xref: /openbmc/linux/drivers/misc/mei/hw-me.c (revision e983940270f10fe8551baf0098be76ea478294a3)
1 /*
2  *
3  * Intel Management Engine Interface (Intel MEI) Linux driver
4  * Copyright (c) 2003-2012, 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 
19 #include <linux/kthread.h>
20 #include <linux/interrupt.h>
21 #include <linux/pm_runtime.h>
22 
23 #include "mei_dev.h"
24 #include "hbm.h"
25 
26 #include "hw-me.h"
27 #include "hw-me-regs.h"
28 
29 #include "mei-trace.h"
30 
31 /**
32  * mei_me_reg_read - Reads 32bit data from the mei device
33  *
34  * @hw: the me hardware structure
35  * @offset: offset from which to read the data
36  *
37  * Return: register value (u32)
38  */
39 static inline u32 mei_me_reg_read(const struct mei_me_hw *hw,
40 			       unsigned long offset)
41 {
42 	return ioread32(hw->mem_addr + offset);
43 }
44 
45 
46 /**
47  * mei_me_reg_write - Writes 32bit data to the mei device
48  *
49  * @hw: the me hardware structure
50  * @offset: offset from which to write the data
51  * @value: register value to write (u32)
52  */
53 static inline void mei_me_reg_write(const struct mei_me_hw *hw,
54 				 unsigned long offset, u32 value)
55 {
56 	iowrite32(value, hw->mem_addr + offset);
57 }
58 
59 /**
60  * mei_me_mecbrw_read - Reads 32bit data from ME circular buffer
61  *  read window register
62  *
63  * @dev: the device structure
64  *
65  * Return: ME_CB_RW register value (u32)
66  */
67 static inline u32 mei_me_mecbrw_read(const struct mei_device *dev)
68 {
69 	return mei_me_reg_read(to_me_hw(dev), ME_CB_RW);
70 }
71 
72 /**
73  * mei_me_hcbww_write - write 32bit data to the host circular buffer
74  *
75  * @dev: the device structure
76  * @data: 32bit data to be written to the host circular buffer
77  */
78 static inline void mei_me_hcbww_write(struct mei_device *dev, u32 data)
79 {
80 	mei_me_reg_write(to_me_hw(dev), H_CB_WW, data);
81 }
82 
83 /**
84  * mei_me_mecsr_read - Reads 32bit data from the ME CSR
85  *
86  * @dev: the device structure
87  *
88  * Return: ME_CSR_HA register value (u32)
89  */
90 static inline u32 mei_me_mecsr_read(const struct mei_device *dev)
91 {
92 	u32 reg;
93 
94 	reg = mei_me_reg_read(to_me_hw(dev), ME_CSR_HA);
95 	trace_mei_reg_read(dev->dev, "ME_CSR_HA", ME_CSR_HA, reg);
96 
97 	return reg;
98 }
99 
100 /**
101  * mei_hcsr_read - Reads 32bit data from the host CSR
102  *
103  * @dev: the device structure
104  *
105  * Return: H_CSR register value (u32)
106  */
107 static inline u32 mei_hcsr_read(const struct mei_device *dev)
108 {
109 	u32 reg;
110 
111 	reg = mei_me_reg_read(to_me_hw(dev), H_CSR);
112 	trace_mei_reg_read(dev->dev, "H_CSR", H_CSR, reg);
113 
114 	return reg;
115 }
116 
117 /**
118  * mei_hcsr_write - writes H_CSR register to the mei device
119  *
120  * @dev: the device structure
121  * @reg: new register value
122  */
123 static inline void mei_hcsr_write(struct mei_device *dev, u32 reg)
124 {
125 	trace_mei_reg_write(dev->dev, "H_CSR", H_CSR, reg);
126 	mei_me_reg_write(to_me_hw(dev), H_CSR, reg);
127 }
128 
129 /**
130  * mei_hcsr_set - writes H_CSR register to the mei device,
131  * and ignores the H_IS bit for it is write-one-to-zero.
132  *
133  * @dev: the device structure
134  * @reg: new register value
135  */
136 static inline void mei_hcsr_set(struct mei_device *dev, u32 reg)
137 {
138 	reg &= ~H_CSR_IS_MASK;
139 	mei_hcsr_write(dev, reg);
140 }
141 
142 /**
143  * mei_me_d0i3c_read - Reads 32bit data from the D0I3C register
144  *
145  * @dev: the device structure
146  *
147  * Return: H_D0I3C register value (u32)
148  */
149 static inline u32 mei_me_d0i3c_read(const struct mei_device *dev)
150 {
151 	u32 reg;
152 
153 	reg = mei_me_reg_read(to_me_hw(dev), H_D0I3C);
154 	trace_mei_reg_read(dev->dev, "H_D0I3C", H_D0I3C, reg);
155 
156 	return reg;
157 }
158 
159 /**
160  * mei_me_d0i3c_write - writes H_D0I3C register to device
161  *
162  * @dev: the device structure
163  * @reg: new register value
164  */
165 static inline void mei_me_d0i3c_write(struct mei_device *dev, u32 reg)
166 {
167 	trace_mei_reg_write(dev->dev, "H_D0I3C", H_D0I3C, reg);
168 	mei_me_reg_write(to_me_hw(dev), H_D0I3C, reg);
169 }
170 
171 /**
172  * mei_me_fw_status - read fw status register from pci config space
173  *
174  * @dev: mei device
175  * @fw_status: fw status register values
176  *
177  * Return: 0 on success, error otherwise
178  */
179 static int mei_me_fw_status(struct mei_device *dev,
180 			    struct mei_fw_status *fw_status)
181 {
182 	struct pci_dev *pdev = to_pci_dev(dev->dev);
183 	struct mei_me_hw *hw = to_me_hw(dev);
184 	const struct mei_fw_status *fw_src = &hw->cfg->fw_status;
185 	int ret;
186 	int i;
187 
188 	if (!fw_status)
189 		return -EINVAL;
190 
191 	fw_status->count = fw_src->count;
192 	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
193 		ret = pci_read_config_dword(pdev, fw_src->status[i],
194 					    &fw_status->status[i]);
195 		trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HSF_X",
196 				       fw_src->status[i],
197 				       fw_status->status[i]);
