stat->displayport_device_plug_status;
1123
1124 if (old_ddps != port->ddps) {
1125 if (port->ddps) {
1126 drm_dp_check_port_guid(mstb, port);
1127 dowork = true;
1128 } else {
1129 port->guid_valid = false;
1130 port->available_pbn = 0;
1131 }
1132 }
1133 if (old_pdt != port->pdt && !port->input) {
1134 drm_dp_port_teardown_pdt(port, old_pdt);
1135
1136 if (drm_dp_port_setup_pdt(port))
1137 dowork = true;
1138 }
1139
1140 drm_dp_put_port(port);
1141 if (dowork)
1142 queue_work(system_long_wq, &mstb->mgr->work);
1143
1144}
1145
1146static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1147 u8 lct, u8 *rad)
1148{
1149 struct drm_dp_mst_branch *mstb;
1150 struct drm_dp_mst_port *port;
1151 int i;
1152 /* find the port by iterating down */
1153 mstb = mgr->mst_primary;
1154
1155 for (i = 0; i < lct - 1; i++) {
1156 int shift = (i % 2) ? 0 : 4;
1157 int port_num = rad[i / 2] >> shift;
1158
1159 list_for_each_entry(port, &mstb->ports, next) {
1160 if (port->port_num == port_num) {
1161 if (!port->mstb) {
1162 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1163 return NULL;
1164 }
1165
1166 mstb = port->mstb;
1167 break;
1168 }
1169 }
1170 }
1171 kref_get(&mstb->kref);
1172 return mstb;
1173}
1174
1175static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1176 struct drm_dp_mst_branch *mstb)
1177{
1178 struct drm_dp_mst_port *port;
1179
1180 if (!mstb->link_address_sent) {
1181 drm_dp_send_link_address(mgr, mstb);
1182 mstb->link_address_sent = true;
1183 }
1184 list_for_each_entry(port, &mstb->ports, next) {
1185 if (port->input)
1186 continue;
1187
1188 if (!port->ddps)
1189 continue;
1190
1191 if (!port->available_pbn)
1192 drm_dp_send_enum_path_resources(mgr, mstb, port);
1193
1194 if (port->mstb)
1195 drm_dp_check_and_send_link_address(mgr, port->mstb);
1196 }
1197}
1198
1199static void drm_dp_mst_link_probe_work(struct work_struct *work)
1200{
1201 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1202
1203 drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
1204
1205}
1206
1207static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1208 u8 *guid)
1209{
1210 static u8 zero_guid[16];
1211
1212 if (!memcmp(guid, zero_guid, 16)) {
1213 u64 salt = get_jiffies_64();
1214 memcpy(&guid[0], &salt, sizeof(u64));
1215 memcpy(&guid[8], &salt, sizeof(u64));
1216 return false;
1217 }
1218 return true;
1219}
1220
1221#if 0
1222static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1223{
1224 struct drm_dp_sideband_msg_req_body req;
1225
1226 req.req_type = DP_REMOTE_DPCD_READ;
1227 req.u.dpcd_read.port_number = port_num;
1228 req.u.dpcd_read.dpcd_address = offset;
1229 req.u.dpcd_read.num_bytes = num_bytes;
1230 drm_dp_encode_sideband_req(&req, msg);
1231
1232 return 0;
1233}
1234#endif
1235
1236static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1237 bool up, u8 *msg, int len)
1238{
1239 int ret;
1240 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1241 int tosend, total, offset;
1242 int retries = 0;
1243
1244retry:
1245 total = len;
1246 offset = 0;
1247 do {
1248 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1249
1250 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1251 &msg[offset],
1252 tosend);
1253 if (ret != tosend) {
1254 if (ret == -EIO && retries < 5) {
1255 retries++;
1256 goto retry;
1257 }
1258 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1259 WARN(1, "fail\n");
1260
1261 return -EIO;
1262 }
1263 offset += tosend;
1264 total -= tosend;
1265 } while (total > 0);
1266 return 0;
1267}
1268
1269static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1270 struct drm_dp_sideband_msg_tx *txmsg)
1271{
1272 struct drm_dp_mst_branch *mstb = txmsg->dst;
1273
1274 /* both msg slots are full */
1275 if (txmsg->seqno == -1) {
1276 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1277 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1278 return -EAGAIN;
1279 }
1280 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1281 txmsg->seqno = mstb->last_seqno;
1282 mstb->last_seqno ^= 1;
1283 } else if (mstb->tx_slots[0] == NULL)
1284 txmsg->seqno = 0;
1285 else
1286 txmsg->seqno = 1;
1287 mstb->tx_slots[txmsg->seqno] = txmsg;
1288 }
1289 hdr->broadcast = 0;
1290 hdr->path_msg = txmsg->path_msg;
1291 hdr->lct = mstb->lct;
1292 hdr->lcr = mstb->lct - 1;
1293 if (mstb->lct > 1)
1294 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1295 hdr->seqno = txmsg->seqno;
1296 return 0;
1297}
1298/*
1299 * process a single block of the next message in the sideband queue
1300 */
1301static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1302 struct drm_dp_sideband_msg_tx *txmsg,
1303 bool up)
1304{
1305 u8 chunk[48];
1306 struct drm_dp_sideband_msg_hdr hdr;
1307 int len, space, idx, tosend;
1308 int ret;
1309
bf3719c0
DL		 1310 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1311
ad7f8a1f
DA		 1312 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1313 txmsg->seqno = -1;
1314 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1315 }
1316
1317 /* make hdr from dst mst - for replies use seqno
1318 otherwise assign one */
1319 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1320 if (ret < 0)
1321 return ret;
1322
1323 /* amount left to send in this message */
1324 len = txmsg->cur_len - txmsg->cur_offset;
1325
1326 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1327 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1328
1329 tosend = min(len, space);
1330 if (len == txmsg->cur_len)
1331 hdr.somt = 1;
