1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * H/W layer of ISHTP provider device (ISH)
4 *
5 * Copyright (c) 2014-2016, Intel Corporation.
6 */
7
8#include <linux/devm-helpers.h>
9#include <linux/sched.h>
10#include <linux/spinlock.h>
11#include <linux/delay.h>
12#include <linux/jiffies.h>
13#include "client.h"
14#include "hw-ish.h"
15#include "hbm.h"
16
17/* For FW reset flow */
18static struct work_struct fw_reset_work;
19static struct ishtp_device *ishtp_dev;
20
21/**
22 * ish_reg_read() - Read register
23 * @dev: ISHTP device pointer
24 * @offset: Register offset
25 *
26 * Read 32 bit register at a given offset
27 *
28 * Return: Read register value
29 */
30static inline uint32_t ish_reg_read(const struct ishtp_device *dev,
31	unsigned long offset)
32{
33	struct ish_hw *hw = to_ish_hw(dev);
34
35	return readl(hw->mem_addr + offset);
36}
37
38/**
39 * ish_reg_write() - Write register
40 * @dev: ISHTP device pointer
41 * @offset: Register offset
42 * @value: Value to write
43 *
44 * Writes 32 bit register at a give offset
45 */
46static inline void ish_reg_write(struct ishtp_device *dev,
47				 unsigned long offset,
48				 uint32_t value)
49{
50	struct ish_hw *hw = to_ish_hw(dev);
51
52	writel(value, hw->mem_addr + offset);
53}
54
55/**
56 * _ish_read_fw_sts_reg() - Read FW status register
57 * @dev: ISHTP device pointer
58 *
59 * Read FW status register
60 *
61 * Return: Read register value
62 */
63static inline uint32_t _ish_read_fw_sts_reg(struct ishtp_device *dev)
64{
65	return ish_reg_read(dev, IPC_REG_ISH_HOST_FWSTS);
66}
67
68/**
69 * check_generated_interrupt() - Check if ISH interrupt
70 * @dev: ISHTP device pointer
71 *
72 * Check if an interrupt was generated for ISH
73 *
74 * Return: Read true or false
75 */
76static bool check_generated_interrupt(struct ishtp_device *dev)
77{
78	bool interrupt_generated = true;
79	uint32_t pisr_val = 0;
80
81	if (dev->pdev->device == CHV_DEVICE_ID) {
82		pisr_val = ish_reg_read(dev, IPC_REG_PISR_CHV_AB);
83		interrupt_generated =
84			IPC_INT_FROM_ISH_TO_HOST_CHV_AB(pisr_val);
85	} else {
86		pisr_val = ish_reg_read(dev, IPC_REG_PISR_BXT);
87		interrupt_generated = !!pisr_val;
88		/* only busy-clear bit is RW, others are RO */
89		if (pisr_val)
90			ish_reg_write(dev, IPC_REG_PISR_BXT, pisr_val);
91	}
92
93	return interrupt_generated;
94}
95
96/**
97 * ish_is_input_ready() - Check if FW ready for RX
98 * @dev: ISHTP device pointer
99 *
100 * Check if ISH FW is ready for receiving data
101 *
102 * Return: Read true or false
103 */
104static bool ish_is_input_ready(struct ishtp_device *dev)
105{
106	uint32_t doorbell_val;
107
108	doorbell_val = ish_reg_read(dev, IPC_REG_HOST2ISH_DRBL);
109	return !IPC_IS_BUSY(doorbell_val);
110}
111
112/**
113 * set_host_ready() - Indicate host ready
114 * @dev: ISHTP device pointer
115 *
116 * Set host ready indication to FW
117 */
118static void set_host_ready(struct ishtp_device *dev)
119{
120	if (dev->pdev->device == CHV_DEVICE_ID) {
121		if (dev->pdev->revision == REVISION_ID_CHT_A0 ||
122				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
123				REVISION_ID_CHT_Ax_SI)
124			ish_reg_write(dev, IPC_REG_HOST_COMM, 0x81);
125		else if (dev->pdev->revision == REVISION_ID_CHT_B0 ||
126				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
127				REVISION_ID_CHT_Bx_SI ||
128				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
129				REVISION_ID_CHT_Kx_SI ||
130				(dev->pdev->revision & REVISION_ID_SI_MASK) ==
131				REVISION_ID_CHT_Dx_SI) {
132			uint32_t host_comm_val;
133
134			host_comm_val = ish_reg_read(dev, IPC_REG_HOST_COMM);
135			host_comm_val |= IPC_HOSTCOMM_INT_EN_BIT_CHV_AB | 0x81;
136			ish_reg_write(dev, IPC_REG_HOST_COMM, host_comm_val);
137		}
138	} else {
139			uint32_t host_pimr_val;
140
141			host_pimr_val = ish_reg_read(dev, IPC_REG_PIMR_BXT);
142			host_pimr_val |= IPC_PIMR_INT_EN_BIT_BXT;
143			/*
144			 * disable interrupt generated instead of
