xref: /openbmc/linux/drivers/mailbox/imx-mailbox.c (revision 55eb9a6c)
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_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/suspend.h>
20 #include <linux/slab.h>
21 
22 #define IMX_MU_CHANS		16
23 /* TX0/RX0/RXDB[0-3] */
24 #define IMX_MU_SCU_CHANS	6
25 /* TX0/RX0 */
26 #define IMX_MU_S4_CHANS		2
27 #define IMX_MU_CHAN_NAME_SIZE	20
28 
29 #define IMX_MU_SECO_TX_TOUT (msecs_to_jiffies(3000))
30 #define IMX_MU_SECO_RX_TOUT (msecs_to_jiffies(3000))
31 
32 /* Please not change TX & RX */
33 enum imx_mu_chan_type {
34 	IMX_MU_TYPE_TX		= 0, /* Tx */
35 	IMX_MU_TYPE_RX		= 1, /* Rx */
36 	IMX_MU_TYPE_TXDB	= 2, /* Tx doorbell */
37 	IMX_MU_TYPE_RXDB	= 3, /* Rx doorbell */
38 };
39 
40 enum imx_mu_xcr {
41 	IMX_MU_GIER,
42 	IMX_MU_GCR,
43 	IMX_MU_TCR,
44 	IMX_MU_RCR,
45 	IMX_MU_xCR_MAX,
46 };
47 
48 enum imx_mu_xsr {
49 	IMX_MU_SR,
50 	IMX_MU_GSR,
51 	IMX_MU_TSR,
52 	IMX_MU_RSR,
53 };
54 
55 struct imx_sc_rpc_msg_max {
56 	struct imx_sc_rpc_msg hdr;
57 	u32 data[30];
58 };
59 
60 struct imx_s4_rpc_msg_max {
61 	struct imx_s4_rpc_msg hdr;
62 	u32 data[254];
63 };
64 
65 struct imx_mu_con_priv {
66 	unsigned int		idx;
67 	char			irq_desc[IMX_MU_CHAN_NAME_SIZE];
68 	enum imx_mu_chan_type	type;
69 	struct mbox_chan	*chan;
70 	struct tasklet_struct	txdb_tasklet;
71 };
72 
73 struct imx_mu_priv {
74 	struct device		*dev;
75 	void __iomem		*base;
76 	void			*msg;
77 	spinlock_t		xcr_lock; /* control register lock */
78 
79 	struct mbox_controller	mbox;
80 	struct mbox_chan	mbox_chans[IMX_MU_CHANS];
81 
82 	struct imx_mu_con_priv  con_priv[IMX_MU_CHANS];
83 	const struct imx_mu_dcfg	*dcfg;
84 	struct clk		*clk;
85 	int			irq[IMX_MU_CHANS];
86 	bool			suspend;
87 
88 	u32 xcr[4];
89 
90 	bool			side_b;
91 };
92 
93 enum imx_mu_type {
94 	IMX_MU_V1,
95 	IMX_MU_V2 = BIT(1),
96 	IMX_MU_V2_S4 = BIT(15),
97 	IMX_MU_V2_IRQ = BIT(16),
98 };
99 
100 struct imx_mu_dcfg {
101 	int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
102 	int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
103 	int (*rxdb)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
104 	void (*init)(struct imx_mu_priv *priv);
105 	enum imx_mu_type type;
106 	u32	xTR;		/* Transmit Register0 */
107 	u32	xRR;		/* Receive Register0 */
108 	u32	xSR[4];		/* Status Registers */
109 	u32	xCR[4];		/* Control Registers */
110 };
111 
112 #define IMX_MU_xSR_GIPn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
113 #define IMX_MU_xSR_RFn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
114 #define IMX_MU_xSR_TEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
115 
116 /* General Purpose Interrupt Enable */
117 #define IMX_MU_xCR_GIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
118 /* Receive Interrupt Enable */
119 #define IMX_MU_xCR_RIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
120 /* Transmit Interrupt Enable */
121 #define IMX_MU_xCR_TIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
122 /* General Purpose Interrupt Request */
123 #define IMX_MU_xCR_GIRn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(16 + (3 - (x))))
124 
125 
126 static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
127 {
128 	return container_of(mbox, struct imx_mu_priv, mbox);
129 }
130 
131 static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
132 {
133 	iowrite32(val, priv->base + offs);
134 }
135 
136 static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
137 {
138 	return ioread32(priv->base + offs);
139 }
140 
141 static int imx_mu_tx_waiting_write(struct imx_mu_priv *priv, u32 val, u32 idx)
142 {
143 	u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_TX_TOUT;
