1 /*
2  * Copyright 2012-15 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: AMD
23  *
24  */
25 
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 
29 #include "dm_services.h"
30 #include "core_types.h"
31 #include "dce_aux.h"
32 #include "dce/dce_11_0_sh_mask.h"
33 #include "dm_event_log.h"
34 #include "dm_helpers.h"
35 #include "dmub/inc/dmub_cmd.h"
36 
37 #define CTX \
38 	aux110->base.ctx
39 #define REG(reg_name)\
40 	(aux110->regs->reg_name)
41 
42 #define DC_LOGGER \
43 	engine->ctx->logger
44 
45 #define DC_TRACE_LEVEL_MESSAGE(...) do { } while (0)
46 #define IS_DC_I2CAUX_LOGGING_ENABLED() (false)
47 #define LOG_FLAG_Error_I2cAux LOG_ERROR
48 #define LOG_FLAG_I2cAux_DceAux LOG_I2C_AUX
49 
50 #include "reg_helper.h"
51 
52 #undef FN
53 #define FN(reg_name, field_name) \
54 	aux110->shift->field_name, aux110->mask->field_name
55 
56 #define FROM_AUX_ENGINE(ptr) \
57 	container_of((ptr), struct aux_engine_dce110, base)
58 
59 #define FROM_ENGINE(ptr) \
60 	FROM_AUX_ENGINE(container_of((ptr), struct dce_aux, base))
61 
62 #define FROM_AUX_ENGINE_ENGINE(ptr) \
63 	container_of((ptr), struct dce_aux, base)
64 enum {
65 	AUX_INVALID_REPLY_RETRY_COUNTER = 1,
66 	AUX_TIMED_OUT_RETRY_COUNTER = 2,
67 	AUX_DEFER_RETRY_COUNTER = 6
68 };
69 
70 #define TIME_OUT_INCREMENT        1016
71 #define TIME_OUT_MULTIPLIER_8     8
72 #define TIME_OUT_MULTIPLIER_16    16
73 #define TIME_OUT_MULTIPLIER_32    32
74 #define TIME_OUT_MULTIPLIER_64    64
75 #define MAX_TIMEOUT_LENGTH        127
76 #define DEFAULT_AUX_ENGINE_MULT   0
77 #define DEFAULT_AUX_ENGINE_LENGTH 69
78 
79 #define DC_TRACE_LEVEL_MESSAGE(...) do { } while (0)
80 
81 static void release_engine(
82 	struct dce_aux *engine)
83 {
84 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
85 
86 	dal_ddc_close(engine->ddc);
87 
88 	engine->ddc = NULL;
89 
90 	REG_UPDATE(AUX_ARB_CONTROL, AUX_SW_DONE_USING_AUX_REG, 1);
91 }
92 
93 #define SW_CAN_ACCESS_AUX 1
94 #define DMCU_CAN_ACCESS_AUX 2
95 
96 static bool is_engine_available(
97 	struct dce_aux *engine)
98 {
99 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
100 
101 	uint32_t value = REG_READ(AUX_ARB_CONTROL);
102 	uint32_t field = get_reg_field_value(
103 			value,
104 			AUX_ARB_CONTROL,
105 			AUX_REG_RW_CNTL_STATUS);
106 
107 	return (field != DMCU_CAN_ACCESS_AUX);
108 }
109 static bool acquire_engine(
110 	struct dce_aux *engine)
111 {
112 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
113 
114 	uint32_t value = REG_READ(AUX_ARB_CONTROL);
115 	uint32_t field = get_reg_field_value(
116 			value,
117 			AUX_ARB_CONTROL,
118 			AUX_REG_RW_CNTL_STATUS);
119 	if (field == DMCU_CAN_ACCESS_AUX)
120 		return false;
121 	/* enable AUX before request SW to access AUX */
122 	value = REG_READ(AUX_CONTROL);
123 	field = get_reg_field_value(value,
124 				AUX_CONTROL,
125 				AUX_EN);
126 
127 	if (field == 0) {
128 		set_reg_field_value(
129 				value,
130 				1,
131 				AUX_CONTROL,
132 				AUX_EN);
133 
134 		if (REG(AUX_RESET_MASK)) {
135 			/*DP_AUX block as part of the enable sequence*/
136 			set_reg_field_value(
137 				value,
138 				1,
139 				AUX_CONTROL,
140 				AUX_RESET);
141 		}
142 
143 		REG_WRITE(AUX_CONTROL, value);
144 
145 		if (REG(AUX_RESET_MASK)) {
146 			/*poll HW to make sure reset it done*/
147 
148 			REG_WAIT(AUX_CONTROL, AUX_RESET_DONE, 1,
149 					1, 11);
150 
151 			set_reg_field_value(
152 				value,
153 				0,
154 				AUX_CONTROL,
155 				AUX_RESET);
156 
