xref: /openbmc/linux/drivers/misc/mei/hw-txe.c (revision 9cfc5c90)
1 /*
2  *
3  * Intel Management Engine Interface (Intel MEI) Linux driver
4  * Copyright (c) 2013-2014, Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13  * more details.
14  *
15  */
16 
17 #include <linux/pci.h>
18 #include <linux/jiffies.h>
19 #include <linux/ktime.h>
20 #include <linux/delay.h>
21 #include <linux/kthread.h>
22 #include <linux/irqreturn.h>
23 
24 #include <linux/mei.h>
25 
26 #include "mei_dev.h"
27 #include "hw-txe.h"
28 #include "client.h"
29 #include "hbm.h"
30 
31 /**
32  * mei_txe_reg_read - Reads 32bit data from the txe device
33  *
34  * @base_addr: registers base address
35  * @offset: register offset
36  *
37  * Return: register value
38  */
39 static inline u32 mei_txe_reg_read(void __iomem *base_addr,
40 					unsigned long offset)
41 {
42 	return ioread32(base_addr + offset);
43 }
44 
45 /**
46  * mei_txe_reg_write - Writes 32bit data to the txe device
47  *
48  * @base_addr: registers base address
49  * @offset: register offset
50  * @value: the value to write
51  */
52 static inline void mei_txe_reg_write(void __iomem *base_addr,
53 				unsigned long offset, u32 value)
54 {
55 	iowrite32(value, base_addr + offset);
56 }
57 
58 /**
59  * mei_txe_sec_reg_read_silent - Reads 32bit data from the SeC BAR
60  *
61  * @hw: the txe hardware structure
62  * @offset: register offset
63  *
64  * Doesn't check for aliveness while Reads 32bit data from the SeC BAR
65  *
66  * Return: register value
67  */
68 static inline u32 mei_txe_sec_reg_read_silent(struct mei_txe_hw *hw,
69 				unsigned long offset)
70 {
71 	return mei_txe_reg_read(hw->mem_addr[SEC_BAR], offset);
72 }
73 
74 /**
75  * mei_txe_sec_reg_read - Reads 32bit data from the SeC BAR
76  *
77  * @hw: the txe hardware structure
78  * @offset: register offset
79  *
80  * Reads 32bit data from the SeC BAR and shout loud if aliveness is not set
81  *
82  * Return: register value
83  */
84 static inline u32 mei_txe_sec_reg_read(struct mei_txe_hw *hw,
85 				unsigned long offset)
86 {
87 	WARN(!hw->aliveness, "sec read: aliveness not asserted\n");
88 	return mei_txe_sec_reg_read_silent(hw, offset);
89 }
90 /**
91  * mei_txe_sec_reg_write_silent - Writes 32bit data to the SeC BAR
92  *   doesn't check for aliveness
93  *
94  * @hw: the txe hardware structure
95  * @offset: register offset
96  * @value: value to write
97  *
98  * Doesn't check for aliveness while writes 32bit data from to the SeC BAR
99  */
100 static inline void mei_txe_sec_reg_write_silent(struct mei_txe_hw *hw,
101 				unsigned long offset, u32 value)
102 {
103 	mei_txe_reg_write(hw->mem_addr[SEC_BAR], offset, value);
104 }
105 
106 /**
107  * mei_txe_sec_reg_write - Writes 32bit data to the SeC BAR
108  *
109  * @hw: the txe hardware structure
110  * @offset: register offset
111  * @value: value to write
112  *
113  * Writes 32bit data from the SeC BAR and shout loud if aliveness is not set
114  */
115 static inline void mei_txe_sec_reg_write(struct mei_txe_hw *hw,
116 				unsigned long offset, u32 value)
117 {
118 	WARN(!hw->aliveness, "sec write: aliveness not asserted\n");
119 	mei_txe_sec_reg_write_silent(hw, offset, value);
120 }
121 /**
122  * mei_txe_br_reg_read - Reads 32bit data from the Bridge BAR
123  *
124  * @hw: the txe hardware structure
125  * @offset: offset from which to read the data
126  *
127  * Return: the byte read.
