1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2020-2021 Intel Corporation
4 */
5
6#include "i915_drv.h"
7#include "i915_reg.h"
8#include "i915_trace.h"
9#include "intel_bios.h"
10#include "intel_de.h"
11#include "intel_display_types.h"
12#include "intel_dp.h"
13#include "intel_dp_aux.h"
14#include "intel_dp_aux_regs.h"
15#include "intel_pps.h"
16#include "intel_tc.h"
17
18#define AUX_CH_NAME_BUFSIZE 6
19
20static const char *aux_ch_name(struct drm_i915_private *i915,
21 char *buf, int size, enum aux_ch aux_ch)
22{
23 if (DISPLAY_VER(i915) >= 13 && aux_ch >= AUX_CH_D_XELPD)
24 snprintf(buf, size, fmt: "%c", 'A' + aux_ch - AUX_CH_D_XELPD + AUX_CH_D);
25 else if (DISPLAY_VER(i915) >= 12 && aux_ch >= AUX_CH_USBC1)
26 snprintf(buf, size, fmt: "USBC%c", '1' + aux_ch - AUX_CH_USBC1);
27 else
28 snprintf(buf, size, fmt: "%c", 'A' + aux_ch);
29
30 return buf;
31}
32
33u32 intel_dp_aux_pack(const u8 *src, int src_bytes)
34{
35 int i;
36 u32 v = 0;
37
38 if (src_bytes > 4)
39 src_bytes = 4;
40 for (i = 0; i < src_bytes; i++)
41 v |= ((u32)src[i]) << ((3 - i) * 8);
42 return v;
43}
44
45static void intel_dp_aux_unpack(u32 src, u8 *dst, int dst_bytes)
46{
47 int i;
48
49 if (dst_bytes > 4)
50 dst_bytes = 4;
51 for (i = 0; i < dst_bytes; i++)
52 dst[i] = src >> ((3 - i) * 8);
53}
54
55static u32
56intel_dp_aux_wait_done(struct intel_dp *intel_dp)
57{
58 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
59 i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
60 const unsigned int timeout_ms = 10;
61 u32 status;
62 int ret;
63
64 ret = __intel_de_wait_for_register(i915, reg: ch_ctl,
65 DP_AUX_CH_CTL_SEND_BUSY, value: 0,
66 fast_timeout_us: 2, slow_timeout_ms: timeout_ms, out_value: &status);
67
68 if (ret == -ETIMEDOUT)
69 drm_err(&i915->drm,
70 "%s: did not complete or timeout within %ums (status 0x%08x)\n",
71 intel_dp->aux.name, timeout_ms, status);
72
73 return status;
74}
75
76static u32 g4x_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
77{
78 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
79
80 if (index)
81 return 0;
82
83 /*
84 * The clock divider is based off the hrawclk, and would like to run at
85 * 2MHz. So, take the hrawclk value and divide by 2000 and use that
86 */
87 return DIV_ROUND_CLOSEST(RUNTIME_INFO(i915)->rawclk_freq, 2000);
88}
89
90static u32 ilk_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
91{
92 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
93 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
94 u32 freq;
95
96 if (index)
97 return 0;
98
99 /*
100 * The clock divider is based off the cdclk or PCH rawclk, and would
101 * like to run at 2MHz. So, take the cdclk or PCH rawclk value and
102 * divide by 2000 and use that
103 */
104 if (dig_port->aux_ch == AUX_CH_A)
105 freq = i915->display.cdclk.hw.cdclk;
106 else
107 freq = RUNTIME_INFO(i915)->rawclk_freq;
108 return DIV_ROUND_CLOSEST(freq, 2000);
109}
110
111static u32 hsw_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
112{
113 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
114 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
115
116 if (dig_port->aux_ch != AUX_CH_A && HAS_PCH_LPT_H(i915)) {
117 /* Workaround for non-ULT HSW */
118 switch (index) {
119 case 0: return 63;
120 case 1: return 72;
121 default: return 0;
122 }
123 }
124
125 return ilk_get_aux_clock_divider(intel_dp, index);
126}
127
128static u32 skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
129{
130 /*
131 * SKL doesn't need us to program the AUX clock divider (Hardware will
132 * derive the clock from CDCLK automatically). We still implement the
133 * get_aux_clock_divider vfunc to plug-in into the existing code.
