xref: /openbmc/linux/drivers/misc/mei/hw-txe.c (revision 78700c0a)
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 #include "mei-trace.h"
32 
33 
34 /**
35  * mei_txe_reg_read - Reads 32bit data from the txe device
36  *
37  * @base_addr: registers base address
38  * @offset: register offset
39  *
40  * Return: register value
41  */
42 static inline u32 mei_txe_reg_read(void __iomem *base_addr,
43 					unsigned long offset)
44 {
45 	return ioread32(base_addr + offset);
46 }
47 
48 /**
49  * mei_txe_reg_write - Writes 32bit data to the txe device
50  *
51  * @base_addr: registers base address
52  * @offset: register offset
53  * @value: the value to write
54  */
55 static inline void mei_txe_reg_write(void __iomem *base_addr,
56 				unsigned long offset, u32 value)
57 {
58 	iowrite32(value, base_addr + offset);
59 }
60 
61 /**
62  * mei_txe_sec_reg_read_silent - Reads 32bit data from the SeC BAR
63  *
64  * @hw: the txe hardware structure
65  * @offset: register offset
66  *
67  * Doesn't check for aliveness while Reads 32bit data from the SeC BAR
68  *
69  * Return: register value
70  */
71 static inline u32 mei_txe_sec_reg_read_silent(struct mei_txe_hw *hw,
72 				unsigned long offset)
73 {
74 	return mei_txe_reg_read(hw->mem_addr[SEC_BAR], offset);
75 }
76 
77 /**
78  * mei_txe_sec_reg_read - Reads 32bit data from the SeC BAR
79  *
80  * @hw: the txe hardware structure
81  * @offset: register offset
82  *
83  * Reads 32bit data from the SeC BAR and shout loud if aliveness is not set
84  *
85  * Return: register value
86  */
87 static inline u32 mei_txe_sec_reg_read(struct mei_txe_hw *hw,
88 				unsigned long offset)
89 {
90 	WARN(!hw->aliveness, "sec read: aliveness not asserted\n");
91 	return mei_txe_sec_reg_read_silent(hw, offset);
92 }
93 /**
94  * mei_txe_sec_reg_write_silent - Writes 32bit data to the SeC BAR
95  *   doesn't check for aliveness
96  *
97  * @hw: the txe hardware structure
98  * @offset: register offset
99  * @value: value to write
100  *
101  * Doesn't check for aliveness while writes 32bit data from to the SeC BAR
102  */
103 static inline void mei_txe_sec_reg_write_silent(struct mei_txe_hw *hw,
104 				unsigned long offset, u32 value)
105 {
106 	mei_txe_reg_write(hw->mem_addr[SEC_BAR], offset, value);
107 }
108 
109 /**
110  * mei_txe_sec_reg_write - Writes 32bit data to the SeC BAR
111  *
112  * @hw: the txe hardware structure
113  * @offset: register offset
114  * @value: value to write
115  *
116  * Writes 32bit data from the SeC BAR and shout loud if aliveness is not set
117  */
118 static inline void mei_txe_sec_reg_write(struct mei_txe_hw *hw,
119 				unsigned long offset, u32 value)
120 {
121 	WARN(!hw->aliveness, "sec write: aliveness not asserted\n");
122 	mei_txe_sec_reg_write_silent(hw, offset, value);
123 }
124 /**
125  * mei_txe_br_reg_read - Reads 32bit data from the Bridge BAR
126  *
127  * @hw: the txe hardware structure
128  * @offset: offset from which to read the data
129  *
130  * Return: the byte read.
131  */
132 static inline u32 mei_txe_br_reg_read(struct mei_txe_hw *hw,
133 				unsigned long offset)
134 {
135 	return mei_txe_reg_read(hw->mem_addr[BRIDGE_BAR], offset);
136 }
137 
138 /**
139  * mei_txe_br_reg_write - Writes 32bit data to the Bridge BAR
140  *
141  * @hw: the txe hardware structure
142  * @offset: offset from which to write the data
143  * @value: the byte to write
144  */
145 static inline void mei_txe_br_reg_write(struct mei_txe_hw *hw,
146 				unsigned long offset, u32 value)
147 {
148 	mei_txe_reg_write(hw->mem_addr[BRIDGE_BAR], offset, value);
149 }
150 
151 /**
152  * mei_txe_aliveness_set - request for aliveness change
153  *
154  * @dev: the device structure
155  * @req: requested aliveness value
156  *
157  * Request for aliveness change and returns true if the change is
158  *   really needed and false if aliveness is already
159  *   in the requested state
160  *
161  * Locking: called under "dev->device_lock" lock
162  *
163  * Return: true if request was send
164  */
165 static bool mei_txe_aliveness_set(struct mei_device *dev, u32 req)
166 {
167 
168 	struct mei_txe_hw *hw = to_txe_hw(dev);
169 	bool do_req = hw->aliveness != req;
170 
171 	dev_dbg(dev->dev, "Aliveness current=%d request=%d\n",
172 				hw->aliveness, req);
173 	if (do_req) {
174 		dev->pg_event = MEI_PG_EVENT_WAIT;
175 		mei_txe_br_reg_write(hw, SICR_HOST_ALIVENESS_REQ_REG, req);
176 	}
177 	return do_req;
178 }
179 
180 
181 /**
182  * mei_txe_aliveness_req_get - get aliveness requested register value
183  *
184  * @dev: the device structure
185  *
186  * Extract HICR_HOST_ALIVENESS_RESP_ACK bit from
187  * from HICR_HOST_ALIVENESS_REQ register value
188  *
189  * Return: SICR_HOST_ALIVENESS_REQ_REQUESTED bit value
190  */
191 static u32 mei_txe_aliveness_req_get(struct mei_device *dev)
192 {
193 	struct mei_txe_hw *hw = to_txe_hw(dev);
194 	u32 reg;
195 
196 	reg = mei_txe_br_reg_read(hw, SICR_HOST_ALIVENESS_REQ_REG);