144 	u32 status;
145 	u32 can_write;
146 
147 	dev_dbg(priv->dev, "Trying to write %.8x to idx %d\n", val, idx);
148 
149 	do {
150 		status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
151 		can_write = status & IMX_MU_xSR_TEn(priv->dcfg->type, idx % 4);
152 	} while (!can_write && time_is_after_jiffies64(timeout_time));
153 
154 	if (!can_write) {
155 		dev_err(priv->dev, "timeout trying to write %.8x at %d(%.8x)\n",
156 			val, idx, status);
157 		return -ETIME;
158 	}
159 
160 	imx_mu_write(priv, val, priv->dcfg->xTR + (idx % 4) * 4);
161 
162 	return 0;
163 }
164 
165 static int imx_mu_rx_waiting_read(struct imx_mu_priv *priv, u32 *val, u32 idx)
166 {
167 	u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_RX_TOUT;
168 	u32 status;
169 	u32 can_read;
170 
171 	dev_dbg(priv->dev, "Trying to read from idx %d\n", idx);
172 
173 	do {
174 		status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
175 		can_read = status & IMX_MU_xSR_RFn(priv->dcfg->type, idx % 4);
176 	} while (!can_read && time_is_after_jiffies64(timeout_time));
177 
178 	if (!can_read) {
179 		dev_err(priv->dev, "timeout trying to read idx %d (%.8x)\n",
180 			idx, status);
181 		return -ETIME;
182 	}
183 
184 	*val = imx_mu_read(priv, priv->dcfg->xRR + (idx % 4) * 4);
185 	dev_dbg(priv->dev, "Read %.8x\n", *val);
186 
187 	return 0;
188 }
189 
190 static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, enum imx_mu_xcr type, u32 set, u32 clr)
191 {
192 	unsigned long flags;
193 	u32 val;
194 
195 	spin_lock_irqsave(&priv->xcr_lock, flags);
196 	val = imx_mu_read(priv, priv->dcfg->xCR[type]);
197 	val &= ~clr;
198 	val |= set;
199 	imx_mu_write(priv, val, priv->dcfg->xCR[type]);
200 	spin_unlock_irqrestore(&priv->xcr_lock, flags);
201 
202 	return val;
203 }
204 
205 static int imx_mu_generic_tx(struct imx_mu_priv *priv,
206 			     struct imx_mu_con_priv *cp,
207 			     void *data)
208 {
209 	u32 *arg = data;
210 
211 	switch (cp->type) {
212 	case IMX_MU_TYPE_TX:
213 		imx_mu_write(priv, *arg, priv->dcfg->xTR + cp->idx * 4);
214 		imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
215 		break;
216 	case IMX_MU_TYPE_TXDB:
217 		imx_mu_xcr_rmw(priv, IMX_MU_GCR, IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
218 		tasklet_schedule(&cp->txdb_tasklet);
219 		break;
220 	default:
221 		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
222 		return -EINVAL;
223 	}
224 
225 	return 0;
226 }
227 
228 static int imx_mu_generic_rx(struct imx_mu_priv *priv,
229 			     struct imx_mu_con_priv *cp)
230 {
231 	u32 dat;
232 
233 	dat = imx_mu_read(priv, priv->dcfg->xRR + (cp->idx) * 4);
234 	mbox_chan_received_data(cp->chan, (void *)&dat);
235 
236 	return 0;
237 }
238 
239 static int imx_mu_generic_rxdb(struct imx_mu_priv *priv,
240 			       struct imx_mu_con_priv *cp)
241 {
242 	imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
243 		     priv->dcfg->xSR[IMX_MU_GSR]);
244 	mbox_chan_received_data(cp->chan, NULL);
245 
246 	return 0;
247 }
248 
249 static int imx_mu_specific_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data)
250 {
251 	u32 *arg = data;
252 	int i, ret;
253 	u32 xsr;
254 	u32 size, max_size, num_tr;
255 
256 	if (priv->dcfg->type & IMX_MU_V2_S4) {
257 		size = ((struct imx_s4_rpc_msg_max *)data)->hdr.size;
258 		max_size = sizeof(struct imx_s4_rpc_msg_max);
259 		num_tr = 8;
260 	} else {
261 		size = ((struct imx_sc_rpc_msg_max *)data)->hdr.size;
262 		max_size = sizeof(struct imx_sc_rpc_msg_max);
263 		num_tr = 4;
264 	}
265 
266 	switch (cp->type) {
267 	case IMX_MU_TYPE_TX:
268 		/*
269 		 * msg->hdr.size specifies the number of u32 words while
270 		 * sizeof yields bytes.
