xref: /linux/drivers/misc/mei/hw-me.c (revision 68a052239fc4b351e961f698b824f7654a346091)
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 (!kind_is_gsc(dev) && !kind_is_gscfi(dev))
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 
452 	if ((fwsts5 & GSC_CFG_HFS_5_BOOT_TYPE_MSK) == GSC_CFG_HFS_5_BOOT_TYPE_PXP) {
453 		if (dev->gsc_reset_to_pxp == MEI_DEV_RESET_TO_PXP_DEFAULT)
454 			dev->gsc_reset_to_pxp = MEI_DEV_RESET_TO_PXP_PERFORMED;
455 	} else {
456 		dev->gsc_reset_to_pxp = MEI_DEV_RESET_TO_PXP_DEFAULT;
457 	}
458 
459 	if (dev->pxp_mode == MEI_DEV_PXP_DEFAULT)
460 		return;
461 
462 	if ((fwsts5 & GSC_CFG_HFS_5_BOOT_TYPE_MSK) == GSC_CFG_HFS_5_BOOT_TYPE_PXP) {
463 		dev_dbg(&dev->dev, "pxp mode is ready 0x%08x\n", fwsts5);
464 		dev->pxp_mode = MEI_DEV_PXP_READY;
465 	} else {
466 		dev_dbg(&dev->dev, "pxp mode is not ready 0x%08x\n", fwsts5);
467 	}
468 }
469 
470 /**
471  * mei_me_hw_ready_wait - wait until the me(hw) has turned ready
472  *  or timeout is reached
473  *
474  * @dev: mei device
475  * Return: 0 on success, error otherwise
476  */
477 static int mei_me_hw_ready_wait(struct mei_device *dev)
478 {
479 	mutex_unlock(&dev->device_lock);
480 	wait_event_timeout(dev->wait_hw_ready,
481 			dev->recvd_hw_ready,
482 			dev->timeouts.hw_ready);
483 	mutex_lock(&dev->device_lock);
484 	if (!dev->recvd_hw_ready) {
485 		dev_err(&dev->dev, "wait hw ready failed\n");
486 		return -ETIME;
487 	}
488 
489 	mei_gsc_pxp_check(dev);
490 
491 	mei_me_hw_reset_release(dev);
492 	dev->recvd_hw_ready = false;
493 	return 0;
494 }
495 
496 /**
497  * mei_me_hw_start - hw start routine
498  *
499  * @dev: mei device
500  * Return: 0 on success, error otherwise
501  */
502 static int mei_me_hw_start(struct mei_device *dev)
503 {
504 	int ret = mei_me_hw_ready_wait(dev);
505 
506 	if ((kind_is_gsc(dev) || kind_is_gscfi(dev)) &&
507 	    dev->gsc_reset_to_pxp == MEI_DEV_RESET_TO_PXP_PERFORMED)
508 		dev->gsc_reset_to_pxp = MEI_DEV_RESET_TO_PXP_DONE;
509 	if (ret)
510 		return ret;
511 	dev_dbg(&dev->dev, "hw is ready\n");
512 
513 	mei_me_host_set_ready(dev);
514 	return ret;
515 }
516 
517 
518 /**
519  * mei_hbuf_filled_slots - gets number of device filled buffer slots
520  *
521  * @dev: the device structure
522  *
523  * Return: number of filled slots
524  */
525 static unsigned char mei_hbuf_filled_slots(struct mei_device *dev)
526 {
527 	u32 hcsr;
528 	char read_ptr, write_ptr;
529 
530 	hcsr = mei_hcsr_read(dev);
531 
532 	read_ptr = (char) ((hcsr & H_CBRP) >> 8);
533 	write_ptr = (char) ((hcsr & H_CBWP) >> 16);
534 
535 	return (unsigned char) (write_ptr - read_ptr);
536 }
537 
538 /**
539  * mei_me_hbuf_is_empty - checks if host buffer is empty.
540  *
541  * @dev: the device structure
542  *
543  * Return: true if empty, false - otherwise.
544  */
545 static bool mei_me_hbuf_is_empty(struct mei_device *dev)
546 {
547 	return mei_hbuf_filled_slots(dev) == 0;
548 }
549 
550 /**
551  * mei_me_hbuf_empty_slots - counts write empty slots.
552  *
553  * @dev: the device structure
554  *
555  * Return: -EOVERFLOW if overflow, otherwise empty slots count
556  */
557 static int mei_me_hbuf_empty_slots(struct mei_device *dev)
558 {
559 	struct mei_me_hw *hw = to_me_hw(dev);
560 	unsigned char filled_slots, empty_slots;
561 
562 	filled_slots = mei_hbuf_filled_slots(dev);
563 	empty_slots = hw->hbuf_depth - filled_slots;
564 
565 	/* check for overflow */
566 	if (filled_slots > hw->hbuf_depth)
567 		return -EOVERFLOW;
568 
569 	return empty_slots;
570 }
571 
572 /**
573  * mei_me_hbuf_depth - returns depth of the hw buffer.
574  *
575  * @dev: the device structure
576  *
577  * Return: size of hw buffer in slots
578  */
579 static u32 mei_me_hbuf_depth(const struct mei_device *dev)
580 {
581 	struct mei_me_hw *hw = to_me_hw(dev);
582 
583 	return hw->hbuf_depth;
584 }
585 
586 /**
587  * mei_me_hbuf_write - writes a message to host hw buffer.
588  *
589  * @dev: the device structure
590  * @hdr: header of message
591  * @hdr_len: header length in bytes: must be multiplication of a slot (4bytes)
592  * @data: payload
593  * @data_len: payload length in bytes
594  *
595  * Return: 0 if success, < 0 - otherwise.
