xref: /linux/drivers/gpu/drm/i915/display/intel_dp_aux.c (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020-2021 Intel Corporation
4  */
5 
6 #include <drm/drm_print.h>
7 
8 #include "i915_utils.h"
9 #include "intel_de.h"
10 #include "intel_display_types.h"
11 #include "intel_dp.h"
12 #include "intel_dp_aux.h"
13 #include "intel_dp_aux_regs.h"
14 #include "intel_pps.h"
15 #include "intel_quirks.h"
16 #include "intel_tc.h"
17 #include "intel_uncore_trace.h"
18 
19 #define AUX_CH_NAME_BUFSIZE	6
20 
aux_ch_name(struct intel_display * display,char * buf,int size,enum aux_ch aux_ch)21 static const char *aux_ch_name(struct intel_display *display,
22 			       char *buf, int size, enum aux_ch aux_ch)
23 {
24 	if (DISPLAY_VER(display) >= 13 && aux_ch >= AUX_CH_D_XELPD)
25 		snprintf(buf, size, "%c", 'A' + aux_ch - AUX_CH_D_XELPD + AUX_CH_D);
26 	else if (DISPLAY_VER(display) >= 12 && aux_ch >= AUX_CH_USBC1)
27 		snprintf(buf, size, "USBC%c", '1' + aux_ch - AUX_CH_USBC1);
28 	else
29 		snprintf(buf, size, "%c", 'A' + aux_ch);
30 
31 	return buf;
32 }
33 
intel_dp_aux_pack(const u8 * src,int src_bytes)34 u32 intel_dp_aux_pack(const u8 *src, int src_bytes)
35 {
36 	int i;
37 	u32 v = 0;
38 
39 	if (src_bytes > 4)
40 		src_bytes = 4;
41 	for (i = 0; i < src_bytes; i++)
42 		v |= ((u32)src[i]) << ((3 - i) * 8);
43 	return v;
44 }
45 
intel_dp_aux_unpack(u32 src,u8 * dst,int dst_bytes)46 static void intel_dp_aux_unpack(u32 src, u8 *dst, int dst_bytes)
47 {
48 	int i;
49 
50 	if (dst_bytes > 4)
51 		dst_bytes = 4;
52 	for (i = 0; i < dst_bytes; i++)
53 		dst[i] = src >> ((3 - i) * 8);
54 }
55 
56 static u32
intel_dp_aux_wait_done(struct intel_dp * intel_dp)57 intel_dp_aux_wait_done(struct intel_dp *intel_dp)
58 {
59 	struct intel_display *display = to_intel_display(intel_dp);
60 	i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
61 	const unsigned int timeout_ms = 10;
62 	u32 status;
63 	int ret;
64 
65 	ret = intel_de_wait_custom(display, ch_ctl, DP_AUX_CH_CTL_SEND_BUSY,
66 				   0,
67 				   2, timeout_ms, &status);
68 
69 	if (ret == -ETIMEDOUT)
70 		drm_err(display->drm,
71 			"%s: did not complete or timeout within %ums (status 0x%08x)\n",
72 			intel_dp->aux.name, timeout_ms, status);
73 
74 	return status;
75 }
76 
g4x_get_aux_clock_divider(struct intel_dp * intel_dp,int index)77 static u32 g4x_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
78 {
79 	struct intel_display *display = to_intel_display(intel_dp);
80 
81 	if (index)
82 		return 0;
83 
84 	/*
85 	 * The clock divider is based off the hrawclk, and would like to run at
86 	 * 2MHz.  So, take the hrawclk value and divide by 2000 and use that
87 	 */
88 	return DIV_ROUND_CLOSEST(DISPLAY_RUNTIME_INFO(display)->rawclk_freq, 2000);
89 }
90 
ilk_get_aux_clock_divider(struct intel_dp * intel_dp,int index)91 static u32 ilk_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
92 {
93 	struct intel_display *display = to_intel_display(intel_dp);
94 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
95 	u32 freq;
96 
97 	if (index)
98 		return 0;
99 
100 	/*
101 	 * The clock divider is based off the cdclk or PCH rawclk, and would
102 	 * like to run at 2MHz.  So, take the cdclk or PCH rawclk value and
103 	 * divide by 2000 and use that
104 	 */
105 	if (dig_port->aux_ch == AUX_CH_A)
106 		freq = display->cdclk.hw.cdclk;
107 	else
108 		freq = DISPLAY_RUNTIME_INFO(display)->rawclk_freq;
109 	return DIV_ROUND_CLOSEST(freq, 2000);
110 }
111 
hsw_get_aux_clock_divider(struct intel_dp * intel_dp,int index)112 static u32 hsw_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
113 {
114 	struct intel_display *display = to_intel_display(intel_dp);
115 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
116 
117 	if (dig_port->aux_ch != AUX_CH_A && HAS_PCH_LPT_H(display)) {
118 		/* Workaround for non-ULT HSW */
119 		switch (index) {
120 		case 0: return 63;
121 		case 1: return 72;
122 		default: return 0;
123 		}
124 	}
125 
126 	return ilk_get_aux_clock_divider(intel_dp, index);
127 }
128 
skl_get_aux_clock_divider(struct intel_dp * intel_dp,int index)129 static u32 skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
130 {
131 	/*
132 	 * SKL doesn't need us to program the AUX clock divider (Hardware will
133 	 * derive the clock from CDCLK automatically). We still implement the
134 	 * get_aux_clock_divider vfunc to plug-in into the existing code.
