xref: /linux/drivers/misc/mei/hw-me.c (revision 2da68a77)
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 || !data || hdr_len & 0x3))
594 		return -EINVAL;
595 
596 	dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM((struct mei_msg_hdr *)hdr));
597 
598 	empty_slots = mei_hbuf_empty_slots(dev);
599 	dev_dbg(dev->dev, "empty slots = %d.\n", empty_slots);
600 
601 	if (empty_slots < 0)
602 		return -EOVERFLOW;
603 
604 	dw_cnt = mei_data2slots(hdr_len + data_len);
605 	if (dw_cnt > (u32)empty_slots)
606 		return -EMSGSIZE;
607 
608 	reg_buf = hdr;
609 	for (i = 0; i < hdr_len / MEI_SLOT_SIZE; i++)
610 		mei_me_hcbww_write(dev, reg_buf[i]);
611 
612 	reg_buf = data;
613 	for (i = 0; i < data_len / MEI_SLOT_SIZE; i++)
614 		mei_me_hcbww_write(dev, reg_buf[i]);
615 
616 	rem = data_len & 0x3;
617 	if (rem > 0) {
618 		u32 reg = 0;
619 
620 		memcpy(&reg, (const u8 *)data + data_len - rem, rem);
621 		mei_me_hcbww_write(dev, reg);
622 	}
623 
624 	mei_hcsr_set_hig(dev);
625 	if (!mei_me_hw_is_ready(dev))
626 		return -EIO;
627 
628 	return 0;
629 }
630 
631 /**
632  * mei_me_count_full_read_slots - counts read full slots.
633  *
634  * @dev: the device structure
635  *
636  * Return: -EOVERFLOW if overflow, otherwise filled slots count
637  */
638 static int mei_me_count_full_read_slots(struct mei_device *dev)
639 {
640 	u32 me_csr;
641 	char read_ptr, write_ptr;
642 	unsigned char buffer_depth, filled_slots;
643 
644 	me_csr = mei_me_mecsr_read(dev);
645 	buffer_depth = (unsigned char)((me_csr & ME_CBD_HRA) >> 24);
646 	read_ptr = (char) ((me_csr & ME_CBRP_HRA) >> 8);
647 	write_ptr = (char) ((me_csr & ME_CBWP_HRA) >> 16);
648 	filled_slots = (unsigned char) (write_ptr - read_ptr);
649 
650 	/* check for overflow */
651 	if (filled_slots > buffer_depth)
652 		return -EOVERFLOW;
653 
654 	dev_dbg(dev->dev, "filled_slots =%08x\n", filled_slots);
655 	return (int)filled_slots;
656 }
657 
658 /**
659  * mei_me_read_slots - reads a message from mei device.
660  *
661  * @dev: the device structure
662  * @buffer: message buffer will be written
663  * @buffer_length: message size will be read
664  *
665  * Return: always 0
666  */
667 static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer,
668 			     unsigned long buffer_length)
669 {
670 	u32 *reg_buf = (u32 *)buffer;
671 
672 	for (; buffer_length >= MEI_SLOT_SIZE; buffer_length -= MEI_SLOT_SIZE)
673 		*reg_buf++ = mei_me_mecbrw_read(dev);
674 
675 	if (buffer_length > 0) {
676 		u32 reg = mei_me_mecbrw_read(dev);
677 
678 		memcpy(reg_buf, &reg, buffer_length);
679 	}
680 
681 	mei_hcsr_set_hig(dev);
682 	return 0;
683 }
684 
685 /**
686  * mei_me_pg_set - write pg enter register
687  *
688  * @dev: the device structure
689  */
690 static void mei_me_pg_set(struct mei_device *dev)
691 {
692 	struct mei_me_hw *hw = to_me_hw(dev);
693 	u32 reg;
694 
695 	reg = mei_me_reg_read(hw, H_HPG_CSR);
696 	trace_mei_reg_read(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
697 
698 	reg |= H_HPG_CSR_PGI;
699 
700 	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
701 	mei_me_reg_write(hw, H_HPG_CSR, reg);
702 }
703 
704 /**
705  * mei_me_pg_unset - write pg exit register
706  *
707  * @dev: the device structure
708  */
709 static void mei_me_pg_unset(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 	WARN(!(reg & H_HPG_CSR_PGI), "PGI is not set\n");
718 
719 	reg |= H_HPG_CSR_PGIHEXR;
720 
721 	trace_mei_reg_write(dev->dev, "H_HPG_CSR", H_HPG_CSR, reg);
722 	mei_me_reg_write(hw, H_HPG_CSR, reg);
723 }
724 
725 /**
726  * mei_me_pg_legacy_enter_sync - perform legacy pg entry procedure
727  *
728  * @dev: the device structure
729  *
730  * Return: 0 on success an error code otherwise
731  */
732 static int mei_me_pg_legacy_enter_sync(struct mei_device *dev)
733 {
734 	struct mei_me_hw *hw = to_me_hw(dev);
735 	int ret;
736 
737 	dev->pg_event = MEI_PG_EVENT_WAIT;
738 
739 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
740 	if (ret)
741 		return ret;
742 
743 	mutex_unlock(&dev->device_lock);
744 	wait_event_timeout(dev->wait_pg,
745 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
746 		dev->timeouts.pgi);
747 	mutex_lock(&dev->device_lock);
748 
749 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED) {
750 		mei_me_pg_set(dev);
751 		ret = 0;
752 	} else {
753 		ret = -ETIME;
754 	}
755 
756 	dev->pg_event = MEI_PG_EVENT_IDLE;
757 	hw->pg_state = MEI_PG_ON;
758 
759 	return ret;
760 }
761 
762 /**
763  * mei_me_pg_legacy_exit_sync - perform legacy pg exit procedure