596  */
597 static int mei_me_hbuf_write(struct mei_device *dev,
598 			     const void *hdr, size_t hdr_len,
599 			     const void *data, size_t data_len)
600 {
601 	unsigned long rem;
602 	unsigned long i;
603 	const u32 *reg_buf;
604 	u32 dw_cnt;
605 	int empty_slots;
606 
607 	if (WARN_ON(!hdr || hdr_len & 0x3))
608 		return -EINVAL;
609 
610 	if (!data && data_len) {
611 		dev_err(&dev->dev, "wrong parameters null data with data_len = %zu\n", data_len);
612 		return -EINVAL;
613 	}
614 
615 	dev_dbg(&dev->dev, MEI_HDR_FMT, MEI_HDR_PRM((struct mei_msg_hdr *)hdr));
616 
617 	empty_slots = mei_hbuf_empty_slots(dev);
618 	dev_dbg(&dev->dev, "empty slots = %d.\n", empty_slots);
619 
620 	if (empty_slots < 0)
621 		return -EOVERFLOW;
622 
623 	dw_cnt = mei_data2slots(hdr_len + data_len);
624 	if (dw_cnt > (u32)empty_slots)
625 		return -EMSGSIZE;
626 
627 	reg_buf = hdr;
628 	for (i = 0; i < hdr_len / MEI_SLOT_SIZE; i++)
629 		mei_me_hcbww_write(dev, reg_buf[i]);
630 
631 	reg_buf = data;
632 	for (i = 0; i < data_len / MEI_SLOT_SIZE; i++)
633 		mei_me_hcbww_write(dev, reg_buf[i]);
634 
635 	rem = data_len & 0x3;
636 	if (rem > 0) {
637 		u32 reg = 0;
638 
639 		memcpy(&reg, (const u8 *)data + data_len - rem, rem);
640 		mei_me_hcbww_write(dev, reg);
641 	}
642 
643 	mei_hcsr_set_hig(dev);
644 	if (!mei_me_hw_is_ready(dev))
645 		return -EIO;
646 
647 	return 0;
648 }
649 
650 /**
651  * mei_me_count_full_read_slots - counts read full slots.
652  *
653  * @dev: the device structure
654  *
655  * Return: -EOVERFLOW if overflow, otherwise filled slots count
656  */
657 static int mei_me_count_full_read_slots(struct mei_device *dev)
658 {
659 	u32 me_csr;
660 	char read_ptr, write_ptr;
661 	unsigned char buffer_depth, filled_slots;
662 
663 	me_csr = mei_me_mecsr_read(dev);
664 	buffer_depth = (unsigned char)((me_csr & ME_CBD_HRA) >> 24);
665 	read_ptr = (char) ((me_csr & ME_CBRP_HRA) >> 8);
666 	write_ptr = (char) ((me_csr & ME_CBWP_HRA) >> 16);
667 	filled_slots = (unsigned char) (write_ptr - read_ptr);
668 
669 	/* check for overflow */
670 	if (filled_slots > buffer_depth)
671 		return -EOVERFLOW;
672 
673 	dev_dbg(&dev->dev, "filled_slots =%08x\n", filled_slots);
674 	return (int)filled_slots;
675 }
676 
677 /**
678  * mei_me_read_slots - reads a message from mei device.
679  *
680  * @dev: the device structure
681  * @buffer: message buffer will be written
682  * @buffer_length: message size will be read
683  *
684  * Return: always 0
685  */
686 static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
687 			     unsigned long buffer_length)
688 {
689 	u32 *reg_buf = (u32 *)buffer;
690 
691 	for (; buffer_length >= MEI_SLOT_SIZE; buffer_length -= MEI_SLOT_SIZE)
692 		*reg_buf++ = mei_me_mecbrw_read(dev);
693 
694 	if (buffer_length > 0) {
695 		u32 reg = mei_me_mecbrw_read(dev);
696 
697 		memcpy(reg_buf, &reg, buffer_length);
698 	}
699 
700 	mei_hcsr_set_hig(dev);
701 	return 0;
702 }
703 
704 /**
705  * mei_me_pg_set - write pg enter register
706  *
707  * @dev: the device structure
708  */
709 static void mei_me_pg_set(struct mei_device *dev)
710 {
711 	struct mei_me_hw *hw = to_me_hw(dev);
712 	u32 reg;
713 
714 	reg = mei_me_reg_read(hw, H_HPG_CSR);
715 	trace_mei_reg_read(&dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
716 
717 	reg |= H_HPG_CSR_PGI;
718 
719 	trace_mei_reg_write(&dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
720 	mei_me_reg_write(hw, H_HPG_CSR, reg);
721 }
722 
723 /**
724  * mei_me_pg_unset - write pg exit register
725  *
726  * @dev: the device structure
727  */
728 static void mei_me_pg_unset(struct mei_device *dev)
729 {
730 	struct mei_me_hw *hw = to_me_hw(dev);
731 	u32 reg;
732 
733 	reg = mei_me_reg_read(hw, H_HPG_CSR);
734 	trace_mei_reg_read(&dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
735 
736 	WARN(!(reg & H_HPG_CSR_PGI), "PGI is not set\n");
737 
738 	reg |= H_HPG_CSR_PGIHEXR;
739 
740 	trace_mei_reg_write(&dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
741 	mei_me_reg_write(hw, H_HPG_CSR, reg);
742 }
743 
744 /**
745  * mei_me_pg_legacy_enter_sync - perform legacy pg entry procedure
746  *
747  * @dev: the device structure
748  *
749  * Return: 0 on success an error code otherwise
750  */
751 static int mei_me_pg_legacy_enter_sync(struct mei_device *dev)
752 {
753 	struct mei_me_hw *hw = to_me_hw(dev);
754 	int ret;
755 
756 	dev->pg_event = MEI_PG_EVENT_WAIT;
757 
758 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
759 	if (ret)
760 		return ret;
761 
762 	mutex_unlock(&dev->device_lock);
763 	wait_event_timeout(dev->wait_pg,
764 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
765 		dev->timeouts.pgi);
766 	mutex_lock(&dev->device_lock);
767 
768 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED) {
769 		mei_me_pg_set(dev);
770 		ret = 0;
771 	} else {
772 		ret = -ETIME;
773 	}
774 
775 	dev->pg_event = MEI_PG_EVENT_IDLE;
776 	hw->pg_state = MEI_PG_ON;
777 
778 	return ret;
779 }
780 
781 /**
782  * mei_me_pg_legacy_exit_sync - perform legacy pg exit procedure
783  *
784  * @dev: the device structure
785  *
786  * Return: 0 on success an error code otherwise
787  */
788 static int mei_me_pg_legacy_exit_sync(struct mei_device *dev)
789 {
790 	struct mei_me_hw *hw = to_me_hw(dev);
791 	int ret;
792 
793 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED)
794 		goto reply;
795 
796 	dev->pg_event = MEI_PG_EVENT_WAIT;
797 
798 	mei_me_pg_unset(dev);
799 
800 	mutex_unlock(&dev->device_lock);
801 	wait_event_timeout(dev->wait_pg,
802 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
803 		dev->timeouts.pgi);
804 	mutex_lock(&dev->device_lock);
805 
806 reply:
807 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
808 		ret = -ETIME;
809 		goto out;
810 	}
811 
812 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
813 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD);
814 	if (ret)
815 		return ret;
816 
817 	mutex_unlock(&dev->device_lock);
818 	wait_event_timeout(dev->wait_pg,
819 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
820 		dev->timeouts.pgi);
821 	mutex_lock(&dev->device_lock);
822 
823 	if (dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED)
824 		ret = 0;
825 	else
826 		ret = -ETIME;
827 
828 out:
829 	dev->pg_event = MEI_PG_EVENT_IDLE;
830 	hw->pg_state = MEI_PG_OFF;
831 
832 	return ret;
833 }
834 
835 /**
836  * mei_me_pg_in_transition - is device now in pg transition
837  *
838  * @dev: the device structure
839  *
840  * Return: true if in pg transition, false otherwise
841  */
842 static bool mei_me_pg_in_transition(struct mei_device *dev)
843 {
844 	return dev->pg_event >= MEI_PG_EVENT_WAIT &&
845 	       dev->pg_event <= MEI_PG_EVENT_INTR_WAIT;
846 }
847 
848 /**
849  * mei_me_pg_is_enabled - detect if PG is supported by HW
850  *
851  * @dev: the device structure
852  *
853  * Return: true is pg supported, false otherwise
854  */
855 static bool mei_me_pg_is_enabled(struct mei_device *dev)
856 {
857 	struct mei_me_hw *hw = to_me_hw(dev);
858 	u32 reg = mei_me_mecsr_read(dev);
859 
860 	if (hw->d0i3_supported)
861 		return true;
862 
863 	if ((reg & ME_PGIC_HRA) == 0)
864 		goto notsupported;
865 
866 	if (!dev->hbm_f_pg_supported)
867 		goto notsupported;
868 
869 	return true;
870 
871 notsupported:
872 	dev_dbg(&dev->dev, "pg: not supported: d0i3 = %d HGP = %d hbm version %d.%d ?= %d.%d\n",
873 		hw->d0i3_supported,
874 		!!(reg & ME_PGIC_HRA),
875 		dev->version.major_version,
876 		dev->version.minor_version,
877 		HBM_MAJOR_VERSION_PGI,
878 		HBM_MINOR_VERSION_PGI);
879 
880 	return false;
881 }
882 
883 /**
884  * mei_me_d0i3_set - write d0i3 register bit on mei device.
