xref: /linux/drivers/misc/mei/hw-txe.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
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 #include <linux/pm_runtime.h>
24 
25 #include <linux/mei.h>
26 
27 #include "mei_dev.h"
28 #include "hw-txe.h"
29 #include "client.h"
30 #include "hbm.h"
31 
32 #include "mei-trace.h"
33 
34 
35 /**
36  * mei_txe_reg_read - Reads 32bit data from the txe device
37  *
38  * @base_addr: registers base address
39  * @offset: register offset
40  *
41  * Return: register value
42  */
43 static inline u32 mei_txe_reg_read(void __iomem *base_addr,
44 					unsigned long offset)
45 {
46 	return ioread32(base_addr + offset);
47 }
48 
49 /**
50  * mei_txe_reg_write - Writes 32bit data to the txe device
51  *
52  * @base_addr: registers base address
53  * @offset: register offset
54  * @value: the value to write
55  */
56 static inline void mei_txe_reg_write(void __iomem *base_addr,
57 				unsigned long offset, u32 value)
58 {
59 	iowrite32(value, base_addr + offset);
60 }
61 
62 /**
63  * mei_txe_sec_reg_read_silent - Reads 32bit data from the SeC BAR
64  *
65  * @hw: the txe hardware structure
66  * @offset: register offset
67  *
68  * Doesn't check for aliveness while Reads 32bit data from the SeC BAR
69  *
70  * Return: register value
71  */
72 static inline u32 mei_txe_sec_reg_read_silent(struct mei_txe_hw *hw,
73 				unsigned long offset)
74 {
75 	return mei_txe_reg_read(hw->mem_addr[SEC_BAR], offset);
76 }
77 
78 /**
79  * mei_txe_sec_reg_read - Reads 32bit data from the SeC BAR
80  *
81  * @hw: the txe hardware structure
82  * @offset: register offset
83  *
84  * Reads 32bit data from the SeC BAR and shout loud if aliveness is not set
85  *
86  * Return: register value
87  */
88 static inline u32 mei_txe_sec_reg_read(struct mei_txe_hw *hw,
89 				unsigned long offset)
90 {
91 	WARN(!hw->aliveness, "sec read: aliveness not asserted\n");
92 	return mei_txe_sec_reg_read_silent(hw, offset);
93 }
94 /**
95  * mei_txe_sec_reg_write_silent - Writes 32bit data to the SeC BAR
96  *   doesn't check for aliveness
97  *
98  * @hw: the txe hardware structure
99  * @offset: register offset
100  * @value: value to write
101  *
102  * Doesn't check for aliveness while writes 32bit data from to the SeC BAR
103  */
104 static inline void mei_txe_sec_reg_write_silent(struct mei_txe_hw *hw,
105 				unsigned long offset, u32 value)
106 {
107 	mei_txe_reg_write(hw->mem_addr[SEC_BAR], offset, value);
108 }
109 
110 /**
111  * mei_txe_sec_reg_write - Writes 32bit data to the SeC BAR
112  *
113  * @hw: the txe hardware structure
114  * @offset: register offset
115  * @value: value to write
116  *
117  * Writes 32bit data from the SeC BAR and shout loud if aliveness is not set
118  */
119 static inline void mei_txe_sec_reg_write(struct mei_txe_hw *hw,
120 				unsigned long offset, u32 value)
121 {
122 	WARN(!hw->aliveness, "sec write: aliveness not asserted\n");
123 	mei_txe_sec_reg_write_silent(hw, offset, value);
124 }
125 /**
126  * mei_txe_br_reg_read - Reads 32bit data from the Bridge BAR
127  *
128  * @hw: the txe hardware structure
129  * @offset: offset from which to read the data
130  *
131  * Return: the byte read.
132  */
133 static inline u32 mei_txe_br_reg_read(struct mei_txe_hw *hw,
134 				unsigned long offset)
135 {
136 	return mei_txe_reg_read(hw->mem_addr[BRIDGE_BAR], offset);
137 }
138 
139 /**
140  * mei_txe_br_reg_write - Writes 32bit data to the Bridge BAR
141  *
142  * @hw: the txe hardware structure
143  * @offset: offset from which to write the data
144  * @value: the byte to write
145  */
146 static inline void mei_txe_br_reg_write(struct mei_txe_hw *hw,
147 				unsigned long offset, u32 value)
148 {
149 	mei_txe_reg_write(hw->mem_addr[BRIDGE_BAR], offset, value);
150 }
151 
152 /**
153  * mei_txe_aliveness_set - request for aliveness change
154  *
155  * @dev: the device structure
156  * @req: requested aliveness value
157  *
158  * Request for aliveness change and returns true if the change is
159  *   really needed and false if aliveness is already
160  *   in the requested state
161  *
162  * Locking: called under "dev->device_lock" lock
163  *
164  * Return: true if request was send
165  */
166 static bool mei_txe_aliveness_set(struct mei_device *dev, u32 req)
167 {
168 
169 	struct mei_txe_hw *hw = to_txe_hw(dev);
170 	bool do_req = hw->aliveness != req;
171 
172 	dev_dbg(dev->dev, "Aliveness current=%d request=%d\n",
173 				hw->aliveness, req);
174 	if (do_req) {
175 		dev->pg_event = MEI_PG_EVENT_WAIT;
176 		mei_txe_br_reg_write(hw, SICR_HOST_ALIVENESS_REQ_REG, req);
177 	}
178 	return do_req;
179 }
180 
181 
182 /**
183  * mei_txe_aliveness_req_get - get aliveness requested register value
184  *
185  * @dev: the device structure
186  *
187  * Extract HICR_HOST_ALIVENESS_RESP_ACK bit from
188  * from HICR_HOST_ALIVENESS_REQ register value
189  *
190  * Return: SICR_HOST_ALIVENESS_REQ_REQUESTED bit value
191  */
192 static u32 mei_txe_aliveness_req_get(struct mei_device *dev)
193 {
194 	struct mei_txe_hw *hw = to_txe_hw(dev);
195 	u32 reg;
