1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de>
4 * Copyright 2022 NXP, Peng Fan <peng.fan@nxp.com>
5 */
6
7#include <linux/clk.h>
8#include <linux/firmware/imx/ipc.h>
9#include <linux/firmware/imx/s4.h>
10#include <linux/interrupt.h>
11#include <linux/io.h>
12#include <linux/iopoll.h>
13#include <linux/jiffies.h>
14#include <linux/kernel.h>
15#include <linux/mailbox_controller.h>
16#include <linux/module.h>
17#include <linux/of.h>
18#include <linux/platform_device.h>
19#include <linux/pm_runtime.h>
20#include <linux/suspend.h>
21#include <linux/slab.h>
22
23#define IMX_MU_CHANS		17
24/* TX0/RX0/RXDB[0-3] */
25#define IMX_MU_SCU_CHANS	6
26/* TX0/RX0 */
27#define IMX_MU_S4_CHANS		2
28#define IMX_MU_CHAN_NAME_SIZE	20
29
30#define IMX_MU_NUM_RR		4
31
32#define IMX_MU_SECO_TX_TOUT (msecs_to_jiffies(3000))
33#define IMX_MU_SECO_RX_TOUT (msecs_to_jiffies(3000))
34
35/* Please not change TX & RX */
36enum imx_mu_chan_type {
37	IMX_MU_TYPE_TX		= 0, /* Tx */
38	IMX_MU_TYPE_RX		= 1, /* Rx */
39	IMX_MU_TYPE_TXDB	= 2, /* Tx doorbell */
40	IMX_MU_TYPE_RXDB	= 3, /* Rx doorbell */
41	IMX_MU_TYPE_RST		= 4, /* Reset */
42};
43
44enum imx_mu_xcr {
45	IMX_MU_CR,
46	IMX_MU_GIER,
47	IMX_MU_GCR,
48	IMX_MU_TCR,
49	IMX_MU_RCR,
50	IMX_MU_xCR_MAX,
51};
52
53enum imx_mu_xsr {
54	IMX_MU_SR,
55	IMX_MU_GSR,
56	IMX_MU_TSR,
57	IMX_MU_RSR,
58	IMX_MU_xSR_MAX,
59};
60
61struct imx_sc_rpc_msg_max {
62	struct imx_sc_rpc_msg hdr;
63	u32 data[30];
64};
65
66struct imx_s4_rpc_msg_max {
67	struct imx_s4_rpc_msg hdr;
68	u32 data[254];
69};
70
71struct imx_mu_con_priv {
72	unsigned int		idx;
73	char			irq_desc[IMX_MU_CHAN_NAME_SIZE];
74	enum imx_mu_chan_type	type;
75	struct mbox_chan	*chan;
76	struct tasklet_struct	txdb_tasklet;
77};
78
79struct imx_mu_priv {
80	struct device		*dev;
81	void __iomem		*base;
82	void			*msg;
83	spinlock_t		xcr_lock; /* control register lock */
84
85	struct mbox_controller	mbox;
86	struct mbox_chan	mbox_chans[IMX_MU_CHANS];
87
88	struct imx_mu_con_priv  con_priv[IMX_MU_CHANS];
89	const struct imx_mu_dcfg	*dcfg;
90	struct clk		*clk;
91	int			irq[IMX_MU_CHANS];
92	bool			suspend;
93
94	u32 xcr[IMX_MU_xCR_MAX];
95
96	bool			side_b;
97};
98
99enum imx_mu_type {
100	IMX_MU_V1,
101	IMX_MU_V2 = BIT(1),
102	IMX_MU_V2_S4 = BIT(15),
103	IMX_MU_V2_IRQ = BIT(16),
104};
105
106struct imx_mu_dcfg {
107	int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
108	int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
109	int (*rxdb)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
110	void (*init)(struct imx_mu_priv *priv);
111	enum imx_mu_type type;
112	u32	xTR;		/* Transmit Register0 */
113	u32	xRR;		/* Receive Register0 */
114	u32	xSR[IMX_MU_xSR_MAX];	/* Status Registers */
115	u32	xCR[IMX_MU_xCR_MAX];	/* Control Registers */
116};
117
118#define IMX_MU_xSR_GIPn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
119#define IMX_MU_xSR_RFn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
120#define IMX_MU_xSR_TEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
121
122/* General Purpose Interrupt Enable */
123#define IMX_MU_xCR_GIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
124/* Receive Interrupt Enable */
125#define IMX_MU_xCR_RIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
126/* Transmit Interrupt Enable */
127#define IMX_MU_xCR_TIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
128/* General Purpose Interrupt Request */
129#define IMX_MU_xCR_GIRn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(16 + (3 - (x))))
130/* MU reset */
131#define IMX_MU_xCR_RST(type)	(type & IMX_MU_V2 ? BIT(0) : BIT(5))
132#define IMX_MU_xSR_RST(type)	(type & IMX_MU_V2 ? BIT(0) : BIT(7))
133
134
135static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
136{
137	return container_of(mbox, struct imx_mu_priv, mbox);
138}
139
140static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
