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Diffstat (limited to 'drivers/gpu/drm/drm_dp_mst_topology.c')
-rw-r--r--drivers/gpu/drm/drm_dp_mst_topology.c2715
1 files changed, 2715 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
new file mode 100644
index 000000000000..ac3c2738db94
--- /dev/null
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -0,0 +1,2715 @@
1/*
2 * Copyright © 2014 Red Hat
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#include <linux/kernel.h>
24#include <linux/delay.h>
25#include <linux/init.h>
26#include <linux/errno.h>
27#include <linux/sched.h>
28#include <linux/seq_file.h>
29#include <linux/i2c.h>
30#include <drm/drm_dp_mst_helper.h>
31#include <drm/drmP.h>
32
33#include <drm/drm_fixed.h>
34
35/**
36 * DOC: dp mst helper
37 *
38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport
39 * protocol. The helpers contain a topology manager and bandwidth manager.
40 * The helpers encapsulate the sending and received of sideband msgs.
41 */
42static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
43 char *buf);
44static int test_calc_pbn_mode(void);
45
46static void drm_dp_put_port(struct drm_dp_mst_port *port);
47
48static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
49 int id,
50 struct drm_dp_payload *payload);
51
52static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
53 struct drm_dp_mst_port *port,
54 int offset, int size, u8 *bytes);
55
56static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
57 struct drm_dp_mst_branch *mstb);
58static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
59 struct drm_dp_mst_branch *mstb,
60 struct drm_dp_mst_port *port);
61static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
62 u8 *guid);
63
64static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux);
65static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux);
66static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
67/* sideband msg handling */
68static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles)
69{
70 u8 bitmask = 0x80;
71 u8 bitshift = 7;
72 u8 array_index = 0;
73 int number_of_bits = num_nibbles * 4;
74 u8 remainder = 0;
75
76 while (number_of_bits != 0) {
77 number_of_bits--;
78 remainder <<= 1;
79 remainder |= (data[array_index] & bitmask) >> bitshift;
80 bitmask >>= 1;
81 bitshift--;
82 if (bitmask == 0) {
83 bitmask = 0x80;
84 bitshift = 7;
85 array_index++;
86 }
87 if ((remainder & 0x10) == 0x10)
88 remainder ^= 0x13;
89 }
90
91 number_of_bits = 4;
92 while (number_of_bits != 0) {
93 number_of_bits--;
94 remainder <<= 1;
95 if ((remainder & 0x10) != 0)
96 remainder ^= 0x13;
97 }
98
99 return remainder;
100}
101
102static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes)
103{
104 u8 bitmask = 0x80;
105 u8 bitshift = 7;
106 u8 array_index = 0;
107 int number_of_bits = number_of_bytes * 8;
108 u16 remainder = 0;
109
110 while (number_of_bits != 0) {
111 number_of_bits--;
112 remainder <<= 1;
113 remainder |= (data[array_index] & bitmask) >> bitshift;
114 bitmask >>= 1;
115 bitshift--;
116 if (bitmask == 0) {
117 bitmask = 0x80;
118 bitshift = 7;
119 array_index++;
120 }
121 if ((remainder & 0x100) == 0x100)
122 remainder ^= 0xd5;
123 }
124
125 number_of_bits = 8;
126 while (number_of_bits != 0) {
127 number_of_bits--;
128 remainder <<= 1;
129 if ((remainder & 0x100) != 0)
130 remainder ^= 0xd5;
131 }
132
133 return remainder & 0xff;
134}
135static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr)
136{
137 u8 size = 3;
138 size += (hdr->lct / 2);
139 return size;
140}
141
142static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
143 u8 *buf, int *len)
144{
145 int idx = 0;
146 int i;
147 u8 crc4;
148 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf);
149 for (i = 0; i < (hdr->lct / 2); i++)
150 buf[idx++] = hdr->rad[i];
151 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) |
152 (hdr->msg_len & 0x3f);
153 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4);
154
155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1);
156 buf[idx - 1] |= (crc4 & 0xf);
157
158 *len = idx;
159}
160
161static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr,
162 u8 *buf, int buflen, u8 *hdrlen)
163{
164 u8 crc4;
165 u8 len;
166 int i;
167 u8 idx;
168 if (buf[0] == 0)
169 return false;
170 len = 3;
171 len += ((buf[0] & 0xf0) >> 4) / 2;
172 if (len > buflen)
173 return false;
174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1);
175
176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) {
177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]);
178 return false;
179 }
180
181 hdr->lct = (buf[0] & 0xf0) >> 4;
182 hdr->lcr = (buf[0] & 0xf);
183 idx = 1;
184 for (i = 0; i < (hdr->lct / 2); i++)
185 hdr->rad[i] = buf[idx++];
186 hdr->broadcast = (buf[idx] >> 7) & 0x1;
187 hdr->path_msg = (buf[idx] >> 6) & 0x1;
188 hdr->msg_len = buf[idx] & 0x3f;
189 idx++;
190 hdr->somt = (buf[idx] >> 7) & 0x1;
191 hdr->eomt = (buf[idx] >> 6) & 0x1;
192 hdr->seqno = (buf[idx] >> 4) & 0x1;
193 idx++;
194 *hdrlen = idx;
195 return true;
196}
197
198static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req,
199 struct drm_dp_sideband_msg_tx *raw)
200{
201 int idx = 0;
202 int i;
203 u8 *buf = raw->msg;
204 buf[idx++] = req->req_type & 0x7f;
205
206 switch (req->req_type) {
207 case DP_ENUM_PATH_RESOURCES:
208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4;
209 idx++;
210 break;
211 case DP_ALLOCATE_PAYLOAD:
212 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 |
213 (req->u.allocate_payload.number_sdp_streams & 0xf);
214 idx++;
215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f);
216 idx++;
217 buf[idx] = (req->u.allocate_payload.pbn >> 8);
218 idx++;
219 buf[idx] = (req->u.allocate_payload.pbn & 0xff);
220 idx++;
221 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) {
222 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) |
223 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf);
224 idx++;
225 }
226 if (req->u.allocate_payload.number_sdp_streams & 1) {
227 i = req->u.allocate_payload.number_sdp_streams - 1;
228 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4;
229 idx++;
230 }
231 break;
232 case DP_QUERY_PAYLOAD:
233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4;
234 idx++;
235 buf[idx] = (req->u.query_payload.vcpi & 0x7f);
236 idx++;
237 break;
238 case DP_REMOTE_DPCD_READ:
239 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4;
240 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf;
241 idx++;
242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8;
243 idx++;
244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff);
245 idx++;
246 buf[idx] = (req->u.dpcd_read.num_bytes);
247 idx++;
248 break;
249
250 case DP_REMOTE_DPCD_WRITE:
251 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4;
252 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf;
253 idx++;
254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8;
255 idx++;
256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff);
257 idx++;
258 buf[idx] = (req->u.dpcd_write.num_bytes);
259 idx++;
260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes);
261 idx += req->u.dpcd_write.num_bytes;
262 break;
263 case DP_REMOTE_I2C_READ:
264 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4;
265 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3);
266 idx++;
267 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) {
268 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f;
269 idx++;
270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes;
271 idx++;
272 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes);
273 idx += req->u.i2c_read.transactions[i].num_bytes;
274
275 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5;
276 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf);
277 idx++;
278 }
279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f;
280 idx++;
281 buf[idx] = (req->u.i2c_read.num_bytes_read);
282 idx++;
283 break;
284
285 case DP_REMOTE_I2C_WRITE:
286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4;
287 idx++;
288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f;
289 idx++;
290 buf[idx] = (req->u.i2c_write.num_bytes);
291 idx++;
292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes);
293 idx += req->u.i2c_write.num_bytes;
294 break;
295 }
296 raw->cur_len = idx;
297}
298
299static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len)
300{
301 u8 crc4;
302 crc4 = drm_dp_msg_data_crc4(msg, len);
303 msg[len] = crc4;
304}
305
306static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep,
307 struct drm_dp_sideband_msg_tx *raw)
308{
309 int idx = 0;
310 u8 *buf = raw->msg;
311
312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f);
313
314 raw->cur_len = idx;
315}
316
317/* this adds a chunk of msg to the builder to get the final msg */
318static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg,
319 u8 *replybuf, u8 replybuflen, bool hdr)
320{
321 int ret;
322 u8 crc4;
323
324 if (hdr) {
325 u8 hdrlen;
326 struct drm_dp_sideband_msg_hdr recv_hdr;
327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen);
328 if (ret == false) {
329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false);
330 return false;
331 }
332
333 /* get length contained in this portion */
334 msg->curchunk_len = recv_hdr.msg_len;
335 msg->curchunk_hdrlen = hdrlen;
336
337 /* we have already gotten an somt - don't bother parsing */
338 if (recv_hdr.somt && msg->have_somt)
339 return false;
340
341 if (recv_hdr.somt) {
342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr));
343 msg->have_somt = true;
344 }
345 if (recv_hdr.eomt)
346 msg->have_eomt = true;
347
348 /* copy the bytes for the remainder of this header chunk */
349 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen));
350 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx);
351 } else {
352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen);
353 msg->curchunk_idx += replybuflen;
354 }
355
356 if (msg->curchunk_idx >= msg->curchunk_len) {
357 /* do CRC */
358 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1);
359 /* copy chunk into bigger msg */
360 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1);
361 msg->curlen += msg->curchunk_len - 1;
362 }
363 return true;
364}
365
366static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw,
367 struct drm_dp_sideband_msg_reply_body *repmsg)
368{
369 int idx = 1;
370 int i;
371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16);
372 idx += 16;
373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf;
374 idx++;
375 if (idx > raw->curlen)
376 goto fail_len;
377 for (i = 0; i < repmsg->u.link_addr.nports; i++) {
378 if (raw->msg[idx] & 0x80)
379 repmsg->u.link_addr.ports[i].input_port = 1;
380
381 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7;
382 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf);
383
384 idx++;
385 if (idx > raw->curlen)
386 goto fail_len;
387 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1;
388 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1;
389 if (repmsg->u.link_addr.ports[i].input_port == 0)
390 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
391 idx++;
392 if (idx > raw->curlen)