157 			REG_WRITE(AUX_CONTROL, value);
158 
159 			REG_WAIT(AUX_CONTROL, AUX_RESET_DONE, 0,
160 					1, 11);
161 		}
162 	} /*if (field)*/
163 
164 	/* request SW to access AUX */
165 	REG_UPDATE(AUX_ARB_CONTROL, AUX_SW_USE_AUX_REG_REQ, 1);
166 
167 	value = REG_READ(AUX_ARB_CONTROL);
168 	field = get_reg_field_value(
169 			value,
170 			AUX_ARB_CONTROL,
171 			AUX_REG_RW_CNTL_STATUS);
172 
173 	return (field == SW_CAN_ACCESS_AUX);
174 }
175 
176 #define COMPOSE_AUX_SW_DATA_16_20(command, address) \
177 	((command) | ((0xF0000 & (address)) >> 16))
178 
179 #define COMPOSE_AUX_SW_DATA_8_15(address) \
180 	((0xFF00 & (address)) >> 8)
181 
182 #define COMPOSE_AUX_SW_DATA_0_7(address) \
183 	(0xFF & (address))
184 
185 static void submit_channel_request(
186 	struct dce_aux *engine,
187 	struct aux_request_transaction_data *request)
188 {
189 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
190 	uint32_t value;
191 	uint32_t length;
192 
193 	bool is_write =
194 		((request->type == AUX_TRANSACTION_TYPE_DP) &&
195 		 (request->action == I2CAUX_TRANSACTION_ACTION_DP_WRITE)) ||
196 		((request->type == AUX_TRANSACTION_TYPE_I2C) &&
197 		((request->action == I2CAUX_TRANSACTION_ACTION_I2C_WRITE) ||
198 		 (request->action == I2CAUX_TRANSACTION_ACTION_I2C_WRITE_MOT)));
199 	if (REG(AUXN_IMPCAL)) {
200 		/* clear_aux_error */
201 		REG_UPDATE_SEQ_2(AUXN_IMPCAL,
202 				AUXN_CALOUT_ERROR_AK, 1,
203 				AUXN_CALOUT_ERROR_AK, 0);
204 
205 		REG_UPDATE_SEQ_2(AUXP_IMPCAL,
206 				AUXP_CALOUT_ERROR_AK, 1,
207 				AUXP_CALOUT_ERROR_AK, 0);
208 
209 		/* force_default_calibrate */
210 		REG_UPDATE_SEQ_2(AUXN_IMPCAL,
211 				AUXN_IMPCAL_ENABLE, 1,
212 				AUXN_IMPCAL_OVERRIDE_ENABLE, 0);
213 
214 		/* bug? why AUXN update EN and OVERRIDE_EN 1 by 1 while AUX P toggles OVERRIDE? */
215 
216 		REG_UPDATE_SEQ_2(AUXP_IMPCAL,
217 				AUXP_IMPCAL_OVERRIDE_ENABLE, 1,
218 				AUXP_IMPCAL_OVERRIDE_ENABLE, 0);
219 	}
220 
221 	REG_UPDATE(AUX_INTERRUPT_CONTROL, AUX_SW_DONE_ACK, 1);
222 
223 	REG_WAIT(AUX_SW_STATUS, AUX_SW_DONE, 0,
224 				10, aux110->polling_timeout_period/10);
225 
226 	/* set the delay and the number of bytes to write */
227 
228 	/* The length include
229 	 * the 4 bit header and the 20 bit address
230 	 * (that is 3 byte).
231 	 * If the requested length is non zero this means
232 	 * an addition byte specifying the length is required.
233 	 */
234 
235 	length = request->length ? 4 : 3;
236 	if (is_write)
237 		length += request->length;
238 
239 	REG_UPDATE_2(AUX_SW_CONTROL,
240 			AUX_SW_START_DELAY, request->delay,
241 			AUX_SW_WR_BYTES, length);
242 
243 	/* program action and address and payload data (if 'is_write') */
244 	value = REG_UPDATE_4(AUX_SW_DATA,
245 			AUX_SW_INDEX, 0,
246 			AUX_SW_DATA_RW, 0,
247 			AUX_SW_AUTOINCREMENT_DISABLE, 1,
248 			AUX_SW_DATA, COMPOSE_AUX_SW_DATA_16_20(request->action, request->address));
249 
250 	value = REG_SET_2(AUX_SW_DATA, value,
251 			AUX_SW_AUTOINCREMENT_DISABLE, 0,
252 			AUX_SW_DATA, COMPOSE_AUX_SW_DATA_8_15(request->address));
253 
254 	value = REG_SET(AUX_SW_DATA, value,
255 			AUX_SW_DATA, COMPOSE_AUX_SW_DATA_0_7(request->address));
256 
257 	if (request->length) {
258 		value = REG_SET(AUX_SW_DATA, value,
259 				AUX_SW_DATA, request->length - 1);
260 	}
261 
262 	if (is_write) {
263 		/* Load the HW buffer with the Data to be sent.
264 		 * This is relevant for write operation.
265 		 * For read, the data recived data will be
266 		 * processed in process_channel_reply().
