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 #include "reg_helper.h"
46 
47 #undef FN
48 #define FN(reg_name, field_name) \
49 	aux110->shift->field_name, aux110->mask->field_name
50 
51 #define FROM_AUX_ENGINE(ptr) \
52 	container_of((ptr), struct aux_engine_dce110, base)
53 
54 #define FROM_ENGINE(ptr) \
55 	FROM_AUX_ENGINE(container_of((ptr), struct dce_aux, base))
56 
57 #define FROM_AUX_ENGINE_ENGINE(ptr) \
58 	container_of((ptr), struct dce_aux, base)
59 enum {
60 	AUX_INVALID_REPLY_RETRY_COUNTER = 1,
61 	AUX_TIMED_OUT_RETRY_COUNTER = 2,
62 	AUX_DEFER_RETRY_COUNTER = 6
63 };
64 
65 #define TIME_OUT_INCREMENT        1016
66 #define TIME_OUT_MULTIPLIER_8     8
67 #define TIME_OUT_MULTIPLIER_16    16
68 #define TIME_OUT_MULTIPLIER_32    32
69 #define TIME_OUT_MULTIPLIER_64    64
70 #define MAX_TIMEOUT_LENGTH        127
71 #define DEFAULT_AUX_ENGINE_MULT   0
72 #define DEFAULT_AUX_ENGINE_LENGTH 69
73 
74 static void release_engine(
75 	struct dce_aux *engine)
76 {
77 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
78 
79 	dal_ddc_close(engine->ddc);
80 
81 	engine->ddc = NULL;
82 
83 	REG_UPDATE(AUX_ARB_CONTROL, AUX_SW_DONE_USING_AUX_REG, 1);
84 }
85 
86 #define SW_CAN_ACCESS_AUX 1
87 #define DMCU_CAN_ACCESS_AUX 2
88 
89 static bool is_engine_available(
90 	struct dce_aux *engine)
91 {
92 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
93 
94 	uint32_t value = REG_READ(AUX_ARB_CONTROL);
95 	uint32_t field = get_reg_field_value(
96 			value,
97 			AUX_ARB_CONTROL,
98 			AUX_REG_RW_CNTL_STATUS);
99 
100 	return (field != DMCU_CAN_ACCESS_AUX);
101 }
102 static bool acquire_engine(
103 	struct dce_aux *engine)
104 {
105 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
106 
107 	uint32_t value = REG_READ(AUX_ARB_CONTROL);
108 	uint32_t field = get_reg_field_value(
109 			value,
110 			AUX_ARB_CONTROL,
111 			AUX_REG_RW_CNTL_STATUS);
112 	if (field == DMCU_CAN_ACCESS_AUX)
113 		return false;
114 	/* enable AUX before request SW to access AUX */
115 	value = REG_READ(AUX_CONTROL);
116 	field = get_reg_field_value(value,
117 				AUX_CONTROL,
118 				AUX_EN);
119 
120 	if (field == 0) {
121 		set_reg_field_value(
122 				value,
123 				1,
124 				AUX_CONTROL,
125 				AUX_EN);
126 
127 		if (REG(AUX_RESET_MASK)) {
128 			/*DP_AUX block as part of the enable sequence*/
129 			set_reg_field_value(
130 				value,
131 				1,
132 				AUX_CONTROL,
133 				AUX_RESET);
134 		}
135 
136 		REG_WRITE(AUX_CONTROL, value);
137 
138 		if (REG(AUX_RESET_MASK)) {
139 			/*poll HW to make sure reset it done*/
140 
141 			REG_WAIT(AUX_CONTROL, AUX_RESET_DONE, 1,
142 					1, 11);
143 
144 			set_reg_field_value(
145 				value,
146 				0,
147 				AUX_CONTROL,
148 				AUX_RESET);
149 
150 			REG_WRITE(AUX_CONTROL, value);
151 
152 			REG_WAIT(AUX_CONTROL, AUX_RESET_DONE, 0,
153 					1, 11);
154 		}
155 	} /*if (field)*/
156 
157 	/* request SW to access AUX */
158 	REG_UPDATE(AUX_ARB_CONTROL, AUX_SW_USE_AUX_REG_REQ, 1);
159 
160 	value = REG_READ(AUX_ARB_CONTROL);
161 	field = get_reg_field_value(