393 goto fail_len;
394 if (repmsg->u.link_addr.ports[i].input_port == 0) {
395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]);
396 idx++;
397 if (idx > raw->curlen)
398 goto fail_len;
399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16);
400 idx += 16;
401 if (idx > raw->curlen)
402 goto fail_len;
403 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf;
404 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf);
405 idx++;
406
407 }
408 if (idx > raw->curlen)
409 goto fail_len;
410 }
411
412 return true;
413fail_len:
414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
415 return false;
416}
417
418static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw,
419 struct drm_dp_sideband_msg_reply_body *repmsg)
420{
421 int idx = 1;
422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf;
423 idx++;
424 if (idx > raw->curlen)
425 goto fail_len;
426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
427 if (idx > raw->curlen)
428 goto fail_len;
429
430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
431 return true;
432fail_len:
433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen);
434 return false;
435}
436
437static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw,
438 struct drm_dp_sideband_msg_reply_body *repmsg)
439{
440 int idx = 1;
441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf;
442 idx++;
443 if (idx > raw->curlen)
444 goto fail_len;
445 return true;
446fail_len:
447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen);
448 return false;
449}
450
451static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw,
452 struct drm_dp_sideband_msg_reply_body *repmsg)
453{
454 int idx = 1;
455
456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf);
457 idx++;
458 if (idx > raw->curlen)
459 goto fail_len;
460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
461 idx++;
462 /* TODO check */
463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
464 return true;
465fail_len:
466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen);
467 return false;
468}
469
470static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw,
471 struct drm_dp_sideband_msg_reply_body *repmsg)
472{
473 int idx = 1;
474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
475 idx++;
476 if (idx > raw->curlen)
477 goto fail_len;
478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
479 idx += 2;
480 if (idx > raw->curlen)
481 goto fail_len;
482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
483 idx += 2;
484 if (idx > raw->curlen)
485 goto fail_len;
486 return true;
487fail_len:
488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen);
489 return false;
490}
491
492static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw,
493 struct drm_dp_sideband_msg_reply_body *repmsg)
494{
495 int idx = 1;
496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
497 idx++;
498 if (idx > raw->curlen)
499 goto fail_len;
500 repmsg->u.allocate_payload.vcpi = raw->msg[idx];
501 idx++;
502 if (idx > raw->curlen)
503 goto fail_len;
504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]);
505 idx += 2;
506 if (idx > raw->curlen)
507 goto fail_len;
508 return true;
509fail_len:
510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen);
511 return false;
512}
513
514static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw,
515 struct drm_dp_sideband_msg_reply_body *repmsg)
516{
517 int idx = 1;
518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf;
519 idx++;
520 if (idx > raw->curlen)
521 goto fail_len;
522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
523 idx += 2;
524 if (idx > raw->curlen)
525 goto fail_len;
526 return true;
527fail_len:
528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen);
529 return false;
530}
531
532static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw,
533 struct drm_dp_sideband_msg_reply_body *msg)
534{
535 memset(msg, 0, sizeof(*msg));
536 msg->reply_type = (raw->msg[0] & 0x80) >> 7;
537 msg->req_type = (raw->msg[0] & 0x7f);
538
539 if (msg->reply_type) {
540 memcpy(msg->u.nak.guid, &raw->msg[1], 16);
541 msg->u.nak.reason = raw->msg[17];
542 msg->u.nak.nak_data = raw->msg[18];
543 return false;
544 }
545
546 switch (msg->req_type) {
547 case DP_LINK_ADDRESS:
548 return drm_dp_sideband_parse_link_address(raw, msg);
549 case DP_QUERY_PAYLOAD:
550 return drm_dp_sideband_parse_query_payload_ack(raw, msg);
551 case DP_REMOTE_DPCD_READ:
552 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg);
553 case DP_REMOTE_DPCD_WRITE:
554 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg);
555 case DP_REMOTE_I2C_READ:
556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg);
557 case DP_ENUM_PATH_RESOURCES:
558 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg);
559 case DP_ALLOCATE_PAYLOAD:
560 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg);
561 default:
562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type);
563 return false;
564 }
565}
566
567static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw,
568 struct drm_dp_sideband_msg_req_body *msg)
569{
570 int idx = 1;
571
572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
573 idx++;
574 if (idx > raw->curlen)
575 goto fail_len;
576
577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16);
578 idx += 16;
579 if (idx > raw->curlen)
580 goto fail_len;
581
582 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1;
583 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1;
584 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1;
585 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1;
586 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7);
587 idx++;
588 return true;
589fail_len:
590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen);
591 return false;
592}
593
594static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw,
595 struct drm_dp_sideband_msg_req_body *msg)
596{
597 int idx = 1;
598
599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4;
600 idx++;
601 if (idx > raw->curlen)
602 goto fail_len;
603
604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16);
605 idx += 16;
606 if (idx > raw->curlen)
607 goto fail_len;
608
609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]);
610 idx++;
611 return true;
612fail_len:
613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen);
614 return false;
615}
616
617static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw,
618 struct drm_dp_sideband_msg_req_body *msg)
619{
620 memset(msg, 0, sizeof(*msg));
621 msg->req_type = (raw->msg[0] & 0x7f);
622
623 switch (msg->req_type) {
624 case DP_CONNECTION_STATUS_NOTIFY:
625 return drm_dp_sideband_parse_connection_status_notify(raw, msg);
626 case DP_RESOURCE_STATUS_NOTIFY:
627 return drm_dp_sideband_parse_resource_status_notify(raw, msg);
628 default:
629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type);
630 return false;
631 }
632}
633
634static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes)
635{
636 struct drm_dp_sideband_msg_req_body req;
637
638 req.req_type = DP_REMOTE_DPCD_WRITE;
639 req.u.dpcd_write.port_number = port_num;
640 req.u.dpcd_write.dpcd_address = offset;
641 req.u.dpcd_write.num_bytes = num_bytes;
642 req.u.dpcd_write.bytes = bytes;
643 drm_dp_encode_sideband_req(&req, msg);
644
645 return 0;
646}
647
648static int build_link_address(struct drm_dp_sideband_msg_tx *msg)
649{
650 struct drm_dp_sideband_msg_req_body req;
651
652 req.req_type = DP_LINK_ADDRESS;
653 drm_dp_encode_sideband_req(&req, msg);
654 return 0;
655}
656
657static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num)
658{
659 struct drm_dp_sideband_msg_req_body req;
660
661 req.req_type = DP_ENUM_PATH_RESOURCES;
662 req.u.port_num.port_number = port_num;
663 drm_dp_encode_sideband_req(&req, msg);
664 msg->path_msg = true;
665 return 0;
666}
667
668static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num,
669 u8 vcpi, uint16_t pbn)
670{
671 struct drm_dp_sideband_msg_req_body req;
672 memset(&req, 0, sizeof(req));
673 req.req_type = DP_ALLOCATE_PAYLOAD;
674 req.u.allocate_payload.port_number = port_num;
675 req.u.allocate_payload.vcpi = vcpi;
676 req.u.allocate_payload.pbn = pbn;
677 drm_dp_encode_sideband_req(&req, msg);
678 msg->path_msg = true;
679 return 0;
680}
681
682static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr,
683 struct drm_dp_vcpi *vcpi)
684{
685 int ret;
686
687 mutex_lock(&mgr->payload_lock);
688 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1);
689 if (ret > mgr->max_payloads) {
690 ret = -EINVAL;
691 DRM_DEBUG_KMS("out of payload ids %d\n", ret);
692 goto out_unlock;
693 }
694
695 set_bit(ret, &mgr->payload_mask);
696 vcpi->vcpi = ret;
697 mgr->proposed_vcpis[ret - 1] = vcpi;
698out_unlock:
699 mutex_unlock(&mgr->payload_lock);
700 return ret;
701}
702
703static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr,
704 int id)
705{
706 if (id == 0)
707 return;
708
709 mutex_lock(&mgr->payload_lock);
710 DRM_DEBUG_KMS("putting payload %d\n", id);
711 clear_bit(id, &mgr->payload_mask);
712 mgr->proposed_vcpis[id - 1] = NULL;
713 mutex_unlock(&mgr->payload_lock);
714}
715
716static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr,
717 struct drm_dp_sideband_msg_tx *txmsg)
718{
719 bool ret;
720 mutex_lock(&mgr->qlock);
721 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX ||
722 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT);
723 mutex_unlock(&mgr->qlock);
724 return ret;
725}
726
727static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
728 struct drm_dp_sideband_msg_tx *txmsg)
729{
730 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
731 int ret;
732
733 ret = wait_event_timeout(mgr->tx_waitq,
734 check_txmsg_state(mgr, txmsg),
735 (4 * HZ));
736 mutex_lock(&mstb->mgr->qlock);
737 if (ret > 0) {
738 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) {
739 ret = -EIO;
740 goto out;
741 }
742 } else {
743 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno);
744
745 /* dump some state */
746 ret = -EIO;
747
748 /* remove from q */
749 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
750 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
751 list_del(&txmsg->next);
752 }
753
754 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
755 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
756 mstb->tx_slots[txmsg->seqno] = NULL;
757 }
758 }
759out:
760 mutex_unlock(&mgr->qlock);
761
762 return ret;
763}
764
765static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
766{
767 struct drm_dp_mst_branch *mstb;
768
769 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL);
770 if (!mstb)
771 return NULL;
772
773 mstb->lct = lct;
774 if (lct > 1)
775 memcpy(mstb->rad, rad, lct / 2);
776 INIT_LIST_HEAD(&mstb->ports);
777 kref_init(&mstb->kref);
778 return mstb;
779}
780
781static void drm_dp_destroy_mst_branch_device(struct kref *kref)
782{
783 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
784 struct drm_dp_mst_port *port, *tmp;
785 bool wake_tx = false;
786
787 cancel_work_sync(&mstb->mgr->work);
788
789 /*
790 * destroy all ports - don't need lock
791 * as there are no more references to the mst branch
792 * device at this point.