1332 if (space >= len)
1333 hdr.eomt = 1;
1334
1335
1336 hdr.msg_len = tosend + 1;
1337 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1338 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1339 /* add crc at end */
1340 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1341 idx += tosend + 1;
1342
1343 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1344 if (ret) {
1345 DRM_DEBUG_KMS("sideband msg failed to send\n");
1346 return ret;
1347 }
1348
1349 txmsg->cur_offset += tosend;
1350 if (txmsg->cur_offset == txmsg->cur_len) {
1351 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1352 return 1;
1353 }
1354 return 0;
1355}
1356
1357/* must be called holding qlock */
1358static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1359{
1360 struct drm_dp_sideband_msg_tx *txmsg;
1361 int ret;
1362
1363 /* construct a chunk from the first msg in the tx_msg queue */
1364 if (list_empty(&mgr->tx_msg_downq)) {
1365 mgr->tx_down_in_progress = false;
1366 return;
1367 }
1368 mgr->tx_down_in_progress = true;
1369
1370 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1371 ret = process_single_tx_qlock(mgr, txmsg, false);
1372 if (ret == 1) {
1373 /* txmsg is sent it should be in the slots now */
1374 list_del(&txmsg->next);
1375 } else if (ret) {
1376 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1377 list_del(&txmsg->next);
1378 if (txmsg->seqno != -1)
1379 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1380 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1381 wake_up(&mgr->tx_waitq);
1382 }
1383 if (list_empty(&mgr->tx_msg_downq)) {
1384 mgr->tx_down_in_progress = false;
1385 return;
1386 }
1387}
1388
1389/* called holding qlock */
1390static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1391{
1392 struct drm_dp_sideband_msg_tx *txmsg;
1393 int ret;
1394
1395 /* construct a chunk from the first msg in the tx_msg queue */
1396 if (list_empty(&mgr->tx_msg_upq)) {
1397 mgr->tx_up_in_progress = false;
1398 return;
1399 }
1400
1401 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1402 ret = process_single_tx_qlock(mgr, txmsg, true);
1403 if (ret == 1) {
1404 /* up txmsgs aren't put in slots - so free after we send it */
1405 list_del(&txmsg->next);
1406 kfree(txmsg);
1407 } else if (ret)
1408 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1409 mgr->tx_up_in_progress = true;
1410}
1411
1412static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1413 struct drm_dp_sideband_msg_tx *txmsg)
1414{
1415 mutex_lock(&mgr->qlock);
1416 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1417 if (!mgr->tx_down_in_progress)
1418 process_single_down_tx_qlock(mgr);
1419 mutex_unlock(&mgr->qlock);
1420}
1421
1422static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1423 struct drm_dp_mst_branch *mstb)
1424{
1425 int len;
1426 struct drm_dp_sideband_msg_tx *txmsg;
1427 int ret;
1428
1429 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1430 if (!txmsg)
1431 return -ENOMEM;
1432
1433 txmsg->dst = mstb;
1434 len = build_link_address(txmsg);
1435
1436 drm_dp_queue_down_tx(mgr, txmsg);
1437
1438 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1439 if (ret > 0) {
1440 int i;
1441
1442 if (txmsg->reply.reply_type == 1)
1443 DRM_DEBUG_KMS("link address nak received\n");
1444 else {
1445 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1446 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1447 DRM_DEBUG_KMS("port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i,
1448 txmsg->reply.u.link_addr.ports[i].input_port,
1449 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1450 txmsg->reply.u.link_addr.ports[i].port_number,
1451 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1452 txmsg->reply.u.link_addr.ports[i].mcs,
1453 txmsg->reply.u.link_addr.ports[i].ddps,
1454 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1455 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1456 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1457 }
1458 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1459 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1460 }
1461 (*mgr->cbs->hotplug)(mgr);
1462 }
1463 } else
1464 DRM_DEBUG_KMS("link address failed %d\n", ret);
1465
1466 kfree(txmsg);
1467 return 0;
1468}
1469
1470static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1471 struct drm_dp_mst_branch *mstb,
1472 struct drm_dp_mst_port *port)
1473{
1474 int len;
1475 struct drm_dp_sideband_msg_tx *txmsg;
1476 int ret;
1477
1478 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1479 if (!txmsg)
1480 return -ENOMEM;
1481
1482 txmsg->dst = mstb;
1483 len = build_enum_path_resources(txmsg, port->port_num);
1484
1485 drm_dp_queue_down_tx(mgr, txmsg);
1486
1487 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1488 if (ret > 0) {
1489 if (txmsg->reply.reply_type == 1)
1490 DRM_DEBUG_KMS("enum path resources nak received\n");
1491 else {
1492 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1493 DRM_ERROR("got incorrect port in response\n");
1494 DRM_DEBUG_KMS("enum path resources %d: %d %d\n", txmsg->reply.u.path_resources.port_number, txmsg->reply.u.path_resources.full_payload_bw_number,
1495 txmsg->reply.u.path_resources.avail_payload_bw_number);
1496 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1497 }
1498 }
1499
1500 kfree(txmsg);
1501 return 0;
1502}
1503
8fa6a425
TR		 1504static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1505 struct drm_dp_mst_port *port,
1506 int id,
1507 int pbn)
ad7f8a1f