196 
197 	reg = mei_txe_br_reg_read(hw, SICR_HOST_ALIVENESS_REQ_REG);
198 	return reg & SICR_HOST_ALIVENESS_REQ_REQUESTED;
199 }
200 
201 /**
202  * mei_txe_aliveness_get - get aliveness response register value
203  *
204  * @dev: the device structure
205  *
206  * Return: HICR_HOST_ALIVENESS_RESP_ACK bit from HICR_HOST_ALIVENESS_RESP
207  *         register
208  */
209 static u32 mei_txe_aliveness_get(struct mei_device *dev)
210 {
211 	struct mei_txe_hw *hw = to_txe_hw(dev);
212 	u32 reg;
213 
214 	reg = mei_txe_br_reg_read(hw, HICR_HOST_ALIVENESS_RESP_REG);
215 	return reg & HICR_HOST_ALIVENESS_RESP_ACK;
216 }
217 
218 /**
219  * mei_txe_aliveness_poll - waits for aliveness to settle
220  *
221  * @dev: the device structure
222  * @expected: expected aliveness value
223  *
224  * Polls for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
225  *
226  * Return: 0 if the expected value was received, -ETIME otherwise
227  */
228 static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
229 {
230 	struct mei_txe_hw *hw = to_txe_hw(dev);
231 	ktime_t stop, start;
232 
233 	start = ktime_get();
234 	stop = ktime_add(start, ms_to_ktime(SEC_ALIVENESS_WAIT_TIMEOUT));
235 	do {
236 		hw->aliveness = mei_txe_aliveness_get(dev);
237 		if (hw->aliveness == expected) {
238 			dev->pg_event = MEI_PG_EVENT_IDLE;
239 			dev_dbg(dev->dev, "aliveness settled after %lld usecs\n",
240 				ktime_to_us(ktime_sub(ktime_get(), start)));
241 			return 0;
242 		}
243 		usleep_range(20, 50);
244 	} while (ktime_before(ktime_get(), stop));
245 
246 	dev->pg_event = MEI_PG_EVENT_IDLE;
247 	dev_err(dev->dev, "aliveness timed out\n");
248 	return -ETIME;
249 }
250 
251 /**
252  * mei_txe_aliveness_wait - waits for aliveness to settle
253  *
254  * @dev: the device structure
255  * @expected: expected aliveness value
256  *
257  * Waits for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
258  *
259  * Return: 0 on success and < 0 otherwise
260  */
261 static int mei_txe_aliveness_wait(struct mei_device *dev, u32 expected)
262 {
263 	struct mei_txe_hw *hw = to_txe_hw(dev);
264 	const unsigned long timeout =
265 			msecs_to_jiffies(SEC_ALIVENESS_WAIT_TIMEOUT);
266 	long err;
267 	int ret;
268 
269 	hw->aliveness = mei_txe_aliveness_get(dev);
270 	if (hw->aliveness == expected)
271 		return 0;
272 
273 	mutex_unlock(&dev->device_lock);
274 	err = wait_event_timeout(hw->wait_aliveness_resp,
275 			dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
276 	mutex_lock(&dev->device_lock);
277 
278 	hw->aliveness = mei_txe_aliveness_get(dev);
279 	ret = hw->aliveness == expected ? 0 : -ETIME;
280 
281 	if (ret)
282 		dev_warn(dev->dev, "aliveness timed out = %ld aliveness = %d event = %d\n",
283 			err, hw->aliveness, dev->pg_event);
284 	else
285 		dev_dbg(dev->dev, "aliveness settled after = %d msec aliveness = %d event = %d\n",
286 			jiffies_to_msecs(timeout - err),
287 			hw->aliveness, dev->pg_event);
288 
289 	dev->pg_event = MEI_PG_EVENT_IDLE;
290 	return ret;
291 }
292 
293 /**
294  * mei_txe_aliveness_set_sync - sets an wait for aliveness to complete
295  *
296  * @dev: the device structure
297  * @req: requested aliveness value
298  *
299  * Return: 0 on success and < 0 otherwise
300  */
301 int mei_txe_aliveness_set_sync(struct mei_device *dev, u32 req)
302 {
303 	if (mei_txe_aliveness_set(dev, req))
304 		return mei_txe_aliveness_wait(dev, req);
305 	return 0;
306 }
307 
308 /**
309  * mei_txe_pg_in_transition - is device now in pg transition
310  *
311  * @dev: the device structure
312  *
313  * Return: true if in pg transition, false otherwise
314  */
315 static bool mei_txe_pg_in_transition(struct mei_device *dev)
316 {
317 	return dev->pg_event == MEI_PG_EVENT_WAIT;
318 }
319 
320 /**
321  * mei_txe_pg_is_enabled - detect if PG is supported by HW
322  *
323  * @dev: the device structure
324  *
325  * Return: true is pg supported, false otherwise
326  */
327 static bool mei_txe_pg_is_enabled(struct mei_device *dev)
328 {
329 	return true;
330 }
331 
332 /**
333  * mei_txe_pg_state  - translate aliveness register value
334  *   to the mei power gating state
335  *
336  * @dev: the device structure
337  *
338  * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
339  */
340 static inline enum mei_pg_state mei_txe_pg_state(struct mei_device *dev)
341 {
342 	struct mei_txe_hw *hw = to_txe_hw(dev);
343 
344 	return hw->aliveness ? MEI_PG_OFF : MEI_PG_ON;
345 }
346 
347 /**
348  * mei_txe_input_ready_interrupt_enable - sets the Input Ready Interrupt
349  *
350  * @dev: the device structure
351  */
352 static void mei_txe_input_ready_interrupt_enable(struct mei_device *dev)
353 {
354 	struct mei_txe_hw *hw = to_txe_hw(dev);
355 	u32 hintmsk;
356 	/* Enable the SEC_IPC_HOST_INT_MASK_IN_RDY interrupt */
357 	hintmsk = mei_txe_sec_reg_read(hw, SEC_IPC_HOST_INT_MASK_REG);
358 	hintmsk |= SEC_IPC_HOST_INT_MASK_IN_RDY;
359 	mei_txe_sec_reg_write(hw, SEC_IPC_HOST_INT_MASK_REG, hintmsk);
360 }
361 
362 /**
363  * mei_txe_input_doorbell_set - sets bit 0 in
364  *    SEC_IPC_INPUT_DOORBELL.IPC_INPUT_DOORBELL.