764  *
765  * @dev: the device structure
766  *
767  * Return: 0 on success an error code otherwise
768  */
769 static int mei_me_pg_legacy_exit_sync(struct mei_device *dev)
770 {
771 	struct mei_me_hw *hw = to_me_hw(dev);
772 	int ret;
773 
774 	if (dev->pg_event == MEI_PG_EVENT_RECEIVED)
775 		goto reply;
776 
777 	dev->pg_event = MEI_PG_EVENT_WAIT;
778 
779 	mei_me_pg_unset(dev);
780 
781 	mutex_unlock(&dev->device_lock);
782 	wait_event_timeout(dev->wait_pg,
783 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
784 		dev->timeouts.pgi);
785 	mutex_lock(&dev->device_lock);
786 
787 reply:
788 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
789 		ret = -ETIME;
790 		goto out;
791 	}
792 
793 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
794 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD);
795 	if (ret)
796 		return ret;
797 
798 	mutex_unlock(&dev->device_lock);
799 	wait_event_timeout(dev->wait_pg,
800 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
801 		dev->timeouts.pgi);
802 	mutex_lock(&dev->device_lock);
803 
804 	if (dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED)
805 		ret = 0;
806 	else
807 		ret = -ETIME;
808 
809 out:
810 	dev->pg_event = MEI_PG_EVENT_IDLE;
811 	hw->pg_state = MEI_PG_OFF;
812 
813 	return ret;
814 }
815 
816 /**
817  * mei_me_pg_in_transition - is device now in pg transition
818  *
819  * @dev: the device structure
820  *
821  * Return: true if in pg transition, false otherwise
822  */
823 static bool mei_me_pg_in_transition(struct mei_device *dev)
824 {
825 	return dev->pg_event >= MEI_PG_EVENT_WAIT &&
826 	       dev->pg_event <= MEI_PG_EVENT_INTR_WAIT;
827 }
828 
829 /**
830  * mei_me_pg_is_enabled - detect if PG is supported by HW
831  *
832  * @dev: the device structure
833  *
834  * Return: true is pg supported, false otherwise
835  */
836 static bool mei_me_pg_is_enabled(struct mei_device *dev)
837 {
838 	struct mei_me_hw *hw = to_me_hw(dev);
839 	u32 reg = mei_me_mecsr_read(dev);
840 
841 	if (hw->d0i3_supported)
842 		return true;
843 
844 	if ((reg & ME_PGIC_HRA) == 0)
845 		goto notsupported;
846 
847 	if (!dev->hbm_f_pg_supported)
848 		goto notsupported;
849 
850 	return true;
851 
852 notsupported:
853 	dev_dbg(dev->dev, "pg: not supported: d0i3 = %d HGP = %d hbm version %d.%d ?= %d.%d\n",
854 		hw->d0i3_supported,
855 		!!(reg & ME_PGIC_HRA),
856 		dev->version.major_version,
857 		dev->version.minor_version,
858 		HBM_MAJOR_VERSION_PGI,
859 		HBM_MINOR_VERSION_PGI);
860 
861 	return false;
862 }
863 
864 /**
865  * mei_me_d0i3_set - write d0i3 register bit on mei device.
866  *
867  * @dev: the device structure
868  * @intr: ask for interrupt
869  *
870  * Return: D0I3C register value
871  */
872 static u32 mei_me_d0i3_set(struct mei_device *dev, bool intr)
873 {
874 	u32 reg = mei_me_d0i3c_read(dev);
875 
876 	reg |= H_D0I3C_I3;
877 	if (intr)
878 		reg |= H_D0I3C_IR;
879 	else
880 		reg &= ~H_D0I3C_IR;
881 	mei_me_d0i3c_write(dev, reg);
882 	/* read it to ensure HW consistency */
883 	reg = mei_me_d0i3c_read(dev);
884 	return reg;
885 }
886 
887 /**
888  * mei_me_d0i3_unset - clean d0i3 register bit on mei device.
889  *
890  * @dev: the device structure
891  *
892  * Return: D0I3C register value
893  */
894 static u32 mei_me_d0i3_unset(struct mei_device *dev)
895 {
896 	u32 reg = mei_me_d0i3c_read(dev);
897 
898 	reg &= ~H_D0I3C_I3;
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_enter_sync - perform d0i3 entry procedure
908  *
909  * @dev: the device structure
910  *
911  * Return: 0 on success an error code otherwise
912  */
913 static int mei_me_d0i3_enter_sync(struct mei_device *dev)
914 {
915 	struct mei_me_hw *hw = to_me_hw(dev);
916 	int ret;
917 	u32 reg;
918 
919 	reg = mei_me_d0i3c_read(dev);
920 	if (reg & H_D0I3C_I3) {
921 		/* we are in d0i3, nothing to do */
922 		dev_dbg(dev->dev, "d0i3 set not needed\n");
923 		ret = 0;
924 		goto on;
925 	}
926 
927 	/* PGI entry procedure */
928 	dev->pg_event = MEI_PG_EVENT_WAIT;
929 
930 	ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD);
931 	if (ret)
932 		/* FIXME: should we reset here? */
933 		goto out;
934 
935 	mutex_unlock(&dev->device_lock);
936 	wait_event_timeout(dev->wait_pg,
937 		dev->pg_event == MEI_PG_EVENT_RECEIVED,
938 		dev->timeouts.pgi);
939 	mutex_lock(&dev->device_lock);
940 
941 	if (dev->pg_event != MEI_PG_EVENT_RECEIVED) {
942 		ret = -ETIME;
943 		goto out;
944 	}
945 	/* end PGI entry procedure */
946 
947 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