134 */
135 return index ? 0 : 1;
136}
137
138static int intel_dp_aux_sync_len(void)
139{
140 int precharge = 16; /* 10-16 */
141 int preamble = 16;
142
143 return precharge + preamble;
144}
145
146static int intel_dp_aux_fw_sync_len(void)
147{
148 int precharge = 10; /* 10-16 */
149 int preamble = 8;
150
151 return precharge + preamble;
152}
153
154static int g4x_dp_aux_precharge_len(void)
155{
156 int precharge_min = 10;
157 int preamble = 16;
158
159 /* HW wants the length of the extra precharge in 2us units */
160 return (intel_dp_aux_sync_len() -
161 precharge_min - preamble) / 2;
162}
163
164static u32 g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
165 int send_bytes,
166 u32 aux_clock_divider)
167{
168 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
169 struct drm_i915_private *i915 = to_i915(dev: dig_port->base.base.dev);
170 u32 timeout;
171
172 /* Max timeout value on G4x-BDW: 1.6ms */
173 if (IS_BROADWELL(i915))
174 timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
175 else
176 timeout = DP_AUX_CH_CTL_TIME_OUT_400us;
177
178 return DP_AUX_CH_CTL_SEND_BUSY |
179 DP_AUX_CH_CTL_DONE |
180 DP_AUX_CH_CTL_INTERRUPT |
181 DP_AUX_CH_CTL_TIME_OUT_ERROR |
182 timeout |
183 DP_AUX_CH_CTL_RECEIVE_ERROR |
184 DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
185 DP_AUX_CH_CTL_PRECHARGE_2US(g4x_dp_aux_precharge_len()) |
186 DP_AUX_CH_CTL_BIT_CLOCK_2X(aux_clock_divider);
187}
188
189static u32 skl_get_aux_send_ctl(struct intel_dp *intel_dp,
190 int send_bytes,
191 u32 unused)
192{
193 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
194 struct drm_i915_private *i915 = to_i915(dev: dig_port->base.base.dev);
195 u32 ret;
196
197 /*
198 * Max timeout values:
199 * SKL-GLK: 1.6ms
200 * ICL+: 4ms
201 */
202 ret = DP_AUX_CH_CTL_SEND_BUSY |
203 DP_AUX_CH_CTL_DONE |
204 DP_AUX_CH_CTL_INTERRUPT |
205 DP_AUX_CH_CTL_TIME_OUT_ERROR |
206 DP_AUX_CH_CTL_TIME_OUT_MAX |
207 DP_AUX_CH_CTL_RECEIVE_ERROR |
208 DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
209 DP_AUX_CH_CTL_FW_SYNC_PULSE_SKL(intel_dp_aux_fw_sync_len()) |
210 DP_AUX_CH_CTL_SYNC_PULSE_SKL(intel_dp_aux_sync_len());
211
212 if (intel_tc_port_in_tbt_alt_mode(dig_port))
213 ret |= DP_AUX_CH_CTL_TBT_IO;
214
215 /*
216 * Power request bit is already set during aux power well enable.
217 * Preserve the bit across aux transactions.
218 */
219 if (DISPLAY_VER(i915) >= 14)
220 ret |= XELPDP_DP_AUX_CH_CTL_POWER_REQUEST;
221
222 return ret;
223}
224
225static int
226intel_dp_aux_xfer(struct intel_dp *intel_dp,
227 const u8 *send, int send_bytes,
228 u8 *recv, int recv_size,
229 u32 aux_send_ctl_flags)
230{
231 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
232 struct intel_encoder *encoder = &dig_port->base;
233 struct drm_i915_private *i915 = to_i915(dev: dig_port->base.base.dev);
234 i915_reg_t ch_ctl, ch_data[5];
235 u32 aux_clock_divider;
236 enum intel_display_power_domain aux_domain;
237 intel_wakeref_t aux_wakeref;
238 intel_wakeref_t pps_wakeref;
239 int i, ret, recv_bytes;
240 int try, clock = 0;
241 u32 status;
242 bool vdd;
243
244 ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
245 for (i = 0; i < ARRAY_SIZE(ch_data); i++)
246 ch_data[i] = intel_dp->aux_ch_data_reg(intel_dp, i);
247
248 intel_digital_port_lock(encoder);
249 /*
250 * Abort transfers on a disconnected port as required by
251 * DP 1.4a link CTS 4.2.1.5, also avoiding the long AUX
252 * timeouts that would otherwise happen.