145			 * RX_complete_msg
146			 */
147			host_pimr_val &= ~IPC_HOST2ISH_BUSYCLEAR_MASK_BIT;
148
149			ish_reg_write(dev, IPC_REG_PIMR_BXT, host_pimr_val);
150	}
151}
152
153/**
154 * ishtp_fw_is_ready() - Check if FW ready
155 * @dev: ISHTP device pointer
156 *
157 * Check if ISH FW is ready
158 *
159 * Return: Read true or false
160 */
161static bool ishtp_fw_is_ready(struct ishtp_device *dev)
162{
163	uint32_t ish_status = _ish_read_fw_sts_reg(dev);
164
165	return IPC_IS_ISH_ILUP(ish_status) &&
166		IPC_IS_ISH_ISHTP_READY(ish_status);
167}
168
169/**
170 * ish_set_host_rdy() - Indicate host ready
171 * @dev: ISHTP device pointer
172 *
173 * Set host ready indication to FW
174 */
175static void ish_set_host_rdy(struct ishtp_device *dev)
176{
177	uint32_t host_status = ish_reg_read(dev, IPC_REG_HOST_COMM);
178
179	IPC_SET_HOST_READY(host_status);
180	ish_reg_write(dev, IPC_REG_HOST_COMM, host_status);
181}
182
183/**
184 * ish_clr_host_rdy() - Indicate host not ready
185 * @dev: ISHTP device pointer
186 *
187 * Send host not ready indication to FW
188 */
189static void ish_clr_host_rdy(struct ishtp_device *dev)
190{
191	uint32_t host_status = ish_reg_read(dev, IPC_REG_HOST_COMM);
192
193	IPC_CLEAR_HOST_READY(host_status);
194	ish_reg_write(dev, IPC_REG_HOST_COMM, host_status);
195}
196
197static bool ish_chk_host_rdy(struct ishtp_device *dev)
198{
199	uint32_t host_status = ish_reg_read(dev, IPC_REG_HOST_COMM);
200
201	return (host_status & IPC_HOSTCOMM_READY_BIT);
202}
203
204/**
205 * ish_set_host_ready() - reconfig ipc host registers
206 * @dev: ishtp device pointer
207 *
208 * Set host to ready state
209 * This API is called in some case:
210 *    fw is still on, but ipc is powered down.
211 *    such as OOB case.
212 *
213 * Return: 0 for success else error fault code
214 */
215void ish_set_host_ready(struct ishtp_device *dev)
216{
217	if (ish_chk_host_rdy(dev))
218		return;
219
220	ish_set_host_rdy(dev);
221	set_host_ready(dev);
222}
223
224/**
225 * _ishtp_read_hdr() - Read message header
226 * @dev: ISHTP device pointer
227 *
228 * Read header of 32bit length
229 *
230 * Return: Read register value
231 */
232static uint32_t _ishtp_read_hdr(const struct ishtp_device *dev)
233{
234	return ish_reg_read(dev, IPC_REG_ISH2HOST_MSG);
235}
236
237/**
238 * _ishtp_read - Read message
239 * @dev: ISHTP device pointer
240 * @buffer: message buffer
241 * @buffer_length: length of message buffer
242 *
243 * Read message from FW
244 *
245 * Return: Always 0
246 */
247static int _ishtp_read(struct ishtp_device *dev, unsigned char *buffer,
248	unsigned long buffer_length)
249{
250	uint32_t	i;
251	uint32_t	*r_buf = (uint32_t *)buffer;
252	uint32_t	msg_offs;
253
254	msg_offs = IPC_REG_ISH2HOST_MSG + sizeof(struct ishtp_msg_hdr);
255	for (i = 0; i < buffer_length; i += sizeof(uint32_t))
256		*r_buf++ = ish_reg_read(dev, msg_offs + i);
257
258	return 0;
259}
260
261/**
262 * write_ipc_from_queue() - try to write ipc msg from Tx queue to device
263 * @dev: ishtp device pointer
264 *
265 * Check if DRBL is cleared. if it is - write the first IPC msg,  then call
266 * the callback function (unless it's NULL)
267 *
268 * Return: 0 for success else failure code
269 */
270static int write_ipc_from_queue(struct ishtp_device *dev)
271{
272	struct wr_msg_ctl_info	*ipc_link;
273	unsigned long	length;
274	unsigned long	rem;
275	unsigned long	flags;
276	uint32_t	doorbell_val;
277	uint32_t	*r_buf;
278	uint32_t	reg_addr;
279	int	i;
280	void	(*ipc_send_compl)(void *);
281	void	*ipc_send_compl_prm;
282
283	if (dev->dev_state == ISHTP_DEV_DISABLED)
284		return -EINVAL;
285
286	spin_lock_irqsave(&dev->wr_processing_spinlock, flags);
287	if (!ish_is_input_ready(dev)) {
288		spin_unlock_irqrestore(&dev->wr_processing_spinlock, flags);
289		return -EBUSY;
290	}
291
292	/*
293	 * if tx send list is empty - return 0;
294	 * may happen, as RX_COMPLETE handler doesn't check list emptiness.