135 	 */
136 	return index ? 0 : 1;
137 }
138 
intel_dp_aux_sync_len(void)139 static int intel_dp_aux_sync_len(void)
140 {
141 	int precharge = 16; /* 10-16 */
142 	int preamble = 16;
143 
144 	return precharge + preamble;
145 }
146 
intel_dp_aux_fw_sync_len(struct intel_dp * intel_dp)147 int intel_dp_aux_fw_sync_len(struct intel_dp *intel_dp)
148 {
149 	int precharge = 10; /* 10-16 */
150 	int preamble = 8;
151 
152 	/*
153 	 * We faced some glitches on Dell Precision 5490 MTL laptop with panel:
154 	 * "Manufacturer: AUO, Model: 63898" when using HW default 18. Using 20
155 	 * is fixing these problems with the panel. It is still within range
156 	 * mentioned in eDP specification. Increasing Fast Wake sync length is
157 	 * causing problems with other panels: increase length as a quirk for
158 	 * this specific laptop.
159 	 */
160 	if (intel_has_dpcd_quirk(intel_dp, QUIRK_FW_SYNC_LEN))
161 		precharge += 2;
162 
163 	return precharge + preamble;
164 }
165 
g4x_dp_aux_precharge_len(void)166 static int g4x_dp_aux_precharge_len(void)
167 {
168 	int precharge_min = 10;
169 	int preamble = 16;
170 
171 	/* HW wants the length of the extra precharge in 2us units */
172 	return (intel_dp_aux_sync_len() -
173 		precharge_min - preamble) / 2;
174 }
175 
g4x_get_aux_send_ctl(struct intel_dp * intel_dp,int send_bytes,u32 aux_clock_divider)176 static u32 g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
177 				int send_bytes,
178 				u32 aux_clock_divider)
179 {
180 	struct intel_display *display = to_intel_display(intel_dp);
181 	u32 timeout;
182 
183 	/* Max timeout value on G4x-BDW: 1.6ms */
184 	if (display->platform.broadwell)
185 		timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
186 	else
187 		timeout = DP_AUX_CH_CTL_TIME_OUT_400us;
188 
189 	return DP_AUX_CH_CTL_SEND_BUSY |
190 		DP_AUX_CH_CTL_DONE |
191 		DP_AUX_CH_CTL_INTERRUPT |
192 		DP_AUX_CH_CTL_TIME_OUT_ERROR |
193 		timeout |
194 		DP_AUX_CH_CTL_RECEIVE_ERROR |
195 		DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
196 		DP_AUX_CH_CTL_PRECHARGE_2US(g4x_dp_aux_precharge_len()) |
197 		DP_AUX_CH_CTL_BIT_CLOCK_2X(aux_clock_divider);
198 }
199 
skl_get_aux_send_ctl(struct intel_dp * intel_dp,int send_bytes,u32 unused)200 static u32 skl_get_aux_send_ctl(struct intel_dp *intel_dp,
201 				int send_bytes,
202 				u32 unused)
203 {
204 	struct intel_display *display = to_intel_display(intel_dp);
205 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
206 	u32 ret;
207 
208 	/*
209 	 * Max timeout values:
210 	 * SKL-GLK: 1.6ms
211 	 * ICL+: 4ms
212 	 */
213 	ret = DP_AUX_CH_CTL_SEND_BUSY |
214 		DP_AUX_CH_CTL_DONE |
215 		DP_AUX_CH_CTL_INTERRUPT |
216 		DP_AUX_CH_CTL_TIME_OUT_ERROR |
217 		DP_AUX_CH_CTL_TIME_OUT_MAX |
218 		DP_AUX_CH_CTL_RECEIVE_ERROR |
219 		DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
220 		DP_AUX_CH_CTL_FW_SYNC_PULSE_SKL(intel_dp_aux_fw_sync_len(intel_dp)) |
221 		DP_AUX_CH_CTL_SYNC_PULSE_SKL(intel_dp_aux_sync_len());
222 
223 	if (intel_tc_port_in_tbt_alt_mode(dig_port))
224 		ret |= DP_AUX_CH_CTL_TBT_IO;
225 
226 	/*
227 	 * Power request bit is already set during aux power well enable.