793 */
794 list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
795 list_del(&port->next);
796 drm_dp_put_port(port);
797 }
798
799 /* drop any tx slots msg */
800 mutex_lock(&mstb->mgr->qlock);
801 if (mstb->tx_slots[0]) {
802 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
803 mstb->tx_slots[0] = NULL;
804 wake_tx = true;
805 }
806 if (mstb->tx_slots[1]) {
807 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
808 mstb->tx_slots[1] = NULL;
809 wake_tx = true;
810 }
811 mutex_unlock(&mstb->mgr->qlock);
812
813 if (wake_tx)
814 wake_up(&mstb->mgr->tx_waitq);
815 kfree(mstb);
816}
817
818static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
819{
820 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device);
821}
822
823
824static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt)
825{
826 switch (old_pdt) {
827 case DP_PEER_DEVICE_DP_LEGACY_CONV:
828 case DP_PEER_DEVICE_SST_SINK:
829 /* remove i2c over sideband */
830 drm_dp_mst_unregister_i2c_bus(&port->aux);
831 break;
832 case DP_PEER_DEVICE_MST_BRANCHING:
833 drm_dp_put_mst_branch_device(port->mstb);
834 port->mstb = NULL;
835 break;
836 }
837}
838
839static void drm_dp_destroy_port(struct kref *kref)
840{
841 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
842 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
843 if (!port->input) {
844 port->vcpi.num_slots = 0;
845 if (port->connector)
846 (*port->mgr->cbs->destroy_connector)(mgr, port->connector);
847 drm_dp_port_teardown_pdt(port, port->pdt);
848
849 if (!port->input && port->vcpi.vcpi > 0)
850 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
851 }
852 kfree(port);
853
854 (*mgr->cbs->hotplug)(mgr);
855}
856
857static void drm_dp_put_port(struct drm_dp_mst_port *port)
858{
859 kref_put(&port->kref, drm_dp_destroy_port);
860}
861
862static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find)
863{
864 struct drm_dp_mst_port *port;
865 struct drm_dp_mst_branch *rmstb;
866 if (to_find == mstb) {
867 kref_get(&mstb->kref);
868 return mstb;
869 }
870 list_for_each_entry(port, &mstb->ports, next) {
871 if (port->mstb) {
872 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find);
873 if (rmstb)
874 return rmstb;
875 }
876 }
877 return NULL;
878}
879
880static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb)
881{
882 struct drm_dp_mst_branch *rmstb = NULL;
883 mutex_lock(&mgr->lock);
884 if (mgr->mst_primary)
885 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb);
886 mutex_unlock(&mgr->lock);
887 return rmstb;
888}
889
890static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find)
891{
892 struct drm_dp_mst_port *port, *mport;
893
894 list_for_each_entry(port, &mstb->ports, next) {
895 if (port == to_find) {
896 kref_get(&port->kref);
897 return port;
898 }
899 if (port->mstb) {
900 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find);
901 if (mport)
902 return mport;
903 }
904 }
905 return NULL;
906}
907
908static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
909{
910 struct drm_dp_mst_port *rport = NULL;
911 mutex_lock(&mgr->lock);
912 if (mgr->mst_primary)
913 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
914 mutex_unlock(&mgr->lock);
915 return rport;
916}
917
918static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num)
919{
920 struct drm_dp_mst_port *port;
921
922 list_for_each_entry(port, &mstb->ports, next) {
923 if (port->port_num == port_num) {
924 kref_get(&port->kref);
925 return port;
926 }
927 }
928
929 return NULL;
930}
931
932/*
933 * calculate a new RAD for this MST branch device
934 * if parent has an LCT of 2 then it has 1 nibble of RAD,
935 * if parent has an LCT of 3 then it has 2 nibbles of RAD,
936 */
937static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port,
938 u8 *rad)
939{
940 int lct = port->parent->lct;
941 int shift = 4;
942 int idx = lct / 2;
943 if (lct > 1) {
944 memcpy(rad, port->parent->rad, idx);
945 shift = (lct % 2) ? 4 : 0;
946 } else
947 rad[0] = 0;
948
949 rad[idx] |= port->port_num << shift;
950 return lct + 1;
951}
952
953/*
954 * return sends link address for new mstb
955 */
956static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port)
957{
958 int ret;
959 u8 rad[6], lct;
960 bool send_link = false;
961 switch (port->pdt) {
962 case DP_PEER_DEVICE_DP_LEGACY_CONV:
963 case DP_PEER_DEVICE_SST_SINK:
964 /* add i2c over sideband */
965 ret = drm_dp_mst_register_i2c_bus(&port->aux);
966 break;
967 case DP_PEER_DEVICE_MST_BRANCHING:
968 lct = drm_dp_calculate_rad(port, rad);
969
970 port->mstb = drm_dp_add_mst_branch_device(lct, rad);
971 port->mstb->mgr = port->mgr;
972 port->mstb->port_parent = port;
973
974 send_link = true;
975 break;
976 }
977 return send_link;
978}
979
980static void drm_dp_check_port_guid(struct drm_dp_mst_branch *mstb,
981 struct drm_dp_mst_port *port)
982{
983 int ret;
984 if (port->dpcd_rev >= 0x12) {
985 port->guid_valid = drm_dp_validate_guid(mstb->mgr, port->guid);
986 if (!port->guid_valid) {
987 ret = drm_dp_send_dpcd_write(mstb->mgr,
988 port,
989 DP_GUID,
990 16, port->guid);
991 port->guid_valid = true;
992 }
993 }
994}
995
996static void build_mst_prop_path(struct drm_dp_mst_port *port,
997 struct drm_dp_mst_branch *mstb,
998 char *proppath)
999{
1000 int i;
1001 char temp[8];
1002 snprintf(proppath, 255, "mst:%d", mstb->mgr->conn_base_id);
1003 for (i = 0; i < (mstb->lct - 1); i++) {
1004 int shift = (i % 2) ? 0 : 4;
1005 int port_num = mstb->rad[i / 2] >> shift;
1006 snprintf(temp, 8, "-%d", port_num);
1007 strncat(proppath, temp, 255);
1008 }
1009 snprintf(temp, 8, "-%d", port->port_num);
1010 strncat(proppath, temp, 255);
1011}
1012
1013static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
1014 struct device *dev,
1015 struct drm_dp_link_addr_reply_port *port_msg)
1016{
1017 struct drm_dp_mst_port *port;
1018 bool ret;
1019 bool created = false;
1020 int old_pdt = 0;
1021 int old_ddps = 0;
1022 port = drm_dp_get_port(mstb, port_msg->port_number);
1023 if (!port) {
1024 port = kzalloc(sizeof(*port), GFP_KERNEL);
1025 if (!port)
1026 return;
1027 kref_init(&port->kref);
1028 port->parent = mstb;
1029 port->port_num = port_msg->port_number;
1030 port->mgr = mstb->mgr;
1031 port->aux.name = "DPMST";
1032 port->aux.dev = dev;
1033 created = true;
1034 } else {
1035 old_pdt = port->pdt;
1036 old_ddps = port->ddps;
1037 }
1038
1039 port->pdt = port_msg->peer_device_type;
1040 port->input = port_msg->input_port;
1041 port->mcs = port_msg->mcs;
1042 port->ddps = port_msg->ddps;
1043 port->ldps = port_msg->legacy_device_plug_status;
1044 port->dpcd_rev = port_msg->dpcd_revision;
1045 port->num_sdp_streams = port_msg->num_sdp_streams;
1046 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks;
1047 memcpy(port->guid, port_msg->peer_guid, 16);
1048
1049 /* manage mstb port lists with mgr lock - take a reference
1050 for this list */
1051 if (created) {
1052 mutex_lock(&mstb->mgr->lock);
1053 kref_get(&port->kref);
1054 list_add(&port->next, &mstb->ports);
1055 mutex_unlock(&mstb->mgr->lock);
1056 }
1057
1058 if (old_ddps != port->ddps) {
1059 if (port->ddps) {
1060 drm_dp_check_port_guid(mstb, port);
1061 if (!port->input)
1062 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port);
1063 } else {
1064 port->guid_valid = false;
1065 port->available_pbn = 0;
1066 }
1067 }
1068
1069 if (old_pdt != port->pdt && !port->input) {
1070 drm_dp_port_teardown_pdt(port, old_pdt);
1071
1072 ret = drm_dp_port_setup_pdt(port);
1073 if (ret == true) {
1074 drm_dp_send_link_address(mstb->mgr, port->mstb);
1075 port->mstb->link_address_sent = true;
1076 }
1077 }
1078
1079 if (created && !port->input) {
1080 char proppath[255];
1081 build_mst_prop_path(port, mstb, proppath);
1082 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath);
1083 }
1084
1085 /* put reference to this port */
1086 drm_dp_put_port(port);
1087}
1088
1089static void drm_dp_update_port(struct drm_dp_mst_branch *mstb,
1090 struct drm_dp_connection_status_notify *conn_stat)
1091{
1092 struct drm_dp_mst_port *port;
1093 int old_pdt;
1094 int old_ddps;
1095 bool dowork = false;
1096 port = drm_dp_get_port(mstb, conn_stat->port_number);
1097 if (!port)
1098 return;
1099
1100 old_ddps = port->ddps;
1101 old_pdt = port->pdt;
1102 port->pdt = conn_stat->peer_device_type;
1103 port->mcs = conn_stat->message_capability_status;
1104 port->ldps = conn_stat->legacy_device_plug_status;
1105 port->ddps = conn_stat->displayport_device_plug_status;
1106
1107 if (old_ddps != port->ddps) {
1108 if (port->ddps) {
1109 drm_dp_check_port_guid(mstb, port);
1110 dowork = true;
1111 } else {
1112 port->guid_valid = false;
1113 port->available_pbn = 0;
1114 }
1115 }
1116 if (old_pdt != port->pdt && !port->input) {
1117 drm_dp_port_teardown_pdt(port, old_pdt);
1118
1119 if (drm_dp_port_setup_pdt(port))
1120 dowork = true;
1121 }
1122
1123 drm_dp_put_port(port);
1124 if (dowork)
1125 queue_work(system_long_wq, &mstb->mgr->work);
1126
1127}
1128
1129static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
1130 u8 lct, u8 *rad)
1131{
1132 struct drm_dp_mst_branch *mstb;
1133 struct drm_dp_mst_port *port;
1134 int i;
1135 /* find the port by iterating down */