295	 */
296	if (list_empty(&dev->wr_processing_list)) {
297		spin_unlock_irqrestore(&dev->wr_processing_spinlock, flags);
298		return	0;
299	}
300
301	ipc_link = list_first_entry(&dev->wr_processing_list,
302				    struct wr_msg_ctl_info, link);
303	/* first 4 bytes of the data is the doorbell value (IPC header) */
304	length = ipc_link->length - sizeof(uint32_t);
305	doorbell_val = *(uint32_t *)ipc_link->inline_data;
306	r_buf = (uint32_t *)(ipc_link->inline_data + sizeof(uint32_t));
307
308	/* If sending MNG_SYNC_FW_CLOCK, update clock again */
309	if (IPC_HEADER_GET_PROTOCOL(doorbell_val) == IPC_PROTOCOL_MNG &&
310		IPC_HEADER_GET_MNG_CMD(doorbell_val) == MNG_SYNC_FW_CLOCK) {
311		uint64_t usec_system, usec_utc;
312		struct ipc_time_update_msg time_update;
313		struct time_sync_format ts_format;
314
315		usec_system = ktime_to_us(ktime_get_boottime());
316		usec_utc = ktime_to_us(ktime_get_real());
317		ts_format.ts1_source = HOST_SYSTEM_TIME_USEC;
318		ts_format.ts2_source = HOST_UTC_TIME_USEC;
319		ts_format.reserved = 0;
320
321		time_update.primary_host_time = usec_system;
322		time_update.secondary_host_time = usec_utc;
323		time_update.sync_info = ts_format;
324
325		memcpy(r_buf, &time_update,
326		       sizeof(struct ipc_time_update_msg));
327	}
328
329	for (i = 0, reg_addr = IPC_REG_HOST2ISH_MSG; i < length >> 2; i++,
330			reg_addr += 4)
331		ish_reg_write(dev, reg_addr, r_buf[i]);
332
333	rem = length & 0x3;
334	if (rem > 0) {
335		uint32_t reg = 0;
336
337		memcpy(&reg, &r_buf[length >> 2], rem);
338		ish_reg_write(dev, reg_addr, reg);
339	}
340	ish_reg_write(dev, IPC_REG_HOST2ISH_DRBL, doorbell_val);
341
342	/* Flush writes to msg registers and doorbell */
343	ish_reg_read(dev, IPC_REG_ISH_HOST_FWSTS);
344
345	/* Update IPC counters */
346	++dev->ipc_tx_cnt;
347	dev->ipc_tx_bytes_cnt += IPC_HEADER_GET_LENGTH(doorbell_val);
348
349	ipc_send_compl = ipc_link->ipc_send_compl;
350	ipc_send_compl_prm = ipc_link->ipc_send_compl_prm;
351	list_del_init(&ipc_link->link);
352	list_add(&ipc_link->link, &dev->wr_free_list);
353	spin_unlock_irqrestore(&dev->wr_processing_spinlock, flags);
354
355	/*
356	 * callback will be called out of spinlock,
357	 * after ipc_link returned to free list
358	 */
359	if (ipc_send_compl)
360		ipc_send_compl(ipc_send_compl_prm);
361
362	return 0;
363}
364
365/**
366 * write_ipc_to_queue() - write ipc msg to Tx queue
367 * @dev: ishtp device instance
368 * @ipc_send_compl: Send complete callback
369 * @ipc_send_compl_prm:	Parameter to send in complete callback
370 * @msg: Pointer to message
371 * @length: Length of message
372 *
373 * Recived msg with IPC (and upper protocol) header  and add it to the device
374 *  Tx-to-write list then try to send the first IPC waiting msg
375 *  (if DRBL is cleared)
376 * This function returns negative value for failure (means free list
377 *  is empty, or msg too long) and 0 for success.
