xref: /openbmc/linux/drivers/misc/mei/hw-txe.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2013-2020, Intel Corporation. All rights reserved.
4  * Intel Management Engine Interface (Intel MEI) Linux driver
5  */
6 
7 #include <linux/pci.h>
8 #include <linux/jiffies.h>
9 #include <linux/ktime.h>
10 #include <linux/delay.h>
11 #include <linux/kthread.h>
12 #include <linux/interrupt.h>
13 #include <linux/pm_runtime.h>
14 
15 #include <linux/mei.h>
16 
17 #include "mei_dev.h"
18 #include "hw-txe.h"
19 #include "client.h"
20 #include "hbm.h"
21 
22 #include "mei-trace.h"
23 
24 #define TXE_HBUF_DEPTH (PAYLOAD_SIZE / MEI_SLOT_SIZE)
25 
26 /**
27  * mei_txe_reg_read - Reads 32bit data from the txe device
28  *
29  * @base_addr: registers base address
30  * @offset: register offset
31  *
32  * Return: register value
33  */
34 static inline u32 mei_txe_reg_read(void __iomem *base_addr,
35 					unsigned long offset)
36 {
37 	return ioread32(base_addr + offset);
38 }
39 
40 /**
41  * mei_txe_reg_write - Writes 32bit data to the txe device
42  *
43  * @base_addr: registers base address
44  * @offset: register offset
45  * @value: the value to write
46  */
47 static inline void mei_txe_reg_write(void __iomem *base_addr,
48 				unsigned long offset, u32 value)
49 {
50 	iowrite32(value, base_addr + offset);
51 }
52 
53 /**
54  * mei_txe_sec_reg_read_silent - Reads 32bit data from the SeC BAR
55  *
56  * @hw: the txe hardware structure
57  * @offset: register offset
58  *
59  * Doesn't check for aliveness while Reads 32bit data from the SeC BAR
60  *
61  * Return: register value
62  */
63 static inline u32 mei_txe_sec_reg_read_silent(struct mei_txe_hw *hw,
64 				unsigned long offset)
65 {
66 	return mei_txe_reg_read(hw->mem_addr[SEC_BAR], offset);
67 }
68 
69 /**
70  * mei_txe_sec_reg_read - Reads 32bit data from the SeC BAR
71  *
72  * @hw: the txe hardware structure
73  * @offset: register offset
74  *
75  * Reads 32bit data from the SeC BAR and shout loud if aliveness is not set
76  *
77  * Return: register value
78  */
79 static inline u32 mei_txe_sec_reg_read(struct mei_txe_hw *hw,
80 				unsigned long offset)
81 {
82 	WARN(!hw->aliveness, "sec read: aliveness not asserted\n");
83 	return mei_txe_sec_reg_read_silent(hw, offset);
84 }
85 /**
86  * mei_txe_sec_reg_write_silent - Writes 32bit data to the SeC BAR
87  *   doesn't check for aliveness
88  *
89  * @hw: the txe hardware structure
90  * @offset: register offset
91  * @value: value to write
92  *
93  * Doesn't check for aliveness while writes 32bit data from to the SeC BAR
94  */
95 static inline void mei_txe_sec_reg_write_silent(struct mei_txe_hw *hw,
96 				unsigned long offset, u32 value)
97 {
98 	mei_txe_reg_write(hw->mem_addr[SEC_BAR], offset, value);
99 }
100 
101 /**
102  * mei_txe_sec_reg_write - Writes 32bit data to the SeC BAR
103  *
104  * @hw: the txe hardware structure
105  * @offset: register offset
106  * @value: value to write
107  *
108  * Writes 32bit data from the SeC BAR and shout loud if aliveness is not set
109  */
110 static inline void mei_txe_sec_reg_write(struct mei_txe_hw *hw,
111 				unsigned long offset, u32 value)
112 {
113 	WARN(!hw->aliveness, "sec write: aliveness not asserted\n");
114 	mei_txe_sec_reg_write_silent(hw, offset, value);
115 }
116 /**
117  * mei_txe_br_reg_read - Reads 32bit data from the Bridge BAR
118  *
119  * @hw: the txe hardware structure
120  * @offset: offset from which to read the data
121  *
122  * Return: the byte read.