271 		 */
272 
273 		if (size > max_size / 4) {
274 			/*
275 			 * The real message size can be different to
276 			 * struct imx_sc_rpc_msg_max/imx_s4_rpc_msg_max size
277 			 */
278 			dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on TX; got: %i bytes\n", max_size, size << 2);
279 			return -EINVAL;
280 		}
281 
282 		for (i = 0; i < num_tr && i < size; i++)
283 			imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
284 		for (; i < size; i++) {
285 			ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_TSR],
286 						 xsr,
287 						 xsr & IMX_MU_xSR_TEn(priv->dcfg->type, i % num_tr),
288 						 0, 5 * USEC_PER_SEC);
289 			if (ret) {
290 				dev_err(priv->dev, "Send data index: %d timeout\n", i);
291 				return ret;
292 			}
293 			imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
294 		}
295 
296 		imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
297 		break;
298 	default:
299 		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
300 		return -EINVAL;
301 	}
302 
303 	return 0;
304 }
305 
306 static int imx_mu_specific_rx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
307 {
308 	u32 *data;
309 	int i, ret;
310 	u32 xsr;
311 	u32 size, max_size;
312 
313 	data = (u32 *)priv->msg;
314 
315 	imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, 0));
316 	*data++ = imx_mu_read(priv, priv->dcfg->xRR);
317 
318 	if (priv->dcfg->type & IMX_MU_V2_S4) {
319 		size = ((struct imx_s4_rpc_msg_max *)priv->msg)->hdr.size;
320 		max_size = sizeof(struct imx_s4_rpc_msg_max);
321 	} else {
322 		size = ((struct imx_sc_rpc_msg_max *)priv->msg)->hdr.size;
323 		max_size = sizeof(struct imx_sc_rpc_msg_max);
324 	}
325 
326 	if (size > max_size / 4) {
327 		dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on RX; got: %i bytes\n", max_size, size << 2);
328 		return -EINVAL;
329 	}
330 
331 	for (i = 1; i < size; i++) {
332 		ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_RSR], xsr,
333 					 xsr & IMX_MU_xSR_RFn(priv->dcfg->type, i % 4), 0,
334 					 5 * USEC_PER_SEC);
335 		if (ret) {
336 			dev_err(priv->dev, "timeout read idx %d\n", i);
337 			return ret;
338 		}
339 		*data++ = imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
340 	}
341 
342 	imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, 0), 0);
343 	mbox_chan_received_data(cp->chan, (void *)priv->msg);
344 
345 	return 0;
346 }
347 
348 static int imx_mu_seco_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp,
349 			  void *data)
350 {
351 	struct imx_sc_rpc_msg_max *msg = data;
352 	u32 *arg = data;
353 	u32 byte_size;
354 	int err;
355 	int i;
356 
357 	dev_dbg(priv->dev, "Sending message\n");
358 
359 	switch (cp->type) {
360 	case IMX_MU_TYPE_TXDB:
361 		byte_size = msg->hdr.size * sizeof(u32);
362 		if (byte_size > sizeof(*msg)) {
363 			/*
364 			 * The real message size can be different to
365 			 * struct imx_sc_rpc_msg_max size
366 			 */
367 			dev_err(priv->dev,
368 				"Exceed max msg size (%zu) on TX, got: %i\n",
369 				sizeof(*msg), byte_size);
370 			return -EINVAL;
371 		}
372 
373 		print_hex_dump_debug("from client ", DUMP_PREFIX_OFFSET, 4, 4,
374 				     data, byte_size, false);
375 
376 		/* Send first word */
377 		dev_dbg(priv->dev, "Sending header\n");
378 		imx_mu_write(priv, *arg++, priv->dcfg->xTR);
379 
380 		/* Send signaling */
381 		dev_dbg(priv->dev, "Sending signaling\n");
382 		imx_mu_xcr_rmw(priv, IMX_MU_GCR,
383 			       IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
384 
385 		/* Send words to fill the mailbox */
386 		for (i = 1; i < 4 && i < msg->hdr.size; i++) {
387 			dev_dbg(priv->dev, "Sending word %d\n", i);
388 			imx_mu_write(priv, *arg++,
389 				     priv->dcfg->xTR + (i % 4) * 4);