1136 mstb = mgr->mst_primary;
1137
1138 for (i = 0; i < lct - 1; i++) {
1139 int shift = (i % 2) ? 0 : 4;
1140 int port_num = rad[i / 2] >> shift;
1141
1142 list_for_each_entry(port, &mstb->ports, next) {
1143 if (port->port_num == port_num) {
1144 if (!port->mstb) {
1145 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]);
1146 return NULL;
1147 }
1148
1149 mstb = port->mstb;
1150 break;
1151 }
1152 }
1153 }
1154 kref_get(&mstb->kref);
1155 return mstb;
1156}
1157
1158static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1159 struct drm_dp_mst_branch *mstb)
1160{
1161 struct drm_dp_mst_port *port;
1162
1163 if (!mstb->link_address_sent) {
1164 drm_dp_send_link_address(mgr, mstb);
1165 mstb->link_address_sent = true;
1166 }
1167 list_for_each_entry(port, &mstb->ports, next) {
1168 if (port->input)
1169 continue;
1170
1171 if (!port->ddps)
1172 continue;
1173
1174 if (!port->available_pbn)
1175 drm_dp_send_enum_path_resources(mgr, mstb, port);
1176
1177 if (port->mstb)
1178 drm_dp_check_and_send_link_address(mgr, port->mstb);
1179 }
1180}
1181
1182static void drm_dp_mst_link_probe_work(struct work_struct *work)
1183{
1184 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
1185
1186 drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
1187
1188}
1189
1190static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,
1191 u8 *guid)
1192{
1193 static u8 zero_guid[16];
1194
1195 if (!memcmp(guid, zero_guid, 16)) {
1196 u64 salt = get_jiffies_64();
1197 memcpy(&guid[0], &salt, sizeof(u64));
1198 memcpy(&guid[8], &salt, sizeof(u64));
1199 return false;
1200 }
1201 return true;
1202}
1203
1204#if 0
1205static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
1206{
1207 struct drm_dp_sideband_msg_req_body req;
1208
1209 req.req_type = DP_REMOTE_DPCD_READ;
1210 req.u.dpcd_read.port_number = port_num;
1211 req.u.dpcd_read.dpcd_address = offset;
1212 req.u.dpcd_read.num_bytes = num_bytes;
1213 drm_dp_encode_sideband_req(&req, msg);
1214
1215 return 0;
1216}
1217#endif
1218
1219static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
1220 bool up, u8 *msg, int len)
1221{
1222 int ret;
1223 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE;
1224 int tosend, total, offset;
1225 int retries = 0;
1226
1227retry:
1228 total = len;
1229 offset = 0;
1230 do {
1231 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total);
1232
1233 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset,
1234 &msg[offset],
1235 tosend);
1236 if (ret != tosend) {
1237 if (ret == -EIO && retries < 5) {
1238 retries++;
1239 goto retry;
1240 }
1241 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret);
1242 WARN(1, "fail\n");
1243
1244 return -EIO;
1245 }
1246 offset += tosend;
1247 total -= tosend;
1248 } while (total > 0);
1249 return 0;
1250}
1251
1252static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
1253 struct drm_dp_sideband_msg_tx *txmsg)
1254{
1255 struct drm_dp_mst_branch *mstb = txmsg->dst;
1256
1257 /* both msg slots are full */
1258 if (txmsg->seqno == -1) {
1259 if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
1260 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
1261 return -EAGAIN;
1262 }
1263 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
1264 txmsg->seqno = mstb->last_seqno;
1265 mstb->last_seqno ^= 1;
1266 } else if (mstb->tx_slots[0] == NULL)
1267 txmsg->seqno = 0;
1268 else
1269 txmsg->seqno = 1;
1270 mstb->tx_slots[txmsg->seqno] = txmsg;
1271 }
1272 hdr->broadcast = 0;
1273 hdr->path_msg = txmsg->path_msg;
1274 hdr->lct = mstb->lct;
1275 hdr->lcr = mstb->lct - 1;
1276 if (mstb->lct > 1)
1277 memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
1278 hdr->seqno = txmsg->seqno;
1279 return 0;
1280}
1281/*
1282 * process a single block of the next message in the sideband queue
1283 */
1284static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
1285 struct drm_dp_sideband_msg_tx *txmsg,
1286 bool up)
1287{
1288 u8 chunk[48];
1289 struct drm_dp_sideband_msg_hdr hdr;
1290 int len, space, idx, tosend;
1291 int ret;
1292
1293 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
1294
1295 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
1296 txmsg->seqno = -1;
1297 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
1298 }
1299
1300 /* make hdr from dst mst - for replies use seqno
1301 otherwise assign one */
1302 ret = set_hdr_from_dst_qlock(&hdr, txmsg);
1303 if (ret < 0)
1304 return ret;
1305
1306 /* amount left to send in this message */
1307 len = txmsg->cur_len - txmsg->cur_offset;
1308
1309 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */
1310 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr);
1311
1312 tosend = min(len, space);
1313 if (len == txmsg->cur_len)
1314 hdr.somt = 1;
1315 if (space >= len)
1316 hdr.eomt = 1;
1317
1318
1319 hdr.msg_len = tosend + 1;
1320 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx);
1321 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend);
1322 /* add crc at end */
1323 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend);
1324 idx += tosend + 1;
1325
1326 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
1327 if (ret) {
1328 DRM_DEBUG_KMS("sideband msg failed to send\n");
1329 return ret;
1330 }
1331
1332 txmsg->cur_offset += tosend;
1333 if (txmsg->cur_offset == txmsg->cur_len) {
1334 txmsg->state = DRM_DP_SIDEBAND_TX_SENT;
1335 return 1;
1336 }
1337 return 0;
1338}
1339
1340/* must be called holding qlock */
1341static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1342{
1343 struct drm_dp_sideband_msg_tx *txmsg;
1344 int ret;
1345
1346 /* construct a chunk from the first msg in the tx_msg queue */
1347 if (list_empty(&mgr->tx_msg_downq)) {
1348 mgr->tx_down_in_progress = false;
1349 return;
1350 }
1351 mgr->tx_down_in_progress = true;
1352
1353 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
1354 ret = process_single_tx_qlock(mgr, txmsg, false);
1355 if (ret == 1) {
1356 /* txmsg is sent it should be in the slots now */
1357 list_del(&txmsg->next);
1358 } else if (ret) {
1359 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1360 list_del(&txmsg->next);
1361 if (txmsg->seqno != -1)
1362 txmsg->dst->tx_slots[txmsg->seqno] = NULL;
1363 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
1364 wake_up(&mgr->tx_waitq);
1365 }
1366 if (list_empty(&mgr->tx_msg_downq)) {
1367 mgr->tx_down_in_progress = false;
1368 return;
1369 }
1370}
1371
1372/* called holding qlock */
1373static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
1374{
1375 struct drm_dp_sideband_msg_tx *txmsg;
1376 int ret;
1377
1378 /* construct a chunk from the first msg in the tx_msg queue */
1379 if (list_empty(&mgr->tx_msg_upq)) {
1380 mgr->tx_up_in_progress = false;
1381 return;
1382 }
1383
1384 txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
1385 ret = process_single_tx_qlock(mgr, txmsg, true);
1386 if (ret == 1) {
1387 /* up txmsgs aren't put in slots - so free after we send it */
1388 list_del(&txmsg->next);
1389 kfree(txmsg);
1390 } else if (ret)
1391 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
1392 mgr->tx_up_in_progress = true;
1393}
1394
1395static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
1396 struct drm_dp_sideband_msg_tx *txmsg)
1397{
1398 mutex_lock(&mgr->qlock);
1399 list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
1400 if (!mgr->tx_down_in_progress)
1401 process_single_down_tx_qlock(mgr);
1402 mutex_unlock(&mgr->qlock);
1403}
1404
1405static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,
1406 struct drm_dp_mst_branch *mstb)
1407{
1408 int len;
1409 struct drm_dp_sideband_msg_tx *txmsg;
1410 int ret;
1411
1412 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1413 if (!txmsg)
1414 return -ENOMEM;
1415
1416 txmsg->dst = mstb;
1417 len = build_link_address(txmsg);
1418
1419 drm_dp_queue_down_tx(mgr, txmsg);
1420
1421 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1422 if (ret > 0) {
1423 int i;
1424
1425 if (txmsg->reply.reply_type == 1)
1426 DRM_DEBUG_KMS("link address nak received\n");
1427 else {
1428 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports);
1429 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1430 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,
1431 txmsg->reply.u.link_addr.ports[i].input_port,
1432 txmsg->reply.u.link_addr.ports[i].peer_device_type,
1433 txmsg->reply.u.link_addr.ports[i].port_number,
1434 txmsg->reply.u.link_addr.ports[i].dpcd_revision,
1435 txmsg->reply.u.link_addr.ports[i].mcs,
1436 txmsg->reply.u.link_addr.ports[i].ddps,
1437 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status,
1438 txmsg->reply.u.link_addr.ports[i].num_sdp_streams,
1439 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks);
1440 }
1441 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) {
1442 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]);
1443 }
1444 (*mgr->cbs->hotplug)(mgr);
1445 }
1446 } else
1447 DRM_DEBUG_KMS("link address failed %d\n", ret);
1448
1449 kfree(txmsg);
1450 return 0;
1451}
1452
1453static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
1454 struct drm_dp_mst_branch *mstb,
1455 struct drm_dp_mst_port *port)
1456{
1457 int len;
1458 struct drm_dp_sideband_msg_tx *txmsg;