378 *
379 * Return: 0 for success else failure code
380 */
381static int write_ipc_to_queue(struct ishtp_device *dev,
382	void (*ipc_send_compl)(void *), void *ipc_send_compl_prm,
383	unsigned char *msg, int length)
384{
385	struct wr_msg_ctl_info *ipc_link;
386	unsigned long flags;
387
388	if (length > IPC_FULL_MSG_SIZE)
389		return -EMSGSIZE;
390
391	spin_lock_irqsave(&dev->wr_processing_spinlock, flags);
392	if (list_empty(&dev->wr_free_list)) {
393		spin_unlock_irqrestore(&dev->wr_processing_spinlock, flags);
394		return -ENOMEM;
395	}
396	ipc_link = list_first_entry(&dev->wr_free_list,
397				    struct wr_msg_ctl_info, link);
398	list_del_init(&ipc_link->link);
399
400	ipc_link->ipc_send_compl = ipc_send_compl;
401	ipc_link->ipc_send_compl_prm = ipc_send_compl_prm;
402	ipc_link->length = length;
403	memcpy(ipc_link->inline_data, msg, length);
404
405	list_add_tail(&ipc_link->link, &dev->wr_processing_list);
406	spin_unlock_irqrestore(&dev->wr_processing_spinlock, flags);
407
408	write_ipc_from_queue(dev);
409
410	return 0;
411}
412
413/**
414 * ipc_send_mng_msg() - Send management message
415 * @dev: ishtp device instance
416 * @msg_code: Message code
417 * @msg: Pointer to message
418 * @size: Length of message
419 *
420 * Send management message to FW
421 *
422 * Return: 0 for success else failure code
423 */
424static int ipc_send_mng_msg(struct ishtp_device *dev, uint32_t msg_code,
425	void *msg, size_t size)
426{
427	unsigned char	ipc_msg[IPC_FULL_MSG_SIZE];
428	uint32_t	drbl_val = IPC_BUILD_MNG_MSG(msg_code, size);
429
430	memcpy(ipc_msg, &drbl_val, sizeof(uint32_t));
431	memcpy(ipc_msg + sizeof(uint32_t), msg, size);
432	return	write_ipc_to_queue(dev, NULL, NULL, ipc_msg,
433		sizeof(uint32_t) + size);
434}
435
436#define WAIT_FOR_FW_RDY			0x1
437#define WAIT_FOR_INPUT_RDY		0x2
438
439/**
440 * timed_wait_for_timeout() - wait special event with timeout
441 * @dev: ISHTP device pointer
442 * @condition: indicate the condition for waiting
443 * @timeinc: time slice for every wait cycle, in ms
444 * @timeout: time in ms for timeout
445 *
446 * This function will check special event to be ready in a loop, the loop
447 * period is specificd in timeinc. Wait timeout will causes failure.
448 *
449 * Return: 0 for success else failure code
450 */
451static int timed_wait_for_timeout(struct ishtp_device *dev, int condition,
452				unsigned int timeinc, unsigned int timeout)
453{
454	bool complete = false;
455	int ret;
456
457	do {
458		if (condition == WAIT_FOR_FW_RDY) {
459			complete = ishtp_fw_is_ready(dev);
460		} else if (condition == WAIT_FOR_INPUT_RDY) {
461			complete = ish_is_input_ready(dev);
462		} else {
463			ret = -EINVAL;
464			goto out;
465		}
466
467		if (!complete) {
468			unsigned long left_time;
469
470			left_time = msleep_interruptible(timeinc);
471			timeout -= (timeinc - left_time);
472		}
473	} while (!complete && timeout > 0);
474
475	if (complete)
476		ret = 0;
477	else
478		ret = -EBUSY;
479
480out:
481	return ret;
482}
483
484#define TIME_SLICE_FOR_FW_RDY_MS		100
485#define TIME_SLICE_FOR_INPUT_RDY_MS		100
486#define TIMEOUT_FOR_FW_RDY_MS			2000
487#define TIMEOUT_FOR_INPUT_RDY_MS		2000
488
489/**
490 * ish_fw_reset_handler() - FW reset handler
491 * @dev: ishtp device pointer
492 *
493 * Handle FW reset
494 *
495 * Return: 0 for success else failure code
496 */
497static int ish_fw_reset_handler(struct ishtp_device *dev)
498{
499	uint32_t	reset_id;
500	unsigned long	flags;
501
502	/* Read reset ID */
503	reset_id = ish_reg_read(dev, IPC_REG_ISH2HOST_MSG) & 0xFFFF;
504
505	/* Clear IPC output queue */
506	spin_lock_irqsave(&dev->wr_processing_spinlock, flags);