128  */
129 static inline u32 mei_txe_br_reg_read(struct mei_txe_hw *hw,
130 				unsigned long offset)
131 {
132 	return mei_txe_reg_read(hw->mem_addr[BRIDGE_BAR], offset);
133 }
134 
135 /**
136  * mei_txe_br_reg_write - Writes 32bit data to the Bridge BAR
137  *
138  * @hw: the txe hardware structure
139  * @offset: offset from which to write the data
140  * @value: the byte to write
141  */
142 static inline void mei_txe_br_reg_write(struct mei_txe_hw *hw,
143 				unsigned long offset, u32 value)
144 {
145 	mei_txe_reg_write(hw->mem_addr[BRIDGE_BAR], offset, value);
146 }
147 
148 /**
149  * mei_txe_aliveness_set - request for aliveness change
150  *
151  * @dev: the device structure
152  * @req: requested aliveness value
153  *
154  * Request for aliveness change and returns true if the change is
155  *   really needed and false if aliveness is already
156  *   in the requested state
157  *
158  * Locking: called under "dev->device_lock" lock
159  *
160  * Return: true if request was send
161  */
162 static bool mei_txe_aliveness_set(struct mei_device *dev, u32 req)
163 {
164 
165 	struct mei_txe_hw *hw = to_txe_hw(dev);
166 	bool do_req = hw->aliveness != req;
167 
168 	dev_dbg(dev->dev, "Aliveness current=%d request=%d\n",
169 				hw->aliveness, req);
170 	if (do_req) {
171 		dev->pg_event = MEI_PG_EVENT_WAIT;
172 		mei_txe_br_reg_write(hw, SICR_HOST_ALIVENESS_REQ_REG, req);
173 	}
174 	return do_req;
175 }
176 
177 
178 /**
179  * mei_txe_aliveness_req_get - get aliveness requested register value
180  *
181  * @dev: the device structure
182  *
183  * Extract HICR_HOST_ALIVENESS_RESP_ACK bit from
184  * from HICR_HOST_ALIVENESS_REQ register value
185  *
186  * Return: SICR_HOST_ALIVENESS_REQ_REQUESTED bit value
187  */
188 static u32 mei_txe_aliveness_req_get(struct mei_device *dev)
189 {
190 	struct mei_txe_hw *hw = to_txe_hw(dev);
191 	u32 reg;
192 
193 	reg = mei_txe_br_reg_read(hw, SICR_HOST_ALIVENESS_REQ_REG);
194 	return reg & SICR_HOST_ALIVENESS_REQ_REQUESTED;
195 }
196 
197 /**
198  * mei_txe_aliveness_get - get aliveness response register value
199  *
200  * @dev: the device structure
201  *
202  * Return: HICR_HOST_ALIVENESS_RESP_ACK bit from HICR_HOST_ALIVENESS_RESP
203  *         register
204  */
205 static u32 mei_txe_aliveness_get(struct mei_device *dev)
206 {
207 	struct mei_txe_hw *hw = to_txe_hw(dev);
208 	u32 reg;
209 
210 	reg = mei_txe_br_reg_read(hw, HICR_HOST_ALIVENESS_RESP_REG);
211 	return reg & HICR_HOST_ALIVENESS_RESP_ACK;
212 }
213 
214 /**
215  * mei_txe_aliveness_poll - waits for aliveness to settle
216  *
217  * @dev: the device structure
218  * @expected: expected aliveness value
219  *
220  * Polls for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
221  *
222  * Return: 0 if the expected value was received, -ETIME otherwise
223  */
224 static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
225 {
226 	struct mei_txe_hw *hw = to_txe_hw(dev);
227 	ktime_t stop, start;
228 
229 	start = ktime_get();
230 	stop = ktime_add(start, ms_to_ktime(SEC_ALIVENESS_WAIT_TIMEOUT));
231 	do {
232 		hw->aliveness = mei_txe_aliveness_get(dev);
233 		if (hw->aliveness == expected) {
234 			dev->pg_event = MEI_PG_EVENT_IDLE;
235 			dev_dbg(dev->dev, "aliveness settled after %lld usecs\n",
236 				ktime_to_us(ktime_sub(ktime_get(), start)));
237 			return 0;
238 		}
239 		usleep_range(20, 50);
240 	} while (ktime_before(ktime_get(), stop));
241 
242 	dev->pg_event = MEI_PG_EVENT_IDLE;
243 	dev_err(dev->dev, "aliveness timed out\n");
244 	return -ETIME;
245 }
246 
247 /**
248  * mei_txe_aliveness_wait - waits for aliveness to settle
249  *
250  * @dev: the device structure
251  * @expected: expected aliveness value
252  *
253  * Waits for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
254  *
255  * Return: 0 on success and < 0 otherwise
256  */
257 static int mei_txe_aliveness_wait(struct mei_device *dev, u32 expected)
258 {
259 	struct mei_txe_hw *hw = to_txe_hw(dev);
260 	const unsigned long timeout =
261 			msecs_to_jiffies(SEC_ALIVENESS_WAIT_TIMEOUT);
262 	long err;
263 	int ret;
264 
265 	hw->aliveness = mei_txe_aliveness_get(dev);
266 	if (hw->aliveness == expected)
267 		return 0;
268 
269 	mutex_unlock(&dev->device_lock);
270 	err = wait_event_timeout(hw->wait_aliveness_resp,
271 			dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
272 	mutex_lock(&dev->device_lock);
273 
274 	hw->aliveness = mei_txe_aliveness_get(dev);
275 	ret = hw->aliveness == expected ? 0 : -ETIME;
276 
277 	if (ret)
278 		dev_warn(dev->dev, "aliveness timed out = %ld aliveness = %d event = %d\n",
279 			err, hw->aliveness, dev->pg_event);
280 	else
281 		dev_dbg(dev->dev, "aliveness settled after = %d msec aliveness = %d event = %d\n",
282 			jiffies_to_msecs(timeout - err),
283 			hw->aliveness, dev->pg_event);
284 
285 	dev->pg_event = MEI_PG_EVENT_IDLE;
286 	return ret;
287 }
288 
289 /**
290  * mei_txe_aliveness_set_sync - sets an wait for aliveness to complete
291  *
292  * @dev: the device structure
293  * @req: requested aliveness value
294  *
295  * Return: 0 on success and < 0 otherwise
296  */
297 int mei_txe_aliveness_set_sync(struct mei_device *dev, u32 req)
298 {
299 	if (mei_txe_aliveness_set(dev, req))
300 		return mei_txe_aliveness_wait(dev, req);
301 	return 0;
302 }
303 
304 /**
305  * mei_txe_pg_in_transition - is device now in pg transition
306  *
307  * @dev: the device structure
308  *
309  * Return: true if in pg transition, false otherwise
310  */
311 static bool mei_txe_pg_in_transition(struct mei_device *dev)
312 {
313 	return dev->pg_event == MEI_PG_EVENT_WAIT;
314 }
315 
316 /**
317  * mei_txe_pg_is_enabled - detect if PG is supported by HW
318  *
319  * @dev: the device structure
320  *
321  * Return: true is pg supported, false otherwise
322  */
323 static bool mei_txe_pg_is_enabled(struct mei_device *dev)
324 {
325 	return true;
326 }
327 
328 /**
329  * mei_txe_pg_state  - translate aliveness register value
330  *   to the mei power gating state
331  *
332  * @dev: the device structure
333  *
334  * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
335  */
336 static inline enum mei_pg_state mei_txe_pg_state(struct mei_device *dev)
337 {
338 	struct mei_txe_hw *hw = to_txe_hw(dev);
339 
340 	return hw->aliveness ? MEI_PG_OFF : MEI_PG_ON;
341 }
342 
343 /**
344  * mei_txe_input_ready_interrupt_enable - sets the Input Ready Interrupt
345  *
346  * @dev: the device structure
347  */
348 static void mei_txe_input_ready_interrupt_enable(struct mei_device *dev)
349 {
350 	struct mei_txe_hw *hw = to_txe_hw(dev);
351 	u32 hintmsk;
352 	/* Enable the SEC_IPC_HOST_INT_MASK_IN_RDY interrupt */
353 	hintmsk = mei_txe_sec_reg_read(hw, SEC_IPC_HOST_INT_MASK_REG);
354 	hintmsk |= SEC_IPC_HOST_INT_MASK_IN_RDY;
355 	mei_txe_sec_reg_write(hw, SEC_IPC_HOST_INT_MASK_REG, hintmsk);
356 }
357 
358 /**
359  * mei_txe_input_doorbell_set - sets bit 0 in
360  *    SEC_IPC_INPUT_DOORBELL.IPC_INPUT_DOORBELL.