197 	return reg & SICR_HOST_ALIVENESS_REQ_REQUESTED;
198 }
199 
200 /**
201  * mei_txe_aliveness_get - get aliveness response register value
202  *
203  * @dev: the device structure
204  *
205  * Return: HICR_HOST_ALIVENESS_RESP_ACK bit from HICR_HOST_ALIVENESS_RESP
206  *         register
207  */
208 static u32 mei_txe_aliveness_get(struct mei_device *dev)
209 {
210 	struct mei_txe_hw *hw = to_txe_hw(dev);
211 	u32 reg;
212 
213 	reg = mei_txe_br_reg_read(hw, HICR_HOST_ALIVENESS_RESP_REG);
214 	return reg & HICR_HOST_ALIVENESS_RESP_ACK;
215 }
216 
217 /**
218  * mei_txe_aliveness_poll - waits for aliveness to settle
219  *
220  * @dev: the device structure
221  * @expected: expected aliveness value
222  *
223  * Polls for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
224  *
225  * Return: 0 if the expected value was received, -ETIME otherwise
226  */
227 static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
228 {
229 	struct mei_txe_hw *hw = to_txe_hw(dev);
230 	ktime_t stop, start;
231 
232 	start = ktime_get();
233 	stop = ktime_add(start, ms_to_ktime(SEC_ALIVENESS_WAIT_TIMEOUT));
234 	do {
235 		hw->aliveness = mei_txe_aliveness_get(dev);
236 		if (hw->aliveness == expected) {
237 			dev->pg_event = MEI_PG_EVENT_IDLE;
238 			dev_dbg(dev->dev, "aliveness settled after %lld usecs\n",
239 				ktime_to_us(ktime_sub(ktime_get(), start)));
240 			return 0;
241 		}
242 		usleep_range(20, 50);
243 	} while (ktime_before(ktime_get(), stop));
244 
245 	dev->pg_event = MEI_PG_EVENT_IDLE;
246 	dev_err(dev->dev, "aliveness timed out\n");
247 	return -ETIME;
248 }
249 
250 /**
251  * mei_txe_aliveness_wait - waits for aliveness to settle
252  *
253  * @dev: the device structure
254  * @expected: expected aliveness value
255  *
256  * Waits for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
257  *
258  * Return: 0 on success and < 0 otherwise
259  */
260 static int mei_txe_aliveness_wait(struct mei_device *dev, u32 expected)
261 {
262 	struct mei_txe_hw *hw = to_txe_hw(dev);
263 	const unsigned long timeout =
264 			msecs_to_jiffies(SEC_ALIVENESS_WAIT_TIMEOUT);
265 	long err;
266 	int ret;
267 
268 	hw->aliveness = mei_txe_aliveness_get(dev);
269 	if (hw->aliveness == expected)
270 		return 0;
271 
272 	mutex_unlock(&dev->device_lock);
273 	err = wait_event_timeout(hw->wait_aliveness_resp,
274 			dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
275 	mutex_lock(&dev->device_lock);
276 
277 	hw->aliveness = mei_txe_aliveness_get(dev);
278 	ret = hw->aliveness == expected ? 0 : -ETIME;
279 
280 	if (ret)
281 		dev_warn(dev->dev, "aliveness timed out = %ld aliveness = %d event = %d\n",
282 			err, hw->aliveness, dev->pg_event);
283 	else
284 		dev_dbg(dev->dev, "aliveness settled after = %d msec aliveness = %d event = %d\n",
285 			jiffies_to_msecs(timeout - err),
286 			hw->aliveness, dev->pg_event);
287 
288 	dev->pg_event = MEI_PG_EVENT_IDLE;
289 	return ret;
290 }
291 
292 /**
293  * mei_txe_aliveness_set_sync - sets an wait for aliveness to complete
294  *
295  * @dev: the device structure
296  * @req: requested aliveness value
297  *
298  * Return: 0 on success and < 0 otherwise
299  */
300 int mei_txe_aliveness_set_sync(struct mei_device *dev, u32 req)
301 {
302 	if (mei_txe_aliveness_set(dev, req))
303 		return mei_txe_aliveness_wait(dev, req);
304 	return 0;
305 }
306 
307 /**
308  * mei_txe_pg_in_transition - is device now in pg transition
309  *
310  * @dev: the device structure
311  *
312  * Return: true if in pg transition, false otherwise
313  */
314 static bool mei_txe_pg_in_transition(struct mei_device *dev)
315 {
316 	return dev->pg_event == MEI_PG_EVENT_WAIT;
317 }
318 
319 /**
320  * mei_txe_pg_is_enabled - detect if PG is supported by HW
321  *
322  * @dev: the device structure
323  *
324  * Return: true is pg supported, false otherwise
325  */
326 static bool mei_txe_pg_is_enabled(struct mei_device *dev)
327 {
328 	return true;
329 }
330 
331 /**
332  * mei_txe_pg_state  - translate aliveness register value
333  *   to the mei power gating state
334  *
335  * @dev: the device structure
336  *
337  * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
338  */
339 static inline enum mei_pg_state mei_txe_pg_state(struct mei_device *dev)
340 {
341 	struct mei_txe_hw *hw = to_txe_hw(dev);
342 
343 	return hw->aliveness ? MEI_PG_OFF : MEI_PG_ON;
344 }
345 
346 /**
347  * mei_txe_input_ready_interrupt_enable - sets the Input Ready Interrupt
348  *
349  * @dev: the device structure
350  */
351 static void mei_txe_input_ready_interrupt_enable(struct mei_device *dev)
352 {
353 	struct mei_txe_hw *hw = to_txe_hw(dev);
354 	u32 hintmsk;
355 	/* Enable the SEC_IPC_HOST_INT_MASK_IN_RDY interrupt */
356 	hintmsk = mei_txe_sec_reg_read(hw, SEC_IPC_HOST_INT_MASK_REG);
357 	hintmsk |= SEC_IPC_HOST_INT_MASK_IN_RDY;
358 	mei_txe_sec_reg_write(hw, SEC_IPC_HOST_INT_MASK_REG, hintmsk);
359 }
360 
361 /**
362  * mei_txe_input_doorbell_set - sets bit 0 in
363  *    SEC_IPC_INPUT_DOORBELL.IPC_INPUT_DOORBELL.
