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v6.13.7
  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_quirks.h"
 17#include "intel_tc.h"
 18
 19#define AUX_CH_NAME_BUFSIZE	6
 20
 21static 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
 34u32 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
 46static 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
 56static u32
 57intel_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
 77static 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
 91static 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
112static 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 drm_i915_private *i915 = to_i915(display->drm);
116	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
117
118	if (dig_port->aux_ch != AUX_CH_A && HAS_PCH_LPT_H(i915)) {
119		/* Workaround for non-ULT HSW */
120		switch (index) {
121		case 0: return 63;
122		case 1: return 72;
123		default: return 0;
124		}
125	}
126
127	return ilk_get_aux_clock_divider(intel_dp, index);
128}
129
130static u32 skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
131{
132	/*
133	 * SKL doesn't need us to program the AUX clock divider (Hardware will
134	 * derive the clock from CDCLK automatically). We still implement the
135	 * get_aux_clock_divider vfunc to plug-in into the existing code.
136	 */
137	return index ? 0 : 1;
138}
139
140static int intel_dp_aux_sync_len(void)
141{
142	int precharge = 16; /* 10-16 */
143	int preamble = 16;
144
145	return precharge + preamble;
146}
147
148int intel_dp_aux_fw_sync_len(struct intel_dp *intel_dp)
149{
150	int precharge = 10; /* 10-16 */
151	int preamble = 8;
152
153	/*
154	 * We faced some glitches on Dell Precision 5490 MTL laptop with panel:
155	 * "Manufacturer: AUO, Model: 63898" when using HW default 18. Using 20
156	 * is fixing these problems with the panel. It is still within range
157	 * mentioned in eDP specification. Increasing Fast Wake sync length is
158	 * causing problems with other panels: increase length as a quirk for
159	 * this specific laptop.
160	 */
161	if (intel_has_dpcd_quirk(intel_dp, QUIRK_FW_SYNC_LEN))
162		precharge += 2;
163
164	return precharge + preamble;
165}
166
167static int g4x_dp_aux_precharge_len(void)
168{
169	int precharge_min = 10;
170	int preamble = 16;
171
172	/* HW wants the length of the extra precharge in 2us units */
173	return (intel_dp_aux_sync_len() -
174		precharge_min - preamble) / 2;
175}
176
177static u32 g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
178				int send_bytes,
179				u32 aux_clock_divider)
180{
181	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
182	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
183	u32 timeout;
184
185	/* Max timeout value on G4x-BDW: 1.6ms */
186	if (IS_BROADWELL(i915))
187		timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
188	else
189		timeout = DP_AUX_CH_CTL_TIME_OUT_400us;
190
191	return DP_AUX_CH_CTL_SEND_BUSY |
192		DP_AUX_CH_CTL_DONE |
193		DP_AUX_CH_CTL_INTERRUPT |
194		DP_AUX_CH_CTL_TIME_OUT_ERROR |
195		timeout |
196		DP_AUX_CH_CTL_RECEIVE_ERROR |
197		DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
198		DP_AUX_CH_CTL_PRECHARGE_2US(g4x_dp_aux_precharge_len()) |
199		DP_AUX_CH_CTL_BIT_CLOCK_2X(aux_clock_divider);
200}
201
202static u32 skl_get_aux_send_ctl(struct intel_dp *intel_dp,
203				int send_bytes,
204				u32 unused)
205{
206	struct intel_display *display = to_intel_display(intel_dp);
207	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 
208	u32 ret;
209
210	/*
211	 * Max timeout values:
212	 * SKL-GLK: 1.6ms
213	 * ICL+: 4ms
214	 */
215	ret = DP_AUX_CH_CTL_SEND_BUSY |
216		DP_AUX_CH_CTL_DONE |
217		DP_AUX_CH_CTL_INTERRUPT |
218		DP_AUX_CH_CTL_TIME_OUT_ERROR |
219		DP_AUX_CH_CTL_TIME_OUT_MAX |
220		DP_AUX_CH_CTL_RECEIVE_ERROR |
221		DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
222		DP_AUX_CH_CTL_FW_SYNC_PULSE_SKL(intel_dp_aux_fw_sync_len(intel_dp)) |
223		DP_AUX_CH_CTL_SYNC_PULSE_SKL(intel_dp_aux_sync_len());
224
225	if (intel_tc_port_in_tbt_alt_mode(dig_port))
226		ret |= DP_AUX_CH_CTL_TBT_IO;
227
228	/*
229	 * Power request bit is already set during aux power well enable.
230	 * Preserve the bit across aux transactions.
231	 */
232	if (DISPLAY_VER(display) >= 14)
233		ret |= XELPDP_DP_AUX_CH_CTL_POWER_REQUEST;
234
235	return ret;
236}
237
238static int
239intel_dp_aux_xfer(struct intel_dp *intel_dp,
240		  const u8 *send, int send_bytes,
241		  u8 *recv, int recv_size,
242		  u32 aux_send_ctl_flags)
243{
244	struct intel_display *display = to_intel_display(intel_dp);
245	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
246	struct intel_encoder *encoder = &dig_port->base;
247	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
 
 
248	i915_reg_t ch_ctl, ch_data[5];
249	u32 aux_clock_divider;
250	enum intel_display_power_domain aux_domain;
251	intel_wakeref_t aux_wakeref;
252	intel_wakeref_t pps_wakeref;
253	int i, ret, recv_bytes;
254	int try, clock = 0;
255	u32 status;
256	bool vdd;
257
258	ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
259	for (i = 0; i < ARRAY_SIZE(ch_data); i++)
260		ch_data[i] = intel_dp->aux_ch_data_reg(intel_dp, i);
261
262	intel_digital_port_lock(encoder);
263	/*
264	 * Abort transfers on a disconnected port as required by
265	 * DP 1.4a link CTS 4.2.1.5, also avoiding the long AUX
266	 * timeouts that would otherwise happen.
267	 */
268	if (!intel_dp_is_edp(intel_dp) &&
269	    !intel_digital_port_connected_locked(&dig_port->base)) {
270		ret = -ENXIO;
271		goto out_unlock;
 
 
272	}
273
274	aux_domain = intel_aux_power_domain(dig_port);
275
276	aux_wakeref = intel_display_power_get(i915, aux_domain);
277	pps_wakeref = intel_pps_lock(intel_dp);
278
279	/*
280	 * We will be called with VDD already enabled for dpcd/edid/oui reads.
281	 * In such cases we want to leave VDD enabled and it's up to upper layers
282	 * to turn it off. But for eg. i2c-dev access we need to turn it on/off
283	 * ourselves.
284	 */
285	vdd = intel_pps_vdd_on_unlocked(intel_dp);
286
287	/*
288	 * dp aux is extremely sensitive to irq latency, hence request the
289	 * lowest possible wakeup latency and so prevent the cpu from going into
290	 * deep sleep states.