198 		if (ret)
199 			return ret;
200 	}
201 
202 	return 0;
203 }
204 
205 /**
206  * mei_me_hw_config - configure hw dependent settings
207  *
208  * @dev: mei device
209  */
210 static void mei_me_hw_config(struct mei_device *dev)
211 {
212 	struct pci_dev *pdev = to_pci_dev(dev->dev);
213 	struct mei_me_hw *hw = to_me_hw(dev);
214 	u32 hcsr, reg;
215 
216 	/* Doesn't change in runtime */
217 	hcsr = mei_hcsr_read(dev);
218 	dev->hbuf_depth = (hcsr & H_CBD) >> 24;
219 
220 	reg = 0;
221 	pci_read_config_dword(pdev, PCI_CFG_HFS_1, &reg);
222 	trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
223 	hw->d0i3_supported =
224 		((reg & PCI_CFG_HFS_1_D0I3_MSK) == PCI_CFG_HFS_1_D0I3_MSK);
225 
226 	hw->pg_state = MEI_PG_OFF;
227 	if (hw->d0i3_supported) {
228 		reg = mei_me_d0i3c_read(dev);
229 		if (reg & H_D0I3C_I3)
230 			hw->pg_state = MEI_PG_ON;
231 	}
232 }
233 
234 /**
235  * mei_me_pg_state  - translate internal pg state
236  *   to the mei power gating state
237  *
238  * @dev:  mei device
239  *
240  * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
241  */
242 static inline enum mei_pg_state mei_me_pg_state(struct mei_device *dev)
243 {
244 	struct mei_me_hw *hw = to_me_hw(dev);
245 
246 	return hw->pg_state;
247 }
248 
249 /**
250  * mei_me_intr_clear - clear and stop interrupts
251  *
252  * @dev: the device structure
253  */
254 static void mei_me_intr_clear(struct mei_device *dev)
255 {
256 	u32 hcsr = mei_hcsr_read(dev);
257 
258 	if (hcsr & H_CSR_IS_MASK)
259 		mei_hcsr_write(dev, hcsr);
260 }
261 /**
262  * mei_me_intr_enable - enables mei device interrupts
263  *
264  * @dev: the device structure
265  */
266 static void mei_me_intr_enable(struct mei_device *dev)
267 {
268 	u32 hcsr = mei_hcsr_read(dev);
269 
270 	hcsr |= H_CSR_IE_MASK;
271 	mei_hcsr_set(dev, hcsr);
272 }
273 
274 /**
275  * mei_me_intr_disable - disables mei device interrupts
276  *
277  * @dev: the device structure
278  */
279 static void mei_me_intr_disable(struct mei_device *dev)
280 {
281 	u32 hcsr = mei_hcsr_read(dev);
282 
283 	hcsr  &= ~H_CSR_IE_MASK;
284 	mei_hcsr_set(dev, hcsr);
285 }
286 
287 /**
288  * mei_me_hw_reset_release - release device from the reset
289  *
290  * @dev: the device structure
291  */
292 static void mei_me_hw_reset_release(struct mei_device *dev)
293 {
294 	u32 hcsr = mei_hcsr_read(dev);
295 
296 	hcsr |= H_IG;
297 	hcsr &= ~H_RST;
298 	mei_hcsr_set(dev, hcsr);
299 
300 	/* complete this write before we set host ready on another CPU */
301 	mmiowb();
302 }
303 
304 /**
305  * mei_me_host_set_ready - enable device
306  *
307  * @dev: mei device
308  */
309 static void mei_me_host_set_ready(struct mei_device *dev)
310 {
311 	u32 hcsr = mei_hcsr_read(dev);
312 
313 	hcsr |= H_CSR_IE_MASK | H_IG | H_RDY;
314 	mei_hcsr_set(dev, hcsr);
315 }
316 
317 /**
318  * mei_me_host_is_ready - check whether the host has turned ready
319  *
320  * @dev: mei device
321  * Return: bool
322  */
323 static bool mei_me_host_is_ready(struct mei_device *dev)
324 {
325 	u32 hcsr = mei_hcsr_read(dev);
326 
327 	return (hcsr & H_RDY) == H_RDY;
328 }
329 
330 /**
331  * mei_me_hw_is_ready - check whether the me(hw) has turned ready
332  *
333  * @dev: mei device
334  * Return: bool
335  */
336 static bool mei_me_hw_is_ready(struct mei_device *dev)
337 {
338 	u32 mecsr = mei_me_mecsr_read(dev);
339 
340 	return (mecsr & ME_RDY_HRA) == ME_RDY_HRA;
341 }
342 
343 /**
344  * mei_me_hw_ready_wait - wait until the me(hw) has turned ready
345  *  or timeout is reached
346  *
347  * @dev: mei device
348  * Return: 0 on success, error otherwise
349  */
350 static int mei_me_hw_ready_wait(struct mei_device *dev)
351 {
352 	mutex_unlock(&dev->device_lock);
353 	wait_event_timeout(dev->wait_hw_ready,
354 			dev->recvd_hw_ready,
355 			mei_secs_to_jiffies(MEI_HW_READY_TIMEOUT));
356 	mutex_lock(&dev->device_lock);
357 	if (!dev->recvd_hw_ready) {
358 		dev_err(dev->dev, "wait hw ready failed\n");
359 		return -ETIME;
360 	}
361 
362 	mei_me_hw_reset_release(dev);
363 	dev->recvd_hw_ready = false;
364 	return 0;
365 }
366 
367 /**
368  * mei_me_hw_start - hw start routine
369  *
370  * @dev: mei device
371  * Return: 0 on success, error otherwise
372  */
373 static int mei_me_hw_start(struct mei_device *dev)
374 {
375 	int ret = mei_me_hw_ready_wait(dev);
376 
377 	if (ret)
378 		return ret;
379 	dev_dbg(dev->dev, "hw is ready\n");
380 
381 	mei_me_host_set_ready(dev);
382 	return ret;
383 }
384 
385 
386 /**
387  * mei_hbuf_filled_slots - gets number of device filled buffer slots
388  *
389  * @dev: the device structure
390  *
391  * Return: number of filled slots
392  */
393 static unsigned char mei_hbuf_filled_slots(struct mei_device *dev)
394 {
395 	u32 hcsr;
396 	char read_ptr, write_ptr;
397 
398 	hcsr = mei_hcsr_read(dev);
399 
400 	read_ptr = (char) ((hcsr & H_CBRP) >> 8);
401 	write_ptr = (char) ((hcsr & H_CBWP) >> 16);
402 
403 	return (unsigned char) (write_ptr - read_ptr);
404 }
405 
406 /**
407  * mei_me_hbuf_is_empty - checks if host buffer is empty.
