xref: /linux/drivers/misc/mei/hw-me.c (revision fbf46565c67c626849c7ce2a326972d3008d2a91)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2003-2022, Intel Corporation. All rights reserved.
4  * Intel Management Engine Interface (Intel MEI) Linux driver
5  */
6 
7 #include <linux/pci.h>
8 
9 #include <linux/kthread.h>
10 #include <linux/interrupt.h>
11 #include <linux/pm_runtime.h>
12 #include <linux/sizes.h>
13 #include <linux/delay.h>
14 
15 #include "mei_dev.h"
16 #include "hbm.h"
17 
18 #include "hw-me.h"
19 #include "hw-me-regs.h"
20 
21 #include "mei-trace.h"
22 
23 /**
24  * mei_me_reg_read - Reads 32bit data from the mei device
25  *
26  * @hw: the me hardware structure
27  * @offset: offset from which to read the data
28  *
29  * Return: register value (u32)
30  */
31 static inline u32 mei_me_reg_read(const struct mei_me_hw *hw,
32 			       unsigned long offset)
33 {
34 	return ioread32(hw->mem_addr + offset);
35 }
36 
37 
38 /**
39  * mei_me_reg_write - Writes 32bit data to the mei device
40  *
41  * @hw: the me hardware structure
42  * @offset: offset from which to write the data
43  * @value: register value to write (u32)
44  */
45 static inline void mei_me_reg_write(const struct mei_me_hw *hw,
46 				 unsigned long offset, u32 value)
47 {
48 	iowrite32(value, hw->mem_addr + offset);
49 }
50 
51 /**
52  * mei_me_mecbrw_read - Reads 32bit data from ME circular buffer
53  *  read window register
54  *
55  * @dev: the device structure
56  *
57  * Return: ME_CB_RW register value (u32)
58  */
59 static inline u32 mei_me_mecbrw_read(const struct mei_device *dev)
60 {
61 	return mei_me_reg_read(to_me_hw(dev), ME_CB_RW);
62 }
63 
64 /**
65  * mei_me_hcbww_write - write 32bit data to the host circular buffer
66  *
67  * @dev: the device structure
68  * @data: 32bit data to be written to the host circular buffer
69  */
70 static inline void mei_me_hcbww_write(struct mei_device *dev, u32 data)
71 {
72 	mei_me_reg_write(to_me_hw(dev), H_CB_WW, data);
73 }
74 
75 /**
76  * mei_me_mecsr_read - Reads 32bit data from the ME CSR
77  *
78  * @dev: the device structure
79  *
80  * Return: ME_CSR_HA register value (u32)
81  */
82 static inline u32 mei_me_mecsr_read(const struct mei_device *dev)
83 {
84 	u32 reg;
85 
86 	reg = mei_me_reg_read(to_me_hw(dev), ME_CSR_HA);
87 	trace_mei_reg_read(dev->dev, "ME_CSR_HA", ME_CSR_HA, reg);
88 
89 	return reg;
90 }
91 
92 /**
93  * mei_hcsr_read - Reads 32bit data from the host CSR
94  *
95  * @dev: the device structure
96  *
97  * Return: H_CSR register value (u32)
98  */
99 static inline u32 mei_hcsr_read(const struct mei_device *dev)
100 {
101 	u32 reg;
102 
103 	reg = mei_me_reg_read(to_me_hw(dev), H_CSR);
104 	trace_mei_reg_read(dev->dev, "H_CSR", H_CSR, reg);
105 
106 	return reg;
107 }
108 
109 /**
110  * mei_hcsr_write - writes H_CSR register to the mei device
111  *
112  * @dev: the device structure
113  * @reg: new register value
114  */
115 static inline void mei_hcsr_write(struct mei_device *dev, u32 reg)
116 {
117 	trace_mei_reg_write(dev->dev, "H_CSR", H_CSR, reg);
118 	mei_me_reg_write(to_me_hw(dev), H_CSR, reg);
119 }
120 
121 /**
122  * mei_hcsr_set - writes H_CSR register to the mei device,
123  * and ignores the H_IS bit for it is write-one-to-zero.
124  *
125  * @dev: the device structure
126  * @reg: new register value
127  */
128 static inline void mei_hcsr_set(struct mei_device *dev, u32 reg)
129 {
130 	reg &= ~H_CSR_IS_MASK;
131 	mei_hcsr_write(dev, reg);
132 }
133 
134 /**
135  * mei_hcsr_set_hig - set host interrupt (set H_IG)
136  *
137  * @dev: the device structure
138  */
139 static inline void mei_hcsr_set_hig(struct mei_device *dev)
140 {
141 	u32 hcsr;
142 
143 	hcsr = mei_hcsr_read(dev) | H_IG;
144 	mei_hcsr_set(dev, hcsr);
145 }
146 
147 /**
148  * mei_me_d0i3c_read - Reads 32bit data from the D0I3C register
149  *
150  * @dev: the device structure
151  *
152  * Return: H_D0I3C register value (u32)
153  */
154 static inline u32 mei_me_d0i3c_read(const struct mei_device *dev)
155 {
156 	u32 reg;
157 
158 	reg = mei_me_reg_read(to_me_hw(dev), H_D0I3C);
159 	trace_mei_reg_read(dev->dev, "H_D0I3C", H_D0I3C, reg);
160 
161 	return reg;
162 }
163 
164 /**
165  * mei_me_d0i3c_write - writes H_D0I3C register to device
166  *
167  * @dev: the device structure
168  * @reg: new register value
169  */
170 static inline void mei_me_d0i3c_write(struct mei_device *dev, u32 reg)
171 {
172 	trace_mei_reg_write(dev->dev, "H_D0I3C", H_D0I3C, reg);
173 	mei_me_reg_write(to_me_hw(dev), H_D0I3C, reg);
174 }
175 
176 /**
177  * mei_me_trc_status - read trc status register
178  *
179  * @dev: mei device
180  * @trc: trc status register value
181  *
182  * Return: 0 on success, error otherwise
183  */
184 static int mei_me_trc_status(struct mei_device *dev, u32 *trc)
185 {
186 	struct mei_me_hw *hw = to_me_hw(dev);
187 
188 	if (!hw->cfg->hw_trc_supported)
189 		return -EOPNOTSUPP;
190 
191 	*trc = mei_me_reg_read(hw, ME_TRC);
192 	trace_mei_reg_read(dev->dev, "ME_TRC", ME_TRC, *trc);
193 
194 	return 0;
195 }
196 
197 /**
198  * mei_me_fw_status - read fw status register from pci config space
199  *
200  * @dev: mei device
201  * @fw_status: fw status register values
202  *
203  * Return: 0 on success, error otherwise
204  */
205 static int mei_me_fw_status(struct mei_device *dev,
206 			    struct mei_fw_status *fw_status)
207 {
208 	struct mei_me_hw *hw = to_me_hw(dev);
209 	const struct mei_fw_status *fw_src = &hw->cfg->fw_status;
210 	int ret;
211 	int i;
212 
213 	if (!fw_status || !hw->read_fws)
214 		return -EINVAL;
215 
216 	fw_status->count = fw_src->count;
217 	for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) {
218 		ret = hw->read_fws(dev, fw_src->status[i],
219 				   &fw_status->status[i]);
220 		trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HFS_X",
221 				       fw_src->status[i],
222 				       fw_status->status[i]);
223 		if (ret)
224 			return ret;
225 	}
226 
227 	return 0;
228 }
229 
230 /**
231  * mei_me_hw_config - configure hw dependent settings
232  *
233  * @dev: mei device
234  *
235  * Return:
236  *  * -EINVAL when read_fws is not set
237  *  * 0 on success
238  *
239  */
240 static int mei_me_hw_config(struct mei_device *dev)
241 {
242 	struct mei_me_hw *hw = to_me_hw(dev);
243 	u32 hcsr, reg;
244 
245 	if (WARN_ON(!hw->read_fws))
246 		return -EINVAL;
247 
248 	/* Doesn't change in runtime */
249 	hcsr = mei_hcsr_read(dev);
250 	hw->hbuf_depth = (hcsr & H_CBD) >> 24;
251 
252 	reg = 0;
253 	hw->read_fws(dev, PCI_CFG_HFS_1, &reg);
254 	trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
255 	hw->d0i3_supported =
256 		((reg & PCI_CFG_HFS_1_D0I3_MSK) == PCI_CFG_HFS_1_D0I3_MSK);
257 
258 	hw->pg_state = MEI_PG_OFF;
259 	if (hw->d0i3_supported) {
260 		reg = mei_me_d0i3c_read(dev);
261 		if (reg & H_D0I3C_I3)
262 			hw->pg_state = MEI_PG_ON;
263 	}
264 
265 	return 0;
266 }
267 
268 /**
269  * mei_me_pg_state  - translate internal pg state
270  *   to the mei power gating state
271  *
272  * @dev:  mei device
273  *
274  * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
275  */
276 static inline enum mei_pg_state mei_me_pg_state(struct mei_device *dev)
277 {
278 	struct mei_me_hw *hw = to_me_hw(dev);
279 
280 	return hw->pg_state;
281 }
282 
283 static inline u32 me_intr_src(u32 hcsr)
284 {
285 	return hcsr & H_CSR_IS_MASK;
286 }
287 
288 /**
289  * me_intr_disable - disables mei device interrupts
290  *      using supplied hcsr register value.