507	list_splice_init(&dev->wr_processing_list, &dev->wr_free_list);
508	spin_unlock_irqrestore(&dev->wr_processing_spinlock, flags);
509
510	/* ISHTP notification in IPC_RESET */
511	ishtp_reset_handler(dev);
512
513	if (!ish_is_input_ready(dev))
514		timed_wait_for_timeout(dev, WAIT_FOR_INPUT_RDY,
515			TIME_SLICE_FOR_INPUT_RDY_MS, TIMEOUT_FOR_INPUT_RDY_MS);
516
517	/* ISH FW is dead */
518	if (!ish_is_input_ready(dev))
519		return	-EPIPE;
520	/*
521	 * Set HOST2ISH.ILUP. Apparently we need this BEFORE sending
522	 * RESET_NOTIFY_ACK - FW will be checking for it
523	 */
524	ish_set_host_rdy(dev);
525	/* Send RESET_NOTIFY_ACK (with reset_id) */
526	ipc_send_mng_msg(dev, MNG_RESET_NOTIFY_ACK, &reset_id,
527			 sizeof(uint32_t));
528
529	/* Wait for ISH FW'es ILUP and ISHTP_READY */
530	timed_wait_for_timeout(dev, WAIT_FOR_FW_RDY,
531			TIME_SLICE_FOR_FW_RDY_MS, TIMEOUT_FOR_FW_RDY_MS);
532	if (!ishtp_fw_is_ready(dev)) {
533		/* ISH FW is dead */
534		uint32_t	ish_status;
535
536		ish_status = _ish_read_fw_sts_reg(dev);
537		dev_err(dev->devc,
538			"[ishtp-ish]: completed reset, ISH is dead (FWSTS = %08X)\n",
539			ish_status);
540		return -ENODEV;
541	}
542	return	0;
543}
544
545#define TIMEOUT_FOR_HW_RDY_MS			300
546
547/**
548 * fw_reset_work_fn() - FW reset worker function
549 * @unused: not used
550 *
551 * Call ish_fw_reset_handler to complete FW reset
552 */
553static void fw_reset_work_fn(struct work_struct *unused)
554{
555	int	rv;
556
557	rv = ish_fw_reset_handler(ishtp_dev);
558	if (!rv) {
559		/* ISH is ILUP & ISHTP-ready. Restart ISHTP */
560		msleep_interruptible(TIMEOUT_FOR_HW_RDY_MS);
561		ishtp_dev->recvd_hw_ready = 1;
562		wake_up_interruptible(&ishtp_dev->wait_hw_ready);
563
564		/* ISHTP notification in IPC_RESET sequence completion */
565		ishtp_reset_compl_handler(ishtp_dev);
566	} else
567		dev_err(ishtp_dev->devc, "[ishtp-ish]: FW reset failed (%d)\n",
568			rv);
569}
570
571/**
572 * _ish_sync_fw_clock() -Sync FW clock with the OS clock
573 * @dev: ishtp device pointer
574 *
575 * Sync FW and OS time
576 */
577static void _ish_sync_fw_clock(struct ishtp_device *dev)
578{
579	static unsigned long	prev_sync;
580	uint64_t	usec;
581
582	if (prev_sync && time_before(jiffies, prev_sync + 20 * HZ))
583		return;
584
585	prev_sync = jiffies;
586	usec = ktime_to_us(ktime_get_boottime());
587	ipc_send_mng_msg(dev, MNG_SYNC_FW_CLOCK, &usec, sizeof(uint64_t));
588}
589
590/**
591 * recv_ipc() - Receive and process IPC management messages
592 * @dev: ishtp device instance
593 * @doorbell_val: doorbell value
594 *
595 * This function runs in ISR context.
596 * NOTE: Any other mng command than reset_notify and reset_notify_ack
597 * won't wake BH handler
598 */
599static void	recv_ipc(struct ishtp_device *dev, uint32_t doorbell_val)
600{
601	uint32_t	mng_cmd;
602
603	mng_cmd = IPC_HEADER_GET_MNG_CMD(doorbell_val);
604
605	switch (mng_cmd) {
606	default:
607		break;
608
609	case MNG_RX_CMPL_INDICATION:
610		if (dev->suspend_flag) {
611			dev->suspend_flag = 0;
612			wake_up_interruptible(&dev->suspend_wait);
613		}
614		if (dev->resume_flag) {
615			dev->resume_flag = 0;
616			wake_up_interruptible(&dev->resume_wait);
617		}
618
619		write_ipc_from_queue(dev);
620		break;
621
622	case MNG_RESET_NOTIFY:
623		if (!ishtp_dev) {
624			ishtp_dev = dev;
625		}
626		schedule_work(&fw_reset_work);
627		break;
628
629	case MNG_RESET_NOTIFY_ACK:
630		dev->recvd_hw_ready = 1;
631		wake_up_interruptible(&dev->wait_hw_ready);
632		break;
633	}
634}
635
636/**
637 * ish_irq_handler() - ISH IRQ handler
638 * @irq: irq number
639 * @dev_id: ishtp device pointer
640 *
641 * ISH IRQ handler. If interrupt is generated and is for ISH it will process
642 * the interrupt.