364  *
365  * @hw: the txe hardware structure
366  */
367 static void mei_txe_input_doorbell_set(struct mei_txe_hw *hw)
368 {
369 	/* Clear the interrupt cause */
370 	clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause);
371 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_DOORBELL_REG, 1);
372 }
373 
374 /**
375  * mei_txe_output_ready_set - Sets the SICR_SEC_IPC_OUTPUT_STATUS bit to 1
376  *
377  * @hw: the txe hardware structure
378  */
379 static void mei_txe_output_ready_set(struct mei_txe_hw *hw)
380 {
381 	mei_txe_br_reg_write(hw,
382 			SICR_SEC_IPC_OUTPUT_STATUS_REG,
383 			SEC_IPC_OUTPUT_STATUS_RDY);
384 }
385 
386 /**
387  * mei_txe_is_input_ready - check if TXE is ready for receiving data
388  *
389  * @dev: the device structure
390  *
391  * Return: true if INPUT STATUS READY bit is set
392  */
393 static bool mei_txe_is_input_ready(struct mei_device *dev)
394 {
395 	struct mei_txe_hw *hw = to_txe_hw(dev);
396 	u32 status;
397 
398 	status = mei_txe_sec_reg_read(hw, SEC_IPC_INPUT_STATUS_REG);
399 	return !!(SEC_IPC_INPUT_STATUS_RDY & status);
400 }
401 
402 /**
403  * mei_txe_intr_clear - clear all interrupts
404  *
405  * @dev: the device structure
406  */
407 static inline void mei_txe_intr_clear(struct mei_device *dev)
408 {
409 	struct mei_txe_hw *hw = to_txe_hw(dev);
410 
411 	mei_txe_sec_reg_write_silent(hw, SEC_IPC_HOST_INT_STATUS_REG,
412 		SEC_IPC_HOST_INT_STATUS_PENDING);
413 	mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_STS_MSK);
414 	mei_txe_br_reg_write(hw, HHISR_REG, IPC_HHIER_MSK);
415 }
416 
417 /**
418  * mei_txe_intr_disable - disable all interrupts
419  *
420  * @dev: the device structure
421  */
422 static void mei_txe_intr_disable(struct mei_device *dev)
423 {
424 	struct mei_txe_hw *hw = to_txe_hw(dev);
425 
426 	mei_txe_br_reg_write(hw, HHIER_REG, 0);
427 	mei_txe_br_reg_write(hw, HIER_REG, 0);
428 }
429 /**
430  * mei_txe_intr_enable - enable all interrupts
431  *
432  * @dev: the device structure
433  */
434 static void mei_txe_intr_enable(struct mei_device *dev)
435 {
436 	struct mei_txe_hw *hw = to_txe_hw(dev);
437 
438 	mei_txe_br_reg_write(hw, HHIER_REG, IPC_HHIER_MSK);
439 	mei_txe_br_reg_write(hw, HIER_REG, HIER_INT_EN_MSK);
440 }
441 
442 /**
443  * mei_txe_pending_interrupts - check if there are pending interrupts
444  *	only Aliveness, Input ready, and output doorbell are of relevance
445  *
446  * @dev: the device structure
447  *
448  * Checks if there are pending interrupts
449  * only Aliveness, Readiness, Input ready, and Output doorbell are relevant
450  *
451  * Return: true if there are pending interrupts
452  */
453 static bool mei_txe_pending_interrupts(struct mei_device *dev)
454 {
455 
456 	struct mei_txe_hw *hw = to_txe_hw(dev);
457 	bool ret = (hw->intr_cause & (TXE_INTR_READINESS |
458 				      TXE_INTR_ALIVENESS |
459 				      TXE_INTR_IN_READY  |
460 				      TXE_INTR_OUT_DB));
461 
462 	if (ret) {
463 		dev_dbg(dev->dev,
464 			"Pending Interrupts InReady=%01d Readiness=%01d, Aliveness=%01d, OutDoor=%01d\n",
465 			!!(hw->intr_cause & TXE_INTR_IN_READY),
466 			!!(hw->intr_cause & TXE_INTR_READINESS),
467 			!!(hw->intr_cause & TXE_INTR_ALIVENESS),
468 			!!(hw->intr_cause & TXE_INTR_OUT_DB));
469 	}
470 	return ret;
471 }
472 
473 /**
474  * mei_txe_input_payload_write - write a dword to the host buffer
475  *	at offset idx
476  *
477  * @dev: the device structure
478  * @idx: index in the host buffer
479  * @value: value
480  */
481 static void mei_txe_input_payload_write(struct mei_device *dev,
482 			unsigned long idx, u32 value)
483 {
484 	struct mei_txe_hw *hw = to_txe_hw(dev);
485 
486 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_PAYLOAD_REG +
487 			(idx * sizeof(u32)), value);
488 }
489 
490 /**
491  * mei_txe_out_data_read - read dword from the device buffer
492  *	at offset idx
493  *
494  * @dev: the device structure
495  * @idx: index in the device buffer
496  *
497  * Return: register value at index
498  */
499 static u32 mei_txe_out_data_read(const struct mei_device *dev,
500 					unsigned long idx)
501 {
502 	struct mei_txe_hw *hw = to_txe_hw(dev);
503 
504 	return mei_txe_br_reg_read(hw,
505 		BRIDGE_IPC_OUTPUT_PAYLOAD_REG + (idx * sizeof(u32)));
506 }
507 
508 /* Readiness */
509 
510 /**
511  * mei_txe_readiness_set_host_rdy - set host readiness bit
512  *
513  * @dev: the device structure
514  */
515 static void mei_txe_readiness_set_host_rdy(struct mei_device *dev)
516 {
517 	struct mei_txe_hw *hw = to_txe_hw(dev);
