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Merge tag 'mvebu-fixes-3.18-2' of git://git.infradead.org/linux-mvebu into fixes
[linux-block.git] / drivers / gpu / drm / drm_dp_mst_topology.c
CommitLineData
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,
1014 char *proppath)
1015{
1016 int i;
1017 char temp[8];
1018 snprintf(proppath, 255, "mst:%d", mstb->mgr->conn_base_id);
1019 for (i = 0; i < (mstb->lct - 1); i++) {
1020 int shift = (i % 2) ? 0 : 4;
1021 int port_num = mstb->rad[i / 2] >> shift;
1022 snprintf(temp, 8, "-%d", port_num);
1023 strncat(proppath, temp, 255);
1024 }
1025 snprintf(temp, 8, "-%d", port->port_num);
1026 strncat(proppath, temp, 255);
1027}
1028
1029static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1030 struct device *dev,
1031 struct drm_dp_link_addr_reply_port *port_msg)
1032{
1033 struct drm_dp_mst_port *port;
1034 bool ret;
1035 bool created = false;
1036 int old_pdt = 0;
1037 int old_ddps = 0;
1038 port = drm_dp_get_port(mstb, port_msg->port_number);
1039 if (!port) {
1040 port = kzalloc(sizeof(*port), GFP_KERNEL);
1041 if (!port)
1042 return;
1043 kref_init(&port->kref);
1044 port->parent = mstb;
1045 port->port_num = port_msg->port_number;
1046 port->mgr = mstb->mgr;
1047 port->aux.name = "DPMST";
1048 port->aux.dev = dev;
1049 created = true;
1050 } else {
1051 old_pdt = port->pdt;
1052 old_ddps = port->ddps;
1053 }
1054
1055 port->pdt = port_msg->peer_device_type;
1056 port->input = port_msg->input_port;
1057 port->mcs = port_msg->mcs;
1058 port->ddps = port_msg->ddps;
1059 port->ldps = port_msg->legacy_device_plug_status;
1060 port->dpcd_rev = port_msg->dpcd_revision;
1061 port->num_sdp_streams = port_msg->num_sdp_streams;
1062 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1063 memcpy(port->guid, port_msg->peer_guid, 16);
1064
1065 /* manage mstb port lists with mgr lock - take a reference
1066 for this list */
1067 if (created) {
1068 mutex_lock(&mstb->mgr->lock);
1069 kref_get(&port->kref);
1070 list_add(&port->next, &mstb->ports);
1071 mutex_unlock(&mstb->mgr->lock);
1072 }
1073
1074 if (old_ddps != port->ddps) {
1075 if (port->ddps) {
1076 drm_dp_check_port_guid(mstb, port);
1077 if (!port->input)
1078 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1079 } else {
1080 port->guid_valid = false;
1081 port->available_pbn = 0;
1082 }
1083 }
1084
1085 if (old_pdt != port->pdt && !port->input) {
1086 drm_dp_port_teardown_pdt(port, old_pdt);
1087
1088 ret = drm_dp_port_setup_pdt(port);
1089 if (ret == true) {
1090 drm_dp_send_link_address(mstb->mgr, port->mstb);
1091 port->mstb->link_address_sent = true;
1092 }
1093 }
1094
1095 if (created && !port->input) {
1096 char proppath[255];
1097 build_mst_prop_path(port, mstb, proppath);
1098 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1099 }
1100
1101 /* put reference to this port */
1102 drm_dp_put_port(port);
1103}
1104
1105static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1106 struct drm_dp_connection_status_notify *conn_stat)
1107{
1108 struct drm_dp_mst_port *port;
1109 int old_pdt;
1110 int old_ddps;
1111 bool dowork = false;
1112 port = drm_dp_get_port(mstb, conn_stat->port_number);
1113 if (!port)
1114 return;
1115
1116 old_ddps = port->ddps;
1117 old_pdt = port->pdt;
1118 port->pdt = conn_stat->peer_device_type;
1119 port->mcs = conn_stat->message_capability_status;
1120 port->ldps = conn_stat->legacy_device_plug_status;
1121 port->ddps = conn_stat->displayport_device_plug_status;
1122
1123 if (old_ddps != port->ddps) {
1124 if (port->ddps) {
1125 drm_dp_check_port_guid(mstb, port);
1126 dowork = true;
1127 } else {
1128 port->guid_valid = false;
1129 port->available_pbn = 0;
1130 }
1131 }
1132 if (old_pdt != port->pdt && !port->input) {
1133 drm_dp_port_teardown_pdt(port, old_pdt);
1134
1135 if (drm_dp_port_setup_pdt(port))
1136 dowork = true;
1137 }
1138
1139 drm_dp_put_port(port);
1140 if (dowork)
1141 queue_work(system_long_wq, &mstb->mgr->work);
1142
1143}
1144
1145static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1146 u8 lct, u8 *rad)
1147{
1148 struct drm_dp_mst_branch *mstb;
1149 struct drm_dp_mst_port *port;
1150 int i;
1151 /* find the port by iterating down */
1152 mstb = mgr->mst_primary;
1153
1154 for (i = 0; i < lct - 1; i++) {
1155 int shift = (i % 2) ? 0 : 4;
1156 int port_num = rad[i / 2] >> shift;
1157
1158 list_for_each_entry(port, &mstb->ports, next) {
1159 if (port->port_num == port_num) {
1160 if (!port->mstb) {
1161 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1162 return NULL;
1163 }
1164
1165 mstb = port->mstb;
1166 break;
1167 }
1168 }
1169 }
1170 kref_get(&mstb->kref);
1171 return mstb;
1172}
1173
1174static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1175 struct drm_dp_mst_branch *mstb)
1176{
1177 struct drm_dp_mst_port *port;
1178
1179 if (!mstb->link_address_sent) {
1180 drm_dp_send_link_address(mgr, mstb);
1181 mstb->link_address_sent = true;
1182 }
1183 list_for_each_entry(port, &mstb->ports, next) {
1184 if (port->input)
1185 continue;
1186
1187 if (!port->ddps)
1188 continue;
1189
1190 if (!port->available_pbn)
1191 drm_dp_send_enum_path_resources(mgr, mstb, port);
1192
1193 if (port->mstb)
1194 drm_dp_check_and_send_link_address(mgr, port->mstb);
1195 }
1196}
1197
1198static void drm_dp_mst_link_probe_work(struct work_struct *work)
1199{
1200 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1201
1202 drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
1203
1204}
1205
1206static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1207 u8 *guid)
1208{
1209 static u8 zero_guid[16];
1210
1211 if (!memcmp(guid, zero_guid, 16)) {
1212 u64 salt = get_jiffies_64();