291  *
292  * @dev: the device structure
293  * @hcsr: supplied hcsr register value
294  */
295 static inline void me_intr_disable(struct mei_device *dev, u32 hcsr)
296 {
297 	hcsr &= ~H_CSR_IE_MASK;
298 	mei_hcsr_set(dev, hcsr);
299 }
300 
301 /**
302  * me_intr_clear - clear and stop interrupts
303  *
304  * @dev: the device structure
305  * @hcsr: supplied hcsr register value
306  */
307 static inline void me_intr_clear(struct mei_device *dev, u32 hcsr)
308 {
309 	if (me_intr_src(hcsr))
310 		mei_hcsr_write(dev, hcsr);
311 }
312 
313 /**
314  * mei_me_intr_clear - clear and stop interrupts
315  *
316  * @dev: the device structure
317  */
318 static void mei_me_intr_clear(struct mei_device *dev)
319 {
320 	u32 hcsr = mei_hcsr_read(dev);
321 
322 	me_intr_clear(dev, hcsr);
323 }
324 /**
325  * mei_me_intr_enable - enables mei device interrupts
326  *
327  * @dev: the device structure
328  */
329 static void mei_me_intr_enable(struct mei_device *dev)
330 {
331 	u32 hcsr;
332 
333 	if (mei_me_hw_use_polling(to_me_hw(dev)))
334 		return;
335 
336 	hcsr = mei_hcsr_read(dev) | H_CSR_IE_MASK;
337 	mei_hcsr_set(dev, hcsr);
338 }
339 
340 /**
341  * mei_me_intr_disable - disables mei device interrupts
342  *
343  * @dev: the device structure
344  */
345 static void mei_me_intr_disable(struct mei_device *dev)
346 {
347 	u32 hcsr = mei_hcsr_read(dev);
348 
349 	me_intr_disable(dev, hcsr);
350 }
351 
352 /**
353  * mei_me_synchronize_irq - wait for pending IRQ handlers
354  *
355  * @dev: the device structure
356  */
357 static void mei_me_synchronize_irq(struct mei_device *dev)
358 {
359 	struct mei_me_hw *hw = to_me_hw(dev);
360 
361 	if (mei_me_hw_use_polling(hw))
362 		return;
363 
364 	synchronize_irq(hw->irq);
365 }
366 
367 /**
368  * mei_me_hw_reset_release - release device from the reset
369  *
370  * @dev: the device structure
371  */
372 static void mei_me_hw_reset_release(struct mei_device *dev)
373 {
374 	u32 hcsr = mei_hcsr_read(dev);
375 
376 	hcsr |= H_IG;
377 	hcsr &= ~H_RST;
378 	mei_hcsr_set(dev, hcsr);
379 }
380 
381 /**
382  * mei_me_host_set_ready - enable device
383  *
384  * @dev: mei device
385  */
386 static void mei_me_host_set_ready(struct mei_device *dev)
387 {
388 	u32 hcsr = mei_hcsr_read(dev);
389 
390 	if (!mei_me_hw_use_polling(to_me_hw(dev)))
391 		hcsr |= H_CSR_IE_MASK;
392 
393 	hcsr |=  H_IG | H_RDY;
394 	mei_hcsr_set(dev, hcsr);
395 }
396 
397 /**
398  * mei_me_host_is_ready - check whether the host has turned ready
399  *
400  * @dev: mei device
401  * Return: bool
402  */
403 static bool mei_me_host_is_ready(struct mei_device *dev)
404 {
405 	u32 hcsr = mei_hcsr_read(dev);
406 
407 	return (hcsr & H_RDY) == H_RDY;
408 }
409 
410 /**
411  * mei_me_hw_is_ready - check whether the me(hw) has turned ready
412  *
413  * @dev: mei device
414  * Return: bool
415  */
416 static bool mei_me_hw_is_ready(struct mei_device *dev)
417 {
418 	u32 mecsr = mei_me_mecsr_read(dev);
419 
420 	return (mecsr & ME_RDY_HRA) == ME_RDY_HRA;
421 }
422 
423 /**
424  * mei_me_hw_is_resetting - check whether the me(hw) is in reset
425  *
426  * @dev: mei device
427  * Return: bool
428  */
429 static bool mei_me_hw_is_resetting(struct mei_device *dev)
430 {
431 	u32 mecsr = mei_me_mecsr_read(dev);
432 
433 	return (mecsr & ME_RST_HRA) == ME_RST_HRA;
434 }
435 
436 /**
437  * mei_gsc_pxp_check - check for gsc firmware entering pxp mode
438  *
439  * @dev: the device structure
440  */
441 static void mei_gsc_pxp_check(struct mei_device *dev)
442 {
443 	struct mei_me_hw *hw = to_me_hw(dev);
444 	u32 fwsts5 = 0;
445 
446 	if (dev->pxp_mode == MEI_DEV_PXP_DEFAULT)
447 		return;
448 
449 	hw->read_fws(dev, PCI_CFG_HFS_5, &fwsts5);
450 	trace_mei_pci_cfg_read(dev->dev, "PCI_CFG_HFS_5", PCI_CFG_HFS_5, fwsts5);
451 	if ((fwsts5 & GSC_CFG_HFS_5_BOOT_TYPE_MSK) == GSC_CFG_HFS_5_BOOT_TYPE_PXP) {
452 		dev_dbg(dev->dev, "pxp mode is ready 0x%08x\n", fwsts5);
453 		dev->pxp_mode = MEI_DEV_PXP_READY;
454 	} else {
455 		dev_dbg(dev->dev, "pxp mode is not ready 0x%08x\n", fwsts5);
456 	}
457 }
458 
459 /**
460  * mei_me_hw_ready_wait - wait until the me(hw) has turned ready
461  *  or timeout is reached
462  *
463  * @dev: mei device
464  * Return: 0 on success, error otherwise
465  */
466 static int mei_me_hw_ready_wait(struct mei_device *dev)
467 {
468 	mutex_unlock(&dev->device_lock);
469 	wait_event_timeout(dev->wait_hw_ready,
470 			dev->recvd_hw_ready,
471 			dev->timeouts.hw_ready);
472 	mutex_lock(&dev->device_lock);
473 	if (!dev->recvd_hw_ready) {
474 		dev_err(dev->dev, "wait hw ready failed\n");
475 		return -ETIME;
476 	}
477 
478 	mei_gsc_pxp_check(dev);
479 
480 	mei_me_hw_reset_release(dev);
481 	dev->recvd_hw_ready = false;
482 	return 0;
483 }
484 
485 /**
486  * mei_me_hw_start - hw start routine
487  *
488  * @dev: mei device
489  * Return: 0 on success, error otherwise
490  */
491 static int mei_me_hw_start(struct mei_device *dev)
492 {
493 	int ret = mei_me_hw_ready_wait(dev);
494 
495 	if (ret)
496 		return ret;
497 	dev_dbg(dev->dev, "hw is ready\n");
498 
499 	mei_me_host_set_ready(dev);
500 	return ret;
501 }
502 
503 
504 /**
505  * mei_hbuf_filled_slots - gets number of device filled buffer slots
506  *
507  * @dev: the device structure
508  *
509  * Return: number of filled slots
510  */
511 static unsigned char mei_hbuf_filled_slots(struct mei_device *dev)
512 {
513 	u32 hcsr;
514 	char read_ptr, write_ptr;
515 
516 	hcsr = mei_hcsr_read(dev);
517 
518 	read_ptr = (char) ((hcsr & H_CBRP) >> 8);
519 	write_ptr = (char) ((hcsr & H_CBWP) >> 16);
520 
521 	return (unsigned char) (write_ptr - read_ptr);
522 }
523 
524 /**
525  * mei_me_hbuf_is_empty - checks if host buffer is empty.