361  *
362  * @hw: the txe hardware structure
363  */
364 static void mei_txe_input_doorbell_set(struct mei_txe_hw *hw)
365 {
366 	/* Clear the interrupt cause */
367 	clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause);
368 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_DOORBELL_REG, 1);
369 }
370 
371 /**
372  * mei_txe_output_ready_set - Sets the SICR_SEC_IPC_OUTPUT_STATUS bit to 1
373  *
374  * @hw: the txe hardware structure
375  */
376 static void mei_txe_output_ready_set(struct mei_txe_hw *hw)
377 {
378 	mei_txe_br_reg_write(hw,
379 			SICR_SEC_IPC_OUTPUT_STATUS_REG,
380 			SEC_IPC_OUTPUT_STATUS_RDY);
381 }
382 
383 /**
384  * mei_txe_is_input_ready - check if TXE is ready for receiving data
385  *
386  * @dev: the device structure
387  *
388  * Return: true if INPUT STATUS READY bit is set
389  */
390 static bool mei_txe_is_input_ready(struct mei_device *dev)
391 {
392 	struct mei_txe_hw *hw = to_txe_hw(dev);
393 	u32 status;
394 
395 	status = mei_txe_sec_reg_read(hw, SEC_IPC_INPUT_STATUS_REG);
396 	return !!(SEC_IPC_INPUT_STATUS_RDY & status);
397 }
398 
399 /**
400  * mei_txe_intr_clear - clear all interrupts
401  *
402  * @dev: the device structure
403  */
404 static inline void mei_txe_intr_clear(struct mei_device *dev)
405 {
406 	struct mei_txe_hw *hw = to_txe_hw(dev);
407 
408 	mei_txe_sec_reg_write_silent(hw, SEC_IPC_HOST_INT_STATUS_REG,
409 		SEC_IPC_HOST_INT_STATUS_PENDING);
410 	mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_STS_MSK);
411 	mei_txe_br_reg_write(hw, HHISR_REG, IPC_HHIER_MSK);
412 }
413 
414 /**
415  * mei_txe_intr_disable - disable all interrupts
416  *
417  * @dev: the device structure
418  */
419 static void mei_txe_intr_disable(struct mei_device *dev)
420 {
421 	struct mei_txe_hw *hw = to_txe_hw(dev);
422 
423 	mei_txe_br_reg_write(hw, HHIER_REG, 0);
424 	mei_txe_br_reg_write(hw, HIER_REG, 0);
425 }
426 /**
427  * mei_txe_intr_enable - enable all interrupts
428  *
429  * @dev: the device structure
430  */
431 static void mei_txe_intr_enable(struct mei_device *dev)
432 {
433 	struct mei_txe_hw *hw = to_txe_hw(dev);
434 
435 	mei_txe_br_reg_write(hw, HHIER_REG, IPC_HHIER_MSK);
436 	mei_txe_br_reg_write(hw, HIER_REG, HIER_INT_EN_MSK);
437 }
438 
439 /**
440  * mei_txe_pending_interrupts - check if there are pending interrupts
441  *	only Aliveness, Input ready, and output doorbell are of relevance
442  *
443  * @dev: the device structure
444  *
445  * Checks if there are pending interrupts
446  * only Aliveness, Readiness, Input ready, and Output doorbell are relevant
447  *
448  * Return: true if there are pending interrupts
449  */
450 static bool mei_txe_pending_interrupts(struct mei_device *dev)
451 {
452 
453 	struct mei_txe_hw *hw = to_txe_hw(dev);
454 	bool ret = (hw->intr_cause & (TXE_INTR_READINESS |
455 				      TXE_INTR_ALIVENESS |
456 				      TXE_INTR_IN_READY  |
457 				      TXE_INTR_OUT_DB));
458 
459 	if (ret) {
460 		dev_dbg(dev->dev,
461 			"Pending Interrupts InReady=%01d Readiness=%01d, Aliveness=%01d, OutDoor=%01d\n",
462 			!!(hw->intr_cause & TXE_INTR_IN_READY),
463 			!!(hw->intr_cause & TXE_INTR_READINESS),
464 			!!(hw->intr_cause & TXE_INTR_ALIVENESS),
465 			!!(hw->intr_cause & TXE_INTR_OUT_DB));
466 	}
467 	return ret;
468 }
469 
470 /**
471  * mei_txe_input_payload_write - write a dword to the host buffer
472  *	at offset idx
473  *
474  * @dev: the device structure
475  * @idx: index in the host buffer
476  * @value: value
477  */
478 static void mei_txe_input_payload_write(struct mei_device *dev,
479 			unsigned long idx, u32 value)
480 {
481 	struct mei_txe_hw *hw = to_txe_hw(dev);
482 
483 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_PAYLOAD_REG +
484 			(idx * sizeof(u32)), value);
485 }
486 
487 /**
488  * mei_txe_out_data_read - read dword from the device buffer
489  *	at offset idx
490  *
491  * @dev: the device structure
492  * @idx: index in the device buffer
493  *
494  * Return: register value at index
495  */
496 static u32 mei_txe_out_data_read(const struct mei_device *dev,
497 					unsigned long idx)
498 {
499 	struct mei_txe_hw *hw = to_txe_hw(dev);
500 
501 	return mei_txe_br_reg_read(hw,
502 		BRIDGE_IPC_OUTPUT_PAYLOAD_REG + (idx * sizeof(u32)));
503 }
504 
505 /* Readiness */
506 
507 /**
508  * mei_txe_readiness_set_host_rdy - set host readiness bit
509  *
510  * @dev: the device structure
511  */
512 static void mei_txe_readiness_set_host_rdy(struct mei_device *dev)