885  *
886  * @dev: the device structure
887  * @intr: ask for interrupt
888  *
889  * Return: D0I3C register value
890  */
891 static u32 mei_me_d0i3_set(struct mei_device *dev, bool intr)
892 {
893 	u32 reg = mei_me_d0i3c_read(dev);
894 
895 	reg |= H_D0I3C_I3;
896 	if (intr)
897 		reg |= H_D0I3C_IR;
898 	else
899 		reg &= ~H_D0I3C_IR;
900 	mei_me_d0i3c_write(dev, reg);
901 	/* read it to ensure HW consistency */
902 	reg = mei_me_d0i3c_read(dev);
903 	return reg;
904 }
905 
906 /**
907  * mei_me_d0i3_unset - clean d0i3 register bit on mei device.
908  *
909  * @dev: the device structure
910  *
911  * Return: D0I3C register value
912  */
913 static u32 mei_me_d0i3_unset(struct mei_device *dev)
914 {
915 	u32 reg = mei_me_d0i3c_read(dev);
916 
917 	reg &= ~H_D0I3C_I3;
918 	reg |= H_D0I3C_IR;
919 	mei_me_d0i3c_write(dev, reg);
920 	/* read it to ensure HW consistency */
921 	reg = mei_me_d0i3c_read(dev);
922 	return reg;
923 }
924 
925 /**
926  * mei_me_d0i3_enter_sync - perform d0i3 entry procedure
927  *
928  * @dev: the device structure
929  *
930  * Return: 0 on success an error code otherwise
931  */
932 static int mei_me_d0i3_enter_sync(struct mei_device *dev)
933 {
934 	struct mei_me_hw *hw = to_me_hw(dev);
935 	int ret;
936 	u32 reg;
937 
938 	reg = mei_me_d0i3c_read(dev);
939 	if (reg & H_D0I3C_I3) {
940 		/* we are in d0i3, nothing to do */
941 		dev_dbg(&dev->dev, "d0i3 set not needed\n");
942 		ret = 0;
943 		goto on;
944 	}
945 
946 	/* PGI entry procedure */
947 	dev->pg_event = MEI_PG_EVENT_WAIT;
948 
949 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
950 	if (ret)
951 		/* FIXME: should we reset here? */
952 		goto out;
953 
954 	mutex_unlock(&dev->device_lock);
955 	wait_event_timeout(dev->wait_pg,
956 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
957 		dev->timeouts.pgi);
958 	mutex_lock(&dev->device_lock);
959 
960 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
961 		ret = -ETIME;
962 		goto out;
963 	}
964 	/* end PGI entry procedure */
965 
966 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
967 
968 	reg = mei_me_d0i3_set(dev, true);
969 	if (!(reg & H_D0I3C_CIP)) {
970 		dev_dbg(&dev->dev, "d0i3 enter wait not needed\n");
971 		ret = 0;
972 		goto on;
973 	}
974 
975 	mutex_unlock(&dev->device_lock);
976 	wait_event_timeout(dev->wait_pg,
977 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
978 		dev->timeouts.d0i3);
979 	mutex_lock(&dev->device_lock);
980 
981 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
982 		reg = mei_me_d0i3c_read(dev);
983 		if (!(reg & H_D0I3C_I3)) {
984 			ret = -ETIME;
985 			goto out;
986 		}
987 	}
988 
989 	ret = 0;
990 on:
991 	hw->pg_state = MEI_PG_ON;
992 out:
993 	dev->pg_event = MEI_PG_EVENT_IDLE;
994 	dev_dbg(&dev->dev, "d0i3 enter ret = %d\n", ret);
995 	return ret;
996 }
997 
998 /**
999  * mei_me_d0i3_enter - perform d0i3 entry procedure
1000  *   no hbm PG handshake
1001  *   no waiting for confirmation; runs with interrupts
1002  *   disabled
1003  *
1004  * @dev: the device structure
1005  *
1006  * Return: 0 on success an error code otherwise
1007  */
1008 static int mei_me_d0i3_enter(struct mei_device *dev)
1009 {
1010 	struct mei_me_hw *hw = to_me_hw(dev);
1011 	u32 reg;
1012 
1013 	reg = mei_me_d0i3c_read(dev);
1014 	if (reg & H_D0I3C_I3) {
1015 		/* we are in d0i3, nothing to do */
1016 		dev_dbg(&dev->dev, "already d0i3 : set not needed\n");
1017 		goto on;
1018 	}
1019 
1020 	mei_me_d0i3_set(dev, false);
1021 on:
1022 	hw->pg_state = MEI_PG_ON;
1023 	dev->pg_event = MEI_PG_EVENT_IDLE;
1024 	dev_dbg(&dev->dev, "d0i3 enter\n");
1025 	return 0;
1026 }
1027 
1028 /**
1029  * mei_me_d0i3_exit_sync - perform d0i3 exit procedure
1030  *
1031  * @dev: the device structure
1032  *
1033  * Return: 0 on success an error code otherwise
1034  */
1035 static int mei_me_d0i3_exit_sync(struct mei_device *dev)
1036 {
1037 	struct mei_me_hw *hw = to_me_hw(dev);
1038 	int ret;
1039 	u32 reg;
1040 
1041 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
1042 
1043 	reg = mei_me_d0i3c_read(dev);
1044 	if (!(reg & H_D0I3C_I3)) {
1045 		/* we are not in d0i3, nothing to do */