526  *
527  * @dev: the device structure
528  *
529  * Return: true if empty, false - otherwise.
530  */
531 static bool mei_me_hbuf_is_empty(struct mei_device *dev)
532 {
533 	return mei_hbuf_filled_slots(dev) == 0;
534 }
535 
536 /**
537  * mei_me_hbuf_empty_slots - counts write empty slots.
538  *
539  * @dev: the device structure
540  *
541  * Return: -EOVERFLOW if overflow, otherwise empty slots count
542  */
543 static int mei_me_hbuf_empty_slots(struct mei_device *dev)
544 {
545 	struct mei_me_hw *hw = to_me_hw(dev);
546 	unsigned char filled_slots, empty_slots;
547 
548 	filled_slots = mei_hbuf_filled_slots(dev);
549 	empty_slots = hw->hbuf_depth - filled_slots;
550 
551 	/* check for overflow */
552 	if (filled_slots > hw->hbuf_depth)
553 		return -EOVERFLOW;
554 
555 	return empty_slots;
556 }
557 
558 /**
559  * mei_me_hbuf_depth - returns depth of the hw buffer.
560  *
561  * @dev: the device structure
562  *
563  * Return: size of hw buffer in slots
564  */
565 static u32 mei_me_hbuf_depth(const struct mei_device *dev)
566 {
567 	struct mei_me_hw *hw = to_me_hw(dev);
568 
569 	return hw->hbuf_depth;
570 }
571 
572 /**
573  * mei_me_hbuf_write - writes a message to host hw buffer.
574  *
575  * @dev: the device structure
576  * @hdr: header of message
577  * @hdr_len: header length in bytes: must be multiplication of a slot (4bytes)
578  * @data: payload
579  * @data_len: payload length in bytes
580  *
581  * Return: 0 if success, < 0 - otherwise.
582  */
583 static int mei_me_hbuf_write(struct mei_device *dev,
584 			     const void *hdr, size_t hdr_len,
585 			     const void *data, size_t data_len)
586 {
587 	unsigned long rem;
588 	unsigned long i;
589 	const u32 *reg_buf;
590 	u32 dw_cnt;
591 	int empty_slots;
592 
593 	if (WARN_ON(!hdr || hdr_len & 0x3))
594 		return -EINVAL;
595 
596 	if (!data && data_len) {
597 		dev_err(dev->dev, "wrong parameters null data with data_len = %zu\n", data_len);
598 		return -EINVAL;
599 	}
600 
601 	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM((struct mei_msg_hdr *)hdr));
602 
603 	empty_slots = mei_hbuf_empty_slots(dev);
604 	dev_dbg(dev->dev, "empty slots = %d.\n", empty_slots);
605 
606 	if (empty_slots < 0)
607 		return -EOVERFLOW;
608 
609 	dw_cnt = mei_data2slots(hdr_len + data_len);
610 	if (dw_cnt > (u32)empty_slots)
611 		return -EMSGSIZE;
612 
613 	reg_buf = hdr;
614 	for (i = 0; i < hdr_len / MEI_SLOT_SIZE; i++)
615 		mei_me_hcbww_write(dev, reg_buf[i]);
616 
617 	reg_buf = data;
618 	for (i = 0; i < data_len / MEI_SLOT_SIZE; i++)
619 		mei_me_hcbww_write(dev, reg_buf[i]);
620 
621 	rem = data_len & 0x3;
622 	if (rem > 0) {
623 		u32 reg = 0;
624 
625 		memcpy(&reg, (const u8 *)data + data_len - rem, rem);
626 		mei_me_hcbww_write(dev, reg);
627 	}
628 
629 	mei_hcsr_set_hig(dev);
630 	if (!mei_me_hw_is_ready(dev))
631 		return -EIO;
632 
633 	return 0;
634 }
635 
636 /**
637  * mei_me_count_full_read_slots - counts read full slots.
638  *
639  * @dev: the device structure
640  *
641  * Return: -EOVERFLOW if overflow, otherwise filled slots count
642  */
643 static int mei_me_count_full_read_slots(struct mei_device *dev)
644 {
645 	u32 me_csr;
646 	char read_ptr, write_ptr;
647 	unsigned char buffer_depth, filled_slots;
648 
649 	me_csr = mei_me_mecsr_read(dev);
650 	buffer_depth = (unsigned char)((me_csr & ME_CBD_HRA) >> 24);
651 	read_ptr = (char) ((me_csr & ME_CBRP_HRA) >> 8);
652 	write_ptr = (char) ((me_csr & ME_CBWP_HRA) >> 16);
653 	filled_slots = (unsigned char) (write_ptr - read_ptr);
654 
655 	/* check for overflow */
656 	if (filled_slots > buffer_depth)
657 		return -EOVERFLOW;
658 
659 	dev_dbg(dev->dev, "filled_slots =%08x\n", filled_slots);
660 	return (int)filled_slots;
661 }
662 
663 /**
664  * mei_me_read_slots - reads a message from mei device.