1213 memcpy(&guid[0], &salt, sizeof(u64));
1214 memcpy(&guid[8], &salt, sizeof(u64));
1215 return false;
1216 }
1217 return true;
1218}
1219
1220#if 0
1221static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1222{
1223 struct drm_dp_sideband_msg_req_body req;
1224
1225 req.req_type = DP_REMOTE_DPCD_READ;
1226 req.u.dpcd_read.port_number = port_num;
1227 req.u.dpcd_read.dpcd_address = offset;
1228 req.u.dpcd_read.num_bytes = num_bytes;
1229 drm_dp_encode_sideband_req(&req, msg);
1230
1231 return 0;
1232}
1233#endif
1234
1235static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1236 bool up, u8 *msg, int len)
1237{
1238 int ret;
1239 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1240 int tosend, total, offset;
1241 int retries = 0;
1242
1243retry:
1244 total = len;
1245 offset = 0;
1246 do {
1247 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1248
1249 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1250 &msg[offset],
1251 tosend);
1252 if (ret != tosend) {
1253 if (ret == -EIO && retries < 5) {
1254 retries++;
1255 goto retry;
1256 }
1257 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1258 WARN(1, "fail\n");
1259
1260 return -EIO;
1261 }
1262 offset += tosend;
1263 total -= tosend;
1264 } while (total > 0);
1265 return 0;
1266}
1267
1268static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1269 struct drm_dp_sideband_msg_tx *txmsg)
1270{
1271 struct drm_dp_mst_branch *mstb = txmsg->dst;
1272
1273 /* both msg slots are full */
1274 if (txmsg->seqno == -1) {
1275 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1276 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1277 return -EAGAIN;
1278 }
1279 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1280 txmsg->seqno = mstb->last_seqno;
1281 mstb->last_seqno ^= 1;
1282 } else if (mstb->tx_slots[0] == NULL)
1283 txmsg->seqno = 0;
1284 else
1285 txmsg->seqno = 1;
1286 mstb->tx_slots[txmsg->seqno] = txmsg;
1287 }
1288 hdr->broadcast = 0;
1289 hdr->path_msg = txmsg->path_msg;
1290 hdr->lct = mstb->lct;
1291 hdr->lcr = mstb->lct - 1;
1292 if (mstb->lct > 1)
1293 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1294 hdr->seqno = txmsg->seqno;
1295 return 0;
1296}
1297/*
1298 * process a single block of the next message in the sideband queue
1299 */
1300static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1301 struct drm_dp_sideband_msg_tx *txmsg,
1302 bool up)
1303{
1304 u8 chunk[48];
1305 struct drm_dp_sideband_msg_hdr hdr;
1306 int len, space, idx, tosend;
1307 int ret;
1308
bf3719c0
DL		 1309 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1310
ad7f8a1f
DA		 1311 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1312 txmsg->seqno = -1;
1313 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1314 }
1315
1316 /* make hdr from dst mst - for replies use seqno
1317 otherwise assign one */
1318 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1319 if (ret < 0)
1320 return ret;
1321
1322 /* amount left to send in this message */
1323 len = txmsg->cur_len - txmsg->cur_offset;
1324
1325 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1326 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1327
1328 tosend = min(len, space);
1329 if (len == txmsg->cur_len)
1330 hdr.somt = 1;
1331 if (space >= len)
1332 hdr.eomt = 1;
1333
1334
1335 hdr.msg_len = tosend + 1;
1336 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1337 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1338 /* add crc at end */
1339 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1340 idx += tosend + 1;
1341
1342 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1343 if (ret) {
1344 DRM_DEBUG_KMS("sideband msg failed to send\n");
1345 return ret;
1346 }
1347
1348 txmsg->cur_offset += tosend;
1349 if (txmsg->cur_offset == txmsg->cur_len) {
1350 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1351 return 1;
1352 }
1353 return 0;
1354}
1355
1356/* must be called holding qlock */
1357static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1358{
1359 struct drm_dp_sideband_msg_tx *txmsg;
1360 int ret;
1361
1362 /* construct a chunk from the first msg in the tx_msg queue */
1363 if (list_empty(&mgr->tx_msg_downq)) {
1364 mgr->tx_down_in_progress = false;
1365 return;
1366 }
1367 mgr->tx_down_in_progress = true;
1368
1369 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1370 ret = process_single_tx_qlock(mgr, txmsg, false);
1371 if (ret == 1) {
1372 /* txmsg is sent it should be in the slots now */
1373 list_del(&txmsg->next);
1374 } else if (ret) {
1375 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1376 list_del(&txmsg->next);
1377 if (txmsg->seqno != -1)
1378 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1379 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1380 wake_up(&mgr->tx_waitq);
1381 }
1382 if (list_empty(&mgr->tx_msg_downq)) {
1383 mgr->tx_down_in_progress = false;
1384 return;
1385 }
1386}
1387
1388/* called holding qlock */
1389static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1390{
1391 struct drm_dp_sideband_msg_tx *txmsg;
1392 int ret;
1393
1394 /* construct a chunk from the first msg in the tx_msg queue */
1395 if (list_empty(&mgr->tx_msg_upq)) {
1396 mgr->tx_up_in_progress = false;
1397 return;
1398 }
1399
1400 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1401 ret = process_single_tx_qlock(mgr, txmsg, true);
1402 if (ret == 1) {
1403 /* up txmsgs aren't put in slots - so free after we send it */
1404 list_del(&txmsg->next);
1405 kfree(txmsg);
1406 } else if (ret)
1407 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1408 mgr->tx_up_in_progress = true;
1409}
1410