291	 */
292	cpu_latency_qos_update_request(&intel_dp->pm_qos, 0);
293
294	intel_pps_check_power_unlocked(intel_dp);
295
296	/*
297	 * FIXME PSR should be disabled here to prevent
298	 * it using the same AUX CH simultaneously
299	 */
300
301	/* Try to wait for any previous AUX channel activity */
302	for (try = 0; try < 3; try++) {
303		status = intel_de_read_notrace(display, ch_ctl);
304		if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
305			break;
306		msleep(1);
307	}
308	/* just trace the final value */
309	trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);
310
311	if (try == 3) {
312		const u32 status = intel_de_read(display, ch_ctl);
313
314		if (status != intel_dp->aux_busy_last_status) {
315			drm_WARN(display->drm, 1,
316				 "%s: not started (status 0x%08x)\n",
317				 intel_dp->aux.name, status);
318			intel_dp->aux_busy_last_status = status;
319		}
320
321		ret = -EBUSY;
322		goto out;
323	}
324
325	/* Only 5 data registers! */
326	if (drm_WARN_ON(display->drm, send_bytes > 20 || recv_size > 20)) {
327		ret = -E2BIG;
328		goto out;
329	}
330
331	while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
332		u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
333							  send_bytes,
334							  aux_clock_divider);
335
336		send_ctl |= aux_send_ctl_flags;
337
338		/* Must try at least 3 times according to DP spec */
339		for (try = 0; try < 5; try++) {
340			/* Load the send data into the aux channel data registers */
341			for (i = 0; i < send_bytes; i += 4)
342				intel_de_write(display, ch_data[i >> 2],
343					       intel_dp_aux_pack(send + i,
344								 send_bytes - i));
345
346			/* Send the command and wait for it to complete */
347			intel_de_write(display, ch_ctl, send_ctl);
348
349			status = intel_dp_aux_wait_done(intel_dp);
350
351			/* Clear done status and any errors */
352			intel_de_write(display, ch_ctl,
353				       status | DP_AUX_CH_CTL_DONE |
354				       DP_AUX_CH_CTL_TIME_OUT_ERROR |
355				       DP_AUX_CH_CTL_RECEIVE_ERROR);
356
357			/*
358			 * DP CTS 1.2 Core Rev 1.1, 4.2.1.1 & 4.2.1.2
359			 *   400us delay required for errors and timeouts
360			 *   Timeout errors from the HW already meet this
361			 *   requirement so skip to next iteration
362			 */
363			if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR)
364				continue;
365
366			if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
367				usleep_range(400, 500);
368				continue;
369			}
370			if (status & DP_AUX_CH_CTL_DONE)
371				goto done;
372		}
373	}
374
375	if ((status & DP_AUX_CH_CTL_DONE) == 0) {
376		drm_err(display->drm, "%s: not done (status 0x%08x)\n",
377			intel_dp->aux.name, status);
378		ret = -EBUSY;
379		goto out;
380	}
381
382done:
383	/*
384	 * Check for timeout or receive error. Timeouts occur when the sink is
385	 * not connected.
386	 */
387	if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
388		drm_err(display->drm, "%s: receive error (status 0x%08x)\n",
389			intel_dp->aux.name, status);
390		ret = -EIO;
391		goto out;
392	}
393
394	/*
395	 * Timeouts occur when the device isn't connected, so they're "normal"
396	 * -- don't fill the kernel log with these
397	 */
398	if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
399		drm_dbg_kms(display->drm, "%s: timeout (status 0x%08x)\n",
400			    intel_dp->aux.name, status);
401		ret = -ETIMEDOUT;
402		goto out;
403	}
404
405	/* Unload any bytes sent back from the other side */
406	recv_bytes = REG_FIELD_GET(DP_AUX_CH_CTL_MESSAGE_SIZE_MASK, status);
407
408	/*
409	 * By BSpec: "Message sizes of 0 or >20 are not allowed."
410	 * We have no idea of what happened so we return -EBUSY so
411	 * drm layer takes care for the necessary retries.
412	 */
413	if (recv_bytes == 0 || recv_bytes > 20) {
414		drm_dbg_kms(display->drm,
415			    "%s: Forbidden recv_bytes = %d on aux transaction\n",
416			    intel_dp->aux.name, recv_bytes);
417		ret = -EBUSY;
418		goto out;
419	}
420
421	if (recv_bytes > recv_size)
422		recv_bytes = recv_size;
423
424	for (i = 0; i < recv_bytes; i += 4)
425		intel_dp_aux_unpack(intel_de_read(display, ch_data[i >> 2]),
426				    recv + i, recv_bytes - i);
427
428	ret = recv_bytes;
429out:
430	cpu_latency_qos_update_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
431
432	if (vdd)
433		intel_pps_vdd_off_unlocked(intel_dp, false);
434
435	intel_pps_unlock(intel_dp, pps_wakeref);
436	intel_display_power_put_async(i915, aux_domain, aux_wakeref);
437out_unlock:
438	intel_digital_port_unlock(encoder);
 
439
440	return ret;
441}
442
443#define BARE_ADDRESS_SIZE	3
444#define HEADER_SIZE		(BARE_ADDRESS_SIZE + 1)
445
446static void
447intel_dp_aux_header(u8 txbuf[HEADER_SIZE],
448		    const struct drm_dp_aux_msg *msg)
449{
450	txbuf[0] = (msg->request << 4) | ((msg->address >> 16) & 0xf);
451	txbuf[1] = (msg->address >> 8) & 0xff;
452	txbuf[2] = msg->address & 0xff;
453	txbuf[3] = msg->size - 1;
454}
455
456static u32 intel_dp_aux_xfer_flags(const struct drm_dp_aux_msg *msg)
457{
458	/*
459	 * If we're trying to send the HDCP Aksv, we need to set a the Aksv
460	 * select bit to inform the hardware to send the Aksv after our header
461	 * since we can't access that data from software.
462	 */
463	if ((msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_NATIVE_WRITE &&
464	    msg->address == DP_AUX_HDCP_AKSV)
465		return DP_AUX_CH_CTL_AUX_AKSV_SELECT;
466
467	return 0;
468}
469
470static ssize_t
471intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
472{
473	struct intel_dp *intel_dp = container_of(aux, struct intel_dp, aux);
474	struct intel_display *display = to_intel_display(intel_dp);
475	u8 txbuf[20], rxbuf[20];
476	size_t txsize, rxsize;
477	u32 flags = intel_dp_aux_xfer_flags(msg);
478	int ret;
479
480	intel_dp_aux_header(txbuf, msg);
481
482	switch (msg->request & ~DP_AUX_I2C_MOT) {
483	case DP_AUX_NATIVE_WRITE:
484	case DP_AUX_I2C_WRITE:
485	case DP_AUX_I2C_WRITE_STATUS_UPDATE:
486		txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
487		rxsize = 2; /* 0 or 1 data bytes */
488
489		if (drm_WARN_ON(display->drm, txsize > 20))
490			return -E2BIG;
491
492		drm_WARN_ON(display->drm, !msg->buffer != !msg->size);
493
494		if (msg->buffer)
495			memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);
496
497		ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
498					rxbuf, rxsize, flags);
499		if (ret > 0) {
500			msg->reply = rxbuf[0] >> 4;
501
502			if (ret > 1) {
503				/* Number of bytes written in a short write. */
504				ret = clamp_t(int, rxbuf[1], 0, msg->size);
505			} else {
506				/* Return payload size. */
507				ret = msg->size;
508			}
509		}
510		break;
511
512	case DP_AUX_NATIVE_READ:
513	case DP_AUX_I2C_READ:
514		txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
515		rxsize = msg->size + 1;
516
517		if (drm_WARN_ON(display->drm, rxsize > 20))
518			return -E2BIG;
519
520		ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
521					rxbuf, rxsize, flags);
522		if (ret > 0) {
523			msg->reply = rxbuf[0] >> 4;
524			/*
525			 * Assume happy day, and copy the data. The caller is
526			 * expected to check msg->reply before touching it.