665  *
666  * @dev: the device structure
667  * @buffer: message buffer will be written
668  * @buffer_length: message size will be read
669  *
670  * Return: always 0
671  */
672 static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
673 			     unsigned long buffer_length)
674 {
675 	u32 *reg_buf = (u32 *)buffer;
676 
677 	for (; buffer_length >= MEI_SLOT_SIZE; buffer_length -= MEI_SLOT_SIZE)
678 		*reg_buf++ = mei_me_mecbrw_read(dev);
679 
680 	if (buffer_length > 0) {
681 		u32 reg = mei_me_mecbrw_read(dev);
682 
683 		memcpy(reg_buf, &reg, buffer_length);
684 	}
685 
686 	mei_hcsr_set_hig(dev);
687 	return 0;
688 }
689 
690 /**
691  * mei_me_pg_set - write pg enter register
692  *
693  * @dev: the device structure
694  */
695 static void mei_me_pg_set(struct mei_device *dev)
696 {
697 	struct mei_me_hw *hw = to_me_hw(dev);
698 	u32 reg;
699 
700 	reg = mei_me_reg_read(hw, H_HPG_CSR);
701 	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
702 
703 	reg |= H_HPG_CSR_PGI;
704 
705 	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
706 	mei_me_reg_write(hw, H_HPG_CSR, reg);
707 }
708 
709 /**
710  * mei_me_pg_unset - write pg exit register
711  *
712  * @dev: the device structure
713  */
714 static void mei_me_pg_unset(struct mei_device *dev)
715 {
716 	struct mei_me_hw *hw = to_me_hw(dev);
717 	u32 reg;
718 
719 	reg = mei_me_reg_read(hw, H_HPG_CSR);
720 	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
721 
722 	WARN(!(reg & H_HPG_CSR_PGI), "PGI is not set\n");
723 
724 	reg |= H_HPG_CSR_PGIHEXR;
725 
726 	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
727 	mei_me_reg_write(hw, H_HPG_CSR, reg);
728 }
729 
730 /**
731  * mei_me_pg_legacy_enter_sync - perform legacy pg entry procedure
732  *
733  * @dev: the device structure
734  *
735  * Return: 0 on success an error code otherwise
736  */
737 static int mei_me_pg_legacy_enter_sync(struct mei_device *dev)
738 {
739 	struct mei_me_hw *hw = to_me_hw(dev);
740 	int ret;
741 
742 	dev->pg_event = MEI_PG_EVENT_WAIT;
743 
744 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
745 	if (ret)
746 		return ret;
747 
748 	mutex_unlock(&dev->device_lock);
749 	wait_event_timeout(dev->wait_pg,
750 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
751 		dev->timeouts.pgi);
752 	mutex_lock(&dev->device_lock);
753 
754 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED) {
755 		mei_me_pg_set(dev);
756 		ret = 0;
757 	} else {
758 		ret = -ETIME;
759 	}
760 
761 	dev->pg_event = MEI_PG_EVENT_IDLE;
762 	hw->pg_state = MEI_PG_ON;
763 
764 	return ret;
765 }
766 
767 /**
768  * mei_me_pg_legacy_exit_sync - perform legacy pg exit procedure
769  *
770  * @dev: the device structure
771  *
772  * Return: 0 on success an error code otherwise
773  */
774 static int mei_me_pg_legacy_exit_sync(struct mei_device *dev)
775 {
776 	struct mei_me_hw *hw = to_me_hw(dev);
777 	int ret;
778 
779 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED)
780 		goto reply;
781 
782 	dev->pg_event = MEI_PG_EVENT_WAIT;
783 
784 	mei_me_pg_unset(dev);
785 
786 	mutex_unlock(&dev->device_lock);
787 	wait_event_timeout(dev->wait_pg,
788 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
789 		dev->timeouts.pgi);
790 	mutex_lock(&dev->device_lock);
791 
792 reply:
793 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
794 		ret = -ETIME;
795 		goto out;
796 	}
797 
798 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
799 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD);
800 	if (ret)
801 		return ret;
802 
803 	mutex_unlock(&dev->device_lock);
804 	wait_event_timeout(dev->wait_pg,
805 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
806 		dev->timeouts.pgi);
807 	mutex_lock(&dev->device_lock);
808 
809 	if (dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED)
810 		ret = 0;
811 	else
812 		ret = -ETIME;
813 
814 out:
815 	dev->pg_event = MEI_PG_EVENT_IDLE;
816 	hw->pg_state = MEI_PG_OFF;
817 
818 	return ret;
819 }
820 
821 /**
822  * mei_me_pg_in_transition - is device now in pg transition
823  *
824  * @dev: the device structure
825  *
826  * Return: true if in pg transition, false otherwise
827  */
828 static bool mei_me_pg_in_transition(struct mei_device *dev)
829 {
830 	return dev->pg_event >= MEI_PG_EVENT_WAIT &&
831 	       dev->pg_event <= MEI_PG_EVENT_INTR_WAIT;
832 }
833 
834 /**
835  * mei_me_pg_is_enabled - detect if PG is supported by HW
836  *
837  * @dev: the device structure
838  *
839  * Return: true is pg supported, false otherwise
840  */
841 static bool mei_me_pg_is_enabled(struct mei_device *dev)
842 {
843 	struct mei_me_hw *hw = to_me_hw(dev);
844 	u32 reg = mei_me_mecsr_read(dev);
845 
846 	if (hw->d0i3_supported)
847 		return true;
848 
849 	if ((reg & ME_PGIC_HRA) == 0)
850 		goto notsupported;
851 
852 	if (!dev->hbm_f_pg_supported)
853 		goto notsupported;
854 
855 	return true;
856 
857 notsupported:
858 	dev_dbg(dev->dev, "pg: not supported: d0i3 = %d HGP = %d hbm version %d.%d ?= %d.%d\n",
859 		hw->d0i3_supported,
860 		!!(reg & ME_PGIC_HRA),
861 		dev->version.major_version,
862 		dev->version.minor_version,
863 		HBM_MAJOR_VERSION_PGI,
864 		HBM_MINOR_VERSION_PGI);
865 
866 	return false;
867 }
868 
869 /**
870  * mei_me_d0i3_set - write d0i3 register bit on mei device.
871  *
872  * @dev: the device structure
873  * @intr: ask for interrupt
874  *
875  * Return: D0I3C register value
876  */
877 static u32 mei_me_d0i3_set(struct mei_device *dev, bool intr)
878 {
879 	u32 reg = mei_me_d0i3c_read(dev);
880 
881 	reg |= H_D0I3C_I3;
882 	if (intr)
883 		reg |= H_D0I3C_IR;
884 	else
885 		reg &= ~H_D0I3C_IR;
886 	mei_me_d0i3c_write(dev, reg);
887 	/* read it to ensure HW consistency */
888 	reg = mei_me_d0i3c_read(dev);
889 	return reg;
890 }
891 
892 /**
893  * mei_me_d0i3_unset - clean d0i3 register bit on mei device.
894  *
895  * @dev: the device structure
896  *
897  * Return: D0I3C register value
898  */
899 static u32 mei_me_d0i3_unset(struct mei_device *dev)
900 {
901 	u32 reg = mei_me_d0i3c_read(dev);
902 
903 	reg &= ~H_D0I3C_I3;
904 	reg |= H_D0I3C_IR;
905 	mei_me_d0i3c_write(dev, reg);
906 	/* read it to ensure HW consistency */
907 	reg = mei_me_d0i3c_read(dev);
908 	return reg;
909 }
910 
911 /**
912  * mei_me_d0i3_enter_sync - perform d0i3 entry procedure
913  *
914  * @dev: the device structure
915  *
916  * Return: 0 on success an error code otherwise
917  */
918 static int mei_me_d0i3_enter_sync(struct mei_device *dev)
919 {
920 	struct mei_me_hw *hw = to_me_hw(dev);
921 	int ret;
922 	u32 reg;
923 
924 	reg = mei_me_d0i3c_read(dev);
925 	if (reg & H_D0I3C_I3) {
926 		/* we are in d0i3, nothing to do */
927 		dev_dbg(dev->dev, "d0i3 set not needed\n");
928 		ret = 0;
929 		goto on;
930 	}
931 
932 	/* PGI entry procedure */
933 	dev->pg_event = MEI_PG_EVENT_WAIT;
934 
935 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
936 	if (ret)
937 		/* FIXME: should we reset here? */
938 		goto out;
939 
940 	mutex_unlock(&dev->device_lock);
941 	wait_event_timeout(dev->wait_pg,
942 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
943 		dev->timeouts.pgi);
944 	mutex_lock(&dev->device_lock);
945 
946 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
947 		ret = -ETIME;
948 		goto out;
949 	}
950 	/* end PGI entry procedure */
951 
952 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
953 
954 	reg = mei_me_d0i3_set(dev, true);
955 	if (!(reg & H_D0I3C_CIP)) {