DA		 1508{
1509 struct drm_dp_sideband_msg_tx *txmsg;
1510 struct drm_dp_mst_branch *mstb;
1511 int len, ret;
1512
1513 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1514 if (!mstb)
1515 return -EINVAL;
1516
1517 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1518 if (!txmsg) {
1519 ret = -ENOMEM;
1520 goto fail_put;
1521 }
1522
1523 txmsg->dst = mstb;
1524 len = build_allocate_payload(txmsg, port->port_num,
1525 id,
1526 pbn);
1527
1528 drm_dp_queue_down_tx(mgr, txmsg);
1529
1530 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1531 if (ret > 0) {
1532 if (txmsg->reply.reply_type == 1) {
1533 ret = -EINVAL;
1534 } else
1535 ret = 0;
1536 }
1537 kfree(txmsg);
1538fail_put:
1539 drm_dp_put_mst_branch_device(mstb);
1540 return ret;
1541}
1542
1543static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1544 int id,
1545 struct drm_dp_payload *payload)
1546{
1547 int ret;
1548
1549 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1550 if (ret < 0) {
1551 payload->payload_state = 0;
1552 return ret;
1553 }
1554 payload->payload_state = DP_PAYLOAD_LOCAL;
1555 return 0;
1556}
1557
8fa6a425
TR		 1558static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1559 struct drm_dp_mst_port *port,
1560 int id,
1561 struct drm_dp_payload *payload)
ad7f8a1f
DA		 1562{
1563 int ret;
1564 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1565 if (ret < 0)
1566 return ret;
1567 payload->payload_state = DP_PAYLOAD_REMOTE;
1568 return ret;
1569}
1570
8fa6a425
TR		 1571static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1572 struct drm_dp_mst_port *port,
1573 int id,
1574 struct drm_dp_payload *payload)
ad7f8a1f
DA		 1575{
1576 DRM_DEBUG_KMS("\n");
1577 /* its okay for these to fail */
1578 if (port) {
1579 drm_dp_payload_send_msg(mgr, port, id, 0);
1580 }
1581
1582 drm_dp_dpcd_write_payload(mgr, id, payload);
dfda0df3 1583 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
ad7f8a1f
DA		 1584 return 0;
1585}
1586
8fa6a425
TR		 1587static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1588 int id,
1589 struct drm_dp_payload *payload)
ad7f8a1f
DA		 1590{
1591 payload->payload_state = 0;
1592 return 0;
1593}
1594
1595/**
1596 * drm_dp_update_payload_part1() - Execute payload update part 1
1597 * @mgr: manager to use.
1598 *
1599 * This iterates over all proposed virtual channels, and tries to
1600 * allocate space in the link for them. For 0->slots transitions,
1601 * this step just writes the VCPI to the MST device. For slots->0
1602 * transitions, this writes the updated VCPIs and removes the
1603 * remote VC payloads.
1604 *
1605 * after calling this the driver should generate ACT and payload
1606 * packets.
1607 */
1608int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1609{
dfda0df3 1610 int i, j;
ad7f8a1f
DA		 1611 int cur_slots = 1;
1612 struct drm_dp_payload req_payload;
1613 struct drm_dp_mst_port *port;
1614
1615 mutex_lock(&mgr->payload_lock);
1616 for (i = 0; i < mgr->max_payloads; i++) {
1617 /* solve the current payloads - compare to the hw ones
1618 - update the hw view */
1619 req_payload.start_slot = cur_slots;
1620 if (mgr->proposed_vcpis[i]) {
1621 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1622 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1623 } else {
1624 port = NULL;
1625 req_payload.num_slots = 0;
1626 }
dfda0df3
DA		 1627
1628 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1629 mgr->payloads[i].start_slot = req_payload.start_slot;
1630 }
ad7f8a1f 1631 /* work out what is required to happen with this payload */
dfda0df3 1632 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
ad7f8a1f
DA		 1633
1634 /* need to push an update for this payload */
1635 if (req_payload.num_slots) {
dfda0df3 1636 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
ad7f8a1f
DA		 1637 mgr->payloads[i].num_slots = req_payload.num_slots;
1638 } else if (mgr->payloads[i].num_slots) {
1639 mgr->payloads[i].num_slots = 0;
dfda0df3 1640 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
ad7f8a1f 1641 req_payload.payload_state = mgr->payloads[i].payload_state;
dfda0df3
DA		 1642 mgr->payloads[i].start_slot = 0;
1643 }
ad7f8a1f
DA		 1644 mgr->payloads[i].payload_state = req_payload.payload_state;
1645 }
1646 cur_slots += req_payload.num_slots;
1647 }
dfda0df3
DA		 1648
1649 for (i = 0; i < mgr->max_payloads; i++) {
1650 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1651 DRM_DEBUG_KMS("removing payload %d\n", i);
1652 for (j = i; j < mgr->max_payloads - 1; j++) {
1653 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1654 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1655 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1656 set_bit(j + 1, &mgr->payload_mask);
1657 } else {
1658 clear_bit(j + 1, &mgr->payload_mask);
1659 }
1660 }
1661 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1662 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1663 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1664
1665 }
1666 }
ad7f8a1f
DA		 1667 mutex_unlock(&mgr->payload_lock);
1668
1669 return 0;
1670}
1671EXPORT_SYMBOL(drm_dp_update_payload_part1);
1672
1673/**
1674 * drm_dp_update_payload_part2() - Execute payload update part 2
1675 * @mgr: manager to use.
1676 *
1677 * This iterates over all proposed virtual channels, and tries to
1678 * allocate space in the link for them. For 0->slots transitions,
1679 * this step writes the remote VC payload commands. For slots->0
1680 * this just resets some internal state.