948 
949 	reg = mei_me_d0i3_set(dev, true);
950 	if (!(reg & H_D0I3C_CIP)) {
951 		dev_dbg(dev->dev, "d0i3 enter wait not needed\n");
952 		ret = 0;
953 		goto on;
954 	}
955 
956 	mutex_unlock(&dev->device_lock);
957 	wait_event_timeout(dev->wait_pg,
958 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
959 		dev->timeouts.d0i3);
960 	mutex_lock(&dev->device_lock);
961 
962 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
963 		reg = mei_me_d0i3c_read(dev);
964 		if (!(reg & H_D0I3C_I3)) {
965 			ret = -ETIME;
966 			goto out;
967 		}
968 	}
969 
970 	ret = 0;
971 on:
972 	hw->pg_state = MEI_PG_ON;
973 out:
974 	dev->pg_event = MEI_PG_EVENT_IDLE;
975 	dev_dbg(dev->dev, "d0i3 enter ret = %d\n", ret);
976 	return ret;
977 }
978 
979 /**
980  * mei_me_d0i3_enter - perform d0i3 entry procedure
981  *   no hbm PG handshake
982  *   no waiting for confirmation; runs with interrupts
983  *   disabled
984  *
985  * @dev: the device structure
986  *
987  * Return: 0 on success an error code otherwise
988  */
989 static int mei_me_d0i3_enter(struct mei_device *dev)
990 {
991 	struct mei_me_hw *hw = to_me_hw(dev);
992 	u32 reg;
993 
994 	reg = mei_me_d0i3c_read(dev);
995 	if (reg & H_D0I3C_I3) {
996 		/* we are in d0i3, nothing to do */
997 		dev_dbg(dev->dev, "already d0i3 : set not needed\n");
998 		goto on;
999 	}
1000 
1001 	mei_me_d0i3_set(dev, false);
1002 on:
1003 	hw->pg_state = MEI_PG_ON;
1004 	dev->pg_event = MEI_PG_EVENT_IDLE;
1005 	dev_dbg(dev->dev, "d0i3 enter\n");
1006 	return 0;
1007 }
1008 
1009 /**
1010  * mei_me_d0i3_exit_sync - perform d0i3 exit procedure
1011  *
1012  * @dev: the device structure
1013  *
1014  * Return: 0 on success an error code otherwise
1015  */
1016 static int mei_me_d0i3_exit_sync(struct mei_device *dev)
1017 {
1018 	struct mei_me_hw *hw = to_me_hw(dev);
1019 	int ret;
1020 	u32 reg;
1021 
1022 	dev->pg_event = MEI_PG_EVENT_INTR_WAIT;
1023 
1024 	reg = mei_me_d0i3c_read(dev);
1025 	if (!(reg & H_D0I3C_I3)) {
1026 		/* we are not in d0i3, nothing to do */
1027 		dev_dbg(dev->dev, "d0i3 exit not needed\n");
1028 		ret = 0;
1029 		goto off;
1030 	}
1031 
1032 	reg = mei_me_d0i3_unset(dev);
1033 	if (!(reg & H_D0I3C_CIP)) {
1034 		dev_dbg(dev->dev, "d0i3 exit wait not needed\n");
1035 		ret = 0;
1036 		goto off;
1037 	}
1038 
1039 	mutex_unlock(&dev->device_lock);
1040 	wait_event_timeout(dev->wait_pg,
1041 		dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED,
1042 		dev->timeouts.d0i3);
1043 	mutex_lock(&dev->device_lock);
1044 
1045 	if (dev->pg_event != MEI_PG_EVENT_INTR_RECEIVED) {
1046 		reg = mei_me_d0i3c_read(dev);
1047 		if (reg & H_D0I3C_I3) {
1048 			ret = -ETIME;
1049 			goto out;
1050 		}
1051 	}
1052 
1053 	ret = 0;
1054 off:
1055 	hw->pg_state = MEI_PG_OFF;
1056 out:
1057 	dev->pg_event = MEI_PG_EVENT_IDLE;
1058 
1059 	dev_dbg(dev->dev, "d0i3 exit ret = %d\n", ret);
1060 	return ret;
1061 }
1062 
1063 /**
1064  * mei_me_pg_legacy_intr - perform legacy pg processing
1065  *			   in interrupt thread handler
1066  *
1067  * @dev: the device structure
1068  */
1069 static void mei_me_pg_legacy_intr(struct mei_device *dev)
1070 {
1071 	struct mei_me_hw *hw = to_me_hw(dev);
1072 
1073 	if (dev->pg_event != MEI_PG_EVENT_INTR_WAIT)
1074 		return;
1075 
1076 	dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
1077 	hw->pg_state = MEI_PG_OFF;
1078 	if (waitqueue_active(&dev->wait_pg))
1079 		wake_up(&dev->wait_pg);
1080 }
1081 
1082 /**
1083  * mei_me_d0i3_intr - perform d0i3 processing in interrupt thread handler
1084  *
1085  * @dev: the device structure
1086  * @intr_source: interrupt source
1087  */
1088 static void mei_me_d0i3_intr(struct mei_device *dev, u32 intr_source)
1089 {
1090 	struct mei_me_hw *hw = to_me_hw(dev);
1091 
1092 	if (dev->pg_event == MEI_PG_EVENT_INTR_WAIT &&
1093 	    (intr_source & H_D0I3C_IS)) {
1094 		dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED;
1095 		if (hw->pg_state == MEI_PG_ON) {
1096 			hw->pg_state = MEI_PG_OFF;
1097 			if (dev->hbm_state != MEI_HBM_IDLE) {
1098 				/*
1099 				 * force H_RDY because it could be
1100 				 * wiped off during PG
1101 				 */
1102 				dev_dbg(dev->dev, "d0i3 set host ready\n");
1103 				mei_me_host_set_ready(dev);
1104 			}
1105 		} else {
1106 			hw->pg_state = MEI_PG_ON;
1107 		}
1108 
1109 		wake_up(&dev->wait_pg);
1110 	}
1111 
1112 	if (hw->pg_state == MEI_PG_ON && (intr_source & H_IS)) {
1113 		/*
1114 		 * HW sent some data and we are in D0i3, so
1115 		 * we got here because of HW initiated exit from D0i3.