1411static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1412 struct drm_dp_sideband_msg_tx *txmsg)
1413{
1414 mutex_lock(&mgr->qlock);
1415 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1416 if (!mgr->tx_down_in_progress)
1417 process_single_down_tx_qlock(mgr);
1418 mutex_unlock(&mgr->qlock);
1419}
1420
1421static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1422 struct drm_dp_mst_branch *mstb)
1423{
1424 int len;
1425 struct drm_dp_sideband_msg_tx *txmsg;
1426 int ret;
1427
1428 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1429 if (!txmsg)
1430 return -ENOMEM;
1431
1432 txmsg->dst = mstb;
1433 len = build_link_address(txmsg);
1434
1435 drm_dp_queue_down_tx(mgr, txmsg);
1436
1437 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1438 if (ret > 0) {
1439 int i;
1440
1441 if (txmsg->reply.reply_type == 1)
1442 DRM_DEBUG_KMS("link address nak received\n");
1443 else {
1444 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1445 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1446 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,
1447 txmsg->reply.u.link_addr.ports[i].input_port,
1448 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1449 txmsg->reply.u.link_addr.ports[i].port_number,
1450 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1451 txmsg->reply.u.link_addr.ports[i].mcs,
1452 txmsg->reply.u.link_addr.ports[i].ddps,
1453 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1454 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1455 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1456 }
1457 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1458 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1459 }
1460 (*mgr->cbs->hotplug)(mgr);
1461 }
1462 } else
1463 DRM_DEBUG_KMS("link address failed %d\n", ret);
1464
1465 kfree(txmsg);
1466 return 0;
1467}
1468
1469static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1470 struct drm_dp_mst_branch *mstb,
1471 struct drm_dp_mst_port *port)
1472{
1473 int len;
1474 struct drm_dp_sideband_msg_tx *txmsg;
1475 int ret;
1476
1477 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1478 if (!txmsg)
1479 return -ENOMEM;
1480
1481 txmsg->dst = mstb;
1482 len = build_enum_path_resources(txmsg, port->port_num);
1483
1484 drm_dp_queue_down_tx(mgr, txmsg);
1485
1486 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1487 if (ret > 0) {
1488 if (txmsg->reply.reply_type == 1)
1489 DRM_DEBUG_KMS("enum path resources nak received\n");
1490 else {
1491 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1492 DRM_ERROR("got incorrect port in response\n");
1493 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,
1494 txmsg->reply.u.path_resources.avail_payload_bw_number);
1495 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1496 }
1497 }
1498
1499 kfree(txmsg);
1500 return 0;
1501}
1502
8fa6a425
TR		 1503static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1504 struct drm_dp_mst_port *port,
1505 int id,
1506 int pbn)
ad7f8a1f
DA		 1507{
1508 struct drm_dp_sideband_msg_tx *txmsg;
1509 struct drm_dp_mst_branch *mstb;
1510 int len, ret;
1511
1512 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1513 if (!mstb)
1514 return -EINVAL;
1515
1516 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1517 if (!txmsg) {
1518 ret = -ENOMEM;
1519 goto fail_put;
1520 }
1521
1522 txmsg->dst = mstb;
1523 len = build_allocate_payload(txmsg, port->port_num,
1524 id,
1525 pbn);
1526
1527 drm_dp_queue_down_tx(mgr, txmsg);
1528
1529 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1530 if (ret > 0) {
1531 if (txmsg->reply.reply_type == 1) {
1532 ret = -EINVAL;
1533 } else
1534 ret = 0;
1535 }
1536 kfree(txmsg);
1537fail_put:
1538 drm_dp_put_mst_branch_device(mstb);
1539 return ret;
1540}
1541
1542static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1543 int id,
1544 struct drm_dp_payload *payload)
1545{
1546 int ret;
1547
1548 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1549 if (ret < 0) {
1550 payload->payload_state = 0;
1551 return ret;
1552 }
1553 payload->payload_state = DP_PAYLOAD_LOCAL;
1554 return 0;
1555}
1556
8fa6a425
TR		 1557static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1558 struct drm_dp_mst_port *port,
1559 int id,
1560 struct drm_dp_payload *payload)
ad7f8a1f
DA		 1561{
1562 int ret;
1563 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1564 if (ret < 0)
1565 return ret;
1566 payload->payload_state = DP_PAYLOAD_REMOTE;
1567 return ret;
1568}
1569
8fa6a425
TR		 1570static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1571 struct drm_dp_mst_port *port,
1572 int id,
1573 struct drm_dp_payload *payload)
ad7f8a1f
DA		 1574{
1575 DRM_DEBUG_KMS("\n");
1576 /* its okay for these to fail */
1577 if (port) {
1578 drm_dp_payload_send_msg(mgr, port, id, 0);
1579 }
1580
1581 drm_dp_dpcd_write_payload(mgr, id, payload);
dfda0df3 1582 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL;
ad7f8a1f
DA		 1583 return 0;
1584}
1585
8fa6a425
TR		 1586static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1587 int id,
1588 struct drm_dp_payload *payload)
ad7f8a1f
DA		 1589{
1590 payload->payload_state = 0;
1591 return 0;
1592}
1593
1594/**
1595 * drm_dp_update_payload_part1() - Execute payload update part 1
1596 * @mgr: manager to use.
1597 *
1598 * This iterates over all proposed virtual channels, and tries to
1599 * allocate space in the link for them. For 0->slots transitions,
1600 * this step just writes the VCPI to the MST device. For slots->0
1601 * transitions, this writes the updated VCPIs and removes the
1602 * remote VC payloads.
1603 *
1604 * after calling this the driver should generate ACT and payload
1605 * packets.