1681 */
1682int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1683{
1684 struct drm_dp_mst_port *port;
1685 int i;
7389ad4b 1686 int ret = 0;
ad7f8a1f
DA		 1687 mutex_lock(&mgr->payload_lock);
1688 for (i = 0; i < mgr->max_payloads; i++) {
1689
1690 if (!mgr->proposed_vcpis[i])
1691 continue;
1692
1693 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1694
1695 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1696 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
dfda0df3 1697 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
ad7f8a1f 1698 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
dfda0df3 1699 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
ad7f8a1f
DA		 1700 }
1701 if (ret) {
1702 mutex_unlock(&mgr->payload_lock);
1703 return ret;
1704 }
1705 }
1706 mutex_unlock(&mgr->payload_lock);
1707 return 0;
1708}
1709EXPORT_SYMBOL(drm_dp_update_payload_part2);
1710
1711#if 0 /* unused as of yet */
1712static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1713 struct drm_dp_mst_port *port,
1714 int offset, int size)
1715{
1716 int len;
1717 struct drm_dp_sideband_msg_tx *txmsg;
1718
1719 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1720 if (!txmsg)
1721 return -ENOMEM;
1722
1723 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1724 txmsg->dst = port->parent;
1725
1726 drm_dp_queue_down_tx(mgr, txmsg);
1727
1728 return 0;
1729}
1730#endif
1731
1732static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1733 struct drm_dp_mst_port *port,
1734 int offset, int size, u8 *bytes)
1735{
1736 int len;
1737 int ret;
1738 struct drm_dp_sideband_msg_tx *txmsg;
1739 struct drm_dp_mst_branch *mstb;
1740
1741 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1742 if (!mstb)
1743 return -EINVAL;
1744
1745 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1746 if (!txmsg) {
1747 ret = -ENOMEM;
1748 goto fail_put;
1749 }
1750
1751 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1752 txmsg->dst = mstb;
1753
1754 drm_dp_queue_down_tx(mgr, txmsg);
1755
1756 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1757 if (ret > 0) {
1758 if (txmsg->reply.reply_type == 1) {
1759 ret = -EINVAL;
1760 } else
1761 ret = 0;
1762 }
1763 kfree(txmsg);
1764fail_put:
1765 drm_dp_put_mst_branch_device(mstb);
1766 return ret;
1767}
1768
1769static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1770{
1771 struct drm_dp_sideband_msg_reply_body reply;
1772
1773 reply.reply_type = 1;
1774 reply.req_type = req_type;
1775 drm_dp_encode_sideband_reply(&reply, msg);
1776 return 0;
1777}
1778
1779static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1780 struct drm_dp_mst_branch *mstb,
1781 int req_type, int seqno, bool broadcast)
1782{
1783 struct drm_dp_sideband_msg_tx *txmsg;
1784
1785 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1786 if (!txmsg)
1787 return -ENOMEM;
1788
1789 txmsg->dst = mstb;
1790 txmsg->seqno = seqno;
1791 drm_dp_encode_up_ack_reply(txmsg, req_type);
1792
1793 mutex_lock(&mgr->qlock);
1794 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1795 if (!mgr->tx_up_in_progress) {
1796 process_single_up_tx_qlock(mgr);
1797 }
1798 mutex_unlock(&mgr->qlock);
1799 return 0;
1800}
1801
1802static int drm_dp_get_vc_payload_bw(int dp_link_bw, int dp_link_count)
1803{
1804 switch (dp_link_bw) {
1805 case DP_LINK_BW_1_62:
1806 return 3 * dp_link_count;
1807 case DP_LINK_BW_2_7:
1808 return 5 * dp_link_count;
1809 case DP_LINK_BW_5_4:
1810 return 10 * dp_link_count;
1811 }
c11cda52 1812 BUG();
ad7f8a1f
DA		 1813}
1814
1815/**
1816 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1817 * @mgr: manager to set state for
1818 * @mst_state: true to enable MST on this connector - false to disable.
1819 *
1820 * This is called by the driver when it detects an MST capable device plugged
1821 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1822 */
1823int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1824{
1825 int ret = 0;
1826 struct drm_dp_mst_branch *mstb = NULL;
1827
1828 mutex_lock(&mgr->lock);
1829 if (mst_state == mgr->mst_state)
1830 goto out_unlock;
1831
1832 mgr->mst_state = mst_state;
1833 /* set the device into MST mode */
1834 if (mst_state) {
1835 WARN_ON(mgr->mst_primary);
1836
1837 /* get dpcd info */
1838 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1839 if (ret != DP_RECEIVER_CAP_SIZE) {
1840 DRM_DEBUG_KMS("failed to read DPCD\n");
1841 goto out_unlock;
1842 }
1843
1844 mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1], mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK);
1845 mgr->total_pbn = 2560;
1846 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1847 mgr->avail_slots = mgr->total_slots;
1848
1849 /* add initial branch device at LCT 1 */
1850 mstb = drm_dp_add_mst_branch_device(1, NULL);
1851 if (mstb == NULL) {
1852 ret = -ENOMEM;
1853 goto out_unlock;
1854 }
1855 mstb->mgr = mgr;
1856
1857 /* give this the main reference */
1858 mgr->mst_primary = mstb;
1859 kref_get(&mgr->mst_primary->kref);
1860
1861 {
1862 struct drm_dp_payload reset_pay;
1863 reset_pay.start_slot = 0;
1864 reset_pay.num_slots = 0x3f;
1865 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1866 }
1867
1868 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1869 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1870 if (ret < 0) {
1871 goto out_unlock;
1872 }
1873
1874
1875 /* sort out guid */
1876 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1877 if (ret != 16) {
1878 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1879 goto out_unlock;
1880 }
1881
1882 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1883 if (!mgr->guid_valid) {
1884 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1885 mgr->guid_valid = true;
1886 }
1887
1888 queue_work(system_long_wq, &mgr->work);
1889
1890 ret = 0;
1891 } else {
1892 /* disable MST on the device */
1893 mstb = mgr->mst_primary;
1894 mgr->mst_primary = NULL;
1895 /* this can fail if the device is gone */
1896 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1897 ret = 0;
1898 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1899 mgr->payload_mask = 0;
1900 set_bit(0, &mgr->payload_mask);
dfda0df3 1901 mgr->vcpi_mask = 0;
ad7f8a1f
DA		 1902 }
1903
1904out_unlock:
1905 mutex_unlock(&mgr->lock);
1906 if (mstb)
1907 drm_dp_put_mst_branch_device(mstb);
1908 return ret;
1909
1910}
1911EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1912
1913/**
1914 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1915 * @mgr: manager to suspend
1916 *
1917 * This function tells the MST device that we can't handle UP messages
1918 * anymore. This should stop it from sending any since we are suspended.