1046 		dev_dbg(&dev->dev, "d0i3 exit not needed\n");
1047 		ret = 0;
1048 		goto off;
1049 	}
1050 
1051 	reg = mei_me_d0i3_unset(dev);
1052 	if (!(reg & H_D0I3C_CIP)) {
1053 		dev_dbg(&dev->dev, "d0i3 exit wait not needed\n");
1054 		ret = 0;
1055 		goto off;
1056 	}
1057 
1058 	mutex_unlock(&dev->device_lock);
1059 	wait_event_timeout(dev->wait_pg,
1060 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
1061 		dev->timeouts.d0i3);
1062 	mutex_lock(&dev->device_lock);
1063 
1064 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
1065 		reg = mei_me_d0i3c_read(dev);
1066 		if (reg & H_D0I3C_I3) {
1067 			ret = -ETIME;
1068 			goto out;
1069 		}
1070 	}
1071 
1072 	ret = 0;
1073 off:
1074 	hw->pg_state = MEI_PG_OFF;
1075 out:
1076 	dev->pg_event = MEI_PG_EVENT_IDLE;
1077 
1078 	dev_dbg(&dev->dev, "d0i3 exit ret = %d\n", ret);
1079 	return ret;
1080 }
1081 
1082 /**
1083  * mei_me_pg_legacy_intr - perform legacy pg processing
1084  *			   in interrupt thread handler
1085  *
1086  * @dev: the device structure
1087  */
1088 static void mei_me_pg_legacy_intr(struct mei_device *dev)
1089 {
1090 	struct mei_me_hw *hw = to_me_hw(dev);
1091 
1092 	if (dev->pg_event != MEI_PG_EVENT_INTR_WAIT)
1093 		return;
1094 
1095 	dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
1096 	hw->pg_state = MEI_PG_OFF;
1097 	if (waitqueue_active(&dev->wait_pg))
1098 		wake_up(&dev->wait_pg);
1099 }
1100 
1101 /**
1102  * mei_me_d0i3_intr - perform d0i3 processing in interrupt thread handler
1103  *
1104  * @dev: the device structure
1105  * @intr_source: interrupt source
1106  */
1107 static void mei_me_d0i3_intr(struct mei_device *dev, u32 intr_source)
1108 {
1109 	struct mei_me_hw *hw = to_me_hw(dev);
1110 
1111 	if (dev->pg_event == MEI_PG_EVENT_INTR_WAIT &&
1112 	    (intr_source & H_D0I3C_IS)) {
1113 		dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
1114 		if (hw->pg_state == MEI_PG_ON) {
1115 			hw->pg_state = MEI_PG_OFF;
1116 			if (dev->hbm_state != MEI_HBM_IDLE) {
1117 				/*
1118 				 * force H_RDY because it could be
1119 				 * wiped off during PG
1120 				 */
1121 				dev_dbg(&dev->dev, "d0i3 set host ready\n");
1122 				mei_me_host_set_ready(dev);
1123 			}
1124 		} else {
1125 			hw->pg_state = MEI_PG_ON;
1126 		}
1127 
1128 		wake_up(&dev->wait_pg);
1129 	}
1130 
1131 	if (hw->pg_state == MEI_PG_ON && (intr_source & H_IS)) {
1132 		/*
1133 		 * HW sent some data and we are in D0i3, so
1134 		 * we got here because of HW initiated exit from D0i3.
1135 		 * Start runtime pm resume sequence to exit low power state.
1136 		 */
1137 		dev_dbg(&dev->dev, "d0i3 want resume\n");
1138 		mei_hbm_pg_resume(dev);
1139 	}
1140 }
1141 
1142 /**
1143  * mei_me_pg_intr - perform pg processing in interrupt thread handler
1144  *
1145  * @dev: the device structure
1146  * @intr_source: interrupt source
1147  */
1148 static void mei_me_pg_intr(struct mei_device *dev, u32 intr_source)
1149 {
1150 	struct mei_me_hw *hw = to_me_hw(dev);
1151 
1152 	if (hw->d0i3_supported)
1153 		mei_me_d0i3_intr(dev, intr_source);
1154 	else
1155 		mei_me_pg_legacy_intr(dev);
1156 }
1157 
1158 /**
1159  * mei_me_pg_enter_sync - perform runtime pm entry procedure
1160  *
1161  * @dev: the device structure
1162  *
1163  * Return: 0 on success an error code otherwise
1164  */
1165 int mei_me_pg_enter_sync(struct mei_device *dev)
1166 {
1167 	struct mei_me_hw *hw = to_me_hw(dev);
1168 
1169 	if (hw->d0i3_supported)
1170 		return mei_me_d0i3_enter_sync(dev);
1171 	else
1172 		return mei_me_pg_legacy_enter_sync(dev);
1173 }
1174 
1175 /**
1176  * mei_me_pg_exit_sync - perform runtime pm exit procedure
1177  *
1178  * @dev: the device structure
1179  *
1180  * Return: 0 on success an error code otherwise
1181  */
1182 int mei_me_pg_exit_sync(struct mei_device *dev)
1183 {
1184 	struct mei_me_hw *hw = to_me_hw(dev);
1185 
1186 	if (hw->d0i3_supported)
1187 		return mei_me_d0i3_exit_sync(dev);
1188 	else
1189 		return mei_me_pg_legacy_exit_sync(dev);
1190 }
1191 
1192 /**
1193  * mei_me_hw_reset - resets fw via mei csr register.
1194  *
1195  * @dev: the device structure
1196  * @intr_enable: if interrupt should be enabled after reset.