123  */
124 static inline u32 mei_txe_br_reg_read(struct mei_txe_hw *hw,
125 				unsigned long offset)
126 {
127 	return mei_txe_reg_read(hw->mem_addr[BRIDGE_BAR], offset);
128 }
129 
130 /**
131  * mei_txe_br_reg_write - Writes 32bit data to the Bridge BAR
132  *
133  * @hw: the txe hardware structure
134  * @offset: offset from which to write the data
135  * @value: the byte to write
136  */
137 static inline void mei_txe_br_reg_write(struct mei_txe_hw *hw,
138 				unsigned long offset, u32 value)
139 {
140 	mei_txe_reg_write(hw->mem_addr[BRIDGE_BAR], offset, value);
141 }
142 
143 /**
144  * mei_txe_aliveness_set - request for aliveness change
145  *
146  * @dev: the device structure
147  * @req: requested aliveness value
148  *
149  * Request for aliveness change and returns true if the change is
150  *   really needed and false if aliveness is already
151  *   in the requested state
152  *
153  * Locking: called under "dev->device_lock" lock
154  *
155  * Return: true if request was send
156  */
157 static bool mei_txe_aliveness_set(struct mei_device *dev, u32 req)
158 {
159 
160 	struct mei_txe_hw *hw = to_txe_hw(dev);
161 	bool do_req = hw->aliveness != req;
162 
163 	dev_dbg(dev->dev, "Aliveness current=%d request=%d\n",
164 				hw->aliveness, req);
165 	if (do_req) {
166 		dev->pg_event = MEI_PG_EVENT_WAIT;
167 		mei_txe_br_reg_write(hw, SICR_HOST_ALIVENESS_REQ_REG, req);
168 	}
169 	return do_req;
170 }
171 
172 
173 /**
174  * mei_txe_aliveness_req_get - get aliveness requested register value
175  *
176  * @dev: the device structure
177  *
178  * Extract HICR_HOST_ALIVENESS_RESP_ACK bit from
179  * from HICR_HOST_ALIVENESS_REQ register value
180  *
181  * Return: SICR_HOST_ALIVENESS_REQ_REQUESTED bit value
182  */
183 static u32 mei_txe_aliveness_req_get(struct mei_device *dev)
184 {
185 	struct mei_txe_hw *hw = to_txe_hw(dev);
186 	u32 reg;
187 
188 	reg = mei_txe_br_reg_read(hw, SICR_HOST_ALIVENESS_REQ_REG);
189 	return reg & SICR_HOST_ALIVENESS_REQ_REQUESTED;
190 }
191 
192 /**
193  * mei_txe_aliveness_get - get aliveness response register value
194  *
195  * @dev: the device structure
196  *
197  * Return: HICR_HOST_ALIVENESS_RESP_ACK bit from HICR_HOST_ALIVENESS_RESP
198  *         register
199  */
200 static u32 mei_txe_aliveness_get(struct mei_device *dev)
201 {
202 	struct mei_txe_hw *hw = to_txe_hw(dev);
203 	u32 reg;
204 
205 	reg = mei_txe_br_reg_read(hw, HICR_HOST_ALIVENESS_RESP_REG);
206 	return reg & HICR_HOST_ALIVENESS_RESP_ACK;
207 }
208 
209 /**
210  * mei_txe_aliveness_poll - waits for aliveness to settle
211  *
212  * @dev: the device structure
213  * @expected: expected aliveness value
214  *
215  * Polls for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
216  *
217  * Return: 0 if the expected value was received, -ETIME otherwise
218  */
219 static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
220 {
221 	struct mei_txe_hw *hw = to_txe_hw(dev);
222 	ktime_t stop, start;
223 
224 	start = ktime_get();
225 	stop = ktime_add(start, ms_to_ktime(SEC_ALIVENESS_WAIT_TIMEOUT));
226 	do {
227 		hw->aliveness = mei_txe_aliveness_get(dev);
228 		if (hw->aliveness == expected) {
229 			dev->pg_event = MEI_PG_EVENT_IDLE;
230 			dev_dbg(dev->dev, "aliveness settled after %lld usecs\n",
231 				ktime_to_us(ktime_sub(ktime_get(), start)));
232 			return 0;
233 		}
234 		usleep_range(20, 50);
235 	} while (ktime_before(ktime_get(), stop));
236 
237 	dev->pg_event = MEI_PG_EVENT_IDLE;
238 	dev_err(dev->dev, "aliveness timed out\n");
239 	return -ETIME;
240 }
241 
242 /**
243  * mei_txe_aliveness_wait - waits for aliveness to settle
244  *
245  * @dev: the device structure
246  * @expected: expected aliveness value
247  *
248  * Waits for HICR_HOST_ALIVENESS_RESP.ALIVENESS_RESP to be set
249  *
250  * Return: 0 on success and < 0 otherwise
251  */
252 static int mei_txe_aliveness_wait(struct mei_device *dev, u32 expected)
253 {
254 	struct mei_txe_hw *hw = to_txe_hw(dev);
255 	const unsigned long timeout =
256 			msecs_to_jiffies(SEC_ALIVENESS_WAIT_TIMEOUT);
257 	long err;
258 	int ret;
259 
260 	hw->aliveness = mei_txe_aliveness_get(dev);
261 	if (hw->aliveness == expected)
262 		return 0;
263 
264 	mutex_unlock(&dev->device_lock);
265 	err = wait_event_timeout(hw->wait_aliveness_resp,
266 			dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
267 	mutex_lock(&dev->device_lock);
268 
269 	hw->aliveness = mei_txe_aliveness_get(dev);
270 	ret = hw->aliveness == expected ? 0 : -ETIME;
271 
272 	if (ret)
273 		dev_warn(dev->dev, "aliveness timed out = %ld aliveness = %d event = %d\n",
274 			err, hw->aliveness, dev->pg_event);
275 	else
276 		dev_dbg(dev->dev, "aliveness settled after = %d msec aliveness = %d event = %d\n",
277 			jiffies_to_msecs(timeout - err),
278 			hw->aliveness, dev->pg_event);
279 
280 	dev->pg_event = MEI_PG_EVENT_IDLE;
281 	return ret;
282 }
283 
284 /**
285  * mei_txe_aliveness_set_sync - sets an wait for aliveness to complete
286  *
287  * @dev: the device structure
288  * @req: requested aliveness value
289  *
290  * Return: 0 on success and < 0 otherwise
291  */
292 int mei_txe_aliveness_set_sync(struct mei_device *dev, u32 req)
293 {
294 	if (mei_txe_aliveness_set(dev, req))
295 		return mei_txe_aliveness_wait(dev, req);
296 	return 0;
297 }
298 
299 /**
300  * mei_txe_pg_in_transition - is device now in pg transition
301  *
302  * @dev: the device structure
303  *
304  * Return: true if in pg transition, false otherwise
305  */
306 static bool mei_txe_pg_in_transition(struct mei_device *dev)
307 {
308 	return dev->pg_event == MEI_PG_EVENT_WAIT;
309 }
310 
311 /**
312  * mei_txe_pg_is_enabled - detect if PG is supported by HW
313  *
314  * @dev: the device structure
315  *
316  * Return: true is pg supported, false otherwise
317  */
318 static bool mei_txe_pg_is_enabled(struct mei_device *dev)
319 {
320 	return true;
321 }
322 
323 /**
324  * mei_txe_pg_state  - translate aliveness register value
325  *   to the mei power gating state
326  *
327  * @dev: the device structure
328  *
329  * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
330  */
331 static inline enum mei_pg_state mei_txe_pg_state(struct mei_device *dev)
332 {
333 	struct mei_txe_hw *hw = to_txe_hw(dev);
334 
335 	return hw->aliveness ? MEI_PG_OFF : MEI_PG_ON;
336 }
337 
338 /**
339  * mei_txe_input_ready_interrupt_enable - sets the Input Ready Interrupt
340  *
341  * @dev: the device structure
342  */
343 static void mei_txe_input_ready_interrupt_enable(struct mei_device *dev)
344 {
345 	struct mei_txe_hw *hw = to_txe_hw(dev);
346 	u32 hintmsk;
347 	/* Enable the SEC_IPC_HOST_INT_MASK_IN_RDY interrupt */
348 	hintmsk = mei_txe_sec_reg_read(hw, SEC_IPC_HOST_INT_MASK_REG);
349 	hintmsk |= SEC_IPC_HOST_INT_MASK_IN_RDY;
350 	mei_txe_sec_reg_write(hw, SEC_IPC_HOST_INT_MASK_REG, hintmsk);
351 }
352 
353 /**
354  * mei_txe_input_doorbell_set - sets bit 0 in
355  *    SEC_IPC_INPUT_DOORBELL.IPC_INPUT_DOORBELL.