1606 */
1607int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1608{
dfda0df3 1609 int i, j;
ad7f8a1f
DA		 1610 int cur_slots = 1;
1611 struct drm_dp_payload req_payload;
1612 struct drm_dp_mst_port *port;
1613
1614 mutex_lock(&mgr->payload_lock);
1615 for (i = 0; i < mgr->max_payloads; i++) {
1616 /* solve the current payloads - compare to the hw ones
1617 - update the hw view */
1618 req_payload.start_slot = cur_slots;
1619 if (mgr->proposed_vcpis[i]) {
1620 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1621 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1622 } else {
1623 port = NULL;
1624 req_payload.num_slots = 0;
1625 }
dfda0df3
DA		 1626
1627 if (mgr->payloads[i].start_slot != req_payload.start_slot) {
1628 mgr->payloads[i].start_slot = req_payload.start_slot;
1629 }
ad7f8a1f 1630 /* work out what is required to happen with this payload */
dfda0df3 1631 if (mgr->payloads[i].num_slots != req_payload.num_slots) {
ad7f8a1f
DA		 1632
1633 /* need to push an update for this payload */
1634 if (req_payload.num_slots) {
dfda0df3 1635 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload);
ad7f8a1f
DA		 1636 mgr->payloads[i].num_slots = req_payload.num_slots;
1637 } else if (mgr->payloads[i].num_slots) {
1638 mgr->payloads[i].num_slots = 0;
dfda0df3 1639 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]);
ad7f8a1f 1640 req_payload.payload_state = mgr->payloads[i].payload_state;
dfda0df3
DA		 1641 mgr->payloads[i].start_slot = 0;
1642 }
ad7f8a1f
DA		 1643 mgr->payloads[i].payload_state = req_payload.payload_state;
1644 }
1645 cur_slots += req_payload.num_slots;
1646 }
dfda0df3
DA		 1647
1648 for (i = 0; i < mgr->max_payloads; i++) {
1649 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1650 DRM_DEBUG_KMS("removing payload %d\n", i);
1651 for (j = i; j < mgr->max_payloads - 1; j++) {
1652 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload));
1653 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1];
1654 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) {
1655 set_bit(j + 1, &mgr->payload_mask);
1656 } else {
1657 clear_bit(j + 1, &mgr->payload_mask);
1658 }
1659 }
1660 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload));
1661 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL;
1662 clear_bit(mgr->max_payloads, &mgr->payload_mask);
1663
1664 }
1665 }
ad7f8a1f
DA		 1666 mutex_unlock(&mgr->payload_lock);
1667
1668 return 0;
1669}
1670EXPORT_SYMBOL(drm_dp_update_payload_part1);
1671
1672/**
1673 * drm_dp_update_payload_part2() - Execute payload update part 2
1674 * @mgr: manager to use.
1675 *
1676 * This iterates over all proposed virtual channels, and tries to
1677 * allocate space in the link for them. For 0->slots transitions,
1678 * this step writes the remote VC payload commands. For slots->0
1679 * this just resets some internal state.
1680 */
1681int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1682{
1683 struct drm_dp_mst_port *port;
1684 int i;
7389ad4b 1685 int ret = 0;
ad7f8a1f
DA		 1686 mutex_lock(&mgr->payload_lock);
1687 for (i = 0; i < mgr->max_payloads; i++) {
1688
1689 if (!mgr->proposed_vcpis[i])
1690 continue;
1691
1692 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1693
1694 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1695 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
dfda0df3 1696 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
ad7f8a1f 1697 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
dfda0df3 1698 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
ad7f8a1f
DA		 1699 }
1700 if (ret) {
1701 mutex_unlock(&mgr->payload_lock);
1702 return ret;
1703 }
1704 }
1705 mutex_unlock(&mgr->payload_lock);
1706 return 0;
1707}
1708EXPORT_SYMBOL(drm_dp_update_payload_part2);
1709
1710#if 0 /* unused as of yet */
1711static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1712 struct drm_dp_mst_port *port,
1713 int offset, int size)
1714{
1715 int len;
1716 struct drm_dp_sideband_msg_tx *txmsg;
1717
1718 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1719 if (!txmsg)
1720 return -ENOMEM;
1721
1722 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1723 txmsg->dst = port->parent;
1724
1725 drm_dp_queue_down_tx(mgr, txmsg);
1726
1727 return 0;
1728}
1729#endif
1730
1731static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1732 struct drm_dp_mst_port *port,
1733 int offset, int size, u8 *bytes)
1734{
1735 int len;
1736 int ret;
1737 struct drm_dp_sideband_msg_tx *txmsg;
1738 struct drm_dp_mst_branch *mstb;
1739
1740 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1741 if (!mstb)
1742 return -EINVAL;
1743
1744 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1745 if (!txmsg) {
1746 ret = -ENOMEM;
1747 goto fail_put;
1748 }
1749
1750 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1751 txmsg->dst = mstb;
1752
1753 drm_dp_queue_down_tx(mgr, txmsg);
1754
1755 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1756 if (ret > 0) {
1757 if (txmsg->reply.reply_type == 1) {
1758 ret = -EINVAL;
1759 } else
1760 ret = 0;
1761 }
1762 kfree(txmsg);
1763fail_put:
1764 drm_dp_put_mst_branch_device(mstb);
1765 return ret;
1766}
1767
1768static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1769{
1770 struct drm_dp_sideband_msg_reply_body reply;
1771
1772 reply.reply_type = 1;
1773 reply.req_type = req_type;
1774 drm_dp_encode_sideband_reply(&reply, msg);
1775 return 0;
1776}
1777
1778static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1779 struct drm_dp_mst_branch *mstb,
1780 int req_type, int seqno, bool broadcast)
1781{
1782 struct drm_dp_sideband_msg_tx *txmsg;
1783
1784 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1785 if (!txmsg)
1786 return -ENOMEM;
1787
1788 txmsg->dst = mstb;
1789 txmsg->seqno = seqno;
1790 drm_dp_encode_up_ack_reply(txmsg, req_type);
1791
1792 mutex_lock(&mgr->qlock);
1793 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1794 if (!mgr->tx_up_in_progress) {
1795 process_single_up_tx_qlock(mgr);
1796 }
1797 mutex_unlock(&mgr->qlock);
1798 return 0;
1799}
1800
1801static int drm_dp_get_vc_payload_bw(int dp_link_bw, int dp_link_count)
1802{
1803 switch (dp_link_bw) {
1804 case DP_LINK_BW_1_62:
1805 return 3 * dp_link_count;
1806 case DP_LINK_BW_2_7:
1807 return 5 * dp_link_count;
1808 case DP_LINK_BW_5_4:
1809 return 10 * dp_link_count;
1810 }
c11cda52 1811 BUG();
ad7f8a1f
DA		 1812}
1813
1814/**
1815 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1816 * @mgr: manager to set state for
1817 * @mst_state: true to enable MST on this connector - false to disable.