365  *
366  * @hw: the txe hardware structure
367  */
368 static void mei_txe_input_doorbell_set(struct mei_txe_hw *hw)
369 {
370 	/* Clear the interrupt cause */
371 	clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause);
372 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_DOORBELL_REG, 1);
373 }
374 
375 /**
376  * mei_txe_output_ready_set - Sets the SICR_SEC_IPC_OUTPUT_STATUS bit to 1
377  *
378  * @hw: the txe hardware structure
379  */
380 static void mei_txe_output_ready_set(struct mei_txe_hw *hw)
381 {
382 	mei_txe_br_reg_write(hw,
383 			SICR_SEC_IPC_OUTPUT_STATUS_REG,
384 			SEC_IPC_OUTPUT_STATUS_RDY);
385 }
386 
387 /**
388  * mei_txe_is_input_ready - check if TXE is ready for receiving data
389  *
390  * @dev: the device structure
391  *
392  * Return: true if INPUT STATUS READY bit is set
393  */
394 static bool mei_txe_is_input_ready(struct mei_device *dev)
395 {
396 	struct mei_txe_hw *hw = to_txe_hw(dev);
397 	u32 status;
398 
399 	status = mei_txe_sec_reg_read(hw, SEC_IPC_INPUT_STATUS_REG);
400 	return !!(SEC_IPC_INPUT_STATUS_RDY & status);
401 }
402 
403 /**
404  * mei_txe_intr_clear - clear all interrupts
405  *
406  * @dev: the device structure
407  */
408 static inline void mei_txe_intr_clear(struct mei_device *dev)
409 {
410 	struct mei_txe_hw *hw = to_txe_hw(dev);
411 
412 	mei_txe_sec_reg_write_silent(hw, SEC_IPC_HOST_INT_STATUS_REG,
413 		SEC_IPC_HOST_INT_STATUS_PENDING);
414 	mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_STS_MSK);
415 	mei_txe_br_reg_write(hw, HHISR_REG, IPC_HHIER_MSK);
416 }
417 
418 /**
419  * mei_txe_intr_disable - disable all interrupts
420  *
421  * @dev: the device structure
422  */
423 static void mei_txe_intr_disable(struct mei_device *dev)
424 {
425 	struct mei_txe_hw *hw = to_txe_hw(dev);
426 
427 	mei_txe_br_reg_write(hw, HHIER_REG, 0);
428 	mei_txe_br_reg_write(hw, HIER_REG, 0);
429 }
430 /**
431  * mei_txe_intr_enable - enable all interrupts
432  *
433  * @dev: the device structure
434  */
435 static void mei_txe_intr_enable(struct mei_device *dev)
436 {
437 	struct mei_txe_hw *hw = to_txe_hw(dev);
438 
439 	mei_txe_br_reg_write(hw, HHIER_REG, IPC_HHIER_MSK);
440 	mei_txe_br_reg_write(hw, HIER_REG, HIER_INT_EN_MSK);
441 }
442 
443 /**
444  * mei_txe_pending_interrupts - check if there are pending interrupts
445  *	only Aliveness, Input ready, and output doorbell are of relevance
446  *
447  * @dev: the device structure
448  *
449  * Checks if there are pending interrupts
450  * only Aliveness, Readiness, Input ready, and Output doorbell are relevant
451  *
452  * Return: true if there are pending interrupts
453  */
454 static bool mei_txe_pending_interrupts(struct mei_device *dev)
455 {
456 
457 	struct mei_txe_hw *hw = to_txe_hw(dev);
458 	bool ret = (hw->intr_cause & (TXE_INTR_READINESS |
459 				      TXE_INTR_ALIVENESS |
460 				      TXE_INTR_IN_READY  |
461 				      TXE_INTR_OUT_DB));
462 
463 	if (ret) {
464 		dev_dbg(dev->dev,
465 			"Pending Interrupts InReady=%01d Readiness=%01d, Aliveness=%01d, OutDoor=%01d\n",
466 			!!(hw->intr_cause & TXE_INTR_IN_READY),
467 			!!(hw->intr_cause & TXE_INTR_READINESS),
468 			!!(hw->intr_cause & TXE_INTR_ALIVENESS),
469 			!!(hw->intr_cause & TXE_INTR_OUT_DB));
470 	}
471 	return ret;
472 }
473 
474 /**
475  * mei_txe_input_payload_write - write a dword to the host buffer
476  *	at offset idx
477  *
478  * @dev: the device structure
479  * @idx: index in the host buffer
480  * @value: value
481  */
482 static void mei_txe_input_payload_write(struct mei_device *dev,
483 			unsigned long idx, u32 value)
484 {
485 	struct mei_txe_hw *hw = to_txe_hw(dev);
486 
487 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_PAYLOAD_REG +
488 			(idx * sizeof(u32)), value);
489 }
490 
491 /**
492  * mei_txe_out_data_read - read dword from the device buffer
493  *	at offset idx
494  *
495  * @dev: the device structure
496  * @idx: index in the device buffer
497  *
498  * Return: register value at index
499  */
500 static u32 mei_txe_out_data_read(const struct mei_device *dev,
501 					unsigned long idx)
502 {
503 	struct mei_txe_hw *hw = to_txe_hw(dev);
504 
505 	return mei_txe_br_reg_read(hw,
506 		BRIDGE_IPC_OUTPUT_PAYLOAD_REG + (idx * sizeof(u32)));
507 }
508 
509 /* Readiness */
510 
511 /**
512  * mei_txe_readiness_set_host_rdy - set host readiness bit
513  *
514  * @dev: the device structure
515  */
516 static void mei_txe_readiness_set_host_rdy(struct mei_device *dev)
517 {
518 	struct mei_txe_hw *hw = to_txe_hw(dev);