228 	 * Preserve the bit across aux transactions.
229 	 */
230 	if (DISPLAY_VER(display) >= 14)
231 		ret |= XELPDP_DP_AUX_CH_CTL_POWER_REQUEST;
232 
233 	return ret;
234 }
235 
236 static int
intel_dp_aux_xfer(struct intel_dp * intel_dp,const u8 * send,int send_bytes,u8 * recv,int recv_size,u32 aux_send_ctl_flags)237 intel_dp_aux_xfer(struct intel_dp *intel_dp,
238 		  const u8 *send, int send_bytes,
239 		  u8 *recv, int recv_size,
240 		  u32 aux_send_ctl_flags)
241 {
242 	struct intel_display *display = to_intel_display(intel_dp);
243 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
244 	struct intel_encoder *encoder = &dig_port->base;
245 	i915_reg_t ch_ctl, ch_data[5];
246 	u32 aux_clock_divider;
247 	enum intel_display_power_domain aux_domain;
248 	intel_wakeref_t aux_wakeref;
249 	intel_wakeref_t pps_wakeref = NULL;
250 	int i, ret, recv_bytes;
251 	int try, clock = 0;
252 	u32 status;
253 	bool vdd;
254 
255 	ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
256 	for (i = 0; i < ARRAY_SIZE(ch_data); i++)
257 		ch_data[i] = intel_dp->aux_ch_data_reg(intel_dp, i);
258 
259 	intel_digital_port_lock(encoder);
260 	/*
261 	 * Abort transfers on a disconnected port as required by
262 	 * DP 1.4a link CTS 4.2.1.5, also avoiding the long AUX
263 	 * timeouts that would otherwise happen.
264 	 */
265 	if (!intel_dp_is_edp(intel_dp) &&
266 	    !intel_digital_port_connected_locked(&dig_port->base)) {
267 		ret = -ENXIO;
268 		goto out_unlock;
269 	}
270 
271 	aux_domain = intel_aux_power_domain(dig_port);
272 
273 	aux_wakeref = intel_display_power_get(display, aux_domain);
274 
275 	/*
276 	 * The PPS state needs to be locked for:
277 	 * - eDP on all platforms, since AUX transfers on eDP need VDD power
278 	 *   (either forced or via panel power) which depends on the PPS
279 	 *   state.
280 	 * - non-eDP on platforms where the PPS is a pipe instance (VLV/CHV),
281 	 *   since changing the PPS state (via a parallel modeset for
282 	 *   instance) may interfere with the AUX transfers on a non-eDP
283 	 *   output as well.
284 	 */
285 	if (intel_dp_is_edp(intel_dp) ||
286 	    display->platform.valleyview || display->platform.cherryview)
287 		pps_wakeref = intel_pps_lock(intel_dp);
288 
289 	/*
290 	 * We will be called with VDD already enabled for dpcd/edid/oui reads.
291 	 * In such cases we want to leave VDD enabled and it's up to upper layers
292 	 * to turn it off. But for eg. i2c-dev access we need to turn it on/off
293 	 * ourselves.
294 	 */
295 	vdd = intel_pps_vdd_on_unlocked(intel_dp);
296 
297 	/*
298 	 * dp aux is extremely sensitive to irq latency, hence request the
299 	 * lowest possible wakeup latency and so prevent the cpu from going into
300 	 * deep sleep states.