518 
519 	mei_txe_br_reg_write(hw,
520 		SICR_HOST_IPC_READINESS_REQ_REG,
521 		SICR_HOST_IPC_READINESS_HOST_RDY);
522 }
523 
524 /**
525  * mei_txe_readiness_clear - clear host readiness bit
526  *
527  * @dev: the device structure
528  */
529 static void mei_txe_readiness_clear(struct mei_device *dev)
530 {
531 	struct mei_txe_hw *hw = to_txe_hw(dev);
532 
533 	mei_txe_br_reg_write(hw, SICR_HOST_IPC_READINESS_REQ_REG,
534 				SICR_HOST_IPC_READINESS_RDY_CLR);
535 }
536 /**
537  * mei_txe_readiness_get - Reads and returns
538  *	the HICR_SEC_IPC_READINESS register value
539  *
540  * @dev: the device structure
541  *
542  * Return: the HICR_SEC_IPC_READINESS register value
543  */
544 static u32 mei_txe_readiness_get(struct mei_device *dev)
545 {
546 	struct mei_txe_hw *hw = to_txe_hw(dev);
547 
548 	return mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
549 }
550 
551 
552 /**
553  * mei_txe_readiness_is_sec_rdy - check readiness
554  *  for HICR_SEC_IPC_READINESS_SEC_RDY
555  *
556  * @readiness: cached readiness state
557  *
558  * Return: true if readiness bit is set
559  */
560 static inline bool mei_txe_readiness_is_sec_rdy(u32 readiness)
561 {
562 	return !!(readiness & HICR_SEC_IPC_READINESS_SEC_RDY);
563 }
564 
565 /**
566  * mei_txe_hw_is_ready - check if the hw is ready
567  *
568  * @dev: the device structure
569  *
570  * Return: true if sec is ready
571  */
572 static bool mei_txe_hw_is_ready(struct mei_device *dev)
573 {
574 	u32 readiness =  mei_txe_readiness_get(dev);
575 
576 	return mei_txe_readiness_is_sec_rdy(readiness);
577 }
578 
579 /**
580  * mei_txe_host_is_ready - check if the host is ready
581  *
582  * @dev: the device structure
583  *
584  * Return: true if host is ready
585  */
586 static inline bool mei_txe_host_is_ready(struct mei_device *dev)
587 {
588 	struct mei_txe_hw *hw = to_txe_hw(dev);
589 	u32 reg = mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
590 
591 	return !!(reg & HICR_SEC_IPC_READINESS_HOST_RDY);
592 }
593 
594 /**
595  * mei_txe_readiness_wait - wait till readiness settles
596  *
597  * @dev: the device structure
598  *
599  * Return: 0 on success and -ETIME on timeout
600  */
601 static int mei_txe_readiness_wait(struct mei_device *dev)
602 {
603 	if (mei_txe_hw_is_ready(dev))
604 		return 0;
605 
606 	mutex_unlock(&dev->device_lock);
607 	wait_event_timeout(dev->wait_hw_ready, dev->recvd_hw_ready,
608 			msecs_to_jiffies(SEC_RESET_WAIT_TIMEOUT));
609 	mutex_lock(&dev->device_lock);
610 	if (!dev->recvd_hw_ready) {
611 		dev_err(dev->dev, "wait for readiness failed\n");
612 		return -ETIME;
613 	}
614 
615 	dev->recvd_hw_ready = false;
616 	return 0;
617 }
618 
619 static const struct mei_fw_status mei_txe_fw_sts = {
620 	.count = 2,
621 	.status[0] = PCI_CFG_TXE_FW_STS0,
622 	.status[1] = PCI_CFG_TXE_FW_STS1
623 };
624 
625 /**
626  * mei_txe_fw_status - read fw status register from pci config space
627  *
628  * @dev: mei device
629  * @fw_status: fw status register values
630  *
631  * Return: 0 on success, error otherwise
632  */
633 static int mei_txe_fw_status(struct mei_device *dev,
634 			     struct mei_fw_status *fw_status)
635 {
636 	const struct mei_fw_status *fw_src = &mei_txe_fw_sts;
637 	struct pci_dev *pdev = to_pci_dev(dev->dev);
638 	int ret;
639 	int i;
640 
641 	if (!fw_status)
642 		return -EINVAL;
643 
644 	fw_status->count = fw_src->count;
645 	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
646 		ret = pci_read_config_dword(pdev, fw_src->status[i],
647 					    &fw_status->status[i]);
648 		trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HSF_X",
649 				       fw_src->status[i],
650 				       fw_status->status[i]);
651 		if (ret)
652 			return ret;
653 	}
654 
655 	return 0;
656 }
657 
658 /**
659  *  mei_txe_hw_config - configure hardware at the start of the devices
660  *
661  * @dev: the device structure
662  *
663  * Configure hardware at the start of the device should be done only
664  *   once at the device probe time
665  */
666 static void mei_txe_hw_config(struct mei_device *dev)
667 {
668 
669 	struct mei_txe_hw *hw = to_txe_hw(dev);
670 
671 	/* Doesn't change in runtime */
672 	dev->hbuf_depth = PAYLOAD_SIZE / 4;
673 
674 	hw->aliveness = mei_txe_aliveness_get(dev);
675 	hw->readiness = mei_txe_readiness_get(dev);
676 
677 	dev_dbg(dev->dev, "aliveness_resp = 0x%08x, readiness = 0x%08x.\n",
678 		hw->aliveness, hw->readiness);
679 }
680 
681 
682 /**
683  * mei_txe_write - writes a message to device.