356  *
357  * @hw: the txe hardware structure
358  */
359 static void mei_txe_input_doorbell_set(struct mei_txe_hw *hw)
360 {
361 	/* Clear the interrupt cause */
362 	clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause);
363 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_DOORBELL_REG, 1);
364 }
365 
366 /**
367  * mei_txe_output_ready_set - Sets the SICR_SEC_IPC_OUTPUT_STATUS bit to 1
368  *
369  * @hw: the txe hardware structure
370  */
371 static void mei_txe_output_ready_set(struct mei_txe_hw *hw)
372 {
373 	mei_txe_br_reg_write(hw,
374 			SICR_SEC_IPC_OUTPUT_STATUS_REG,
375 			SEC_IPC_OUTPUT_STATUS_RDY);
376 }
377 
378 /**
379  * mei_txe_is_input_ready - check if TXE is ready for receiving data
380  *
381  * @dev: the device structure
382  *
383  * Return: true if INPUT STATUS READY bit is set
384  */
385 static bool mei_txe_is_input_ready(struct mei_device *dev)
386 {
387 	struct mei_txe_hw *hw = to_txe_hw(dev);
388 	u32 status;
389 
390 	status = mei_txe_sec_reg_read(hw, SEC_IPC_INPUT_STATUS_REG);
391 	return !!(SEC_IPC_INPUT_STATUS_RDY & status);
392 }
393 
394 /**
395  * mei_txe_intr_clear - clear all interrupts
396  *
397  * @dev: the device structure
398  */
399 static inline void mei_txe_intr_clear(struct mei_device *dev)
400 {
401 	struct mei_txe_hw *hw = to_txe_hw(dev);
402 
403 	mei_txe_sec_reg_write_silent(hw, SEC_IPC_HOST_INT_STATUS_REG,
404 		SEC_IPC_HOST_INT_STATUS_PENDING);
405 	mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_STS_MSK);
406 	mei_txe_br_reg_write(hw, HHISR_REG, IPC_HHIER_MSK);
407 }
408 
409 /**
410  * mei_txe_intr_disable - disable all interrupts
411  *
412  * @dev: the device structure
413  */
414 static void mei_txe_intr_disable(struct mei_device *dev)
415 {
416 	struct mei_txe_hw *hw = to_txe_hw(dev);
417 
418 	mei_txe_br_reg_write(hw, HHIER_REG, 0);
419 	mei_txe_br_reg_write(hw, HIER_REG, 0);
420 }
421 /**
422  * mei_txe_intr_enable - enable all interrupts
423  *
424  * @dev: the device structure
425  */
426 static void mei_txe_intr_enable(struct mei_device *dev)
427 {
428 	struct mei_txe_hw *hw = to_txe_hw(dev);
429 
430 	mei_txe_br_reg_write(hw, HHIER_REG, IPC_HHIER_MSK);
431 	mei_txe_br_reg_write(hw, HIER_REG, HIER_INT_EN_MSK);
432 }
433 
434 /**
435  * mei_txe_synchronize_irq - wait for pending IRQ handlers
436  *
437  * @dev: the device structure
438  */
439 static void mei_txe_synchronize_irq(struct mei_device *dev)
440 {
441 	struct pci_dev *pdev = to_pci_dev(dev->dev);
442 
443 	synchronize_irq(pdev->irq);
444 }
445 
446 /**
447  * mei_txe_pending_interrupts - check if there are pending interrupts
448  *	only Aliveness, Input ready, and output doorbell are of relevance
449  *
450  * @dev: the device structure
451  *
452  * Checks if there are pending interrupts
453  * only Aliveness, Readiness, Input ready, and Output doorbell are relevant
454  *
455  * Return: true if there are pending interrupts
456  */
457 static bool mei_txe_pending_interrupts(struct mei_device *dev)
458 {
459 
460 	struct mei_txe_hw *hw = to_txe_hw(dev);
461 	bool ret = (hw->intr_cause & (TXE_INTR_READINESS |
462 				      TXE_INTR_ALIVENESS |
463 				      TXE_INTR_IN_READY  |
464 				      TXE_INTR_OUT_DB));
465 
466 	if (ret) {
467 		dev_dbg(dev->dev,
468 			"Pending Interrupts InReady=%01d Readiness=%01d, Aliveness=%01d, OutDoor=%01d\n",
469 			!!(hw->intr_cause & TXE_INTR_IN_READY),
470 			!!(hw->intr_cause & TXE_INTR_READINESS),
471 			!!(hw->intr_cause & TXE_INTR_ALIVENESS),
472 			!!(hw->intr_cause & TXE_INTR_OUT_DB));
473 	}
474 	return ret;
475 }
476 
477 /**
478  * mei_txe_input_payload_write - write a dword to the host buffer
479  *	at offset idx
480  *
481  * @dev: the device structure
482  * @idx: index in the host buffer
483  * @value: value
484  */
485 static void mei_txe_input_payload_write(struct mei_device *dev,
486 			unsigned long idx, u32 value)
487 {
488 	struct mei_txe_hw *hw = to_txe_hw(dev);
489 
490 	mei_txe_sec_reg_write(hw, SEC_IPC_INPUT_PAYLOAD_REG +
491 			(idx * sizeof(u32)), value);
492 }
493 
494 /**
495  * mei_txe_out_data_read - read dword from the device buffer
496  *	at offset idx
497  *
498  * @dev: the device structure
499  * @idx: index in the device buffer
500  *
501  * Return: register value at index
502  */
503 static u32 mei_txe_out_data_read(const struct mei_device *dev,
504 					unsigned long idx)
505 {
506 	struct mei_txe_hw *hw = to_txe_hw(dev);
507 
508 	return mei_txe_br_reg_read(hw,
509 		BRIDGE_IPC_OUTPUT_PAYLOAD_REG + (idx * sizeof(u32)));
510 }
511 
512 /* Readiness */
513 
514 /**
515  * mei_txe_readiness_set_host_rdy - set host readiness bit