162 			value,
163 			AUX_ARB_CONTROL,
164 			AUX_REG_RW_CNTL_STATUS);
165 
166 	return (field == SW_CAN_ACCESS_AUX);
167 }
168 
169 #define COMPOSE_AUX_SW_DATA_16_20(command, address) \
170 	((command) | ((0xF0000 & (address)) >> 16))
171 
172 #define COMPOSE_AUX_SW_DATA_8_15(address) \
173 	((0xFF00 & (address)) >> 8)
174 
175 #define COMPOSE_AUX_SW_DATA_0_7(address) \
176 	(0xFF & (address))
177 
178 static void submit_channel_request(
179 	struct dce_aux *engine,
180 	struct aux_request_transaction_data *request)
181 {
182 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
183 	uint32_t value;
184 	uint32_t length;
185 
186 	bool is_write =
187 		((request->type == AUX_TRANSACTION_TYPE_DP) &&
188 		 (request->action == I2CAUX_TRANSACTION_ACTION_DP_WRITE)) ||
189 		((request->type == AUX_TRANSACTION_TYPE_I2C) &&
190 		((request->action == I2CAUX_TRANSACTION_ACTION_I2C_WRITE) ||
191 		 (request->action == I2CAUX_TRANSACTION_ACTION_I2C_WRITE_MOT)));
192 	if (REG(AUXN_IMPCAL)) {
193 		/* clear_aux_error */
194 		REG_UPDATE_SEQ_2(AUXN_IMPCAL,
195 				AUXN_CALOUT_ERROR_AK, 1,
196 				AUXN_CALOUT_ERROR_AK, 0);
197 
198 		REG_UPDATE_SEQ_2(AUXP_IMPCAL,
199 				AUXP_CALOUT_ERROR_AK, 1,
200 				AUXP_CALOUT_ERROR_AK, 0);
201 
202 		/* force_default_calibrate */
203 		REG_UPDATE_SEQ_2(AUXN_IMPCAL,
204 				AUXN_IMPCAL_ENABLE, 1,
205 				AUXN_IMPCAL_OVERRIDE_ENABLE, 0);
206 
207 		/* bug? why AUXN update EN and OVERRIDE_EN 1 by 1 while AUX P toggles OVERRIDE? */
208 
209 		REG_UPDATE_SEQ_2(AUXP_IMPCAL,
210 				AUXP_IMPCAL_OVERRIDE_ENABLE, 1,
211 				AUXP_IMPCAL_OVERRIDE_ENABLE, 0);
212 	}
213 
214 	REG_UPDATE(AUX_INTERRUPT_CONTROL, AUX_SW_DONE_ACK, 1);
215 
216 	REG_WAIT(AUX_SW_STATUS, AUX_SW_DONE, 0,
217 				10, aux110->polling_timeout_period/10);
218 
219 	/* set the delay and the number of bytes to write */
220 
221 	/* The length include
222 	 * the 4 bit header and the 20 bit address
223 	 * (that is 3 byte).
224 	 * If the requested length is non zero this means
225 	 * an addition byte specifying the length is required.
226 	 */
227 
228 	length = request->length ? 4 : 3;
229 	if (is_write)
230 		length += request->length;
231 
232 	REG_UPDATE_2(AUX_SW_CONTROL,
233 			AUX_SW_START_DELAY, request->delay,
234 			AUX_SW_WR_BYTES, length);
235 
236 	/* program action and address and payload data (if 'is_write') */
237 	value = REG_UPDATE_4(AUX_SW_DATA,
238 			AUX_SW_INDEX, 0,
239 			AUX_SW_DATA_RW, 0,
240 			AUX_SW_AUTOINCREMENT_DISABLE, 1,
241 			AUX_SW_DATA, COMPOSE_AUX_SW_DATA_16_20(request->action, request->address));
242 
243 	value = REG_SET_2(AUX_SW_DATA, value,
244 			AUX_SW_AUTOINCREMENT_DISABLE, 0,
245 			AUX_SW_DATA, COMPOSE_AUX_SW_DATA_8_15(request->address));
246 
247 	value = REG_SET(AUX_SW_DATA, value,
248 			AUX_SW_DATA, COMPOSE_AUX_SW_DATA_0_7(request->address));
249 
250 	if (request->length) {
251 		value = REG_SET(AUX_SW_DATA, value,
252 				AUX_SW_DATA, request->length - 1);
253 	}
254 
255 	if (is_write) {
256 		/* Load the HW buffer with the Data to be sent.