1116 		 * Start runtime pm resume sequence to exit low power state.
1117 		 */
1118 		dev_dbg(dev->dev, "d0i3 want resume\n");
1119 		mei_hbm_pg_resume(dev);
1120 	}
1121 }
1122 
1123 /**
1124  * mei_me_pg_intr - perform pg processing in interrupt thread handler
1125  *
1126  * @dev: the device structure
1127  * @intr_source: interrupt source
1128  */
1129 static void mei_me_pg_intr(struct mei_device *dev, u32 intr_source)
1130 {
1131 	struct mei_me_hw *hw = to_me_hw(dev);
1132 
1133 	if (hw->d0i3_supported)
1134 		mei_me_d0i3_intr(dev, intr_source);
1135 	else
1136 		mei_me_pg_legacy_intr(dev);
1137 }
1138 
1139 /**
1140  * mei_me_pg_enter_sync - perform runtime pm entry procedure
1141  *
1142  * @dev: the device structure
1143  *
1144  * Return: 0 on success an error code otherwise
1145  */
1146 int mei_me_pg_enter_sync(struct mei_device *dev)
1147 {
1148 	struct mei_me_hw *hw = to_me_hw(dev);
1149 
1150 	if (hw->d0i3_supported)
1151 		return mei_me_d0i3_enter_sync(dev);
1152 	else
1153 		return mei_me_pg_legacy_enter_sync(dev);
1154 }
1155 
1156 /**
1157  * mei_me_pg_exit_sync - perform runtime pm exit procedure
1158  *
1159  * @dev: the device structure
1160  *
1161  * Return: 0 on success an error code otherwise
1162  */
1163 int mei_me_pg_exit_sync(struct mei_device *dev)
1164 {
1165 	struct mei_me_hw *hw = to_me_hw(dev);
1166 
1167 	if (hw->d0i3_supported)
1168 		return mei_me_d0i3_exit_sync(dev);
1169 	else
1170 		return mei_me_pg_legacy_exit_sync(dev);
1171 }
1172 
1173 /**
1174  * mei_me_hw_reset - resets fw via mei csr register.
1175  *
1176  * @dev: the device structure
1177  * @intr_enable: if interrupt should be enabled after reset.
1178  *
1179  * Return: 0 on success an error code otherwise
1180  */
1181 static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
1182 {
1183 	struct mei_me_hw *hw = to_me_hw(dev);
1184 	int ret;
1185 	u32 hcsr;
1186 
1187 	if (intr_enable) {
1188 		mei_me_intr_enable(dev);
1189 		if (hw->d0i3_supported) {
1190 			ret = mei_me_d0i3_exit_sync(dev);
1191 			if (ret)
1192 				return ret;
1193 		} else {
1194 			hw->pg_state = MEI_PG_OFF;
1195 		}
1196 	}
1197 
1198 	pm_runtime_set_active(dev->dev);
1199 
1200 	hcsr = mei_hcsr_read(dev);
1201 	/* H_RST may be found lit before reset is started,
1202 	 * for example if preceding reset flow hasn't completed.
1203 	 * In that case asserting H_RST will be ignored, therefore
1204 	 * we need to clean H_RST bit to start a successful reset sequence.
1205 	 */
1206 	if ((hcsr & H_RST) == H_RST) {
1207 		dev_warn(dev->dev, "H_RST is set = 0x%08X", hcsr);
1208 		hcsr &= ~H_RST;
1209 		mei_hcsr_set(dev, hcsr);
1210 		hcsr = mei_hcsr_read(dev);
1211 	}
1212 
1213 	hcsr |= H_RST | H_IG | H_CSR_IS_MASK;
1214 
1215 	if (!intr_enable || mei_me_hw_use_polling(to_me_hw(dev)))
1216 		hcsr &= ~H_CSR_IE_MASK;
1217 
1218 	dev->recvd_hw_ready = false;
1219 	mei_hcsr_write(dev, hcsr);
1220 
1221 	/*
1222 	 * Host reads the H_CSR once to ensure that the
1223 	 * posted write to H_CSR completes.
1224 	 */
1225 	hcsr = mei_hcsr_read(dev);
1226 
1227 	if ((hcsr & H_RST) == 0)
1228 		dev_warn(dev->dev, "H_RST is not set = 0x%08X", hcsr);
1229 
1230 	if ((hcsr & H_RDY) == H_RDY)
1231 		dev_warn(dev->dev, "H_RDY is not cleared 0x%08X", hcsr);
1232 
1233 	if (!intr_enable) {
1234 		mei_me_hw_reset_release(dev);
1235 		if (hw->d0i3_supported) {
1236 			ret = mei_me_d0i3_enter(dev);
1237 			if (ret)
1238 				return ret;
1239 		}
1240 	}
1241 	return 0;
1242 }
1243 
1244 /**
1245  * mei_me_irq_quick_handler - The ISR of the MEI device
1246  *
1247  * @irq: The irq number
1248  * @dev_id: pointer to the device structure
1249  *
1250  * Return: irqreturn_t
1251  */
1252 irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
1253 {
1254 	struct mei_device *dev = (struct mei_device *)dev_id;
1255 	u32 hcsr;
1256 
1257 	hcsr = mei_hcsr_read(dev);
1258 	if (!me_intr_src(hcsr))
1259 		return IRQ_NONE;
1260 
1261 	dev_dbg(dev->dev, "interrupt source 0x%08X\n", me_intr_src(hcsr));
1262 
1263 	/* disable interrupts on device */
1264 	me_intr_disable(dev, hcsr);
1265 	return IRQ_WAKE_THREAD;
1266 }
1267 EXPORT_SYMBOL_GPL(mei_me_irq_quick_handler);
1268 
1269 /**
1270  * mei_me_irq_thread_handler - function called after ISR to handle the interrupt
1271  * processing.