1818 *
1819 * This is called by the driver when it detects an MST capable device plugged
1820 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1821 */
1822int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1823{
1824 int ret = 0;
1825 struct drm_dp_mst_branch *mstb = NULL;
1826
1827 mutex_lock(&mgr->lock);
1828 if (mst_state == mgr->mst_state)
1829 goto out_unlock;
1830
1831 mgr->mst_state = mst_state;
1832 /* set the device into MST mode */
1833 if (mst_state) {
1834 WARN_ON(mgr->mst_primary);
1835
1836 /* get dpcd info */
1837 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1838 if (ret != DP_RECEIVER_CAP_SIZE) {
1839 DRM_DEBUG_KMS("failed to read DPCD\n");
1840 goto out_unlock;
1841 }
1842
1843 mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1], mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK);
1844 mgr->total_pbn = 2560;
1845 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1846 mgr->avail_slots = mgr->total_slots;
1847
1848 /* add initial branch device at LCT 1 */
1849 mstb = drm_dp_add_mst_branch_device(1, NULL);
1850 if (mstb == NULL) {
1851 ret = -ENOMEM;
1852 goto out_unlock;
1853 }
1854 mstb->mgr = mgr;
1855
1856 /* give this the main reference */
1857 mgr->mst_primary = mstb;
1858 kref_get(&mgr->mst_primary->kref);
1859
1860 {
1861 struct drm_dp_payload reset_pay;
1862 reset_pay.start_slot = 0;
1863 reset_pay.num_slots = 0x3f;
1864 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1865 }
1866
1867 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1868 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1869 if (ret < 0) {
1870 goto out_unlock;
1871 }
1872
1873
1874 /* sort out guid */
1875 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1876 if (ret != 16) {
1877 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1878 goto out_unlock;
1879 }
1880
1881 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1882 if (!mgr->guid_valid) {
1883 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1884 mgr->guid_valid = true;
1885 }
1886
1887 queue_work(system_long_wq, &mgr->work);
1888
1889 ret = 0;
1890 } else {
1891 /* disable MST on the device */
1892 mstb = mgr->mst_primary;
1893 mgr->mst_primary = NULL;
1894 /* this can fail if the device is gone */
1895 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1896 ret = 0;
1897 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1898 mgr->payload_mask = 0;
1899 set_bit(0, &mgr->payload_mask);
dfda0df3 1900 mgr->vcpi_mask = 0;
ad7f8a1f
DA		 1901 }
1902
1903out_unlock:
1904 mutex_unlock(&mgr->lock);
1905 if (mstb)
1906 drm_dp_put_mst_branch_device(mstb);
1907 return ret;
1908
1909}
1910EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1911
1912/**
1913 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1914 * @mgr: manager to suspend
1915 *
1916 * This function tells the MST device that we can't handle UP messages
1917 * anymore. This should stop it from sending any since we are suspended.
1918 */
1919void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1920{
1921 mutex_lock(&mgr->lock);
1922 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1923 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1924 mutex_unlock(&mgr->lock);
1925}
1926EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1927
1928/**
1929 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1930 * @mgr: manager to resume
1931 *
1932 * This will fetch DPCD and see if the device is still there,
1933 * if it is, it will rewrite the MSTM control bits, and return.
1934 *
1935 * if the device fails this returns -1, and the driver should do
1936 * a full MST reprobe, in case we were undocked.
1937 */
1938int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1939{
1940 int ret = 0;
1941
1942 mutex_lock(&mgr->lock);
1943
1944 if (mgr->mst_primary) {
1945 int sret;
1946 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1947 if (sret != DP_RECEIVER_CAP_SIZE) {
1948 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1949 ret = -1;
1950 goto out_unlock;
1951 }
1952
1953 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1954 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1955 if (ret < 0) {
1956 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1957 ret = -1;
1958 goto out_unlock;
1959 }
1960 ret = 0;
1961 } else
1962 ret = -1;
1963
1964out_unlock:
1965 mutex_unlock(&mgr->lock);
1966 return ret;
1967}
1968EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
1969
1970static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
1971{
1972 int len;
1973 u8 replyblock[32];
1974 int replylen, origlen, curreply;
1975 int ret;
1976 struct drm_dp_sideband_msg_rx *msg;
1977 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
1978 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
1979
1980 len = min(mgr->max_dpcd_transaction_bytes, 16);
1981 ret = drm_dp_dpcd_read(mgr->aux, basereg,
1982 replyblock, len);
1983 if (ret != len) {
1984 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
1985 return;
1986 }
1987 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
1988 if (!ret) {
1989 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
1990 return;
1991 }
1992 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
1993
1994 origlen = replylen;
1995 replylen -= len;
1996 curreply = len;
1997 while (replylen > 0) {
1998 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
1999 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
2000 replyblock, len);
2001 if (ret != len) {
2002 DRM_DEBUG_KMS("failed to read a chunk\n");
2003 }
2004 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
2005 if (ret == false)
2006 DRM_DEBUG_KMS("failed to build sideband msg\n");
2007 curreply += len;
2008 replylen -= len;
2009 }
2010}
2011
2012static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
2013{
2014 int ret = 0;
2015
2016 drm_dp_get_one_sb_msg(mgr, false);
2017
2018 if (mgr->down_rep_recv.have_eomt) {
2019 struct drm_dp_sideband_msg_tx *txmsg;
2020 struct drm_dp_mst_branch *mstb;
2021 int slot = -1;
2022 mstb = drm_dp_get_mst_branch_device(mgr,
2023 mgr->down_rep_recv.initial_hdr.lct,
2024 mgr->down_rep_recv.initial_hdr.rad);
2025
2026 if (!mstb) {
2027 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
2028 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2029 return 0;
2030 }
2031
2032 /* find the message */
2033 slot = mgr->down_rep_recv.initial_hdr.seqno;
2034 mutex_lock(&mgr->qlock);
2035 txmsg = mstb->tx_slots[slot];
2036 /* remove from slots */
2037 mutex_unlock(&mgr->qlock);
2038
2039 if (!txmsg) {
2040 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2041 mstb,
2042 mgr->down_rep_recv.initial_hdr.seqno,
2043 mgr->down_rep_recv.initial_hdr.lct,
2044 mgr->down_rep_recv.initial_hdr.rad[0],
2045 mgr->down_rep_recv.msg[0]);
2046 drm_dp_put_mst_branch_device(mstb);
2047 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2048 return 0;
2049 }
2050
2051 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2052 if (txmsg->reply.reply_type == 1) {
2053 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);
2054 }
2055
2056 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2057 drm_dp_put_mst_branch_device(mstb);
2058
2059 mutex_lock(&mgr->qlock);
2060 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2061 mstb->tx_slots[slot] = NULL;
2062 mutex_unlock(&mgr->qlock);
2063
2064 wake_up(&mgr->tx_waitq);
2065 }
2066 return ret;
2067}
2068
2069static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2070{
2071 int ret = 0;
2072 drm_dp_get_one_sb_msg(mgr, true);
2073
2074 if (mgr->up_req_recv.have_eomt) {
2075 struct drm_dp_sideband_msg_req_body msg;
2076 struct drm_dp_mst_branch *mstb;
2077 bool seqno;
2078 mstb = drm_dp_get_mst_branch_device(mgr,
2079 mgr->up_req_recv.initial_hdr.lct,
2080 mgr->up_req_recv.initial_hdr.rad);
2081 if (!mstb) {
2082 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2083 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2084 return 0;
2085 }
2086
2087 seqno = mgr->up_req_recv.initial_hdr.seqno;
2088 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2089
2090 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2091 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2092 drm_dp_update_port(mstb, &msg.u.conn_stat);
2093 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);
2094 (*mgr->cbs->hotplug)(mgr);
2095
2096 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2097 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2098 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2099 }
2100
2101 drm_dp_put_mst_branch_device(mstb);
2102 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2103 }
2104 return ret;
2105}
2106
2107/**
2108 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2109 * @mgr: manager to notify irq for.