257 		 * This is relevant for write operation.
258 		 * For read, the data recived data will be
259 		 * processed in process_channel_reply().
260 		 */
261 		uint32_t i = 0;
262 
263 		while (i < request->length) {
264 			value = REG_SET(AUX_SW_DATA, value,
265 					AUX_SW_DATA, request->data[i]);
266 
267 			++i;
268 		}
269 	}
270 
271 	REG_UPDATE(AUX_SW_CONTROL, AUX_SW_GO, 1);
272 	EVENT_LOG_AUX_REQ(engine->ddc->pin_data->en, EVENT_LOG_AUX_ORIGIN_NATIVE,
273 					request->action, request->address, request->length, request->data);
274 }
275 
276 static int read_channel_reply(struct dce_aux *engine, uint32_t size,
277 			      uint8_t *buffer, uint8_t *reply_result,
278 			      uint32_t *sw_status)
279 {
280 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
281 	uint32_t bytes_replied;
282 	uint32_t reply_result_32;
283 
284 	*sw_status = REG_GET(AUX_SW_STATUS, AUX_SW_REPLY_BYTE_COUNT,
285 			     &bytes_replied);
286 
287 	/* In case HPD is LOW, exit AUX transaction */
288 	if ((*sw_status & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK))
289 		return -1;
290 
291 	/* Need at least the status byte */
292 	if (!bytes_replied)
293 		return -1;
294 
295 	REG_UPDATE_SEQ_3(AUX_SW_DATA,
296 			  AUX_SW_INDEX, 0,
297 			  AUX_SW_AUTOINCREMENT_DISABLE, 1,
298 			  AUX_SW_DATA_RW, 1);
299 
300 	REG_GET(AUX_SW_DATA, AUX_SW_DATA, &reply_result_32);
301 	reply_result_32 = reply_result_32 >> 4;
302 	if (reply_result != NULL)
303 		*reply_result = (uint8_t)reply_result_32;
304 
305 	if (reply_result_32 == 0) { /* ACK */
306 		uint32_t i = 0;
307 
308 		/* First byte was already used to get the command status */
309 		--bytes_replied;
310 
311 		/* Do not overflow buffer */
312 		if (bytes_replied > size)
313 			return -1;
314 
315 		while (i < bytes_replied) {
316 			uint32_t aux_sw_data_val;
317 
318 			REG_GET(AUX_SW_DATA, AUX_SW_DATA, &aux_sw_data_val);
319 			buffer[i] = aux_sw_data_val;
320 			++i;
321 		}
322 
323 		return i;
324 	}
325 
326 	return 0;
327 }
328 
329 static enum aux_return_code_type get_channel_status(
330 	struct dce_aux *engine,
331 	uint8_t *returned_bytes)
332 {
333 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine);
334 
335 	uint32_t value;
336 
337 	if (returned_bytes == NULL) {
338 		/*caller pass NULL pointer*/
339 		ASSERT_CRITICAL(false);
340 		return AUX_RET_ERROR_UNKNOWN;
341 	}
342 	*returned_bytes = 0;
343 
344 	/* poll to make sure that SW_DONE is asserted */
345 	REG_WAIT(AUX_SW_STATUS, AUX_SW_DONE, 1,
346 				10, aux110->polling_timeout_period/10);
347 
348 	value = REG_READ(AUX_SW_STATUS);
349 	/* in case HPD is LOW, exit AUX transaction */
350 	if ((value & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK))
351 		return AUX_RET_ERROR_HPD_DISCON;
352 
353 	/* Note that the following bits are set in 'status.bits'
354 	 * during CTS 4.2.1.2 (FW 3.3.1):
355 	 * AUX_SW_RX_MIN_COUNT_VIOL, AUX_SW_RX_INVALID_STOP,
356 	 * AUX_SW_RX_RECV_NO_DET, AUX_SW_RX_RECV_INVALID_H.