1272  *
1273  * @irq: The irq number
1274  * @dev_id: pointer to the device structure
1275  *
1276  * Return: irqreturn_t
1277  *
1278  */
1279 irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
1280 {
1281 	struct mei_device *dev = (struct mei_device *) dev_id;
1282 	struct list_head cmpl_list;
1283 	s32 slots;
1284 	u32 hcsr;
1285 	int rets = 0;
1286 
1287 	dev_dbg(dev->dev, "function called after ISR to handle the interrupt processing.\n");
1288 	/* initialize our complete list */
1289 	mutex_lock(&dev->device_lock);
1290 
1291 	hcsr = mei_hcsr_read(dev);
1292 	me_intr_clear(dev, hcsr);
1293 
1294 	INIT_LIST_HEAD(&cmpl_list);
1295 
1296 	/* check if ME wants a reset */
1297 	if (!mei_hw_is_ready(dev) && dev->dev_state != MEI_DEV_RESETTING) {
1298 		dev_warn(dev->dev, "FW not ready: resetting: dev_state = %d pxp = %d\n",
1299 			 dev->dev_state, dev->pxp_mode);
1300 		if (dev->dev_state == MEI_DEV_POWERING_DOWN ||
1301 		    dev->dev_state == MEI_DEV_POWER_DOWN)
1302 			mei_cl_all_disconnect(dev);
1303 		else if (dev->dev_state != MEI_DEV_DISABLED)
1304 			schedule_work(&dev->reset_work);
1305 		goto end;
1306 	}
1307 
1308 	if (mei_me_hw_is_resetting(dev))
1309 		mei_hcsr_set_hig(dev);
1310 
1311 	mei_me_pg_intr(dev, me_intr_src(hcsr));
1312 
1313 	/*  check if we need to start the dev */
1314 	if (!mei_host_is_ready(dev)) {
1315 		if (mei_hw_is_ready(dev)) {
1316 			dev_dbg(dev->dev, "we need to start the dev.\n");
1317 			dev->recvd_hw_ready = true;
1318 			wake_up(&dev->wait_hw_ready);
1319 		} else {
1320 			dev_dbg(dev->dev, "Spurious Interrupt\n");
1321 		}
1322 		goto end;
1323 	}
1324 	/* check slots available for reading */
1325 	slots = mei_count_full_read_slots(dev);
1326 	while (slots > 0) {
1327 		dev_dbg(dev->dev, "slots to read = %08x\n", slots);
1328 		rets = mei_irq_read_handler(dev, &cmpl_list, &slots);
1329 		/* There is a race between ME write and interrupt delivery:
1330 		 * Not all data is always available immediately after the
1331 		 * interrupt, so try to read again on the next interrupt.
1332 		 */
1333 		if (rets == -ENODATA)
1334 			break;
1335 
1336 		if (rets) {
1337 			dev_err(dev->dev, "mei_irq_read_handler ret = %d, state = %d.\n",
1338 				rets, dev->dev_state);
1339 			if (dev->dev_state != MEI_DEV_RESETTING &&
1340 			    dev->dev_state != MEI_DEV_DISABLED &&
1341 			    dev->dev_state != MEI_DEV_POWERING_DOWN &&
1342 			    dev->dev_state != MEI_DEV_POWER_DOWN)
1343 				schedule_work(&dev->reset_work);
1344 			goto end;
1345 		}
1346 	}
1347 
1348 	dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1349 
1350 	/*
1351 	 * During PG handshake only allowed write is the replay to the
1352 	 * PG exit message, so block calling write function
1353 	 * if the pg event is in PG handshake
1354 	 */
1355 	if (dev->pg_event != MEI_PG_EVENT_WAIT &&
1356 	    dev->pg_event != MEI_PG_EVENT_RECEIVED) {
1357 		rets = mei_irq_write_handler(dev, &cmpl_list);
1358 		dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
1359 	}
1360 
1361 	mei_irq_compl_handler(dev, &cmpl_list);
1362 
1363 end:
1364 	dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets);
1365 	mei_me_intr_enable(dev);
1366 	mutex_unlock(&dev->device_lock);
1367 	return IRQ_HANDLED;
1368 }
1369 EXPORT_SYMBOL_GPL(mei_me_irq_thread_handler);
1370 
1371 #define MEI_POLLING_TIMEOUT_ACTIVE 100
1372 #define MEI_POLLING_TIMEOUT_IDLE   500
1373 
1374 /**
1375  * mei_me_polling_thread - interrupt register polling thread
1376  *
1377  * The thread monitors the interrupt source register and calls
1378  * mei_me_irq_thread_handler() to handle the firmware
1379  * input.
1380  *
1381  * The function polls in MEI_POLLING_TIMEOUT_ACTIVE timeout
1382  * in case there was an event, in idle case the polling
1383  * time increases yet again by MEI_POLLING_TIMEOUT_ACTIVE
1384  * up to MEI_POLLING_TIMEOUT_IDLE.