1459 int ret;
1460
1461 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1462 if (!txmsg)
1463 return -ENOMEM;
1464
1465 txmsg->dst = mstb;
1466 len = build_enum_path_resources(txmsg, port->port_num);
1467
1468 drm_dp_queue_down_tx(mgr, txmsg);
1469
1470 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1471 if (ret > 0) {
1472 if (txmsg->reply.reply_type == 1)
1473 DRM_DEBUG_KMS("enum path resources nak received\n");
1474 else {
1475 if (port->port_num != txmsg->reply.u.path_resources.port_number)
1476 DRM_ERROR("got incorrect port in response\n");
1477 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,
1478 txmsg->reply.u.path_resources.avail_payload_bw_number);
1479 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number;
1480 }
1481 }
1482
1483 kfree(txmsg);
1484 return 0;
1485}
1486
1487static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
1488 struct drm_dp_mst_port *port,
1489 int id,
1490 int pbn)
1491{
1492 struct drm_dp_sideband_msg_tx *txmsg;
1493 struct drm_dp_mst_branch *mstb;
1494 int len, ret;
1495
1496 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1497 if (!mstb)
1498 return -EINVAL;
1499
1500 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1501 if (!txmsg) {
1502 ret = -ENOMEM;
1503 goto fail_put;
1504 }
1505
1506 txmsg->dst = mstb;
1507 len = build_allocate_payload(txmsg, port->port_num,
1508 id,
1509 pbn);
1510
1511 drm_dp_queue_down_tx(mgr, txmsg);
1512
1513 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1514 if (ret > 0) {
1515 if (txmsg->reply.reply_type == 1) {
1516 ret = -EINVAL;
1517 } else
1518 ret = 0;
1519 }
1520 kfree(txmsg);
1521fail_put:
1522 drm_dp_put_mst_branch_device(mstb);
1523 return ret;
1524}
1525
1526static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1527 int id,
1528 struct drm_dp_payload *payload)
1529{
1530 int ret;
1531
1532 ret = drm_dp_dpcd_write_payload(mgr, id, payload);
1533 if (ret < 0) {
1534 payload->payload_state = 0;
1535 return ret;
1536 }
1537 payload->payload_state = DP_PAYLOAD_LOCAL;
1538 return 0;
1539}
1540
1541static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1542 struct drm_dp_mst_port *port,
1543 int id,
1544 struct drm_dp_payload *payload)
1545{
1546 int ret;
1547 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn);
1548 if (ret < 0)
1549 return ret;
1550 payload->payload_state = DP_PAYLOAD_REMOTE;
1551 return ret;
1552}
1553
1554static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr,
1555 struct drm_dp_mst_port *port,
1556 int id,
1557 struct drm_dp_payload *payload)
1558{
1559 DRM_DEBUG_KMS("\n");
1560 /* its okay for these to fail */
1561 if (port) {
1562 drm_dp_payload_send_msg(mgr, port, id, 0);
1563 }
1564
1565 drm_dp_dpcd_write_payload(mgr, id, payload);
1566 payload->payload_state = 0;
1567 return 0;
1568}
1569
1570static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr,
1571 int id,
1572 struct drm_dp_payload *payload)
1573{
1574 payload->payload_state = 0;
1575 return 0;
1576}
1577
1578/**
1579 * drm_dp_update_payload_part1() - Execute payload update part 1
1580 * @mgr: manager to use.
1581 *
1582 * This iterates over all proposed virtual channels, and tries to
1583 * allocate space in the link for them. For 0->slots transitions,
1584 * this step just writes the VCPI to the MST device. For slots->0
1585 * transitions, this writes the updated VCPIs and removes the
1586 * remote VC payloads.
1587 *
1588 * after calling this the driver should generate ACT and payload
1589 * packets.
1590 */
1591int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
1592{
1593 int i;
1594 int cur_slots = 1;
1595 struct drm_dp_payload req_payload;
1596 struct drm_dp_mst_port *port;
1597
1598 mutex_lock(&mgr->payload_lock);
1599 for (i = 0; i < mgr->max_payloads; i++) {
1600 /* solve the current payloads - compare to the hw ones
1601 - update the hw view */
1602 req_payload.start_slot = cur_slots;
1603 if (mgr->proposed_vcpis[i]) {
1604 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1605 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots;
1606 } else {
1607 port = NULL;
1608 req_payload.num_slots = 0;
1609 }
1610 /* work out what is required to happen with this payload */
1611 if (mgr->payloads[i].start_slot != req_payload.start_slot ||
1612 mgr->payloads[i].num_slots != req_payload.num_slots) {
1613
1614 /* need to push an update for this payload */
1615 if (req_payload.num_slots) {
1616 drm_dp_create_payload_step1(mgr, i + 1, &req_payload);
1617 mgr->payloads[i].num_slots = req_payload.num_slots;
1618 } else if (mgr->payloads[i].num_slots) {
1619 mgr->payloads[i].num_slots = 0;
1620 drm_dp_destroy_payload_step1(mgr, port, i + 1, &mgr->payloads[i]);
1621 req_payload.payload_state = mgr->payloads[i].payload_state;
1622 } else
1623 req_payload.payload_state = 0;
1624
1625 mgr->payloads[i].start_slot = req_payload.start_slot;
1626 mgr->payloads[i].payload_state = req_payload.payload_state;
1627 }
1628 cur_slots += req_payload.num_slots;
1629 }
1630 mutex_unlock(&mgr->payload_lock);
1631
1632 return 0;
1633}
1634EXPORT_SYMBOL(drm_dp_update_payload_part1);
1635
1636/**
1637 * drm_dp_update_payload_part2() - Execute payload update part 2
1638 * @mgr: manager to use.
1639 *
1640 * This iterates over all proposed virtual channels, and tries to
1641 * allocate space in the link for them. For 0->slots transitions,
1642 * this step writes the remote VC payload commands. For slots->0
1643 * this just resets some internal state.
1644 */
1645int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
1646{
1647 struct drm_dp_mst_port *port;
1648 int i;
1649 int ret = 0;
1650 mutex_lock(&mgr->payload_lock);
1651 for (i = 0; i < mgr->max_payloads; i++) {
1652
1653 if (!mgr->proposed_vcpis[i])
1654 continue;
1655
1656 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
1657
1658 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state);
1659 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
1660 ret = drm_dp_create_payload_step2(mgr, port, i + 1, &mgr->payloads[i]);
1661 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) {
1662 ret = drm_dp_destroy_payload_step2(mgr, i + 1, &mgr->payloads[i]);
1663 }
1664 if (ret) {
1665 mutex_unlock(&mgr->payload_lock);
1666 return ret;
1667 }
1668 }
1669 mutex_unlock(&mgr->payload_lock);
1670 return 0;
1671}
1672EXPORT_SYMBOL(drm_dp_update_payload_part2);
1673
1674#if 0 /* unused as of yet */
1675static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
1676 struct drm_dp_mst_port *port,
1677 int offset, int size)
1678{
1679 int len;
1680 struct drm_dp_sideband_msg_tx *txmsg;
1681
1682 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1683 if (!txmsg)
1684 return -ENOMEM;
1685
1686 len = build_dpcd_read(txmsg, port->port_num, 0, 8);
1687 txmsg->dst = port->parent;
1688
1689 drm_dp_queue_down_tx(mgr, txmsg);
1690
1691 return 0;
1692}
1693#endif
1694
1695static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
1696 struct drm_dp_mst_port *port,
1697 int offset, int size, u8 *bytes)
1698{
1699 int len;
1700 int ret;
1701 struct drm_dp_sideband_msg_tx *txmsg;
1702 struct drm_dp_mst_branch *mstb;
1703
1704 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
1705 if (!mstb)
1706 return -EINVAL;
1707
1708 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1709 if (!txmsg) {
1710 ret = -ENOMEM;
1711 goto fail_put;
1712 }
1713
1714 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes);
1715 txmsg->dst = mstb;
1716
1717 drm_dp_queue_down_tx(mgr, txmsg);
1718
1719 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
1720 if (ret > 0) {
1721 if (txmsg->reply.reply_type == 1) {
1722 ret = -EINVAL;
1723 } else
1724 ret = 0;
1725 }
1726 kfree(txmsg);
1727fail_put:
1728 drm_dp_put_mst_branch_device(mstb);
1729 return ret;
1730}
1731
1732static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type)
1733{
1734 struct drm_dp_sideband_msg_reply_body reply;
1735
1736 reply.reply_type = 1;
1737 reply.req_type = req_type;
1738 drm_dp_encode_sideband_reply(&reply, msg);
1739 return 0;
1740}
1741
1742static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
1743 struct drm_dp_mst_branch *mstb,
1744 int req_type, int seqno, bool broadcast)
1745{
1746 struct drm_dp_sideband_msg_tx *txmsg;
1747
1748 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
1749 if (!txmsg)
1750 return -ENOMEM;
1751
1752 txmsg->dst = mstb;
1753 txmsg->seqno = seqno;
1754 drm_dp_encode_up_ack_reply(txmsg, req_type);
1755
1756 mutex_lock(&mgr->qlock);
1757 list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
1758 if (!mgr->tx_up_in_progress) {
1759 process_single_up_tx_qlock(mgr);
1760 }
1761 mutex_unlock(&mgr->qlock);
1762 return 0;
1763}
1764
1765static int drm_dp_get_vc_payload_bw(int dp_link_bw, int dp_link_count)
1766{
1767 switch (dp_link_bw) {
1768 case DP_LINK_BW_1_62:
1769 return 3 * dp_link_count;
1770 case DP_LINK_BW_2_7:
1771 return 5 * dp_link_count;
1772 case DP_LINK_BW_5_4:
1773 return 10 * dp_link_count;
1774 }
1775 return 0;
1776}
1777
1778/**
1779 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager
1780 * @mgr: manager to set state for
1781 * @mst_state: true to enable MST on this connector - false to disable.