357 	 *
358 	 * AUX_SW_RX_MIN_COUNT_VIOL is an internal,
359 	 * HW debugging bit and should be ignored.
360 	 */
361 	if (value & AUX_SW_STATUS__AUX_SW_DONE_MASK) {
362 		if ((value & AUX_SW_STATUS__AUX_SW_RX_TIMEOUT_STATE_MASK) ||
363 			(value & AUX_SW_STATUS__AUX_SW_RX_TIMEOUT_MASK))
364 			return AUX_RET_ERROR_TIMEOUT;
365 
366 		else if ((value & AUX_SW_STATUS__AUX_SW_RX_INVALID_STOP_MASK) ||
367 			(value & AUX_SW_STATUS__AUX_SW_RX_RECV_NO_DET_MASK) ||
368 			(value &
369 				AUX_SW_STATUS__AUX_SW_RX_RECV_INVALID_H_MASK) ||
370 			(value & AUX_SW_STATUS__AUX_SW_RX_RECV_INVALID_L_MASK))
371 			return AUX_RET_ERROR_INVALID_REPLY;
372 
373 		*returned_bytes = get_reg_field_value(value,
374 				AUX_SW_STATUS,
375 				AUX_SW_REPLY_BYTE_COUNT);
376 
377 		if (*returned_bytes == 0)
378 			return
379 			AUX_RET_ERROR_INVALID_REPLY;
380 		else {
381 			*returned_bytes -= 1;
382 			return AUX_RET_SUCCESS;
383 		}
384 	} else {
385 		/*time_elapsed >= aux_engine->timeout_period
386 		 *  AUX_SW_STATUS__AUX_SW_HPD_DISCON = at this point
387 		 */
388 		ASSERT_CRITICAL(false);
389 		return AUX_RET_ERROR_TIMEOUT;
390 	}
391 }
392 
393 static bool acquire(
394 	struct dce_aux *engine,
395 	struct ddc *ddc)
396 {
397 	enum gpio_result result;
398 
399 	if ((engine == NULL) || !is_engine_available(engine))
400 		return false;
401 
402 	result = dal_ddc_open(ddc, GPIO_MODE_HARDWARE,
403 		GPIO_DDC_CONFIG_TYPE_MODE_AUX);
404 
405 	if (result != GPIO_RESULT_OK)
406 		return false;
407 
408 	if (!acquire_engine(engine)) {
409 		dal_ddc_close(ddc);
410 		return false;
411 	}
412 
413 	engine->ddc = ddc;
414 
415 	return true;
416 }
417 
418 void dce110_engine_destroy(struct dce_aux **engine)
419 {
420 
421 	struct aux_engine_dce110 *engine110 = FROM_AUX_ENGINE(*engine);
422 
423 	kfree(engine110);
424 	*engine = NULL;
425 
426 }
427 
428 static uint32_t dce_aux_configure_timeout(struct ddc_service *ddc,
429 		uint32_t timeout_in_us)
430 {
431 	uint32_t multiplier = 0;
432 	uint32_t length = 0;
433 	uint32_t prev_length = 0;
434 	uint32_t prev_mult = 0;
435 	uint32_t prev_timeout_val = 0;
436 	struct ddc *ddc_pin = ddc->ddc_pin;
437 	struct dce_aux *aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
438 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(aux_engine);
439 
440 	/* 1-Update polling timeout period */
441 	aux110->polling_timeout_period = timeout_in_us * SW_AUX_TIMEOUT_PERIOD_MULTIPLIER;
442 
443 	/* 2-Update aux timeout period length and multiplier */
444 	if (timeout_in_us == 0) {
445 		multiplier = DEFAULT_AUX_ENGINE_MULT;
446 		length = DEFAULT_AUX_ENGINE_LENGTH;
447 	} else if (timeout_in_us <= TIME_OUT_INCREMENT) {
448 		multiplier = 0;
449 		length = timeout_in_us/TIME_OUT_MULTIPLIER_8;
450 		if (timeout_in_us % TIME_OUT_MULTIPLIER_8 != 0)
451 			length++;
452 	} else if (timeout_in_us <= 2 * TIME_OUT_INCREMENT) {
453 		multiplier = 1;
454 		length = timeout_in_us/TIME_OUT_MULTIPLIER_16;
455 		if (timeout_in_us % TIME_OUT_MULTIPLIER_16 != 0)
456 			length++;
457 	} else if (timeout_in_us <= 4 * TIME_OUT_INCREMENT) {
458 		multiplier = 2;