141{
142	iowrite32(val, priv->base + offs);
143}
144
145static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
146{
147	return ioread32(priv->base + offs);
148}
149
150static int imx_mu_tx_waiting_write(struct imx_mu_priv *priv, u32 val, u32 idx)
151{
152	u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_TX_TOUT;
153	u32 status;
154	u32 can_write;
155
156	dev_dbg(priv->dev, "Trying to write %.8x to idx %d\n", val, idx);
157
158	do {
159		status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
160		can_write = status & IMX_MU_xSR_TEn(priv->dcfg->type, idx % 4);
161	} while (!can_write && time_is_after_jiffies64(timeout_time));
162
163	if (!can_write) {
164		dev_err(priv->dev, "timeout trying to write %.8x at %d(%.8x)\n",
165			val, idx, status);
166		return -ETIME;
167	}
168
169	imx_mu_write(priv, val, priv->dcfg->xTR + (idx % 4) * 4);
170
171	return 0;
172}
173
174static int imx_mu_rx_waiting_read(struct imx_mu_priv *priv, u32 *val, u32 idx)
175{
176	u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_RX_TOUT;
177	u32 status;
178	u32 can_read;
179
180	dev_dbg(priv->dev, "Trying to read from idx %d\n", idx);
181
182	do {
183		status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
184		can_read = status & IMX_MU_xSR_RFn(priv->dcfg->type, idx % 4);
185	} while (!can_read && time_is_after_jiffies64(timeout_time));
186
187	if (!can_read) {
188		dev_err(priv->dev, "timeout trying to read idx %d (%.8x)\n",
189			idx, status);
190		return -ETIME;
191	}
192
193	*val = imx_mu_read(priv, priv->dcfg->xRR + (idx % 4) * 4);
194	dev_dbg(priv->dev, "Read %.8x\n", *val);
195
196	return 0;
197}
198
199static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, enum imx_mu_xcr type, u32 set, u32 clr)
200{
201	unsigned long flags;
202	u32 val;
203
204	spin_lock_irqsave(&priv->xcr_lock, flags);
205	val = imx_mu_read(priv, priv->dcfg->xCR[type]);
206	val &= ~clr;
207	val |= set;
208	imx_mu_write(priv, val, priv->dcfg->xCR[type]);
209	spin_unlock_irqrestore(&priv->xcr_lock, flags);
210
211	return val;
212}
213
214static int imx_mu_generic_tx(struct imx_mu_priv *priv,
215			     struct imx_mu_con_priv *cp,
216			     void *data)
217{
218	u32 *arg = data;
219
220	switch (cp->type) {
221	case IMX_MU_TYPE_TX:
222		imx_mu_write(priv, *arg, priv->dcfg->xTR + cp->idx * 4);
223		imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
224		break;
225	case IMX_MU_TYPE_TXDB:
226		imx_mu_xcr_rmw(priv, IMX_MU_GCR, IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
227		tasklet_schedule(&cp->txdb_tasklet);
228		break;
229	default:
230		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
231		return -EINVAL;
232	}
233
234	return 0;
235}
236
237static int imx_mu_generic_rx(struct imx_mu_priv *priv,
238			     struct imx_mu_con_priv *cp)
239{
240	u32 dat;
241
242	dat = imx_mu_read(priv, priv->dcfg->xRR + (cp->idx) * 4);
243	mbox_chan_received_data(cp->chan, (void *)&dat);
244
245	return 0;
246}
247
248static int imx_mu_generic_rxdb(struct imx_mu_priv *priv,
249			       struct imx_mu_con_priv *cp)
250{
251	imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
252		     priv->dcfg->xSR[IMX_MU_GSR]);
253	mbox_chan_received_data(cp->chan, NULL);
254
255	return 0;
256}
257
258static int imx_mu_specific_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data)
259{
260	u32 *arg = data;
261	int i, ret;
262	u32 xsr;
263	u32 size, max_size, num_tr;
264
265	if (priv->dcfg->type & IMX_MU_V2_S4) {
266		size = ((struct imx_s4_rpc_msg_max *)data)->hdr.size;
267		max_size = sizeof(struct imx_s4_rpc_msg_max);
268		num_tr = 8;
269	} else {
270		size = ((struct imx_sc_rpc_msg_max *)data)->hdr.size;
271		max_size = sizeof(struct imx_sc_rpc_msg_max);
272		num_tr = 4;
273	}
274
275	switch (cp->type) {
276	case IMX_MU_TYPE_TX:
277		/*
278		 * msg->hdr.size specifies the number of u32 words while
279		 * sizeof yields bytes.