253 */
254 if (!intel_dp_is_edp(intel_dp) &&
255 !intel_digital_port_connected_locked(encoder: &dig_port->base)) {
256 ret = -ENXIO;
257 goto out_unlock;
258 }
259
260 aux_domain = intel_aux_power_domain(dig_port);
261
262 aux_wakeref = intel_display_power_get(dev_priv: i915, domain: aux_domain);
263 pps_wakeref = intel_pps_lock(intel_dp);
264
265 /*
266 * We will be called with VDD already enabled for dpcd/edid/oui reads.
267 * In such cases we want to leave VDD enabled and it's up to upper layers
268 * to turn it off. But for eg. i2c-dev access we need to turn it on/off
269 * ourselves.
270 */
271 vdd = intel_pps_vdd_on_unlocked(intel_dp);
272
273 /*
274 * dp aux is extremely sensitive to irq latency, hence request the
275 * lowest possible wakeup latency and so prevent the cpu from going into
276 * deep sleep states.
277 */
278 cpu_latency_qos_update_request(req: &intel_dp->pm_qos, new_value: 0);
279
280 intel_pps_check_power_unlocked(intel_dp);
281
282 /*
283 * FIXME PSR should be disabled here to prevent
284 * it using the same AUX CH simultaneously
285 */
286
287 /* Try to wait for any previous AUX channel activity */
288 for (try = 0; try < 3; try++) {
289 status = intel_de_read_notrace(i915, reg: ch_ctl);
290 if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
291 break;
292 msleep(msecs: 1);
293 }
294 /* just trace the final value */
295 trace_i915_reg_rw(write: false, reg: ch_ctl, val: status, len: sizeof(status), trace: true);
296
297 if (try == 3) {
298 const u32 status = intel_de_read(i915, reg: ch_ctl);
299
300 if (status != intel_dp->aux_busy_last_status) {
301 drm_WARN(&i915->drm, 1,
302 "%s: not started (status 0x%08x)\n",
303 intel_dp->aux.name, status);
304 intel_dp->aux_busy_last_status = status;
305 }
306
307 ret = -EBUSY;
308 goto out;
309 }
310
311 /* Only 5 data registers! */
312 if (drm_WARN_ON(&i915->drm, send_bytes > 20 || recv_size > 20)) {
313 ret = -E2BIG;
314 goto out;
315 }
316
317 while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
318 u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
319 send_bytes,
320 aux_clock_divider);
321
322 send_ctl |= aux_send_ctl_flags;
323
324 /* Must try at least 3 times according to DP spec */
325 for (try = 0; try < 5; try++) {
326 /* Load the send data into the aux channel data registers */
327 for (i = 0; i < send_bytes; i += 4)
328 intel_de_write(i915, reg: ch_data[i >> 2],
329 val: intel_dp_aux_pack(src: send + i,
330 src_bytes: send_bytes - i));
331
332 /* Send the command and wait for it to complete */
333 intel_de_write(i915, reg: ch_ctl, val: send_ctl);
334
335 status = intel_dp_aux_wait_done(intel_dp);
336
337 /* Clear done status and any errors */
338 intel_de_write(i915, reg: ch_ctl,
339 val: status | DP_AUX_CH_CTL_DONE |
340 DP_AUX_CH_CTL_TIME_OUT_ERROR |
341 DP_AUX_CH_CTL_RECEIVE_ERROR);
342
343 /*
344 * DP CTS 1.2 Core Rev 1.1, 4.2.1.1 & 4.2.1.2
345 * 400us delay required for errors and timeouts
346 * Timeout errors from the HW already meet this
347 * requirement so skip to next iteration
348 */
349 if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR)
350 continue;
351
352 if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
353 usleep_range(min: 400, max: 500);
354 continue;
355 }
356 if (status & DP_AUX_CH_CTL_DONE)
357 goto done;
358 }
359 }
360
361 if ((status & DP_AUX_CH_CTL_DONE) == 0) {
362 drm_err(&i915->drm, "%s: not done (status 0x%08x)\n",
363 intel_dp->aux.name, status);
364 ret = -EBUSY;
365 goto out;
366 }
367
368done:
369 /*
370 * Check for timeout or receive error. Timeouts occur when the sink is
371 * not connected.