459 		length = timeout_in_us/TIME_OUT_MULTIPLIER_32;
460 		if (timeout_in_us % TIME_OUT_MULTIPLIER_32 != 0)
461 			length++;
462 	} else if (timeout_in_us > 4 * TIME_OUT_INCREMENT) {
463 		multiplier = 3;
464 		length = timeout_in_us/TIME_OUT_MULTIPLIER_64;
465 		if (timeout_in_us % TIME_OUT_MULTIPLIER_64 != 0)
466 			length++;
467 	}
468 
469 	length = (length < MAX_TIMEOUT_LENGTH) ? length : MAX_TIMEOUT_LENGTH;
470 
471 	REG_GET_2(AUX_DPHY_RX_CONTROL1, AUX_RX_TIMEOUT_LEN, &prev_length, AUX_RX_TIMEOUT_LEN_MUL, &prev_mult);
472 
473 	switch (prev_mult) {
474 	case 0:
475 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_8;
476 		break;
477 	case 1:
478 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_16;
479 		break;
480 	case 2:
481 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_32;
482 		break;
483 	case 3:
484 		prev_timeout_val = prev_length * TIME_OUT_MULTIPLIER_64;
485 		break;
486 	default:
487 		prev_timeout_val = DEFAULT_AUX_ENGINE_LENGTH * TIME_OUT_MULTIPLIER_8;
488 		break;
489 	}
490 
491 	REG_UPDATE_SEQ_2(AUX_DPHY_RX_CONTROL1, AUX_RX_TIMEOUT_LEN, length, AUX_RX_TIMEOUT_LEN_MUL, multiplier);
492 
493 	return prev_timeout_val;
494 }
495 
496 static struct dce_aux_funcs aux_functions = {
497 	.configure_timeout = NULL,
498 	.destroy = NULL,
499 };
500 
501 struct dce_aux *dce110_aux_engine_construct(struct aux_engine_dce110 *aux_engine110,
502 		struct dc_context *ctx,
503 		uint32_t inst,
504 		uint32_t timeout_period,
505 		const struct dce110_aux_registers *regs,
506 		const struct dce110_aux_registers_mask *mask,
507 		const struct dce110_aux_registers_shift *shift,
508 		bool is_ext_aux_timeout_configurable)
509 {
510 	aux_engine110->base.ddc = NULL;
511 	aux_engine110->base.ctx = ctx;
512 	aux_engine110->base.delay = 0;
513 	aux_engine110->base.max_defer_write_retry = 0;
514 	aux_engine110->base.inst = inst;
515 	aux_engine110->polling_timeout_period = timeout_period;
516 	aux_engine110->regs = regs;
517 
518 	aux_engine110->mask = mask;
519 	aux_engine110->shift = shift;
520 	aux_engine110->base.funcs = &aux_functions;
521 	if (is_ext_aux_timeout_configurable)
522 		aux_engine110->base.funcs->configure_timeout = &dce_aux_configure_timeout;
523 
524 	return &aux_engine110->base;
525 }
526 
527 static enum i2caux_transaction_action i2caux_action_from_payload(struct aux_payload *payload)
528 {
529 	if (payload->i2c_over_aux) {
530 		if (payload->write) {
531 			if (payload->mot)
532 				return I2CAUX_TRANSACTION_ACTION_I2C_WRITE_MOT;
533 			return I2CAUX_TRANSACTION_ACTION_I2C_WRITE;
534 		}
535 		if (payload->mot)
536 			return I2CAUX_TRANSACTION_ACTION_I2C_READ_MOT;
537 		return I2CAUX_TRANSACTION_ACTION_I2C_READ;
538 	}
539 	if (payload->write)
540 		return I2CAUX_TRANSACTION_ACTION_DP_WRITE;
541 	return I2CAUX_TRANSACTION_ACTION_DP_READ;
542 }
543 
544 int dce_aux_transfer_raw(struct ddc_service *ddc,
545 		struct aux_payload *payload,
546 		enum aux_return_code_type *operation_result)
547 {
548 	struct ddc *ddc_pin = ddc->ddc_pin;
549 	struct dce_aux *aux_engine;
550 	struct aux_request_transaction_data aux_req;