643 */
644irqreturn_t ish_irq_handler(int irq, void *dev_id)
645{
646	struct ishtp_device	*dev = dev_id;
647	uint32_t	doorbell_val;
648	bool	interrupt_generated;
649
650	/* Check that it's interrupt from ISH (may be shared) */
651	interrupt_generated = check_generated_interrupt(dev);
652
653	if (!interrupt_generated)
654		return IRQ_NONE;
655
656	doorbell_val = ish_reg_read(dev, IPC_REG_ISH2HOST_DRBL);
657	if (!IPC_IS_BUSY(doorbell_val))
658		return IRQ_HANDLED;
659
660	if (dev->dev_state == ISHTP_DEV_DISABLED)
661		return	IRQ_HANDLED;
662
663	/* Sanity check: IPC dgram length in header */
664	if (IPC_HEADER_GET_LENGTH(doorbell_val) > IPC_PAYLOAD_SIZE) {
665		dev_err(dev->devc,
666			"IPC hdr - bad length: %u; dropped\n",
667			(unsigned int)IPC_HEADER_GET_LENGTH(doorbell_val));
668		goto	eoi;
669	}
670
671	switch (IPC_HEADER_GET_PROTOCOL(doorbell_val)) {
672	default:
673		break;
674	case IPC_PROTOCOL_MNG:
675		recv_ipc(dev, doorbell_val);
676		break;
677	case IPC_PROTOCOL_ISHTP:
678		ishtp_recv(dev);
679		break;
680	}
681
682eoi:
683	/* Update IPC counters */
684	++dev->ipc_rx_cnt;
685	dev->ipc_rx_bytes_cnt += IPC_HEADER_GET_LENGTH(doorbell_val);
686
687	ish_reg_write(dev, IPC_REG_ISH2HOST_DRBL, 0);
688	/* Flush write to doorbell */
689	ish_reg_read(dev, IPC_REG_ISH_HOST_FWSTS);
690
691	return	IRQ_HANDLED;
692}
693
694/**
695 * ish_disable_dma() - disable dma communication between host and ISHFW
696 * @dev: ishtp device pointer
697 *
698 * Clear the dma enable bit and wait for dma inactive.
699 *
700 * Return: 0 for success else error code.
701 */
702int ish_disable_dma(struct ishtp_device *dev)
703{
704	unsigned int	dma_delay;
705
706	/* Clear the dma enable bit */
707	ish_reg_write(dev, IPC_REG_ISH_RMP2, 0);
708
709	/* wait for dma inactive */
710	for (dma_delay = 0; dma_delay < MAX_DMA_DELAY &&
711		_ish_read_fw_sts_reg(dev) & (IPC_ISH_IN_DMA);
712		dma_delay += 5)
713		mdelay(5);
714
715	if (dma_delay >= MAX_DMA_DELAY) {
716		dev_err(dev->devc,
717			"Wait for DMA inactive timeout\n");
718		return	-EBUSY;
719	}
720
721	return 0;
722}
723
724/**
725 * ish_wakeup() - wakeup ishfw from waiting-for-host state
726 * @dev: ishtp device pointer
727 *
728 * Set the dma enable bit and send a void message to FW,
729 * it wil wakeup FW from waiting-for-host state.
730 */
731static void ish_wakeup(struct ishtp_device *dev)
732{
733	/* Set dma enable bit */
734	ish_reg_write(dev, IPC_REG_ISH_RMP2, IPC_RMP2_DMA_ENABLED);
735
736	/*
737	 * Send 0 IPC message so that ISH FW wakes up if it was already
738	 * asleep.