1919 */
1920void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1921{
1922 mutex_lock(&mgr->lock);
1923 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1924 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1925 mutex_unlock(&mgr->lock);
1926}
1927EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1928
1929/**
1930 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1931 * @mgr: manager to resume
1932 *
1933 * This will fetch DPCD and see if the device is still there,
1934 * if it is, it will rewrite the MSTM control bits, and return.
1935 *
1936 * if the device fails this returns -1, and the driver should do
1937 * a full MST reprobe, in case we were undocked.
1938 */
1939int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1940{
1941 int ret = 0;
1942
1943 mutex_lock(&mgr->lock);
1944
1945 if (mgr->mst_primary) {
1946 int sret;
1947 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1948 if (sret != DP_RECEIVER_CAP_SIZE) {
1949 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1950 ret = -1;
1951 goto out_unlock;
1952 }
1953
1954 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1955 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1956 if (ret < 0) {
1957 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1958 ret = -1;
1959 goto out_unlock;
1960 }
1961 ret = 0;
1962 } else
1963 ret = -1;
1964
1965out_unlock:
1966 mutex_unlock(&mgr->lock);
1967 return ret;
1968}
1969EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
1970
1971static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
1972{
1973 int len;
1974 u8 replyblock[32];
1975 int replylen, origlen, curreply;
1976 int ret;
1977 struct drm_dp_sideband_msg_rx *msg;
1978 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
1979 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
1980
1981 len = min(mgr->max_dpcd_transaction_bytes, 16);
1982 ret = drm_dp_dpcd_read(mgr->aux, basereg,
1983 replyblock, len);
1984 if (ret != len) {
1985 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
1986 return;
1987 }
1988 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
1989 if (!ret) {
1990 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
1991 return;
1992 }
1993 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
1994
1995 origlen = replylen;
1996 replylen -= len;
1997 curreply = len;
1998 while (replylen > 0) {
1999 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
2000 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2001 replyblock, len);
2002 if (ret != len) {
2003 DRM_DEBUG_KMS("failed to read a chunk\n");
2004 }
2005 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2006 if (ret == false)
2007 DRM_DEBUG_KMS("failed to build sideband msg\n");
2008 curreply += len;
2009 replylen -= len;
2010 }
2011}
2012
2013static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2014{
2015 int ret = 0;
2016
2017 drm_dp_get_one_sb_msg(mgr, false);
2018
2019 if (mgr->down_rep_recv.have_eomt) {
2020 struct drm_dp_sideband_msg_tx *txmsg;
2021 struct drm_dp_mst_branch *mstb;
2022 int slot = -1;
2023 mstb = drm_dp_get_mst_branch_device(mgr,
2024 mgr->down_rep_recv.initial_hdr.lct,
2025 mgr->down_rep_recv.initial_hdr.rad);
2026
2027 if (!mstb) {
2028 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2029 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2030 return 0;
2031 }
2032
2033 /* find the message */
2034 slot = mgr->down_rep_recv.initial_hdr.seqno;
2035 mutex_lock(&mgr->qlock);
2036 txmsg = mstb->tx_slots[slot];
2037 /* remove from slots */
2038 mutex_unlock(&mgr->qlock);
2039
2040 if (!txmsg) {
2041 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2042 mstb,
2043 mgr->down_rep_recv.initial_hdr.seqno,
2044 mgr->down_rep_recv.initial_hdr.lct,
2045 mgr->down_rep_recv.initial_hdr.rad[0],
2046 mgr->down_rep_recv.msg[0]);
2047 drm_dp_put_mst_branch_device(mstb);
2048 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2049 return 0;
2050 }
2051
2052 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2053 if (txmsg->reply.reply_type == 1) {
2054 DRM_DEBUG_KMS("Got NAK reply: req 0x%02x, reason 0x%02x, nak data 0x%02x\n", txmsg->reply.req_type, txmsg->reply.u.nak.reason, txmsg->reply.u.nak.nak_data);
2055 }
2056
2057 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2058 drm_dp_put_mst_branch_device(mstb);
2059
2060 mutex_lock(&mgr->qlock);
2061 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2062 mstb->tx_slots[slot] = NULL;
2063 mutex_unlock(&mgr->qlock);
2064
2065 wake_up(&mgr->tx_waitq);
2066 }
2067 return ret;
2068}
2069
2070static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2071{
2072 int ret = 0;
2073 drm_dp_get_one_sb_msg(mgr, true);
2074
2075 if (mgr->up_req_recv.have_eomt) {
2076 struct drm_dp_sideband_msg_req_body msg;
2077 struct drm_dp_mst_branch *mstb;
2078 bool seqno;
2079 mstb = drm_dp_get_mst_branch_device(mgr,
2080 mgr->up_req_recv.initial_hdr.lct,
2081 mgr->up_req_recv.initial_hdr.rad);
2082 if (!mstb) {
2083 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2084 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2085 return 0;
2086 }
2087
2088 seqno = mgr->up_req_recv.initial_hdr.seqno;
2089 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2090
2091 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2092 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2093 drm_dp_update_port(mstb, &msg.u.conn_stat);
2094 DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg.u.conn_stat.port_number, msg.u.conn_stat.legacy_device_plug_status, msg.u.conn_stat.displayport_device_plug_status, msg.u.conn_stat.message_capability_status, msg.u.conn_stat.input_port, msg.u.conn_stat.peer_device_type);
2095 (*mgr->cbs->hotplug)(mgr);
2096
2097 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2098 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2099 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2100 }
2101
2102 drm_dp_put_mst_branch_device(mstb);
2103 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2104 }
2105 return ret;
2106}
2107
2108/**
2109 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2110 * @mgr: manager to notify irq for.
2111 * @esi: 4 bytes from SINK_COUNT_ESI
295ee853 2112 * @handled: whether the hpd interrupt was consumed or not
ad7f8a1f
DA		 2113 *
2114 * This should be called from the driver when it detects a short IRQ,
2115 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2116 * topology manager will process the sideband messages received as a result
2117 * of this.