956 		dev_dbg(dev->dev, "d0i3 enter wait not needed\n");
957 		ret = 0;
958 		goto on;
959 	}
960 
961 	mutex_unlock(&dev->device_lock);
962 	wait_event_timeout(dev->wait_pg,
963 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
964 		dev->timeouts.d0i3);
965 	mutex_lock(&dev->device_lock);
966 
967 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
968 		reg = mei_me_d0i3c_read(dev);
969 		if (!(reg & H_D0I3C_I3)) {
970 			ret = -ETIME;
971 			goto out;
972 		}
973 	}
974 
975 	ret = 0;
976 on:
977 	hw->pg_state = MEI_PG_ON;
978 out:
979 	dev->pg_event = MEI_PG_EVENT_IDLE;
980 	dev_dbg(dev->dev, "d0i3 enter ret = %d\n", ret);
981 	return ret;
982 }
983 
984 /**
985  * mei_me_d0i3_enter - perform d0i3 entry procedure
986  *   no hbm PG handshake
987  *   no waiting for confirmation; runs with interrupts
988  *   disabled
989  *
990  * @dev: the device structure
991  *
992  * Return: 0 on success an error code otherwise
993  */
994 static int mei_me_d0i3_enter(struct mei_device *dev)
995 {
996 	struct mei_me_hw *hw = to_me_hw(dev);
997 	u32 reg;
998 
999 	reg = mei_me_d0i3c_read(dev);
1000 	if (reg & H_D0I3C_I3) {
1001 		/* we are in d0i3, nothing to do */
1002 		dev_dbg(dev->dev, "already d0i3 : set not needed\n");
1003 		goto on;
1004 	}
1005 
1006 	mei_me_d0i3_set(dev, false);
1007 on:
1008 	hw->pg_state = MEI_PG_ON;
1009 	dev->pg_event = MEI_PG_EVENT_IDLE;
1010 	dev_dbg(dev->dev, "d0i3 enter\n");
1011 	return 0;
1012 }
1013 
1014 /**
1015  * mei_me_d0i3_exit_sync - perform d0i3 exit procedure
1016  *
1017  * @dev: the device structure
1018  *
1019  * Return: 0 on success an error code otherwise
1020  */
1021 static int mei_me_d0i3_exit_sync(struct mei_device *dev)
1022 {
1023 	struct mei_me_hw *hw = to_me_hw(dev);
1024 	int ret;
1025 	u32 reg;
1026 
1027 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
1028 
1029 	reg = mei_me_d0i3c_read(dev);
1030 	if (!(reg & H_D0I3C_I3)) {
1031 		/* we are not in d0i3, nothing to do */
1032 		dev_dbg(dev->dev, "d0i3 exit not needed\n");
1033 		ret = 0;
1034 		goto off;
1035 	}
1036 
1037 	reg = mei_me_d0i3_unset(dev);
1038 	if (!(reg & H_D0I3C_CIP)) {
1039 		dev_dbg(dev->dev, "d0i3 exit wait not needed\n");
1040 		ret = 0;
1041 		goto off;
1042 	}
1043 
1044 	mutex_unlock(&dev->device_lock);
1045 	wait_event_timeout(dev->wait_pg,
1046 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
1047 		dev->timeouts.d0i3);
1048 	mutex_lock(&dev->device_lock);
1049 
1050 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
1051 		reg = mei_me_d0i3c_read(dev);
1052 		if (reg & H_D0I3C_I3) {
1053 			ret = -ETIME;
1054 			goto out;
1055 		}
1056 	}
1057 
1058 	ret = 0;
1059 off:
1060 	hw->pg_state = MEI_PG_OFF;
1061 out:
1062 	dev->pg_event = MEI_PG_EVENT_IDLE;
1063 
1064 	dev_dbg(dev->dev, "d0i3 exit ret = %d\n", ret);
1065 	return ret;
1066 }
1067 
1068 /**
1069  * mei_me_pg_legacy_intr - perform legacy pg processing
1070  *			   in interrupt thread handler
1071  *
1072  * @dev: the device structure
1073  */
1074 static void mei_me_pg_legacy_intr(struct mei_device *dev)
1075 {
1076 	struct mei_me_hw *hw = to_me_hw(dev);
1077 
1078 	if (dev->pg_event != MEI_PG_EVENT_INTR_WAIT)
1079 		return;
1080 
1081 	dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
1082 	hw->pg_state = MEI_PG_OFF;
1083 	if (waitqueue_active(&dev->wait_pg))
1084 		wake_up(&dev->wait_pg);
1085 }
1086 
1087 /**
1088  * mei_me_d0i3_intr - perform d0i3 processing in interrupt thread handler
1089  *
1090  * @dev: the device structure
1091  * @intr_source: interrupt source
1092  */
1093 static void mei_me_d0i3_intr(struct mei_device *dev, u32 intr_source)
1094 {
1095 	struct mei_me_hw *hw = to_me_hw(dev);
1096 
1097 	if (dev->pg_event == MEI_PG_EVENT_INTR_WAIT &&
1098 	    (intr_source & H_D0I3C_IS)) {
1099 		dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
1100 		if (hw->pg_state == MEI_PG_ON) {
1101 			hw->pg_state = MEI_PG_OFF;
1102 			if (dev->hbm_state != MEI_HBM_IDLE) {
1103 				/*
1104 				 * force H_RDY because it could be
1105 				 * wiped off during PG
1106 				 */
1107 				dev_dbg(dev->dev, "d0i3 set host ready\n");
1108 				mei_me_host_set_ready(dev);
1109 			}
1110 		} else {
1111 			hw->pg_state = MEI_PG_ON;
1112 		}
1113 
1114 		wake_up(&dev->wait_pg);
1115 	}
1116 
1117 	if (hw->pg_state == MEI_PG_ON && (intr_source & H_IS)) {
1118 		/*
1119 		 * HW sent some data and we are in D0i3, so
1120 		 * we got here because of HW initiated exit from D0i3.
1121 		 * Start runtime pm resume sequence to exit low power state.
1122 		 */
1123 		dev_dbg(dev->dev, "d0i3 want resume\n");
1124 		mei_hbm_pg_resume(dev);
1125 	}
1126 }
1127 
1128 /**
1129  * mei_me_pg_intr - perform pg processing in interrupt thread handler
1130  *
1131  * @dev: the device structure
1132  * @intr_source: interrupt source
1133  */
1134 static void mei_me_pg_intr(struct mei_device *dev, u32 intr_source)
1135 {
1136 	struct mei_me_hw *hw = to_me_hw(dev);
1137 
1138 	if (hw->d0i3_supported)
1139 		mei_me_d0i3_intr(dev, intr_source);
1140 	else
1141 		mei_me_pg_legacy_intr(dev);
1142 }
1143 
1144 /**
1145  * mei_me_pg_enter_sync - perform runtime pm entry procedure
1146  *
1147  * @dev: the device structure
1148  *
1149  * Return: 0 on success an error code otherwise
1150  */
1151 int mei_me_pg_enter_sync(struct mei_device *dev)
1152 {
1153 	struct mei_me_hw *hw = to_me_hw(dev);
1154 
1155 	if (hw->d0i3_supported)
1156 		return mei_me_d0i3_enter_sync(dev);
1157 	else
1158 		return mei_me_pg_legacy_enter_sync(dev);
1159 }
1160 
1161 /**
1162  * mei_me_pg_exit_sync - perform runtime pm exit procedure
1163  *
1164  * @dev: the device structure
1165  *
1166  * Return: 0 on success an error code otherwise
1167  */
1168 int mei_me_pg_exit_sync(struct mei_device *dev)
1169 {
1170 	struct mei_me_hw *hw = to_me_hw(dev);
1171 
1172 	if (hw->d0i3_supported)
1173 		return mei_me_d0i3_exit_sync(dev);
1174 	else
1175 		return mei_me_pg_legacy_exit_sync(dev);
1176 }
1177 
1178 /**
1179  * mei_me_hw_reset - resets fw via mei csr register.
1180  *
1181  * @dev: the device structure
1182  * @intr_enable: if interrupt should be enabled after reset.
1183  *
1184  * Return: 0 on success an error code otherwise
1185  */
1186 static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
1187 {
1188 	struct mei_me_hw *hw = to_me_hw(dev);
1189 	int ret;
1190 	u32 hcsr;
1191 
1192 	if (intr_enable) {
1193 		mei_me_intr_enable(dev);
1194 		if (hw->d0i3_supported) {
1195 			ret = mei_me_d0i3_exit_sync(dev);
1196 			if (ret)
1197 				return ret;
1198 		} else {
1199 			hw->pg_state = MEI_PG_OFF;
1200 		}
1201 	}
1202 
1203 	pm_runtime_set_active(dev->dev);
1204 
1205 	hcsr = mei_hcsr_read(dev);
1206 	/* H_RST may be found lit before reset is started,
1207 	 * for example if preceding reset flow hasn't completed.
1208 	 * In that case asserting H_RST will be ignored, therefore
1209 	 * we need to clean H_RST bit to start a successful reset sequence.
1210 	 */
1211 	if ((hcsr & H_RST) == H_RST) {
1212 		dev_warn(dev->dev, "H_RST is set = 0x%08X", hcsr);
1213 		hcsr &= ~H_RST;
1214 		mei_hcsr_set(dev, hcsr);
1215 		hcsr = mei_hcsr_read(dev);
1216 	}
1217 
1218 	hcsr |= H_RST | H_IG | H_CSR_IS_MASK;
1219 
1220 	if (!intr_enable || mei_me_hw_use_polling(to_me_hw(dev)))
1221 		hcsr &= ~H_CSR_IE_MASK;
1222 
1223 	dev->recvd_hw_ready = false;
1224 	mei_hcsr_write(dev, hcsr);
1225 
1226 	/*
1227 	 * Host reads the H_CSR once to ensure that the
1228 	 * posted write to H_CSR completes.