684  *
685  * @dev: the device structure
686  * @header: header of message
687  * @buf: message buffer will be written
688  *
689  * Return: 0 if success, <0 - otherwise.
690  */
691 
692 static int mei_txe_write(struct mei_device *dev,
693 		struct mei_msg_hdr *header, unsigned char *buf)
694 {
695 	struct mei_txe_hw *hw = to_txe_hw(dev);
696 	unsigned long rem;
697 	unsigned long length;
698 	int slots = dev->hbuf_depth;
699 	u32 *reg_buf = (u32 *)buf;
700 	u32 dw_cnt;
701 	int i;
702 
703 	if (WARN_ON(!header || !buf))
704 		return -EINVAL;
705 
706 	length = header->length;
707 
708 	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(header));
709 
710 	dw_cnt = mei_data2slots(length);
711 	if (dw_cnt > slots)
712 		return -EMSGSIZE;
713 
714 	if (WARN(!hw->aliveness, "txe write: aliveness not asserted\n"))
715 		return -EAGAIN;
716 
717 	/* Enable Input Ready Interrupt. */
718 	mei_txe_input_ready_interrupt_enable(dev);
719 
720 	if (!mei_txe_is_input_ready(dev)) {
721 		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
722 
723 		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
724 		dev_err(dev->dev, "Input is not ready %s\n", fw_sts_str);
725 		return -EAGAIN;
726 	}
727 
728 	mei_txe_input_payload_write(dev, 0, *((u32 *)header));
729 
730 	for (i = 0; i < length / 4; i++)
731 		mei_txe_input_payload_write(dev, i + 1, reg_buf[i]);
732 
733 	rem = length & 0x3;
734 	if (rem > 0) {
735 		u32 reg = 0;
736 
737 		memcpy(&reg, &buf[length - rem], rem);
738 		mei_txe_input_payload_write(dev, i + 1, reg);
739 	}
740 
741 	/* after each write the whole buffer is consumed */
742 	hw->slots = 0;
743 
744 	/* Set Input-Doorbell */
745 	mei_txe_input_doorbell_set(hw);
746 
747 	return 0;
748 }
749 
750 /**
751  * mei_txe_hbuf_max_len - mimics the me hbuf circular buffer
752  *
753  * @dev: the device structure
754  *
755  * Return: the PAYLOAD_SIZE - 4
756  */
757 static size_t mei_txe_hbuf_max_len(const struct mei_device *dev)
758 {
759 	return PAYLOAD_SIZE - sizeof(struct mei_msg_hdr);
760 }
761 
762 /**
763  * mei_txe_hbuf_empty_slots - mimics the me hbuf circular buffer
764  *
765  * @dev: the device structure
766  *
767  * Return: always hbuf_depth
768  */
769 static int mei_txe_hbuf_empty_slots(struct mei_device *dev)
770 {
771 	struct mei_txe_hw *hw = to_txe_hw(dev);
772 
773 	return hw->slots;
774 }
775 
776 /**
777  * mei_txe_count_full_read_slots - mimics the me device circular buffer
778  *
779  * @dev: the device structure
780  *
781  * Return: always buffer size in dwords count
782  */
783 static int mei_txe_count_full_read_slots(struct mei_device *dev)
784 {
785 	/* read buffers has static size */
786 	return  PAYLOAD_SIZE / 4;
787 }
788 
789 /**
790  * mei_txe_read_hdr - read message header which is always in 4 first bytes
791  *
792  * @dev: the device structure
793  *
794  * Return: mei message header
795  */
796 
797 static u32 mei_txe_read_hdr(const struct mei_device *dev)
798 {
799 	return mei_txe_out_data_read(dev, 0);
800 }
801 /**
802  * mei_txe_read - reads a message from the txe device.