2118 */
2119int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2120{
2121 int ret = 0;
2122 int sc;
2123 *handled = false;
2124 sc = esi[0] & 0x3f;
2125
2126 if (sc != mgr->sink_count) {
2127 mgr->sink_count = sc;
2128 *handled = true;
2129 }
2130
2131 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2132 ret = drm_dp_mst_handle_down_rep(mgr);
2133 *handled = true;
2134 }
2135
2136 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2137 ret |= drm_dp_mst_handle_up_req(mgr);
2138 *handled = true;
2139 }
2140
2141 drm_dp_mst_kick_tx(mgr);
2142 return ret;
2143}
2144EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2145
2146/**
2147 * drm_dp_mst_detect_port() - get connection status for an MST port
2148 * @mgr: manager for this port
2149 * @port: unverified pointer to a port
2150 *
2151 * This returns the current connection state for a port. It validates the
2152 * port pointer still exists so the caller doesn't require a reference
2153 */
2154enum drm_connector_status drm_dp_mst_detect_port(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2155{
2156 enum drm_connector_status status = connector_status_disconnected;
2157
2158 /* we need to search for the port in the mgr in case its gone */
2159 port = drm_dp_get_validated_port_ref(mgr, port);
2160 if (!port)
2161 return connector_status_disconnected;
2162
2163 if (!port->ddps)
2164 goto out;
2165
2166 switch (port->pdt) {
2167 case DP_PEER_DEVICE_NONE:
2168 case DP_PEER_DEVICE_MST_BRANCHING:
2169 break;
2170
2171 case DP_PEER_DEVICE_SST_SINK:
2172 status = connector_status_connected;
2173 break;
2174 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2175 if (port->ldps)
2176 status = connector_status_connected;
2177 break;
2178 }
2179out:
2180 drm_dp_put_port(port);
2181 return status;
2182}
2183EXPORT_SYMBOL(drm_dp_mst_detect_port);
2184
2185/**
2186 * drm_dp_mst_get_edid() - get EDID for an MST port
2187 * @connector: toplevel connector to get EDID for
2188 * @mgr: manager for this port
2189 * @port: unverified pointer to a port.
2190 *
2191 * This returns an EDID for the port connected to a connector,
2192 * It validates the pointer still exists so the caller doesn't require a
2193 * reference.
2194 */
2195struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2196{
2197 struct edid *edid = NULL;
2198
2199 /* we need to search for the port in the mgr in case its gone */
2200 port = drm_dp_get_validated_port_ref(mgr, port);
2201 if (!port)
2202 return NULL;
2203
2204 edid = drm_get_edid(connector, &port->aux.ddc);
2205 drm_dp_put_port(port);
2206 return edid;
2207}
2208EXPORT_SYMBOL(drm_dp_mst_get_edid);
2209
2210/**
2211 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2212 * @mgr: manager to use
2213 * @pbn: payload bandwidth to convert into slots.
2214 */
2215int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2216 int pbn)
2217{
2218 int num_slots;
2219
2220 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2221
2222 if (num_slots > mgr->avail_slots)
2223 return -ENOSPC;
2224 return num_slots;
2225}
2226EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2227
2228static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2229 struct drm_dp_vcpi *vcpi, int pbn)
2230{
2231 int num_slots;
2232 int ret;
2233
2234 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2235
2236 if (num_slots > mgr->avail_slots)
2237 return -ENOSPC;
2238
2239 vcpi->pbn = pbn;
2240 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2241 vcpi->num_slots = num_slots;
2242
2243 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2244 if (ret < 0)
2245 return ret;
2246 return 0;
2247}
2248
2249/**
2250 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2251 * @mgr: manager for this port
2252 * @port: port to allocate a virtual channel for.
2253 * @pbn: payload bandwidth number to request
2254 * @slots: returned number of slots for this PBN.
2255 */
2256bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2257{
2258 int ret;
2259
2260 port = drm_dp_get_validated_port_ref(mgr, port);
2261 if (!port)
2262 return false;
2263
2264 if (port->vcpi.vcpi > 0) {
2265 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2266 if (pbn == port->vcpi.pbn) {
2267 *slots = port->vcpi.num_slots;
2268 return true;
2269 }
2270 }
2271
2272 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2273 if (ret) {
2274 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2275 goto out;
2276 }
2277 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2278 *slots = port->vcpi.num_slots;
2279
2280 drm_dp_put_port(port);
2281 return true;
2282out:
2283 return false;
2284}
2285EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2286
2287/**
2288 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2289 * @mgr: manager for this port
2290 * @port: unverified pointer to a port.
2291 *
2292 * This just resets the number of slots for the ports VCPI for later programming.
2293 */
2294void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2295{
2296 port = drm_dp_get_validated_port_ref(mgr, port);
2297 if (!port)
2298 return;
2299 port->vcpi.num_slots = 0;
2300 drm_dp_put_port(port);
2301}
2302EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2303
2304/**
2305 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2306 * @mgr: manager for this port
2307 * @port: unverified port to deallocate vcpi for
2308 */
2309void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2310{
2311 port = drm_dp_get_validated_port_ref(mgr, port);
2312 if (!port)
2313 return;
2314
2315 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2316 port->vcpi.num_slots = 0;
2317 port->vcpi.pbn = 0;
2318 port->vcpi.aligned_pbn = 0;
2319 port->vcpi.vcpi = 0;
2320 drm_dp_put_port(port);
2321}
2322EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2323
2324static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2325 int id, struct drm_dp_payload *payload)
2326{
2327 u8 payload_alloc[3], status;
2328 int ret;
2329 int retries = 0;
2330
2331 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2332 DP_PAYLOAD_TABLE_UPDATED);
2333
2334 payload_alloc[0] = id;
2335 payload_alloc[1] = payload->start_slot;
2336 payload_alloc[2] = payload->num_slots;
2337
2338 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2339 if (ret != 3) {
2340 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2341 goto fail;
2342 }
2343
2344retry:
2345 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2346 if (ret < 0) {
2347 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2348 goto fail;
2349 }
2350
2351 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2352 retries++;
2353 if (retries < 20) {
2354 usleep_range(10000, 20000);
2355 goto retry;
2356 }
2357 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2358 ret = -EINVAL;
2359 goto fail;
2360 }
2361 ret = 0;
2362fail:
2363 return ret;
2364}
2365
2366
2367/**
2368 * drm_dp_check_act_status() - Check ACT handled status.