408  *
409  * @dev: the device structure
410  *
411  * Return: true if empty, false - otherwise.
412  */
413 static bool mei_me_hbuf_is_empty(struct mei_device *dev)
414 {
415 	return mei_hbuf_filled_slots(dev) == 0;
416 }
417 
418 /**
419  * mei_me_hbuf_empty_slots - counts write empty slots.
420  *
421  * @dev: the device structure
422  *
423  * Return: -EOVERFLOW if overflow, otherwise empty slots count
424  */
425 static int mei_me_hbuf_empty_slots(struct mei_device *dev)
426 {
427 	unsigned char filled_slots, empty_slots;
428 
429 	filled_slots = mei_hbuf_filled_slots(dev);
430 	empty_slots = dev->hbuf_depth - filled_slots;
431 
432 	/* check for overflow */
433 	if (filled_slots > dev->hbuf_depth)
434 		return -EOVERFLOW;
435 
436 	return empty_slots;
437 }
438 
439 /**
440  * mei_me_hbuf_max_len - returns size of hw buffer.
441  *
442  * @dev: the device structure
443  *
444  * Return: size of hw buffer in bytes
445  */
446 static size_t mei_me_hbuf_max_len(const struct mei_device *dev)
447 {
448 	return dev->hbuf_depth * sizeof(u32) - sizeof(struct mei_msg_hdr);
449 }
450 
451 
452 /**
453  * mei_me_write_message - writes a message to mei device.
454  *
455  * @dev: the device structure
456  * @header: mei HECI header of message
457  * @buf: message payload will be written
458  *
459  * Return: -EIO if write has failed
460  */
461 static int mei_me_write_message(struct mei_device *dev,
462 			struct mei_msg_hdr *header,
463 			unsigned char *buf)
464 {
465 	unsigned long rem;
466 	unsigned long length = header->length;
467 	u32 *reg_buf = (u32 *)buf;
468 	u32 hcsr;
469 	u32 dw_cnt;
470 	int i;
471 	int empty_slots;
472 
473 	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(header));
474 
475 	empty_slots = mei_hbuf_empty_slots(dev);
476 	dev_dbg(dev->dev, "empty slots = %hu.\n", empty_slots);
477 
478 	dw_cnt = mei_data2slots(length);
479 	if (empty_slots < 0 || dw_cnt > empty_slots)
480 		return -EMSGSIZE;
481 
482 	mei_me_hcbww_write(dev, *((u32 *) header));
483 
484 	for (i = 0; i < length / 4; i++)
485 		mei_me_hcbww_write(dev, reg_buf[i]);
486 
487 	rem = length & 0x3;
488 	if (rem > 0) {
489 		u32 reg = 0;
490 
491 		memcpy(&reg, &buf[length - rem], rem);
492 		mei_me_hcbww_write(dev, reg);
493 	}
494 
495 	hcsr = mei_hcsr_read(dev) | H_IG;
496 	mei_hcsr_set(dev, hcsr);
497 	if (!mei_me_hw_is_ready(dev))
498 		return -EIO;
499 
500 	return 0;
501 }
502 
503 /**
504  * mei_me_count_full_read_slots - counts read full slots.
505  *
506  * @dev: the device structure
507  *
508  * Return: -EOVERFLOW if overflow, otherwise filled slots count
509  */
510 static int mei_me_count_full_read_slots(struct mei_device *dev)
511 {
512 	u32 me_csr;
513 	char read_ptr, write_ptr;
514 	unsigned char buffer_depth, filled_slots;
515 
516 	me_csr = mei_me_mecsr_read(dev);
517 	buffer_depth = (unsigned char)((me_csr & ME_CBD_HRA) >> 24);
518 	read_ptr = (char) ((me_csr & ME_CBRP_HRA) >> 8);
519 	write_ptr = (char) ((me_csr & ME_CBWP_HRA) >> 16);
520 	filled_slots = (unsigned char) (write_ptr - read_ptr);
521 
522 	/* check for overflow */
523 	if (filled_slots > buffer_depth)
524 		return -EOVERFLOW;
525 
526 	dev_dbg(dev->dev, "filled_slots =%08x\n", filled_slots);
527 	return (int)filled_slots;
528 }
529 
530 /**
531  * mei_me_read_slots - reads a message from mei device.