803  *
804  * @dev: the device structure
805  * @buf: message buffer will be written
806  * @len: message size will be read
807  *
808  * Return: -EINVAL on error wrong argument and 0 on success
809  */
810 static int mei_txe_read(struct mei_device *dev,
811 		unsigned char *buf, unsigned long len)
812 {
813 
814 	struct mei_txe_hw *hw = to_txe_hw(dev);
815 	u32 *reg_buf, reg;
816 	u32 rem;
817 	u32 i;
818 
819 	if (WARN_ON(!buf || !len))
820 		return -EINVAL;
821 
822 	reg_buf = (u32 *)buf;
823 	rem = len & 0x3;
824 
825 	dev_dbg(dev->dev, "buffer-length = %lu buf[0]0x%08X\n",
826 		len, mei_txe_out_data_read(dev, 0));
827 
828 	for (i = 0; i < len / 4; i++) {
829 		/* skip header: index starts from 1 */
830 		reg = mei_txe_out_data_read(dev, i + 1);
831 		dev_dbg(dev->dev, "buf[%d] = 0x%08X\n", i, reg);
832 		*reg_buf++ = reg;
833 	}
834 
835 	if (rem) {
836 		reg = mei_txe_out_data_read(dev, i + 1);
837 		memcpy(reg_buf, &reg, rem);
838 	}
839 
840 	mei_txe_output_ready_set(hw);
841 	return 0;
842 }
843 
844 /**
845  * mei_txe_hw_reset - resets host and fw.
846  *
847  * @dev: the device structure
848  * @intr_enable: if interrupt should be enabled after reset.
849  *
850  * Return: 0 on success and < 0 in case of error
851  */
852 static int mei_txe_hw_reset(struct mei_device *dev, bool intr_enable)
853 {
854 	struct mei_txe_hw *hw = to_txe_hw(dev);
855 
856 	u32 aliveness_req;
857 	/*
858 	 * read input doorbell to ensure consistency between  Bridge and SeC
859 	 * return value might be garbage return
860 	 */
861 	(void)mei_txe_sec_reg_read_silent(hw, SEC_IPC_INPUT_DOORBELL_REG);
862 
863 	aliveness_req = mei_txe_aliveness_req_get(dev);
864 	hw->aliveness = mei_txe_aliveness_get(dev);
865 
866 	/* Disable interrupts in this stage we will poll */
867 	mei_txe_intr_disable(dev);
868 
869 	/*
870 	 * If Aliveness Request and Aliveness Response are not equal then
871 	 * wait for them to be equal
872 	 * Since we might have interrupts disabled - poll for it
873 	 */
874 	if (aliveness_req != hw->aliveness)
875 		if (mei_txe_aliveness_poll(dev, aliveness_req) < 0) {
876 			dev_err(dev->dev, "wait for aliveness settle failed ... bailing out\n");
877 			return -EIO;
878 		}
879 
880 	/*
881 	 * If Aliveness Request and Aliveness Response are set then clear them
882 	 */
883 	if (aliveness_req) {
884 		mei_txe_aliveness_set(dev, 0);
885 		if (mei_txe_aliveness_poll(dev, 0) < 0) {
886 			dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
887 			return -EIO;
888 		}
889 	}
890 
891 	/*
892 	 * Set readiness RDY_CLR bit
893 	 */
894 	mei_txe_readiness_clear(dev);
895 
896 	return 0;
897 }
898 
899 /**
900  * mei_txe_hw_start - start the hardware after reset
901  *
902  * @dev: the device structure
903  *
904  * Return: 0 on success an error code otherwise
905  */
906 static int mei_txe_hw_start(struct mei_device *dev)
907 {
908 	struct mei_txe_hw *hw = to_txe_hw(dev);
909 	int ret;
910 
911 	u32 hisr;
912 
913 	/* bring back interrupts */
914 	mei_txe_intr_enable(dev);
915 
916 	ret = mei_txe_readiness_wait(dev);
917 	if (ret < 0) {
918 		dev_err(dev->dev, "waiting for readiness failed\n");
919 		return ret;
920 	}
921 
922 	/*
923 	 * If HISR.INT2_STS interrupt status bit is set then clear it.
924 	 */
925 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
926 	if (hisr & HISR_INT_2_STS)
927 		mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_2_STS);
928 
929 	/* Clear the interrupt cause of OutputDoorbell */
930 	clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause);
931 
932 	ret = mei_txe_aliveness_set_sync(dev, 1);
933 	if (ret < 0) {
934 		dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
935 		return ret;
936 	}
937 
938 	/* enable input ready interrupts:
939 	 * SEC_IPC_HOST_INT_MASK.IPC_INPUT_READY_INT_MASK
940 	 */
941 	mei_txe_input_ready_interrupt_enable(dev);
942 
943 
944 	/*  Set the SICR_SEC_IPC_OUTPUT_STATUS.IPC_OUTPUT_READY bit */
945 	mei_txe_output_ready_set(hw);
946 
947 	/* Set bit SICR_HOST_IPC_READINESS.HOST_RDY
948 	 */
949 	mei_txe_readiness_set_host_rdy(dev);
950 
951 	return 0;
952 }
953 
954 /**
955  * mei_txe_check_and_ack_intrs - translate multi BAR interrupt into
956  *  single bit mask and acknowledge the interrupts
957  *
958  * @dev: the device structure
959  * @do_ack: acknowledge interrupts
960  *
961  * Return: true if found interrupts to process.