1229 	 */
1230 	hcsr = mei_hcsr_read(dev);
1231 
1232 	if ((hcsr & H_RST) == 0)
1233 		dev_warn(dev->dev, "H_RST is not set = 0x%08X", hcsr);
1234 
1235 	if ((hcsr & H_RDY) == H_RDY)
1236 		dev_warn(dev->dev, "H_RDY is not cleared 0x%08X", hcsr);
1237 
1238 	if (!intr_enable) {
1239 		mei_me_hw_reset_release(dev);
1240 		if (hw->d0i3_supported) {
1241 			ret = mei_me_d0i3_enter(dev);
1242 			if (ret)
1243 				return ret;
1244 		}
1245 	}
1246 	return 0;
1247 }
1248 
1249 /**
1250  * mei_me_irq_quick_handler - The ISR of the MEI device
1251  *
1252  * @irq: The irq number
1253  * @dev_id: pointer to the device structure
1254  *
1255  * Return: irqreturn_t
1256  */
1257 irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
1258 {
1259 	struct mei_device *dev = (struct mei_device *)dev_id;
1260 	u32 hcsr;
1261 
1262 	hcsr = mei_hcsr_read(dev);
1263 	if (!me_intr_src(hcsr))
1264 		return IRQ_NONE;
1265 
1266 	dev_dbg(dev->dev, "interrupt source 0x%08X\n", me_intr_src(hcsr));
1267 
1268 	/* disable interrupts on device */
1269 	me_intr_disable(dev, hcsr);
1270 	return IRQ_WAKE_THREAD;
1271 }
1272 EXPORT_SYMBOL_GPL(mei_me_irq_quick_handler);
1273 
1274 /**
1275  * mei_me_irq_thread_handler - function called after ISR to handle the interrupt
1276  * processing.
1277  *
1278  * @irq: The irq number
1279  * @dev_id: pointer to the device structure
1280  *
1281  * Return: irqreturn_t
1282  *
1283  */
1284 irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
1285 {
1286 	struct mei_device *dev = (struct mei_device *) dev_id;
1287 	struct list_head cmpl_list;
1288 	s32 slots;
1289 	u32 hcsr;
1290 	int rets = 0;
1291 
1292 	dev_dbg(dev->dev, "function called after ISR to handle the interrupt processing.\n");
1293 	/* initialize our complete list */
1294 	mutex_lock(&dev->device_lock);
1295 
1296 	hcsr = mei_hcsr_read(dev);
1297 	me_intr_clear(dev, hcsr);
1298 
1299 	INIT_LIST_HEAD(&cmpl_list);
1300 
1301 	/* check if ME wants a reset */
1302 	if (!mei_hw_is_ready(dev) && dev->dev_state != MEI_DEV_RESETTING) {
1303 		dev_warn(dev->dev, "FW not ready: resetting: dev_state = %d pxp = %d\n",
1304 			 dev->dev_state, dev->pxp_mode);
1305 		if (dev->dev_state == MEI_DEV_POWERING_DOWN ||
1306 		    dev->dev_state == MEI_DEV_POWER_DOWN)
1307 			mei_cl_all_disconnect(dev);
1308 		else if (dev->dev_state != MEI_DEV_DISABLED)
1309 			schedule_work(&dev->reset_work);
1310 		goto end;
1311 	}
1312 
1313 	if (mei_me_hw_is_resetting(dev))
1314 		mei_hcsr_set_hig(dev);
1315 
1316 	mei_me_pg_intr(dev, me_intr_src(hcsr));
1317 
1318 	/*  check if we need to start the dev */
1319 	if (!mei_host_is_ready(dev)) {
1320 		if (mei_hw_is_ready(dev)) {
1321 			dev_dbg(dev->dev, "we need to start the dev.\n");
1322 			dev->recvd_hw_ready = true;
1323 			wake_up(&dev->wait_hw_ready);
1324 		} else {
1325 			dev_dbg(dev->dev, "Spurious Interrupt\n");
1326 		}
1327 		goto end;
1328 	}
1329 	/* check slots available for reading */
1330 	slots = mei_count_full_read_slots(dev);
1331 	while (slots > 0) {
1332 		dev_dbg(dev->dev, "slots to read = %08x\n", slots);
1333 		rets = mei_irq_read_handler(dev, &cmpl_list, &slots);
1334 		/* There is a race between ME write and interrupt delivery:
1335 		 * Not all data is always available immediately after the
1336 		 * interrupt, so try to read again on the next interrupt.
1337 		 */
1338 		if (rets == -ENODATA)
1339 			break;
1340 
1341 		if (rets) {
1342 			dev_err(dev->dev, "mei_irq_read_handler ret = %d, state = %d.\n",
1343 				rets, dev->dev_state);
1344 			if (dev->dev_state != MEI_DEV_RESETTING &&
1345 			    dev->dev_state != MEI_DEV_DISABLED &&
1346 			    dev->dev_state != MEI_DEV_POWERING_DOWN &&
1347 			    dev->dev_state != MEI_DEV_POWER_DOWN)
1348 				schedule_work(&dev->reset_work);
1349 			goto end;
1350 		}
1351 	}
1352 
1353 	dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1354 
1355 	/*
1356 	 * During PG handshake only allowed write is the replay to the
1357 	 * PG exit message, so block calling write function
1358 	 * if the pg event is in PG handshake
1359 	 */
1360 	if (dev->pg_event != MEI_PG_EVENT_WAIT &&
1361 	    dev->pg_event != MEI_PG_EVENT_RECEIVED) {
1362 		rets = mei_irq_write_handler(dev, &cmpl_list);
1363 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1364 	}
1365 
1366 	mei_irq_compl_handler(dev, &cmpl_list);
1367 
1368 end:
1369 	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
1370 	mei_me_intr_enable(dev);
1371 	mutex_unlock(&dev->device_lock);
1372 	return IRQ_HANDLED;
1373 }
1374 EXPORT_SYMBOL_GPL(mei_me_irq_thread_handler);
1375 
1376 #define MEI_POLLING_TIMEOUT_ACTIVE 100
1377 #define MEI_POLLING_TIMEOUT_IDLE   500
1378 
1379 /**
1380  * mei_me_polling_thread - interrupt register polling thread
1381  *
1382  * The thread monitors the interrupt source register and calls
1383  * mei_me_irq_thread_handler() to handle the firmware
1384  * input.
1385  *
1386  * The function polls in MEI_POLLING_TIMEOUT_ACTIVE timeout
1387  * in case there was an event, in idle case the polling
1388  * time increases yet again by MEI_POLLING_TIMEOUT_ACTIVE
1389  * up to MEI_POLLING_TIMEOUT_IDLE.