267 		 */
268 		uint32_t i = 0;
269 
270 		while (i < request->length) {
271 			value = REG_SET(AUX_SW_DATA, value,
272 					AUX_SW_DATA, request->data[i]);
273 
274 			++i;
275 		}
276 	}
277 
278 	REG_UPDATE(AUX_SW_CONTROL, AUX_SW_GO, 1);
279 	EVENT_LOG_AUX_REQ(engine->ddc->pin_data->en, EVENT_LOG_AUX_ORIGIN_NATIVE,
280 					request->action, request->address, request->length, request->data);
281 }
282 
283 static int read_channel_reply(struct dce_aux *engine, uint32_t size,
284 			      uint8_t *buffer, uint8_t *reply_result,
285 			      uint32_t *sw_status)
286 {
287 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
288 	uint32_t bytes_replied;
289 	uint32_t reply_result_32;
290 
291 	*sw_status = REG_GET(AUX_SW_STATUS, AUX_SW_REPLY_BYTE_COUNT,
292 			     &bytes_replied);
293 
294 	/* In case HPD is LOW, exit AUX transaction */
295 	if ((*sw_status & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK))
296 		return -1;
297 
298 	/* Need at least the status byte */
299 	if (!bytes_replied)
300 		return -1;
301 
302 	REG_UPDATE_SEQ_3(AUX_SW_DATA,
303 			  AUX_SW_INDEX, 0,
304 			  AUX_SW_AUTOINCREMENT_DISABLE, 1,
305 			  AUX_SW_DATA_RW, 1);
306 
307 	REG_GET(AUX_SW_DATA, AUX_SW_DATA, &reply_result_32);
308 	reply_result_32 = reply_result_32 >> 4;
309 	if (reply_result != NULL)
310 		*reply_result = (uint8_t)reply_result_32;
311 
312 	if (reply_result_32 == 0) { /* ACK */
313 		uint32_t i = 0;
314 
315 		/* First byte was already used to get the command status */
316 		--bytes_replied;
317 
318 		/* Do not overflow buffer */
319 		if (bytes_replied > size)
320 			return -1;
321 
322 		while (i < bytes_replied) {
323 			uint32_t aux_sw_data_val;
324 
325 			REG_GET(AUX_SW_DATA, AUX_SW_DATA, &aux_sw_data_val);
326 			buffer[i] = aux_sw_data_val;
327 			++i;
328 		}
329 
330 		return i;
331 	}
332 
333 	return 0;
334 }
335 
336 static enum aux_return_code_type get_channel_status(
337 	struct dce_aux *engine,
338 	uint8_t *returned_bytes)
339 {
340 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
341 
342 	uint32_t value;
343 
344 	if (returned_bytes == NULL) {
345 		/*caller pass NULL pointer*/
346 		ASSERT_CRITICAL(false);
347 		return AUX_RET_ERROR_UNKNOWN;
348 	}
349 	*returned_bytes = 0;
350 
351 	/* poll to make sure that SW_DONE is asserted */
352 	REG_WAIT(AUX_SW_STATUS, AUX_SW_DONE, 1,
353 				10, aux110->polling_timeout_period/10);
354 
355 	value = REG_READ(AUX_SW_STATUS);
356 	/* in case HPD is LOW, exit AUX transaction */
357 	if ((value & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK))
358 		return AUX_RET_ERROR_HPD_DISCON;
359 
360 	/* Note that the following bits are set in 'status.bits'
361 	 * during CTS 4.2.1.2 (FW 3.3.1):
362 	 * AUX_SW_RX_MIN_COUNT_VIOL, AUX_SW_RX_INVALID_STOP,
363 	 * AUX_SW_RX_RECV_NO_DET, AUX_SW_RX_RECV_INVALID_H.
364 	 *
365 	 * AUX_SW_RX_MIN_COUNT_VIOL is an internal,
366 	 * HW debugging bit and should be ignored.