519 
520 	mei_txe_br_reg_write(hw,
521 		SICR_HOST_IPC_READINESS_REQ_REG,
522 		SICR_HOST_IPC_READINESS_HOST_RDY);
523 }
524 
525 /**
526  * mei_txe_readiness_clear - clear host readiness bit
527  *
528  * @dev: the device structure
529  */
530 static void mei_txe_readiness_clear(struct mei_device *dev)
531 {
532 	struct mei_txe_hw *hw = to_txe_hw(dev);
533 
534 	mei_txe_br_reg_write(hw, SICR_HOST_IPC_READINESS_REQ_REG,
535 				SICR_HOST_IPC_READINESS_RDY_CLR);
536 }
537 /**
538  * mei_txe_readiness_get - Reads and returns
539  *	the HICR_SEC_IPC_READINESS register value
540  *
541  * @dev: the device structure
542  *
543  * Return: the HICR_SEC_IPC_READINESS register value
544  */
545 static u32 mei_txe_readiness_get(struct mei_device *dev)
546 {
547 	struct mei_txe_hw *hw = to_txe_hw(dev);
548 
549 	return mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
550 }
551 
552 
553 /**
554  * mei_txe_readiness_is_sec_rdy - check readiness
555  *  for HICR_SEC_IPC_READINESS_SEC_RDY
556  *
557  * @readiness: cached readiness state
558  *
559  * Return: true if readiness bit is set
560  */
561 static inline bool mei_txe_readiness_is_sec_rdy(u32 readiness)
562 {
563 	return !!(readiness & HICR_SEC_IPC_READINESS_SEC_RDY);
564 }
565 
566 /**
567  * mei_txe_hw_is_ready - check if the hw is ready
568  *
569  * @dev: the device structure
570  *
571  * Return: true if sec is ready
572  */
573 static bool mei_txe_hw_is_ready(struct mei_device *dev)
574 {
575 	u32 readiness =  mei_txe_readiness_get(dev);
576 
577 	return mei_txe_readiness_is_sec_rdy(readiness);
578 }
579 
580 /**
581  * mei_txe_host_is_ready - check if the host is ready
582  *
583  * @dev: the device structure
584  *
585  * Return: true if host is ready
586  */
587 static inline bool mei_txe_host_is_ready(struct mei_device *dev)
588 {
589 	struct mei_txe_hw *hw = to_txe_hw(dev);
590 	u32 reg = mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
591 
592 	return !!(reg & HICR_SEC_IPC_READINESS_HOST_RDY);
593 }
594 
595 /**
596  * mei_txe_readiness_wait - wait till readiness settles
597  *
598  * @dev: the device structure
599  *
600  * Return: 0 on success and -ETIME on timeout
601  */
602 static int mei_txe_readiness_wait(struct mei_device *dev)
603 {
604 	if (mei_txe_hw_is_ready(dev))
605 		return 0;
606 
607 	mutex_unlock(&dev->device_lock);
608 	wait_event_timeout(dev->wait_hw_ready, dev->recvd_hw_ready,
609 			msecs_to_jiffies(SEC_RESET_WAIT_TIMEOUT));
610 	mutex_lock(&dev->device_lock);
611 	if (!dev->recvd_hw_ready) {
612 		dev_err(dev->dev, "wait for readiness failed\n");
613 		return -ETIME;
614 	}
615 
616 	dev->recvd_hw_ready = false;
617 	return 0;
618 }
619 
620 static const struct mei_fw_status mei_txe_fw_sts = {
621 	.count = 2,
622 	.status[0] = PCI_CFG_TXE_FW_STS0,
623 	.status[1] = PCI_CFG_TXE_FW_STS1
624 };
625 
626 /**
627  * mei_txe_fw_status - read fw status register from pci config space
628  *
629  * @dev: mei device
630  * @fw_status: fw status register values
631  *
632  * Return: 0 on success, error otherwise
633  */
634 static int mei_txe_fw_status(struct mei_device *dev,
635 			     struct mei_fw_status *fw_status)
636 {
637 	const struct mei_fw_status *fw_src = &mei_txe_fw_sts;
638 	struct pci_dev *pdev = to_pci_dev(dev->dev);
639 	int ret;
640 	int i;
641 
642 	if (!fw_status)
643 		return -EINVAL;
644 
645 	fw_status->count = fw_src->count;
646 	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
647 		ret = pci_read_config_dword(pdev, fw_src->status[i],
648 					    &fw_status->status[i]);
649 		trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HSF_X",
650 				       fw_src->status[i],
651 				       fw_status->status[i]);
652 		if (ret)
653 			return ret;
654 	}
655 
656 	return 0;
657 }
658 
659 /**
660  *  mei_txe_hw_config - configure hardware at the start of the devices
661  *
662  * @dev: the device structure
663  *
664  * Configure hardware at the start of the device should be done only
665  *   once at the device probe time
666  */
667 static void mei_txe_hw_config(struct mei_device *dev)
668 {
669 
670 	struct mei_txe_hw *hw = to_txe_hw(dev);
671 
672 	/* Doesn't change in runtime */
673 	dev->hbuf_depth = PAYLOAD_SIZE / 4;
674 
675 	hw->aliveness = mei_txe_aliveness_get(dev);
676 	hw->readiness = mei_txe_readiness_get(dev);
677 
678 	dev_dbg(dev->dev, "aliveness_resp = 0x%08x, readiness = 0x%08x.\n",
679 		hw->aliveness, hw->readiness);
680 }
681 
682 
683 /**
684  * mei_txe_write - writes a message to device.