280		 */
281
282		if (size > max_size / 4) {
283			/*
284			 * The real message size can be different to
285			 * struct imx_sc_rpc_msg_max/imx_s4_rpc_msg_max size
286			 */
287			dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on TX; got: %i bytes\n", max_size, size << 2);
288			return -EINVAL;
289		}
290
291		for (i = 0; i < num_tr && i < size; i++)
292			imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
293		for (; i < size; i++) {
294			ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_TSR],
295						 xsr,
296						 xsr & IMX_MU_xSR_TEn(priv->dcfg->type, i % num_tr),
297						 0, 5 * USEC_PER_SEC);
298			if (ret) {
299				dev_err(priv->dev, "Send data index: %d timeout\n", i);
300				return ret;
301			}
302			imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
303		}
304
305		imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
306		break;
307	default:
308		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
309		return -EINVAL;
310	}
311
312	return 0;
313}
314
315static int imx_mu_specific_rx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
316{
317	u32 *data;
318	int i, ret;
319	u32 xsr;
320	u32 size, max_size;
321
322	data = (u32 *)priv->msg;
323
324	imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, 0));
325	*data++ = imx_mu_read(priv, priv->dcfg->xRR);
326
327	if (priv->dcfg->type & IMX_MU_V2_S4) {
328		size = ((struct imx_s4_rpc_msg_max *)priv->msg)->hdr.size;
329		max_size = sizeof(struct imx_s4_rpc_msg_max);
330	} else {
331		size = ((struct imx_sc_rpc_msg_max *)priv->msg)->hdr.size;
332		max_size = sizeof(struct imx_sc_rpc_msg_max);
333	}
334
335	if (size > max_size / 4) {
336		dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on RX; got: %i bytes\n", max_size, size << 2);
337		return -EINVAL;
338	}
339
340	for (i = 1; i < size; i++) {
341		ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_RSR], xsr,
342					 xsr & IMX_MU_xSR_RFn(priv->dcfg->type, i % 4), 0,
343					 5 * USEC_PER_SEC);
344		if (ret) {
345			dev_err(priv->dev, "timeout read idx %d\n", i);
346			return ret;
347		}
348		*data++ = imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
349	}
350
351	imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, 0), 0);
352	mbox_chan_received_data(cp->chan, (void *)priv->msg);
353
354	return 0;
355}
356
357static int imx_mu_seco_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp,
358			  void *data)
359{
360	struct imx_sc_rpc_msg_max *msg = data;
361	u32 *arg = data;
362	u32 byte_size;
363	int err;
364	int i;
365
366	dev_dbg(priv->dev, "Sending message\n");
367
368	switch (cp->type) {
369	case IMX_MU_TYPE_TXDB:
370		byte_size = msg->hdr.size * sizeof(u32);
371		if (byte_size > sizeof(*msg)) {
372			/*
373			 * The real message size can be different to
374			 * struct imx_sc_rpc_msg_max size
375			 */
376			dev_err(priv->dev,
377				"Exceed max msg size (%zu) on TX, got: %i\n",
378				sizeof(*msg), byte_size);
379			return -EINVAL;
380		}
381
382		print_hex_dump_debug("from client ", DUMP_PREFIX_OFFSET, 4, 4,
383				     data, byte_size, false);
384
385		/* Send first word */
386		dev_dbg(priv->dev, "Sending header\n");
387		imx_mu_write(priv, *arg++, priv->dcfg->xTR);
388
389		/* Send signaling */
390		dev_dbg(priv->dev, "Sending signaling\n");
391		imx_mu_xcr_rmw(priv, IMX_MU_GCR,
392			       IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
393
394		/* Send words to fill the mailbox */
395		for (i = 1; i < 4 && i < msg->hdr.size; i++) {
396			dev_dbg(priv->dev, "Sending word %d\n", i);
397			imx_mu_write(priv, *arg++,
398				     priv->dcfg->xTR + (i % 4) * 4);
399		}
400
401		/* Send rest of message waiting for remote read */
402		for (; i < msg->hdr.size; i++) {