390 		}
391 
392 		/* Send rest of message waiting for remote read */
393 		for (; i < msg->hdr.size; i++) {
394 			dev_dbg(priv->dev, "Sending word %d\n", i);
395 			err = imx_mu_tx_waiting_write(priv, *arg++, i);
396 			if (err) {
397 				dev_err(priv->dev, "Timeout tx %d\n", i);
398 				return err;
399 			}
400 		}
401 
402 		/* Simulate hack for mbox framework */
403 		tasklet_schedule(&cp->txdb_tasklet);
404 
405 		break;
406 	default:
407 		dev_warn_ratelimited(priv->dev,
408 				     "Send data on wrong channel type: %d\n",
409 				     cp->type);
410 		return -EINVAL;
411 	}
412 
413 	return 0;
414 }
415 
416 static int imx_mu_seco_rxdb(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
417 {
418 	struct imx_sc_rpc_msg_max msg;
419 	u32 *data = (u32 *)&msg;
420 	u32 byte_size;
421 	int err = 0;
422 	int i;
423 
424 	dev_dbg(priv->dev, "Receiving message\n");
425 
426 	/* Read header */
427 	dev_dbg(priv->dev, "Receiving header\n");
428 	*data++ = imx_mu_read(priv, priv->dcfg->xRR);
429 	byte_size = msg.hdr.size * sizeof(u32);
430 	if (byte_size > sizeof(msg)) {
431 		dev_err(priv->dev, "Exceed max msg size (%zu) on RX, got: %i\n",
432 			sizeof(msg), byte_size);
433 		err = -EINVAL;
434 		goto error;
435 	}
436 
437 	/* Read message waiting they are written */
438 	for (i = 1; i < msg.hdr.size; i++) {
439 		dev_dbg(priv->dev, "Receiving word %d\n", i);
440 		err = imx_mu_rx_waiting_read(priv, data++, i);
441 		if (err) {
442 			dev_err(priv->dev, "Timeout rx %d\n", i);
443 			goto error;
444 		}
445 	}
446 
447 	/* Clear GIP */
448 	imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
449 		     priv->dcfg->xSR[IMX_MU_GSR]);
450 
451 	print_hex_dump_debug("to client ", DUMP_PREFIX_OFFSET, 4, 4,
452 			     &msg, byte_size, false);
453 
454 	/* send data to client */
455 	dev_dbg(priv->dev, "Sending message to client\n");
456 	mbox_chan_received_data(cp->chan, (void *)&msg);
457 
458 	goto exit;
459 
460 error:
461 	mbox_chan_received_data(cp->chan, ERR_PTR(err));
462 
463 exit:
464 	return err;
465 }
466 
467 static void imx_mu_txdb_tasklet(unsigned long data)
468 {
469 	struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
470 
471 	mbox_chan_txdone(cp->chan, 0);
472 }
473 
474 static irqreturn_t imx_mu_isr(int irq, void *p)
475 {
476 	struct mbox_chan *chan = p;
477 	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
478 	struct imx_mu_con_priv *cp = chan->con_priv;
479 	u32 val, ctrl;
480 
481 	switch (cp->type) {
482 	case IMX_MU_TYPE_TX:
483 		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_TCR]);
484 		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
485 		val &= IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx) &
486 			(ctrl & IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
487 		break;
488 	case IMX_MU_TYPE_RX:
489 		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_RCR]);
490 		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
491 		val &= IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx) &
492 			(ctrl & IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
493 		break;
494 	case IMX_MU_TYPE_RXDB:
495 		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_GIER]);
496 		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_GSR]);
497 		val &= IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx) &
498 			(ctrl & IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
499 		break;
500 	default:
501 		dev_warn_ratelimited(priv->dev, "Unhandled channel type %d\n",
502 				     cp->type);
503 		return IRQ_NONE;
504 	}
505 
506 	if (!val)
507 		return IRQ_NONE;
508 
509 	if ((val == IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx)) &&
510 	    (cp->type == IMX_MU_TYPE_TX)) {