301 	 */
302 	cpu_latency_qos_update_request(&intel_dp->pm_qos, 0);
303 
304 	intel_pps_check_power_unlocked(intel_dp);
305 
306 	/*
307 	 * FIXME PSR should be disabled here to prevent
308 	 * it using the same AUX CH simultaneously
309 	 */
310 
311 	/* Try to wait for any previous AUX channel activity */
312 	for (try = 0; try < 3; try++) {
313 		status = intel_de_read_notrace(display, ch_ctl);
314 		if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
315 			break;
316 		msleep(1);
317 	}
318 	/* just trace the final value */
319 	trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);
320 
321 	if (try == 3) {
322 		const u32 status = intel_de_read(display, ch_ctl);
323 
324 		if (status != intel_dp->aux_busy_last_status) {
325 			drm_WARN(display->drm, 1,
326 				 "%s: not started (status 0x%08x)\n",
327 				 intel_dp->aux.name, status);
328 			intel_dp->aux_busy_last_status = status;
329 		}
330 
331 		ret = -EBUSY;
332 		goto out;
333 	}
334 
335 	/* Only 5 data registers! */
336 	if (drm_WARN_ON(display->drm, send_bytes > 20 || recv_size > 20)) {
337 		ret = -E2BIG;
338 		goto out;
339 	}
340 
341 	while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
342 		u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
343 							  send_bytes,
344 							  aux_clock_divider);
345 
346 		send_ctl |= aux_send_ctl_flags;
347 
348 		/* Must try at least 3 times according to DP spec */
349 		for (try = 0; try < 5; try++) {
350 			/* Load the send data into the aux channel data registers */
351 			for (i = 0; i < send_bytes; i += 4)
352 				intel_de_write(display, ch_data[i >> 2],
353 					       intel_dp_aux_pack(send + i,
354 								 send_bytes - i));
355 
356 			/* Send the command and wait for it to complete */
357 			intel_de_write(display, ch_ctl, send_ctl);
358 
359 			status = intel_dp_aux_wait_done(intel_dp);
360 
361 			/* Clear done status and any errors */
362 			intel_de_write(display, ch_ctl,
363 				       status | DP_AUX_CH_CTL_DONE |
364 				       DP_AUX_CH_CTL_TIME_OUT_ERROR |
365 				       DP_AUX_CH_CTL_RECEIVE_ERROR);
366 
367 			/*
368 			 * DP CTS 1.2 Core Rev 1.1, 4.2.1.1 & 4.2.1.2
369 			 *   400us delay required for errors and timeouts
370 			 *   Timeout errors from the HW already meet this
371 			 *   requirement so skip to next iteration
372 			 */
373 			if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR)
374 				continue;
375 
376 			if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
377 				usleep_range(400, 500);
378 				continue;
379 			}
380 			if (status & DP_AUX_CH_CTL_DONE)
381 				goto done;
382 		}
383 	}
384 
385 	if ((status & DP_AUX_CH_CTL_DONE) == 0) {
386 		drm_err(display->drm, "%s: not done (status 0x%08x)\n",
387 			intel_dp->aux.name, status);
388 		ret = -EBUSY;
389 		goto out;
390 	}
391 
392 done:
393 	/*
394 	 * Check for timeout or receive error. Timeouts occur when the sink is
395 	 * not connected.
396 	 */
397 	if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
398 		drm_err(display->drm, "%s: receive error (status 0x%08x)\n",
399 			intel_dp->aux.name, status);
400 		ret = -EIO;
401 		goto out;
402 	}
403 
404 	/*
405 	 * Timeouts occur when the device isn't connected, so they're "normal"
406 	 * -- don't fill the kernel log with these
407 	 */
408 	if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
409 		drm_dbg_kms(display->drm, "%s: timeout (status 0x%08x)\n",
410 			    intel_dp->aux.name, status);
411 		ret = -ETIMEDOUT;
412 		goto out;
413 	}
414 
415 	/* Unload any bytes sent back from the other side */
416 	recv_bytes = REG_FIELD_GET(DP_AUX_CH_CTL_MESSAGE_SIZE_MASK, status);
417 
418 	/*
419 	 * By BSpec: "Message sizes of 0 or >20 are not allowed."
420 	 * We have no idea of what happened so we return -EBUSY so
421 	 * drm layer takes care for the necessary retries.
422 	 */
423 	if (recv_bytes == 0 || recv_bytes > 20) {
424 		drm_dbg_kms(display->drm,
425 			    "%s: Forbidden recv_bytes = %d on aux transaction\n",
426 			    intel_dp->aux.name, recv_bytes);
427 		ret = -EBUSY;
428 		goto out;
429 	}
430 
431 	if (recv_bytes > recv_size)
432 		recv_bytes = recv_size;
433 
434 	for (i = 0; i < recv_bytes; i += 4)
435 		intel_dp_aux_unpack(intel_de_read(display, ch_data[i >> 2]),
436 				    recv + i, recv_bytes - i);
437 
438 	ret = recv_bytes;
439 out:
440 	cpu_latency_qos_update_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
441 
442 	if (vdd)
443 		intel_pps_vdd_off_unlocked(intel_dp, false);
444 
445 	if (pps_wakeref)
446 		intel_pps_unlock(intel_dp, pps_wakeref);
447 
448 	intel_display_power_put_async(display, aux_domain, aux_wakeref);
449 out_unlock:
450 	intel_digital_port_unlock(encoder);
451 
452 	return ret;
453 }
454 
455 #define BARE_ADDRESS_SIZE	3
456 #define HEADER_SIZE		(BARE_ADDRESS_SIZE + 1)
457 
458 static void
intel_dp_aux_header(u8 txbuf[HEADER_SIZE],const struct drm_dp_aux_msg * msg)459 intel_dp_aux_header(u8 txbuf[HEADER_SIZE],
460 		    const struct drm_dp_aux_msg *msg)
461 {
462 	txbuf[0] = (msg->request << 4) | ((msg->address >> 16) & 0xf);
463 	txbuf[1] = (msg->address >> 8) & 0xff;
464 	txbuf[2] = msg->address & 0xff;
465 	txbuf[3] = msg->size - 1;
466 }
467 
intel_dp_aux_xfer_flags(const struct drm_dp_aux_msg * msg)468 static u32 intel_dp_aux_xfer_flags(const struct drm_dp_aux_msg *msg)
469 {
470 	/*
471 	 * If we're trying to send the HDCP Aksv, we need to set a the Aksv
472 	 * select bit to inform the hardware to send the Aksv after our header
473 	 * since we can't access that data from software.