516  *
517  * @dev: the device structure
518  */
519 static void mei_txe_readiness_set_host_rdy(struct mei_device *dev)
520 {
521 	struct mei_txe_hw *hw = to_txe_hw(dev);
522 
523 	mei_txe_br_reg_write(hw,
524 		SICR_HOST_IPC_READINESS_REQ_REG,
525 		SICR_HOST_IPC_READINESS_HOST_RDY);
526 }
527 
528 /**
529  * mei_txe_readiness_clear - clear host readiness bit
530  *
531  * @dev: the device structure
532  */
533 static void mei_txe_readiness_clear(struct mei_device *dev)
534 {
535 	struct mei_txe_hw *hw = to_txe_hw(dev);
536 
537 	mei_txe_br_reg_write(hw, SICR_HOST_IPC_READINESS_REQ_REG,
538 				SICR_HOST_IPC_READINESS_RDY_CLR);
539 }
540 /**
541  * mei_txe_readiness_get - Reads and returns
542  *	the HICR_SEC_IPC_READINESS register value
543  *
544  * @dev: the device structure
545  *
546  * Return: the HICR_SEC_IPC_READINESS register value
547  */
548 static u32 mei_txe_readiness_get(struct mei_device *dev)
549 {
550 	struct mei_txe_hw *hw = to_txe_hw(dev);
551 
552 	return mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
553 }
554 
555 
556 /**
557  * mei_txe_readiness_is_sec_rdy - check readiness
558  *  for HICR_SEC_IPC_READINESS_SEC_RDY
559  *
560  * @readiness: cached readiness state
561  *
562  * Return: true if readiness bit is set
563  */
564 static inline bool mei_txe_readiness_is_sec_rdy(u32 readiness)
565 {
566 	return !!(readiness & HICR_SEC_IPC_READINESS_SEC_RDY);
567 }
568 
569 /**
570  * mei_txe_hw_is_ready - check if the hw is ready
571  *
572  * @dev: the device structure
573  *
574  * Return: true if sec is ready
575  */
576 static bool mei_txe_hw_is_ready(struct mei_device *dev)
577 {
578 	u32 readiness =  mei_txe_readiness_get(dev);
579 
580 	return mei_txe_readiness_is_sec_rdy(readiness);
581 }
582 
583 /**
584  * mei_txe_host_is_ready - check if the host is ready
585  *
586  * @dev: the device structure
587  *
588  * Return: true if host is ready
589  */
590 static inline bool mei_txe_host_is_ready(struct mei_device *dev)
591 {
592 	struct mei_txe_hw *hw = to_txe_hw(dev);
593 	u32 reg = mei_txe_br_reg_read(hw, HICR_SEC_IPC_READINESS_REG);
594 
595 	return !!(reg & HICR_SEC_IPC_READINESS_HOST_RDY);
596 }
597 
598 /**
599  * mei_txe_readiness_wait - wait till readiness settles
600  *
601  * @dev: the device structure
602  *
603  * Return: 0 on success and -ETIME on timeout
604  */
605 static int mei_txe_readiness_wait(struct mei_device *dev)
606 {
607 	if (mei_txe_hw_is_ready(dev))
608 		return 0;
609 
610 	mutex_unlock(&dev->device_lock);
611 	wait_event_timeout(dev->wait_hw_ready, dev->recvd_hw_ready,
612 			msecs_to_jiffies(SEC_RESET_WAIT_TIMEOUT));
613 	mutex_lock(&dev->device_lock);
614 	if (!dev->recvd_hw_ready) {
615 		dev_err(dev->dev, "wait for readiness failed\n");
616 		return -ETIME;
617 	}
618 
619 	dev->recvd_hw_ready = false;
620 	return 0;
621 }
622 
623 static const struct mei_fw_status mei_txe_fw_sts = {
624 	.count = 2,
625 	.status[0] = PCI_CFG_TXE_FW_STS0,
626 	.status[1] = PCI_CFG_TXE_FW_STS1
627 };
628 
629 /**
630  * mei_txe_fw_status - read fw status register from pci config space
631  *
632  * @dev: mei device
633  * @fw_status: fw status register values
634  *
635  * Return: 0 on success, error otherwise
636  */
637 static int mei_txe_fw_status(struct mei_device *dev,
638 			     struct mei_fw_status *fw_status)
639 {
640 	const struct mei_fw_status *fw_src = &mei_txe_fw_sts;
641 	struct pci_dev *pdev = to_pci_dev(dev->dev);
642 	int ret;
643 	int i;
644 
645 	if (!fw_status)
646 		return -EINVAL;
647 
648 	fw_status->count = fw_src->count;
649 	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
650 		ret = pci_read_config_dword(pdev, fw_src->status[i],
651 					    &fw_status->status[i]);
652 		trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HSF_X",
653 				       fw_src->status[i],
654 				       fw_status->status[i]);
655 		if (ret)
656 			return ret;
657 	}
658 
659 	return 0;
660 }
661 
662 /**
663  * mei_txe_hw_config - configure hardware at the start of the devices
664  *
665  * @dev: the device structure
666  *
667  * Configure hardware at the start of the device should be done only
668  *   once at the device probe time
669  *
670  * Return: always 0
671  */
672 static int mei_txe_hw_config(struct mei_device *dev)
673 {
674 
675 	struct mei_txe_hw *hw = to_txe_hw(dev);
676 
677 	hw->aliveness = mei_txe_aliveness_get(dev);
678 	hw->readiness = mei_txe_readiness_get(dev);
679 
680 	dev_dbg(dev->dev, "aliveness_resp = 0x%08x, readiness = 0x%08x.\n",
681 		hw->aliveness, hw->readiness);
682 
683 	return 0;
684 }
685 
686 /**
687  * mei_txe_write - writes a message to device.