367 	 */
368 	if (value & AUX_SW_STATUS__AUX_SW_DONE_MASK) {
369 		if ((value & AUX_SW_STATUS__AUX_SW_RX_TIMEOUT_STATE_MASK) ||
370 			(value & AUX_SW_STATUS__AUX_SW_RX_TIMEOUT_MASK))
371 			return AUX_RET_ERROR_TIMEOUT;
372 
373 		else if ((value & AUX_SW_STATUS__AUX_SW_RX_INVALID_STOP_MASK) ||
374 			(value & AUX_SW_STATUS__AUX_SW_RX_RECV_NO_DET_MASK) ||
375 			(value &
376 				AUX_SW_STATUS__AUX_SW_RX_RECV_INVALID_H_MASK) ||
377 			(value & AUX_SW_STATUS__AUX_SW_RX_RECV_INVALID_L_MASK))
378 			return AUX_RET_ERROR_INVALID_REPLY;
379 
380 		*returned_bytes = get_reg_field_value(value,
381 				AUX_SW_STATUS,
382 				AUX_SW_REPLY_BYTE_COUNT);
383 
384 		if (*returned_bytes == 0)
385 			return
386 			AUX_RET_ERROR_INVALID_REPLY;
387 		else {
388 			*returned_bytes -= 1;
389 			return AUX_RET_SUCCESS;
390 		}
391 	} else {
392 		/*time_elapsed >= aux_engine->timeout_period
393 		 *  AUX_SW_STATUS__AUX_SW_HPD_DISCON = at this point
394 		 */
395 		ASSERT_CRITICAL(false);
396 		return AUX_RET_ERROR_TIMEOUT;
397 	}
398 }
399 
400 static bool acquire(
401 	struct dce_aux *engine,
402 	struct ddc *ddc)
403 {
404 	enum gpio_result result;
405 
406 	if ((engine == NULL) || !is_engine_available(engine))
407 		return false;
408 
409 	result = dal_ddc_open(ddc, GPIO_MODE_HARDWARE,
410 		GPIO_DDC_CONFIG_TYPE_MODE_AUX);
411 
412 	if (result != GPIO_RESULT_OK)
413 		return false;
414 
415 	if (!acquire_engine(engine)) {
416 		dal_ddc_close(ddc);
417 		return false;
418 	}
419 
420 	engine->ddc = ddc;
421 
422 	return true;
423 }
424 
425 void dce110_engine_destroy(struct dce_aux **engine)
426 {
427 
428 	struct aux_engine_dce110 *engine110 = FROM_AUX_ENGINE(*engine);
429 
430 	kfree(engine110);
431 	*engine = NULL;
432 
433 }
434 
435 static uint32_t dce_aux_configure_timeout(struct ddc_service *ddc,
436 		uint32_t timeout_in_us)
437 {
438 	uint32_t multiplier = 0;
439 	uint32_t length = 0;
440 	uint32_t prev_length = 0;
441 	uint32_t prev_mult = 0;
442 	uint32_t prev_timeout_val = 0;
443 	struct ddc *ddc_pin = ddc->ddc_pin;
444 	struct dce_aux *aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
445 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(aux_engine);
446 
447 	/* 1-Update polling timeout period */
448 	aux110->polling_timeout_period = timeout_in_us * SW_AUX_TIMEOUT_PERIOD_MULTIPLIER;
449 
450 	/* 2-Update aux timeout period length and multiplier */
451 	if (timeout_in_us == 0) {
452 		multiplier = DEFAULT_AUX_ENGINE_MULT;
453 		length = DEFAULT_AUX_ENGINE_LENGTH;
454 	} else if (timeout_in_us <= TIME_OUT_INCREMENT) {
455 		multiplier = 0;
456 		length = timeout_in_us/TIME_OUT_MULTIPLIER_8;
457 		if (timeout_in_us % TIME_OUT_MULTIPLIER_8 != 0)
458 			length++;
459 	} else if (timeout_in_us <= 2 * TIME_OUT_INCREMENT) {
460 		multiplier = 1;
461 		length = timeout_in_us/TIME_OUT_MULTIPLIER_16;
462 		if (timeout_in_us % TIME_OUT_MULTIPLIER_16 != 0)
463 			length++;
464 	} else if (timeout_in_us <= 4 * TIME_OUT_INCREMENT) {
465 		multiplier = 2;
466 		length = timeout_in_us/TIME_OUT_MULTIPLIER_32;
467 		if (timeout_in_us % TIME_OUT_MULTIPLIER_32 != 0)
468 			length++;
469 	} else if (timeout_in_us > 4 * TIME_OUT_INCREMENT) {
470 		multiplier = 3;
471 		length = timeout_in_us/TIME_OUT_MULTIPLIER_64;
472 		if (timeout_in_us % TIME_OUT_MULTIPLIER_64 != 0)
473 			length++;
474 	}
475 
476 	length = (length < MAX_TIMEOUT_LENGTH) ? length : MAX_TIMEOUT_LENGTH;
477 
478 	REG_GET_2(AUX_DPHY_RX_CONTROL1, AUX_RX_TIMEOUT_LEN, &prev_length, AUX_RX_TIMEOUT_LEN_MUL, &prev_mult);
479 
480 	switch (prev_mult) {
481 	case 0:
482 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_8;
483 		break;
484 	case 1:
485 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_16;
486 		break;
487 	case 2:
488 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_32;
489 		break;
490 	case 3:
491 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_64;
492 		break;
493 	default:
494 		prev_timeout_val = DEFAULT_AUX_ENGINE_LENGTH * TIME_OUT_MULTIPLIER_8;
495 		break;
496 	}
497 
498 	REG_UPDATE_SEQ_2(AUX_DPHY_RX_CONTROL1, AUX_RX_TIMEOUT_LEN, length, AUX_RX_TIMEOUT_LEN_MUL, multiplier);
499 
500 	return prev_timeout_val;
501 }
502 
503 static struct dce_aux_funcs aux_functions = {
504 	.configure_timeout = NULL,
505 	.destroy = NULL,