1390  *
1391  * @_dev: mei device
1392  *
1393  * Return: always 0
1394  */
1395 int mei_me_polling_thread(void *_dev)
1396 {
1397 	struct mei_device *dev = _dev;
1398 	irqreturn_t irq_ret;
1399 	long polling_timeout = MEI_POLLING_TIMEOUT_ACTIVE;
1400 
1401 	dev_dbg(dev->dev, "kernel thread is running\n");
1402 	while (!kthread_should_stop()) {
1403 		struct mei_me_hw *hw = to_me_hw(dev);
1404 		u32 hcsr;
1405 
1406 		wait_event_timeout(hw->wait_active,
1407 				   hw->is_active || kthread_should_stop(),
1408 				   msecs_to_jiffies(MEI_POLLING_TIMEOUT_IDLE));
1409 
1410 		if (kthread_should_stop())
1411 			break;
1412 
1413 		hcsr = mei_hcsr_read(dev);
1414 		if (me_intr_src(hcsr)) {
1415 			polling_timeout = MEI_POLLING_TIMEOUT_ACTIVE;
1416 			irq_ret = mei_me_irq_thread_handler(1, dev);
1417 			if (irq_ret != IRQ_HANDLED)
1418 				dev_err(dev->dev, "irq_ret %d\n", irq_ret);
1419 		} else {
1420 			/*
1421 			 * Increase timeout by MEI_POLLING_TIMEOUT_ACTIVE
1422 			 * up to MEI_POLLING_TIMEOUT_IDLE
1423 			 */
1424 			polling_timeout = clamp_val(polling_timeout + MEI_POLLING_TIMEOUT_ACTIVE,
1425 						    MEI_POLLING_TIMEOUT_ACTIVE,
1426 						    MEI_POLLING_TIMEOUT_IDLE);
1427 		}
1428 
1429 		schedule_timeout_interruptible(msecs_to_jiffies(polling_timeout));
1430 	}
1431 
1432 	return 0;
1433 }
1434 EXPORT_SYMBOL_GPL(mei_me_polling_thread);
1435 
1436 static const struct mei_hw_ops mei_me_hw_ops = {
1437 
1438 	.trc_status = mei_me_trc_status,
1439 	.fw_status = mei_me_fw_status,
1440 	.pg_state  = mei_me_pg_state,
1441 
1442 	.host_is_ready = mei_me_host_is_ready,
1443 
1444 	.hw_is_ready = mei_me_hw_is_ready,
1445 	.hw_reset = mei_me_hw_reset,
1446 	.hw_config = mei_me_hw_config,
1447 	.hw_start = mei_me_hw_start,
1448 
1449 	.pg_in_transition = mei_me_pg_in_transition,
1450 	.pg_is_enabled = mei_me_pg_is_enabled,
1451 
1452 	.intr_clear = mei_me_intr_clear,
1453 	.intr_enable = mei_me_intr_enable,
1454 	.intr_disable = mei_me_intr_disable,
1455 	.synchronize_irq = mei_me_synchronize_irq,
1456 
1457 	.hbuf_free_slots = mei_me_hbuf_empty_slots,
1458 	.hbuf_is_ready = mei_me_hbuf_is_empty,
1459 	.hbuf_depth = mei_me_hbuf_depth,
1460 
1461 	.write = mei_me_hbuf_write,
1462 
1463 	.rdbuf_full_slots = mei_me_count_full_read_slots,
1464 	.read_hdr = mei_me_mecbrw_read,
1465 	.read = mei_me_read_slots
1466 };
1467 
1468 /**
1469  * mei_me_fw_type_nm() - check for nm sku
1470  *
1471  * Read ME FW Status register to check for the Node Manager (NM) Firmware.
1472  * The NM FW is only signaled in PCI function 0.
1473  * __Note__: Deprecated by PCH8 and newer.
1474  *
1475  * @pdev: pci device
1476  *
1477  * Return: true in case of NM firmware
1478  */
1479 static bool mei_me_fw_type_nm(const struct pci_dev *pdev)
1480 {
1481 	u32 reg;
1482 	unsigned int devfn;
1483 
1484 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1485 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_2, &reg);
1486 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_2", PCI_CFG_HFS_2, reg);
1487 	/* make sure that bit 9 (NM) is up and bit 10 (DM) is down */
1488 	return (reg & 0x600) == 0x200;
1489 }
1490 
1491 #define MEI_CFG_FW_NM                           \
1492 	.quirk_probe = mei_me_fw_type_nm
1493 
1494 /**
1495  * mei_me_fw_type_sps_4() - check for sps 4.0 sku
1496  *
1497  * Read ME FW Status register to check for SPS Firmware.
1498  * The SPS FW is only signaled in the PCI function 0.
1499  * __Note__: Deprecated by SPS 5.0 and newer.
1500  *
1501  * @pdev: pci device
1502  *
1503  * Return: true in case of SPS firmware
1504  */
1505 static bool mei_me_fw_type_sps_4(const struct pci_dev *pdev)
1506 {
1507 	u32 reg;
1508 	unsigned int devfn;
1509 
1510 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1511 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_1, &reg);
1512 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
1513 	return (reg & PCI_CFG_HFS_1_OPMODE_MSK) == PCI_CFG_HFS_1_OPMODE_SPS;
1514 }
1515 
1516 #define MEI_CFG_FW_SPS_4                          \
1517 	.quirk_probe = mei_me_fw_type_sps_4
1518 
1519 /**
1520  * mei_me_fw_type_sps_ign() - check for sps or ign sku
1521  *
1522  * Read ME FW Status register to check for SPS or IGN Firmware.
1523  * The SPS/IGN FW is only signaled in pci function 0
1524  *
1525  * @pdev: pci device
1526  *
1527  * Return: true in case of SPS/IGN firmware
1528  */
1529 static bool mei_me_fw_type_sps_ign(const struct pci_dev *pdev)
1530 {
1531 	u32 reg;
1532 	u32 fw_type;
1533 	unsigned int devfn;
1534 
1535 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1536 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_3, &reg);
1537 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_3", PCI_CFG_HFS_3, reg);
1538 	fw_type = (reg & PCI_CFG_HFS_3_FW_SKU_MSK);
1539 
1540 	dev_dbg(&pdev->dev, "fw type is %d\n", fw_type);
1541 
1542 	return fw_type == PCI_CFG_HFS_3_FW_SKU_IGN ||
1543 	       fw_type == PCI_CFG_HFS_3_FW_SKU_SPS;
1544 }
1545 
1546 #define MEI_CFG_KIND_ITOUCH                     \
1547 	.kind = "itouch"
1548 
1549 #define MEI_CFG_TYPE_GSC                        \
1550 	.kind = "gsc"
1551 
1552 #define MEI_CFG_TYPE_GSCFI                      \
1553 	.kind = "gscfi"
1554 
1555 #define MEI_CFG_FW_SPS_IGN                      \
1556 	.quirk_probe = mei_me_fw_type_sps_ign
1557 
1558 #define MEI_CFG_FW_VER_SUPP                     \
1559 	.fw_ver_supported = 1
1560 
1561 #define MEI_CFG_ICH_HFS                      \
1562 	.fw_status.count = 0
1563 
1564 #define MEI_CFG_ICH10_HFS                        \
1565 	.fw_status.count = 1,                   \
1566 	.fw_status.status[0] = PCI_CFG_HFS_1
1567 
1568 #define MEI_CFG_PCH_HFS                         \
1569 	.fw_status.count = 2,                   \
1570 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1571 	.fw_status.status[1] = PCI_CFG_HFS_2
1572 
1573 #define MEI_CFG_PCH8_HFS                        \
1574 	.fw_status.count = 6,                   \