372 */
373 if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
374 drm_err(&i915->drm, "%s: receive error (status 0x%08x)\n",
375 intel_dp->aux.name, status);
376 ret = -EIO;
377 goto out;
378 }
379
380 /*
381 * Timeouts occur when the device isn't connected, so they're "normal"
382 * -- don't fill the kernel log with these
383 */
384 if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
385 drm_dbg_kms(&i915->drm, "%s: timeout (status 0x%08x)\n",
386 intel_dp->aux.name, status);
387 ret = -ETIMEDOUT;
388 goto out;
389 }
390
391 /* Unload any bytes sent back from the other side */
392 recv_bytes = REG_FIELD_GET(DP_AUX_CH_CTL_MESSAGE_SIZE_MASK, status);
393
394 /*
395 * By BSpec: "Message sizes of 0 or >20 are not allowed."
396 * We have no idea of what happened so we return -EBUSY so
397 * drm layer takes care for the necessary retries.
398 */
399 if (recv_bytes == 0 || recv_bytes > 20) {
400 drm_dbg_kms(&i915->drm,
401 "%s: Forbidden recv_bytes = %d on aux transaction\n",
402 intel_dp->aux.name, recv_bytes);
403 ret = -EBUSY;
404 goto out;
405 }
406
407 if (recv_bytes > recv_size)
408 recv_bytes = recv_size;
409
410 for (i = 0; i < recv_bytes; i += 4)
411 intel_dp_aux_unpack(src: intel_de_read(i915, reg: ch_data[i >> 2]),
412 dst: recv + i, dst_bytes: recv_bytes - i);
413
414 ret = recv_bytes;
415out:
416 cpu_latency_qos_update_request(req: &intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
417
418 if (vdd)
419 intel_pps_vdd_off_unlocked(intel_dp, sync: false);
420
421 intel_pps_unlock(intel_dp, wakeref: pps_wakeref);
422 intel_display_power_put_async(i915, domain: aux_domain, wakeref: aux_wakeref);
423out_unlock:
424 intel_digital_port_unlock(encoder);
425
426 return ret;
427}
428
429#define BARE_ADDRESS_SIZE 3
430#define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
431
432static void
433intel_dp_aux_header(u8 txbuf[HEADER_SIZE],
434 const struct drm_dp_aux_msg *msg)
435{
436 txbuf[0] = (msg->request << 4) | ((msg->address >> 16) & 0xf);
437 txbuf[1] = (msg->address >> 8) & 0xff;
438 txbuf[2] = msg->address & 0xff;
439 txbuf[3] = msg->size - 1;
440}
441
442static u32 intel_dp_aux_xfer_flags(const struct drm_dp_aux_msg *msg)
443{
444 /*
445 * If we're trying to send the HDCP Aksv, we need to set a the Aksv
446 * select bit to inform the hardware to send the Aksv after our header
447 * since we can't access that data from software.