527			 *
528			 * Return payload size.
529			 */
530			ret--;
531			memcpy(msg->buffer, rxbuf + 1, ret);
532		}
533		break;
534
535	default:
536		ret = -EINVAL;
537		break;
538	}
539
540	return ret;
541}
542
543static i915_reg_t vlv_aux_ctl_reg(struct intel_dp *intel_dp)
544{
545	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
546	enum aux_ch aux_ch = dig_port->aux_ch;
547
548	switch (aux_ch) {
549	case AUX_CH_B:
550	case AUX_CH_C:
551	case AUX_CH_D:
552		return VLV_DP_AUX_CH_CTL(aux_ch);
553	default:
554		MISSING_CASE(aux_ch);
555		return VLV_DP_AUX_CH_CTL(AUX_CH_B);
556	}
557}
558
559static i915_reg_t vlv_aux_data_reg(struct intel_dp *intel_dp, int index)
560{
561	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
562	enum aux_ch aux_ch = dig_port->aux_ch;
563
564	switch (aux_ch) {
565	case AUX_CH_B:
566	case AUX_CH_C:
567	case AUX_CH_D:
568		return VLV_DP_AUX_CH_DATA(aux_ch, index);
569	default:
570		MISSING_CASE(aux_ch);
571		return VLV_DP_AUX_CH_DATA(AUX_CH_B, index);
572	}
573}
574
575static i915_reg_t g4x_aux_ctl_reg(struct intel_dp *intel_dp)
576{
577	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
578	enum aux_ch aux_ch = dig_port->aux_ch;
579
580	switch (aux_ch) {
581	case AUX_CH_B:
582	case AUX_CH_C:
583	case AUX_CH_D:
584		return DP_AUX_CH_CTL(aux_ch);
585	default:
586		MISSING_CASE(aux_ch);
587		return DP_AUX_CH_CTL(AUX_CH_B);
588	}
589}
590
591static i915_reg_t g4x_aux_data_reg(struct intel_dp *intel_dp, int index)
592{
593	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
594	enum aux_ch aux_ch = dig_port->aux_ch;
595
596	switch (aux_ch) {
597	case AUX_CH_B:
598	case AUX_CH_C:
599	case AUX_CH_D:
600		return DP_AUX_CH_DATA(aux_ch, index);
601	default:
602		MISSING_CASE(aux_ch);
603		return DP_AUX_CH_DATA(AUX_CH_B, index);
604	}
605}
606
607static i915_reg_t ilk_aux_ctl_reg(struct intel_dp *intel_dp)
608{
609	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
610	enum aux_ch aux_ch = dig_port->aux_ch;
611
612	switch (aux_ch) {
613	case AUX_CH_A:
614		return DP_AUX_CH_CTL(aux_ch);
615	case AUX_CH_B:
616	case AUX_CH_C:
617	case AUX_CH_D:
618		return PCH_DP_AUX_CH_CTL(aux_ch);
619	default:
620		MISSING_CASE(aux_ch);
621		return DP_AUX_CH_CTL(AUX_CH_A);
622	}
623}
624
625static i915_reg_t ilk_aux_data_reg(struct intel_dp *intel_dp, int index)
626{
627	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
628	enum aux_ch aux_ch = dig_port->aux_ch;
629
630	switch (aux_ch) {
631	case AUX_CH_A:
632		return DP_AUX_CH_DATA(aux_ch, index);
633	case AUX_CH_B:
634	case AUX_CH_C:
635	case AUX_CH_D:
636		return PCH_DP_AUX_CH_DATA(aux_ch, index);
637	default:
638		MISSING_CASE(aux_ch);
639		return DP_AUX_CH_DATA(AUX_CH_A, index);
640	}
641}
642
643static i915_reg_t skl_aux_ctl_reg(struct intel_dp *intel_dp)
644{
645	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
646	enum aux_ch aux_ch = dig_port->aux_ch;
647
648	switch (aux_ch) {
649	case AUX_CH_A:
650	case AUX_CH_B:
651	case AUX_CH_C:
652	case AUX_CH_D:
653	case AUX_CH_E:
654	case AUX_CH_F:
655		return DP_AUX_CH_CTL(aux_ch);
656	default:
657		MISSING_CASE(aux_ch);
658		return DP_AUX_CH_CTL(AUX_CH_A);
659	}
660}
661
662static i915_reg_t skl_aux_data_reg(struct intel_dp *intel_dp, int index)
663{
664	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
665	enum aux_ch aux_ch = dig_port->aux_ch;
666
667	switch (aux_ch) {
668	case AUX_CH_A:
669	case AUX_CH_B:
670	case AUX_CH_C:
671	case AUX_CH_D:
672	case AUX_CH_E:
673	case AUX_CH_F:
674		return DP_AUX_CH_DATA(aux_ch, index);
675	default:
676		MISSING_CASE(aux_ch);
677		return DP_AUX_CH_DATA(AUX_CH_A, index);
678	}
679}
680
681static i915_reg_t tgl_aux_ctl_reg(struct intel_dp *intel_dp)
682{
683	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
684	enum aux_ch aux_ch = dig_port->aux_ch;
685
686	switch (aux_ch) {
687	case AUX_CH_A:
688	case AUX_CH_B:
689	case AUX_CH_C:
690	case AUX_CH_USBC1:
691	case AUX_CH_USBC2:
692	case AUX_CH_USBC3:
693	case AUX_CH_USBC4:
694	case AUX_CH_USBC5:  /* aka AUX_CH_D_XELPD */
695	case AUX_CH_USBC6:  /* aka AUX_CH_E_XELPD */
696		return DP_AUX_CH_CTL(aux_ch);
697	default:
698		MISSING_CASE(aux_ch);
699		return DP_AUX_CH_CTL(AUX_CH_A);
700	}
701}
702
703static i915_reg_t tgl_aux_data_reg(struct intel_dp *intel_dp, int index)
704{
705	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
706	enum aux_ch aux_ch = dig_port->aux_ch;
707
708	switch (aux_ch) {
709	case AUX_CH_A:
710	case AUX_CH_B:
711	case AUX_CH_C:
712	case AUX_CH_USBC1:
713	case AUX_CH_USBC2:
714	case AUX_CH_USBC3:
715	case AUX_CH_USBC4:
716	case AUX_CH_USBC5:  /* aka AUX_CH_D_XELPD */
717	case AUX_CH_USBC6:  /* aka AUX_CH_E_XELPD */
718		return DP_AUX_CH_DATA(aux_ch, index);
719	default:
720		MISSING_CASE(aux_ch);
721		return DP_AUX_CH_DATA(AUX_CH_A, index);
722	}
723}
724
725static i915_reg_t xelpdp_aux_ctl_reg(struct intel_dp *intel_dp)
726{
727	struct intel_display *display = to_intel_display(intel_dp);
728	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
729	enum aux_ch aux_ch = dig_port->aux_ch;
730
731	switch (aux_ch) {
732	case AUX_CH_A:
733	case AUX_CH_B:
734	case AUX_CH_USBC1:
735	case AUX_CH_USBC2:
736	case AUX_CH_USBC3:
737	case AUX_CH_USBC4:
738		return XELPDP_DP_AUX_CH_CTL(display, aux_ch);
739	default:
740		MISSING_CASE(aux_ch);
741		return XELPDP_DP_AUX_CH_CTL(display, AUX_CH_A);
742	}
743}
744
745static i915_reg_t xelpdp_aux_data_reg(struct intel_dp *intel_dp, int index)
746{
747	struct intel_display *display = to_intel_display(intel_dp);
748	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
749	enum aux_ch aux_ch = dig_port->aux_ch;
750
751	switch (aux_ch) {
752	case AUX_CH_A:
753	case AUX_CH_B:
754	case AUX_CH_USBC1:
755	case AUX_CH_USBC2:
756	case AUX_CH_USBC3:
757	case AUX_CH_USBC4:
758		return XELPDP_DP_AUX_CH_DATA(display, aux_ch, index);
759	default:
760		MISSING_CASE(aux_ch);
761		return XELPDP_DP_AUX_CH_DATA(display, AUX_CH_A, index);
762	}
763}
764
765void intel_dp_aux_fini(struct intel_dp *intel_dp)
766{
767	if (cpu_latency_qos_request_active(&intel_dp->pm_qos))
768		cpu_latency_qos_remove_request(&intel_dp->pm_qos);
769
770	kfree(intel_dp->aux.name);
771}
772
773void intel_dp_aux_init(struct intel_dp *intel_dp)
774{
775	struct intel_display *display = to_intel_display(intel_dp);
776	struct drm_i915_private *i915 = to_i915(display->drm);
777	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
778	struct intel_encoder *encoder = &dig_port->base;
779	enum aux_ch aux_ch = dig_port->aux_ch;
780	char buf[AUX_CH_NAME_BUFSIZE];
781
782	if (DISPLAY_VER(display) >= 14) {
783		intel_dp->aux_ch_ctl_reg = xelpdp_aux_ctl_reg;
784		intel_dp->aux_ch_data_reg = xelpdp_aux_data_reg;
785	} else if (DISPLAY_VER(display) >= 12) {
786		intel_dp->aux_ch_ctl_reg = tgl_aux_ctl_reg;
787		intel_dp->aux_ch_data_reg = tgl_aux_data_reg;
788	} else if (DISPLAY_VER(display) >= 9) {
789		intel_dp->aux_ch_ctl_reg = skl_aux_ctl_reg;
790		intel_dp->aux_ch_data_reg = skl_aux_data_reg;
791	} else if (HAS_PCH_SPLIT(i915)) {
792		intel_dp->aux_ch_ctl_reg = ilk_aux_ctl_reg;
793		intel_dp->aux_ch_data_reg = ilk_aux_data_reg;
794	} else if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) {
795		intel_dp->aux_ch_ctl_reg = vlv_aux_ctl_reg;
796		intel_dp->aux_ch_data_reg = vlv_aux_data_reg;
797	} else {
798		intel_dp->aux_ch_ctl_reg = g4x_aux_ctl_reg;
799		intel_dp->aux_ch_data_reg = g4x_aux_data_reg;
800	}
801
802	if (DISPLAY_VER(display) >= 9)
803		intel_dp->get_aux_clock_divider = skl_get_aux_clock_divider;
804	else if (IS_BROADWELL(i915) || IS_HASWELL(i915))
805		intel_dp->get_aux_clock_divider = hsw_get_aux_clock_divider;
806	else if (HAS_PCH_SPLIT(i915))
807		intel_dp->get_aux_clock_divider = ilk_get_aux_clock_divider;
808	else
809		intel_dp->get_aux_clock_divider = g4x_get_aux_clock_divider;
810
811	if (DISPLAY_VER(display) >= 9)
812		intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
813	else
814		intel_dp->get_aux_send_ctl = g4x_get_aux_send_ctl;
815
816	intel_dp->aux.drm_dev = display->drm;
817	drm_dp_aux_init(&intel_dp->aux);
818
819	/* Failure to allocate our preferred name is not critical */
820	intel_dp->aux.name = kasprintf(GFP_KERNEL, "AUX %s/%s",
821				       aux_ch_name(display, buf, sizeof(buf), aux_ch),
822				       encoder->base.name);
823
824	intel_dp->aux.transfer = intel_dp_aux_transfer;
825	cpu_latency_qos_add_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
826}
827
828static enum aux_ch default_aux_ch(struct intel_encoder *encoder)
829{
830	struct intel_display *display = to_intel_display(encoder);
831
832	/* SKL has DDI E but no AUX E */
833	if (DISPLAY_VER(display) == 9 && encoder->port == PORT_E)
834		return AUX_CH_A;
835
836	return (enum aux_ch)encoder->port;
837}
838
839static struct intel_encoder *
840get_encoder_by_aux_ch(struct intel_encoder *encoder,
841		      enum aux_ch aux_ch)
842{
843	struct intel_display *display = to_intel_display(encoder);
844	struct intel_encoder *other;
845
846	for_each_intel_encoder(display->drm, other) {
847		if (other == encoder)
848			continue;
849
850		if (!intel_encoder_is_dig_port(other))
851			continue;
852
853		if (enc_to_dig_port(other)->aux_ch == aux_ch)
854			return other;
855	}
856
857	return NULL;
858}
859
860enum aux_ch intel_dp_aux_ch(struct intel_encoder *encoder)
861{
862	struct intel_display *display = to_intel_display(encoder);
863	struct intel_encoder *other;
864	const char *source;
865	enum aux_ch aux_ch;
866	char buf[AUX_CH_NAME_BUFSIZE];
867
868	aux_ch = intel_bios_dp_aux_ch(encoder->devdata);
869	source = "VBT";
870
871	if (aux_ch == AUX_CH_NONE) {
872		aux_ch = default_aux_ch(encoder);
873		source = "platform default";
874	}
875
876	if (aux_ch == AUX_CH_NONE)
877		return AUX_CH_NONE;
878
879	/* FIXME validate aux_ch against platform caps */
880
881	other = get_encoder_by_aux_ch(encoder, aux_ch);
882	if (other) {
883		drm_dbg_kms(display->drm,
884			    "[ENCODER:%d:%s] AUX CH %s already claimed by [ENCODER:%d:%s]\n",
885			    encoder->base.base.id, encoder->base.name,
886			    aux_ch_name(display, buf, sizeof(buf), aux_ch),
887			    other->base.base.id, other->base.name);
888		return AUX_CH_NONE;
889	}
890
891	drm_dbg_kms(display->drm,
892		    "[ENCODER:%d:%s] Using AUX CH %s (%s)\n",
893		    encoder->base.base.id, encoder->base.name,
894		    aux_ch_name(display, buf, sizeof(buf), aux_ch), source);
895
896	return aux_ch;
897}
898
899void intel_dp_aux_irq_handler(struct intel_display *display)
900{
901	wake_up_all(&display->gmbus.wait_queue);
902}
v6.8
  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_aux.h"
 13#include "intel_dp_aux_regs.h"
 14#include "intel_pps.h"
 
 15#include "intel_tc.h"
 16
 17#define AUX_CH_NAME_BUFSIZE	6
 18
 19static const char *aux_ch_name(struct drm_i915_private *i915,
 20			       char *buf, int size, enum aux_ch aux_ch)
 21{
 22	if (DISPLAY_VER(i915) >= 13 && aux_ch >= AUX_CH_D_XELPD)
 23		snprintf(buf, size, "%c", 'A' + aux_ch - AUX_CH_D_XELPD + AUX_CH_D);
 24	else if (DISPLAY_VER(i915) >= 12 && aux_ch >= AUX_CH_USBC1)
 25		snprintf(buf, size, "USBC%c", '1' + aux_ch - AUX_CH_USBC1);
 26	else
 27		snprintf(buf, size, "%c", 'A' + aux_ch);
 28
 29	return buf;
 30}
 31
 32u32 intel_dp_aux_pack(const u8 *src, int src_bytes)
 33{
 34	int i;
 35	u32 v = 0;
 36
 37	if (src_bytes > 4)
 38		src_bytes = 4;
 39	for (i = 0; i < src_bytes; i++)
 40		v |= ((u32)src[i]) << ((3 - i) * 8);
 41	return v;
 42}
 43
 44static void intel_dp_aux_unpack(u32 src, u8 *dst, int dst_bytes)
 45{
 46	int i;
 47
 48	if (dst_bytes > 4)