474 	 */
475 	if ((msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_NATIVE_WRITE &&
476 	    msg->address == DP_AUX_HDCP_AKSV)
477 		return DP_AUX_CH_CTL_AUX_AKSV_SELECT;
478 
479 	return 0;
480 }
481 
482 static ssize_t
intel_dp_aux_transfer(struct drm_dp_aux * aux,struct drm_dp_aux_msg * msg)483 intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
484 {
485 	struct intel_dp *intel_dp = container_of(aux, struct intel_dp, aux);
486 	struct intel_display *display = to_intel_display(intel_dp);
487 	u8 txbuf[20], rxbuf[20];
488 	size_t txsize, rxsize;
489 	u32 flags = intel_dp_aux_xfer_flags(msg);
490 	int ret;
491 
492 	intel_dp_aux_header(txbuf, msg);
493 
494 	switch (msg->request & ~DP_AUX_I2C_MOT) {
495 	case DP_AUX_NATIVE_WRITE:
496 	case DP_AUX_I2C_WRITE:
497 	case DP_AUX_I2C_WRITE_STATUS_UPDATE:
498 		txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
499 		rxsize = 2; /* 0 or 1 data bytes */
500 
501 		if (drm_WARN_ON(display->drm, txsize > 20))
502 			return -E2BIG;
503 
504 		drm_WARN_ON(display->drm, !msg->buffer != !msg->size);
505 
506 		if (msg->buffer)
507 			memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);
508 
509 		ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
510 					rxbuf, rxsize, flags);
511 		if (ret > 0) {
512 			msg->reply = rxbuf[0] >> 4;
513 
514 			if (ret > 1) {
515 				/* Number of bytes written in a short write. */
516 				ret = clamp_t(int, rxbuf[1], 0, msg->size);
517 			} else {
518 				/* Return payload size. */
519 				ret = msg->size;
520 			}
521 		}
522 		break;
523 
524 	case DP_AUX_NATIVE_READ:
525 	case DP_AUX_I2C_READ:
526 		txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
527 		rxsize = msg->size + 1;
528 
529 		if (drm_WARN_ON(display->drm, rxsize > 20))
530 			return -E2BIG;
531 
532 		ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
533 					rxbuf, rxsize, flags);
534 		if (ret > 0) {
535 			msg->reply = rxbuf[0] >> 4;
536 			/*
537 			 * Assume happy day, and copy the data. The caller is
538 			 * expected to check msg->reply before touching it.
539 			 *
540 			 * Return payload size.
541 			 */
542 			ret--;
543 			memcpy(msg->buffer, rxbuf + 1, ret);
544 		}
545 		break;
546 
547 	default:
548 		ret = -EINVAL;
549 		break;
550 	}
551 
552 	return ret;
553 }
554 
vlv_aux_ctl_reg(struct intel_dp * intel_dp)555 static i915_reg_t vlv_aux_ctl_reg(struct intel_dp *intel_dp)
556 {
557 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
558 	enum aux_ch aux_ch = dig_port->aux_ch;
559 
560 	switch (aux_ch) {
561 	case AUX_CH_B:
562 	case AUX_CH_C:
563 	case AUX_CH_D:
564 		return VLV_DP_AUX_CH_CTL(aux_ch);
565 	default:
566 		MISSING_CASE(aux_ch);
567 		return VLV_DP_AUX_CH_CTL(AUX_CH_B);
568 	}
569 }
570 
vlv_aux_data_reg(struct intel_dp * intel_dp,int index)571 static i915_reg_t vlv_aux_data_reg(struct intel_dp *intel_dp, int index)
572 {
573 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
574 	enum aux_ch aux_ch = dig_port->aux_ch;
575 
576 	switch (aux_ch) {
577 	case AUX_CH_B:
578 	case AUX_CH_C:
579 	case AUX_CH_D:
580 		return VLV_DP_AUX_CH_DATA(aux_ch, index);
581 	default:
582 		MISSING_CASE(aux_ch);
583 		return VLV_DP_AUX_CH_DATA(AUX_CH_B, index);
584 	}
585 }
586 
g4x_aux_ctl_reg(struct intel_dp * intel_dp)587 static i915_reg_t g4x_aux_ctl_reg(struct intel_dp *intel_dp)
588 {
589 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
590 	enum aux_ch aux_ch = dig_port->aux_ch;
591 