532  *
533  * @dev: the device structure
534  * @buffer: message buffer will be written
535  * @buffer_length: message size will be read
536  *
537  * Return: always 0
538  */
539 static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
540 		    unsigned long buffer_length)
541 {
542 	u32 *reg_buf = (u32 *)buffer;
543 	u32 hcsr;
544 
545 	for (; buffer_length >= sizeof(u32); buffer_length -= sizeof(u32))
546 		*reg_buf++ = mei_me_mecbrw_read(dev);
547 
548 	if (buffer_length > 0) {
549 		u32 reg = mei_me_mecbrw_read(dev);
550 
551 		memcpy(reg_buf, &reg, buffer_length);
552 	}
553 
554 	hcsr = mei_hcsr_read(dev) | H_IG;
555 	mei_hcsr_set(dev, hcsr);
556 	return 0;
557 }
558 
559 /**
560  * mei_me_pg_set - write pg enter register
561  *
562  * @dev: the device structure
563  */
564 static void mei_me_pg_set(struct mei_device *dev)
565 {
566 	struct mei_me_hw *hw = to_me_hw(dev);
567 	u32 reg;
568 
569 	reg = mei_me_reg_read(hw, H_HPG_CSR);
570 	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
571 
572 	reg |= H_HPG_CSR_PGI;
573 
574 	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
575 	mei_me_reg_write(hw, H_HPG_CSR, reg);
576 }
577 
578 /**
579  * mei_me_pg_unset - write pg exit register
580  *
581  * @dev: the device structure
582  */
583 static void mei_me_pg_unset(struct mei_device *dev)
584 {
585 	struct mei_me_hw *hw = to_me_hw(dev);
586 	u32 reg;
587 
588 	reg = mei_me_reg_read(hw, H_HPG_CSR);
589 	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
590 
591 	WARN(!(reg & H_HPG_CSR_PGI), "PGI is not set\n");
592 
593 	reg |= H_HPG_CSR_PGIHEXR;
594 
595 	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
596 	mei_me_reg_write(hw, H_HPG_CSR, reg);
597 }
598 
599 /**
600  * mei_me_pg_legacy_enter_sync - perform legacy pg entry procedure
601  *
602  * @dev: the device structure
603  *
604  * Return: 0 on success an error code otherwise
605  */
606 static int mei_me_pg_legacy_enter_sync(struct mei_device *dev)
607 {
608 	struct mei_me_hw *hw = to_me_hw(dev);
609 	unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
610 	int ret;
611 
612 	dev->pg_event = MEI_PG_EVENT_WAIT;
613 
614 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
615 	if (ret)
616 		return ret;
617 
618 	mutex_unlock(&dev->device_lock);
619 	wait_event_timeout(dev->wait_pg,
620 		dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
621 	mutex_lock(&dev->device_lock);
622 
623 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED) {
624 		mei_me_pg_set(dev);
625 		ret = 0;
626 	} else {
627 		ret = -ETIME;
628 	}
629 
630 	dev->pg_event = MEI_PG_EVENT_IDLE;
631 	hw->pg_state = MEI_PG_ON;
632 
633 	return ret;
634 }
635 
636 /**
637  * mei_me_pg_legacy_exit_sync - perform legacy pg exit procedure
638  *
639  * @dev: the device structure
640  *
641  * Return: 0 on success an error code otherwise
642  */
643 static int mei_me_pg_legacy_exit_sync(struct mei_device *dev)
644 {
645 	struct mei_me_hw *hw = to_me_hw(dev);
646 	unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
647 	int ret;
648 
649 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED)
650 		goto reply;
651 
652 	dev->pg_event = MEI_PG_EVENT_WAIT;
653 
654 	mei_me_pg_unset(dev);
655 
656 	mutex_unlock(&dev->device_lock);
657 	wait_event_timeout(dev->wait_pg,
658 		dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
659 	mutex_lock(&dev->device_lock);
660 
661 reply:
662 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
663 		ret = -ETIME;
664 		goto out;
665 	}
666 
667 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
668 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD);
669 	if (ret)
670 		return ret;
671 
672 	mutex_unlock(&dev->device_lock);
673 	wait_event_timeout(dev->wait_pg,
674 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED, timeout);
675 	mutex_lock(&dev->device_lock);
676 
677 	if (dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED)
678 		ret = 0;
679 	else
680 		ret = -ETIME;
681 
682 out:
683 	dev->pg_event = MEI_PG_EVENT_IDLE;
684 	hw->pg_state = MEI_PG_OFF;
685 
686 	return ret;
687 }
688 
689 /**
690  * mei_me_pg_in_transition - is device now in pg transition
691  *
692  * @dev: the device structure
693  *
694  * Return: true if in pg transition, false otherwise
695  */
696 static bool mei_me_pg_in_transition(struct mei_device *dev)
697 {
698 	return dev->pg_event >= MEI_PG_EVENT_WAIT &&
699 	       dev->pg_event <= MEI_PG_EVENT_INTR_WAIT;
700 }
701 
702 /**
703  * mei_me_pg_is_enabled - detect if PG is supported by HW
704  *
705  * @dev: the device structure
706  *
707  * Return: true is pg supported, false otherwise
708  */
709 static bool mei_me_pg_is_enabled(struct mei_device *dev)
710 {
711 	struct mei_me_hw *hw = to_me_hw(dev);
712 	u32 reg = mei_me_mecsr_read(dev);
713 
714 	if (hw->d0i3_supported)
715 		return true;
716 
717 	if ((reg & ME_PGIC_HRA) == 0)
718 		goto notsupported;
719 
720 	if (!dev->hbm_f_pg_supported)
721 		goto notsupported;
722 
723 	return true;
724 
725 notsupported:
726 	dev_dbg(dev->dev, "pg: not supported: d0i3 = %d HGP = %d hbm version %d.%d ?= %d.%d\n",
727 		hw->d0i3_supported,
728 		!!(reg & ME_PGIC_HRA),
729 		dev->version.major_version,
730 		dev->version.minor_version,
731 		HBM_MAJOR_VERSION_PGI,
732 		HBM_MINOR_VERSION_PGI);
733 
734 	return false;
735 }
736 
737 /**
738  * mei_me_d0i3_set - write d0i3 register bit on mei device.