 49		dst_bytes = 4;
 50	for (i = 0; i < dst_bytes; i++)
 51		dst[i] = src >> ((3 - i) * 8);
 52}
 53
 54static u32
 55intel_dp_aux_wait_done(struct intel_dp *intel_dp)
 56{
 57	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 58	i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
 59	const unsigned int timeout_ms = 10;
 60	u32 status;
 61	int ret;
 62
 63	ret = __intel_de_wait_for_register(i915, ch_ctl,
 64					   DP_AUX_CH_CTL_SEND_BUSY, 0,
 65					   2, timeout_ms, &status);
 66
 67	if (ret == -ETIMEDOUT)
 68		drm_err(&i915->drm,
 69			"%s: did not complete or timeout within %ums (status 0x%08x)\n",
 70			intel_dp->aux.name, timeout_ms, status);
 71
 72	return status;
 73}
 74
 75static u32 g4x_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
 76{
 77	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 78
 79	if (index)
 80		return 0;
 81
 82	/*
 83	 * The clock divider is based off the hrawclk, and would like to run at
 84	 * 2MHz.  So, take the hrawclk value and divide by 2000 and use that
 85	 */
 86	return DIV_ROUND_CLOSEST(RUNTIME_INFO(i915)->rawclk_freq, 2000);
 87}
 88
 89static u32 ilk_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
 90{
 91	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 92	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 93	u32 freq;
 94
 95	if (index)
 96		return 0;
 97
 98	/*
 99	 * The clock divider is based off the cdclk or PCH rawclk, and would
100	 * like to run at 2MHz.  So, take the cdclk or PCH rawclk value and
101	 * divide by 2000 and use that
102	 */
103	if (dig_port->aux_ch == AUX_CH_A)
104		freq = i915->display.cdclk.hw.cdclk;
105	else
106		freq = RUNTIME_INFO(i915)->rawclk_freq;
107	return DIV_ROUND_CLOSEST(freq, 2000);
108}
109
110static u32 hsw_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
111{
112	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 
113	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
114
115	if (dig_port->aux_ch != AUX_CH_A && HAS_PCH_LPT_H(i915)) {
116		/* Workaround for non-ULT HSW */
117		switch (index) {
118		case 0: return 63;
119		case 1: return 72;
120		default: return 0;
121		}
122	}
123
124	return ilk_get_aux_clock_divider(intel_dp, index);
125}
126
127static u32 skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
128{
129	/*
130	 * SKL doesn't need us to program the AUX clock divider (Hardware will
131	 * derive the clock from CDCLK automatically). We still implement the
132	 * get_aux_clock_divider vfunc to plug-in into the existing code.
133	 */
134	return index ? 0 : 1;
135}
136
137static int intel_dp_aux_sync_len(void)
138{
139	int precharge = 16; /* 10-16 */
140	int preamble = 16;
141
142	return precharge + preamble;
143}
144
145static int intel_dp_aux_fw_sync_len(void)
146{
147	int precharge = 10; /* 10-16 */
148	int preamble = 8;
149
 
 
 
 
 
 
 
 
 
 
 
150	return precharge + preamble;
151}
152
153static int g4x_dp_aux_precharge_len(void)
154{
155	int precharge_min = 10;
156	int preamble = 16;
157
158	/* HW wants the length of the extra precharge in 2us units */
159	return (intel_dp_aux_sync_len() -
160		precharge_min - preamble) / 2;
161}
162
163static u32 g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
164				int send_bytes,
165				u32 aux_clock_divider)
166{
167	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
168	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
169	u32 timeout;
170
171	/* Max timeout value on G4x-BDW: 1.6ms */
172	if (IS_BROADWELL(i915))
173		timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
174	else
175		timeout = DP_AUX_CH_CTL_TIME_OUT_400us;
176
177	return DP_AUX_CH_CTL_SEND_BUSY |
178		DP_AUX_CH_CTL_DONE |
179		DP_AUX_CH_CTL_INTERRUPT |
180		DP_AUX_CH_CTL_TIME_OUT_ERROR |
181		timeout |
182		DP_AUX_CH_CTL_RECEIVE_ERROR |
183		DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
184		DP_AUX_CH_CTL_PRECHARGE_2US(g4x_dp_aux_precharge_len()) |
185		DP_AUX_CH_CTL_BIT_CLOCK_2X(aux_clock_divider);
186}
187
188static u32 skl_get_aux_send_ctl(struct intel_dp *intel_dp,
189				int send_bytes,
190				u32 unused)
191{
 
192	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
193	struct drm_i915_private *i915 =	to_i915(dig_port->base.base.dev);
194	u32 ret;
195
196	/*
197	 * Max timeout values:
198	 * SKL-GLK: 1.6ms
199	 * ICL+: 4ms
200	 */
201	ret = DP_AUX_CH_CTL_SEND_BUSY |
202		DP_AUX_CH_CTL_DONE |
203		DP_AUX_CH_CTL_INTERRUPT |
204		DP_AUX_CH_CTL_TIME_OUT_ERROR |
205		DP_AUX_CH_CTL_TIME_OUT_MAX |
206		DP_AUX_CH_CTL_RECEIVE_ERROR |
207		DP_AUX_CH_CTL_MESSAGE_SIZE(send_bytes) |
208		DP_AUX_CH_CTL_FW_SYNC_PULSE_SKL(intel_dp_aux_fw_sync_len()) |
209		DP_AUX_CH_CTL_SYNC_PULSE_SKL(intel_dp_aux_sync_len());
210
211	if (intel_tc_port_in_tbt_alt_mode(dig_port))
212		ret |= DP_AUX_CH_CTL_TBT_IO;
213
214	/*
215	 * Power request bit is already set during aux power well enable.
216	 * Preserve the bit across aux transactions.
217	 */
218	if (DISPLAY_VER(i915) >= 14)
219		ret |= XELPDP_DP_AUX_CH_CTL_POWER_REQUEST;
220
221	return ret;
222}
223
224static int
225intel_dp_aux_xfer(struct intel_dp *intel_dp,
226		  const u8 *send, int send_bytes,
227		  u8 *recv, int recv_size,
228		  u32 aux_send_ctl_flags)
229{
 
230	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 
231	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
232	enum phy phy = intel_port_to_phy(i915, dig_port->base.port);
233	bool is_tc_port = intel_phy_is_tc(i915, phy);
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	if (is_tc_port) {
249		intel_tc_port_lock(dig_port);
250		/*
251		 * Abort transfers on a disconnected port as required by
252		 * DP 1.4a link CTS 4.2.1.5, also avoiding the long AUX
253		 * timeouts that would otherwise happen.
254		 * TODO: abort the transfer on non-TC ports as well.