1782 *
1783 * This is called by the driver when it detects an MST capable device plugged
1784 * into a DP MST capable port, or when a DP MST capable device is unplugged.
1785 */
1786int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state)
1787{
1788 int ret = 0;
1789 struct drm_dp_mst_branch *mstb = NULL;
1790
1791 mutex_lock(&mgr->lock);
1792 if (mst_state == mgr->mst_state)
1793 goto out_unlock;
1794
1795 mgr->mst_state = mst_state;
1796 /* set the device into MST mode */
1797 if (mst_state) {
1798 WARN_ON(mgr->mst_primary);
1799
1800 /* get dpcd info */
1801 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1802 if (ret != DP_RECEIVER_CAP_SIZE) {
1803 DRM_DEBUG_KMS("failed to read DPCD\n");
1804 goto out_unlock;
1805 }
1806
1807 mgr->pbn_div = drm_dp_get_vc_payload_bw(mgr->dpcd[1], mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK);
1808 mgr->total_pbn = 2560;
1809 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div);
1810 mgr->avail_slots = mgr->total_slots;
1811
1812 /* add initial branch device at LCT 1 */
1813 mstb = drm_dp_add_mst_branch_device(1, NULL);
1814 if (mstb == NULL) {
1815 ret = -ENOMEM;
1816 goto out_unlock;
1817 }
1818 mstb->mgr = mgr;
1819
1820 /* give this the main reference */
1821 mgr->mst_primary = mstb;
1822 kref_get(&mgr->mst_primary->kref);
1823
1824 {
1825 struct drm_dp_payload reset_pay;
1826 reset_pay.start_slot = 0;
1827 reset_pay.num_slots = 0x3f;
1828 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay);
1829 }
1830
1831 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1832 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1833 if (ret < 0) {
1834 goto out_unlock;
1835 }
1836
1837
1838 /* sort out guid */
1839 ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, mgr->guid, 16);
1840 if (ret != 16) {
1841 DRM_DEBUG_KMS("failed to read DP GUID %d\n", ret);
1842 goto out_unlock;
1843 }
1844
1845 mgr->guid_valid = drm_dp_validate_guid(mgr, mgr->guid);
1846 if (!mgr->guid_valid) {
1847 ret = drm_dp_dpcd_write(mgr->aux, DP_GUID, mgr->guid, 16);
1848 mgr->guid_valid = true;
1849 }
1850
1851 queue_work(system_long_wq, &mgr->work);
1852
1853 ret = 0;
1854 } else {
1855 /* disable MST on the device */
1856 mstb = mgr->mst_primary;
1857 mgr->mst_primary = NULL;
1858 /* this can fail if the device is gone */
1859 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0);
1860 ret = 0;
1861 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload));
1862 mgr->payload_mask = 0;
1863 set_bit(0, &mgr->payload_mask);
1864 }
1865
1866out_unlock:
1867 mutex_unlock(&mgr->lock);
1868 if (mstb)
1869 drm_dp_put_mst_branch_device(mstb);
1870 return ret;
1871
1872}
1873EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst);
1874
1875/**
1876 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager
1877 * @mgr: manager to suspend
1878 *
1879 * This function tells the MST device that we can't handle UP messages
1880 * anymore. This should stop it from sending any since we are suspended.
1881 */
1882void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
1883{
1884 mutex_lock(&mgr->lock);
1885 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1886 DP_MST_EN | DP_UPSTREAM_IS_SRC);
1887 mutex_unlock(&mgr->lock);
1888}
1889EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
1890
1891/**
1892 * drm_dp_mst_topology_mgr_resume() - resume the MST manager
1893 * @mgr: manager to resume
1894 *
1895 * This will fetch DPCD and see if the device is still there,
1896 * if it is, it will rewrite the MSTM control bits, and return.
1897 *
1898 * if the device fails this returns -1, and the driver should do
1899 * a full MST reprobe, in case we were undocked.
1900 */
1901int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
1902{
1903 int ret = 0;
1904
1905 mutex_lock(&mgr->lock);
1906
1907 if (mgr->mst_primary) {
1908 int sret;
1909 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE);
1910 if (sret != DP_RECEIVER_CAP_SIZE) {
1911 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n");
1912 ret = -1;
1913 goto out_unlock;
1914 }
1915
1916 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL,
1917 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC);
1918 if (ret < 0) {
1919 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n");
1920 ret = -1;
1921 goto out_unlock;
1922 }
1923 ret = 0;
1924 } else
1925 ret = -1;
1926
1927out_unlock:
1928 mutex_unlock(&mgr->lock);
1929 return ret;
1930}
1931EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
1932
1933static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up)
1934{
1935 int len;
1936 u8 replyblock[32];
1937 int replylen, origlen, curreply;
1938 int ret;
1939 struct drm_dp_sideband_msg_rx *msg;
1940 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE;
1941 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv;
1942
1943 len = min(mgr->max_dpcd_transaction_bytes, 16);
1944 ret = drm_dp_dpcd_read(mgr->aux, basereg,
1945 replyblock, len);
1946 if (ret != len) {
1947 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret);
1948 return;
1949 }
1950 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true);
1951 if (!ret) {
1952 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]);
1953 return;
1954 }
1955 replylen = msg->curchunk_len + msg->curchunk_hdrlen;
1956
1957 origlen = replylen;
1958 replylen -= len;
1959 curreply = len;
1960 while (replylen > 0) {
1961 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16);
1962 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply,
1963 replyblock, len);
1964 if (ret != len) {
1965 DRM_DEBUG_KMS("failed to read a chunk\n");
1966 }
1967 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false);
1968 if (ret == false)
1969 DRM_DEBUG_KMS("failed to build sideband msg\n");
1970 curreply += len;
1971 replylen -= len;
1972 }
1973}
1974
1975static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
1976{
1977 int ret = 0;
1978
1979 drm_dp_get_one_sb_msg(mgr, false);
1980
1981 if (mgr->down_rep_recv.have_eomt) {
1982 struct drm_dp_sideband_msg_tx *txmsg;
1983 struct drm_dp_mst_branch *mstb;
1984 int slot = -1;
1985 mstb = drm_dp_get_mst_branch_device(mgr,
1986 mgr->down_rep_recv.initial_hdr.lct,
1987 mgr->down_rep_recv.initial_hdr.rad);
1988
1989 if (!mstb) {
1990 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct);
1991 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
1992 return 0;
1993 }
1994
1995 /* find the message */
1996 slot = mgr->down_rep_recv.initial_hdr.seqno;
1997 mutex_lock(&mgr->qlock);
1998 txmsg = mstb->tx_slots[slot];
1999 /* remove from slots */
2000 mutex_unlock(&mgr->qlock);
2001
2002 if (!txmsg) {
2003 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
2004 mstb,
2005 mgr->down_rep_recv.initial_hdr.seqno,
2006 mgr->down_rep_recv.initial_hdr.lct,
2007 mgr->down_rep_recv.initial_hdr.rad[0],
2008 mgr->down_rep_recv.msg[0]);
2009 drm_dp_put_mst_branch_device(mstb);
2010 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2011 return 0;
2012 }
2013
2014 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply);
2015 if (txmsg->reply.reply_type == 1) {
2016 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);
2017 }
2018
2019 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2020 drm_dp_put_mst_branch_device(mstb);
2021
2022 mutex_lock(&mgr->qlock);
2023 txmsg->state = DRM_DP_SIDEBAND_TX_RX;
2024 mstb->tx_slots[slot] = NULL;
2025 mutex_unlock(&mgr->qlock);
2026
2027 wake_up(&mgr->tx_waitq);
2028 }
2029 return ret;
2030}
2031
2032static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
2033{
2034 int ret = 0;
2035 drm_dp_get_one_sb_msg(mgr, true);
2036
2037 if (mgr->up_req_recv.have_eomt) {
2038 struct drm_dp_sideband_msg_req_body msg;
2039 struct drm_dp_mst_branch *mstb;
2040 bool seqno;
2041 mstb = drm_dp_get_mst_branch_device(mgr,
2042 mgr->up_req_recv.initial_hdr.lct,
2043 mgr->up_req_recv.initial_hdr.rad);
2044 if (!mstb) {
2045 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct);
2046 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2047 return 0;
2048 }
2049
2050 seqno = mgr->up_req_recv.initial_hdr.seqno;
2051 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg);
2052
2053 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
2054 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2055 drm_dp_update_port(mstb, &msg.u.conn_stat);
2056 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);
2057 (*mgr->cbs->hotplug)(mgr);
2058
2059 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
2060 drm_dp_send_up_ack_reply(mgr, mstb, msg.req_type, seqno, false);
2061 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn);
2062 }
2063
2064 drm_dp_put_mst_branch_device(mstb);
2065 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx));
2066 }
2067 return ret;
2068}
2069
2070/**
2071 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify
2072 * @mgr: manager to notify irq for.