962  */
963 static bool mei_txe_check_and_ack_intrs(struct mei_device *dev, bool do_ack)
964 {
965 	struct mei_txe_hw *hw = to_txe_hw(dev);
966 	u32 hisr;
967 	u32 hhisr;
968 	u32 ipc_isr;
969 	u32 aliveness;
970 	bool generated;
971 
972 	/* read interrupt registers */
973 	hhisr = mei_txe_br_reg_read(hw, HHISR_REG);
974 	generated = (hhisr & IPC_HHIER_MSK);
975 	if (!generated)
976 		goto out;
977 
978 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
979 
980 	aliveness = mei_txe_aliveness_get(dev);
981 	if (hhisr & IPC_HHIER_SEC && aliveness)
982 		ipc_isr = mei_txe_sec_reg_read_silent(hw,
983 				SEC_IPC_HOST_INT_STATUS_REG);
984 	else
985 		ipc_isr = 0;
986 
987 	generated = generated ||
988 		(hisr & HISR_INT_STS_MSK) ||
989 		(ipc_isr & SEC_IPC_HOST_INT_STATUS_PENDING);
990 
991 	if (generated && do_ack) {
992 		/* Save the interrupt causes */
993 		hw->intr_cause |= hisr & HISR_INT_STS_MSK;
994 		if (ipc_isr & SEC_IPC_HOST_INT_STATUS_IN_RDY)
995 			hw->intr_cause |= TXE_INTR_IN_READY;
996 
997 
998 		mei_txe_intr_disable(dev);
999 		/* Clear the interrupts in hierarchy:
1000 		 * IPC and Bridge, than the High Level */
1001 		mei_txe_sec_reg_write_silent(hw,
1002 			SEC_IPC_HOST_INT_STATUS_REG, ipc_isr);
1003 		mei_txe_br_reg_write(hw, HISR_REG, hisr);
1004 		mei_txe_br_reg_write(hw, HHISR_REG, hhisr);
1005 	}
1006 
1007 out:
1008 	return generated;
1009 }
1010 
1011 /**
1012  * mei_txe_irq_quick_handler - The ISR of the MEI device
1013  *
1014  * @irq: The irq number
1015  * @dev_id: pointer to the device structure
1016  *
1017  * Return: IRQ_WAKE_THREAD if interrupt is designed for the device
1018  *         IRQ_NONE otherwise
1019  */
1020 irqreturn_t mei_txe_irq_quick_handler(int irq, void *dev_id)
1021 {
1022 	struct mei_device *dev = dev_id;
1023 
1024 	if (mei_txe_check_and_ack_intrs(dev, true))
1025 		return IRQ_WAKE_THREAD;
1026 	return IRQ_NONE;
1027 }
1028 
1029 
1030 /**
1031  * mei_txe_irq_thread_handler - txe interrupt thread
1032  *
1033  * @irq: The irq number
1034  * @dev_id: pointer to the device structure
1035  *
1036  * Return: IRQ_HANDLED
1037  */
1038 irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
1039 {
1040 	struct mei_device *dev = (struct mei_device *) dev_id;
1041 	struct mei_txe_hw *hw = to_txe_hw(dev);
1042 	struct mei_cl_cb complete_list;
1043 	s32 slots;
1044 	int rets = 0;
1045 
1046 	dev_dbg(dev->dev, "irq thread: Interrupt Registers HHISR|HISR|SEC=%02X|%04X|%02X\n",
1047 		mei_txe_br_reg_read(hw, HHISR_REG),
1048 		mei_txe_br_reg_read(hw, HISR_REG),
1049 		mei_txe_sec_reg_read_silent(hw, SEC_IPC_HOST_INT_STATUS_REG));
1050 
1051 
1052 	/* initialize our complete list */
1053 	mutex_lock(&dev->device_lock);
1054 	mei_io_list_init(&complete_list);
1055 
1056 	if (pci_dev_msi_enabled(to_pci_dev(dev->dev)))
1057 		mei_txe_check_and_ack_intrs(dev, true);
1058 
1059 	/* show irq events */
1060 	mei_txe_pending_interrupts(dev);
1061 
1062 	hw->aliveness = mei_txe_aliveness_get(dev);
1063 	hw->readiness = mei_txe_readiness_get(dev);
1064 
1065 	/* Readiness:
1066 	 * Detection of TXE driver going through reset
1067 	 * or TXE driver resetting the HECI interface.
1068 	 */
1069 	if (test_and_clear_bit(TXE_INTR_READINESS_BIT, &hw->intr_cause)) {
1070 		dev_dbg(dev->dev, "Readiness Interrupt was received...\n");
1071 
1072 		/* Check if SeC is going through reset */
1073 		if (mei_txe_readiness_is_sec_rdy(hw->readiness)) {
1074 			dev_dbg(dev->dev, "we need to start the dev.\n");
1075 			dev->recvd_hw_ready = true;
1076 		} else {
1077 			dev->recvd_hw_ready = false;
1078 			if (dev->dev_state != MEI_DEV_RESETTING) {
1079 
1080 				dev_warn(dev->dev, "FW not ready: resetting.\n");
1081 				schedule_work(&dev->reset_work);
1082 				goto end;
1083 
1084 			}
1085 		}
1086 		wake_up(&dev->wait_hw_ready);
1087 	}
1088 
1089 	/************************************************************/
1090 	/* Check interrupt cause:
1091 	 * Aliveness: Detection of SeC acknowledge of host request that
1092 	 * it remain alive or host cancellation of that request.