511 		imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
512 		mbox_chan_txdone(chan, 0);
513 	} else if ((val == IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx)) &&
514 		   (cp->type == IMX_MU_TYPE_RX)) {
515 		priv->dcfg->rx(priv, cp);
516 	} else if ((val == IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx)) &&
517 		   (cp->type == IMX_MU_TYPE_RXDB)) {
518 		priv->dcfg->rxdb(priv, cp);
519 	} else {
520 		dev_warn_ratelimited(priv->dev, "Not handled interrupt\n");
521 		return IRQ_NONE;
522 	}
523 
524 	if (priv->suspend)
525 		pm_system_wakeup();
526 
527 	return IRQ_HANDLED;
528 }
529 
530 static int imx_mu_send_data(struct mbox_chan *chan, void *data)
531 {
532 	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
533 	struct imx_mu_con_priv *cp = chan->con_priv;
534 
535 	return priv->dcfg->tx(priv, cp, data);
536 }
537 
538 static int imx_mu_startup(struct mbox_chan *chan)
539 {
540 	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
541 	struct imx_mu_con_priv *cp = chan->con_priv;
542 	unsigned long irq_flag = 0;
543 	int ret;
544 
545 	pm_runtime_get_sync(priv->dev);
546 	if (cp->type == IMX_MU_TYPE_TXDB) {
547 		/* Tx doorbell don't have ACK support */
548 		tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
549 			     (unsigned long)cp);
550 		return 0;
551 	}
552 
553 	/* IPC MU should be with IRQF_NO_SUSPEND set */
554 	if (!priv->dev->pm_domain)
555 		irq_flag |= IRQF_NO_SUSPEND;
556 
557 	if (!(priv->dcfg->type & IMX_MU_V2_IRQ))
558 		irq_flag |= IRQF_SHARED;
559 
560 	ret = request_irq(priv->irq[cp->type], imx_mu_isr, irq_flag, cp->irq_desc, chan);
561 	if (ret) {
562 		dev_err(priv->dev, "Unable to acquire IRQ %d\n", priv->irq[cp->type]);
563 		return ret;
564 	}
565 
566 	switch (cp->type) {
567 	case IMX_MU_TYPE_RX:
568 		imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx), 0);
569 		break;
570 	case IMX_MU_TYPE_RXDB:
571 		imx_mu_xcr_rmw(priv, IMX_MU_GIER, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx), 0);
572 		break;
573 	default:
574 		break;
575 	}
576 
577 	return 0;
578 }
579 
580 static void imx_mu_shutdown(struct mbox_chan *chan)
581 {
582 	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
583 	struct imx_mu_con_priv *cp = chan->con_priv;
584 
585 	if (cp->type == IMX_MU_TYPE_TXDB) {
586 		tasklet_kill(&cp->txdb_tasklet);
587 		pm_runtime_put_sync(priv->dev);
588 		return;
589 	}
590 
591 	switch (cp->type) {
592 	case IMX_MU_TYPE_TX:
593 		imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
594 		break;
595 	case IMX_MU_TYPE_RX:
596 		imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
597 		break;
598 	case IMX_MU_TYPE_RXDB:
599 		imx_mu_xcr_rmw(priv, IMX_MU_GIER, 0, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
600 		break;
601 	default:
602 		break;
603 	}
604 
605 	free_irq(priv->irq[cp->type], chan);
606 	pm_runtime_put_sync(priv->dev);
607 }
608 
609 static const struct mbox_chan_ops imx_mu_ops = {
610 	.send_data = imx_mu_send_data,
611 	.startup = imx_mu_startup,
612 	.shutdown = imx_mu_shutdown,
613 };
614 
615 static struct mbox_chan *imx_mu_specific_xlate(struct mbox_controller *mbox,
616 					       const struct of_phandle_args *sp)
617 {
618 	u32 type, idx, chan;
619 
620 	if (sp->args_count != 2) {
621 		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
622 		return ERR_PTR(-EINVAL);
623 	}
624 
625 	type = sp->args[0]; /* channel type */
626 	idx = sp->args[1]; /* index */
627 
628 	switch (type) {
629 	case IMX_MU_TYPE_TX:
630 	case IMX_MU_TYPE_RX:
631 		if (idx != 0)
632 			dev_err(mbox->dev, "Invalid chan idx: %d\n", idx);
633 		chan = type;
634 		break;
635 	case IMX_MU_TYPE_RXDB:
636 		chan = 2 + idx;
637 		break;
638 	default:
639 		dev_err(mbox->dev, "Invalid chan type: %d\n", type);
640 		return ERR_PTR(-EINVAL);
641 	}
642 
643 	if (chan >= mbox->num_chans) {
644 		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
645 		return ERR_PTR(-EINVAL);
646 	}
647 
648 	return &mbox->chans[chan];
649 }
650 
651 static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox,
652 				       const struct of_phandle_args *sp)
653 {
654 	u32 type, idx, chan;
655 
656 	if (sp->args_count != 2) {
657 		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
658 		return ERR_PTR(-EINVAL);
659 	}
660 
661 	type = sp->args[0]; /* channel type */
662 	idx = sp->args[1]; /* index */
663 	chan = type * 4 + idx;
664 
665 	if (chan >= mbox->num_chans) {
666 		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
667 		return ERR_PTR(-EINVAL);
668 	}
669 
670 	return &mbox->chans[chan];
671 }
672 
673 static struct mbox_chan *imx_mu_seco_xlate(struct mbox_controller *mbox,
674 					   const struct of_phandle_args *sp)
675 {
676 	u32 type;
677 
678 	if (sp->args_count < 1) {
679 		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
680 		return ERR_PTR(-EINVAL);
681 	}
682 
683 	type = sp->args[0]; /* channel type */
684 
685 	/* Only supports TXDB and RXDB */
686 	if (type == IMX_MU_TYPE_TX || type == IMX_MU_TYPE_RX) {
687 		dev_err(mbox->dev, "Invalid type: %d\n", type);
688 		return ERR_PTR(-EINVAL);
689 	}
690 
691 	return imx_mu_xlate(mbox, sp);
692 }
693 
694 static void imx_mu_init_generic(struct imx_mu_priv *priv)
695 {
696 	unsigned int i;
697 
698 	for (i = 0; i < IMX_MU_CHANS; i++) {
699 		struct imx_mu_con_priv *cp = &priv->con_priv[i];
700 
701 		cp->idx = i % 4;
702 		cp->type = i >> 2;
703 		cp->chan = &priv->mbox_chans[i];
704 		priv->mbox_chans[i].con_priv = cp;
705 		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
706 			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
707 	}
708 
709 	priv->mbox.num_chans = IMX_MU_CHANS;
710 	priv->mbox.of_xlate = imx_mu_xlate;
711 
712 	if (priv->side_b)
713 		return;
714 
715 	/* Set default MU configuration */
716 	for (i = 0; i < IMX_MU_xCR_MAX; i++)
717 		imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
718 }
719 
720 static void imx_mu_init_specific(struct imx_mu_priv *priv)
721 {
722 	unsigned int i;
723 	int num_chans = priv->dcfg->type & IMX_MU_V2_S4 ? IMX_MU_S4_CHANS : IMX_MU_SCU_CHANS;
724 
725 	for (i = 0; i < num_chans; i++) {
726 		struct imx_mu_con_priv *cp = &priv->con_priv[i];
727 
728 		cp->idx = i < 2 ? 0 : i - 2;
729 		cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB;
730 		cp->chan = &priv->mbox_chans[i];
731 		priv->mbox_chans[i].con_priv = cp;
732 		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
733 			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
734 	}
735 
736 	priv->mbox.num_chans = num_chans;
737 	priv->mbox.of_xlate = imx_mu_specific_xlate;
738 
739 	/* Set default MU configuration */
740 	for (i = 0; i < IMX_MU_xCR_MAX; i++)
741 		imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
742 }
743 
744 static void imx_mu_init_seco(struct imx_mu_priv *priv)
745 {
746 	imx_mu_init_generic(priv);
747 	priv->mbox.of_xlate = imx_mu_seco_xlate;
748 }
749 
750 static int imx_mu_probe(struct platform_device *pdev)
751 {
752 	struct device *dev = &pdev->dev;
753 	struct device_node *np = dev->of_node;
754 	struct imx_mu_priv *priv;
755 	const struct imx_mu_dcfg *dcfg;
756 	int i, ret;
757 	u32 size;
758 
759 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
760 	if (!priv)
761 		return -ENOMEM;
762 
763 	priv->dev = dev;
764 
765 	priv->base = devm_platform_ioremap_resource(pdev, 0);
766 	if (IS_ERR(priv->base))
767 		return PTR_ERR(priv->base);
768 
769 	dcfg = of_device_get_match_data(dev);