739  *
740  * @dev: the device structure
741  * @intr: ask for interrupt
742  *
743  * Return: D0I3C register value
744  */
745 static u32 mei_me_d0i3_set(struct mei_device *dev, bool intr)
746 {
747 	u32 reg = mei_me_d0i3c_read(dev);
748 
749 	reg |= H_D0I3C_I3;
750 	if (intr)
751 		reg |= H_D0I3C_IR;
752 	else
753 		reg &= ~H_D0I3C_IR;
754 	mei_me_d0i3c_write(dev, reg);
755 	/* read it to ensure HW consistency */
756 	reg = mei_me_d0i3c_read(dev);
757 	return reg;
758 }
759 
760 /**
761  * mei_me_d0i3_unset - clean d0i3 register bit on mei device.
762  *
763  * @dev: the device structure
764  *
765  * Return: D0I3C register value
766  */
767 static u32 mei_me_d0i3_unset(struct mei_device *dev)
768 {
769 	u32 reg = mei_me_d0i3c_read(dev);
770 
771 	reg &= ~H_D0I3C_I3;
772 	reg |= H_D0I3C_IR;
773 	mei_me_d0i3c_write(dev, reg);
774 	/* read it to ensure HW consistency */
775 	reg = mei_me_d0i3c_read(dev);
776 	return reg;
777 }
778 
779 /**
780  * mei_me_d0i3_enter_sync - perform d0i3 entry procedure
781  *
782  * @dev: the device structure
783  *
784  * Return: 0 on success an error code otherwise
785  */
786 static int mei_me_d0i3_enter_sync(struct mei_device *dev)
787 {
788 	struct mei_me_hw *hw = to_me_hw(dev);
789 	unsigned long d0i3_timeout = mei_secs_to_jiffies(MEI_D0I3_TIMEOUT);
790 	unsigned long pgi_timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT);
791 	int ret;
792 	u32 reg;
793 
794 	reg = mei_me_d0i3c_read(dev);
795 	if (reg & H_D0I3C_I3) {
796 		/* we are in d0i3, nothing to do */
797 		dev_dbg(dev->dev, "d0i3 set not needed\n");
798 		ret = 0;
799 		goto on;
800 	}
801 
802 	/* PGI entry procedure */
803 	dev->pg_event = MEI_PG_EVENT_WAIT;
804 
805 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
806 	if (ret)
807 		/* FIXME: should we reset here? */
808 		goto out;
809 
810 	mutex_unlock(&dev->device_lock);
811 	wait_event_timeout(dev->wait_pg,
812 		dev->pg_event == MEI_PG_EVENT_RECEIVED, pgi_timeout);
813 	mutex_lock(&dev->device_lock);
814 
815 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
816 		ret = -ETIME;
817 		goto out;
818 	}
819 	/* end PGI entry procedure */
820 
821 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
822 
823 	reg = mei_me_d0i3_set(dev, true);
824 	if (!(reg & H_D0I3C_CIP)) {
825 		dev_dbg(dev->dev, "d0i3 enter wait not needed\n");
826 		ret = 0;
827 		goto on;
828 	}
829 
830 	mutex_unlock(&dev->device_lock);
831 	wait_event_timeout(dev->wait_pg,
832 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED, d0i3_timeout);
833 	mutex_lock(&dev->device_lock);
834 
835 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
836 		reg = mei_me_d0i3c_read(dev);
837 		if (!(reg & H_D0I3C_I3)) {
838 			ret = -ETIME;
839 			goto out;
840 		}
841 	}
842 
843 	ret = 0;
844 on:
845 	hw->pg_state = MEI_PG_ON;
846 out:
847 	dev->pg_event = MEI_PG_EVENT_IDLE;
848 	dev_dbg(dev->dev, "d0i3 enter ret = %d\n", ret);
849 	return ret;
850 }
851 
852 /**
853  * mei_me_d0i3_enter - perform d0i3 entry procedure
854  *   no hbm PG handshake
855  *   no waiting for confirmation; runs with interrupts
856  *   disabled
857  *
858  * @dev: the device structure
859  *
860  * Return: 0 on success an error code otherwise
861  */
862 static int mei_me_d0i3_enter(struct mei_device *dev)
863 {
864 	struct mei_me_hw *hw = to_me_hw(dev);
865 	u32 reg;
866 
867 	reg = mei_me_d0i3c_read(dev);
868 	if (reg & H_D0I3C_I3) {
869 		/* we are in d0i3, nothing to do */
870 		dev_dbg(dev->dev, "already d0i3 : set not needed\n");
871 		goto on;
872 	}
873 
874 	mei_me_d0i3_set(dev, false);
875 on:
876 	hw->pg_state = MEI_PG_ON;
877 	dev->pg_event = MEI_PG_EVENT_IDLE;
878 	dev_dbg(dev->dev, "d0i3 enter\n");
879 	return 0;
880 }
881 
882 /**
883  * mei_me_d0i3_exit_sync - perform d0i3 exit procedure
884  *
885  * @dev: the device structure
886  *
887  * Return: 0 on success an error code otherwise
888  */
889 static int mei_me_d0i3_exit_sync(struct mei_device *dev)
890 {
891 	struct mei_me_hw *hw = to_me_hw(dev);
892 	unsigned long timeout = mei_secs_to_jiffies(MEI_D0I3_TIMEOUT);
893 	int ret;
894 	u32 reg;
895 
896 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
897 
898 	reg = mei_me_d0i3c_read(dev);
899 	if (!(reg & H_D0I3C_I3)) {
900 		/* we are not in d0i3, nothing to do */
901 		dev_dbg(dev->dev, "d0i3 exit not needed\n");
902 		ret = 0;
903 		goto off;
904 	}
905 
906 	reg = mei_me_d0i3_unset(dev);
907 	if (!(reg & H_D0I3C_CIP)) {
908 		dev_dbg(dev->dev, "d0i3 exit wait not needed\n");