2110 * @esi: 4 bytes from SINK_COUNT_ESI
295ee853 2111 * @handled: whether the hpd interrupt was consumed or not
ad7f8a1f
DA		 2112 *
2113 * This should be called from the driver when it detects a short IRQ,
2114 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2115 * topology manager will process the sideband messages received as a result
2116 * of this.
2117 */
2118int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2119{
2120 int ret = 0;
2121 int sc;
2122 *handled = false;
2123 sc = esi[0] & 0x3f;
2124
2125 if (sc != mgr->sink_count) {
2126 mgr->sink_count = sc;
2127 *handled = true;
2128 }
2129
2130 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2131 ret = drm_dp_mst_handle_down_rep(mgr);
2132 *handled = true;
2133 }
2134
2135 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2136 ret |= drm_dp_mst_handle_up_req(mgr);
2137 *handled = true;
2138 }
2139
2140 drm_dp_mst_kick_tx(mgr);
2141 return ret;
2142}
2143EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2144
2145/**
2146 * drm_dp_mst_detect_port() - get connection status for an MST port
2147 * @mgr: manager for this port
2148 * @port: unverified pointer to a port
2149 *
2150 * This returns the current connection state for a port. It validates the
2151 * port pointer still exists so the caller doesn't require a reference
2152 */
2153enum drm_connector_status drm_dp_mst_detect_port(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2154{
2155 enum drm_connector_status status = connector_status_disconnected;
2156
2157 /* we need to search for the port in the mgr in case its gone */
2158 port = drm_dp_get_validated_port_ref(mgr, port);
2159 if (!port)
2160 return connector_status_disconnected;
2161
2162 if (!port->ddps)
2163 goto out;
2164
2165 switch (port->pdt) {
2166 case DP_PEER_DEVICE_NONE:
2167 case DP_PEER_DEVICE_MST_BRANCHING:
2168 break;
2169
2170 case DP_PEER_DEVICE_SST_SINK:
2171 status = connector_status_connected;
2172 break;
2173 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2174 if (port->ldps)
2175 status = connector_status_connected;
2176 break;
2177 }
2178out:
2179 drm_dp_put_port(port);
2180 return status;
2181}
2182EXPORT_SYMBOL(drm_dp_mst_detect_port);
2183
2184/**
2185 * drm_dp_mst_get_edid() - get EDID for an MST port
2186 * @connector: toplevel connector to get EDID for
2187 * @mgr: manager for this port
2188 * @port: unverified pointer to a port.
2189 *
2190 * This returns an EDID for the port connected to a connector,
2191 * It validates the pointer still exists so the caller doesn't require a
2192 * reference.
2193 */
2194struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2195{
2196 struct edid *edid = NULL;
2197
2198 /* we need to search for the port in the mgr in case its gone */
2199 port = drm_dp_get_validated_port_ref(mgr, port);
2200 if (!port)
2201 return NULL;
2202
2203 edid = drm_get_edid(connector, &port->aux.ddc);
2204 drm_dp_put_port(port);
2205 return edid;
2206}
2207EXPORT_SYMBOL(drm_dp_mst_get_edid);
2208
2209/**
2210 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2211 * @mgr: manager to use
2212 * @pbn: payload bandwidth to convert into slots.
2213 */
2214int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2215 int pbn)
2216{
2217 int num_slots;
2218
2219 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2220
2221 if (num_slots > mgr->avail_slots)
2222 return -ENOSPC;
2223 return num_slots;
2224}
2225EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2226
2227static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2228 struct drm_dp_vcpi *vcpi, int pbn)
2229{
2230 int num_slots;
2231 int ret;
2232
2233 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2234
2235 if (num_slots > mgr->avail_slots)
2236 return -ENOSPC;
2237
2238 vcpi->pbn = pbn;
2239 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2240 vcpi->num_slots = num_slots;
2241
2242 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2243 if (ret < 0)
2244 return ret;
2245 return 0;
2246}
2247
2248/**
2249 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2250 * @mgr: manager for this port
2251 * @port: port to allocate a virtual channel for.
2252 * @pbn: payload bandwidth number to request
2253 * @slots: returned number of slots for this PBN.
2254 */
2255bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2256{
2257 int ret;
2258
2259 port = drm_dp_get_validated_port_ref(mgr, port);
2260 if (!port)
2261 return false;
2262
2263 if (port->vcpi.vcpi > 0) {
2264 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2265 if (pbn == port->vcpi.pbn) {
2266 *slots = port->vcpi.num_slots;
2267 return true;
2268 }
2269 }
2270
2271 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2272 if (ret) {
2273 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2274 goto out;
2275 }
2276 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2277 *slots = port->vcpi.num_slots;
2278
2279 drm_dp_put_port(port);
2280 return true;
2281out:
2282 return false;
2283}
2284EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2285
2286/**
2287 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2288 * @mgr: manager for this port
2289 * @port: unverified pointer to a port.
2290 *
2291 * This just resets the number of slots for the ports VCPI for later programming.