592 	switch (aux_ch) {
593 	case AUX_CH_B:
594 	case AUX_CH_C:
595 	case AUX_CH_D:
596 		return DP_AUX_CH_CTL(aux_ch);
597 	default:
598 		MISSING_CASE(aux_ch);
599 		return DP_AUX_CH_CTL(AUX_CH_B);
600 	}
601 }
602 
g4x_aux_data_reg(struct intel_dp * intel_dp,int index)603 static i915_reg_t g4x_aux_data_reg(struct intel_dp *intel_dp, int index)
604 {
605 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
606 	enum aux_ch aux_ch = dig_port->aux_ch;
607 
608 	switch (aux_ch) {
609 	case AUX_CH_B:
610 	case AUX_CH_C:
611 	case AUX_CH_D:
612 		return DP_AUX_CH_DATA(aux_ch, index);
613 	default:
614 		MISSING_CASE(aux_ch);
615 		return DP_AUX_CH_DATA(AUX_CH_B, index);
616 	}
617 }
618 
ilk_aux_ctl_reg(struct intel_dp * intel_dp)619 static i915_reg_t ilk_aux_ctl_reg(struct intel_dp *intel_dp)
620 {
621 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
622 	enum aux_ch aux_ch = dig_port->aux_ch;
623 
624 	switch (aux_ch) {
625 	case AUX_CH_A:
626 		return DP_AUX_CH_CTL(aux_ch);
627 	case AUX_CH_B:
628 	case AUX_CH_C:
629 	case AUX_CH_D:
630 		return PCH_DP_AUX_CH_CTL(aux_ch);
631 	default:
632 		MISSING_CASE(aux_ch);
633 		return DP_AUX_CH_CTL(AUX_CH_A);
634 	}
635 }
636 
ilk_aux_data_reg(struct intel_dp * intel_dp,int index)637 static i915_reg_t ilk_aux_data_reg(struct intel_dp *intel_dp, int index)
638 {
639 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
640 	enum aux_ch aux_ch = dig_port->aux_ch;
641 
642 	switch (aux_ch) {
643 	case AUX_CH_A:
644 		return DP_AUX_CH_DATA(aux_ch, index);
645 	case AUX_CH_B:
646 	case AUX_CH_C:
647 	case AUX_CH_D:
648 		return PCH_DP_AUX_CH_DATA(aux_ch, index);
649 	default:
650 		MISSING_CASE(aux_ch);
651 		return DP_AUX_CH_DATA(AUX_CH_A, index);
652 	}
653 }
654 
skl_aux_ctl_reg(struct intel_dp * intel_dp)655 static i915_reg_t skl_aux_ctl_reg(struct intel_dp *intel_dp)
656 {
657 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
658 	enum aux_ch aux_ch = dig_port->aux_ch;
659 
660 	switch (aux_ch) {
661 	case AUX_CH_A:
662 	case AUX_CH_B:
663 	case AUX_CH_C:
664 	case AUX_CH_D:
665 	case AUX_CH_E:
666 	case AUX_CH_F:
667 		return DP_AUX_CH_CTL(aux_ch);
668 	default:
669 		MISSING_CASE(aux_ch);
670 		return DP_AUX_CH_CTL(AUX_CH_A);
671 	}
672 }
673 
skl_aux_data_reg(struct intel_dp * intel_dp,int index)674 static i915_reg_t skl_aux_data_reg(struct intel_dp *intel_dp, int index)
675 {
676 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
677 	enum aux_ch aux_ch = dig_port->aux_ch;
678 
679 	switch (aux_ch) {
680 	case AUX_CH_A:
681 	case AUX_CH_B:
682 	case AUX_CH_C:
683 	case AUX_CH_D:
684 	case AUX_CH_E:
685 	case AUX_CH_F:
686 		return DP_AUX_CH_DATA(aux_ch, index);
687 	default:
688 		MISSING_CASE(aux_ch);
689 		return DP_AUX_CH_DATA(AUX_CH_A, index);
690 	}
691 }
692 
tgl_aux_ctl_reg(struct intel_dp * intel_dp)693 static i915_reg_t tgl_aux_ctl_reg(struct intel_dp *intel_dp)
694 {
695 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
696 	enum aux_ch aux_ch = dig_port->aux_ch;
697 
698 	switch (aux_ch) {
699 	case AUX_CH_A:
700 	case AUX_CH_B:
701 	case AUX_CH_C:
702 	case AUX_CH_USBC1:
703 	case AUX_CH_USBC2:
704 	case AUX_CH_USBC3:
705 	case AUX_CH_USBC4:
706 	case AUX_CH_USBC5:  /* aka AUX_CH_D_XELPD */
707 	case AUX_CH_USBC6:  /* aka AUX_CH_E_XELPD */
708 		return DP_AUX_CH_CTL(aux_ch);
709 	default:
710 		MISSING_CASE(aux_ch);
711 		return DP_AUX_CH_CTL(AUX_CH_A);
712 	}
713 }
714 