513 {
514 	struct mei_txe_hw *hw = to_txe_hw(dev);
515 
516 	mei_txe_br_reg_write(hw,
517 		SICR_HOST_IPC_READINESS_REQ_REG,
518 		SICR_HOST_IPC_READINESS_HOST_RDY);
519 }
520 
521 /**
522  * mei_txe_readiness_clear - clear host readiness bit
523  *
524  * @dev: the device structure
525  */
526 static void mei_txe_readiness_clear(struct mei_device *dev)
527 {
528 	struct mei_txe_hw *hw = to_txe_hw(dev);
529 
530 	mei_txe_br_reg_write(hw, SICR_HOST_IPC_READINESS_REQ_REG,
531 				SICR_HOST_IPC_READINESS_RDY_CLR);
532 }
533 /**
534  * mei_txe_readiness_get - Reads and returns
535  *	the HICR_SEC_IPC_READINESS register value
536  *
537  * @dev: the device structure
538  *
539  * Return: the HICR_SEC_IPC_READINESS register value
540  */
541 static u32 mei_txe_readiness_get(struct mei_device *dev)
542 {
543 	struct mei_txe_hw *hw = to_txe_hw(dev);
544 
545 	return mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
546 }
547 
548 
549 /**
550  * mei_txe_readiness_is_sec_rdy - check readiness
551  *  for HICR_SEC_IPC_READINESS_SEC_RDY
552  *
553  * @readiness: cached readiness state
554  *
555  * Return: true if readiness bit is set
556  */
557 static inline bool mei_txe_readiness_is_sec_rdy(u32 readiness)
558 {
559 	return !!(readiness & HICR_SEC_IPC_READINESS_SEC_RDY);
560 }
561 
562 /**
563  * mei_txe_hw_is_ready - check if the hw is ready
564  *
565  * @dev: the device structure
566  *
567  * Return: true if sec is ready
568  */
569 static bool mei_txe_hw_is_ready(struct mei_device *dev)
570 {
571 	u32 readiness =  mei_txe_readiness_get(dev);
572 
573 	return mei_txe_readiness_is_sec_rdy(readiness);
574 }
575 
576 /**
577  * mei_txe_host_is_ready - check if the host is ready
578  *
579  * @dev: the device structure
580  *
581  * Return: true if host is ready
582  */
583 static inline bool mei_txe_host_is_ready(struct mei_device *dev)
584 {
585 	struct mei_txe_hw *hw = to_txe_hw(dev);
586 	u32 reg = mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
587 
588 	return !!(reg & HICR_SEC_IPC_READINESS_HOST_RDY);
589 }
590 
591 /**
592  * mei_txe_readiness_wait - wait till readiness settles
593  *
594  * @dev: the device structure
595  *
596  * Return: 0 on success and -ETIME on timeout
597  */
598 static int mei_txe_readiness_wait(struct mei_device *dev)
599 {
600 	if (mei_txe_hw_is_ready(dev))
601 		return 0;
602 
603 	mutex_unlock(&dev->device_lock);
604 	wait_event_timeout(dev->wait_hw_ready, dev->recvd_hw_ready,
605 			msecs_to_jiffies(SEC_RESET_WAIT_TIMEOUT));
606 	mutex_lock(&dev->device_lock);
607 	if (!dev->recvd_hw_ready) {
608 		dev_err(dev->dev, "wait for readiness failed\n");
609 		return -ETIME;
610 	}
611 
612 	dev->recvd_hw_ready = false;
613 	return 0;
614 }
615 
616 static const struct mei_fw_status mei_txe_fw_sts = {
617 	.count = 2,
618 	.status[0] = PCI_CFG_TXE_FW_STS0,
619 	.status[1] = PCI_CFG_TXE_FW_STS1
620 };
621 
622 /**
623  * mei_txe_fw_status - read fw status register from pci config space
624  *
625  * @dev: mei device
626  * @fw_status: fw status register values
627  *
628  * Return: 0 on success, error otherwise
629  */
630 static int mei_txe_fw_status(struct mei_device *dev,
631 			     struct mei_fw_status *fw_status)
632 {
633 	const struct mei_fw_status *fw_src = &mei_txe_fw_sts;
634 	struct pci_dev *pdev = to_pci_dev(dev->dev);
635 	int ret;
636 	int i;
637 
638 	if (!fw_status)
639 		return -EINVAL;
640 
641 	fw_status->count = fw_src->count;
642 	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
643 		ret = pci_read_config_dword(pdev,
644 			fw_src->status[i], &fw_status->status[i]);
645 		if (ret)
646 			return ret;
647 	}
648 
649 	return 0;
650 }
651 
652 /**
653  *  mei_txe_hw_config - configure hardware at the start of the devices
654  *
655  * @dev: the device structure
656  *
657  * Configure hardware at the start of the device should be done only
658  *   once at the device probe time
659  */
660 static void mei_txe_hw_config(struct mei_device *dev)
661 {
662 
663 	struct mei_txe_hw *hw = to_txe_hw(dev);
664 
665 	/* Doesn't change in runtime */
666 	dev->hbuf_depth = PAYLOAD_SIZE / 4;
667 
668 	hw->aliveness = mei_txe_aliveness_get(dev);
669 	hw->readiness = mei_txe_readiness_get(dev);
670 
671 	dev_dbg(dev->dev, "aliveness_resp = 0x%08x, readiness = 0x%08x.\n",
672 		hw->aliveness, hw->readiness);
673 }
674 
675 
676 /**
677  * mei_txe_write - writes a message to device.