1385  *
1386  * @_dev: mei device
1387  *
1388  * Return: always 0
1389  */
1390 int mei_me_polling_thread(void *_dev)
1391 {
1392 	struct mei_device *dev = _dev;
1393 	irqreturn_t irq_ret;
1394 	long polling_timeout = MEI_POLLING_TIMEOUT_ACTIVE;
1395 
1396 	dev_dbg(dev->dev, "kernel thread is running\n");
1397 	while (!kthread_should_stop()) {
1398 		struct mei_me_hw *hw = to_me_hw(dev);
1399 		u32 hcsr;
1400 
1401 		wait_event_timeout(hw->wait_active,
1402 				   hw->is_active || kthread_should_stop(),
1403 				   msecs_to_jiffies(MEI_POLLING_TIMEOUT_IDLE));
1404 
1405 		if (kthread_should_stop())
1406 			break;
1407 
1408 		hcsr = mei_hcsr_read(dev);
1409 		if (me_intr_src(hcsr)) {
1410 			polling_timeout = MEI_POLLING_TIMEOUT_ACTIVE;
1411 			irq_ret = mei_me_irq_thread_handler(1, dev);
1412 			if (irq_ret != IRQ_HANDLED)
1413 				dev_err(dev->dev, "irq_ret %d\n", irq_ret);
1414 		} else {
1415 			/*
1416 			 * Increase timeout by MEI_POLLING_TIMEOUT_ACTIVE
1417 			 * up to MEI_POLLING_TIMEOUT_IDLE
1418 			 */
1419 			polling_timeout = clamp_val(polling_timeout + MEI_POLLING_TIMEOUT_ACTIVE,
1420 						    MEI_POLLING_TIMEOUT_ACTIVE,
1421 						    MEI_POLLING_TIMEOUT_IDLE);
1422 		}
1423 
1424 		schedule_timeout_interruptible(msecs_to_jiffies(polling_timeout));
1425 	}
1426 
1427 	return 0;
1428 }
1429 EXPORT_SYMBOL_GPL(mei_me_polling_thread);
1430 
1431 static const struct mei_hw_ops mei_me_hw_ops = {
1432 
1433 	.trc_status = mei_me_trc_status,
1434 	.fw_status = mei_me_fw_status,
1435 	.pg_state  = mei_me_pg_state,
1436 
1437 	.host_is_ready = mei_me_host_is_ready,
1438 
1439 	.hw_is_ready = mei_me_hw_is_ready,
1440 	.hw_reset = mei_me_hw_reset,
1441 	.hw_config = mei_me_hw_config,
1442 	.hw_start = mei_me_hw_start,
1443 
1444 	.pg_in_transition = mei_me_pg_in_transition,
1445 	.pg_is_enabled = mei_me_pg_is_enabled,
1446 
1447 	.intr_clear = mei_me_intr_clear,
1448 	.intr_enable = mei_me_intr_enable,
1449 	.intr_disable = mei_me_intr_disable,
1450 	.synchronize_irq = mei_me_synchronize_irq,
1451 
1452 	.hbuf_free_slots = mei_me_hbuf_empty_slots,
1453 	.hbuf_is_ready = mei_me_hbuf_is_empty,
1454 	.hbuf_depth = mei_me_hbuf_depth,
1455 
1456 	.write = mei_me_hbuf_write,
1457 
1458 	.rdbuf_full_slots = mei_me_count_full_read_slots,
1459 	.read_hdr = mei_me_mecbrw_read,
1460 	.read = mei_me_read_slots
1461 };
1462 
1463 /**
1464  * mei_me_fw_type_nm() - check for nm sku
1465  *
1466  * Read ME FW Status register to check for the Node Manager (NM) Firmware.
1467  * The NM FW is only signaled in PCI function 0.
1468  * __Note__: Deprecated by PCH8 and newer.
1469  *
1470  * @pdev: pci device
1471  *
1472  * Return: true in case of NM firmware
1473  */
1474 static bool mei_me_fw_type_nm(const struct pci_dev *pdev)
1475 {
1476 	u32 reg;
1477 	unsigned int devfn;
1478 
1479 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1480 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_2, &reg);
1481 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_2", PCI_CFG_HFS_2, reg);
1482 	/* make sure that bit 9 (NM) is up and bit 10 (DM) is down */
1483 	return (reg & 0x600) == 0x200;
1484 }
1485 
1486 #define MEI_CFG_FW_NM                           \
1487 	.quirk_probe = mei_me_fw_type_nm
1488 
1489 /**
1490  * mei_me_fw_type_sps_4() - check for sps 4.0 sku
1491  *
1492  * Read ME FW Status register to check for SPS Firmware.
1493  * The SPS FW is only signaled in the PCI function 0.
1494  * __Note__: Deprecated by SPS 5.0 and newer.
1495  *
1496  * @pdev: pci device
1497  *
1498  * Return: true in case of SPS firmware
1499  */
1500 static bool mei_me_fw_type_sps_4(const struct pci_dev *pdev)
1501 {
1502 	u32 reg;
1503 	unsigned int devfn;
1504 
1505 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1506 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_1, &reg);
1507 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_1", PCI_CFG_HFS_1, reg);
1508 	return (reg & PCI_CFG_HFS_1_OPMODE_MSK) == PCI_CFG_HFS_1_OPMODE_SPS;
1509 }
1510 
1511 #define MEI_CFG_FW_SPS_4                          \
1512 	.quirk_probe = mei_me_fw_type_sps_4
1513 
1514 /**
1515  * mei_me_fw_type_sps_ign() - check for sps or ign sku
1516  *
1517  * Read ME FW Status register to check for SPS or IGN Firmware.