448 */
449 if ((msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_NATIVE_WRITE &&
450 msg->address == DP_AUX_HDCP_AKSV)
451 return DP_AUX_CH_CTL_AUX_AKSV_SELECT;
452
453 return 0;
454}
455
456static ssize_t
457intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
458{
459 struct intel_dp *intel_dp = container_of(aux, struct intel_dp, aux);
460 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
461 u8 txbuf[20], rxbuf[20];
462 size_t txsize, rxsize;
463 u32 flags = intel_dp_aux_xfer_flags(msg);
464 int ret;
465
466 intel_dp_aux_header(txbuf, msg);
467
468 switch (msg->request & ~DP_AUX_I2C_MOT) {
469 case DP_AUX_NATIVE_WRITE:
470 case DP_AUX_I2C_WRITE:
471 case DP_AUX_I2C_WRITE_STATUS_UPDATE:
472 txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
473 rxsize = 2; /* 0 or 1 data bytes */
474
475 if (drm_WARN_ON(&i915->drm, txsize > 20))
476 return -E2BIG;
477
478 drm_WARN_ON(&i915->drm, !msg->buffer != !msg->size);
479
480 if (msg->buffer)
481 memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);
482
483 ret = intel_dp_aux_xfer(intel_dp, send: txbuf, send_bytes: txsize,
484 recv: rxbuf, recv_size: rxsize, aux_send_ctl_flags: flags);
485 if (ret > 0) {
486 msg->reply = rxbuf[0] >> 4;
487
488 if (ret > 1) {
489 /* Number of bytes written in a short write. */
490 ret = clamp_t(int, rxbuf[1], 0, msg->size);
491 } else {
492 /* Return payload size. */
493 ret = msg->size;
494 }
495 }
496 break;
497
498 case DP_AUX_NATIVE_READ:
499 case DP_AUX_I2C_READ:
500 txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
501 rxsize = msg->size + 1;
502
503 if (drm_WARN_ON(&i915->drm, rxsize > 20))
504 return -E2BIG;
505
506 ret = intel_dp_aux_xfer(intel_dp, send: txbuf, send_bytes: txsize,
507 recv: rxbuf, recv_size: rxsize, aux_send_ctl_flags: flags);
508 if (ret > 0) {
509 msg->reply = rxbuf[0] >> 4;
510 /*
511 * Assume happy day, and copy the data. The caller is
512 * expected to check msg->reply before touching it.
513 *
514 * Return payload size.
515 */
516 ret--;
517 memcpy(msg->buffer, rxbuf + 1, ret);
518 }
519 break;
520
521 default:
522 ret = -EINVAL;
523 break;
524 }
525
526 return ret;
527}
528
529static i915_reg_t vlv_aux_ctl_reg(struct intel_dp *intel_dp)
530{
531 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
532 enum aux_ch aux_ch = dig_port->aux_ch;
533
534 switch (aux_ch) {
535 case AUX_CH_B:
536 case AUX_CH_C:
537 case AUX_CH_D:
538 return VLV_DP_AUX_CH_CTL(aux_ch);
539 default:
540 MISSING_CASE(aux_ch);
541 return VLV_DP_AUX_CH_CTL(AUX_CH_B);
542 }
543}
544
545static i915_reg_t vlv_aux_data_reg(struct intel_dp *intel_dp, int index)
546{
547 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
548 enum aux_ch aux_ch = dig_port->aux_ch;
549
550 switch (aux_ch) {
551 case AUX_CH_B:
552 case AUX_CH_C:
553 case AUX_CH_D:
554 return VLV_DP_AUX_CH_DATA(aux_ch, index);
555 default:
556 MISSING_CASE(aux_ch);
557 return VLV_DP_AUX_CH_DATA(AUX_CH_B, index);
558 }
559}
560
561static i915_reg_t g4x_aux_ctl_reg(struct intel_dp *intel_dp)
562{
563 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