685  *
686  * @dev: the device structure
687  * @header: header of message
688  * @buf: message buffer will be written
689  *
690  * Return: 0 if success, <0 - otherwise.
691  */
692 
693 static int mei_txe_write(struct mei_device *dev,
694 		struct mei_msg_hdr *header, unsigned char *buf)
695 {
696 	struct mei_txe_hw *hw = to_txe_hw(dev);
697 	unsigned long rem;
698 	unsigned long length;
699 	int slots = dev->hbuf_depth;
700 	u32 *reg_buf = (u32 *)buf;
701 	u32 dw_cnt;
702 	int i;
703 
704 	if (WARN_ON(!header || !buf))
705 		return -EINVAL;
706 
707 	length = header->length;
708 
709 	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(header));
710 
711 	dw_cnt = mei_data2slots(length);
712 	if (dw_cnt > slots)
713 		return -EMSGSIZE;
714 
715 	if (WARN(!hw->aliveness, "txe write: aliveness not asserted\n"))
716 		return -EAGAIN;
717 
718 	/* Enable Input Ready Interrupt. */
719 	mei_txe_input_ready_interrupt_enable(dev);
720 
721 	if (!mei_txe_is_input_ready(dev)) {
722 		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
723 
724 		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
725 		dev_err(dev->dev, "Input is not ready %s\n", fw_sts_str);
726 		return -EAGAIN;
727 	}
728 
729 	mei_txe_input_payload_write(dev, 0, *((u32 *)header));
730 
731 	for (i = 0; i < length / 4; i++)
732 		mei_txe_input_payload_write(dev, i + 1, reg_buf[i]);
733 
734 	rem = length & 0x3;
735 	if (rem > 0) {
736 		u32 reg = 0;
737 
738 		memcpy(&reg, &buf[length - rem], rem);
739 		mei_txe_input_payload_write(dev, i + 1, reg);
740 	}
741 
742 	/* after each write the whole buffer is consumed */
743 	hw->slots = 0;
744 
745 	/* Set Input-Doorbell */
746 	mei_txe_input_doorbell_set(hw);
747 
748 	return 0;
749 }
750 
751 /**
752  * mei_txe_hbuf_max_len - mimics the me hbuf circular buffer
753  *
754  * @dev: the device structure
755  *
756  * Return: the PAYLOAD_SIZE - 4
757  */
758 static size_t mei_txe_hbuf_max_len(const struct mei_device *dev)
759 {
760 	return PAYLOAD_SIZE - sizeof(struct mei_msg_hdr);
761 }
762 
763 /**
764  * mei_txe_hbuf_empty_slots - mimics the me hbuf circular buffer
765  *
766  * @dev: the device structure
767  *
768  * Return: always hbuf_depth
769  */
770 static int mei_txe_hbuf_empty_slots(struct mei_device *dev)
771 {
772 	struct mei_txe_hw *hw = to_txe_hw(dev);
773 
774 	return hw->slots;
775 }
776 
777 /**
778  * mei_txe_count_full_read_slots - mimics the me device circular buffer
779  *
780  * @dev: the device structure
781  *
782  * Return: always buffer size in dwords count
783  */
784 static int mei_txe_count_full_read_slots(struct mei_device *dev)
785 {
786 	/* read buffers has static size */
787 	return  PAYLOAD_SIZE / 4;
788 }
789 
790 /**
791  * mei_txe_read_hdr - read message header which is always in 4 first bytes
792  *
793  * @dev: the device structure
794  *
795  * Return: mei message header
796  */
797 
798 static u32 mei_txe_read_hdr(const struct mei_device *dev)
799 {
800 	return mei_txe_out_data_read(dev, 0);
801 }
802 /**
803  * mei_txe_read - reads a message from the txe device.