909 		ret = 0;
910 		goto off;
911 	}
912 
913 	mutex_unlock(&dev->device_lock);
914 	wait_event_timeout(dev->wait_pg,
915 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED, timeout);
916 	mutex_lock(&dev->device_lock);
917 
918 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
919 		reg = mei_me_d0i3c_read(dev);
920 		if (reg & H_D0I3C_I3) {
921 			ret = -ETIME;
922 			goto out;
923 		}
924 	}
925 
926 	ret = 0;
927 off:
928 	hw->pg_state = MEI_PG_OFF;
929 out:
930 	dev->pg_event = MEI_PG_EVENT_IDLE;
931 
932 	dev_dbg(dev->dev, "d0i3 exit ret = %d\n", ret);
933 	return ret;
934 }
935 
936 /**
937  * mei_me_pg_legacy_intr - perform legacy pg processing
938  *			   in interrupt thread handler
939  *
940  * @dev: the device structure
941  */
942 static void mei_me_pg_legacy_intr(struct mei_device *dev)
943 {
944 	struct mei_me_hw *hw = to_me_hw(dev);
945 
946 	if (dev->pg_event != MEI_PG_EVENT_INTR_WAIT)
947 		return;
948 
949 	dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
950 	hw->pg_state = MEI_PG_OFF;
951 	if (waitqueue_active(&dev->wait_pg))
952 		wake_up(&dev->wait_pg);
953 }
954 
955 /**
956  * mei_me_d0i3_intr - perform d0i3 processing in interrupt thread handler
957  *
958  * @dev: the device structure
959  */
960 static void mei_me_d0i3_intr(struct mei_device *dev)
961 {
962 	struct mei_me_hw *hw = to_me_hw(dev);
963 
964 	if (dev->pg_event == MEI_PG_EVENT_INTR_WAIT &&
965 	    (hw->intr_source & H_D0I3C_IS)) {
966 		dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
967 		if (hw->pg_state == MEI_PG_ON) {
968 			hw->pg_state = MEI_PG_OFF;
969 			if (dev->hbm_state != MEI_HBM_IDLE) {
970 				/*
971 				 * force H_RDY because it could be
972 				 * wiped off during PG
973 				 */
974 				dev_dbg(dev->dev, "d0i3 set host ready\n");
975 				mei_me_host_set_ready(dev);
976 			}
977 		} else {
978 			hw->pg_state = MEI_PG_ON;
979 		}
980 
981 		wake_up(&dev->wait_pg);
982 	}
983 
984 	if (hw->pg_state == MEI_PG_ON && (hw->intr_source & H_IS)) {
985 		/*
986 		 * HW sent some data and we are in D0i3, so
987 		 * we got here because of HW initiated exit from D0i3.
988 		 * Start runtime pm resume sequence to exit low power state.
989 		 */
990 		dev_dbg(dev->dev, "d0i3 want resume\n");
991 		mei_hbm_pg_resume(dev);
992 	}
993 }
994 
995 /**
996  * mei_me_pg_intr - perform pg processing in interrupt thread handler
997  *
998  * @dev: the device structure
999  */
1000 static void mei_me_pg_intr(struct mei_device *dev)
1001 {
1002 	struct mei_me_hw *hw = to_me_hw(dev);
1003 
1004 	if (hw->d0i3_supported)
1005 		mei_me_d0i3_intr(dev);
1006 	else
1007 		mei_me_pg_legacy_intr(dev);
1008 }
1009 
1010 /**
1011  * mei_me_pg_enter_sync - perform runtime pm entry procedure
1012  *
1013  * @dev: the device structure
1014  *
1015  * Return: 0 on success an error code otherwise
1016  */
1017 int mei_me_pg_enter_sync(struct mei_device *dev)
1018 {
1019 	struct mei_me_hw *hw = to_me_hw(dev);
1020 
1021 	if (hw->d0i3_supported)
1022 		return mei_me_d0i3_enter_sync(dev);
1023 	else
1024 		return mei_me_pg_legacy_enter_sync(dev);
1025 }
1026 
1027 /**
1028  * mei_me_pg_exit_sync - perform runtime pm exit procedure
1029  *
1030  * @dev: the device structure
1031  *
1032  * Return: 0 on success an error code otherwise
1033  */
1034 int mei_me_pg_exit_sync(struct mei_device *dev)
1035 {
1036 	struct mei_me_hw *hw = to_me_hw(dev);
1037 
1038 	if (hw->d0i3_supported)
1039 		return mei_me_d0i3_exit_sync(dev);
1040 	else
1041 		return mei_me_pg_legacy_exit_sync(dev);
1042 }
1043 
1044 /**
1045  * mei_me_hw_reset - resets fw via mei csr register.
1046  *
1047  * @dev: the device structure
1048  * @intr_enable: if interrupt should be enabled after reset.
1049  *
1050  * Return: 0 on success an error code otherwise
1051  */
1052 static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
1053 {
1054 	struct mei_me_hw *hw = to_me_hw(dev);
1055 	int ret;
1056 	u32 hcsr;
1057 
1058 	if (intr_enable) {
1059 		mei_me_intr_enable(dev);
1060 		if (hw->d0i3_supported) {
1061 			ret = mei_me_d0i3_exit_sync(dev);
1062 			if (ret)
1063 				return ret;
1064 		}
1065 	}
1066 
1067 	pm_runtime_set_active(dev->dev);
1068 
1069 	hcsr = mei_hcsr_read(dev);
1070 	/* H_RST may be found lit before reset is started,
1071 	 * for example if preceding reset flow hasn't completed.
1072 	 * In that case asserting H_RST will be ignored, therefore
1073 	 * we need to clean H_RST bit to start a successful reset sequence.