564 enum aux_ch aux_ch = dig_port->aux_ch;
565
566 switch (aux_ch) {
567 case AUX_CH_B:
568 case AUX_CH_C:
569 case AUX_CH_D:
570 return DP_AUX_CH_CTL(aux_ch);
571 default:
572 MISSING_CASE(aux_ch);
573 return DP_AUX_CH_CTL(AUX_CH_B);
574 }
575}
576
577static i915_reg_t g4x_aux_data_reg(struct intel_dp *intel_dp, int index)
578{
579 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
580 enum aux_ch aux_ch = dig_port->aux_ch;
581
582 switch (aux_ch) {
583 case AUX_CH_B:
584 case AUX_CH_C:
585 case AUX_CH_D:
586 return DP_AUX_CH_DATA(aux_ch, index);
587 default:
588 MISSING_CASE(aux_ch);
589 return DP_AUX_CH_DATA(AUX_CH_B, index);
590 }
591}
592
593static i915_reg_t ilk_aux_ctl_reg(struct intel_dp *intel_dp)
594{
595 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
596 enum aux_ch aux_ch = dig_port->aux_ch;
597
598 switch (aux_ch) {
599 case AUX_CH_A:
600 return DP_AUX_CH_CTL(aux_ch);
601 case AUX_CH_B:
602 case AUX_CH_C:
603 case AUX_CH_D:
604 return PCH_DP_AUX_CH_CTL(aux_ch);
605 default:
606 MISSING_CASE(aux_ch);
607 return DP_AUX_CH_CTL(AUX_CH_A);
608 }
609}
610
611static i915_reg_t ilk_aux_data_reg(struct intel_dp *intel_dp, int index)
612{
613 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
614 enum aux_ch aux_ch = dig_port->aux_ch;
615
616 switch (aux_ch) {
617 case AUX_CH_A:
618 return DP_AUX_CH_DATA(aux_ch, index);
619 case AUX_CH_B:
620 case AUX_CH_C:
621 case AUX_CH_D:
622 return PCH_DP_AUX_CH_DATA(aux_ch, index);
623 default:
624 MISSING_CASE(aux_ch);
625 return DP_AUX_CH_DATA(AUX_CH_A, index);
626 }
627}
628
629static i915_reg_t skl_aux_ctl_reg(struct intel_dp *intel_dp)
630{
631 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
632 enum aux_ch aux_ch = dig_port->aux_ch;
633
634 switch (aux_ch) {
635 case AUX_CH_A:
636 case AUX_CH_B:
637 case AUX_CH_C:
638 case AUX_CH_D:
639 case AUX_CH_E:
640 case AUX_CH_F:
641 return DP_AUX_CH_CTL(aux_ch);
642 default:
643 MISSING_CASE(aux_ch);
644 return DP_AUX_CH_CTL(AUX_CH_A);
645 }
646}
647
648static i915_reg_t skl_aux_data_reg(struct intel_dp *intel_dp, int index)
649{
650 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
651 enum aux_ch aux_ch = dig_port->aux_ch;
652
653 switch (aux_ch) {
654 case AUX_CH_A:
655 case AUX_CH_B:
656 case AUX_CH_C:
657 case AUX_CH_D:
658 case AUX_CH_E:
659 case AUX_CH_F:
660 return DP_AUX_CH_DATA(aux_ch, index);
661 default:
662 MISSING_CASE(aux_ch);
663 return DP_AUX_CH_DATA(AUX_CH_A, index);
664 }
665}
666
667static i915_reg_t tgl_aux_ctl_reg(struct intel_dp *intel_dp)
668{
669 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
670 enum aux_ch aux_ch = dig_port->aux_ch;
671
672 switch (aux_ch) {
673 case AUX_CH_A:
674 case AUX_CH_B:
675 case AUX_CH_C:
676 case AUX_CH_USBC1:
677 case AUX_CH_USBC2:
678 case AUX_CH_USBC3:
679 case AUX_CH_USBC4:
680 case AUX_CH_USBC5: /* aka AUX_CH_D_XELPD */
681 case AUX_CH_USBC6: /* aka AUX_CH_E_XELPD */
682 return DP_AUX_CH_CTL(aux_ch);
683 default:
684 MISSING_CASE(aux_ch);
685 return DP_AUX_CH_CTL(AUX_CH_A);
686 }
687}
688
689static i915_reg_t tgl_aux_data_reg(struct intel_dp *intel_dp, int index)