739	 */
740	ish_reg_write(dev, IPC_REG_HOST2ISH_DRBL, IPC_DRBL_BUSY_BIT);
741
742	/* Flush writes to doorbell and REMAP2 */
743	ish_reg_read(dev, IPC_REG_ISH_HOST_FWSTS);
744}
745
746/**
747 * _ish_hw_reset() - HW reset
748 * @dev: ishtp device pointer
749 *
750 * Reset ISH HW to recover if any error
751 *
752 * Return: 0 for success else error fault code
753 */
754static int _ish_hw_reset(struct ishtp_device *dev)
755{
756	struct pci_dev *pdev = dev->pdev;
757	int	rv;
758	uint16_t csr;
759
760	if (!pdev)
761		return	-ENODEV;
762
763	rv = pci_reset_function(pdev);
764	if (!rv)
765		dev->dev_state = ISHTP_DEV_RESETTING;
766
767	if (!pdev->pm_cap) {
768		dev_err(&pdev->dev, "Can't reset - no PM caps\n");
769		return	-EINVAL;
770	}
771
772	/* Disable dma communication between FW and host */
773	if (ish_disable_dma(dev)) {
774		dev_err(&pdev->dev,
775			"Can't reset - stuck with DMA in-progress\n");
776		return	-EBUSY;
777	}
778
779	pci_read_config_word(pdev, pdev->pm_cap + PCI_PM_CTRL, &csr);
780
781	csr &= ~PCI_PM_CTRL_STATE_MASK;
782	csr |= PCI_D3hot;
783	pci_write_config_word(pdev, pdev->pm_cap + PCI_PM_CTRL, csr);
784
785	mdelay(pdev->d3hot_delay);
786
787	csr &= ~PCI_PM_CTRL_STATE_MASK;
788	csr |= PCI_D0;
789	pci_write_config_word(pdev, pdev->pm_cap + PCI_PM_CTRL, csr);
790
791	/* Now we can enable ISH DMA operation and wakeup ISHFW */
792	ish_wakeup(dev);
793
794	return	0;
795}
796
797/**
798 * _ish_ipc_reset() - IPC reset
799 * @dev: ishtp device pointer
800 *
801 * Resets host and fw IPC and upper layers
802 *
803 * Return: 0 for success else error fault code
804 */
805static int _ish_ipc_reset(struct ishtp_device *dev)
806{
807	struct ipc_rst_payload_type ipc_mng_msg;
808	int	rv = 0;
809
810	ipc_mng_msg.reset_id = 1;
811	ipc_mng_msg.reserved = 0;
812
813	set_host_ready(dev);
814
815	/* Clear the incoming doorbell */
816	ish_reg_write(dev, IPC_REG_ISH2HOST_DRBL, 0);
817	/* Flush write to doorbell */
818	ish_reg_read(dev, IPC_REG_ISH_HOST_FWSTS);
819
820	dev->recvd_hw_ready = 0;
821
822	/* send message */
823	rv = ipc_send_mng_msg(dev, MNG_RESET_NOTIFY, &ipc_mng_msg,
824		sizeof(struct ipc_rst_payload_type));
825	if (rv) {
826		dev_err(dev->devc, "Failed to send IPC MNG_RESET_NOTIFY\n");
827		return	rv;
828	}
829
830	wait_event_interruptible_timeout(dev->wait_hw_ready,
831					 dev->recvd_hw_ready, 2 * HZ);
832	if (!dev->recvd_hw_ready) {
833		dev_err(dev->devc, "Timed out waiting for HW ready\n");
834		rv = -ENODEV;
835	}
836
837	return rv;
838}
839
840/**
841 * ish_hw_start() -Start ISH HW
842 * @dev: ishtp device pointer
843 *
844 * Set host to ready state and wait for FW reset
845 *
846 * Return: 0 for success else error fault code
847 */
848int ish_hw_start(struct ishtp_device *dev)
849{
850	ish_set_host_rdy(dev);
851
852	set_host_ready(dev);
853
854	/* After that we can enable ISH DMA operation and wakeup ISHFW */
855	ish_wakeup(dev);
856
857	/* wait for FW-initiated reset flow */
858	if (!dev->recvd_hw_ready)
859		wait_event_interruptible_timeout(dev->wait_hw_ready,
860						 dev->recvd_hw_ready,
861						 10 * HZ);
862
863	if (!dev->recvd_hw_ready) {
864		dev_err(dev->devc,
865			"[ishtp-ish]: Timed out waiting for FW-initiated reset\n");
866		return	-ENODEV;
867	}
868
869	return 0;
870}
871
872/**
873 * ish_ipc_get_header() -Get doorbell value
874 * @dev: ishtp device pointer
875 * @length: length of message
876 * @busy: busy status
877 *
878 * Get door bell value from message header
879 *
880 * Return: door bell value
881 */
882static uint32_t ish_ipc_get_header(struct ishtp_device *dev, int length,
883				   int busy)
884{
885	uint32_t drbl_val;
886
887	drbl_val = IPC_BUILD_HEADER(length, IPC_PROTOCOL_ISHTP, busy);
888
889	return drbl_val;
890}
891
892/**
893 * _dma_no_cache_snooping()
894 *
895 * Check on current platform, DMA supports cache snooping or not.