2292 */
2293void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2294{
2295 port = drm_dp_get_validated_port_ref(mgr, port);
2296 if (!port)
2297 return;
2298 port->vcpi.num_slots = 0;
2299 drm_dp_put_port(port);
2300}
2301EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2302
2303/**
2304 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2305 * @mgr: manager for this port
2306 * @port: unverified port to deallocate vcpi for
2307 */
2308void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2309{
2310 port = drm_dp_get_validated_port_ref(mgr, port);
2311 if (!port)
2312 return;
2313
2314 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2315 port->vcpi.num_slots = 0;
2316 port->vcpi.pbn = 0;
2317 port->vcpi.aligned_pbn = 0;
2318 port->vcpi.vcpi = 0;
2319 drm_dp_put_port(port);
2320}
2321EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2322
2323static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2324 int id, struct drm_dp_payload *payload)
2325{
2326 u8 payload_alloc[3], status;
2327 int ret;
2328 int retries = 0;
2329
2330 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2331 DP_PAYLOAD_TABLE_UPDATED);
2332
2333 payload_alloc[0] = id;
2334 payload_alloc[1] = payload->start_slot;
2335 payload_alloc[2] = payload->num_slots;
2336
2337 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2338 if (ret != 3) {
2339 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2340 goto fail;
2341 }
2342
2343retry:
2344 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2345 if (ret < 0) {
2346 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2347 goto fail;
2348 }
2349
2350 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2351 retries++;
2352 if (retries < 20) {
2353 usleep_range(10000, 20000);
2354 goto retry;
2355 }
2356 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2357 ret = -EINVAL;
2358 goto fail;
2359 }
2360 ret = 0;
2361fail:
2362 return ret;
2363}
2364
2365
2366/**
2367 * drm_dp_check_act_status() - Check ACT handled status.
2368 * @mgr: manager to use
2369 *
2370 * Check the payload status bits in the DPCD for ACT handled completion.
2371 */
2372int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2373{
2374 u8 status;
2375 int ret;
2376 int count = 0;
2377
2378 do {
2379 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2380
2381 if (ret < 0) {
2382 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2383 goto fail;
2384 }
2385
2386 if (status & DP_PAYLOAD_ACT_HANDLED)
2387 break;
2388 count++;
2389 udelay(100);
2390
2391 } while (count < 30);
2392
2393 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2394 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2395 ret = -EINVAL;
2396 goto fail;
2397 }
2398 return 0;
2399fail:
2400 return ret;
2401}
2402EXPORT_SYMBOL(drm_dp_check_act_status);
2403
2404/**
2405 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2406 * @clock: dot clock for the mode
2407 * @bpp: bpp for the mode.
2408 *
2409 * This uses the formula in the spec to calculate the PBN value for a mode.
2410 */
2411int drm_dp_calc_pbn_mode(int clock, int bpp)
2412{
2413 fixed20_12 pix_bw;
2414 fixed20_12 fbpp;
2415 fixed20_12 result;
2416 fixed20_12 margin, tmp;
2417 u32 res;
2418
2419 pix_bw.full = dfixed_const(clock);
2420 fbpp.full = dfixed_const(bpp);
2421 tmp.full = dfixed_const(8);
2422 fbpp.full = dfixed_div(fbpp, tmp);
2423
2424 result.full = dfixed_mul(pix_bw, fbpp);
2425 margin.full = dfixed_const(54);
2426 tmp.full = dfixed_const(64);
2427 margin.full = dfixed_div(margin, tmp);
2428 result.full = dfixed_div(result, margin);
2429
2430 margin.full = dfixed_const(1006);
2431 tmp.full = dfixed_const(1000);
2432 margin.full = dfixed_div(margin, tmp);
2433 result.full = dfixed_mul(result, margin);
2434
2435 result.full = dfixed_div(result, tmp);
2436 result.full = dfixed_ceil(result);
2437 res = dfixed_trunc(result);
2438 return res;
2439}
2440EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2441
2442static int test_calc_pbn_mode(void)
2443{
2444 int ret;
2445 ret = drm_dp_calc_pbn_mode(154000, 30);
2446 if (ret != 689)
2447 return -EINVAL;
2448 ret = drm_dp_calc_pbn_mode(234000, 30);
2449 if (ret != 1047)
2450 return -EINVAL;
2451 return 0;
2452}
2453
2454/* we want to kick the TX after we've ack the up/down IRQs. */
2455static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2456{
2457 queue_work(system_long_wq, &mgr->tx_work);
2458}
2459
2460static void drm_dp_mst_dump_mstb(struct seq_file *m,
2461 struct drm_dp_mst_branch *mstb)
2462{
2463 struct drm_dp_mst_port *port;
2464 int tabs = mstb->lct;
2465 char prefix[10];
2466 int i;
2467
2468 for (i = 0; i < tabs; i++)
2469 prefix[i] = '\t';
2470 prefix[i] = '\0';
2471
2472 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2473 list_for_each_entry(port, &mstb->ports, next) {
2474 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2475 if (port->mstb)
2476 drm_dp_mst_dump_mstb(m, port->mstb);
2477 }
2478}
2479
2480static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2481 char *buf)
2482{
2483 int ret;
2484 int i;
2485 for (i = 0; i < 4; i++) {
2486 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2487 if (ret != 16)
2488 break;
2489 }
2490 if (i == 4)
2491 return true;
2492 return false;
2493}
2494
2495/**
2496 * drm_dp_mst_dump_topology(): dump topology to seq file.
2497 * @m: seq_file to dump output to
2498 * @mgr: manager to dump current topology for.
2499 *
2500 * helper to dump MST topology to a seq file for debugfs.