403			dev_dbg(priv->dev, "Sending word %d\n", i);
404			err = imx_mu_tx_waiting_write(priv, *arg++, i);
405			if (err) {
406				dev_err(priv->dev, "Timeout tx %d\n", i);
407				return err;
408			}
409		}
410
411		/* Simulate hack for mbox framework */
412		tasklet_schedule(&cp->txdb_tasklet);
413
414		break;
415	default:
416		dev_warn_ratelimited(priv->dev,
417				     "Send data on wrong channel type: %d\n",
418				     cp->type);
419		return -EINVAL;
420	}
421
422	return 0;
423}
424
425static int imx_mu_seco_rxdb(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
426{
427	struct imx_sc_rpc_msg_max msg;
428	u32 *data = (u32 *)&msg;
429	u32 byte_size;
430	int err = 0;
431	int i;
432
433	dev_dbg(priv->dev, "Receiving message\n");
434
435	/* Read header */
436	dev_dbg(priv->dev, "Receiving header\n");
437	*data++ = imx_mu_read(priv, priv->dcfg->xRR);
438	byte_size = msg.hdr.size * sizeof(u32);
439	if (byte_size > sizeof(msg)) {
440		dev_err(priv->dev, "Exceed max msg size (%zu) on RX, got: %i\n",
441			sizeof(msg), byte_size);
442		err = -EINVAL;
443		goto error;
444	}
445
446	/* Read message waiting they are written */
447	for (i = 1; i < msg.hdr.size; i++) {
448		dev_dbg(priv->dev, "Receiving word %d\n", i);
449		err = imx_mu_rx_waiting_read(priv, data++, i);
450		if (err) {
451			dev_err(priv->dev, "Timeout rx %d\n", i);
452			goto error;
453		}
454	}
455
456	/* Clear GIP */
457	imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
458		     priv->dcfg->xSR[IMX_MU_GSR]);
459
460	print_hex_dump_debug("to client ", DUMP_PREFIX_OFFSET, 4, 4,
461			     &msg, byte_size, false);
462
463	/* send data to client */
464	dev_dbg(priv->dev, "Sending message to client\n");
465	mbox_chan_received_data(cp->chan, (void *)&msg);
466
467	goto exit;
468
469error:
470	mbox_chan_received_data(cp->chan, ERR_PTR(err));
471
472exit:
473	return err;
474}
475
476static void imx_mu_txdb_tasklet(unsigned long data)
477{
478	struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
479
480	mbox_chan_txdone(cp->chan, 0);
481}
482
483static irqreturn_t imx_mu_isr(int irq, void *p)
484{
485	struct mbox_chan *chan = p;
486	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
487	struct imx_mu_con_priv *cp = chan->con_priv;
488	u32 val, ctrl;
489
490	switch (cp->type) {
491	case IMX_MU_TYPE_TX:
492		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_TCR]);
493		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
494		val &= IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx) &
495			(ctrl & IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
496		break;
497	case IMX_MU_TYPE_RX:
498		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_RCR]);
499		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
500		val &= IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx) &
501			(ctrl & IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
502		break;
503	case IMX_MU_TYPE_RXDB:
504		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_GIER]);
505		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_GSR]);
506		val &= IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx) &
507			(ctrl & IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
508		break;
509	case IMX_MU_TYPE_RST:
510		return IRQ_NONE;
511	default:
512		dev_warn_ratelimited(priv->dev, "Unhandled channel type %d\n",
513				     cp->type);
514		return IRQ_NONE;
515	}
516
517	if (!val)
518		return IRQ_NONE;
519
520	if ((val == IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx)) &&
521	    (cp->type == IMX_MU_TYPE_TX)) {
522		imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
523		mbox_chan_txdone(chan, 0);
524	} else if ((val == IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx)) &&
525		   (cp->type == IMX_MU_TYPE_RX)) {