255		 */
256		if (!intel_tc_port_connected_locked(&dig_port->base)) {
257			ret = -ENXIO;
258			goto out_unlock;
259		}
260	}
261
262	aux_domain = intel_aux_power_domain(dig_port);
263
264	aux_wakeref = intel_display_power_get(i915, aux_domain);
265	pps_wakeref = intel_pps_lock(intel_dp);
266
267	/*
268	 * We will be called with VDD already enabled for dpcd/edid/oui reads.
269	 * In such cases we want to leave VDD enabled and it's up to upper layers
270	 * to turn it off. But for eg. i2c-dev access we need to turn it on/off
271	 * ourselves.
272	 */
273	vdd = intel_pps_vdd_on_unlocked(intel_dp);
274
275	/*
276	 * dp aux is extremely sensitive to irq latency, hence request the
277	 * lowest possible wakeup latency and so prevent the cpu from going into
278	 * deep sleep states.
279	 */
280	cpu_latency_qos_update_request(&intel_dp->pm_qos, 0);
281
282	intel_pps_check_power_unlocked(intel_dp);
283
284	/*
285	 * FIXME PSR should be disabled here to prevent
286	 * it using the same AUX CH simultaneously
287	 */
288
289	/* Try to wait for any previous AUX channel activity */
290	for (try = 0; try < 3; try++) {
291		status = intel_de_read_notrace(i915, ch_ctl);
292		if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
293			break;
294		msleep(1);
295	}
296	/* just trace the final value */
297	trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);
298
299	if (try == 3) {
300		const u32 status = intel_de_read(i915, ch_ctl);
301
302		if (status != intel_dp->aux_busy_last_status) {
303			drm_WARN(&i915->drm, 1,
304				 "%s: not started (status 0x%08x)\n",
305				 intel_dp->aux.name, status);
306			intel_dp->aux_busy_last_status = status;
307		}
308
309		ret = -EBUSY;
310		goto out;
311	}
312
313	/* Only 5 data registers! */
314	if (drm_WARN_ON(&i915->drm, send_bytes > 20 || recv_size > 20)) {
315		ret = -E2BIG;
316		goto out;
317	}
318
319	while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
320		u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
321							  send_bytes,
322							  aux_clock_divider);
323
324		send_ctl |= aux_send_ctl_flags;
325
326		/* Must try at least 3 times according to DP spec */
327		for (try = 0; try < 5; try++) {
328			/* Load the send data into the aux channel data registers */
329			for (i = 0; i < send_bytes; i += 4)
330				intel_de_write(i915, ch_data[i >> 2],
331					       intel_dp_aux_pack(send + i,
332								 send_bytes - i));
333
334			/* Send the command and wait for it to complete */
335			intel_de_write(i915, ch_ctl, send_ctl);
336
337			status = intel_dp_aux_wait_done(intel_dp);
338
339			/* Clear done status and any errors */
340			intel_de_write(i915, ch_ctl,
341				       status | DP_AUX_CH_CTL_DONE |
342				       DP_AUX_CH_CTL_TIME_OUT_ERROR |
343				       DP_AUX_CH_CTL_RECEIVE_ERROR);
344
345			/*
346			 * DP CTS 1.2 Core Rev 1.1, 4.2.1.1 & 4.2.1.2
347			 *   400us delay required for errors and timeouts
348			 *   Timeout errors from the HW already meet this
349			 *   requirement so skip to next iteration
350			 */
351			if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR)
352				continue;
353
354			if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
355				usleep_range(400, 500);
356				continue;
357			}
358			if (status & DP_AUX_CH_CTL_DONE)
359				goto done;
360		}
361	}
362
363	if ((status & DP_AUX_CH_CTL_DONE) == 0) {
364		drm_err(&i915->drm, "%s: not done (status 0x%08x)\n",
365			intel_dp->aux.name, status);
366		ret = -EBUSY;
367		goto out;
368	}
369
370done:
371	/*
372	 * Check for timeout or receive error. Timeouts occur when the sink is
373	 * not connected.
374	 */
375	if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
376		drm_err(&i915->drm, "%s: receive error (status 0x%08x)\n",
377			intel_dp->aux.name, status);
378		ret = -EIO;
379		goto out;
380	}
381
382	/*
383	 * Timeouts occur when the device isn't connected, so they're "normal"
384	 * -- don't fill the kernel log with these
385	 */
386	if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
387		drm_dbg_kms(&i915->drm, "%s: timeout (status 0x%08x)\n",
388			    intel_dp->aux.name, status);
389		ret = -ETIMEDOUT;
390		goto out;
391	}
392
393	/* Unload any bytes sent back from the other side */
394	recv_bytes = REG_FIELD_GET(DP_AUX_CH_CTL_MESSAGE_SIZE_MASK, status);
395
396	/*
397	 * By BSpec: "Message sizes of 0 or >20 are not allowed."
398	 * We have no idea of what happened so we return -EBUSY so
399	 * drm layer takes care for the necessary retries.
400	 */
401	if (recv_bytes == 0 || recv_bytes > 20) {
402		drm_dbg_kms(&i915->drm,
403			    "%s: Forbidden recv_bytes = %d on aux transaction\n",
404			    intel_dp->aux.name, recv_bytes);
405		ret = -EBUSY;
406		goto out;
407	}
408
409	if (recv_bytes > recv_size)
410		recv_bytes = recv_size;
411
412	for (i = 0; i < recv_bytes; i += 4)
413		intel_dp_aux_unpack(intel_de_read(i915, ch_data[i >> 2]),
414				    recv + i, recv_bytes - i);
415
416	ret = recv_bytes;
417out:
418	cpu_latency_qos_update_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
419
420	if (vdd)
421		intel_pps_vdd_off_unlocked(intel_dp, false);
422
423	intel_pps_unlock(intel_dp, pps_wakeref);
424	intel_display_power_put_async(i915, aux_domain, aux_wakeref);
425out_unlock:
426	if (is_tc_port)
427		intel_tc_port_unlock(dig_port);
428
429	return ret;
430}
431
432#define BARE_ADDRESS_SIZE	3
433#define HEADER_SIZE		(BARE_ADDRESS_SIZE + 1)
434
435static void
436intel_dp_aux_header(u8 txbuf[HEADER_SIZE],
437		    const struct drm_dp_aux_msg *msg)
438{
439	txbuf[0] = (msg->request << 4) | ((msg->address >> 16) & 0xf);
440	txbuf[1] = (msg->address >> 8) & 0xff;
441	txbuf[2] = msg->address & 0xff;
442	txbuf[3] = msg->size - 1;
443}
444
445static u32 intel_dp_aux_xfer_flags(const struct drm_dp_aux_msg *msg)
446{
447	/*
448	 * If we're trying to send the HDCP Aksv, we need to set a the Aksv
449	 * select bit to inform the hardware to send the Aksv after our header
450	 * since we can't access that data from software.