506 };
507 
508 struct dce_aux *dce110_aux_engine_construct(struct aux_engine_dce110 *aux_engine110,
509 		struct dc_context *ctx,
510 		uint32_t inst,
511 		uint32_t timeout_period,
512 		const struct dce110_aux_registers *regs,
513 		const struct dce110_aux_registers_mask *mask,
514 		const struct dce110_aux_registers_shift *shift,
515 		bool is_ext_aux_timeout_configurable)
516 {
517 	aux_engine110->base.ddc = NULL;
518 	aux_engine110->base.ctx = ctx;
519 	aux_engine110->base.delay = 0;
520 	aux_engine110->base.max_defer_write_retry = 0;
521 	aux_engine110->base.inst = inst;
522 	aux_engine110->polling_timeout_period = timeout_period;
523 	aux_engine110->regs = regs;
524 
525 	aux_engine110->mask = mask;
526 	aux_engine110->shift = shift;
527 	aux_engine110->base.funcs = &aux_functions;
528 	if (is_ext_aux_timeout_configurable)
529 		aux_engine110->base.funcs->configure_timeout = &dce_aux_configure_timeout;
530 
531 	return &aux_engine110->base;
532 }
533 
534 static enum i2caux_transaction_action i2caux_action_from_payload(struct aux_payload *payload)
535 {
536 	if (payload->i2c_over_aux) {
537 		if (payload->write_status_update) {
538 			if (payload->mot)
539 				return I2CAUX_TRANSACTION_ACTION_I2C_STATUS_REQUEST_MOT;
540 			else
541 				return I2CAUX_TRANSACTION_ACTION_I2C_STATUS_REQUEST;
542 		}
543 		if (payload->write) {
544 			if (payload->mot)
545 				return I2CAUX_TRANSACTION_ACTION_I2C_WRITE_MOT;
546 			else
547 				return I2CAUX_TRANSACTION_ACTION_I2C_WRITE;
548 		}
549 		if (payload->mot)
550 			return I2CAUX_TRANSACTION_ACTION_I2C_READ_MOT;
551 
552 		return I2CAUX_TRANSACTION_ACTION_I2C_READ;
553 	}
554 	if (payload->write)
555 		return I2CAUX_TRANSACTION_ACTION_DP_WRITE;
556 
557 	return I2CAUX_TRANSACTION_ACTION_DP_READ;
558 }
559 
560 int dce_aux_transfer_raw(struct ddc_service *ddc,
561 		struct aux_payload *payload,
562 		enum aux_return_code_type *operation_result)
563 {
564 	struct ddc *ddc_pin = ddc->ddc_pin;
565 	struct dce_aux *aux_engine;
566 	struct aux_request_transaction_data aux_req;
567 	struct aux_reply_transaction_data aux_rep;
568 	uint8_t returned_bytes = 0;
569 	int res = -1;
570 	uint32_t status;
571 
572 	memset(&aux_req, 0, sizeof(aux_req));
573 	memset(&aux_rep, 0, sizeof(aux_rep));
574 
575 	aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
576 	if (!acquire(aux_engine, ddc_pin)) {
577 		*operation_result = AUX_RET_ERROR_ENGINE_ACQUIRE;
578 		return -1;
579 	}
580 
581 	if (payload->i2c_over_aux)
582 		aux_req.type = AUX_TRANSACTION_TYPE_I2C;
583 	else
584 		aux_req.type = AUX_TRANSACTION_TYPE_DP;
585 
586 	aux_req.action = i2caux_action_from_payload(payload);
587 
588 	aux_req.address = payload->address;
589 	aux_req.delay = 0;
590 	aux_req.length = payload->length;
591 	aux_req.data = payload->data;
592 
593 	submit_channel_request(aux_engine, &aux_req);
594 	*operation_result = get_channel_status(aux_engine, &returned_bytes);
595 
596 	if (*operation_result == AUX_RET_SUCCESS) {
597 		int __maybe_unused bytes_replied = 0;
598 
599 		bytes_replied = read_channel_reply(aux_engine, payload->length,
600 					 payload->data, payload->reply,
601 					 &status);
602 		EVENT_LOG_AUX_REP(aux_engine->ddc->pin_data->en,
603 					EVENT_LOG_AUX_ORIGIN_NATIVE, *payload->reply,
604 					bytes_replied, payload->data);
605 		res = returned_bytes;
606 	} else {
607 		res = -1;
608 	}
609 
610 	release_engine(aux_engine);
611 	return res;
612 }
613 
614 int dce_aux_transfer_dmub_raw(struct ddc_service *ddc,
615 		struct aux_payload *payload,
616 		enum aux_return_code_type *operation_result)
617 {
618 	struct ddc *ddc_pin = ddc->ddc_pin;
619 
620 	if (ddc_pin != NULL) {
621 		struct dce_aux *aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
622 		/* XXX: Workaround to configure ddc channels for aux transactions */
623 		if (!acquire(aux_engine, ddc_pin)) {
624 			*operation_result = AUX_RET_ERROR_ENGINE_ACQUIRE;
625 			return -1;
626 		}
627 		release_engine(aux_engine);
628 	}
629 
630 	return dm_helper_dmub_aux_transfer_sync(ddc->ctx, ddc->link, payload, operation_result);
631 }
632 
633 #define AUX_MAX_RETRIES 7
634 #define AUX_MIN_DEFER_RETRIES 7
635 #define AUX_MAX_DEFER_TIMEOUT_MS 50
636 #define AUX_MAX_I2C_DEFER_RETRIES 7
637 #define AUX_MAX_INVALID_REPLY_RETRIES 2