2501 */
2502void drm_dp_mst_dump_topology(struct seq_file *m,
2503 struct drm_dp_mst_topology_mgr *mgr)
2504{
2505 int i;
2506 struct drm_dp_mst_port *port;
2507 mutex_lock(&mgr->lock);
2508 if (mgr->mst_primary)
2509 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2510
2511 /* dump VCPIs */
2512 mutex_unlock(&mgr->lock);
2513
2514 mutex_lock(&mgr->payload_lock);
dfda0df3 2515 seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask);
ad7f8a1f
DA		 2516
2517 for (i = 0; i < mgr->max_payloads; i++) {
2518 if (mgr->proposed_vcpis[i]) {
2519 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2520 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2521 } else
2522 seq_printf(m, "vcpi %d:unsed\n", i);
2523 }
2524 for (i = 0; i < mgr->max_payloads; i++) {
2525 seq_printf(m, "payload %d: %d, %d, %d\n",
2526 i,
2527 mgr->payloads[i].payload_state,
2528 mgr->payloads[i].start_slot,
2529 mgr->payloads[i].num_slots);
2530
2531
2532 }
2533 mutex_unlock(&mgr->payload_lock);
2534
2535 mutex_lock(&mgr->lock);
2536 if (mgr->mst_primary) {
2537 u8 buf[64];
2538 bool bret;
2539 int ret;
2540 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2541 seq_printf(m, "dpcd: ");
2542 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2543 seq_printf(m, "%02x ", buf[i]);
2544 seq_printf(m, "\n");
2545 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2546 seq_printf(m, "faux/mst: ");
2547 for (i = 0; i < 2; i++)
2548 seq_printf(m, "%02x ", buf[i]);
2549 seq_printf(m, "\n");
2550 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2551 seq_printf(m, "mst ctrl: ");
2552 for (i = 0; i < 1; i++)
2553 seq_printf(m, "%02x ", buf[i]);
2554 seq_printf(m, "\n");
2555
2556 bret = dump_dp_payload_table(mgr, buf);
2557 if (bret == true) {
2558 seq_printf(m, "payload table: ");
2559 for (i = 0; i < 63; i++)
2560 seq_printf(m, "%02x ", buf[i]);
2561 seq_printf(m, "\n");
2562 }
2563
2564 }
2565
2566 mutex_unlock(&mgr->lock);
2567
2568}
2569EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2570
2571static void drm_dp_tx_work(struct work_struct *work)
2572{
2573 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2574
2575 mutex_lock(&mgr->qlock);
2576 if (mgr->tx_down_in_progress)
2577 process_single_down_tx_qlock(mgr);
2578 mutex_unlock(&mgr->qlock);
2579}
2580
2581/**
2582 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2583 * @mgr: manager struct to initialise
2584 * @dev: device providing this structure - for i2c addition.
2585 * @aux: DP helper aux channel to talk to this device
2586 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2587 * @max_payloads: maximum number of payloads this GPU can source
2588 * @conn_base_id: the connector object ID the MST device is connected to.
2589 *
2590 * Return 0 for success, or negative error code on failure
2591 */
2592int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2593 struct device *dev, struct drm_dp_aux *aux,
2594 int max_dpcd_transaction_bytes,
2595 int max_payloads, int conn_base_id)
2596{
2597 mutex_init(&mgr->lock);
2598 mutex_init(&mgr->qlock);
2599 mutex_init(&mgr->payload_lock);
2600 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2601 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2602 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2603 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2604 init_waitqueue_head(&mgr->tx_waitq);
2605 mgr->dev = dev;
2606 mgr->aux = aux;
2607 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2608 mgr->max_payloads = max_payloads;
2609 mgr->conn_base_id = conn_base_id;
2610 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2611 if (!mgr->payloads)
2612 return -ENOMEM;
2613 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2614 if (!mgr->proposed_vcpis)
2615 return -ENOMEM;
2616 set_bit(0, &mgr->payload_mask);
2617 test_calc_pbn_mode();
2618 return 0;
2619}
2620EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2621
2622/**
2623 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2624 * @mgr: manager to destroy
2625 */
2626void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2627{
2628 mutex_lock(&mgr->payload_lock);
2629 kfree(mgr->payloads);
2630 mgr->payloads = NULL;
2631 kfree(mgr->proposed_vcpis);
2632 mgr->proposed_vcpis = NULL;
2633 mutex_unlock(&mgr->payload_lock);
2634 mgr->dev = NULL;
2635 mgr->aux = NULL;
2636}
2637EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2638
2639/* I2C device */
2640static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2641 int num)
2642{
2643 struct drm_dp_aux *aux = adapter->algo_data;
2644 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2645 struct drm_dp_mst_branch *mstb;
2646 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2647 unsigned int i;
2648 bool reading = false;
2649 struct drm_dp_sideband_msg_req_body msg;
2650 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2651 int ret;
2652
2653 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2654 if (!mstb)
2655 return -EREMOTEIO;
2656
2657 /* construct i2c msg */
2658 /* see if last msg is a read */
2659 if (msgs[num - 1].flags & I2C_M_RD)
2660 reading = true;
2661
2662 if (!reading) {
2663 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2664 ret = -EIO;
2665 goto out;
2666 }
2667
2668 msg.req_type = DP_REMOTE_I2C_READ;
2669 msg.u.i2c_read.num_transactions = num - 1;
2670 msg.u.i2c_read.port_number = port->port_num;
2671 for (i = 0; i < num - 1; i++) {
2672 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2673 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2674 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2675 }
2676 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2677 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2678
2679 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2680 if (!txmsg) {
2681 ret = -ENOMEM;
2682 goto out;
2683 }
2684
2685 txmsg->dst = mstb;
2686 drm_dp_encode_sideband_req(&msg, txmsg);
2687
2688 drm_dp_queue_down_tx(mgr, txmsg);
2689
2690 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2691 if (ret > 0) {
2692
2693 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2694 ret = -EREMOTEIO;
2695 goto out;
2696 }
2697 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2698 ret = -EIO;
2699 goto out;
2700 }
2701 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2702 ret = num;
2703 }
2704out:
2705 kfree(txmsg);
2706 drm_dp_put_mst_branch_device(mstb);
2707 return ret;
2708}
2709
2710static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2711{
2712 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2713 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2714 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2715 I2C_FUNC_10BIT_ADDR;
2716}
2717
2718static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2719 .functionality = drm_dp_mst_i2c_functionality,
2720 .master_xfer = drm_dp_mst_i2c_xfer,
2721};
2722
2723/**
2724 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2725 * @aux: DisplayPort AUX channel
2726 *
2727 * Returns 0 on success or a negative error code on failure.
2728 */
2729static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2730{
2731 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2732 aux->ddc.algo_data = aux;
2733 aux->ddc.retries = 3;
2734
2735 aux->ddc.class = I2C_CLASS_DDC;
2736 aux->ddc.owner = THIS_MODULE;
2737 aux->ddc.dev.parent = aux->dev;
2738 aux->ddc.dev.of_node = aux->dev->of_node;
2739
2740 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2741 sizeof(aux->ddc.name));
2742
2743 return i2c_add_adapter(&aux->ddc);
2744}
2745
2746/**
2747 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2748 * @aux: DisplayPort AUX channel
2749 */
2750static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2751{
2752 i2c_del_adapter(&aux->ddc);
2753}
Linux 6.x block layer and io_uring tree(s)