2369 * @mgr: manager to use
2370 *
2371 * Check the payload status bits in the DPCD for ACT handled completion.
2372 */
2373int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2374{
2375 u8 status;
2376 int ret;
2377 int count = 0;
2378
2379 do {
2380 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2381
2382 if (ret < 0) {
2383 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2384 goto fail;
2385 }
2386
2387 if (status & DP_PAYLOAD_ACT_HANDLED)
2388 break;
2389 count++;
2390 udelay(100);
2391
2392 } while (count < 30);
2393
2394 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2395 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2396 ret = -EINVAL;
2397 goto fail;
2398 }
2399 return 0;
2400fail:
2401 return ret;
2402}
2403EXPORT_SYMBOL(drm_dp_check_act_status);
2404
2405/**
2406 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2407 * @clock: dot clock for the mode
2408 * @bpp: bpp for the mode.
2409 *
2410 * This uses the formula in the spec to calculate the PBN value for a mode.
2411 */
2412int drm_dp_calc_pbn_mode(int clock, int bpp)
2413{
2414 fixed20_12 pix_bw;
2415 fixed20_12 fbpp;
2416 fixed20_12 result;
2417 fixed20_12 margin, tmp;
2418 u32 res;
2419
2420 pix_bw.full = dfixed_const(clock);
2421 fbpp.full = dfixed_const(bpp);
2422 tmp.full = dfixed_const(8);
2423 fbpp.full = dfixed_div(fbpp, tmp);
2424
2425 result.full = dfixed_mul(pix_bw, fbpp);
2426 margin.full = dfixed_const(54);
2427 tmp.full = dfixed_const(64);
2428 margin.full = dfixed_div(margin, tmp);
2429 result.full = dfixed_div(result, margin);
2430
2431 margin.full = dfixed_const(1006);
2432 tmp.full = dfixed_const(1000);
2433 margin.full = dfixed_div(margin, tmp);
2434 result.full = dfixed_mul(result, margin);
2435
2436 result.full = dfixed_div(result, tmp);
2437 result.full = dfixed_ceil(result);
2438 res = dfixed_trunc(result);
2439 return res;
2440}
2441EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2442
2443static int test_calc_pbn_mode(void)
2444{
2445 int ret;
2446 ret = drm_dp_calc_pbn_mode(154000, 30);
2447 if (ret != 689)
2448 return -EINVAL;
2449 ret = drm_dp_calc_pbn_mode(234000, 30);
2450 if (ret != 1047)
2451 return -EINVAL;
2452 return 0;
2453}
2454
2455/* we want to kick the TX after we've ack the up/down IRQs. */
2456static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2457{
2458 queue_work(system_long_wq, &mgr->tx_work);
2459}
2460
2461static void drm_dp_mst_dump_mstb(struct seq_file *m,
2462 struct drm_dp_mst_branch *mstb)
2463{
2464 struct drm_dp_mst_port *port;
2465 int tabs = mstb->lct;
2466 char prefix[10];
2467 int i;
2468
2469 for (i = 0; i < tabs; i++)
2470 prefix[i] = '\t';
2471 prefix[i] = '\0';
2472
2473 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2474 list_for_each_entry(port, &mstb->ports, next) {
2475 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2476 if (port->mstb)
2477 drm_dp_mst_dump_mstb(m, port->mstb);
2478 }
2479}
2480
2481static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2482 char *buf)
2483{
2484 int ret;
2485 int i;
2486 for (i = 0; i < 4; i++) {
2487 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2488 if (ret != 16)
2489 break;
2490 }
2491 if (i == 4)
2492 return true;
2493 return false;
2494}
2495
2496/**
2497 * drm_dp_mst_dump_topology(): dump topology to seq file.
2498 * @m: seq_file to dump output to
2499 * @mgr: manager to dump current topology for.
2500 *
2501 * helper to dump MST topology to a seq file for debugfs.
2502 */
2503void drm_dp_mst_dump_topology(struct seq_file *m,
2504 struct drm_dp_mst_topology_mgr *mgr)
2505{
2506 int i;
2507 struct drm_dp_mst_port *port;
2508 mutex_lock(&mgr->lock);
2509 if (mgr->mst_primary)
2510 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2511
2512 /* dump VCPIs */
2513 mutex_unlock(&mgr->lock);
2514
2515 mutex_lock(&mgr->payload_lock);
dfda0df3 2516 seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask);
ad7f8a1f
DA		 2517
2518 for (i = 0; i < mgr->max_payloads; i++) {
2519 if (mgr->proposed_vcpis[i]) {
2520 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2521 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2522 } else
2523 seq_printf(m, "vcpi %d:unsed\n", i);
2524 }
2525 for (i = 0; i < mgr->max_payloads; i++) {
2526 seq_printf(m, "payload %d: %d, %d, %d\n",
2527 i,
2528 mgr->payloads[i].payload_state,
2529 mgr->payloads[i].start_slot,
2530 mgr->payloads[i].num_slots);
2531
2532
2533 }
2534 mutex_unlock(&mgr->payload_lock);
2535
2536 mutex_lock(&mgr->lock);
2537 if (mgr->mst_primary) {
2538 u8 buf[64];
2539 bool bret;
2540 int ret;
2541 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2542 seq_printf(m, "dpcd: ");
2543 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2544 seq_printf(m, "%02x ", buf[i]);
2545 seq_printf(m, "\n");
2546 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2547 seq_printf(m, "faux/mst: ");
2548 for (i = 0; i < 2; i++)
2549 seq_printf(m, "%02x ", buf[i]);
2550 seq_printf(m, "\n");
2551 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2552 seq_printf(m, "mst ctrl: ");
2553 for (i = 0; i < 1; i++)
2554 seq_printf(m, "%02x ", buf[i]);
2555 seq_printf(m, "\n");
2556
2557 bret = dump_dp_payload_table(mgr, buf);
2558 if (bret == true) {
2559 seq_printf(m, "payload table: ");
2560 for (i = 0; i < 63; i++)
2561 seq_printf(m, "%02x ", buf[i]);
2562 seq_printf(m, "\n");
2563 }
2564
2565 }
2566
2567 mutex_unlock(&mgr->lock);
2568
2569}
2570EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2571
2572static void drm_dp_tx_work(struct work_struct *work)
2573{
2574 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2575
2576 mutex_lock(&mgr->qlock);
2577 if (mgr->tx_down_in_progress)
2578 process_single_down_tx_qlock(mgr);
2579 mutex_unlock(&mgr->qlock);
2580}
2581
2582/**
2583 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2584 * @mgr: manager struct to initialise
2585 * @dev: device providing this structure - for i2c addition.