2073 * @esi: 4 bytes from SINK_COUNT_ESI
2074 *
2075 * This should be called from the driver when it detects a short IRQ,
2076 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The
2077 * topology manager will process the sideband messages received as a result
2078 * of this.
2079 */
2080int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled)
2081{
2082 int ret = 0;
2083 int sc;
2084 *handled = false;
2085 sc = esi[0] & 0x3f;
2086
2087 if (sc != mgr->sink_count) {
2088 mgr->sink_count = sc;
2089 *handled = true;
2090 }
2091
2092 if (esi[1] & DP_DOWN_REP_MSG_RDY) {
2093 ret = drm_dp_mst_handle_down_rep(mgr);
2094 *handled = true;
2095 }
2096
2097 if (esi[1] & DP_UP_REQ_MSG_RDY) {
2098 ret |= drm_dp_mst_handle_up_req(mgr);
2099 *handled = true;
2100 }
2101
2102 drm_dp_mst_kick_tx(mgr);
2103 return ret;
2104}
2105EXPORT_SYMBOL(drm_dp_mst_hpd_irq);
2106
2107/**
2108 * drm_dp_mst_detect_port() - get connection status for an MST port
2109 * @mgr: manager for this port
2110 * @port: unverified pointer to a port
2111 *
2112 * This returns the current connection state for a port. It validates the
2113 * port pointer still exists so the caller doesn't require a reference
2114 */
2115enum drm_connector_status drm_dp_mst_detect_port(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2116{
2117 enum drm_connector_status status = connector_status_disconnected;
2118
2119 /* we need to search for the port in the mgr in case its gone */
2120 port = drm_dp_get_validated_port_ref(mgr, port);
2121 if (!port)
2122 return connector_status_disconnected;
2123
2124 if (!port->ddps)
2125 goto out;
2126
2127 switch (port->pdt) {
2128 case DP_PEER_DEVICE_NONE:
2129 case DP_PEER_DEVICE_MST_BRANCHING:
2130 break;
2131
2132 case DP_PEER_DEVICE_SST_SINK:
2133 status = connector_status_connected;
2134 break;
2135 case DP_PEER_DEVICE_DP_LEGACY_CONV:
2136 if (port->ldps)
2137 status = connector_status_connected;
2138 break;
2139 }
2140out:
2141 drm_dp_put_port(port);
2142 return status;
2143}
2144EXPORT_SYMBOL(drm_dp_mst_detect_port);
2145
2146/**
2147 * drm_dp_mst_get_edid() - get EDID for an MST port
2148 * @connector: toplevel connector to get EDID for
2149 * @mgr: manager for this port
2150 * @port: unverified pointer to a port.
2151 *
2152 * This returns an EDID for the port connected to a connector,
2153 * It validates the pointer still exists so the caller doesn't require a
2154 * reference.
2155 */
2156struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2157{
2158 struct edid *edid = NULL;
2159
2160 /* we need to search for the port in the mgr in case its gone */
2161 port = drm_dp_get_validated_port_ref(mgr, port);
2162 if (!port)
2163 return NULL;
2164
2165 edid = drm_get_edid(connector, &port->aux.ddc);
2166 drm_dp_put_port(port);
2167 return edid;
2168}
2169EXPORT_SYMBOL(drm_dp_mst_get_edid);
2170
2171/**
2172 * drm_dp_find_vcpi_slots() - find slots for this PBN value
2173 * @mgr: manager to use
2174 * @pbn: payload bandwidth to convert into slots.
2175 */
2176int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
2177 int pbn)
2178{
2179 int num_slots;
2180
2181 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2182
2183 if (num_slots > mgr->avail_slots)
2184 return -ENOSPC;
2185 return num_slots;
2186}
2187EXPORT_SYMBOL(drm_dp_find_vcpi_slots);
2188
2189static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr,
2190 struct drm_dp_vcpi *vcpi, int pbn)
2191{
2192 int num_slots;
2193 int ret;
2194
2195 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div);
2196
2197 if (num_slots > mgr->avail_slots)
2198 return -ENOSPC;
2199
2200 vcpi->pbn = pbn;
2201 vcpi->aligned_pbn = num_slots * mgr->pbn_div;
2202 vcpi->num_slots = num_slots;
2203
2204 ret = drm_dp_mst_assign_payload_id(mgr, vcpi);
2205 if (ret < 0)
2206 return ret;
2207 return 0;
2208}
2209
2210/**
2211 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel
2212 * @mgr: manager for this port
2213 * @port: port to allocate a virtual channel for.
2214 * @pbn: payload bandwidth number to request
2215 * @slots: returned number of slots for this PBN.
2216 */
2217bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots)
2218{
2219 int ret;
2220
2221 port = drm_dp_get_validated_port_ref(mgr, port);
2222 if (!port)
2223 return false;
2224
2225 if (port->vcpi.vcpi > 0) {
2226 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn);
2227 if (pbn == port->vcpi.pbn) {
2228 *slots = port->vcpi.num_slots;
2229 return true;
2230 }
2231 }
2232
2233 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn);
2234 if (ret) {
2235 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret);
2236 goto out;
2237 }
2238 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots);
2239 *slots = port->vcpi.num_slots;
2240
2241 drm_dp_put_port(port);
2242 return true;
2243out:
2244 return false;
2245}
2246EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi);
2247
2248/**
2249 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI
2250 * @mgr: manager for this port
2251 * @port: unverified pointer to a port.
2252 *
2253 * This just resets the number of slots for the ports VCPI for later programming.
2254 */
2255void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2256{
2257 port = drm_dp_get_validated_port_ref(mgr, port);
2258 if (!port)
2259 return;
2260 port->vcpi.num_slots = 0;
2261 drm_dp_put_port(port);
2262}
2263EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
2264
2265/**
2266 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI
2267 * @mgr: manager for this port
2268 * @port: unverified port to deallocate vcpi for
2269 */
2270void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
2271{
2272 port = drm_dp_get_validated_port_ref(mgr, port);
2273 if (!port)
2274 return;
2275
2276 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
2277 port->vcpi.num_slots = 0;
2278 port->vcpi.pbn = 0;
2279 port->vcpi.aligned_pbn = 0;
2280 port->vcpi.vcpi = 0;
2281 drm_dp_put_port(port);
2282}
2283EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi);
2284
2285static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,
2286 int id, struct drm_dp_payload *payload)
2287{
2288 u8 payload_alloc[3], status;
2289 int ret;
2290 int retries = 0;
2291
2292 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,
2293 DP_PAYLOAD_TABLE_UPDATED);
2294
2295 payload_alloc[0] = id;
2296 payload_alloc[1] = payload->start_slot;
2297 payload_alloc[2] = payload->num_slots;
2298
2299 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);
2300 if (ret != 3) {
2301 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret);
2302 goto fail;
2303 }
2304
2305retry:
2306 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2307 if (ret < 0) {
2308 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2309 goto fail;
2310 }
2311
2312 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {
2313 retries++;
2314 if (retries < 20) {
2315 usleep_range(10000, 20000);
2316 goto retry;
2317 }
2318 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status);
2319 ret = -EINVAL;
2320 goto fail;
2321 }
2322 ret = 0;
2323fail:
2324 return ret;
2325}
2326
2327
2328/**
2329 * drm_dp_check_act_status() - Check ACT handled status.
2330 * @mgr: manager to use
2331 *
2332 * Check the payload status bits in the DPCD for ACT handled completion.
2333 */
2334int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
2335{
2336 u8 status;
2337 int ret;
2338 int count = 0;
2339
2340 do {
2341 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
2342
2343 if (ret < 0) {
2344 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret);
2345 goto fail;
2346 }
2347
2348 if (status & DP_PAYLOAD_ACT_HANDLED)
2349 break;
2350 count++;
2351 udelay(100);
2352
2353 } while (count < 30);
2354
2355 if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
2356 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count);
2357 ret = -EINVAL;
2358 goto fail;
2359 }
2360 return 0;
2361fail:
2362 return ret;
2363}
2364EXPORT_SYMBOL(drm_dp_check_act_status);
2365
2366/**
2367 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode.
2368 * @clock: dot clock for the mode
2369 * @bpp: bpp for the mode.
2370 *
2371 * This uses the formula in the spec to calculate the PBN value for a mode.
2372 */
2373int drm_dp_calc_pbn_mode(int clock, int bpp)
2374{
2375 fixed20_12 pix_bw;
2376 fixed20_12 fbpp;
2377 fixed20_12 result;
2378 fixed20_12 margin, tmp;
2379 u32 res;
2380
2381 pix_bw.full = dfixed_const(clock);
2382 fbpp.full = dfixed_const(bpp);
2383 tmp.full = dfixed_const(8);
2384 fbpp.full = dfixed_div(fbpp, tmp);
2385
2386 result.full = dfixed_mul(pix_bw, fbpp);
2387 margin.full = dfixed_const(54);
2388 tmp.full = dfixed_const(64);
2389 margin.full = dfixed_div(margin, tmp);
2390 result.full = dfixed_div(result, margin);
2391
2392 margin.full = dfixed_const(1006);
2393 tmp.full = dfixed_const(1000);
2394 margin.full = dfixed_div(margin, tmp);
2395 result.full = dfixed_mul(result, margin);
2396
2397 result.full = dfixed_div(result, tmp);
2398 result.full = dfixed_ceil(result);
2399 res = dfixed_trunc(result);
2400 return res;
2401}
2402EXPORT_SYMBOL(drm_dp_calc_pbn_mode);
2403
2404static int test_calc_pbn_mode(void)
2405{
2406 int ret;
2407 ret = drm_dp_calc_pbn_mode(154000, 30);
2408 if (ret != 689)
2409 return -EINVAL;
2410 ret = drm_dp_calc_pbn_mode(234000, 30);
2411 if (ret != 1047)
2412 return -EINVAL;
2413 return 0;
2414}
2415
2416/* we want to kick the TX after we've ack the up/down IRQs. */
2417static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr)
2418{
2419 queue_work(system_long_wq, &mgr->tx_work);
2420}
2421
2422static void drm_dp_mst_dump_mstb(struct seq_file *m,
2423 struct drm_dp_mst_branch *mstb)
2424{
2425 struct drm_dp_mst_port *port;
2426 int tabs = mstb->lct;
2427 char prefix[10];
2428 int i;
2429
2430 for (i = 0; i < tabs; i++)
2431 prefix[i] = '\t';
2432 prefix[i] = '\0';
2433
2434 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports);
2435 list_for_each_entry(port, &mstb->ports, next) {
2436 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector);
2437 if (port->mstb)
2438 drm_dp_mst_dump_mstb(m, port->mstb);
2439 }
2440}
2441
2442static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr,
2443 char *buf)
2444{
2445 int ret;
2446 int i;
2447 for (i = 0; i < 4; i++) {
2448 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16);
2449 if (ret != 16)
2450 break;
2451 }
2452 if (i == 4)
2453 return true;
2454 return false;
2455}
2456
2457/**
2458 * drm_dp_mst_dump_topology(): dump topology to seq file.