690{
691 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
692 enum aux_ch aux_ch = dig_port->aux_ch;
693
694 switch (aux_ch) {
695 case AUX_CH_A:
696 case AUX_CH_B:
697 case AUX_CH_C:
698 case AUX_CH_USBC1:
699 case AUX_CH_USBC2:
700 case AUX_CH_USBC3:
701 case AUX_CH_USBC4:
702 case AUX_CH_USBC5: /* aka AUX_CH_D_XELPD */
703 case AUX_CH_USBC6: /* aka AUX_CH_E_XELPD */
704 return DP_AUX_CH_DATA(aux_ch, index);
705 default:
706 MISSING_CASE(aux_ch);
707 return DP_AUX_CH_DATA(AUX_CH_A, index);
708 }
709}
710
711static i915_reg_t xelpdp_aux_ctl_reg(struct intel_dp *intel_dp)
712{
713 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
714 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
715 enum aux_ch aux_ch = dig_port->aux_ch;
716
717 switch (aux_ch) {
718 case AUX_CH_A:
719 case AUX_CH_B:
720 case AUX_CH_USBC1:
721 case AUX_CH_USBC2:
722 case AUX_CH_USBC3:
723 case AUX_CH_USBC4:
724 return XELPDP_DP_AUX_CH_CTL(i915, aux_ch);
725 default:
726 MISSING_CASE(aux_ch);
727 return XELPDP_DP_AUX_CH_CTL(i915, AUX_CH_A);
728 }
729}
730
731static i915_reg_t xelpdp_aux_data_reg(struct intel_dp *intel_dp, int index)
732{
733 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
734 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
735 enum aux_ch aux_ch = dig_port->aux_ch;
736
737 switch (aux_ch) {
738 case AUX_CH_A:
739 case AUX_CH_B:
740 case AUX_CH_USBC1:
741 case AUX_CH_USBC2:
742 case AUX_CH_USBC3:
743 case AUX_CH_USBC4:
744 return XELPDP_DP_AUX_CH_DATA(i915, aux_ch, index);
745 default:
746 MISSING_CASE(aux_ch);
747 return XELPDP_DP_AUX_CH_DATA(i915, AUX_CH_A, index);
748 }
749}
750
751void intel_dp_aux_fini(struct intel_dp *intel_dp)
752{
753 if (cpu_latency_qos_request_active(req: &intel_dp->pm_qos))
754 cpu_latency_qos_remove_request(req: &intel_dp->pm_qos);
755
756 kfree(objp: intel_dp->aux.name);
757}
758
759void intel_dp_aux_init(struct intel_dp *intel_dp)
760{
761 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
762 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
763 struct intel_encoder *encoder = &dig_port->base;
764 enum aux_ch aux_ch = dig_port->aux_ch;
765 char buf[AUX_CH_NAME_BUFSIZE];
766
767 if (DISPLAY_VER(i915) >= 14) {
768 intel_dp->aux_ch_ctl_reg = xelpdp_aux_ctl_reg;
769 intel_dp->aux_ch_data_reg = xelpdp_aux_data_reg;
770 } else if (DISPLAY_VER(i915) >= 12) {
771 intel_dp->aux_ch_ctl_reg = tgl_aux_ctl_reg;
772 intel_dp->aux_ch_data_reg = tgl_aux_data_reg;
773 } else if (DISPLAY_VER(i915) >= 9) {
774 intel_dp->aux_ch_ctl_reg = skl_aux_ctl_reg;
775 intel_dp->aux_ch_data_reg = skl_aux_data_reg;
776 } else if (HAS_PCH_SPLIT(i915)) {
777 intel_dp->aux_ch_ctl_reg = ilk_aux_ctl_reg;
778 intel_dp->aux_ch_data_reg = ilk_aux_data_reg;
779 } else if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) {
780 intel_dp->aux_ch_ctl_reg = vlv_aux_ctl_reg;
781 intel_dp->aux_ch_data_reg = vlv_aux_data_reg;
782 } else {
783 intel_dp->aux_ch_ctl_reg = g4x_aux_ctl_reg;
784 intel_dp->aux_ch_data_reg = g4x_aux_data_reg;
785 }
786
787 if (DISPLAY_VER(i915) >= 9)