1074 	 */
1075 	if ((hcsr & H_RST) == H_RST) {
1076 		dev_warn(dev->dev, "H_RST is set = 0x%08X", hcsr);
1077 		hcsr &= ~H_RST;
1078 		mei_hcsr_set(dev, hcsr);
1079 		hcsr = mei_hcsr_read(dev);
1080 	}
1081 
1082 	hcsr |= H_RST | H_IG | H_CSR_IS_MASK;
1083 
1084 	if (!intr_enable)
1085 		hcsr &= ~H_CSR_IE_MASK;
1086 
1087 	dev->recvd_hw_ready = false;
1088 	mei_hcsr_write(dev, hcsr);
1089 
1090 	/*
1091 	 * Host reads the H_CSR once to ensure that the
1092 	 * posted write to H_CSR completes.
1093 	 */
1094 	hcsr = mei_hcsr_read(dev);
1095 
1096 	if ((hcsr & H_RST) == 0)
1097 		dev_warn(dev->dev, "H_RST is not set = 0x%08X", hcsr);
1098 
1099 	if ((hcsr & H_RDY) == H_RDY)
1100 		dev_warn(dev->dev, "H_RDY is not cleared 0x%08X", hcsr);
1101 
1102 	if (!intr_enable) {
1103 		mei_me_hw_reset_release(dev);
1104 		if (hw->d0i3_supported) {
1105 			ret = mei_me_d0i3_enter(dev);
1106 			if (ret)
1107 				return ret;
1108 		}
1109 	}
1110 	return 0;
1111 }
1112 
1113 /**
1114  * mei_me_irq_quick_handler - The ISR of the MEI device
1115  *
1116  * @irq: The irq number
1117  * @dev_id: pointer to the device structure
1118  *
1119  * Return: irqreturn_t
1120  */
1121 irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
1122 {
1123 	struct mei_device *dev = (struct mei_device *)dev_id;
1124 	struct mei_me_hw *hw = to_me_hw(dev);
1125 	u32 hcsr;
1126 
1127 	hcsr = mei_hcsr_read(dev);
1128 	if (!(hcsr & H_CSR_IS_MASK))
1129 		return IRQ_NONE;
1130 
1131 	hw->intr_source = hcsr & H_CSR_IS_MASK;
1132 	dev_dbg(dev->dev, "interrupt source 0x%08X.\n", hw->intr_source);
1133 
1134 	/* clear H_IS and H_D0I3C_IS bits in H_CSR to clear the interrupts */
1135 	mei_hcsr_write(dev, hcsr);
1136 
1137 	return IRQ_WAKE_THREAD;
1138 }
1139 
1140 /**
1141  * mei_me_irq_thread_handler - function called after ISR to handle the interrupt
1142  * processing.
1143  *
1144  * @irq: The irq number
1145  * @dev_id: pointer to the device structure
1146  *
1147  * Return: irqreturn_t
1148  *
1149  */
1150 irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
1151 {
1152 	struct mei_device *dev = (struct mei_device *) dev_id;
1153 	struct mei_cl_cb complete_list;
1154 	s32 slots;
1155 	int rets = 0;
1156 
1157 	dev_dbg(dev->dev, "function called after ISR to handle the interrupt processing.\n");
1158 	/* initialize our complete list */
1159 	mutex_lock(&dev->device_lock);
1160 	mei_io_list_init(&complete_list);
1161 
1162 	/* check if ME wants a reset */
1163 	if (!mei_hw_is_ready(dev) && dev->dev_state != MEI_DEV_RESETTING) {
1164 		dev_warn(dev->dev, "FW not ready: resetting.\n");
1165 		schedule_work(&dev->reset_work);
1166 		goto end;
1167 	}
1168 
1169 	mei_me_pg_intr(dev);
1170 
1171 	/*  check if we need to start the dev */
1172 	if (!mei_host_is_ready(dev)) {
1173 		if (mei_hw_is_ready(dev)) {
1174 			dev_dbg(dev->dev, "we need to start the dev.\n");
1175 			dev->recvd_hw_ready = true;
1176 			wake_up(&dev->wait_hw_ready);
1177 		} else {
1178 			dev_dbg(dev->dev, "Spurious Interrupt\n");
1179 		}
1180 		goto end;
1181 	}
1182 	/* check slots available for reading */
1183 	slots = mei_count_full_read_slots(dev);
1184 	while (slots > 0) {
1185 		dev_dbg(dev->dev, "slots to read = %08x\n", slots);
1186 		rets = mei_irq_read_handler(dev, &complete_list, &slots);
1187 		/* There is a race between ME write and interrupt delivery:
1188 		 * Not all data is always available immediately after the
1189 		 * interrupt, so try to read again on the next interrupt.