526		priv->dcfg->rx(priv, cp);
527	} else if ((val == IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx)) &&
528		   (cp->type == IMX_MU_TYPE_RXDB)) {
529		priv->dcfg->rxdb(priv, cp);
530	} else {
531		dev_warn_ratelimited(priv->dev, "Not handled interrupt\n");
532		return IRQ_NONE;
533	}
534
535	if (priv->suspend)
536		pm_system_wakeup();
537
538	return IRQ_HANDLED;
539}
540
541static int imx_mu_send_data(struct mbox_chan *chan, void *data)
542{
543	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
544	struct imx_mu_con_priv *cp = chan->con_priv;
545
546	return priv->dcfg->tx(priv, cp, data);
547}
548
549static int imx_mu_startup(struct mbox_chan *chan)
550{
551	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
552	struct imx_mu_con_priv *cp = chan->con_priv;
553	unsigned long irq_flag = 0;
554	int ret;
555
556	pm_runtime_get_sync(priv->dev);
557	if (cp->type == IMX_MU_TYPE_TXDB) {
558		/* Tx doorbell don't have ACK support */
559		tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
560			     (unsigned long)cp);
561		return 0;
562	}
563
564	/* IPC MU should be with IRQF_NO_SUSPEND set */
565	if (!priv->dev->pm_domain)
566		irq_flag |= IRQF_NO_SUSPEND;
567
568	if (!(priv->dcfg->type & IMX_MU_V2_IRQ))
569		irq_flag |= IRQF_SHARED;
570
571	ret = request_irq(priv->irq[cp->type], imx_mu_isr, irq_flag, cp->irq_desc, chan);
572	if (ret) {
573		dev_err(priv->dev, "Unable to acquire IRQ %d\n", priv->irq[cp->type]);
574		return ret;
575	}
576
577	switch (cp->type) {
578	case IMX_MU_TYPE_RX:
579		imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx), 0);
580		break;
581	case IMX_MU_TYPE_RXDB:
582		imx_mu_xcr_rmw(priv, IMX_MU_GIER, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx), 0);
583		break;
584	default:
585		break;
586	}
587
588	return 0;
589}
590
591static void imx_mu_shutdown(struct mbox_chan *chan)
592{
593	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
594	struct imx_mu_con_priv *cp = chan->con_priv;
595	int ret;
596	u32 sr;
597
598	if (cp->type == IMX_MU_TYPE_TXDB) {
599		tasklet_kill(&cp->txdb_tasklet);
600		pm_runtime_put_sync(priv->dev);
601		return;
602	}
603
604	switch (cp->type) {
605	case IMX_MU_TYPE_TX:
606		imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
607		break;
608	case IMX_MU_TYPE_RX:
609		imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
610		break;
611	case IMX_MU_TYPE_RXDB:
612		imx_mu_xcr_rmw(priv, IMX_MU_GIER, 0, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
613		break;
614	case IMX_MU_TYPE_RST:
615		imx_mu_xcr_rmw(priv, IMX_MU_CR, IMX_MU_xCR_RST(priv->dcfg->type), 0);
616		ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_SR], sr,
617					 !(sr & IMX_MU_xSR_RST(priv->dcfg->type)), 1, 5);
618		if (ret)
619			dev_warn(priv->dev, "RST channel timeout\n");
620		break;
621	default:
622		break;
623	}
624
625	free_irq(priv->irq[cp->type], chan);
626	pm_runtime_put_sync(priv->dev);
627}
628
629static const struct mbox_chan_ops imx_mu_ops = {
630	.send_data = imx_mu_send_data,
631	.startup = imx_mu_startup,
632	.shutdown = imx_mu_shutdown,
633};
634
635static struct mbox_chan *imx_mu_specific_xlate(struct mbox_controller *mbox,
636					       const struct of_phandle_args *sp)
637{
638	u32 type, idx, chan;
639
640	if (sp->args_count != 2) {
641		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
642		return ERR_PTR(-EINVAL);
643	}
644
645	type = sp->args[0]; /* channel type */
646	idx = sp->args[1]; /* index */
647
648	switch (type) {
649	case IMX_MU_TYPE_TX:
650	case IMX_MU_TYPE_RX:
651		if (idx != 0)
652			dev_err(mbox->dev, "Invalid chan idx: %d\n", idx);
653		chan = type;
654		break;
655	case IMX_MU_TYPE_RXDB:
656		chan = 2 + idx;
657		break;
658	default:
659		dev_err(mbox->dev, "Invalid chan type: %d\n", type);
660		return ERR_PTR(-EINVAL);
661	}
662
663	if (chan >= mbox->num_chans) {
664		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
665		return ERR_PTR(-EINVAL);
666	}
667
668	return &mbox->chans[chan];
669}
670
671static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox,
672				       const struct of_phandle_args *sp)
673{
674	u32 type, idx, chan;
675
676	if (sp->args_count != 2) {
677		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
678		return ERR_PTR(-EINVAL);
679	}
680
681	type = sp->args[0]; /* channel type */
682	idx = sp->args[1]; /* index */
683	chan = type * 4 + idx;
684
685	if (chan >= mbox->num_chans) {
686		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
687		return ERR_PTR(-EINVAL);
688	}
689
690	return &mbox->chans[chan];
691}
692
693static struct mbox_chan *imx_mu_seco_xlate(struct mbox_controller *mbox,
694					   const struct of_phandle_args *sp)
695{
696	u32 type;
697
698	if (sp->args_count < 1) {
699		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
700		return ERR_PTR(-EINVAL);
701	}
702
703	type = sp->args[0]; /* channel type */
704
705	/* Only supports TXDB and RXDB */
706	if (type == IMX_MU_TYPE_TX || type == IMX_MU_TYPE_RX) {
707		dev_err(mbox->dev, "Invalid type: %d\n", type);
708		return ERR_PTR(-EINVAL);
709	}
710
711	return imx_mu_xlate(mbox, sp);
712}
713
714static void imx_mu_init_generic(struct imx_mu_priv *priv)
715{
716	unsigned int i;
717	unsigned int val;
718
719	for (i = 0; i < IMX_MU_CHANS; i++) {
720		struct imx_mu_con_priv *cp = &priv->con_priv[i];
721
722		cp->idx = i % 4;
723		cp->type = i >> 2;
724		cp->chan = &priv->mbox_chans[i];
725		priv->mbox_chans[i].con_priv = cp;
726		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
727			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
728	}
729
730	priv->mbox.num_chans = IMX_MU_CHANS;
731	priv->mbox.of_xlate = imx_mu_xlate;
732
733	if (priv->side_b)
734		return;
735
736	/* Set default MU configuration */
737	for (i = 0; i < IMX_MU_xCR_MAX; i++)
738		imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
739
740	/* Clear any pending GIP */
741	val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_GSR]);
742	imx_mu_write(priv, val, priv->dcfg->xSR[IMX_MU_GSR]);
743
744	/* Clear any pending RSR */
745	for (i = 0; i < IMX_MU_NUM_RR; i++)
746		imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
747}
748
749static void imx_mu_init_specific(struct imx_mu_priv *priv)
750{
751	unsigned int i;
752	int num_chans = priv->dcfg->type & IMX_MU_V2_S4 ? IMX_MU_S4_CHANS : IMX_MU_SCU_CHANS;
753
754	for (i = 0; i < num_chans; i++) {
755		struct imx_mu_con_priv *cp = &priv->con_priv[i];
756
757		cp->idx = i < 2 ? 0 : i - 2;
758		cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB;
759		cp->chan = &priv->mbox_chans[i];
760		priv->mbox_chans[i].con_priv = cp;
761		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
762			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
763	}
764
765	priv->mbox.num_chans = num_chans;
766	priv->mbox.of_xlate = imx_mu_specific_xlate;
767
768	/* Set default MU configuration */
769	for (i = 0; i < IMX_MU_xCR_MAX; i++)
770		imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
771}
772
773static void imx_mu_init_seco(struct imx_mu_priv *priv)
774{
775	imx_mu_init_generic(priv);
776	priv->mbox.of_xlate = imx_mu_seco_xlate;
777}
778
779static int imx_mu_probe(struct platform_device *pdev)
780{
781	struct device *dev = &pdev->dev;
782	struct device_node *np = dev->of_node;
783	struct imx_mu_priv *priv;
784	const struct imx_mu_dcfg *dcfg;
785	int i, ret;
786	u32 size;
787
788	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
789	if (!priv)
790		return -ENOMEM;
791