2586 * @aux: DP helper aux channel to talk to this device
2587 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2588 * @max_payloads: maximum number of payloads this GPU can source
2589 * @conn_base_id: the connector object ID the MST device is connected to.
2590 *
2591 * Return 0 for success, or negative error code on failure
2592 */
2593int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2594 struct device *dev, struct drm_dp_aux *aux,
2595 int max_dpcd_transaction_bytes,
2596 int max_payloads, int conn_base_id)
2597{
2598 mutex_init(&mgr->lock);
2599 mutex_init(&mgr->qlock);
2600 mutex_init(&mgr->payload_lock);
2601 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2602 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2603 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2604 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2605 init_waitqueue_head(&mgr->tx_waitq);
2606 mgr->dev = dev;
2607 mgr->aux = aux;
2608 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2609 mgr->max_payloads = max_payloads;
2610 mgr->conn_base_id = conn_base_id;
2611 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2612 if (!mgr->payloads)
2613 return -ENOMEM;
2614 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2615 if (!mgr->proposed_vcpis)
2616 return -ENOMEM;
2617 set_bit(0, &mgr->payload_mask);
2618 test_calc_pbn_mode();
2619 return 0;
2620}
2621EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2622
2623/**
2624 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2625 * @mgr: manager to destroy
2626 */
2627void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2628{
2629 mutex_lock(&mgr->payload_lock);
2630 kfree(mgr->payloads);
2631 mgr->payloads = NULL;
2632 kfree(mgr->proposed_vcpis);
2633 mgr->proposed_vcpis = NULL;
2634 mutex_unlock(&mgr->payload_lock);
2635 mgr->dev = NULL;
2636 mgr->aux = NULL;
2637}
2638EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2639
2640/* I2C device */
2641static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2642 int num)
2643{
2644 struct drm_dp_aux *aux = adapter->algo_data;
2645 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2646 struct drm_dp_mst_branch *mstb;
2647 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2648 unsigned int i;
2649 bool reading = false;
2650 struct drm_dp_sideband_msg_req_body msg;
2651 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2652 int ret;
2653
2654 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2655 if (!mstb)
2656 return -EREMOTEIO;
2657
2658 /* construct i2c msg */
2659 /* see if last msg is a read */
2660 if (msgs[num - 1].flags & I2C_M_RD)
2661 reading = true;
2662
2663 if (!reading) {
2664 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2665 ret = -EIO;
2666 goto out;
2667 }
2668
2669 msg.req_type = DP_REMOTE_I2C_READ;
2670 msg.u.i2c_read.num_transactions = num - 1;
2671 msg.u.i2c_read.port_number = port->port_num;
2672 for (i = 0; i < num - 1; i++) {
2673 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2674 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2675 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2676 }
2677 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2678 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2679
2680 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2681 if (!txmsg) {
2682 ret = -ENOMEM;
2683 goto out;
2684 }
2685
2686 txmsg->dst = mstb;
2687 drm_dp_encode_sideband_req(&msg, txmsg);
2688
2689 drm_dp_queue_down_tx(mgr, txmsg);
2690
2691 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2692 if (ret > 0) {
2693
2694 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2695 ret = -EREMOTEIO;
2696 goto out;
2697 }
2698 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2699 ret = -EIO;
2700 goto out;
2701 }
2702 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2703 ret = num;
2704 }
2705out:
2706 kfree(txmsg);
2707 drm_dp_put_mst_branch_device(mstb);
2708 return ret;
2709}
2710
2711static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2712{
2713 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2714 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2715 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2716 I2C_FUNC_10BIT_ADDR;
2717}
2718
2719static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2720 .functionality = drm_dp_mst_i2c_functionality,
2721 .master_xfer = drm_dp_mst_i2c_xfer,
2722};
2723
2724/**
2725 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2726 * @aux: DisplayPort AUX channel
2727 *
2728 * Returns 0 on success or a negative error code on failure.
2729 */
2730static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2731{
2732 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2733 aux->ddc.algo_data = aux;
2734 aux->ddc.retries = 3;
2735
2736 aux->ddc.class = I2C_CLASS_DDC;
2737 aux->ddc.owner = THIS_MODULE;
2738 aux->ddc.dev.parent = aux->dev;
2739 aux->ddc.dev.of_node = aux->dev->of_node;
2740
2741 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2742 sizeof(aux->ddc.name));
2743
2744 return i2c_add_adapter(&aux->ddc);
2745}
2746
2747/**
2748 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2749 * @aux: DisplayPort AUX channel
2750 */
2751static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2752{
2753 i2c_del_adapter(&aux->ddc);
2754}
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