1197  *
1198  * Return: 0 on success an error code otherwise
1199  */
1200 static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
1201 {
1202 	struct mei_me_hw *hw = to_me_hw(dev);
1203 	int ret;
1204 	u32 hcsr;
1205 
1206 	if (intr_enable) {
1207 		mei_me_intr_enable(dev);
1208 		if (hw->d0i3_supported) {
1209 			ret = mei_me_d0i3_exit_sync(dev);
1210 			if (ret)
1211 				return ret;
1212 		} else {
1213 			hw->pg_state = MEI_PG_OFF;
1214 		}
1215 	}
1216 
1217 	pm_runtime_set_active(dev->parent);
1218 
1219 	hcsr = mei_hcsr_read(dev);
1220 	/* H_RST may be found lit before reset is started,
1221 	 * for example if preceding reset flow hasn't completed.
1222 	 * In that case asserting H_RST will be ignored, therefore
1223 	 * we need to clean H_RST bit to start a successful reset sequence.
1224 	 */
1225 	if ((hcsr & H_RST) == H_RST) {
1226 		dev_warn(&dev->dev, "H_RST is set = 0x%08X", hcsr);
1227 		hcsr &= ~H_RST;
1228 		mei_hcsr_set(dev, hcsr);
1229 		hcsr = mei_hcsr_read(dev);
1230 	}
1231 
1232 	hcsr |= H_RST | H_IG | H_CSR_IS_MASK;
1233 
1234 	if (!intr_enable || mei_me_hw_use_polling(to_me_hw(dev)))
1235 		hcsr &= ~H_CSR_IE_MASK;
1236 
1237 	dev->recvd_hw_ready = false;
1238 	mei_hcsr_write(dev, hcsr);
1239 
1240 	/*
1241 	 * Host reads the H_CSR once to ensure that the
1242 	 * posted write to H_CSR completes.
1243 	 */
1244 	hcsr = mei_hcsr_read(dev);
1245 
1246 	if ((hcsr & H_RST) == 0)
1247 		dev_warn(&dev->dev, "H_RST is not set = 0x%08X", hcsr);
1248 
1249 	if ((hcsr & H_RDY) == H_RDY)
1250 		dev_warn(&dev->dev, "H_RDY is not cleared 0x%08X", hcsr);
1251 
1252 	if (!intr_enable) {
1253 		mei_me_hw_reset_release(dev);
1254 		if (hw->d0i3_supported) {
1255 			ret = mei_me_d0i3_enter(dev);
1256 			if (ret)
1257 				return ret;
1258 		}
1259 	}
1260 	return 0;
1261 }
1262 
1263 /**
1264  * mei_me_irq_quick_handler - The ISR of the MEI device
1265  *
1266  * @irq: The irq number
1267  * @dev_id: pointer to the device structure
1268  *
1269  * Return: irqreturn_t
1270  */
1271 irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
1272 {
1273 	struct mei_device *dev = (struct mei_device *)dev_id;
1274 	u32 hcsr;
1275 
1276 	hcsr = mei_hcsr_read(dev);
1277 	if (!me_intr_src(hcsr))
1278 		return IRQ_NONE;
1279 
1280 	dev_dbg(&dev->dev, "interrupt source 0x%08X\n", me_intr_src(hcsr));
1281 
1282 	/* disable interrupts on device */
1283 	me_intr_disable(dev, hcsr);
1284 	return IRQ_WAKE_THREAD;
1285 }
1286 EXPORT_SYMBOL_GPL(mei_me_irq_quick_handler);
1287 
1288 /**
1289  * mei_me_irq_thread_handler - function called after ISR to handle the interrupt
1290  * processing.
1291  *
1292  * @irq: The irq number
1293  * @dev_id: pointer to the device structure
1294  *
1295  * Return: irqreturn_t
1296  *
1297  */
1298 irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
1299 {
1300 	struct mei_device *dev = (struct mei_device *) dev_id;
1301 	struct list_head cmpl_list;
1302 	s32 slots;
1303 	u32 hcsr;
1304 	int rets = 0;
1305 
1306 	dev_dbg(&dev->dev, "function called after ISR to handle the interrupt processing.\n");
1307 	/* initialize our complete list */
1308 	mutex_lock(&dev->device_lock);
1309 
1310 	hcsr = mei_hcsr_read(dev);
1311 	me_intr_clear(dev, hcsr);
1312 
1313 	INIT_LIST_HEAD(&cmpl_list);
1314 
1315 	/* check if ME wants a reset */
1316 	if (!mei_hw_is_ready(dev) && dev->dev_state != MEI_DEV_RESETTING) {
1317 		if (kind_is_gsc(dev) || kind_is_gscfi(dev)) {
1318 			dev_dbg(&dev->dev, "FW not ready: resetting: dev_state = %d\n",
1319 				dev->dev_state);
1320 		} else {
1321 			dev_warn(&dev->dev, "FW not ready: resetting: dev_state = %d\n",
1322 				 dev->dev_state);
1323 		}
1324 		if (dev->dev_state == MEI_DEV_POWERING_DOWN ||
1325 		    dev->dev_state == MEI_DEV_POWER_DOWN)
1326 			mei_cl_all_disconnect(dev);
1327 		else if (dev->dev_state != MEI_DEV_DISABLED)
1328 			schedule_work(&dev->reset_work);
1329 		goto end;
1330 	}
1331 
1332 	if (mei_me_hw_is_resetting(dev))
1333 		mei_hcsr_set_hig(dev);
1334 
1335 	mei_me_pg_intr(dev, me_intr_src(hcsr));
1336 
1337 	/*  check if we need to start the dev */
1338 	if (!mei_host_is_ready(dev)) {
1339 		if (mei_hw_is_ready(dev)) {
1340 			/* synchronized by dev mutex */
1341 			if (waitqueue_active(&dev->wait_hw_ready)) {
1342 				dev_dbg(&dev->dev, "we need to start the dev.\n");
1343 				dev->recvd_hw_ready = true;
1344 				wake_up(&dev->wait_hw_ready);
1345 			} else if (dev->dev_state != MEI_DEV_UNINITIALIZED &&
1346 				   dev->dev_state != MEI_DEV_POWERING_DOWN &&
1347 				   dev->dev_state != MEI_DEV_POWER_DOWN) {
1348 				dev_dbg(&dev->dev, "Force link reset.\n");
1349 				schedule_work(&dev->reset_work);
1350 			} else {
1351 				dev_dbg(&dev->dev, "Ignore this interrupt in state = %d\n",
1352 					dev->dev_state);
1353 			}
1354 		} else {
1355 			dev_dbg(&dev->dev, "Spurious Interrupt\n");
1356 		}
1357 		goto end;
1358 	}
1359 	/* check slots available for reading */
1360 	slots = mei_count_full_read_slots(dev);
1361 	while (slots > 0) {
1362 		dev_dbg(&dev->dev, "slots to read = %08x\n", slots);
1363 		rets = mei_irq_read_handler(dev, &cmpl_list, &slots);
1364 		/* There is a race between ME write and interrupt delivery:
1365 		 * Not all data is always available immediately after the
1366 		 * interrupt, so try to read again on the next interrupt.