451	 */
452	if ((msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_NATIVE_WRITE &&
453	    msg->address == DP_AUX_HDCP_AKSV)
454		return DP_AUX_CH_CTL_AUX_AKSV_SELECT;
455
456	return 0;
457}
458
459static ssize_t
460intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
461{
462	struct intel_dp *intel_dp = container_of(aux, struct intel_dp, aux);
463	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
464	u8 txbuf[20], rxbuf[20];
465	size_t txsize, rxsize;
466	u32 flags = intel_dp_aux_xfer_flags(msg);
467	int ret;
468
469	intel_dp_aux_header(txbuf, msg);
470
471	switch (msg->request & ~DP_AUX_I2C_MOT) {
472	case DP_AUX_NATIVE_WRITE:
473	case DP_AUX_I2C_WRITE:
474	case DP_AUX_I2C_WRITE_STATUS_UPDATE:
475		txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
476		rxsize = 2; /* 0 or 1 data bytes */
477
478		if (drm_WARN_ON(&i915->drm, txsize > 20))
479			return -E2BIG;
480
481		drm_WARN_ON(&i915->drm, !msg->buffer != !msg->size);
482
483		if (msg->buffer)
484			memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);
485
486		ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
487					rxbuf, rxsize, flags);
488		if (ret > 0) {
489			msg->reply = rxbuf[0] >> 4;
490
491			if (ret > 1) {
492				/* Number of bytes written in a short write. */
493				ret = clamp_t(int, rxbuf[1], 0, msg->size);
494			} else {
495				/* Return payload size. */
496				ret = msg->size;
497			}
498		}
499		break;
500
501	case DP_AUX_NATIVE_READ:
502	case DP_AUX_I2C_READ:
503		txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
504		rxsize = msg->size + 1;
505
506		if (drm_WARN_ON(&i915->drm, rxsize > 20))
507			return -E2BIG;
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			 * Assume happy day, and copy the data. The caller is
515			 * expected to check msg->reply before touching it.
516			 *
517			 * Return payload size.
518			 */
519			ret--;
520			memcpy(msg->buffer, rxbuf + 1, ret);
521		}
522		break;
523
524	default:
525		ret = -EINVAL;
526		break;
527	}
528
529	return ret;
530}
531
532static i915_reg_t vlv_aux_ctl_reg(struct intel_dp *intel_dp)
533{
534	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
535	enum aux_ch aux_ch = dig_port->aux_ch;
536
537	switch (aux_ch) {
538	case AUX_CH_B:
539	case AUX_CH_C:
540	case AUX_CH_D:
541		return VLV_DP_AUX_CH_CTL(aux_ch);
542	default:
543		MISSING_CASE(aux_ch);
544		return VLV_DP_AUX_CH_CTL(AUX_CH_B);
545	}
546}
547
548static i915_reg_t vlv_aux_data_reg(struct intel_dp *intel_dp, int index)
549{
550	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
551	enum aux_ch aux_ch = dig_port->aux_ch;
552
553	switch (aux_ch) {
554	case AUX_CH_B:
555	case AUX_CH_C:
556	case AUX_CH_D:
557		return VLV_DP_AUX_CH_DATA(aux_ch, index);
558	default:
559		MISSING_CASE(aux_ch);
560		return VLV_DP_AUX_CH_DATA(AUX_CH_B, index);
561	}
562}
563
564static i915_reg_t g4x_aux_ctl_reg(struct intel_dp *intel_dp)
565{
566	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
567	enum aux_ch aux_ch = dig_port->aux_ch;
568
569	switch (aux_ch) {
570	case AUX_CH_B:
571	case AUX_CH_C:
572	case AUX_CH_D:
573		return DP_AUX_CH_CTL(aux_ch);
574	default:
575		MISSING_CASE(aux_ch);
576		return DP_AUX_CH_CTL(AUX_CH_B);
577	}
578}
579
580static i915_reg_t g4x_aux_data_reg(struct intel_dp *intel_dp, int index)
581{
582	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
583	enum aux_ch aux_ch = dig_port->aux_ch;
584
585	switch (aux_ch) {
586	case AUX_CH_B:
587	case AUX_CH_C:
588	case AUX_CH_D:
589		return DP_AUX_CH_DATA(aux_ch, index);
590	default:
591		MISSING_CASE(aux_ch);
592		return DP_AUX_CH_DATA(AUX_CH_B, index);
593	}
594}
595
596static i915_reg_t ilk_aux_ctl_reg(struct intel_dp *intel_dp)
597{
598	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
599	enum aux_ch aux_ch = dig_port->aux_ch;
600
601	switch (aux_ch) {
602	case AUX_CH_A:
603		return DP_AUX_CH_CTL(aux_ch);
604	case AUX_CH_B:
605	case AUX_CH_C:
606	case AUX_CH_D:
607		return PCH_DP_AUX_CH_CTL(aux_ch);
608	default:
609		MISSING_CASE(aux_ch);
610		return DP_AUX_CH_CTL(AUX_CH_A);
611	}
612}
613
614static i915_reg_t ilk_aux_data_reg(struct intel_dp *intel_dp, int index)
615{
616	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
617	enum aux_ch aux_ch = dig_port->aux_ch;
618
619	switch (aux_ch) {
620	case AUX_CH_A:
621		return DP_AUX_CH_DATA(aux_ch, index);
622	case AUX_CH_B:
623	case AUX_CH_C:
624	case AUX_CH_D:
625		return PCH_DP_AUX_CH_DATA(aux_ch, index);
626	default:
627		MISSING_CASE(aux_ch);
628		return DP_AUX_CH_DATA(AUX_CH_A, index);
629	}
630}
631
632static i915_reg_t skl_aux_ctl_reg(struct intel_dp *intel_dp)
633{
634	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
635	enum aux_ch aux_ch = dig_port->aux_ch;
636
637	switch (aux_ch) {
638	case AUX_CH_A:
639	case AUX_CH_B:
640	case AUX_CH_C:
641	case AUX_CH_D:
642	case AUX_CH_E:
643	case AUX_CH_F:
644		return DP_AUX_CH_CTL(aux_ch);
645	default:
646		MISSING_CASE(aux_ch);
647		return DP_AUX_CH_CTL(AUX_CH_A);
648	}
649}
650
651static i915_reg_t skl_aux_data_reg(struct intel_dp *intel_dp, int index)
652{
653	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
654	enum aux_ch aux_ch = dig_port->aux_ch;
655
656	switch (aux_ch) {
657	case AUX_CH_A:
658	case AUX_CH_B:
659	case AUX_CH_C:
660	case AUX_CH_D:
661	case AUX_CH_E:
662	case AUX_CH_F:
663		return DP_AUX_CH_DATA(aux_ch, index);
664	default:
665		MISSING_CASE(aux_ch);
666		return DP_AUX_CH_DATA(AUX_CH_A, index);
667	}
668}
669
670static i915_reg_t tgl_aux_ctl_reg(struct intel_dp *intel_dp)
671{
672	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
673	enum aux_ch aux_ch = dig_port->aux_ch;
674
675	switch (aux_ch) {
676	case AUX_CH_A:
677	case AUX_CH_B:
678	case AUX_CH_C:
679	case AUX_CH_USBC1:
680	case AUX_CH_USBC2:
681	case AUX_CH_USBC3:
682	case AUX_CH_USBC4:
683	case AUX_CH_USBC5:  /* aka AUX_CH_D_XELPD */
684	case AUX_CH_USBC6:  /* aka AUX_CH_E_XELPD */
685		return DP_AUX_CH_CTL(aux_ch);
686	default:
687		MISSING_CASE(aux_ch);
688		return DP_AUX_CH_CTL(AUX_CH_A);
689	}
690}
691