tgl_aux_data_reg(struct intel_dp * intel_dp,int index)715 static i915_reg_t tgl_aux_data_reg(struct intel_dp *intel_dp, int index)
716 {
717 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
718 	enum aux_ch aux_ch = dig_port->aux_ch;
719 
720 	switch (aux_ch) {
721 	case AUX_CH_A:
722 	case AUX_CH_B:
723 	case AUX_CH_C:
724 	case AUX_CH_USBC1:
725 	case AUX_CH_USBC2:
726 	case AUX_CH_USBC3:
727 	case AUX_CH_USBC4:
728 	case AUX_CH_USBC5:  /* aka AUX_CH_D_XELPD */
729 	case AUX_CH_USBC6:  /* aka AUX_CH_E_XELPD */
730 		return DP_AUX_CH_DATA(aux_ch, index);
731 	default:
732 		MISSING_CASE(aux_ch);
733 		return DP_AUX_CH_DATA(AUX_CH_A, index);
734 	}
735 }
736 
xelpdp_aux_ctl_reg(struct intel_dp * intel_dp)737 static i915_reg_t xelpdp_aux_ctl_reg(struct intel_dp *intel_dp)
738 {
739 	struct intel_display *display = to_intel_display(intel_dp);
740 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
741 	enum aux_ch aux_ch = dig_port->aux_ch;
742 
743 	switch (aux_ch) {
744 	case AUX_CH_A:
745 	case AUX_CH_B:
746 	case AUX_CH_USBC1:
747 	case AUX_CH_USBC2:
748 	case AUX_CH_USBC3:
749 	case AUX_CH_USBC4:
750 		return XELPDP_DP_AUX_CH_CTL(display, aux_ch);
751 	default:
752 		MISSING_CASE(aux_ch);
753 		return XELPDP_DP_AUX_CH_CTL(display, AUX_CH_A);
754 	}
755 }
756 
xelpdp_aux_data_reg(struct intel_dp * intel_dp,int index)757 static i915_reg_t xelpdp_aux_data_reg(struct intel_dp *intel_dp, int index)
758 {
759 	struct intel_display *display = to_intel_display(intel_dp);
760 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
761 	enum aux_ch aux_ch = dig_port->aux_ch;
762 
763 	switch (aux_ch) {
764 	case AUX_CH_A:
765 	case AUX_CH_B:
766 	case AUX_CH_USBC1:
767 	case AUX_CH_USBC2:
768 	case AUX_CH_USBC3:
769 	case AUX_CH_USBC4:
770 		return XELPDP_DP_AUX_CH_DATA(display, aux_ch, index);
771 	default:
772 		MISSING_CASE(aux_ch);
773 		return XELPDP_DP_AUX_CH_DATA(display, AUX_CH_A, index);
774 	}
775 }
776 
intel_dp_aux_fini(struct intel_dp * intel_dp)777 void intel_dp_aux_fini(struct intel_dp *intel_dp)
778 {
779 	if (cpu_latency_qos_request_active(&intel_dp->pm_qos))
780 		cpu_latency_qos_remove_request(&intel_dp->pm_qos);
781 
782 	kfree(intel_dp->aux.name);
783 }
784 
intel_dp_aux_init(struct intel_dp * intel_dp)785 void intel_dp_aux_init(struct intel_dp *intel_dp)
786 {
787 	struct intel_display *display = to_intel_display(intel_dp);
788 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
789 	struct intel_encoder *encoder = &dig_port->base;
790 	enum aux_ch aux_ch = dig_port->aux_ch;
791 	char buf[AUX_CH_NAME_BUFSIZE];
792 
793 	if (DISPLAY_VER(display) >= 14) {
794 		intel_dp->aux_ch_ctl_reg = xelpdp_aux_ctl_reg;
795 		intel_dp->aux_ch_data_reg = xelpdp_aux_data_reg;
796 	} else if (DISPLAY_VER(display) >= 12) {
797 		intel_dp->aux_ch_ctl_reg = tgl_aux_ctl_reg;
798 		intel_dp->aux_ch_data_reg = tgl_aux_data_reg;
799 	} else if (DISPLAY_VER(display) >= 9) {
800 		intel_dp->aux_ch_ctl_reg = skl_aux_ctl_reg;
801 		intel_dp->aux_ch_data_reg = skl_aux_data_reg;
802 	} else if (HAS_PCH_SPLIT(display)) {
803 		intel_dp->aux_ch_ctl_reg = ilk_aux_ctl_reg;
804 		intel_dp->aux_ch_data_reg = ilk_aux_data_reg;
805 	} else if (display->platform.valleyview || display->platform.cherryview) {
806 		intel_dp->aux_ch_ctl_reg = vlv_aux_ctl_reg;
807 		intel_dp->aux_ch_data_reg = vlv_aux_data_reg;
808 	} else {
809 		intel_dp->aux_ch_ctl_reg = g4x_aux_ctl_reg;
810 		intel_dp->aux_ch_data_reg = g4x_aux_data_reg;
811 	}
812 
813 	if (DISPLAY_VER(display) >= 9)