2459 * @m: seq_file to dump output to
2460 * @mgr: manager to dump current topology for.
2461 *
2462 * helper to dump MST topology to a seq file for debugfs.
2463 */
2464void drm_dp_mst_dump_topology(struct seq_file *m,
2465 struct drm_dp_mst_topology_mgr *mgr)
2466{
2467 int i;
2468 struct drm_dp_mst_port *port;
2469 mutex_lock(&mgr->lock);
2470 if (mgr->mst_primary)
2471 drm_dp_mst_dump_mstb(m, mgr->mst_primary);
2472
2473 /* dump VCPIs */
2474 mutex_unlock(&mgr->lock);
2475
2476 mutex_lock(&mgr->payload_lock);
2477 seq_printf(m, "vcpi: %lx\n", mgr->payload_mask);
2478
2479 for (i = 0; i < mgr->max_payloads; i++) {
2480 if (mgr->proposed_vcpis[i]) {
2481 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
2482 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots);
2483 } else
2484 seq_printf(m, "vcpi %d:unsed\n", i);
2485 }
2486 for (i = 0; i < mgr->max_payloads; i++) {
2487 seq_printf(m, "payload %d: %d, %d, %d\n",
2488 i,
2489 mgr->payloads[i].payload_state,
2490 mgr->payloads[i].start_slot,
2491 mgr->payloads[i].num_slots);
2492
2493
2494 }
2495 mutex_unlock(&mgr->payload_lock);
2496
2497 mutex_lock(&mgr->lock);
2498 if (mgr->mst_primary) {
2499 u8 buf[64];
2500 bool bret;
2501 int ret;
2502 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE);
2503 seq_printf(m, "dpcd: ");
2504 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++)
2505 seq_printf(m, "%02x ", buf[i]);
2506 seq_printf(m, "\n");
2507 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2);
2508 seq_printf(m, "faux/mst: ");
2509 for (i = 0; i < 2; i++)
2510 seq_printf(m, "%02x ", buf[i]);
2511 seq_printf(m, "\n");
2512 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1);
2513 seq_printf(m, "mst ctrl: ");
2514 for (i = 0; i < 1; i++)
2515 seq_printf(m, "%02x ", buf[i]);
2516 seq_printf(m, "\n");
2517
2518 bret = dump_dp_payload_table(mgr, buf);
2519 if (bret == true) {
2520 seq_printf(m, "payload table: ");
2521 for (i = 0; i < 63; i++)
2522 seq_printf(m, "%02x ", buf[i]);
2523 seq_printf(m, "\n");
2524 }
2525
2526 }
2527
2528 mutex_unlock(&mgr->lock);
2529
2530}
2531EXPORT_SYMBOL(drm_dp_mst_dump_topology);
2532
2533static void drm_dp_tx_work(struct work_struct *work)
2534{
2535 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
2536
2537 mutex_lock(&mgr->qlock);
2538 if (mgr->tx_down_in_progress)
2539 process_single_down_tx_qlock(mgr);
2540 mutex_unlock(&mgr->qlock);
2541}
2542
2543/**
2544 * drm_dp_mst_topology_mgr_init - initialise a topology manager
2545 * @mgr: manager struct to initialise
2546 * @dev: device providing this structure - for i2c addition.
2547 * @aux: DP helper aux channel to talk to this device
2548 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit
2549 * @max_payloads: maximum number of payloads this GPU can source
2550 * @conn_base_id: the connector object ID the MST device is connected to.
2551 *
2552 * Return 0 for success, or negative error code on failure
2553 */
2554int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
2555 struct device *dev, struct drm_dp_aux *aux,
2556 int max_dpcd_transaction_bytes,
2557 int max_payloads, int conn_base_id)
2558{
2559 mutex_init(&mgr->lock);
2560 mutex_init(&mgr->qlock);
2561 mutex_init(&mgr->payload_lock);
2562 INIT_LIST_HEAD(&mgr->tx_msg_upq);
2563 INIT_LIST_HEAD(&mgr->tx_msg_downq);
2564 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);
2565 INIT_WORK(&mgr->tx_work, drm_dp_tx_work);
2566 init_waitqueue_head(&mgr->tx_waitq);
2567 mgr->dev = dev;
2568 mgr->aux = aux;
2569 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes;
2570 mgr->max_payloads = max_payloads;
2571 mgr->conn_base_id = conn_base_id;
2572 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL);
2573 if (!mgr->payloads)
2574 return -ENOMEM;
2575 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL);
2576 if (!mgr->proposed_vcpis)
2577 return -ENOMEM;
2578 set_bit(0, &mgr->payload_mask);
2579 test_calc_pbn_mode();
2580 return 0;
2581}
2582EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);
2583
2584/**
2585 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager.
2586 * @mgr: manager to destroy
2587 */
2588void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr)
2589{
2590 mutex_lock(&mgr->payload_lock);
2591 kfree(mgr->payloads);
2592 mgr->payloads = NULL;
2593 kfree(mgr->proposed_vcpis);
2594 mgr->proposed_vcpis = NULL;
2595 mutex_unlock(&mgr->payload_lock);
2596 mgr->dev = NULL;
2597 mgr->aux = NULL;
2598}
2599EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy);
2600
2601/* I2C device */
2602static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
2603 int num)
2604{
2605 struct drm_dp_aux *aux = adapter->algo_data;
2606 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux);
2607 struct drm_dp_mst_branch *mstb;
2608 struct drm_dp_mst_topology_mgr *mgr = port->mgr;
2609 unsigned int i;
2610 bool reading = false;
2611 struct drm_dp_sideband_msg_req_body msg;
2612 struct drm_dp_sideband_msg_tx *txmsg = NULL;
2613 int ret;
2614
2615 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
2616 if (!mstb)
2617 return -EREMOTEIO;
2618
2619 /* construct i2c msg */
2620 /* see if last msg is a read */
2621 if (msgs[num - 1].flags & I2C_M_RD)
2622 reading = true;
2623
2624 if (!reading) {
2625 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n");
2626 ret = -EIO;
2627 goto out;
2628 }
2629
2630 msg.req_type = DP_REMOTE_I2C_READ;
2631 msg.u.i2c_read.num_transactions = num - 1;
2632 msg.u.i2c_read.port_number = port->port_num;
2633 for (i = 0; i < num - 1; i++) {
2634 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr;
2635 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len;
2636 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf;
2637 }
2638 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr;
2639 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len;
2640
2641 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
2642 if (!txmsg) {
2643 ret = -ENOMEM;
2644 goto out;
2645 }
2646
2647 txmsg->dst = mstb;
2648 drm_dp_encode_sideband_req(&msg, txmsg);
2649
2650 drm_dp_queue_down_tx(mgr, txmsg);
2651
2652 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
2653 if (ret > 0) {
2654
2655 if (txmsg->reply.reply_type == 1) { /* got a NAK back */
2656 ret = -EREMOTEIO;
2657 goto out;
2658 }
2659 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) {
2660 ret = -EIO;
2661 goto out;
2662 }
2663 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len);
2664 ret = num;
2665 }
2666out:
2667 kfree(txmsg);
2668 drm_dp_put_mst_branch_device(mstb);
2669 return ret;
2670}
2671
2672static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter)
2673{
2674 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
2675 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
2676 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
2677 I2C_FUNC_10BIT_ADDR;
2678}
2679
2680static const struct i2c_algorithm drm_dp_mst_i2c_algo = {
2681 .functionality = drm_dp_mst_i2c_functionality,
2682 .master_xfer = drm_dp_mst_i2c_xfer,
2683};
2684
2685/**
2686 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX
2687 * @aux: DisplayPort AUX channel
2688 *
2689 * Returns 0 on success or a negative error code on failure.
2690 */
2691static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux)
2692{
2693 aux->ddc.algo = &drm_dp_mst_i2c_algo;
2694 aux->ddc.algo_data = aux;
2695 aux->ddc.retries = 3;
2696
2697 aux->ddc.class = I2C_CLASS_DDC;
2698 aux->ddc.owner = THIS_MODULE;
2699 aux->ddc.dev.parent = aux->dev;
2700 aux->ddc.dev.of_node = aux->dev->of_node;
2701
2702 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev),
2703 sizeof(aux->ddc.name));
2704
2705 return i2c_add_adapter(&aux->ddc);
2706}
2707
2708/**
2709 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter
2710 * @aux: DisplayPort AUX channel
2711 */
2712static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux)
2713{
2714 i2c_del_adapter(&aux->ddc);
2715}
generated by cgit v1.2.2 (git 2.25.0) at 2025-06-12 10:38:56 -0400