688  *
689  * @dev: the device structure
690  * @hdr: header of message
691  * @hdr_len: header length in bytes - must multiplication of a slot (4bytes)
692  * @data: payload
693  * @data_len: paylead length in bytes
694  *
695  * Return: 0 if success, < 0 - otherwise.
696  */
697 static int mei_txe_write(struct mei_device *dev,
698 			 const void *hdr, size_t hdr_len,
699 			 const void *data, size_t data_len)
700 {
701 	struct mei_txe_hw *hw = to_txe_hw(dev);
702 	unsigned long rem;
703 	const u32 *reg_buf;
704 	u32 slots = TXE_HBUF_DEPTH;
705 	u32 dw_cnt;
706 	unsigned long i, j;
707 
708 	if (WARN_ON(!hdr || !data || hdr_len & 0x3))
709 		return -EINVAL;
710 
711 	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM((struct mei_msg_hdr *)hdr));
712 
713 	dw_cnt = mei_data2slots(hdr_len + data_len);
714 	if (dw_cnt > slots)
715 		return -EMSGSIZE;
716 
717 	if (WARN(!hw->aliveness, "txe write: aliveness not asserted\n"))
718 		return -EAGAIN;
719 
720 	/* Enable Input Ready Interrupt. */
721 	mei_txe_input_ready_interrupt_enable(dev);
722 
723 	if (!mei_txe_is_input_ready(dev)) {
724 		char fw_sts_str[MEI_FW_STATUS_STR_SZ];
725 
726 		mei_fw_status_str(dev, fw_sts_str, MEI_FW_STATUS_STR_SZ);
727 		dev_err(dev->dev, "Input is not ready %s\n", fw_sts_str);
728 		return -EAGAIN;
729 	}
730 
731 	reg_buf = hdr;
732 	for (i = 0; i < hdr_len / MEI_SLOT_SIZE; i++)
733 		mei_txe_input_payload_write(dev, i, reg_buf[i]);
734 
735 	reg_buf = data;
736 	for (j = 0; j < data_len / MEI_SLOT_SIZE; j++)
737 		mei_txe_input_payload_write(dev, i + j, reg_buf[j]);
738 
739 	rem = data_len & 0x3;
740 	if (rem > 0) {
741 		u32 reg = 0;
742 
743 		memcpy(&reg, (const u8 *)data + data_len - rem, rem);
744 		mei_txe_input_payload_write(dev, i + j, reg);
745 	}
746 
747 	/* after each write the whole buffer is consumed */
748 	hw->slots = 0;
749 
750 	/* Set Input-Doorbell */
751 	mei_txe_input_doorbell_set(hw);
752 
753 	return 0;
754 }
755 
756 /**
757  * mei_txe_hbuf_depth - mimics the me hbuf circular buffer
758  *
759  * @dev: the device structure
760  *
761  * Return: the TXE_HBUF_DEPTH
762  */
763 static u32 mei_txe_hbuf_depth(const struct mei_device *dev)
764 {
765 	return TXE_HBUF_DEPTH;
766 }
767 
768 /**
769  * mei_txe_hbuf_empty_slots - mimics the me hbuf circular buffer
770  *
771  * @dev: the device structure
772  *
773  * Return: always TXE_HBUF_DEPTH
774  */
775 static int mei_txe_hbuf_empty_slots(struct mei_device *dev)
776 {
777 	struct mei_txe_hw *hw = to_txe_hw(dev);
778 
779 	return hw->slots;
780 }
781 
782 /**
783  * mei_txe_count_full_read_slots - mimics the me device circular buffer
784  *
785  * @dev: the device structure
786  *
787  * Return: always buffer size in dwords count
788  */
789 static int mei_txe_count_full_read_slots(struct mei_device *dev)
790 {
791 	/* read buffers has static size */
792 	return TXE_HBUF_DEPTH;
793 }
794 
795 /**
796  * mei_txe_read_hdr - read message header which is always in 4 first bytes
797  *
798  * @dev: the device structure
799  *
800  * Return: mei message header
801  */
802 
803 static u32 mei_txe_read_hdr(const struct mei_device *dev)
804 {
805 	return mei_txe_out_data_read(dev, 0);
806 }
807 /**
808  * mei_txe_read - reads a message from the txe device.