638 #define AUX_MAX_TIMEOUT_RETRIES 3
639 #define AUX_DEFER_DELAY_FOR_DPIA 4 /*ms*/
640 
641 static void dce_aux_log_payload(const char *payload_name,
642 	unsigned char *payload, uint32_t length, uint32_t max_length_to_log)
643 {
644 	if (!IS_DC_I2CAUX_LOGGING_ENABLED())
645 		return;
646 
647 	if (payload && length) {
648 		char hex_str[128] = {0};
649 		char *hex_str_ptr = &hex_str[0];
650 		uint32_t hex_str_remaining = sizeof(hex_str);
651 		unsigned char *payload_ptr = payload;
652 		unsigned char *payload_max_to_log_ptr = payload_ptr + min(max_length_to_log, length);
653 		unsigned int count;
654 		char *padding = "";
655 
656 		while (payload_ptr < payload_max_to_log_ptr) {
657 			count = snprintf_count(hex_str_ptr, hex_str_remaining, "%s%02X", padding, *payload_ptr);
658 			padding = " ";
659 			hex_str_remaining -= count;
660 			hex_str_ptr += count;
661 			payload_ptr++;
662 		}
663 
664 		count = snprintf_count(hex_str_ptr, hex_str_remaining, "   ");
665 		hex_str_remaining -= count;
666 		hex_str_ptr += count;
667 
668 		payload_ptr = payload;
669 		while (payload_ptr < payload_max_to_log_ptr) {
670 			count = snprintf_count(hex_str_ptr, hex_str_remaining, "%c",
671 				*payload_ptr >= ' ' ? *payload_ptr : '.');
672 			hex_str_remaining -= count;
673 			hex_str_ptr += count;
674 			payload_ptr++;
675 		}
676 
677 		DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_VERBOSE,
678 					LOG_FLAG_I2cAux_DceAux,
679 					"dce_aux_log_payload: %s: length=%u: data: %s%s",
680 					payload_name,
681 					length,
682 					hex_str,
683 					(length > max_length_to_log ? " (...)" : " "));
684 	} else {
685 		DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_VERBOSE,
686 					LOG_FLAG_I2cAux_DceAux,
687 					"dce_aux_log_payload: %s: length=%u: data: <empty payload>",
688 					payload_name,
689 					length);
690 	}
691 }
692 
693 bool dce_aux_transfer_with_retries(struct ddc_service *ddc,
694 		struct aux_payload *payload)
695 {
696 	int i, ret = 0;
697 	uint8_t reply;
698 	bool payload_reply = true;
699 	enum aux_return_code_type operation_result;
700 	bool retry_on_defer = false;
701 	struct ddc *ddc_pin = ddc->ddc_pin;
702 	struct dce_aux *aux_engine = NULL;
703 	struct aux_engine_dce110 *aux110 = NULL;
704 	uint32_t defer_time_in_ms = 0;
705 
706 	int aux_ack_retries = 0,
707 		aux_defer_retries = 0,
708 		aux_i2c_defer_retries = 0,
709 		aux_timeout_retries = 0,
710 		aux_invalid_reply_retries = 0,
711 		aux_ack_m_retries = 0;
712 
713 	if (ddc_pin) {
714 		aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
715 		aux110 = FROM_AUX_ENGINE(aux_engine);
716 	}
717 
718 	if (!payload->reply) {
719 		payload_reply = false;
720 		payload->reply = &reply;
721 	}
722 
723 	for (i = 0; i < AUX_MAX_RETRIES; i++) {
724 		DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
725 					LOG_FLAG_I2cAux_DceAux,
726 					"dce_aux_transfer_with_retries: link_index=%u: START: retry %d of %d: address=0x%04x length=%u write=%d mot=%d",
727 					ddc && ddc->link ? ddc->link->link_index : UINT_MAX,
728 					i + 1,
729 					(int)AUX_MAX_RETRIES,
730 					payload->address,
731 					payload->length,
732 					(unsigned int) payload->write,
733 					(unsigned int) payload->mot);
734 		if (payload->write)
735 			dce_aux_log_payload("  write", payload->data, payload->length, 16);
736 		ret = dce_aux_transfer_raw(ddc, payload, &operation_result);
737 		DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
738 					LOG_FLAG_I2cAux_DceAux,
739 					"dce_aux_transfer_with_retries: link_index=%u: END: retry %d of %d: address=0x%04x length=%u write=%d mot=%d: ret=%d operation_result=%d payload->reply=%u",
740 					ddc && ddc->link ? ddc->link->link_index : UINT_MAX,
741 					i + 1,
742 					(int)AUX_MAX_RETRIES,
743 					payload->address,
744 					payload->length,
745 					(unsigned int) payload->write,
746 					(unsigned int) payload->mot,
747 					ret,
748 					(int)operation_result,
749 					(unsigned int) *payload->reply);
750 		if (!payload->write)
751 			dce_aux_log_payload("  read", payload->data, ret > 0 ? ret : 0, 16);
752 
753 		switch (operation_result) {
754 		case AUX_RET_SUCCESS:
755 			aux_timeout_retries = 0;
756 			aux_invalid_reply_retries = 0;
757 
758 			switch (*payload->reply) {