678  *
679  * @dev: the device structure
680  * @header: header of message
681  * @buf: message buffer will be written
682  *
683  * Return: 0 if success, <0 - otherwise.
684  */
685 
686 static int mei_txe_write(struct mei_device *dev,
687 		struct mei_msg_hdr *header, unsigned char *buf)
688 {
689 	struct mei_txe_hw *hw = to_txe_hw(dev);
690 	unsigned long rem;
691 	unsigned long length;
692 	int slots = dev->hbuf_depth;
693 	u32 *reg_buf = (u32 *)buf;
694 	u32 dw_cnt;
695 	int i;
696 
697 	if (WARN_ON(!header || !buf))
698 		return -EINVAL;
699 
700 	length = header->length;
701 
702 	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(header));
703 
704 	dw_cnt = mei_data2slots(length);
705 	if (dw_cnt > slots)
706 		return -EMSGSIZE;
707 
708 	if (WARN(!hw->aliveness, "txe write: aliveness not asserted\n"))
709 		return -EAGAIN;
710 
711 	/* Enable Input Ready Interrupt. */
712 	mei_txe_input_ready_interrupt_enable(dev);
713 
714 	if (!mei_txe_is_input_ready(dev)) {
715 		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
716 
717 		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
718 		dev_err(dev->dev, "Input is not ready %s\n", fw_sts_str);
719 		return -EAGAIN;
720 	}
721 
722 	mei_txe_input_payload_write(dev, 0, *((u32 *)header));
723 
724 	for (i = 0; i < length / 4; i++)
725 		mei_txe_input_payload_write(dev, i + 1, reg_buf[i]);
726 
727 	rem = length & 0x3;
728 	if (rem > 0) {
729 		u32 reg = 0;
730 
731 		memcpy(&reg, &buf[length - rem], rem);
732 		mei_txe_input_payload_write(dev, i + 1, reg);
733 	}
734 
735 	/* after each write the whole buffer is consumed */
736 	hw->slots = 0;
737 
738 	/* Set Input-Doorbell */
739 	mei_txe_input_doorbell_set(hw);
740 
741 	return 0;
742 }
743 
744 /**
745  * mei_txe_hbuf_max_len - mimics the me hbuf circular buffer
746  *
747  * @dev: the device structure
748  *
749  * Return: the PAYLOAD_SIZE - 4
750  */
751 static size_t mei_txe_hbuf_max_len(const struct mei_device *dev)
752 {
753 	return PAYLOAD_SIZE - sizeof(struct mei_msg_hdr);
754 }
755 
756 /**
757  * mei_txe_hbuf_empty_slots - mimics the me hbuf circular buffer
758  *
759  * @dev: the device structure
760  *
761  * Return: always hbuf_depth
762  */
763 static int mei_txe_hbuf_empty_slots(struct mei_device *dev)
764 {
765 	struct mei_txe_hw *hw = to_txe_hw(dev);
766 
767 	return hw->slots;
768 }
769 
770 /**
771  * mei_txe_count_full_read_slots - mimics the me device circular buffer
772  *
773  * @dev: the device structure
774  *
775  * Return: always buffer size in dwords count
776  */
777 static int mei_txe_count_full_read_slots(struct mei_device *dev)
778 {
779 	/* read buffers has static size */
780 	return  PAYLOAD_SIZE / 4;
781 }
782 
783 /**
784  * mei_txe_read_hdr - read message header which is always in 4 first bytes
785  *
786  * @dev: the device structure
787  *
788  * Return: mei message header
789  */
790 
791 static u32 mei_txe_read_hdr(const struct mei_device *dev)
792 {
793 	return mei_txe_out_data_read(dev, 0);
794 }
795 /**
796  * mei_txe_read - reads a message from the txe device.