896 * This callback is used to notify uplayer driver if manully cache
897 * flush is needed when do DMA operation.
898 *
899 * Please pay attention to this callback implementation, if declare
900 * having cache snooping on a cache snooping not supported platform
901 * will cause uplayer driver receiving mismatched data; and if
902 * declare no cache snooping on a cache snooping supported platform
903 * will cause cache be flushed twice and performance hit.
904 *
905 * @dev: ishtp device pointer
906 *
907 * Return: false - has cache snooping capability
908 *         true - no cache snooping, need manually cache flush
909 */
910static bool _dma_no_cache_snooping(struct ishtp_device *dev)
911{
912	return (dev->pdev->device == EHL_Ax_DEVICE_ID ||
913		dev->pdev->device == TGL_LP_DEVICE_ID ||
914		dev->pdev->device == TGL_H_DEVICE_ID ||
915		dev->pdev->device == ADL_S_DEVICE_ID ||
916		dev->pdev->device == ADL_P_DEVICE_ID);
917}
918
919static const struct ishtp_hw_ops ish_hw_ops = {
920	.hw_reset = _ish_hw_reset,
921	.ipc_reset = _ish_ipc_reset,
922	.ipc_get_header = ish_ipc_get_header,
923	.ishtp_read = _ishtp_read,
924	.write = write_ipc_to_queue,
925	.get_fw_status = _ish_read_fw_sts_reg,
926	.sync_fw_clock = _ish_sync_fw_clock,
927	.ishtp_read_hdr = _ishtp_read_hdr,
928	.dma_no_cache_snooping = _dma_no_cache_snooping
929};
930
931/**
932 * ish_dev_init() -Initialize ISH devoce
933 * @pdev: PCI device
934 *
935 * Allocate ISHTP device and initialize IPC processing
936 *
937 * Return: ISHTP device instance on success else NULL
938 */
939struct ishtp_device *ish_dev_init(struct pci_dev *pdev)
940{
941	struct ishtp_device *dev;
942	int	i;
943	int	ret;
944
945	dev = devm_kzalloc(&pdev->dev,
946			   sizeof(struct ishtp_device) + sizeof(struct ish_hw),
947			   GFP_KERNEL);
948	if (!dev)
949		return NULL;
950
951	dev->devc = &pdev->dev;
952	ishtp_device_init(dev);
953
954	init_waitqueue_head(&dev->wait_hw_ready);
955
956	spin_lock_init(&dev->wr_processing_spinlock);
957
958	/* Init IPC processing and free lists */
959	INIT_LIST_HEAD(&dev->wr_processing_list);
960	INIT_LIST_HEAD(&dev->wr_free_list);
961	for (i = 0; i < IPC_TX_FIFO_SIZE; i++) {
962		struct wr_msg_ctl_info	*tx_buf;
963
964		tx_buf = devm_kzalloc(&pdev->dev,
965				      sizeof(struct wr_msg_ctl_info),
966				      GFP_KERNEL);
967		if (!tx_buf) {
968			/*
969			 * IPC buffers may be limited or not available
970			 * at all - although this shouldn't happen
971			 */
972			dev_err(dev->devc,
973				"[ishtp-ish]: failure in Tx FIFO allocations (%d)\n",
974				i);
975			break;
976		}
977		list_add_tail(&tx_buf->link, &dev->wr_free_list);
978	}
979
980	ret = devm_work_autocancel(&pdev->dev, &fw_reset_work, fw_reset_work_fn);
981	if (ret) {
982		dev_err(dev->devc, "Failed to initialise FW reset work\n");
983		return NULL;
984	}
985
986	dev->ops = &ish_hw_ops;
987	dev->mtu = IPC_PAYLOAD_SIZE - sizeof(struct ishtp_msg_hdr);
988	return dev;
989}
990
991/**
992 * ish_device_disable() - Disable ISH device
993 * @dev: ISHTP device pointer
994 *
995 * Disable ISH by clearing host ready to inform firmware.
996 */
997void	ish_device_disable(struct ishtp_device *dev)
998{
999	struct pci_dev *pdev = dev->pdev;
1000
1001	if (!pdev)
1002		return;
1003
1004	/* Disable dma communication between FW and host */
1005	if (ish_disable_dma(dev)) {
1006		dev_err(&pdev->dev,
1007			"Can't reset - stuck with DMA in-progress\n");
1008		return;
1009	}
1010
1011	/* Put ISH to D3hot state for power saving */
1012	pci_set_power_state(pdev, PCI_D3hot);
1013
1014	dev->dev_state = ISHTP_DEV_DISABLED;
1015	ish_clr_host_rdy(dev);
1016}
1017