1575 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1576 	.fw_status.status[1] = PCI_CFG_HFS_2,   \
1577 	.fw_status.status[2] = PCI_CFG_HFS_3,   \
1578 	.fw_status.status[3] = PCI_CFG_HFS_4,   \
1579 	.fw_status.status[4] = PCI_CFG_HFS_5,   \
1580 	.fw_status.status[5] = PCI_CFG_HFS_6
1581 
1582 #define MEI_CFG_DMA_128 \
1583 	.dma_size[DMA_DSCR_HOST] = SZ_128K, \
1584 	.dma_size[DMA_DSCR_DEVICE] = SZ_128K, \
1585 	.dma_size[DMA_DSCR_CTRL] = PAGE_SIZE
1586 
1587 #define MEI_CFG_TRC \
1588 	.hw_trc_supported = 1
1589 
1590 /* ICH Legacy devices */
1591 static const struct mei_cfg mei_me_ich_cfg = {
1592 	MEI_CFG_ICH_HFS,
1593 };
1594 
1595 /* ICH devices */
1596 static const struct mei_cfg mei_me_ich10_cfg = {
1597 	MEI_CFG_ICH10_HFS,
1598 };
1599 
1600 /* PCH6 devices */
1601 static const struct mei_cfg mei_me_pch6_cfg = {
1602 	MEI_CFG_PCH_HFS,
1603 };
1604 
1605 /* PCH7 devices */
1606 static const struct mei_cfg mei_me_pch7_cfg = {
1607 	MEI_CFG_PCH_HFS,
1608 	MEI_CFG_FW_VER_SUPP,
1609 };
1610 
1611 /* PCH Cougar Point and Patsburg with quirk for Node Manager exclusion */
1612 static const struct mei_cfg mei_me_pch_cpt_pbg_cfg = {
1613 	MEI_CFG_PCH_HFS,
1614 	MEI_CFG_FW_VER_SUPP,
1615 	MEI_CFG_FW_NM,
1616 };
1617 
1618 /* PCH8 Lynx Point and newer devices */
1619 static const struct mei_cfg mei_me_pch8_cfg = {
1620 	MEI_CFG_PCH8_HFS,
1621 	MEI_CFG_FW_VER_SUPP,
1622 };
1623 
1624 /* PCH8 Lynx Point and newer devices - iTouch */
1625 static const struct mei_cfg mei_me_pch8_itouch_cfg = {
1626 	MEI_CFG_KIND_ITOUCH,
1627 	MEI_CFG_PCH8_HFS,
1628 	MEI_CFG_FW_VER_SUPP,
1629 };
1630 
1631 /* PCH8 Lynx Point with quirk for SPS Firmware exclusion */
1632 static const struct mei_cfg mei_me_pch8_sps_4_cfg = {
1633 	MEI_CFG_PCH8_HFS,
1634 	MEI_CFG_FW_VER_SUPP,
1635 	MEI_CFG_FW_SPS_4,
1636 };
1637 
1638 /* LBG with quirk for SPS (4.0) Firmware exclusion */
1639 static const struct mei_cfg mei_me_pch12_sps_4_cfg = {
1640 	MEI_CFG_PCH8_HFS,
1641 	MEI_CFG_FW_VER_SUPP,
1642 	MEI_CFG_FW_SPS_4,
1643 };
1644 
1645 /* Cannon Lake and newer devices */
1646 static const struct mei_cfg mei_me_pch12_cfg = {
1647 	MEI_CFG_PCH8_HFS,
1648 	MEI_CFG_FW_VER_SUPP,
1649 	MEI_CFG_DMA_128,
1650 };
1651 
1652 /* Cannon Lake with quirk for SPS 5.0 and newer Firmware exclusion */
1653 static const struct mei_cfg mei_me_pch12_sps_cfg = {
1654 	MEI_CFG_PCH8_HFS,
1655 	MEI_CFG_FW_VER_SUPP,
1656 	MEI_CFG_DMA_128,
1657 	MEI_CFG_FW_SPS_IGN,
1658 };
1659 
1660 /* Cannon Lake itouch with quirk for SPS 5.0 and newer Firmware exclusion
1661  * w/o DMA support.
1662  */
1663 static const struct mei_cfg mei_me_pch12_itouch_sps_cfg = {
1664 	MEI_CFG_KIND_ITOUCH,
1665 	MEI_CFG_PCH8_HFS,
1666 	MEI_CFG_FW_VER_SUPP,
1667 	MEI_CFG_FW_SPS_IGN,
1668 };
1669 
1670 /* Tiger Lake and newer devices */
1671 static const struct mei_cfg mei_me_pch15_cfg = {
1672 	MEI_CFG_PCH8_HFS,
1673 	MEI_CFG_FW_VER_SUPP,
1674 	MEI_CFG_DMA_128,
1675 	MEI_CFG_TRC,
1676 };
1677 
1678 /* Tiger Lake with quirk for SPS 5.0 and newer Firmware exclusion */
1679 static const struct mei_cfg mei_me_pch15_sps_cfg = {
1680 	MEI_CFG_PCH8_HFS,
1681 	MEI_CFG_FW_VER_SUPP,
1682 	MEI_CFG_DMA_128,
1683 	MEI_CFG_TRC,
1684 	MEI_CFG_FW_SPS_IGN,
1685 };
1686 
1687 /* Graphics System Controller */
1688 static const struct mei_cfg mei_me_gsc_cfg = {
1689 	MEI_CFG_TYPE_GSC,
1690 	MEI_CFG_PCH8_HFS,
1691 	MEI_CFG_FW_VER_SUPP,
1692 };
1693 
1694 /* Graphics System Controller Firmware Interface */
1695 static const struct mei_cfg mei_me_gscfi_cfg = {
1696 	MEI_CFG_TYPE_GSCFI,
1697 	MEI_CFG_PCH8_HFS,
1698 	MEI_CFG_FW_VER_SUPP,
1699 };
1700 
1701 /*
1702  * mei_cfg_list - A list of platform platform specific configurations.
1703  * Note: has to be synchronized with  enum mei_cfg_idx.
1704  */
1705 static const struct mei_cfg *const mei_cfg_list[] = {
1706 	[MEI_ME_UNDEF_CFG] = NULL,
1707 	[MEI_ME_ICH_CFG] = &mei_me_ich_cfg,
1708 	[MEI_ME_ICH10_CFG] = &mei_me_ich10_cfg,
1709 	[MEI_ME_PCH6_CFG] = &mei_me_pch6_cfg,
1710 	[MEI_ME_PCH7_CFG] = &mei_me_pch7_cfg,
1711 	[MEI_ME_PCH_CPT_PBG_CFG] = &mei_me_pch_cpt_pbg_cfg,
1712 	[MEI_ME_PCH8_CFG] = &mei_me_pch8_cfg,
1713 	[MEI_ME_PCH8_ITOUCH_CFG] = &mei_me_pch8_itouch_cfg,
1714 	[MEI_ME_PCH8_SPS_4_CFG] = &mei_me_pch8_sps_4_cfg,
1715 	[MEI_ME_PCH12_CFG] = &mei_me_pch12_cfg,
1716 	[MEI_ME_PCH12_SPS_4_CFG] = &mei_me_pch12_sps_4_cfg,
1717 	[MEI_ME_PCH12_SPS_CFG] = &mei_me_pch12_sps_cfg,
1718 	[MEI_ME_PCH12_SPS_ITOUCH_CFG] = &mei_me_pch12_itouch_sps_cfg,
1719 	[MEI_ME_PCH15_CFG] = &mei_me_pch15_cfg,
1720 	[MEI_ME_PCH15_SPS_CFG] = &mei_me_pch15_sps_cfg,
1721 	[MEI_ME_GSC_CFG] = &mei_me_gsc_cfg,
1722 	[MEI_ME_GSCFI_CFG] = &mei_me_gscfi_cfg,
1723 };
1724 
1725 const struct mei_cfg *mei_me_get_cfg(kernel_ulong_t idx)
1726 {
1727 	BUILD_BUG_ON(ARRAY_SIZE(mei_cfg_list) != MEI_ME_NUM_CFG);
1728 
1729 	if (idx >= MEI_ME_NUM_CFG)
1730 		return NULL;
1731 
1732 	return mei_cfg_list[idx];
1733 }
1734 EXPORT_SYMBOL_GPL(mei_me_get_cfg);
1735 
1736 /**
1737  * mei_me_dev_init - allocates and initializes the mei device structure
1738  *
1739  * @parent: device associated with physical device (pci/platform)
1740  * @cfg: per device generation config
1741  * @slow_fw: configure longer timeouts as FW is slow
1742  *
1743  * Return: The mei_device pointer on success, NULL on failure.
1744  */
1745 struct mei_device *mei_me_dev_init(struct device *parent,
1746 				   const struct mei_cfg *cfg, bool slow_fw)
1747 {
1748 	struct mei_device *dev;
1749 	struct mei_me_hw *hw;
1750 	int i;
1751 
1752 	dev = devm_kzalloc(parent, sizeof(*dev) + sizeof(*hw), GFP_KERNEL);
1753 	if (!dev)
1754 		return NULL;
1755 
1756 	hw = to_me_hw(dev);
1757 
1758 	for (i = 0; i < DMA_DSCR_NUM; i++)
1759 		dev->dr_dscr[i].size = cfg->dma_size[i];
1760 
1761 	mei_device_init(dev, parent, slow_fw, &mei_me_hw_ops);
1762 	hw->cfg = cfg;
1763 
1764 	dev->fw_f_fw_ver_supported = cfg->fw_ver_supported;
1765 
1766 	dev->kind = cfg->kind;
1767 
1768 	return dev;
1769 }
1770 EXPORT_SYMBOL_GPL(mei_me_dev_init);
1771