1367 		 */
1368 		if (rets == -ENODATA)
1369 			break;
1370 
1371 		if (rets) {
1372 			dev_err(&dev->dev, "mei_irq_read_handler ret = %d, state = %d.\n",
1373 				rets, dev->dev_state);
1374 			if (dev->dev_state != MEI_DEV_RESETTING &&
1375 			    dev->dev_state != MEI_DEV_DISABLED &&
1376 			    dev->dev_state != MEI_DEV_POWERING_DOWN &&
1377 			    dev->dev_state != MEI_DEV_POWER_DOWN)
1378 				schedule_work(&dev->reset_work);
1379 			goto end;
1380 		}
1381 	}
1382 
1383 	dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1384 
1385 	/*
1386 	 * During PG handshake only allowed write is the replay to the
1387 	 * PG exit message, so block calling write function
1388 	 * if the pg event is in PG handshake
1389 	 */
1390 	if (dev->pg_event != MEI_PG_EVENT_WAIT &&
1391 	    dev->pg_event != MEI_PG_EVENT_RECEIVED) {
1392 		rets = mei_irq_write_handler(dev, &cmpl_list);
1393 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1394 	}
1395 
1396 	mei_irq_compl_handler(dev, &cmpl_list);
1397 
1398 end:
1399 	dev_dbg(&dev->dev, "interrupt thread end ret = %d\n", rets);
1400 	mei_me_intr_enable(dev);
1401 	mutex_unlock(&dev->device_lock);
1402 	return IRQ_HANDLED;
1403 }
1404 EXPORT_SYMBOL_GPL(mei_me_irq_thread_handler);
1405 
1406 #define MEI_POLLING_TIMEOUT_ACTIVE 100
1407 #define MEI_POLLING_TIMEOUT_IDLE   500
1408 
1409 /**
1410  * mei_me_polling_thread - interrupt register polling thread
1411  *
1412  * @_dev: mei device
1413  *
1414  * The thread monitors the interrupt source register and calls
1415  * mei_me_irq_thread_handler() to handle the firmware
1416  * input.
1417  *
1418  * The function polls in MEI_POLLING_TIMEOUT_ACTIVE timeout
1419  * in case there was an event, in idle case the polling
1420  * time increases yet again by MEI_POLLING_TIMEOUT_ACTIVE
1421  * up to MEI_POLLING_TIMEOUT_IDLE.
1422  *
1423  * Return: always 0
1424  */
1425 int mei_me_polling_thread(void *_dev)
1426 {
1427 	struct mei_device *dev = _dev;
1428 	irqreturn_t irq_ret;
1429 	long polling_timeout = MEI_POLLING_TIMEOUT_ACTIVE;
1430 
1431 	dev_dbg(&dev->dev, "kernel thread is running\n");
1432 	while (!kthread_should_stop()) {
1433 		struct mei_me_hw *hw = to_me_hw(dev);
1434 		u32 hcsr;
1435 
1436 		wait_event_timeout(hw->wait_active,
1437 				   hw->is_active || kthread_should_stop(),
1438 				   msecs_to_jiffies(MEI_POLLING_TIMEOUT_IDLE));
1439 
1440 		if (kthread_should_stop())
1441 			break;
1442 
1443 		hcsr = mei_hcsr_read(dev);
1444 		if (me_intr_src(hcsr)) {
1445 			polling_timeout = MEI_POLLING_TIMEOUT_ACTIVE;
1446 			irq_ret = mei_me_irq_thread_handler(1, dev);
1447 			if (irq_ret != IRQ_HANDLED)
1448 				dev_err(&dev->dev, "irq_ret %d\n", irq_ret);
1449 		} else {
1450 			/*
1451 			 * Increase timeout by MEI_POLLING_TIMEOUT_ACTIVE
1452 			 * up to MEI_POLLING_TIMEOUT_IDLE
1453 			 */
1454 			polling_timeout = clamp_val(polling_timeout + MEI_POLLING_TIMEOUT_ACTIVE,
1455 						    MEI_POLLING_TIMEOUT_ACTIVE,
1456 						    MEI_POLLING_TIMEOUT_IDLE);
1457 		}
1458 
1459 		schedule_timeout_interruptible(msecs_to_jiffies(polling_timeout));
1460 	}
1461 
1462 	return 0;
1463 }
1464 EXPORT_SYMBOL_GPL(mei_me_polling_thread);
1465 
1466 static const struct mei_hw_ops mei_me_hw_ops = {
1467 
1468 	.trc_status = mei_me_trc_status,
1469 	.fw_status = mei_me_fw_status,
1470 	.pg_state  = mei_me_pg_state,
1471 
1472 	.host_is_ready = mei_me_host_is_ready,
1473 
1474 	.hw_is_ready = mei_me_hw_is_ready,
1475 	.hw_reset = mei_me_hw_reset,
1476 	.hw_config = mei_me_hw_config,
1477 	.hw_start = mei_me_hw_start,
1478 
1479 	.pg_in_transition = mei_me_pg_in_transition,
1480 	.pg_is_enabled = mei_me_pg_is_enabled,
1481 
1482 	.intr_clear = mei_me_intr_clear,
1483 	.intr_enable = mei_me_intr_enable,
1484 	.intr_disable = mei_me_intr_disable,
1485 	.synchronize_irq = mei_me_synchronize_irq,
1486 
1487 	.hbuf_free_slots = mei_me_hbuf_empty_slots,
1488 	.hbuf_is_ready = mei_me_hbuf_is_empty,
1489 	.hbuf_depth = mei_me_hbuf_depth,
1490 
1491 	.write = mei_me_hbuf_write,
1492 
1493 	.rdbuf_full_slots = mei_me_count_full_read_slots,
1494 	.read_hdr = mei_me_mecbrw_read,
1495 	.read = mei_me_read_slots
1496 };
1497 
1498 /**
1499  * mei_me_fw_type_nm() - check for nm sku
1500  *
1501  * @pdev: pci device
1502  *
1503  * Read ME FW Status register to check for the Node Manager (NM) Firmware.
1504  * The NM FW is only signaled in PCI function 0.
1505  * __Note__: Deprecated by PCH8 and newer.