692static i915_reg_t tgl_aux_data_reg(struct intel_dp *intel_dp, int index)
693{
694	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
695	enum aux_ch aux_ch = dig_port->aux_ch;
696
697	switch (aux_ch) {
698	case AUX_CH_A:
699	case AUX_CH_B:
700	case AUX_CH_C:
701	case AUX_CH_USBC1:
702	case AUX_CH_USBC2:
703	case AUX_CH_USBC3:
704	case AUX_CH_USBC4:
705	case AUX_CH_USBC5:  /* aka AUX_CH_D_XELPD */
706	case AUX_CH_USBC6:  /* aka AUX_CH_E_XELPD */
707		return DP_AUX_CH_DATA(aux_ch, index);
708	default:
709		MISSING_CASE(aux_ch);
710		return DP_AUX_CH_DATA(AUX_CH_A, index);
711	}
712}
713
714static i915_reg_t xelpdp_aux_ctl_reg(struct intel_dp *intel_dp)
715{
716	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
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_USBC1:
724	case AUX_CH_USBC2:
725	case AUX_CH_USBC3:
726	case AUX_CH_USBC4:
727		return XELPDP_DP_AUX_CH_CTL(i915, aux_ch);
728	default:
729		MISSING_CASE(aux_ch);
730		return XELPDP_DP_AUX_CH_CTL(i915, AUX_CH_A);
731	}
732}
733
734static i915_reg_t xelpdp_aux_data_reg(struct intel_dp *intel_dp, int index)
735{
736	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
737	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
738	enum aux_ch aux_ch = dig_port->aux_ch;
739
740	switch (aux_ch) {
741	case AUX_CH_A:
742	case AUX_CH_B:
743	case AUX_CH_USBC1:
744	case AUX_CH_USBC2:
745	case AUX_CH_USBC3:
746	case AUX_CH_USBC4:
747		return XELPDP_DP_AUX_CH_DATA(i915, aux_ch, index);
748	default:
749		MISSING_CASE(aux_ch);
750		return XELPDP_DP_AUX_CH_DATA(i915, AUX_CH_A, index);
751	}
752}
753
754void intel_dp_aux_fini(struct intel_dp *intel_dp)
755{
756	if (cpu_latency_qos_request_active(&intel_dp->pm_qos))
757		cpu_latency_qos_remove_request(&intel_dp->pm_qos);
758
759	kfree(intel_dp->aux.name);
760}
761
762void intel_dp_aux_init(struct intel_dp *intel_dp)
763{
764	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 
765	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
766	struct intel_encoder *encoder = &dig_port->base;
767	enum aux_ch aux_ch = dig_port->aux_ch;
768	char buf[AUX_CH_NAME_BUFSIZE];
769
770	if (DISPLAY_VER(i915) >= 14) {
771		intel_dp->aux_ch_ctl_reg = xelpdp_aux_ctl_reg;
772		intel_dp->aux_ch_data_reg = xelpdp_aux_data_reg;
773	} else if (DISPLAY_VER(i915) >= 12) {
774		intel_dp->aux_ch_ctl_reg = tgl_aux_ctl_reg;
775		intel_dp->aux_ch_data_reg = tgl_aux_data_reg;
776	} else if (DISPLAY_VER(i915) >= 9) {
777		intel_dp->aux_ch_ctl_reg = skl_aux_ctl_reg;
778		intel_dp->aux_ch_data_reg = skl_aux_data_reg;
779	} else if (HAS_PCH_SPLIT(i915)) {
780		intel_dp->aux_ch_ctl_reg = ilk_aux_ctl_reg;
781		intel_dp->aux_ch_data_reg = ilk_aux_data_reg;
782	} else if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) {
783		intel_dp->aux_ch_ctl_reg = vlv_aux_ctl_reg;
784		intel_dp->aux_ch_data_reg = vlv_aux_data_reg;
785	} else {
786		intel_dp->aux_ch_ctl_reg = g4x_aux_ctl_reg;
787		intel_dp->aux_ch_data_reg = g4x_aux_data_reg;
788	}
789
790	if (DISPLAY_VER(i915) >= 9)
791		intel_dp->get_aux_clock_divider = skl_get_aux_clock_divider;
792	else if (IS_BROADWELL(i915) || IS_HASWELL(i915))
793		intel_dp->get_aux_clock_divider = hsw_get_aux_clock_divider;
794	else if (HAS_PCH_SPLIT(i915))
795		intel_dp->get_aux_clock_divider = ilk_get_aux_clock_divider;
796	else
797		intel_dp->get_aux_clock_divider = g4x_get_aux_clock_divider;
798
799	if (DISPLAY_VER(i915) >= 9)
800		intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
801	else
802		intel_dp->get_aux_send_ctl = g4x_get_aux_send_ctl;
803
804	intel_dp->aux.drm_dev = &i915->drm;
805	drm_dp_aux_init(&intel_dp->aux);
806
807	/* Failure to allocate our preferred name is not critical */
808	intel_dp->aux.name = kasprintf(GFP_KERNEL, "AUX %s/%s",
809				       aux_ch_name(i915, buf, sizeof(buf), aux_ch),
810				       encoder->base.name);
811
812	intel_dp->aux.transfer = intel_dp_aux_transfer;
813	cpu_latency_qos_add_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
814}
815
816static enum aux_ch default_aux_ch(struct intel_encoder *encoder)
817{
818	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
819
820	/* SKL has DDI E but no AUX E */
821	if (DISPLAY_VER(i915) == 9 && encoder->port == PORT_E)
822		return AUX_CH_A;
823
824	return (enum aux_ch)encoder->port;
825}
826
827static struct intel_encoder *
828get_encoder_by_aux_ch(struct intel_encoder *encoder,
829		      enum aux_ch aux_ch)
830{
831	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
832	struct intel_encoder *other;
833
834	for_each_intel_encoder(&i915->drm, other) {
835		if (other == encoder)
836			continue;
837
838		if (!intel_encoder_is_dig_port(other))
839			continue;
840
841		if (enc_to_dig_port(other)->aux_ch == aux_ch)
842			return other;
843	}
844
845	return NULL;
846}
847
848enum aux_ch intel_dp_aux_ch(struct intel_encoder *encoder)
849{
850	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
851	struct intel_encoder *other;
852	const char *source;
853	enum aux_ch aux_ch;
854	char buf[AUX_CH_NAME_BUFSIZE];
855
856	aux_ch = intel_bios_dp_aux_ch(encoder->devdata);
857	source = "VBT";
858
859	if (aux_ch == AUX_CH_NONE) {
860		aux_ch = default_aux_ch(encoder);
861		source = "platform default";
862	}
863
864	if (aux_ch == AUX_CH_NONE)
865		return AUX_CH_NONE;
866
867	/* FIXME validate aux_ch against platform caps */
868
869	other = get_encoder_by_aux_ch(encoder, aux_ch);
870	if (other) {
871		drm_dbg_kms(&i915->drm,
872			    "[ENCODER:%d:%s] AUX CH %s already claimed by [ENCODER:%d:%s]\n",
873			    encoder->base.base.id, encoder->base.name,
874			    aux_ch_name(i915, buf, sizeof(buf), aux_ch),
875			    other->base.base.id, other->base.name);
876		return AUX_CH_NONE;
877	}
878
879	drm_dbg_kms(&i915->drm,
880		    "[ENCODER:%d:%s] Using AUX CH %s (%s)\n",
881		    encoder->base.base.id, encoder->base.name,
882		    aux_ch_name(i915, buf, sizeof(buf), aux_ch), source);
883
884	return aux_ch;
885}
886
887void intel_dp_aux_irq_handler(struct drm_i915_private *i915)
888{
889	wake_up_all(&i915->display.gmbus.wait_queue);
890}