1518  * The SPS/IGN FW is only signaled in pci function 0
1519  *
1520  * @pdev: pci device
1521  *
1522  * Return: true in case of SPS/IGN firmware
1523  */
1524 static bool mei_me_fw_type_sps_ign(const struct pci_dev *pdev)
1525 {
1526 	u32 reg;
1527 	u32 fw_type;
1528 	unsigned int devfn;
1529 
1530 	devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
1531 	pci_bus_read_config_dword(pdev->bus, devfn, PCI_CFG_HFS_3, &reg);
1532 	trace_mei_pci_cfg_read(&pdev->dev, "PCI_CFG_HFS_3", PCI_CFG_HFS_3, reg);
1533 	fw_type = (reg & PCI_CFG_HFS_3_FW_SKU_MSK);
1534 
1535 	dev_dbg(&pdev->dev, "fw type is %d\n", fw_type);
1536 
1537 	return fw_type == PCI_CFG_HFS_3_FW_SKU_IGN ||
1538 	       fw_type == PCI_CFG_HFS_3_FW_SKU_SPS;
1539 }
1540 
1541 #define MEI_CFG_KIND_ITOUCH                     \
1542 	.kind = "itouch"
1543 
1544 #define MEI_CFG_TYPE_GSC                        \
1545 	.kind = "gsc"
1546 
1547 #define MEI_CFG_TYPE_GSCFI                      \
1548 	.kind = "gscfi"
1549 
1550 #define MEI_CFG_FW_SPS_IGN                      \
1551 	.quirk_probe = mei_me_fw_type_sps_ign
1552 
1553 #define MEI_CFG_FW_VER_SUPP                     \
1554 	.fw_ver_supported = 1
1555 
1556 #define MEI_CFG_ICH_HFS                      \
1557 	.fw_status.count = 0
1558 
1559 #define MEI_CFG_ICH10_HFS                        \
1560 	.fw_status.count = 1,                   \
1561 	.fw_status.status[0] = PCI_CFG_HFS_1
1562 
1563 #define MEI_CFG_PCH_HFS                         \
1564 	.fw_status.count = 2,                   \
1565 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1566 	.fw_status.status[1] = PCI_CFG_HFS_2
1567 
1568 #define MEI_CFG_PCH8_HFS                        \
1569 	.fw_status.count = 6,                   \
1570 	.fw_status.status[0] = PCI_CFG_HFS_1,   \
1571 	.fw_status.status[1] = PCI_CFG_HFS_2,   \
1572 	.fw_status.status[2] = PCI_CFG_HFS_3,   \
1573 	.fw_status.status[3] = PCI_CFG_HFS_4,   \
1574 	.fw_status.status[4] = PCI_CFG_HFS_5,   \
1575 	.fw_status.status[5] = PCI_CFG_HFS_6
1576 
1577 #define MEI_CFG_DMA_128 \
1578 	.dma_size[DMA_DSCR_HOST] = SZ_128K, \
1579 	.dma_size[DMA_DSCR_DEVICE] = SZ_128K, \
1580 	.dma_size[DMA_DSCR_CTRL] = PAGE_SIZE
1581 
1582 #define MEI_CFG_TRC \
1583 	.hw_trc_supported = 1
1584 
1585 /* ICH Legacy devices */
1586 static const struct mei_cfg mei_me_ich_cfg = {
1587 	MEI_CFG_ICH_HFS,
1588 };
1589 
1590 /* ICH devices */
1591 static const struct mei_cfg mei_me_ich10_cfg = {
1592 	MEI_CFG_ICH10_HFS,
1593 };
1594 
1595 /* PCH6 devices */
1596 static const struct mei_cfg mei_me_pch6_cfg = {
1597 	MEI_CFG_PCH_HFS,
1598 };
1599 
1600 /* PCH7 devices */
1601 static const struct mei_cfg mei_me_pch7_cfg = {
1602 	MEI_CFG_PCH_HFS,
1603 	MEI_CFG_FW_VER_SUPP,
1604 };
1605 
1606 /* PCH Cougar Point and Patsburg with quirk for Node Manager exclusion */
1607 static const struct mei_cfg mei_me_pch_cpt_pbg_cfg = {
1608 	MEI_CFG_PCH_HFS,
1609 	MEI_CFG_FW_VER_SUPP,
1610 	MEI_CFG_FW_NM,
1611 };
1612 
1613 /* PCH8 Lynx Point and newer devices */
1614 static const struct mei_cfg mei_me_pch8_cfg = {
1615 	MEI_CFG_PCH8_HFS,
1616 	MEI_CFG_FW_VER_SUPP,
1617 };
1618 
1619 /* PCH8 Lynx Point and newer devices - iTouch */
1620 static const struct mei_cfg mei_me_pch8_itouch_cfg = {
1621 	MEI_CFG_KIND_ITOUCH,
1622 	MEI_CFG_PCH8_HFS,
1623 	MEI_CFG_FW_VER_SUPP,
1624 };
1625 
1626 /* PCH8 Lynx Point with quirk for SPS Firmware exclusion */
1627 static const struct mei_cfg mei_me_pch8_sps_4_cfg = {
1628 	MEI_CFG_PCH8_HFS,
1629 	MEI_CFG_FW_VER_SUPP,
1630 	MEI_CFG_FW_SPS_4,
1631 };
1632 
1633 /* LBG with quirk for SPS (4.0) Firmware exclusion */
1634 static const struct mei_cfg mei_me_pch12_sps_4_cfg = {
1635 	MEI_CFG_PCH8_HFS,
1636 	MEI_CFG_FW_VER_SUPP,
1637 	MEI_CFG_FW_SPS_4,
1638 };
1639 
1640 /* Cannon Lake and newer devices */
1641 static const struct mei_cfg mei_me_pch12_cfg = {
1642 	MEI_CFG_PCH8_HFS,
1643 	MEI_CFG_FW_VER_SUPP,
1644 	MEI_CFG_DMA_128,
1645 };
1646 
1647 /* Cannon Lake with quirk for SPS 5.0 and newer Firmware exclusion */
1648 static const struct mei_cfg mei_me_pch12_sps_cfg = {
1649 	MEI_CFG_PCH8_HFS,
1650 	MEI_CFG_FW_VER_SUPP,
1651 	MEI_CFG_DMA_128,
1652 	MEI_CFG_FW_SPS_IGN,
1653 };
1654 
1655 /* Cannon Lake itouch with quirk for SPS 5.0 and newer Firmware exclusion
1656  * w/o DMA support.