809  *
810  * @dev: the device structure
811  * @buf: message buffer will be written
812  * @len: message size will be read
813  *
814  * Return: -EINVAL on error wrong argument and 0 on success
815  */
816 static int mei_txe_read(struct mei_device *dev,
817 		unsigned char *buf, unsigned long len)
818 {
819 
820 	struct mei_txe_hw *hw = to_txe_hw(dev);
821 	u32 *reg_buf, reg;
822 	u32 rem;
823 	u32 i;
824 
825 	if (WARN_ON(!buf || !len))
826 		return -EINVAL;
827 
828 	reg_buf = (u32 *)buf;
829 	rem = len & 0x3;
830 
831 	dev_dbg(dev->dev, "buffer-length = %lu buf[0]0x%08X\n",
832 		len, mei_txe_out_data_read(dev, 0));
833 
834 	for (i = 0; i < len / MEI_SLOT_SIZE; i++) {
835 		/* skip header: index starts from 1 */
836 		reg = mei_txe_out_data_read(dev, i + 1);
837 		dev_dbg(dev->dev, "buf[%d] = 0x%08X\n", i, reg);
838 		*reg_buf++ = reg;
839 	}
840 
841 	if (rem) {
842 		reg = mei_txe_out_data_read(dev, i + 1);
843 		memcpy(reg_buf, &reg, rem);
844 	}
845 
846 	mei_txe_output_ready_set(hw);
847 	return 0;
848 }
849 
850 /**
851  * mei_txe_hw_reset - resets host and fw.
852  *
853  * @dev: the device structure
854  * @intr_enable: if interrupt should be enabled after reset.
855  *
856  * Return: 0 on success and < 0 in case of error
857  */
858 static int mei_txe_hw_reset(struct mei_device *dev, bool intr_enable)
859 {
860 	struct mei_txe_hw *hw = to_txe_hw(dev);
861 
862 	u32 aliveness_req;
863 	/*
864 	 * read input doorbell to ensure consistency between  Bridge and SeC
865 	 * return value might be garbage return
866 	 */
867 	(void)mei_txe_sec_reg_read_silent(hw, SEC_IPC_INPUT_DOORBELL_REG);
868 
869 	aliveness_req = mei_txe_aliveness_req_get(dev);
870 	hw->aliveness = mei_txe_aliveness_get(dev);
871 
872 	/* Disable interrupts in this stage we will poll */
873 	mei_txe_intr_disable(dev);
874 
875 	/*
876 	 * If Aliveness Request and Aliveness Response are not equal then
877 	 * wait for them to be equal
878 	 * Since we might have interrupts disabled - poll for it
879 	 */
880 	if (aliveness_req != hw->aliveness)
881 		if (mei_txe_aliveness_poll(dev, aliveness_req) < 0) {
882 			dev_err(dev->dev, "wait for aliveness settle failed ... bailing out\n");
883 			return -EIO;
884 		}
885 
886 	/*
887 	 * If Aliveness Request and Aliveness Response are set then clear them
888 	 */
889 	if (aliveness_req) {
890 		mei_txe_aliveness_set(dev, 0);
891 		if (mei_txe_aliveness_poll(dev, 0) < 0) {
892 			dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
893 			return -EIO;
894 		}
895 	}
896 
897 	/*
898 	 * Set readiness RDY_CLR bit
899 	 */
900 	mei_txe_readiness_clear(dev);
901 
902 	return 0;
903 }
904 
905 /**
906  * mei_txe_hw_start - start the hardware after reset
907  *
908  * @dev: the device structure
909  *
910  * Return: 0 on success an error code otherwise
911  */
912 static int mei_txe_hw_start(struct mei_device *dev)
913 {
914 	struct mei_txe_hw *hw = to_txe_hw(dev);
915 	int ret;
916 
917 	u32 hisr;
918 
919 	/* bring back interrupts */
920 	mei_txe_intr_enable(dev);
921 
922 	ret = mei_txe_readiness_wait(dev);
923 	if (ret < 0) {
924 		dev_err(dev->dev, "waiting for readiness failed\n");
925 		return ret;
926 	}
927 
928 	/*
929 	 * If HISR.INT2_STS interrupt status bit is set then clear it.
930 	 */
931 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
932 	if (hisr & HISR_INT_2_STS)
933 		mei_txe_br_reg_write(hw, HISR_REG, HISR_INT_2_STS);
934 
935 	/* Clear the interrupt cause of OutputDoorbell */
936 	clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause);
937 
938 	ret = mei_txe_aliveness_set_sync(dev, 1);
939 	if (ret < 0) {
940 		dev_err(dev->dev, "wait for aliveness failed ... bailing out\n");
941 		return ret;
942 	}
943 
944 	pm_runtime_set_active(dev->dev);
945 
946 	/* enable input ready interrupts:
947 	 * SEC_IPC_HOST_INT_MASK.IPC_INPUT_READY_INT_MASK
948 	 */
949 	mei_txe_input_ready_interrupt_enable(dev);
950 
951 
952 	/*  Set the SICR_SEC_IPC_OUTPUT_STATUS.IPC_OUTPUT_READY bit */
953 	mei_txe_output_ready_set(hw);
954 
955 	/* Set bit SICR_HOST_IPC_READINESS.HOST_RDY
956 	 */
957 	mei_txe_readiness_set_host_rdy(dev);
958 
959 	return 0;
960 }
961 
962 /**
963  * mei_txe_check_and_ack_intrs - translate multi BAR interrupt into
964  *  single bit mask and acknowledge the interrupts
965  *
966  * @dev: the device structure
967  * @do_ack: acknowledge interrupts
968  *
969  * Return: true if found interrupts to process.