797  *
798  * @dev: the device structure
799  * @buf: message buffer will be written
800  * @len: message size will be read
801  *
802  * Return: -EINVAL on error wrong argument and 0 on success
803  */
804 static int mei_txe_read(struct mei_device *dev,
805 		unsigned char *buf, unsigned long len)
806 {
807 
808 	struct mei_txe_hw *hw = to_txe_hw(dev);
809 	u32 *reg_buf, reg;
810 	u32 rem;
811 	u32 i;
812 
813 	if (WARN_ON(!buf || !len))
814 		return -EINVAL;
815 
816 	reg_buf = (u32 *)buf;
817 	rem = len & 0x3;
818 
819 	dev_dbg(dev->dev, "buffer-length = %lu buf[0]0x%08X\n",
820 		len, mei_txe_out_data_read(dev, 0));
821 
822 	for (i = 0; i < len / 4; i++) {
823 		/* skip header: index starts from 1 */
824 		reg = mei_txe_out_data_read(dev, i + 1);
825 		dev_dbg(dev->dev, "buf[%d] = 0x%08X\n", i, reg);
826 		*reg_buf++ = reg;
827 	}
828 
829 	if (rem) {
830 		reg = mei_txe_out_data_read(dev, i + 1);
831 		memcpy(reg_buf, &reg, rem);
832 	}
833 
834 	mei_txe_output_ready_set(hw);
835 	return 0;
836 }
837 
838 /**
839  * mei_txe_hw_reset - resets host and fw.
840  *
841  * @dev: the device structure
842  * @intr_enable: if interrupt should be enabled after reset.
843  *
844  * Return: 0 on success and < 0 in case of error
845  */
846 static int mei_txe_hw_reset(struct mei_device *dev, bool intr_enable)
847 {
848 	struct mei_txe_hw *hw = to_txe_hw(dev);
849 
850 	u32 aliveness_req;
851 	/*
852 	 * read input doorbell to ensure consistency between  Bridge and SeC
853 	 * return value might be garbage return
854 	 */
855 	(void)mei_txe_sec_reg_read_silent(hw, SEC_IPC_INPUT_DOORBELL_REG);
856 
857 	aliveness_req = mei_txe_aliveness_req_get(dev);
858 	hw->aliveness = mei_txe_aliveness_get(dev);
859 
860 	/* Disable interrupts in this stage we will poll */
861 	mei_txe_intr_disable(dev);
862 
863 	/*
864 	 * If Aliveness Request and Aliveness Response are not equal then
865 	 * wait for them to be equal
866 	 * Since we might have interrupts disabled - poll for it
867 	 */
868 	if (aliveness_req != hw->aliveness)
869 		if (mei_txe_aliveness_poll(dev, aliveness_req) < 0) {
870 			dev_err(dev->dev, "wait for aliveness settle failed ... bailing out\n");
871 			return -EIO;
872 		}
873 
874 	/*
875 	 * If Aliveness Request and Aliveness Response are set then clear them
876 	 */
877 	if (aliveness_req) {
878 		mei_txe_aliveness_set(dev, 0);
879 		if (mei_txe_aliveness_poll(dev, 0) < 0) {
880 			dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
881 			return -EIO;
882 		}
883 	}
884 
885 	/*
886 	 * Set readiness RDY_CLR bit
887 	 */
888 	mei_txe_readiness_clear(dev);
889 
890 	return 0;
891 }
892 
893 /**
894  * mei_txe_hw_start - start the hardware after reset
895  *
896  * @dev: the device structure
897  *
898  * Return: 0 on success an error code otherwise
899  */
900 static int mei_txe_hw_start(struct mei_device *dev)
901 {
902 	struct mei_txe_hw *hw = to_txe_hw(dev);
903 	int ret;
904 
905 	u32 hisr;
906 
907 	/* bring back interrupts */
908 	mei_txe_intr_enable(dev);
909 
910 	ret = mei_txe_readiness_wait(dev);
911 	if (ret < 0) {
912 		dev_err(dev->dev, "waiting for readiness failed\n");
913 		return ret;
914 	}
915 
916 	/*
917 	 * If HISR.INT2_STS interrupt status bit is set then clear it.
918 	 */
919 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
920 	if (hisr & HISR_INT_2_STS)
921 		mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_2_STS);
922 
923 	/* Clear the interrupt cause of OutputDoorbell */
924 	clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause);
925 
926 	ret = mei_txe_aliveness_set_sync(dev, 1);
927 	if (ret < 0) {
928 		dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
929 		return ret;
930 	}
931 
932 	/* enable input ready interrupts:
933 	 * SEC_IPC_HOST_INT_MASK.IPC_INPUT_READY_INT_MASK
934 	 */
935 	mei_txe_input_ready_interrupt_enable(dev);
936 
937 
938 	/*  Set the SICR_SEC_IPC_OUTPUT_STATUS.IPC_OUTPUT_READY bit */
939 	mei_txe_output_ready_set(hw);
940 
941 	/* Set bit SICR_HOST_IPC_READINESS.HOST_RDY
942 	 */
943 	mei_txe_readiness_set_host_rdy(dev);
944 
945 	return 0;
946 }
947 
948 /**
949  * mei_txe_check_and_ack_intrs - translate multi BAR interrupt into
950  *  single bit mask and acknowledge the interrupts
951  *
952  * @dev: the device structure
953  * @do_ack: acknowledge interrupts
954  *
955  * Return: true if found interrupts to process.