792	priv->dev = dev;
793
794	priv->base = devm_platform_ioremap_resource(pdev, 0);
795	if (IS_ERR(priv->base))
796		return PTR_ERR(priv->base);
797
798	dcfg = of_device_get_match_data(dev);
799	if (!dcfg)
800		return -EINVAL;
801	priv->dcfg = dcfg;
802	if (priv->dcfg->type & IMX_MU_V2_IRQ) {
803		priv->irq[IMX_MU_TYPE_TX] = platform_get_irq_byname(pdev, "tx");
804		if (priv->irq[IMX_MU_TYPE_TX] < 0)
805			return priv->irq[IMX_MU_TYPE_TX];
806		priv->irq[IMX_MU_TYPE_RX] = platform_get_irq_byname(pdev, "rx");
807		if (priv->irq[IMX_MU_TYPE_RX] < 0)
808			return priv->irq[IMX_MU_TYPE_RX];
809	} else {
810		ret = platform_get_irq(pdev, 0);
811		if (ret < 0)
812			return ret;
813
814		for (i = 0; i < IMX_MU_CHANS; i++)
815			priv->irq[i] = ret;
816	}
817
818	if (priv->dcfg->type & IMX_MU_V2_S4)
819		size = sizeof(struct imx_s4_rpc_msg_max);
820	else
821		size = sizeof(struct imx_sc_rpc_msg_max);
822
823	priv->msg = devm_kzalloc(dev, size, GFP_KERNEL);
824	if (!priv->msg)
825		return -ENOMEM;
826
827	priv->clk = devm_clk_get(dev, NULL);
828	if (IS_ERR(priv->clk)) {
829		if (PTR_ERR(priv->clk) != -ENOENT)
830			return PTR_ERR(priv->clk);
831
832		priv->clk = NULL;
833	}
834
835	ret = clk_prepare_enable(priv->clk);
836	if (ret) {
837		dev_err(dev, "Failed to enable clock\n");
838		return ret;
839	}
840
841	priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
842
843	priv->dcfg->init(priv);
844
845	spin_lock_init(&priv->xcr_lock);
846
847	priv->mbox.dev = dev;
848	priv->mbox.ops = &imx_mu_ops;
849	priv->mbox.chans = priv->mbox_chans;
850	priv->mbox.txdone_irq = true;
851
852	platform_set_drvdata(pdev, priv);
853
854	ret = devm_mbox_controller_register(dev, &priv->mbox);
855	if (ret) {
856		clk_disable_unprepare(priv->clk);
857		return ret;
858	}
859
860	pm_runtime_enable(dev);
861
862	ret = pm_runtime_resume_and_get(dev);
863	if (ret < 0)
864		goto disable_runtime_pm;
865
866	ret = pm_runtime_put_sync(dev);
867	if (ret < 0)
868		goto disable_runtime_pm;
869
870	clk_disable_unprepare(priv->clk);
871
872	return 0;
873
874disable_runtime_pm:
875	pm_runtime_disable(dev);
876	clk_disable_unprepare(priv->clk);
877	return ret;
878}
879
880static int imx_mu_remove(struct platform_device *pdev)
881{
882	struct imx_mu_priv *priv = platform_get_drvdata(pdev);
883
884	pm_runtime_disable(priv->dev);
885
886	return 0;
887}
888
889static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
890	.tx	= imx_mu_generic_tx,
891	.rx	= imx_mu_generic_rx,
892	.rxdb	= imx_mu_generic_rxdb,
893	.init	= imx_mu_init_generic,
894	.xTR	= 0x0,
895	.xRR	= 0x10,
896	.xSR	= {0x20, 0x20, 0x20, 0x20},
897	.xCR	= {0x24, 0x24, 0x24, 0x24, 0x24},
898};
899
900static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
901	.tx	= imx_mu_generic_tx,
902	.rx	= imx_mu_generic_rx,
903	.rxdb	= imx_mu_generic_rxdb,
904	.init	= imx_mu_init_generic,
905	.xTR	= 0x20,
906	.xRR	= 0x40,
907	.xSR	= {0x60, 0x60, 0x60, 0x60},
908	.xCR	= {0x64, 0x64, 0x64, 0x64, 0x64},
909};
910
911static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp = {
912	.tx	= imx_mu_generic_tx,
913	.rx	= imx_mu_generic_rx,
914	.rxdb	= imx_mu_generic_rxdb,
915	.init	= imx_mu_init_generic,
916	.type	= IMX_MU_V2,
917	.xTR	= 0x200,
918	.xRR	= 0x280,
919	.xSR	= {0xC, 0x118, 0x124, 0x12C},
920	.xCR	= {0x8, 0x110, 0x114, 0x120, 0x128},
921};
922
923static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp_s4 = {
924	.tx	= imx_mu_specific_tx,
925	.rx	= imx_mu_specific_rx,
926	.init	= imx_mu_init_specific,
927	.type	= IMX_MU_V2 | IMX_MU_V2_S4,
928	.xTR	= 0x200,
929	.xRR	= 0x280,
930	.xSR	= {0xC, 0x118, 0x124, 0x12C},
931	.xCR	= {0x8, 0x110, 0x114, 0x120, 0x128},
932};
933
934static const struct imx_mu_dcfg imx_mu_cfg_imx93_s4 = {