804  *
805  * @dev: the device structure
806  * @buf: message buffer will be written
807  * @len: message size will be read
808  *
809  * Return: -EINVAL on error wrong argument and 0 on success
810  */
811 static int mei_txe_read(struct mei_device *dev,
812 		unsigned char *buf, unsigned long len)
813 {
814 
815 	struct mei_txe_hw *hw = to_txe_hw(dev);
816 	u32 *reg_buf, reg;
817 	u32 rem;
818 	u32 i;
819 
820 	if (WARN_ON(!buf || !len))
821 		return -EINVAL;
822 
823 	reg_buf = (u32 *)buf;
824 	rem = len & 0x3;
825 
826 	dev_dbg(dev->dev, "buffer-length = %lu buf[0]0x%08X\n",
827 		len, mei_txe_out_data_read(dev, 0));
828 
829 	for (i = 0; i < len / 4; i++) {
830 		/* skip header: index starts from 1 */
831 		reg = mei_txe_out_data_read(dev, i + 1);
832 		dev_dbg(dev->dev, "buf[%d] = 0x%08X\n", i, reg);
833 		*reg_buf++ = reg;
834 	}
835 
836 	if (rem) {
837 		reg = mei_txe_out_data_read(dev, i + 1);
838 		memcpy(reg_buf, &reg, rem);
839 	}
840 
841 	mei_txe_output_ready_set(hw);
842 	return 0;
843 }
844 
845 /**
846  * mei_txe_hw_reset - resets host and fw.
847  *
848  * @dev: the device structure
849  * @intr_enable: if interrupt should be enabled after reset.
850  *
851  * Return: 0 on success and < 0 in case of error
852  */
853 static int mei_txe_hw_reset(struct mei_device *dev, bool intr_enable)
854 {
855 	struct mei_txe_hw *hw = to_txe_hw(dev);
856 
857 	u32 aliveness_req;
858 	/*
859 	 * read input doorbell to ensure consistency between  Bridge and SeC
860 	 * return value might be garbage return
861 	 */
862 	(void)mei_txe_sec_reg_read_silent(hw, SEC_IPC_INPUT_DOORBELL_REG);
863 
864 	aliveness_req = mei_txe_aliveness_req_get(dev);
865 	hw->aliveness = mei_txe_aliveness_get(dev);
866 
867 	/* Disable interrupts in this stage we will poll */
868 	mei_txe_intr_disable(dev);
869 
870 	/*
871 	 * If Aliveness Request and Aliveness Response are not equal then
872 	 * wait for them to be equal
873 	 * Since we might have interrupts disabled - poll for it
874 	 */
875 	if (aliveness_req != hw->aliveness)
876 		if (mei_txe_aliveness_poll(dev, aliveness_req) < 0) {
877 			dev_err(dev->dev, "wait for aliveness settle failed ... bailing out\n");
878 			return -EIO;
879 		}
880 
881 	/*
882 	 * If Aliveness Request and Aliveness Response are set then clear them
883 	 */
884 	if (aliveness_req) {
885 		mei_txe_aliveness_set(dev, 0);
886 		if (mei_txe_aliveness_poll(dev, 0) < 0) {
887 			dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
888 			return -EIO;
889 		}
890 	}
891 
892 	/*
893 	 * Set readiness RDY_CLR bit
894 	 */
895 	mei_txe_readiness_clear(dev);
896 
897 	return 0;
898 }
899 
900 /**
901  * mei_txe_hw_start - start the hardware after reset
902  *
903  * @dev: the device structure
904  *
905  * Return: 0 on success an error code otherwise
906  */
907 static int mei_txe_hw_start(struct mei_device *dev)
908 {
909 	struct mei_txe_hw *hw = to_txe_hw(dev);
910 	int ret;
911 
912 	u32 hisr;
913 
914 	/* bring back interrupts */
915 	mei_txe_intr_enable(dev);
916 
917 	ret = mei_txe_readiness_wait(dev);
918 	if (ret < 0) {
919 		dev_err(dev->dev, "waiting for readiness failed\n");
920 		return ret;
921 	}
922 
923 	/*
924 	 * If HISR.INT2_STS interrupt status bit is set then clear it.
925 	 */
926 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
927 	if (hisr & HISR_INT_2_STS)
928 		mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_2_STS);
929 
930 	/* Clear the interrupt cause of OutputDoorbell */
931 	clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause);
932 
933 	ret = mei_txe_aliveness_set_sync(dev, 1);
934 	if (ret < 0) {
935 		dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
936 		return ret;
937 	}
938 
939 	pm_runtime_set_active(dev->dev);
940 
941 	/* enable input ready interrupts:
942 	 * SEC_IPC_HOST_INT_MASK.IPC_INPUT_READY_INT_MASK
943 	 */
944 	mei_txe_input_ready_interrupt_enable(dev);
945 
946 
947 	/*  Set the SICR_SEC_IPC_OUTPUT_STATUS.IPC_OUTPUT_READY bit */
948 	mei_txe_output_ready_set(hw);
949 
950 	/* Set bit SICR_HOST_IPC_READINESS.HOST_RDY
951 	 */
952 	mei_txe_readiness_set_host_rdy(dev);
953 
954 	return 0;
955 }
956 
957 /**
958  * mei_txe_check_and_ack_intrs - translate multi BAR interrupt into
959  *  single bit mask and acknowledge the interrupts
960  *
961  * @dev: the device structure
962  * @do_ack: acknowledge interrupts
963  *
964  * Return: true if found interrupts to process.