759 			case AUX_TRANSACTION_REPLY_AUX_ACK:
760 				DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
761 							LOG_FLAG_I2cAux_DceAux,
762 							"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: AUX_TRANSACTION_REPLY_AUX_ACK");
763 				if (!payload->write && payload->length != ret) {
764 					if (++aux_ack_retries >= AUX_MAX_RETRIES) {
765 						DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
766 									LOG_FLAG_Error_I2cAux,
767 									"dce_aux_transfer_with_retries: FAILURE: aux_ack_retries=%d >= AUX_MAX_RETRIES=%d",
768 									aux_defer_retries,
769 									AUX_MAX_RETRIES);
770 						goto fail;
771 					} else
772 						udelay(300);
773 				} else if (payload->write && ret > 0) {
774 					/* sink requested more time to complete the write via AUX_ACKM */
775 					if (++aux_ack_m_retries >= AUX_MAX_RETRIES) {
776 						DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
777 								LOG_FLAG_Error_I2cAux,
778 								"dce_aux_transfer_with_retries: FAILURE: aux_ack_m_retries=%d >= AUX_MAX_RETRIES=%d",
779 								aux_ack_m_retries,
780 								AUX_MAX_RETRIES);
781 						goto fail;
782 					}
783 
784 					/* retry reading the write status until complete
785 					 * NOTE: payload is modified here
786 					 */
787 					payload->write = false;
788 					payload->write_status_update = true;
789 					payload->length = 0;
790 					udelay(300);
791 
792 				} else
793 					return true;
794 			break;
795 
796 			case AUX_TRANSACTION_REPLY_AUX_DEFER:
797 				DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
798 							LOG_FLAG_I2cAux_DceAux,
799 							"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: AUX_TRANSACTION_REPLY_AUX_DEFER");
800 
801 				/* polling_timeout_period is in us */
802 				if (aux110)
803 					defer_time_in_ms += aux110->polling_timeout_period / 1000;
804 				else
805 					defer_time_in_ms += AUX_DEFER_DELAY_FOR_DPIA;
806 				++aux_defer_retries;
807 				fallthrough;
808 			case AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER:
809 				if (*payload->reply == AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER)
810 					DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
811 								LOG_FLAG_I2cAux_DceAux,
812 								"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER");
813 
814 				retry_on_defer = true;
815 				fallthrough;
816 			case AUX_TRANSACTION_REPLY_I2C_OVER_AUX_NACK:
817 				if (*payload->reply == AUX_TRANSACTION_REPLY_I2C_OVER_AUX_NACK)
818 					DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
819 								LOG_FLAG_I2cAux_DceAux,
820 								"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: AUX_TRANSACTION_REPLY_I2C_OVER_AUX_NACK");
821 
822 				if (aux_defer_retries >= AUX_MIN_DEFER_RETRIES
823 						&& defer_time_in_ms >= AUX_MAX_DEFER_TIMEOUT_MS) {
824 					DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
825 								LOG_FLAG_Error_I2cAux,
826 								"dce_aux_transfer_with_retries: FAILURE: aux_defer_retries=%d >= AUX_MIN_DEFER_RETRIES=%d && defer_time_in_ms=%d >= AUX_MAX_DEFER_TIMEOUT_MS=%d",
827 								aux_defer_retries,
828 								AUX_MIN_DEFER_RETRIES,
829 								defer_time_in_ms,
830 								AUX_MAX_DEFER_TIMEOUT_MS);
831 					goto fail;
832 				} else {
833 					if ((*payload->reply == AUX_TRANSACTION_REPLY_AUX_DEFER) ||
834 						(*payload->reply == AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER)) {
835 						DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
836 									LOG_FLAG_I2cAux_DceAux,
837 									"dce_aux_transfer_with_retries: payload->defer_delay=%u",
838 									payload->defer_delay);
839 						if (payload->defer_delay > 1) {
840 							msleep(payload->defer_delay);
841 							defer_time_in_ms += payload->defer_delay;
842 						} else if (payload->defer_delay <= 1) {
843 							udelay(payload->defer_delay * 1000);
844 							defer_time_in_ms += payload->defer_delay;
845 						}
846 					}
847 				}
848 				break;
849 
850 			case AUX_TRANSACTION_REPLY_I2C_DEFER:
851 				DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
852 							LOG_FLAG_I2cAux_DceAux,
853 							"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: AUX_TRANSACTION_REPLY_I2C_DEFER");
854 
855 				aux_defer_retries = 0;
856 				if (++aux_i2c_defer_retries >= AUX_MAX_I2C_DEFER_RETRIES) {