788 intel_dp->get_aux_clock_divider = skl_get_aux_clock_divider;
789 else if (IS_BROADWELL(i915) || IS_HASWELL(i915))
790 intel_dp->get_aux_clock_divider = hsw_get_aux_clock_divider;
791 else if (HAS_PCH_SPLIT(i915))
792 intel_dp->get_aux_clock_divider = ilk_get_aux_clock_divider;
793 else
794 intel_dp->get_aux_clock_divider = g4x_get_aux_clock_divider;
795
796 if (DISPLAY_VER(i915) >= 9)
797 intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
798 else
799 intel_dp->get_aux_send_ctl = g4x_get_aux_send_ctl;
800
801 intel_dp->aux.drm_dev = &i915->drm;
802 drm_dp_aux_init(aux: &intel_dp->aux);
803
804 /* Failure to allocate our preferred name is not critical */
805 intel_dp->aux.name = kasprintf(GFP_KERNEL, fmt: "AUX %s/%s",
806 aux_ch_name(i915, buf, size: sizeof(buf), aux_ch),
807 encoder->base.name);
808
809 intel_dp->aux.transfer = intel_dp_aux_transfer;
810 cpu_latency_qos_add_request(req: &intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
811}
812
813static enum aux_ch default_aux_ch(struct intel_encoder *encoder)
814{
815 struct drm_i915_private *i915 = to_i915(dev: encoder->base.dev);
816
817 /* SKL has DDI E but no AUX E */
818 if (DISPLAY_VER(i915) == 9 && encoder->port == PORT_E)
819 return AUX_CH_A;
820
821 return (enum aux_ch)encoder->port;
822}
823
824static struct intel_encoder *
825get_encoder_by_aux_ch(struct intel_encoder *encoder,
826 enum aux_ch aux_ch)
827{
828 struct drm_i915_private *i915 = to_i915(dev: encoder->base.dev);
829 struct intel_encoder *other;
830
831 for_each_intel_encoder(&i915->drm, other) {
832 if (other == encoder)
833 continue;
834
835 if (!intel_encoder_is_dig_port(encoder: other))
836 continue;
837
838 if (enc_to_dig_port(encoder: other)->aux_ch == aux_ch)
839 return other;
840 }
841
842 return NULL;
843}
844
845enum aux_ch intel_dp_aux_ch(struct intel_encoder *encoder)
846{
847 struct drm_i915_private *i915 = to_i915(dev: encoder->base.dev);
848 struct intel_encoder *other;
849 const char *source;
850 enum aux_ch aux_ch;
851 char buf[AUX_CH_NAME_BUFSIZE];
852
853 aux_ch = intel_bios_dp_aux_ch(devdata: encoder->devdata);
854 source = "VBT";
855
856 if (aux_ch == AUX_CH_NONE) {
857 aux_ch = default_aux_ch(encoder);
858 source = "platform default";
859 }
860
861 if (aux_ch == AUX_CH_NONE)
862 return AUX_CH_NONE;
863
864 /* FIXME validate aux_ch against platform caps */
865
866 other = get_encoder_by_aux_ch(encoder, aux_ch);
867 if (other) {
868 drm_dbg_kms(&i915->drm,
869 "[ENCODER:%d:%s] AUX CH %s already claimed by [ENCODER:%d:%s]\n",
870 encoder->base.base.id, encoder->base.name,
871 aux_ch_name(i915, buf, sizeof(buf), aux_ch),
872 other->base.base.id, other->base.name);
873 return AUX_CH_NONE;
874 }
875
876 drm_dbg_kms(&i915->drm,
877 "[ENCODER:%d:%s] Using AUX CH %s (%s)\n",
878 encoder->base.base.id, encoder->base.name,
879 aux_ch_name(i915, buf, sizeof(buf), aux_ch), source);
880
881 return aux_ch;
882}
883
884void intel_dp_aux_irq_handler(struct drm_i915_private *i915)
885{
886 wake_up_all(&i915->display.gmbus.wait_queue);
887}
888

source code of linux/drivers/gpu/drm/i915/display/intel_dp_aux.c