814 		intel_dp->get_aux_clock_divider = skl_get_aux_clock_divider;
815 	else if (display->platform.broadwell || display->platform.haswell)
816 		intel_dp->get_aux_clock_divider = hsw_get_aux_clock_divider;
817 	else if (HAS_PCH_SPLIT(display))
818 		intel_dp->get_aux_clock_divider = ilk_get_aux_clock_divider;
819 	else
820 		intel_dp->get_aux_clock_divider = g4x_get_aux_clock_divider;
821 
822 	if (DISPLAY_VER(display) >= 9)
823 		intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
824 	else
825 		intel_dp->get_aux_send_ctl = g4x_get_aux_send_ctl;
826 
827 	intel_dp->aux.drm_dev = display->drm;
828 	drm_dp_aux_init(&intel_dp->aux);
829 
830 	/* Failure to allocate our preferred name is not critical */
831 	intel_dp->aux.name = kasprintf(GFP_KERNEL, "AUX %s/%s",
832 				       aux_ch_name(display, buf, sizeof(buf), aux_ch),
833 				       encoder->base.name);
834 
835 	intel_dp->aux.transfer = intel_dp_aux_transfer;
836 	cpu_latency_qos_add_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
837 
838 	intel_dp_dpcd_set_probe(intel_dp, true);
839 }
840 
default_aux_ch(struct intel_encoder * encoder)841 static enum aux_ch default_aux_ch(struct intel_encoder *encoder)
842 {
843 	struct intel_display *display = to_intel_display(encoder);
844 
845 	/* SKL has DDI E but no AUX E */
846 	if (DISPLAY_VER(display) == 9 && encoder->port == PORT_E)
847 		return AUX_CH_A;
848 
849 	return (enum aux_ch)encoder->port;
850 }
851 
852 static struct intel_encoder *
get_encoder_by_aux_ch(struct intel_encoder * encoder,enum aux_ch aux_ch)853 get_encoder_by_aux_ch(struct intel_encoder *encoder,
854 		      enum aux_ch aux_ch)
855 {
856 	struct intel_display *display = to_intel_display(encoder);
857 	struct intel_encoder *other;
858 
859 	for_each_intel_encoder(display->drm, other) {
860 		if (other == encoder)
861 			continue;
862 
863 		if (!intel_encoder_is_dig_port(other))
864 			continue;
865 
866 		if (enc_to_dig_port(other)->aux_ch == aux_ch)
867 			return other;
868 	}
869 
870 	return NULL;
871 }
872 
intel_dp_aux_ch(struct intel_encoder * encoder)873 enum aux_ch intel_dp_aux_ch(struct intel_encoder *encoder)
874 {
875 	struct intel_display *display = to_intel_display(encoder);
876 	struct intel_encoder *other;
877 	const char *source;
878 	enum aux_ch aux_ch;
879 	char buf[AUX_CH_NAME_BUFSIZE];
880 
881 	aux_ch = intel_bios_dp_aux_ch(encoder->devdata);
882 	source = "VBT";
883 
884 	if (aux_ch == AUX_CH_NONE) {
885 		aux_ch = default_aux_ch(encoder);
886 		source = "platform default";
887 	}
888 
889 	if (aux_ch == AUX_CH_NONE)
890 		return AUX_CH_NONE;
891 
892 	/* FIXME validate aux_ch against platform caps */
893 
894 	other = get_encoder_by_aux_ch(encoder, aux_ch);
895 	if (other) {
896 		drm_dbg_kms(display->drm,
897 			    "[ENCODER:%d:%s] AUX CH %s already claimed by [ENCODER:%d:%s]\n",
898 			    encoder->base.base.id, encoder->base.name,
899 			    aux_ch_name(display, buf, sizeof(buf), aux_ch),
900 			    other->base.base.id, other->base.name);
901 		return AUX_CH_NONE;
902 	}
903 
904 	drm_dbg_kms(display->drm,
905 		    "[ENCODER:%d:%s] Using AUX CH %s (%s)\n",
906 		    encoder->base.base.id, encoder->base.name,
907 		    aux_ch_name(display, buf, sizeof(buf), aux_ch), source);
908 
909 	return aux_ch;
910 }
911 
intel_dp_aux_irq_handler(struct intel_display * display)912 void intel_dp_aux_irq_handler(struct intel_display *display)
913 {
914 	wake_up_all(&display->gmbus.wait_queue);
915 }
916