1657  */
1658 static const struct mei_cfg mei_me_pch12_itouch_sps_cfg = {
1659 	MEI_CFG_KIND_ITOUCH,
1660 	MEI_CFG_PCH8_HFS,
1661 	MEI_CFG_FW_VER_SUPP,
1662 	MEI_CFG_FW_SPS_IGN,
1663 };
1664 
1665 /* Tiger Lake and newer devices */
1666 static const struct mei_cfg mei_me_pch15_cfg = {
1667 	MEI_CFG_PCH8_HFS,
1668 	MEI_CFG_FW_VER_SUPP,
1669 	MEI_CFG_DMA_128,
1670 	MEI_CFG_TRC,
1671 };
1672 
1673 /* Tiger Lake with quirk for SPS 5.0 and newer Firmware exclusion */
1674 static const struct mei_cfg mei_me_pch15_sps_cfg = {
1675 	MEI_CFG_PCH8_HFS,
1676 	MEI_CFG_FW_VER_SUPP,
1677 	MEI_CFG_DMA_128,
1678 	MEI_CFG_TRC,
1679 	MEI_CFG_FW_SPS_IGN,
1680 };
1681 
1682 /* Graphics System Controller */
1683 static const struct mei_cfg mei_me_gsc_cfg = {
1684 	MEI_CFG_TYPE_GSC,
1685 	MEI_CFG_PCH8_HFS,
1686 	MEI_CFG_FW_VER_SUPP,
1687 };
1688 
1689 /* Graphics System Controller Firmware Interface */
1690 static const struct mei_cfg mei_me_gscfi_cfg = {
1691 	MEI_CFG_TYPE_GSCFI,
1692 	MEI_CFG_PCH8_HFS,
1693 	MEI_CFG_FW_VER_SUPP,
1694 };
1695 
1696 /*
1697  * mei_cfg_list - A list of platform platform specific configurations.
1698  * Note: has to be synchronized with  enum mei_cfg_idx.
1699  */
1700 static const struct mei_cfg *const mei_cfg_list[] = {
1701 	[MEI_ME_UNDEF_CFG] = NULL,
1702 	[MEI_ME_ICH_CFG] = &mei_me_ich_cfg,
1703 	[MEI_ME_ICH10_CFG] = &mei_me_ich10_cfg,
1704 	[MEI_ME_PCH6_CFG] = &mei_me_pch6_cfg,
1705 	[MEI_ME_PCH7_CFG] = &mei_me_pch7_cfg,
1706 	[MEI_ME_PCH_CPT_PBG_CFG] = &mei_me_pch_cpt_pbg_cfg,
1707 	[MEI_ME_PCH8_CFG] = &mei_me_pch8_cfg,
1708 	[MEI_ME_PCH8_ITOUCH_CFG] = &mei_me_pch8_itouch_cfg,
1709 	[MEI_ME_PCH8_SPS_4_CFG] = &mei_me_pch8_sps_4_cfg,
1710 	[MEI_ME_PCH12_CFG] = &mei_me_pch12_cfg,
1711 	[MEI_ME_PCH12_SPS_4_CFG] = &mei_me_pch12_sps_4_cfg,
1712 	[MEI_ME_PCH12_SPS_CFG] = &mei_me_pch12_sps_cfg,
1713 	[MEI_ME_PCH12_SPS_ITOUCH_CFG] = &mei_me_pch12_itouch_sps_cfg,
1714 	[MEI_ME_PCH15_CFG] = &mei_me_pch15_cfg,
1715 	[MEI_ME_PCH15_SPS_CFG] = &mei_me_pch15_sps_cfg,
1716 	[MEI_ME_GSC_CFG] = &mei_me_gsc_cfg,
1717 	[MEI_ME_GSCFI_CFG] = &mei_me_gscfi_cfg,
1718 };
1719 
1720 const struct mei_cfg *mei_me_get_cfg(kernel_ulong_t idx)
1721 {
1722 	BUILD_BUG_ON(ARRAY_SIZE(mei_cfg_list) != MEI_ME_NUM_CFG);
1723 
1724 	if (idx >= MEI_ME_NUM_CFG)
1725 		return NULL;
1726 
1727 	return mei_cfg_list[idx];
1728 }
1729 EXPORT_SYMBOL_GPL(mei_me_get_cfg);
1730 
1731 /**
1732  * mei_me_dev_init - allocates and initializes the mei device structure
1733  *
1734  * @parent: device associated with physical device (pci/platform)
1735  * @cfg: per device generation config
1736  * @slow_fw: configure longer timeouts as FW is slow
1737  *
1738  * Return: The mei_device pointer on success, NULL on failure.
1739  */
1740 struct mei_device *mei_me_dev_init(struct device *parent,
1741 				   const struct mei_cfg *cfg, bool slow_fw)
1742 {
1743 	struct mei_device *dev;
1744 	struct mei_me_hw *hw;
1745 	int i;
1746 
1747 	dev = devm_kzalloc(parent, sizeof(*dev) + sizeof(*hw), GFP_KERNEL);
1748 	if (!dev)
1749 		return NULL;
1750 
1751 	hw = to_me_hw(dev);
1752 
1753 	for (i = 0; i < DMA_DSCR_NUM; i++)
1754 		dev->dr_dscr[i].size = cfg->dma_size[i];
1755 
1756 	mei_device_init(dev, parent, slow_fw, &mei_me_hw_ops);
1757 	hw->cfg = cfg;
1758 
1759 	dev->fw_f_fw_ver_supported = cfg->fw_ver_supported;
1760 
1761 	dev->kind = cfg->kind;
1762 
1763 	return dev;
1764 }
1765 EXPORT_SYMBOL_GPL(mei_me_dev_init);
1766