551 	struct aux_reply_transaction_data aux_rep;
552 	uint8_t returned_bytes = 0;
553 	int res = -1;
554 	uint32_t status;
555 
556 	memset(&aux_req, 0, sizeof(aux_req));
557 	memset(&aux_rep, 0, sizeof(aux_rep));
558 
559 	aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
560 	if (!acquire(aux_engine, ddc_pin)) {
561 		*operation_result = AUX_RET_ERROR_ENGINE_ACQUIRE;
562 		return -1;
563 	}
564 
565 	if (payload->i2c_over_aux)
566 		aux_req.type = AUX_TRANSACTION_TYPE_I2C;
567 	else
568 		aux_req.type = AUX_TRANSACTION_TYPE_DP;
569 
570 	aux_req.action = i2caux_action_from_payload(payload);
571 
572 	aux_req.address = payload->address;
573 	aux_req.delay = 0;
574 	aux_req.length = payload->length;
575 	aux_req.data = payload->data;
576 
577 	submit_channel_request(aux_engine, &aux_req);
578 	*operation_result = get_channel_status(aux_engine, &returned_bytes);
579 
580 	if (*operation_result == AUX_RET_SUCCESS) {
581 		int __maybe_unused bytes_replied = 0;
582 
583 		bytes_replied = read_channel_reply(aux_engine, payload->length,
584 					 payload->data, payload->reply,
585 					 &status);
586 		EVENT_LOG_AUX_REP(aux_engine->ddc->pin_data->en,
587 					EVENT_LOG_AUX_ORIGIN_NATIVE, *payload->reply,
588 					bytes_replied, payload->data);
589 		res = returned_bytes;
590 	} else {
591 		res = -1;
592 	}
593 
594 	release_engine(aux_engine);
595 	return res;
596 }
597 
598 int dce_aux_transfer_dmub_raw(struct ddc_service *ddc,
599 		struct aux_payload *payload,
600 		enum aux_return_code_type *operation_result)
601 {
602 	struct ddc *ddc_pin = ddc->ddc_pin;
603 
604 	if (ddc_pin != NULL) {
605 		struct dce_aux *aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
606 		/* XXX: Workaround to configure ddc channels for aux transactions */
607 		if (!acquire(aux_engine, ddc_pin)) {
608 			*operation_result = AUX_RET_ERROR_ENGINE_ACQUIRE;
609 			return -1;
610 		}
611 		release_engine(aux_engine);
612 	}
613 
614 	return dm_helper_dmub_aux_transfer_sync(ddc->ctx, ddc->link, payload, operation_result);
615 }
616 
617 #define AUX_MAX_RETRIES 7
618 #define AUX_MIN_DEFER_RETRIES 7
619 #define AUX_MAX_DEFER_TIMEOUT_MS 50
620 #define AUX_MAX_I2C_DEFER_RETRIES 7
621 #define AUX_MAX_INVALID_REPLY_RETRIES 2
622 #define AUX_MAX_TIMEOUT_RETRIES 3
623 
624 bool dce_aux_transfer_with_retries(struct ddc_service *ddc,
625 		struct aux_payload *payload)
626 {
627 	int i, ret = 0;
628 	uint8_t reply;
629 	bool payload_reply = true;
630 	enum aux_return_code_type operation_result;
631 	bool retry_on_defer = false;
632 	struct ddc *ddc_pin = ddc->ddc_pin;
633 	struct dce_aux *aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
634 	struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(aux_engine);
635 	uint32_t defer_time_in_ms = 0;
636 
637 	int aux_ack_retries = 0,
638 		aux_defer_retries = 0,
639 		aux_i2c_defer_retries = 0,
640 		aux_timeout_retries = 0,
641 		aux_invalid_reply_retries = 0;
642 
643 	if (!payload->reply) {
644 		payload_reply = false;
645 		payload->reply = &reply;
646 	}
647 
648 	for (i = 0; i < AUX_MAX_RETRIES; i++) {