1093 	 */
1094 
1095 	if (test_and_clear_bit(TXE_INTR_ALIVENESS_BIT, &hw->intr_cause)) {
1096 		/* Clear the interrupt cause */
1097 		dev_dbg(dev->dev,
1098 			"Aliveness Interrupt: Status: %d\n", hw->aliveness);
1099 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
1100 		if (waitqueue_active(&hw->wait_aliveness_resp))
1101 			wake_up(&hw->wait_aliveness_resp);
1102 	}
1103 
1104 
1105 	/* Output Doorbell:
1106 	 * Detection of SeC having sent output to host
1107 	 */
1108 	slots = mei_count_full_read_slots(dev);
1109 	if (test_and_clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause)) {
1110 		/* Read from TXE */
1111 		rets = mei_irq_read_handler(dev, &complete_list, &slots);
1112 		if (rets && dev->dev_state != MEI_DEV_RESETTING) {
1113 			dev_err(dev->dev,
1114 				"mei_irq_read_handler ret = %d.\n", rets);
1115 
1116 			schedule_work(&dev->reset_work);
1117 			goto end;
1118 		}
1119 	}
1120 	/* Input Ready: Detection if host can write to SeC */
1121 	if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause)) {
1122 		dev->hbuf_is_ready = true;
1123 		hw->slots = dev->hbuf_depth;
1124 	}
1125 
1126 	if (hw->aliveness && dev->hbuf_is_ready) {
1127 		/* get the real register value */
1128 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1129 		rets = mei_irq_write_handler(dev, &complete_list);
1130 		if (rets && rets != -EMSGSIZE)
1131 			dev_err(dev->dev, "mei_irq_write_handler ret = %d.\n",
1132 				rets);
1133 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1134 	}
1135 
1136 	mei_irq_compl_handler(dev, &complete_list);
1137 
1138 end:
1139 	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
1140 
1141 	mutex_unlock(&dev->device_lock);
1142 
1143 	mei_enable_interrupts(dev);
1144 	return IRQ_HANDLED;
1145 }
1146 
1147 static const struct mei_hw_ops mei_txe_hw_ops = {
1148 
1149 	.host_is_ready = mei_txe_host_is_ready,
1150 
1151 	.fw_status = mei_txe_fw_status,
1152 	.pg_state = mei_txe_pg_state,
1153 
1154 	.hw_is_ready = mei_txe_hw_is_ready,
1155 	.hw_reset = mei_txe_hw_reset,
1156 	.hw_config = mei_txe_hw_config,
1157 	.hw_start = mei_txe_hw_start,
1158 
1159 	.pg_in_transition = mei_txe_pg_in_transition,
1160 	.pg_is_enabled = mei_txe_pg_is_enabled,
1161 
1162 	.intr_clear = mei_txe_intr_clear,
1163 	.intr_enable = mei_txe_intr_enable,
1164 	.intr_disable = mei_txe_intr_disable,
1165 
1166 	.hbuf_free_slots = mei_txe_hbuf_empty_slots,
1167 	.hbuf_is_ready = mei_txe_is_input_ready,
1168 	.hbuf_max_len = mei_txe_hbuf_max_len,
1169 
1170 	.write = mei_txe_write,
1171 
1172 	.rdbuf_full_slots = mei_txe_count_full_read_slots,
1173 	.read_hdr = mei_txe_read_hdr,
1174 
1175 	.read = mei_txe_read,
1176 
1177 };
1178 
1179 /**
1180  * mei_txe_dev_init - allocates and initializes txe hardware specific structure
1181  *
1182  * @pdev: pci device
1183  *
1184  * Return: struct mei_device * on success or NULL
1185  */
1186 struct mei_device *mei_txe_dev_init(struct pci_dev *pdev)
1187 {
1188 	struct mei_device *dev;
1189 	struct mei_txe_hw *hw;
1190 
1191 	dev = kzalloc(sizeof(struct mei_device) +
1192 			 sizeof(struct mei_txe_hw), GFP_KERNEL);
1193 	if (!dev)
1194 		return NULL;
1195 
1196 	mei_device_init(dev, &pdev->dev, &mei_txe_hw_ops);
1197 
1198 	hw = to_txe_hw(dev);
1199 
1200 	init_waitqueue_head(&hw->wait_aliveness_resp);
1201 
1202 	return dev;
1203 }
1204 
1205 /**
1206  * mei_txe_setup_satt2 - SATT2 configuration for DMA support.
1207  *
1208  * @dev:   the device structure
1209  * @addr:  physical address start of the range
1210  * @range: physical range size
1211  *
1212  * Return: 0 on success an error code otherwise
1213  */
1214 int mei_txe_setup_satt2(struct mei_device *dev, phys_addr_t addr, u32 range)
1215 {
1216 	struct mei_txe_hw *hw = to_txe_hw(dev);
1217 
1218 	u32 lo32 = lower_32_bits(addr);
1219 	u32 hi32 = upper_32_bits(addr);
1220 	u32 ctrl;
1221 
1222 	/* SATT is limited to 36 Bits */
1223 	if (hi32 & ~0xF)
1224 		return -EINVAL;
1225 
1226 	/* SATT has to be 16Byte aligned */
1227 	if (lo32 & 0xF)
1228 		return -EINVAL;
1229 
1230 	/* SATT range has to be 4Bytes aligned */
1231 	if (range & 0x4)
1232 		return -EINVAL;
1233 
1234 	/* SATT is limited to 32 MB range*/
1235 	if (range > SATT_RANGE_MAX)
1236 		return -EINVAL;
1237 
1238 	ctrl = SATT2_CTRL_VALID_MSK;
1239 	ctrl |= hi32  << SATT2_CTRL_BR_BASE_ADDR_REG_SHIFT;
1240 
1241 	mei_txe_br_reg_write(hw, SATT2_SAP_SIZE_REG, range);
1242 	mei_txe_br_reg_write(hw, SATT2_BRG_BA_LSB_REG, lo32);
1243 	mei_txe_br_reg_write(hw, SATT2_CTRL_REG, ctrl);
1244 	dev_dbg(dev->dev, "SATT2: SAP_SIZE_OFFSET=0x%08X, BRG_BA_LSB_OFFSET=0x%08X, CTRL_OFFSET=0x%08X\n",
1245 		range, lo32, ctrl);
1246 
1247 	return 0;
1248 }
1249