956  */
957 static bool mei_txe_check_and_ack_intrs(struct mei_device *dev, bool do_ack)
958 {
959 	struct mei_txe_hw *hw = to_txe_hw(dev);
960 	u32 hisr;
961 	u32 hhisr;
962 	u32 ipc_isr;
963 	u32 aliveness;
964 	bool generated;
965 
966 	/* read interrupt registers */
967 	hhisr = mei_txe_br_reg_read(hw, HHISR_REG);
968 	generated = (hhisr & IPC_HHIER_MSK);
969 	if (!generated)
970 		goto out;
971 
972 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
973 
974 	aliveness = mei_txe_aliveness_get(dev);
975 	if (hhisr & IPC_HHIER_SEC && aliveness)
976 		ipc_isr = mei_txe_sec_reg_read_silent(hw,
977 				SEC_IPC_HOST_INT_STATUS_REG);
978 	else
979 		ipc_isr = 0;
980 
981 	generated = generated ||
982 		(hisr & HISR_INT_STS_MSK) ||
983 		(ipc_isr & SEC_IPC_HOST_INT_STATUS_PENDING);
984 
985 	if (generated && do_ack) {
986 		/* Save the interrupt causes */
987 		hw->intr_cause |= hisr & HISR_INT_STS_MSK;
988 		if (ipc_isr & SEC_IPC_HOST_INT_STATUS_IN_RDY)
989 			hw->intr_cause |= TXE_INTR_IN_READY;
990 
991 
992 		mei_txe_intr_disable(dev);
993 		/* Clear the interrupts in hierarchy:
994 		 * IPC and Bridge, than the High Level */
995 		mei_txe_sec_reg_write_silent(hw,
996 			SEC_IPC_HOST_INT_STATUS_REG, ipc_isr);
997 		mei_txe_br_reg_write(hw, HISR_REG, hisr);
998 		mei_txe_br_reg_write(hw, HHISR_REG, hhisr);
999 	}
1000 
1001 out:
1002 	return generated;
1003 }
1004 
1005 /**
1006  * mei_txe_irq_quick_handler - The ISR of the MEI device
1007  *
1008  * @irq: The irq number
1009  * @dev_id: pointer to the device structure
1010  *
1011  * Return: IRQ_WAKE_THREAD if interrupt is designed for the device
1012  *         IRQ_NONE otherwise
1013  */
1014 irqreturn_t mei_txe_irq_quick_handler(int irq, void *dev_id)
1015 {
1016 	struct mei_device *dev = dev_id;
1017 
1018 	if (mei_txe_check_and_ack_intrs(dev, true))
1019 		return IRQ_WAKE_THREAD;
1020 	return IRQ_NONE;
1021 }
1022 
1023 
1024 /**
1025  * mei_txe_irq_thread_handler - txe interrupt thread
1026  *
1027  * @irq: The irq number
1028  * @dev_id: pointer to the device structure
1029  *
1030  * Return: IRQ_HANDLED
1031  */
1032 irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
1033 {
1034 	struct mei_device *dev = (struct mei_device *) dev_id;
1035 	struct mei_txe_hw *hw = to_txe_hw(dev);
1036 	struct mei_cl_cb complete_list;
1037 	s32 slots;
1038 	int rets = 0;
1039 
1040 	dev_dbg(dev->dev, "irq thread: Interrupt Registers HHISR|HISR|SEC=%02X|%04X|%02X\n",
1041 		mei_txe_br_reg_read(hw, HHISR_REG),
1042 		mei_txe_br_reg_read(hw, HISR_REG),
1043 		mei_txe_sec_reg_read_silent(hw, SEC_IPC_HOST_INT_STATUS_REG));
1044 
1045 
1046 	/* initialize our complete list */
1047 	mutex_lock(&dev->device_lock);
1048 	mei_io_list_init(&complete_list);
1049 
1050 	if (pci_dev_msi_enabled(to_pci_dev(dev->dev)))
1051 		mei_txe_check_and_ack_intrs(dev, true);
1052 
1053 	/* show irq events */
1054 	mei_txe_pending_interrupts(dev);
1055 
1056 	hw->aliveness = mei_txe_aliveness_get(dev);
1057 	hw->readiness = mei_txe_readiness_get(dev);
1058 
1059 	/* Readiness:
1060 	 * Detection of TXE driver going through reset
1061 	 * or TXE driver resetting the HECI interface.
1062 	 */
1063 	if (test_and_clear_bit(TXE_INTR_READINESS_BIT, &hw->intr_cause)) {
1064 		dev_dbg(dev->dev, "Readiness Interrupt was received...\n");
1065 
1066 		/* Check if SeC is going through reset */
1067 		if (mei_txe_readiness_is_sec_rdy(hw->readiness)) {
1068 			dev_dbg(dev->dev, "we need to start the dev.\n");
1069 			dev->recvd_hw_ready = true;
1070 		} else {
1071 			dev->recvd_hw_ready = false;
1072 			if (dev->dev_state != MEI_DEV_RESETTING) {
1073 
1074 				dev_warn(dev->dev, "FW not ready: resetting.\n");
1075 				schedule_work(&dev->reset_work);
1076 				goto end;
1077 
1078 			}
1079 		}
1080 		wake_up(&dev->wait_hw_ready);
1081 	}
1082 
1083 	/************************************************************/
1084 	/* Check interrupt cause:
1085 	 * Aliveness: Detection of SeC acknowledge of host request that
1086 	 * it remain alive or host cancellation of that request.