935	.tx	= imx_mu_specific_tx,
936	.rx	= imx_mu_specific_rx,
937	.init	= imx_mu_init_specific,
938	.type	= IMX_MU_V2 | IMX_MU_V2_S4 | IMX_MU_V2_IRQ,
939	.xTR	= 0x200,
940	.xRR	= 0x280,
941	.xSR	= {0xC, 0x118, 0x124, 0x12C},
942	.xCR	= {0x8, 0x110, 0x114, 0x120, 0x128},
943};
944
945static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = {
946	.tx	= imx_mu_specific_tx,
947	.rx	= imx_mu_specific_rx,
948	.init	= imx_mu_init_specific,
949	.rxdb	= imx_mu_generic_rxdb,
950	.xTR	= 0x0,
951	.xRR	= 0x10,
952	.xSR	= {0x20, 0x20, 0x20, 0x20},
953	.xCR	= {0x24, 0x24, 0x24, 0x24, 0x24},
954};
955
956static const struct imx_mu_dcfg imx_mu_cfg_imx8_seco = {
957	.tx	= imx_mu_seco_tx,
958	.rx	= imx_mu_generic_rx,
959	.rxdb	= imx_mu_seco_rxdb,
960	.init	= imx_mu_init_seco,
961	.xTR	= 0x0,
962	.xRR	= 0x10,
963	.xSR	= {0x20, 0x20, 0x20, 0x20},
964	.xCR	= {0x24, 0x24, 0x24, 0x24, 0x24},
965};
966
967static const struct of_device_id imx_mu_dt_ids[] = {
968	{ .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },
969	{ .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx },
970	{ .compatible = "fsl,imx8ulp-mu", .data = &imx_mu_cfg_imx8ulp },
971	{ .compatible = "fsl,imx8ulp-mu-s4", .data = &imx_mu_cfg_imx8ulp_s4 },
972	{ .compatible = "fsl,imx93-mu-s4", .data = &imx_mu_cfg_imx93_s4 },
973	{ .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu },
974	{ .compatible = "fsl,imx8-mu-seco", .data = &imx_mu_cfg_imx8_seco },
975	{ },
976};
977MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
978
979static int __maybe_unused imx_mu_suspend_noirq(struct device *dev)
980{
981	struct imx_mu_priv *priv = dev_get_drvdata(dev);
982	int i;
983
984	if (!priv->clk) {
985		for (i = 0; i < IMX_MU_xCR_MAX; i++)
986			priv->xcr[i] = imx_mu_read(priv, priv->dcfg->xCR[i]);
987	}
988
989	priv->suspend = true;
990
991	return 0;
992}
993
994static int __maybe_unused imx_mu_resume_noirq(struct device *dev)
995{
996	struct imx_mu_priv *priv = dev_get_drvdata(dev);
997	int i;
998
999	/*
1000	 * ONLY restore MU when context lost, the TIE could
1001	 * be set during noirq resume as there is MU data
1002	 * communication going on, and restore the saved
1003	 * value will overwrite the TIE and cause MU data
1004	 * send failed, may lead to system freeze. This issue
1005	 * is observed by testing freeze mode suspend.
1006	 */
1007	if (!priv->clk && !imx_mu_read(priv, priv->dcfg->xCR[0])) {
1008		for (i = 0; i < IMX_MU_xCR_MAX; i++)
1009			imx_mu_write(priv, priv->xcr[i], priv->dcfg->xCR[i]);
1010	}
1011
1012	priv->suspend = false;
1013
1014	return 0;
1015}
1016
1017static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
1018{
1019	struct imx_mu_priv *priv = dev_get_drvdata(dev);
1020
1021	clk_disable_unprepare(priv->clk);
1022
1023	return 0;
1024}
1025
1026static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
1027{
1028	struct imx_mu_priv *priv = dev_get_drvdata(dev);
1029	int ret;
1030
1031	ret = clk_prepare_enable(priv->clk);
1032	if (ret)
1033		dev_err(dev, "failed to enable clock\n");
1034
1035	return ret;
1036}
1037
1038static const struct dev_pm_ops imx_mu_pm_ops = {
1039	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq,
1040				      imx_mu_resume_noirq)
1041	SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
1042			   imx_mu_runtime_resume, NULL)
1043};
1044
1045static struct platform_driver imx_mu_driver = {
1046	.probe		= imx_mu_probe,
1047	.remove		= imx_mu_remove,
1048	.driver = {
1049		.name	= "imx_mu",
1050		.of_match_table = imx_mu_dt_ids,
1051		.pm = &imx_mu_pm_ops,
1052	},
1053};
1054module_platform_driver(imx_mu_driver);
1055
1056MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
1057MODULE_DESCRIPTION("Message Unit driver for i.MX");
1058MODULE_LICENSE("GPL v2");
1059