965  */
966 static bool mei_txe_check_and_ack_intrs(struct mei_device *dev, bool do_ack)
967 {
968 	struct mei_txe_hw *hw = to_txe_hw(dev);
969 	u32 hisr;
970 	u32 hhisr;
971 	u32 ipc_isr;
972 	u32 aliveness;
973 	bool generated;
974 
975 	/* read interrupt registers */
976 	hhisr = mei_txe_br_reg_read(hw, HHISR_REG);
977 	generated = (hhisr & IPC_HHIER_MSK);
978 	if (!generated)
979 		goto out;
980 
981 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
982 
983 	aliveness = mei_txe_aliveness_get(dev);
984 	if (hhisr & IPC_HHIER_SEC && aliveness) {
985 		ipc_isr = mei_txe_sec_reg_read_silent(hw,
986 				SEC_IPC_HOST_INT_STATUS_REG);
987 	} else {
988 		ipc_isr = 0;
989 		hhisr &= ~IPC_HHIER_SEC;
990 	}
991 
992 	generated = generated ||
993 		(hisr & HISR_INT_STS_MSK) ||
994 		(ipc_isr & SEC_IPC_HOST_INT_STATUS_PENDING);
995 
996 	if (generated && do_ack) {
997 		/* Save the interrupt causes */
998 		hw->intr_cause |= hisr & HISR_INT_STS_MSK;
999 		if (ipc_isr & SEC_IPC_HOST_INT_STATUS_IN_RDY)
1000 			hw->intr_cause |= TXE_INTR_IN_READY;
1001 
1002 
1003 		mei_txe_intr_disable(dev);
1004 		/* Clear the interrupts in hierarchy:
1005 		 * IPC and Bridge, than the High Level */
1006 		mei_txe_sec_reg_write_silent(hw,
1007 			SEC_IPC_HOST_INT_STATUS_REG, ipc_isr);
1008 		mei_txe_br_reg_write(hw, HISR_REG, hisr);
1009 		mei_txe_br_reg_write(hw, HHISR_REG, hhisr);
1010 	}
1011 
1012 out:
1013 	return generated;
1014 }
1015 
1016 /**
1017  * mei_txe_irq_quick_handler - The ISR of the MEI device
1018  *
1019  * @irq: The irq number
1020  * @dev_id: pointer to the device structure
1021  *
1022  * Return: IRQ_WAKE_THREAD if interrupt is designed for the device
1023  *         IRQ_NONE otherwise
1024  */
1025 irqreturn_t mei_txe_irq_quick_handler(int irq, void *dev_id)
1026 {
1027 	struct mei_device *dev = dev_id;
1028 
1029 	if (mei_txe_check_and_ack_intrs(dev, true))
1030 		return IRQ_WAKE_THREAD;
1031 	return IRQ_NONE;
1032 }
1033 
1034 
1035 /**
1036  * mei_txe_irq_thread_handler - txe interrupt thread
1037  *
1038  * @irq: The irq number
1039  * @dev_id: pointer to the device structure
1040  *
1041  * Return: IRQ_HANDLED
1042  */
1043 irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
1044 {
1045 	struct mei_device *dev = (struct mei_device *) dev_id;
1046 	struct mei_txe_hw *hw = to_txe_hw(dev);
1047 	struct mei_cl_cb complete_list;
1048 	s32 slots;
1049 	int rets = 0;
1050 
1051 	dev_dbg(dev->dev, "irq thread: Interrupt Registers HHISR|HISR|SEC=%02X|%04X|%02X\n",
1052 		mei_txe_br_reg_read(hw, HHISR_REG),
1053 		mei_txe_br_reg_read(hw, HISR_REG),
1054 		mei_txe_sec_reg_read_silent(hw, SEC_IPC_HOST_INT_STATUS_REG));
1055 
1056 
1057 	/* initialize our complete list */
1058 	mutex_lock(&dev->device_lock);
1059 	mei_io_list_init(&complete_list);
1060 
1061 	if (pci_dev_msi_enabled(to_pci_dev(dev->dev)))
1062 		mei_txe_check_and_ack_intrs(dev, true);
1063 
1064 	/* show irq events */
1065 	mei_txe_pending_interrupts(dev);
1066 
1067 	hw->aliveness = mei_txe_aliveness_get(dev);
1068 	hw->readiness = mei_txe_readiness_get(dev);
1069 
1070 	/* Readiness:
1071 	 * Detection of TXE driver going through reset
1072 	 * or TXE driver resetting the HECI interface.
1073 	 */
1074 	if (test_and_clear_bit(TXE_INTR_READINESS_BIT, &hw->intr_cause)) {
1075 		dev_dbg(dev->dev, "Readiness Interrupt was received...\n");
1076 
1077 		/* Check if SeC is going through reset */
1078 		if (mei_txe_readiness_is_sec_rdy(hw->readiness)) {
1079 			dev_dbg(dev->dev, "we need to start the dev.\n");
1080 			dev->recvd_hw_ready = true;
1081 		} else {
1082 			dev->recvd_hw_ready = false;
1083 			if (dev->dev_state != MEI_DEV_RESETTING) {
1084 
1085 				dev_warn(dev->dev, "FW not ready: resetting.\n");
1086 				schedule_work(&dev->reset_work);
1087 				goto end;
1088 
1089 			}
1090 		}
1091 		wake_up(&dev->wait_hw_ready);
1092 	}
1093 
1094 	/************************************************************/
1095 	/* Check interrupt cause:
1096 	 * Aliveness: Detection of SeC acknowledge of host request that
1097 	 * it remain alive or host cancellation of that request.