1087 	 */
1088 
1089 	if (test_and_clear_bit(TXE_INTR_ALIVENESS_BIT, &hw->intr_cause)) {
1090 		/* Clear the interrupt cause */
1091 		dev_dbg(dev->dev,
1092 			"Aliveness Interrupt: Status: %d\n", hw->aliveness);
1093 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
1094 		if (waitqueue_active(&hw->wait_aliveness_resp))
1095 			wake_up(&hw->wait_aliveness_resp);
1096 	}
1097 
1098 
1099 	/* Output Doorbell:
1100 	 * Detection of SeC having sent output to host
1101 	 */
1102 	slots = mei_count_full_read_slots(dev);
1103 	if (test_and_clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause)) {
1104 		/* Read from TXE */
1105 		rets = mei_irq_read_handler(dev, &complete_list, &slots);
1106 		if (rets && dev->dev_state != MEI_DEV_RESETTING) {
1107 			dev_err(dev->dev,
1108 				"mei_irq_read_handler ret = %d.\n", rets);
1109 
1110 			schedule_work(&dev->reset_work);
1111 			goto end;
1112 		}
1113 	}
1114 	/* Input Ready: Detection if host can write to SeC */
1115 	if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause)) {
1116 		dev->hbuf_is_ready = true;
1117 		hw->slots = dev->hbuf_depth;
1118 	}
1119 
1120 	if (hw->aliveness && dev->hbuf_is_ready) {
1121 		/* get the real register value */
1122 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1123 		rets = mei_irq_write_handler(dev, &complete_list);
1124 		if (rets && rets != -EMSGSIZE)
1125 			dev_err(dev->dev, "mei_irq_write_handler ret = %d.\n",
1126 				rets);
1127 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1128 	}
1129 
1130 	mei_irq_compl_handler(dev, &complete_list);
1131 
1132 end:
1133 	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
1134 
1135 	mutex_unlock(&dev->device_lock);
1136 
1137 	mei_enable_interrupts(dev);
1138 	return IRQ_HANDLED;
1139 }
1140 
1141 static const struct mei_hw_ops mei_txe_hw_ops = {
1142 
1143 	.host_is_ready = mei_txe_host_is_ready,
1144 
1145 	.fw_status = mei_txe_fw_status,
1146 	.pg_state = mei_txe_pg_state,
1147 
1148 	.hw_is_ready = mei_txe_hw_is_ready,
1149 	.hw_reset = mei_txe_hw_reset,
1150 	.hw_config = mei_txe_hw_config,
1151 	.hw_start = mei_txe_hw_start,
1152 
1153 	.pg_in_transition = mei_txe_pg_in_transition,
1154 	.pg_is_enabled = mei_txe_pg_is_enabled,
1155 
1156 	.intr_clear = mei_txe_intr_clear,
1157 	.intr_enable = mei_txe_intr_enable,
1158 	.intr_disable = mei_txe_intr_disable,
1159 
1160 	.hbuf_free_slots = mei_txe_hbuf_empty_slots,
1161 	.hbuf_is_ready = mei_txe_is_input_ready,
1162 	.hbuf_max_len = mei_txe_hbuf_max_len,
1163 
1164 	.write = mei_txe_write,
1165 
1166 	.rdbuf_full_slots = mei_txe_count_full_read_slots,
1167 	.read_hdr = mei_txe_read_hdr,
1168 
1169 	.read = mei_txe_read,
1170 
1171 };
1172 
1173 /**
1174  * mei_txe_dev_init - allocates and initializes txe hardware specific structure
1175  *
1176  * @pdev: pci device
1177  *
1178  * Return: struct mei_device * on success or NULL
1179  */
1180 struct mei_device *mei_txe_dev_init(struct pci_dev *pdev)
1181 {
1182 	struct mei_device *dev;
1183 	struct mei_txe_hw *hw;
1184 
1185 	dev = kzalloc(sizeof(struct mei_device) +
1186 			 sizeof(struct mei_txe_hw), GFP_KERNEL);
1187 	if (!dev)
1188 		return NULL;
1189 
1190 	mei_device_init(dev, &pdev->dev, &mei_txe_hw_ops);
1191 
1192 	hw = to_txe_hw(dev);
1193 
1194 	init_waitqueue_head(&hw->wait_aliveness_resp);
1195 
1196 	return dev;
1197 }
1198 
1199 /**
1200  * mei_txe_setup_satt2 - SATT2 configuration for DMA support.
1201  *
1202  * @dev:   the device structure
1203  * @addr:  physical address start of the range
1204  * @range: physical range size
1205  *
1206  * Return: 0 on success an error code otherwise
1207  */
1208 int mei_txe_setup_satt2(struct mei_device *dev, phys_addr_t addr, u32 range)
1209 {
1210 	struct mei_txe_hw *hw = to_txe_hw(dev);
1211 
1212 	u32 lo32 = lower_32_bits(addr);
1213 	u32 hi32 = upper_32_bits(addr);
1214 	u32 ctrl;
1215 
1216 	/* SATT is limited to 36 Bits */
1217 	if (hi32 & ~0xF)
1218 		return -EINVAL;
1219 
1220 	/* SATT has to be 16Byte aligned */
1221 	if (lo32 & 0xF)
1222 		return -EINVAL;
1223 
1224 	/* SATT range has to be 4Bytes aligned */
1225 	if (range & 0x4)
1226 		return -EINVAL;
1227 
1228 	/* SATT is limited to 32 MB range*/
1229 	if (range > SATT_RANGE_MAX)
1230 		return -EINVAL;
1231 
1232 	ctrl = SATT2_CTRL_VALID_MSK;
1233 	ctrl |= hi32  << SATT2_CTRL_BR_BASE_ADDR_REG_SHIFT;
1234 
1235 	mei_txe_br_reg_write(hw, SATT2_SAP_SIZE_REG, range);
1236 	mei_txe_br_reg_write(hw, SATT2_BRG_BA_LSB_REG, lo32);
1237 	mei_txe_br_reg_write(hw, SATT2_CTRL_REG, ctrl);
1238 	dev_dbg(dev->dev, "SATT2: SAP_SIZE_OFFSET=0x%08X, BRG_BA_LSB_OFFSET=0x%08X, CTRL_OFFSET=0x%08X\n",
1239 		range, lo32, ctrl);
1240 
1241 	return 0;
1242 }
1243