970  */
971 static bool mei_txe_check_and_ack_intrs(struct mei_device *dev, bool do_ack)
972 {
973 	struct mei_txe_hw *hw = to_txe_hw(dev);
974 	u32 hisr;
975 	u32 hhisr;
976 	u32 ipc_isr;
977 	u32 aliveness;
978 	bool generated;
979 
980 	/* read interrupt registers */
981 	hhisr = mei_txe_br_reg_read(hw, HHISR_REG);
982 	generated = (hhisr & IPC_HHIER_MSK);
983 	if (!generated)
984 		goto out;
985 
986 	hisr = mei_txe_br_reg_read(hw, HISR_REG);
987 
988 	aliveness = mei_txe_aliveness_get(dev);
989 	if (hhisr & IPC_HHIER_SEC && aliveness) {
990 		ipc_isr = mei_txe_sec_reg_read_silent(hw,
991 				SEC_IPC_HOST_INT_STATUS_REG);
992 	} else {
993 		ipc_isr = 0;
994 		hhisr &= ~IPC_HHIER_SEC;
995 	}
996 
997 	generated = generated ||
998 		(hisr & HISR_INT_STS_MSK) ||
999 		(ipc_isr & SEC_IPC_HOST_INT_STATUS_PENDING);
1000 
1001 	if (generated && do_ack) {
1002 		/* Save the interrupt causes */
1003 		hw->intr_cause |= hisr & HISR_INT_STS_MSK;
1004 		if (ipc_isr & SEC_IPC_HOST_INT_STATUS_IN_RDY)
1005 			hw->intr_cause |= TXE_INTR_IN_READY;
1006 
1007 
1008 		mei_txe_intr_disable(dev);
1009 		/* Clear the interrupts in hierarchy:
1010 		 * IPC and Bridge, than the High Level */
1011 		mei_txe_sec_reg_write_silent(hw,
1012 			SEC_IPC_HOST_INT_STATUS_REG, ipc_isr);
1013 		mei_txe_br_reg_write(hw, HISR_REG, hisr);
1014 		mei_txe_br_reg_write(hw, HHISR_REG, hhisr);
1015 	}
1016 
1017 out:
1018 	return generated;
1019 }
1020 
1021 /**
1022  * mei_txe_irq_quick_handler - The ISR of the MEI device
1023  *
1024  * @irq: The irq number
1025  * @dev_id: pointer to the device structure
1026  *
1027  * Return: IRQ_WAKE_THREAD if interrupt is designed for the device
1028  *         IRQ_NONE otherwise
1029  */
1030 irqreturn_t mei_txe_irq_quick_handler(int irq, void *dev_id)
1031 {
1032 	struct mei_device *dev = dev_id;
1033 
1034 	if (mei_txe_check_and_ack_intrs(dev, true))
1035 		return IRQ_WAKE_THREAD;
1036 	return IRQ_NONE;
1037 }
1038 
1039 
1040 /**
1041  * mei_txe_irq_thread_handler - txe interrupt thread
1042  *
1043  * @irq: The irq number
1044  * @dev_id: pointer to the device structure
1045  *
1046  * Return: IRQ_HANDLED
1047  */
1048 irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
1049 {
1050 	struct mei_device *dev = (struct mei_device *) dev_id;
1051 	struct mei_txe_hw *hw = to_txe_hw(dev);
1052 	struct list_head cmpl_list;
1053 	s32 slots;
1054 	int rets = 0;
1055 
1056 	dev_dbg(dev->dev, "irq thread: Interrupt Registers HHISR|HISR|SEC=%02X|%04X|%02X\n",
1057 		mei_txe_br_reg_read(hw, HHISR_REG),
1058 		mei_txe_br_reg_read(hw, HISR_REG),
1059 		mei_txe_sec_reg_read_silent(hw, SEC_IPC_HOST_INT_STATUS_REG));
1060 
1061 
1062 	/* initialize our complete list */
1063 	mutex_lock(&dev->device_lock);
1064 	INIT_LIST_HEAD(&cmpl_list);
1065 
1066 	if (pci_dev_msi_enabled(to_pci_dev(dev->dev)))
1067 		mei_txe_check_and_ack_intrs(dev, true);
1068 
1069 	/* show irq events */
1070 	mei_txe_pending_interrupts(dev);
1071 
1072 	hw->aliveness = mei_txe_aliveness_get(dev);
1073 	hw->readiness = mei_txe_readiness_get(dev);
1074 
1075 	/* Readiness:
1076 	 * Detection of TXE driver going through reset
1077 	 * or TXE driver resetting the HECI interface.
1078 	 */
1079 	if (test_and_clear_bit(TXE_INTR_READINESS_BIT, &hw->intr_cause)) {
1080 		dev_dbg(dev->dev, "Readiness Interrupt was received...\n");
1081 
1082 		/* Check if SeC is going through reset */
1083 		if (mei_txe_readiness_is_sec_rdy(hw->readiness)) {
1084 			dev_dbg(dev->dev, "we need to start the dev.\n");
1085 			dev->recvd_hw_ready = true;
1086 		} else {
1087 			dev->recvd_hw_ready = false;
1088 			if (dev->dev_state != MEI_DEV_RESETTING) {
1089 
1090 				dev_warn(dev->dev, "FW not ready: resetting.\n");
1091 				schedule_work(&dev->reset_work);
1092 				goto end;
1093 
1094 			}
1095 		}
1096 		wake_up(&dev->wait_hw_ready);
1097 	}
1098 
1099 	/************************************************************/
1100 	/* Check interrupt cause:
1101 	 * Aliveness: Detection of SeC acknowledge of host request that
1102 	 * it remain alive or host cancellation of that request.