1506  *
1507  * Return: true in case of NM firmware
1508  */
1509 static bool mei_me_fw_type_nm(const struct pci_dev *pdev)
1510 {
1511 	u32 reg;
1512 	unsigned int devfn;
1513 
1514 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1515 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_2, &reg);
1516 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_2", PCI_CFG_HFS_2, reg);
1517 	/* make sure that bit 9 (NM) is up and bit 10 (DM) is down */
1518 	return (reg & 0x600) == 0x200;
1519 }
1520 
1521 #define MEI_CFG_FW_NM                           \
1522 	.quirk_probe = mei_me_fw_type_nm
1523 
1524 /**
1525  * mei_me_fw_type_sps_4() - check for sps 4.0 sku
1526  *
1527  * @pdev: pci device
1528  *
1529  * Read ME FW Status register to check for SPS Firmware.
1530  * The SPS FW is only signaled in the PCI function 0.
1531  * __Note__: Deprecated by SPS 5.0 and newer.
1532  *
1533  * Return: true in case of SPS firmware
1534  */
1535 static bool mei_me_fw_type_sps_4(const struct pci_dev *pdev)
1536 {
1537 	u32 reg;
1538 	unsigned int devfn;
1539 
1540 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1541 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_1, &reg);
1542 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
1543 	return (reg & PCI_CFG_HFS_1_OPMODE_MSK) == PCI_CFG_HFS_1_OPMODE_SPS;
1544 }
1545 
1546 #define MEI_CFG_FW_SPS_4                          \
1547 	.quirk_probe = mei_me_fw_type_sps_4
1548 
1549 /**
1550  * mei_me_fw_type_sps_ign() - check for sps or ign sku
1551  *
1552  * @pdev: pci device
1553  *
1554  * Read ME FW Status register to check for SPS or IGN Firmware.
1555  * The SPS/IGN FW is only signaled in pci function 0
1556  *
1557  * Return: true in case of SPS/IGN firmware
1558  */
1559 static bool mei_me_fw_type_sps_ign(const struct pci_dev *pdev)
1560 {
1561 	u32 reg;
1562 	u32 fw_type;
1563 	unsigned int devfn;
1564 
1565 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1566 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_3, &reg);
1567 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_3", PCI_CFG_HFS_3, reg);
1568 	fw_type = (reg & PCI_CFG_HFS_3_FW_SKU_MSK);
1569 
1570 	dev_dbg(&pdev->dev, "fw type is %d\n", fw_type);
1571 
1572 	return fw_type == PCI_CFG_HFS_3_FW_SKU_IGN ||
1573 	       fw_type == PCI_CFG_HFS_3_FW_SKU_SPS;
1574 }
1575 
1576 #define MEI_CFG_KIND_ITOUCH                     \
1577 	.kind = "itouch"
1578 
1579 #define MEI_CFG_TYPE_GSC                        \
1580 	.kind = "gsc"
1581 
1582 #define MEI_CFG_TYPE_GSCFI                      \
1583 	.kind = "gscfi"
1584 
1585 #define MEI_CFG_FW_SPS_IGN                      \
1586 	.quirk_probe = mei_me_fw_type_sps_ign
1587 
1588 #define MEI_CFG_FW_VER_SUPP                     \
1589 	.fw_ver_supported = 1
1590 
1591 #define MEI_CFG_ICH_HFS                      \
1592 	.fw_status.count = 0
1593 
1594 #define MEI_CFG_ICH10_HFS                        \
1595 	.fw_status.count = 1,                   \
1596 	.fw_status.status[0] = PCI_CFG_HFS_1
1597 
1598 #define MEI_CFG_PCH_HFS                         \
1599 	.fw_status.count = 2,                   \
1600 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1601 	.fw_status.status[1] = PCI_CFG_HFS_2
1602 
1603 #define MEI_CFG_PCH8_HFS                        \
1604 	.fw_status.count = 6,                   \
1605 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1606 	.fw_status.status[1] = PCI_CFG_HFS_2,   \
1607 	.fw_status.status[2] = PCI_CFG_HFS_3,   \
1608 	.fw_status.status[3] = PCI_CFG_HFS_4,   \
1609 	.fw_status.status[4] = PCI_CFG_HFS_5,   \
1610 	.fw_status.status[5] = PCI_CFG_HFS_6
1611 
1612 #define MEI_CFG_DMA_128 \
1613 	.dma_size[DMA_DSCR_HOST] = SZ_128K, \
1614 	.dma_size[DMA_DSCR_DEVICE] = SZ_128K, \
1615 	.dma_size[DMA_DSCR_CTRL] = PAGE_SIZE
1616 
1617 #define MEI_CFG_TRC \
1618 	.hw_trc_supported = 1
1619 
1620 /* ICH Legacy devices */
1621 static const struct mei_cfg mei_me_ich_cfg = {
1622 	MEI_CFG_ICH_HFS,
1623 };
1624 
1625 /* ICH devices */
1626 static const struct mei_cfg mei_me_ich10_cfg = {
1627 	MEI_CFG_ICH10_HFS,
1628 };
1629 
1630 /* PCH6 devices */
1631 static const struct mei_cfg mei_me_pch6_cfg = {
1632 	MEI_CFG_PCH_HFS,
1633 };
1634 
1635 /* PCH7 devices */
1636 static const struct mei_cfg mei_me_pch7_cfg = {
1637 	MEI_CFG_PCH_HFS,
1638 	MEI_CFG_FW_VER_SUPP,
1639 };
1640 
1641 /* PCH Cougar Point and Patsburg with quirk for Node Manager exclusion */
1642 static const struct mei_cfg mei_me_pch_cpt_pbg_cfg = {
1643 	MEI_CFG_PCH_HFS,
1644 	MEI_CFG_FW_VER_SUPP,
1645 	MEI_CFG_FW_NM,
1646 };
1647 
1648 /* PCH8 Lynx Point and newer devices */
1649 static const struct mei_cfg mei_me_pch8_cfg = {
1650 	MEI_CFG_PCH8_HFS,
1651 	MEI_CFG_FW_VER_SUPP,
1652 };
1653 
1654 /* PCH8 Lynx Point and newer devices - iTouch */
1655 static const struct mei_cfg mei_me_pch8_itouch_cfg = {
1656 	MEI_CFG_KIND_ITOUCH,
1657 	MEI_CFG_PCH8_HFS,
1658 	MEI_CFG_FW_VER_SUPP,
1659 };
1660 
1661 /* PCH8 Lynx Point with quirk for SPS Firmware exclusion */
1662 static const struct mei_cfg mei_me_pch8_sps_4_cfg = {
1663 	MEI_CFG_PCH8_HFS,
1664 	MEI_CFG_FW_VER_SUPP,
1665 	MEI_CFG_FW_SPS_4,
1666 };
1667 
1668 /* LBG with quirk for SPS (4.0) Firmware exclusion */
1669 static const struct mei_cfg mei_me_pch12_sps_4_cfg = {
1670 	MEI_CFG_PCH8_HFS,
1671 	MEI_CFG_FW_VER_SUPP,
1672 	MEI_CFG_FW_SPS_4,
1673 };
1674 
1675 /* Cannon Lake and newer devices */
1676 static const struct mei_cfg mei_me_pch12_cfg = {
1677 	MEI_CFG_PCH8_HFS,
1678 	MEI_CFG_FW_VER_SUPP,
1679 	MEI_CFG_DMA_128,
1680 };
1681 
1682 /* Cannon Lake with quirk for SPS 5.0 and newer Firmware exclusion */
1683 static const struct mei_cfg mei_me_pch12_sps_cfg = {
1684 	MEI_CFG_PCH8_HFS,
1685 	MEI_CFG_FW_VER_SUPP,
1686 	MEI_CFG_DMA_128,
1687 	MEI_CFG_FW_SPS_IGN,
1688 };
1689 
1690 /* Cannon Lake itouch with quirk for SPS 5.0 and newer Firmware exclusion
1691  * w/o DMA support.