1098 	 */
1099 
1100 	if (test_and_clear_bit(TXE_INTR_ALIVENESS_BIT, &hw->intr_cause)) {
1101 		/* Clear the interrupt cause */
1102 		dev_dbg(dev->dev,
1103 			"Aliveness Interrupt: Status: %d\n", hw->aliveness);
1104 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
1105 		if (waitqueue_active(&hw->wait_aliveness_resp))
1106 			wake_up(&hw->wait_aliveness_resp);
1107 	}
1108 
1109 
1110 	/* Output Doorbell:
1111 	 * Detection of SeC having sent output to host
1112 	 */
1113 	slots = mei_count_full_read_slots(dev);
1114 	if (test_and_clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause)) {
1115 		/* Read from TXE */
1116 		rets = mei_irq_read_handler(dev, &complete_list, &slots);
1117 		if (rets && dev->dev_state != MEI_DEV_RESETTING) {
1118 			dev_err(dev->dev,
1119 				"mei_irq_read_handler ret = %d.\n", rets);
1120 
1121 			schedule_work(&dev->reset_work);
1122 			goto end;
1123 		}
1124 	}
1125 	/* Input Ready: Detection if host can write to SeC */
1126 	if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause)) {
1127 		dev->hbuf_is_ready = true;
1128 		hw->slots = dev->hbuf_depth;
1129 	}
1130 
1131 	if (hw->aliveness && dev->hbuf_is_ready) {
1132 		/* get the real register value */
1133 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1134 		rets = mei_irq_write_handler(dev, &complete_list);
1135 		if (rets && rets != -EMSGSIZE)
1136 			dev_err(dev->dev, "mei_irq_write_handler ret = %d.\n",
1137 				rets);
1138 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1139 	}
1140 
1141 	mei_irq_compl_handler(dev, &complete_list);
1142 
1143 end:
1144 	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
1145 
1146 	mutex_unlock(&dev->device_lock);
1147 
1148 	mei_enable_interrupts(dev);
1149 	return IRQ_HANDLED;
1150 }
1151 
1152 static const struct mei_hw_ops mei_txe_hw_ops = {
1153 
1154 	.host_is_ready = mei_txe_host_is_ready,
1155 
1156 	.fw_status = mei_txe_fw_status,
1157 	.pg_state = mei_txe_pg_state,
1158 
1159 	.hw_is_ready = mei_txe_hw_is_ready,
1160 	.hw_reset = mei_txe_hw_reset,
1161 	.hw_config = mei_txe_hw_config,
1162 	.hw_start = mei_txe_hw_start,
1163 
1164 	.pg_in_transition = mei_txe_pg_in_transition,
1165 	.pg_is_enabled = mei_txe_pg_is_enabled,
1166 
1167 	.intr_clear = mei_txe_intr_clear,
1168 	.intr_enable = mei_txe_intr_enable,
1169 	.intr_disable = mei_txe_intr_disable,
1170 
1171 	.hbuf_free_slots = mei_txe_hbuf_empty_slots,
1172 	.hbuf_is_ready = mei_txe_is_input_ready,
1173 	.hbuf_max_len = mei_txe_hbuf_max_len,
1174 
1175 	.write = mei_txe_write,
1176 
1177 	.rdbuf_full_slots = mei_txe_count_full_read_slots,
1178 	.read_hdr = mei_txe_read_hdr,
1179 
1180 	.read = mei_txe_read,
1181 
1182 };
1183 
1184 /**
1185  * mei_txe_dev_init - allocates and initializes txe hardware specific structure
1186  *
1187  * @pdev: pci device
1188  *
1189  * Return: struct mei_device * on success or NULL
1190  */
1191 struct mei_device *mei_txe_dev_init(struct pci_dev *pdev)
1192 {
1193 	struct mei_device *dev;
1194 	struct mei_txe_hw *hw;
1195 
1196 	dev = kzalloc(sizeof(struct mei_device) +
1197 			 sizeof(struct mei_txe_hw), GFP_KERNEL);
1198 	if (!dev)
1199 		return NULL;
1200 
1201 	mei_device_init(dev, &pdev->dev, &mei_txe_hw_ops);
1202 
1203 	hw = to_txe_hw(dev);
1204 
1205 	init_waitqueue_head(&hw->wait_aliveness_resp);
1206 
1207 	return dev;
1208 }
1209 
1210 /**
1211  * mei_txe_setup_satt2 - SATT2 configuration for DMA support.
1212  *
1213  * @dev:   the device structure
1214  * @addr:  physical address start of the range
1215  * @range: physical range size
1216  *
1217  * Return: 0 on success an error code otherwise
1218  */
1219 int mei_txe_setup_satt2(struct mei_device *dev, phys_addr_t addr, u32 range)
1220 {
1221 	struct mei_txe_hw *hw = to_txe_hw(dev);
1222 
1223 	u32 lo32 = lower_32_bits(addr);
1224 	u32 hi32 = upper_32_bits(addr);
1225 	u32 ctrl;
1226 
1227 	/* SATT is limited to 36 Bits */
1228 	if (hi32 & ~0xF)
1229 		return -EINVAL;
1230 
1231 	/* SATT has to be 16Byte aligned */
1232 	if (lo32 & 0xF)
1233 		return -EINVAL;
1234 
1235 	/* SATT range has to be 4Bytes aligned */
1236 	if (range & 0x4)
1237 		return -EINVAL;
1238 
1239 	/* SATT is limited to 32 MB range*/
1240 	if (range > SATT_RANGE_MAX)
1241 		return -EINVAL;
1242 
1243 	ctrl = SATT2_CTRL_VALID_MSK;
1244 	ctrl |= hi32  << SATT2_CTRL_BR_BASE_ADDR_REG_SHIFT;
1245 
1246 	mei_txe_br_reg_write(hw, SATT2_SAP_SIZE_REG, range);
1247 	mei_txe_br_reg_write(hw, SATT2_BRG_BA_LSB_REG, lo32);
1248 	mei_txe_br_reg_write(hw, SATT2_CTRL_REG, ctrl);
1249 	dev_dbg(dev->dev, "SATT2: SAP_SIZE_OFFSET=0x%08X, BRG_BA_LSB_OFFSET=0x%08X, CTRL_OFFSET=0x%08X\n",
1250 		range, lo32, ctrl);
1251 
1252 	return 0;
1253 }
1254