1103 	 */
1104 
1105 	if (test_and_clear_bit(TXE_INTR_ALIVENESS_BIT, &hw->intr_cause)) {
1106 		/* Clear the interrupt cause */
1107 		dev_dbg(dev->dev,
1108 			"Aliveness Interrupt: Status: %d\n", hw->aliveness);
1109 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
1110 		if (waitqueue_active(&hw->wait_aliveness_resp))
1111 			wake_up(&hw->wait_aliveness_resp);
1112 	}
1113 
1114 
1115 	/* Output Doorbell:
1116 	 * Detection of SeC having sent output to host
1117 	 */
1118 	slots = mei_count_full_read_slots(dev);
1119 	if (test_and_clear_bit(TXE_INTR_OUT_DB_BIT, &hw->intr_cause)) {
1120 		/* Read from TXE */
1121 		rets = mei_irq_read_handler(dev, &cmpl_list, &slots);
1122 		if (rets &&
1123 		    (dev->dev_state != MEI_DEV_RESETTING &&
1124 		     dev->dev_state != MEI_DEV_POWER_DOWN)) {
1125 			dev_err(dev->dev,
1126 				"mei_irq_read_handler ret = %d.\n", rets);
1127 
1128 			schedule_work(&dev->reset_work);
1129 			goto end;
1130 		}
1131 	}
1132 	/* Input Ready: Detection if host can write to SeC */
1133 	if (test_and_clear_bit(TXE_INTR_IN_READY_BIT, &hw->intr_cause)) {
1134 		dev->hbuf_is_ready = true;
1135 		hw->slots = TXE_HBUF_DEPTH;
1136 	}
1137 
1138 	if (hw->aliveness && dev->hbuf_is_ready) {
1139 		/* get the real register value */
1140 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1141 		rets = mei_irq_write_handler(dev, &cmpl_list);
1142 		if (rets && rets != -EMSGSIZE)
1143 			dev_err(dev->dev, "mei_irq_write_handler ret = %d.\n",
1144 				rets);
1145 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1146 	}
1147 
1148 	mei_irq_compl_handler(dev, &cmpl_list);
1149 
1150 end:
1151 	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
1152 
1153 	mutex_unlock(&dev->device_lock);
1154 
1155 	mei_enable_interrupts(dev);
1156 	return IRQ_HANDLED;
1157 }
1158 
1159 static const struct mei_hw_ops mei_txe_hw_ops = {
1160 
1161 	.host_is_ready = mei_txe_host_is_ready,
1162 
1163 	.fw_status = mei_txe_fw_status,
1164 	.pg_state = mei_txe_pg_state,
1165 
1166 	.hw_is_ready = mei_txe_hw_is_ready,
1167 	.hw_reset = mei_txe_hw_reset,
1168 	.hw_config = mei_txe_hw_config,
1169 	.hw_start = mei_txe_hw_start,
1170 
1171 	.pg_in_transition = mei_txe_pg_in_transition,
1172 	.pg_is_enabled = mei_txe_pg_is_enabled,
1173 
1174 	.intr_clear = mei_txe_intr_clear,
1175 	.intr_enable = mei_txe_intr_enable,
1176 	.intr_disable = mei_txe_intr_disable,
1177 	.synchronize_irq = mei_txe_synchronize_irq,
1178 
1179 	.hbuf_free_slots = mei_txe_hbuf_empty_slots,
1180 	.hbuf_is_ready = mei_txe_is_input_ready,
1181 	.hbuf_depth = mei_txe_hbuf_depth,
1182 
1183 	.write = mei_txe_write,
1184 
1185 	.rdbuf_full_slots = mei_txe_count_full_read_slots,
1186 	.read_hdr = mei_txe_read_hdr,
1187 
1188 	.read = mei_txe_read,
1189 
1190 };
1191 
1192 /**
1193  * mei_txe_dev_init - allocates and initializes txe hardware specific structure
1194  *
1195  * @pdev: pci device
1196  *
1197  * Return: struct mei_device * on success or NULL
1198  */
1199 struct mei_device *mei_txe_dev_init(struct pci_dev *pdev)
1200 {
1201 	struct mei_device *dev;
1202 	struct mei_txe_hw *hw;
1203 
1204 	dev = devm_kzalloc(&pdev->dev, sizeof(*dev) + sizeof(*hw), GFP_KERNEL);
1205 	if (!dev)
1206 		return NULL;
1207 
1208 	mei_device_init(dev, &pdev->dev, &mei_txe_hw_ops);
1209 
1210 	hw = to_txe_hw(dev);
1211 
1212 	init_waitqueue_head(&hw->wait_aliveness_resp);
1213 
1214 	return dev;
1215 }
1216 
1217 /**
1218  * mei_txe_setup_satt2 - SATT2 configuration for DMA support.
1219  *
1220  * @dev:   the device structure
1221  * @addr:  physical address start of the range
1222  * @range: physical range size
1223  *
1224  * Return: 0 on success an error code otherwise
1225  */
1226 int mei_txe_setup_satt2(struct mei_device *dev, phys_addr_t addr, u32 range)
1227 {
1228 	struct mei_txe_hw *hw = to_txe_hw(dev);
1229 
1230 	u32 lo32 = lower_32_bits(addr);
1231 	u32 hi32 = upper_32_bits(addr);
1232 	u32 ctrl;
1233 
1234 	/* SATT is limited to 36 Bits */
1235 	if (hi32 & ~0xF)
1236 		return -EINVAL;
1237 
1238 	/* SATT has to be 16Byte aligned */
1239 	if (lo32 & 0xF)
1240 		return -EINVAL;
1241 
1242 	/* SATT range has to be 4Bytes aligned */
1243 	if (range & 0x4)
1244 		return -EINVAL;
1245 
1246 	/* SATT is limited to 32 MB range*/
1247 	if (range > SATT_RANGE_MAX)
1248 		return -EINVAL;
1249 
1250 	ctrl = SATT2_CTRL_VALID_MSK;
1251 	ctrl |= hi32  << SATT2_CTRL_BR_BASE_ADDR_REG_SHIFT;
1252 
1253 	mei_txe_br_reg_write(hw, SATT2_SAP_SIZE_REG, range);
1254 	mei_txe_br_reg_write(hw, SATT2_BRG_BA_LSB_REG, lo32);
1255 	mei_txe_br_reg_write(hw, SATT2_CTRL_REG, ctrl);
1256 	dev_dbg(dev->dev, "SATT2: SAP_SIZE_OFFSET=0x%08X, BRG_BA_LSB_OFFSET=0x%08X, CTRL_OFFSET=0x%08X\n",
1257 		range, lo32, ctrl);
1258 
1259 	return 0;
1260 }
1261