770 	if (!dcfg)
771 		return -EINVAL;
772 	priv->dcfg = dcfg;
773 	if (priv->dcfg->type & IMX_MU_V2_IRQ) {
774 		priv->irq[IMX_MU_TYPE_TX] = platform_get_irq_byname(pdev, "tx");
775 		if (priv->irq[IMX_MU_TYPE_TX] < 0)
776 			return priv->irq[IMX_MU_TYPE_TX];
777 		priv->irq[IMX_MU_TYPE_RX] = platform_get_irq_byname(pdev, "rx");
778 		if (priv->irq[IMX_MU_TYPE_RX] < 0)
779 			return priv->irq[IMX_MU_TYPE_RX];
780 	} else {
781 		ret = platform_get_irq(pdev, 0);
782 		if (ret < 0)
783 			return ret;
784 
785 		for (i = 0; i < IMX_MU_CHANS; i++)
786 			priv->irq[i] = ret;
787 	}
788 
789 	if (priv->dcfg->type & IMX_MU_V2_S4)
790 		size = sizeof(struct imx_s4_rpc_msg_max);
791 	else
792 		size = sizeof(struct imx_sc_rpc_msg_max);
793 
794 	priv->msg = devm_kzalloc(dev, size, GFP_KERNEL);
795 	if (!priv->msg)
796 		return -ENOMEM;
797 
798 	priv->clk = devm_clk_get(dev, NULL);
799 	if (IS_ERR(priv->clk)) {
800 		if (PTR_ERR(priv->clk) != -ENOENT)
801 			return PTR_ERR(priv->clk);
802 
803 		priv->clk = NULL;
804 	}
805 
806 	ret = clk_prepare_enable(priv->clk);
807 	if (ret) {
808 		dev_err(dev, "Failed to enable clock\n");
809 		return ret;
810 	}
811 
812 	priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
813 
814 	priv->dcfg->init(priv);
815 
816 	spin_lock_init(&priv->xcr_lock);
817 
818 	priv->mbox.dev = dev;
819 	priv->mbox.ops = &imx_mu_ops;
820 	priv->mbox.chans = priv->mbox_chans;
821 	priv->mbox.txdone_irq = true;
822 
823 	platform_set_drvdata(pdev, priv);
824 
825 	ret = devm_mbox_controller_register(dev, &priv->mbox);
826 	if (ret) {
827 		clk_disable_unprepare(priv->clk);
828 		return ret;
829 	}
830 
831 	pm_runtime_enable(dev);
832 
833 	ret = pm_runtime_resume_and_get(dev);
834 	if (ret < 0)
835 		goto disable_runtime_pm;
836 
837 	ret = pm_runtime_put_sync(dev);
838 	if (ret < 0)
839 		goto disable_runtime_pm;
840 
841 	clk_disable_unprepare(priv->clk);
842 
843 	return 0;
844 
845 disable_runtime_pm:
846 	pm_runtime_disable(dev);
847 	clk_disable_unprepare(priv->clk);
848 	return ret;
849 }
850 
851 static int imx_mu_remove(struct platform_device *pdev)
852 {
853 	struct imx_mu_priv *priv = platform_get_drvdata(pdev);
854 
855 	pm_runtime_disable(priv->dev);
856 
857 	return 0;
858 }
859 
860 static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
861 	.tx	= imx_mu_generic_tx,
862 	.rx	= imx_mu_generic_rx,
863 	.rxdb	= imx_mu_generic_rxdb,
864 	.init	= imx_mu_init_generic,
865 	.xTR	= 0x0,
866 	.xRR	= 0x10,
867 	.xSR	= {0x20, 0x20, 0x20, 0x20},
868 	.xCR	= {0x24, 0x24, 0x24, 0x24},
869 };
870 
871 static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
872 	.tx	= imx_mu_generic_tx,
873 	.rx	= imx_mu_generic_rx,
874 	.rxdb	= imx_mu_generic_rxdb,
875 	.init	= imx_mu_init_generic,
876 	.xTR	= 0x20,
877 	.xRR	= 0x40,
878 	.xSR	= {0x60, 0x60, 0x60, 0x60},
879 	.xCR	= {0x64, 0x64, 0x64, 0x64},
880 };
881 
882 static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp = {
883 	.tx	= imx_mu_generic_tx,
884 	.rx	= imx_mu_generic_rx,
885 	.rxdb	= imx_mu_generic_rxdb,
886 	.init	= imx_mu_init_generic,
887 	.type	= IMX_MU_V2,
888 	.xTR	= 0x200,
889 	.xRR	= 0x280,
890 	.xSR	= {0xC, 0x118, 0x124, 0x12C},
891 	.xCR	= {0x110, 0x114, 0x120, 0x128},
892 };
893 
894 static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp_s4 = {
895 	.tx	= imx_mu_specific_tx,
896 	.rx	= imx_mu_specific_rx,
897 	.init	= imx_mu_init_specific,
898 	.type	= IMX_MU_V2 | IMX_MU_V2_S4,
899 	.xTR	= 0x200,
900 	.xRR	= 0x280,
901 	.xSR	= {0xC, 0x118, 0x124, 0x12C},
902 	.xCR	= {0x110, 0x114, 0x120, 0x128},
903 };
904 
905 static const struct imx_mu_dcfg imx_mu_cfg_imx93_s4 = {
906 	.tx	= imx_mu_specific_tx,
907 	.rx	= imx_mu_specific_rx,
908 	.init	= imx_mu_init_specific,