1190 		 */
1191 		if (rets == -ENODATA)
1192 			break;
1193 
1194 		if (rets && dev->dev_state != MEI_DEV_RESETTING) {
1195 			dev_err(dev->dev, "mei_irq_read_handler ret = %d.\n",
1196 						rets);
1197 			schedule_work(&dev->reset_work);
1198 			goto end;
1199 		}
1200 	}
1201 
1202 	dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1203 
1204 	/*
1205 	 * During PG handshake only allowed write is the replay to the
1206 	 * PG exit message, so block calling write function
1207 	 * if the pg event is in PG handshake
1208 	 */
1209 	if (dev->pg_event != MEI_PG_EVENT_WAIT &&
1210 	    dev->pg_event != MEI_PG_EVENT_RECEIVED) {
1211 		rets = mei_irq_write_handler(dev, &complete_list);
1212 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1213 	}
1214 
1215 	mei_irq_compl_handler(dev, &complete_list);
1216 
1217 end:
1218 	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
1219 	mutex_unlock(&dev->device_lock);
1220 	return IRQ_HANDLED;
1221 }
1222 
1223 static const struct mei_hw_ops mei_me_hw_ops = {
1224 
1225 	.fw_status = mei_me_fw_status,
1226 	.pg_state  = mei_me_pg_state,
1227 
1228 	.host_is_ready = mei_me_host_is_ready,
1229 
1230 	.hw_is_ready = mei_me_hw_is_ready,
1231 	.hw_reset = mei_me_hw_reset,
1232 	.hw_config = mei_me_hw_config,
1233 	.hw_start = mei_me_hw_start,
1234 
1235 	.pg_in_transition = mei_me_pg_in_transition,
1236 	.pg_is_enabled = mei_me_pg_is_enabled,
1237 
1238 	.intr_clear = mei_me_intr_clear,
1239 	.intr_enable = mei_me_intr_enable,
1240 	.intr_disable = mei_me_intr_disable,
1241 
1242 	.hbuf_free_slots = mei_me_hbuf_empty_slots,
1243 	.hbuf_is_ready = mei_me_hbuf_is_empty,
1244 	.hbuf_max_len = mei_me_hbuf_max_len,
1245 
1246 	.write = mei_me_write_message,
1247 
1248 	.rdbuf_full_slots = mei_me_count_full_read_slots,
1249 	.read_hdr = mei_me_mecbrw_read,
1250 	.read = mei_me_read_slots
1251 };
1252 
1253 static bool mei_me_fw_type_nm(struct pci_dev *pdev)
1254 {
1255 	u32 reg;
1256 
1257 	pci_read_config_dword(pdev, PCI_CFG_HFS_2, &reg);
1258 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_2", PCI_CFG_HFS_2, reg);
1259 	/* make sure that bit 9 (NM) is up and bit 10 (DM) is down */
1260 	return (reg & 0x600) == 0x200;
1261 }
1262 
1263 #define MEI_CFG_FW_NM                           \
1264 	.quirk_probe = mei_me_fw_type_nm
1265 
1266 static bool mei_me_fw_type_sps(struct pci_dev *pdev)
1267 {
1268 	u32 reg;
1269 	unsigned int devfn;
1270 
1271 	/*
1272 	 * Read ME FW Status register to check for SPS Firmware
1273 	 * The SPS FW is only signaled in pci function 0
1274 	 */
1275 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1276 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_1, &reg);
1277 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
1278 	/* if bits [19:16] = 15, running SPS Firmware */
1279 	return (reg & 0xf0000) == 0xf0000;
1280 }
1281 
1282 #define MEI_CFG_FW_SPS                           \
1283 	.quirk_probe = mei_me_fw_type_sps
1284 
1285 
1286 #define MEI_CFG_LEGACY_HFS                      \
1287 	.fw_status.count = 0
1288 
1289 #define MEI_CFG_ICH_HFS                        \
1290 	.fw_status.count = 1,                   \
1291 	.fw_status.status[0] = PCI_CFG_HFS_1
1292 
1293 #define MEI_CFG_PCH_HFS                         \
1294 	.fw_status.count = 2,                   \
1295 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1296 	.fw_status.status[1] = PCI_CFG_HFS_2
1297 
1298 #define MEI_CFG_PCH8_HFS                        \
1299 	.fw_status.count = 6,                   \
1300 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1301 	.fw_status.status[1] = PCI_CFG_HFS_2,   \
1302 	.fw_status.status[2] = PCI_CFG_HFS_3,   \
1303 	.fw_status.status[3] = PCI_CFG_HFS_4,   \
1304 	.fw_status.status[4] = PCI_CFG_HFS_5,   \
1305 	.fw_status.status[5] = PCI_CFG_HFS_6
1306 
1307 /* ICH Legacy devices */
1308 const struct mei_cfg mei_me_legacy_cfg = {
1309 	MEI_CFG_LEGACY_HFS,
1310 };
1311 
1312 /* ICH devices */
1313 const struct mei_cfg mei_me_ich_cfg = {
1314 	MEI_CFG_ICH_HFS,
1315 };
1316 
1317 /* PCH devices */
1318 const struct mei_cfg mei_me_pch_cfg = {
1319 	MEI_CFG_PCH_HFS,
1320 };
1321 
1322 
1323 /* PCH Cougar Point and Patsburg with quirk for Node Manager exclusion */
1324 const struct mei_cfg mei_me_pch_cpt_pbg_cfg = {
1325 	MEI_CFG_PCH_HFS,
1326 	MEI_CFG_FW_NM,
1327 };
1328 
1329 /* PCH8 Lynx Point and newer devices */
1330 const struct mei_cfg mei_me_pch8_cfg = {
1331 	MEI_CFG_PCH8_HFS,
1332 };
1333 
1334 /* PCH8 Lynx Point with quirk for SPS Firmware exclusion */
1335 const struct mei_cfg mei_me_pch8_sps_cfg = {
1336 	MEI_CFG_PCH8_HFS,
1337 	MEI_CFG_FW_SPS,
1338 };
1339 
1340 /**
1341  * mei_me_dev_init - allocates and initializes the mei device structure
1342  *
1343  * @pdev: The pci device structure
1344  * @cfg: per device generation config
1345  *
1346  * Return: The mei_device_device pointer on success, NULL on failure.
1347  */
1348 struct mei_device *mei_me_dev_init(struct pci_dev *pdev,
1349 				   const struct mei_cfg *cfg)
1350 {
1351 	struct mei_device *dev;
1352 	struct mei_me_hw *hw;
1353 
1354 	dev = kzalloc(sizeof(struct mei_device) +
1355 			 sizeof(struct mei_me_hw), GFP_KERNEL);
1356 	if (!dev)
1357 		return NULL;
1358 	hw = to_me_hw(dev);
1359 
1360 	mei_device_init(dev, &pdev->dev, &mei_me_hw_ops);
1361 	hw->cfg = cfg;
1362 	return dev;
1363 }
1364 
1365