857 					DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
858 								LOG_FLAG_Error_I2cAux,
859 								"dce_aux_transfer_with_retries: FAILURE: aux_i2c_defer_retries=%d >= AUX_MAX_I2C_DEFER_RETRIES=%d",
860 								aux_i2c_defer_retries,
861 								AUX_MAX_I2C_DEFER_RETRIES);
862 					goto fail;
863 				}
864 				break;
865 
866 			case AUX_TRANSACTION_REPLY_AUX_NACK:
867 				DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
868 							LOG_FLAG_I2cAux_DceAux,
869 							"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: AUX_TRANSACTION_REPLY_AUX_NACK");
870 				goto fail;
871 
872 			case AUX_TRANSACTION_REPLY_HPD_DISCON:
873 				DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
874 							LOG_FLAG_I2cAux_DceAux,
875 							"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: AUX_TRANSACTION_REPLY_HPD_DISCON");
876 				goto fail;
877 
878 			default:
879 				DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
880 							LOG_FLAG_Error_I2cAux,
881 							"dce_aux_transfer_with_retries: AUX_RET_SUCCESS: FAILURE: AUX_TRANSACTION_REPLY_* unknown, default case.");
882 				goto fail;
883 			}
884 			break;
885 
886 		case AUX_RET_ERROR_INVALID_REPLY:
887 			DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
888 						LOG_FLAG_I2cAux_DceAux,
889 						"dce_aux_transfer_with_retries: AUX_RET_ERROR_INVALID_REPLY");
890 			if (++aux_invalid_reply_retries >= AUX_MAX_INVALID_REPLY_RETRIES) {
891 				DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
892 							LOG_FLAG_Error_I2cAux,
893 							"dce_aux_transfer_with_retries: FAILURE: aux_invalid_reply_retries=%d >= AUX_MAX_INVALID_REPLY_RETRIES=%d",
894 							aux_invalid_reply_retries,
895 							AUX_MAX_INVALID_REPLY_RETRIES);
896 				goto fail;
897 			} else
898 				udelay(400);
899 			break;
900 
901 		case AUX_RET_ERROR_TIMEOUT:
902 			DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
903 						LOG_FLAG_I2cAux_DceAux,
904 						"dce_aux_transfer_with_retries: AUX_RET_ERROR_TIMEOUT");
905 			// Check whether a DEFER had occurred before the timeout.
906 			// If so, treat timeout as a DEFER.
907 			if (retry_on_defer) {
908 				if (++aux_defer_retries >= AUX_MIN_DEFER_RETRIES) {
909 					DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
910 								LOG_FLAG_Error_I2cAux,
911 								"dce_aux_transfer_with_retries: FAILURE: aux_defer_retries=%d >= AUX_MIN_DEFER_RETRIES=%d",
912 								aux_defer_retries,
913 								AUX_MIN_DEFER_RETRIES);
914 					goto fail;
915 				} else if (payload->defer_delay > 0) {
916 					DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
917 								LOG_FLAG_I2cAux_DceAux,
918 								"dce_aux_transfer_with_retries: payload->defer_delay=%u",
919 								payload->defer_delay);
920 					msleep(payload->defer_delay);
921 				}
922 			} else {
923 				if (++aux_timeout_retries >= AUX_MAX_TIMEOUT_RETRIES) {
924 					DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
925 								LOG_FLAG_Error_I2cAux,
926 								"dce_aux_transfer_with_retries: FAILURE: aux_timeout_retries=%d >= AUX_MAX_TIMEOUT_RETRIES=%d",
927 								aux_timeout_retries,
928 								AUX_MAX_TIMEOUT_RETRIES);
929 					goto fail;
930 				} else {
931 					/*
932 					 * DP 1.4, 2.8.2:  AUX Transaction Response/Reply Timeouts
933 					 * According to the DP spec there should be 3 retries total
934 					 * with a 400us wait inbetween each. Hardware already waits
935 					 * for 550us therefore no wait is required here.
936 					 */
937 				}
938 			}
939 			break;
940 
941 		case AUX_RET_ERROR_HPD_DISCON:
942 		case AUX_RET_ERROR_ENGINE_ACQUIRE:
943 		case AUX_RET_ERROR_UNKNOWN:
944 		default:
945 			DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
946 						LOG_FLAG_I2cAux_DceAux,
947 						"dce_aux_transfer_with_retries: Failure: operation_result=%d",
948 						(int)operation_result);
949 			goto fail;
950 		}
951 	}
952 
953 fail:
954 	DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
955 				LOG_FLAG_Error_I2cAux,
956 				"dce_aux_transfer_with_retries: FAILURE");
957 	if (!payload_reply)
958 		payload->reply = NULL;
959 
960 	DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_ERROR,
961 				WPP_BIT_FLAG_DC_ERROR,
962 				"AUX transaction failed. Result: %d",
963 				operation_result);
964 
965 	return false;
966 }
967