909 	.type	= IMX_MU_V2 | IMX_MU_V2_S4 | IMX_MU_V2_IRQ,
910 	.xTR	= 0x200,
911 	.xRR	= 0x280,
912 	.xSR	= {0xC, 0x118, 0x124, 0x12C},
913 	.xCR	= {0x110, 0x114, 0x120, 0x128},
914 };
915 
916 static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = {
917 	.tx	= imx_mu_specific_tx,
918 	.rx	= imx_mu_specific_rx,
919 	.init	= imx_mu_init_specific,
920 	.rxdb	= imx_mu_generic_rxdb,
921 	.xTR	= 0x0,
922 	.xRR	= 0x10,
923 	.xSR	= {0x20, 0x20, 0x20, 0x20},
924 	.xCR	= {0x24, 0x24, 0x24, 0x24},
925 };
926 
927 static const struct imx_mu_dcfg imx_mu_cfg_imx8_seco = {
928 	.tx	= imx_mu_seco_tx,
929 	.rx	= imx_mu_generic_rx,
930 	.rxdb	= imx_mu_seco_rxdb,
931 	.init	= imx_mu_init_seco,
932 	.xTR	= 0x0,
933 	.xRR	= 0x10,
934 	.xSR	= {0x20, 0x20, 0x20, 0x20},
935 	.xCR	= {0x24, 0x24, 0x24, 0x24},
936 };
937 
938 static const struct of_device_id imx_mu_dt_ids[] = {
939 	{ .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },
940 	{ .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx },
941 	{ .compatible = "fsl,imx8ulp-mu", .data = &imx_mu_cfg_imx8ulp },
942 	{ .compatible = "fsl,imx8ulp-mu-s4", .data = &imx_mu_cfg_imx8ulp_s4 },
943 	{ .compatible = "fsl,imx93-mu-s4", .data = &imx_mu_cfg_imx93_s4 },
944 	{ .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu },
945 	{ .compatible = "fsl,imx8-mu-seco", .data = &imx_mu_cfg_imx8_seco },
946 	{ },
947 };
948 MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
949 
950 static int __maybe_unused imx_mu_suspend_noirq(struct device *dev)
951 {
952 	struct imx_mu_priv *priv = dev_get_drvdata(dev);
953 	int i;
954 
955 	if (!priv->clk) {
956 		for (i = 0; i < IMX_MU_xCR_MAX; i++)
957 			priv->xcr[i] = imx_mu_read(priv, priv->dcfg->xCR[i]);
958 	}
959 
960 	priv->suspend = true;
961 
962 	return 0;
963 }
964 
965 static int __maybe_unused imx_mu_resume_noirq(struct device *dev)
966 {
967 	struct imx_mu_priv *priv = dev_get_drvdata(dev);
968 	int i;
969 
970 	/*
971 	 * ONLY restore MU when context lost, the TIE could
972 	 * be set during noirq resume as there is MU data
973 	 * communication going on, and restore the saved
974 	 * value will overwrite the TIE and cause MU data
975 	 * send failed, may lead to system freeze. This issue
976 	 * is observed by testing freeze mode suspend.
977 	 */
978 	if (!priv->clk && !imx_mu_read(priv, priv->dcfg->xCR[0])) {
979 		for (i = 0; i < IMX_MU_xCR_MAX; i++)
980 			imx_mu_write(priv, priv->xcr[i], priv->dcfg->xCR[i]);
981 	}
982 
983 	priv->suspend = false;
984 
985 	return 0;
986 }
987 
988 static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
989 {
990 	struct imx_mu_priv *priv = dev_get_drvdata(dev);
991 
992 	clk_disable_unprepare(priv->clk);
993 
994 	return 0;
995 }
996 
997 static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
998 {
999 	struct imx_mu_priv *priv = dev_get_drvdata(dev);
1000 	int ret;
1001 
1002 	ret = clk_prepare_enable(priv->clk);
1003 	if (ret)
1004 		dev_err(dev, "failed to enable clock\n");
1005 
1006 	return ret;
1007 }
1008 
1009 static const struct dev_pm_ops imx_mu_pm_ops = {
1010 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq,
1011 				      imx_mu_resume_noirq)
1012 	SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
1013 			   imx_mu_runtime_resume, NULL)
1014 };
1015 
1016 static struct platform_driver imx_mu_driver = {
1017 	.probe		= imx_mu_probe,
1018 	.remove		= imx_mu_remove,
1019 	.driver = {
1020 		.name	= "imx_mu",
1021 		.of_match_table = imx_mu_dt_ids,
1022 		.pm = &imx_mu_pm_ops,
1023 	},
1024 };
1025 module_platform_driver(imx_mu_driver);
1026 
1027 MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
1028 MODULE_DESCRIPTION("Message Unit driver for i.MX");
1029 MODULE_LICENSE("GPL v2");
1030