1692  */
1693 static const struct mei_cfg mei_me_pch12_itouch_sps_cfg = {
1694 	MEI_CFG_KIND_ITOUCH,
1695 	MEI_CFG_PCH8_HFS,
1696 	MEI_CFG_FW_VER_SUPP,
1697 	MEI_CFG_FW_SPS_IGN,
1698 };
1699 
1700 /* Tiger Lake and newer devices */
1701 static const struct mei_cfg mei_me_pch15_cfg = {
1702 	MEI_CFG_PCH8_HFS,
1703 	MEI_CFG_FW_VER_SUPP,
1704 	MEI_CFG_DMA_128,
1705 	MEI_CFG_TRC,
1706 };
1707 
1708 /* Tiger Lake with quirk for SPS 5.0 and newer Firmware exclusion */
1709 static const struct mei_cfg mei_me_pch15_sps_cfg = {
1710 	MEI_CFG_PCH8_HFS,
1711 	MEI_CFG_FW_VER_SUPP,
1712 	MEI_CFG_DMA_128,
1713 	MEI_CFG_TRC,
1714 	MEI_CFG_FW_SPS_IGN,
1715 };
1716 
1717 /* Graphics System Controller */
1718 static const struct mei_cfg mei_me_gsc_cfg = {
1719 	MEI_CFG_TYPE_GSC,
1720 	MEI_CFG_PCH8_HFS,
1721 	MEI_CFG_FW_VER_SUPP,
1722 };
1723 
1724 /* Graphics System Controller Firmware Interface */
1725 static const struct mei_cfg mei_me_gscfi_cfg = {
1726 	MEI_CFG_TYPE_GSCFI,
1727 	MEI_CFG_PCH8_HFS,
1728 	MEI_CFG_FW_VER_SUPP,
1729 };
1730 
1731 /*
1732  * mei_cfg_list - A list of platform platform specific configurations.
1733  * Note: has to be synchronized with  enum mei_cfg_idx.
1734  */
1735 static const struct mei_cfg *const mei_cfg_list[] = {
1736 	[MEI_ME_UNDEF_CFG] = NULL,
1737 	[MEI_ME_ICH_CFG] = &mei_me_ich_cfg,
1738 	[MEI_ME_ICH10_CFG] = &mei_me_ich10_cfg,
1739 	[MEI_ME_PCH6_CFG] = &mei_me_pch6_cfg,
1740 	[MEI_ME_PCH7_CFG] = &mei_me_pch7_cfg,
1741 	[MEI_ME_PCH_CPT_PBG_CFG] = &mei_me_pch_cpt_pbg_cfg,
1742 	[MEI_ME_PCH8_CFG] = &mei_me_pch8_cfg,
1743 	[MEI_ME_PCH8_ITOUCH_CFG] = &mei_me_pch8_itouch_cfg,
1744 	[MEI_ME_PCH8_SPS_4_CFG] = &mei_me_pch8_sps_4_cfg,
1745 	[MEI_ME_PCH12_CFG] = &mei_me_pch12_cfg,
1746 	[MEI_ME_PCH12_SPS_4_CFG] = &mei_me_pch12_sps_4_cfg,
1747 	[MEI_ME_PCH12_SPS_CFG] = &mei_me_pch12_sps_cfg,
1748 	[MEI_ME_PCH12_SPS_ITOUCH_CFG] = &mei_me_pch12_itouch_sps_cfg,
1749 	[MEI_ME_PCH15_CFG] = &mei_me_pch15_cfg,
1750 	[MEI_ME_PCH15_SPS_CFG] = &mei_me_pch15_sps_cfg,
1751 	[MEI_ME_GSC_CFG] = &mei_me_gsc_cfg,
1752 	[MEI_ME_GSCFI_CFG] = &mei_me_gscfi_cfg,
1753 };
1754 
1755 const struct mei_cfg *mei_me_get_cfg(kernel_ulong_t idx)
1756 {
1757 	BUILD_BUG_ON(ARRAY_SIZE(mei_cfg_list) != MEI_ME_NUM_CFG);
1758 
1759 	if (idx >= MEI_ME_NUM_CFG)
1760 		return NULL;
1761 
1762 	return mei_cfg_list[idx];
1763 }
1764 EXPORT_SYMBOL_GPL(mei_me_get_cfg);
1765 
1766 /**
1767  * mei_me_dev_init - allocates and initializes the mei device structure
1768  *
1769  * @parent: device associated with physical device (pci/platform)
1770  * @cfg: per device generation config
1771  * @slow_fw: configure longer timeouts as FW is slow
1772  *
1773  * Return: The mei_device pointer on success, NULL on failure.
1774  */
1775 struct mei_device *mei_me_dev_init(struct device *parent,
1776 				   const struct mei_cfg *cfg, bool slow_fw)
1777 {
1778 	struct mei_device *dev;
1779 	struct mei_me_hw *hw;
1780 	int i;
1781 
1782 	dev = kzalloc(sizeof(*dev) + sizeof(*hw), GFP_KERNEL);
1783 	if (!dev)
1784 		return NULL;
1785 
1786 	hw = to_me_hw(dev);
1787 
1788 	for (i = 0; i < DMA_DSCR_NUM; i++)
1789 		dev->dr_dscr[i].size = cfg->dma_size[i];
1790 
1791 	mei_device_init(dev, parent, slow_fw, &mei_me_hw_ops);
1792 	hw->cfg = cfg;
1793 
1794 	dev->fw_f_fw_ver_supported = cfg->fw_ver_supported;
1795 
1796 	dev->kind = cfg->kind;
1797 
1798 	return dev;
1799 }
1800 EXPORT_SYMBOL_GPL(mei_me_dev_init);
1801