649 		ret = dce_aux_transfer_raw(ddc, payload, &operation_result);
650 
651 		switch (operation_result) {
652 		case AUX_RET_SUCCESS:
653 			aux_timeout_retries = 0;
654 			aux_invalid_reply_retries = 0;
655 
656 			switch (*payload->reply) {
657 			case AUX_TRANSACTION_REPLY_AUX_ACK:
658 				if (!payload->write && payload->length != ret) {
659 					if (++aux_ack_retries >= AUX_MAX_RETRIES)
660 						goto fail;
661 					else
662 						udelay(300);
663 				} else
664 					return true;
665 			break;
666 
667 			case AUX_TRANSACTION_REPLY_AUX_DEFER:
668 				/* polling_timeout_period is in us */
669 				defer_time_in_ms += aux110->polling_timeout_period / 1000;
670 				++aux_defer_retries;
671 				fallthrough;
672 			case AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER:
673 				retry_on_defer = true;
674 				fallthrough;
675 			case AUX_TRANSACTION_REPLY_I2C_OVER_AUX_NACK:
676 				if (aux_defer_retries >= AUX_MIN_DEFER_RETRIES
677 						&& defer_time_in_ms >= AUX_MAX_DEFER_TIMEOUT_MS) {
678 					goto fail;
679 				} else {
680 					if ((*payload->reply == AUX_TRANSACTION_REPLY_AUX_DEFER) ||
681 						(*payload->reply == AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER)) {
682 						if (payload->defer_delay > 1) {
683 							msleep(payload->defer_delay);
684 							defer_time_in_ms += payload->defer_delay;
685 						} else if (payload->defer_delay <= 1) {
686 							udelay(payload->defer_delay * 1000);
687 							defer_time_in_ms += payload->defer_delay;
688 						}
689 					}
690 				}
691 				break;
692 
693 			case AUX_TRANSACTION_REPLY_I2C_DEFER:
694 				aux_defer_retries = 0;
695 				if (++aux_i2c_defer_retries >= AUX_MAX_I2C_DEFER_RETRIES)
696 					goto fail;
697 				break;
698 
699 			case AUX_TRANSACTION_REPLY_AUX_NACK:
700 			case AUX_TRANSACTION_REPLY_HPD_DISCON:
701 			default:
702 				goto fail;
703 			}
704 			break;
705 
706 		case AUX_RET_ERROR_INVALID_REPLY:
707 			if (++aux_invalid_reply_retries >= AUX_MAX_INVALID_REPLY_RETRIES)
708 				goto fail;
709 			else
710 				udelay(400);
711 			break;
712 
713 		case AUX_RET_ERROR_TIMEOUT:
714 			// Check whether a DEFER had occurred before the timeout.
715 			// If so, treat timeout as a DEFER.
716 			if (retry_on_defer) {
717 				if (++aux_defer_retries >= AUX_MIN_DEFER_RETRIES)
718 					goto fail;
719 				else if (payload->defer_delay > 0)
720 					msleep(payload->defer_delay);
721 			} else {
722 				if (++aux_timeout_retries >= AUX_MAX_TIMEOUT_RETRIES)
723 					goto fail;
724 				else {
725 					/*
726 					 * DP 1.4, 2.8.2:  AUX Transaction Response/Reply Timeouts
727 					 * According to the DP spec there should be 3 retries total
728 					 * with a 400us wait inbetween each. Hardware already waits
729 					 * for 550us therefore no wait is required here.
730 					 */
731 				}
732 			}
733 			break;
734 
735 		case AUX_RET_ERROR_HPD_DISCON:
736 		case AUX_RET_ERROR_ENGINE_ACQUIRE:
737 		case AUX_RET_ERROR_UNKNOWN:
738 		default:
739 			goto fail;
740 		}
741 	}
742 
743 fail:
744 	if (!payload_reply)
745 		payload->reply = NULL;
746 	return false;
747 }
748