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v6.8
   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#include "mailbox.h"
 
 
 
  24
  25#define IMX_MU_CHANS		24
 
 
 
 
 
 
 
 
 
  26/* TX0/RX0/RXDB[0-3] */
  27#define IMX_MU_SCU_CHANS	6
  28/* TX0/RX0 */
  29#define IMX_MU_S4_CHANS		2
  30#define IMX_MU_CHAN_NAME_SIZE	20
  31
  32#define IMX_MU_NUM_RR		4
  33
  34#define IMX_MU_SECO_TX_TOUT (msecs_to_jiffies(3000))
  35#define IMX_MU_SECO_RX_TOUT (msecs_to_jiffies(3000))
  36
  37/* Please not change TX & RX */
  38enum imx_mu_chan_type {
  39	IMX_MU_TYPE_TX		= 0, /* Tx */
  40	IMX_MU_TYPE_RX		= 1, /* Rx */
  41	IMX_MU_TYPE_TXDB	= 2, /* Tx doorbell */
  42	IMX_MU_TYPE_RXDB	= 3, /* Rx doorbell */
  43	IMX_MU_TYPE_RST		= 4, /* Reset */
  44	IMX_MU_TYPE_TXDB_V2	= 5, /* Tx doorbell with S/W ACK */
  45};
  46
  47enum imx_mu_xcr {
  48	IMX_MU_CR,
  49	IMX_MU_GIER,
  50	IMX_MU_GCR,
  51	IMX_MU_TCR,
  52	IMX_MU_RCR,
  53	IMX_MU_xCR_MAX,
  54};
  55
  56enum imx_mu_xsr {
  57	IMX_MU_SR,
  58	IMX_MU_GSR,
  59	IMX_MU_TSR,
  60	IMX_MU_RSR,
  61	IMX_MU_xSR_MAX,
  62};
  63
  64struct imx_sc_rpc_msg_max {
  65	struct imx_sc_rpc_msg hdr;
  66	u32 data[30];
  67};
  68
  69struct imx_s4_rpc_msg_max {
  70	struct imx_s4_rpc_msg hdr;
  71	u32 data[254];
  72};
  73
  74struct imx_mu_con_priv {
  75	unsigned int		idx;
  76	char			irq_desc[IMX_MU_CHAN_NAME_SIZE];
  77	enum imx_mu_chan_type	type;
  78	struct mbox_chan	*chan;
  79	struct tasklet_struct	txdb_tasklet;
  80};
  81
  82struct imx_mu_priv {
  83	struct device		*dev;
  84	void __iomem		*base;
  85	void			*msg;
  86	spinlock_t		xcr_lock; /* control register lock */
  87
  88	struct mbox_controller	mbox;
  89	struct mbox_chan	mbox_chans[IMX_MU_CHANS];
  90
  91	struct imx_mu_con_priv  con_priv[IMX_MU_CHANS];
  92	const struct imx_mu_dcfg	*dcfg;
  93	struct clk		*clk;
  94	int			irq[IMX_MU_CHANS];
  95	bool			suspend;
  96
  97	u32 xcr[IMX_MU_xCR_MAX];
  98
  99	bool			side_b;
 100};
 101
 102enum imx_mu_type {
 103	IMX_MU_V1,
 104	IMX_MU_V2 = BIT(1),
 105	IMX_MU_V2_S4 = BIT(15),
 106	IMX_MU_V2_IRQ = BIT(16),
 107};
 108
 109struct imx_mu_dcfg {
 110	int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
 111	int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
 112	int (*rxdb)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
 113	void (*init)(struct imx_mu_priv *priv);
 114	enum imx_mu_type type;
 115	u32	xTR;		/* Transmit Register0 */
 116	u32	xRR;		/* Receive Register0 */
 117	u32	xSR[IMX_MU_xSR_MAX];	/* Status Registers */
 118	u32	xCR[IMX_MU_xCR_MAX];	/* Control Registers */
 119};
 120
 121#define IMX_MU_xSR_GIPn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
 122#define IMX_MU_xSR_RFn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
 123#define IMX_MU_xSR_TEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
 124
 125/* General Purpose Interrupt Enable */
 126#define IMX_MU_xCR_GIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 - (x))))
 127/* Receive Interrupt Enable */
 128#define IMX_MU_xCR_RIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
 129/* Transmit Interrupt Enable */
 130#define IMX_MU_xCR_TIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 - (x))))
 131/* General Purpose Interrupt Request */
 132#define IMX_MU_xCR_GIRn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(16 + (3 - (x))))
 133/* MU reset */
 134#define IMX_MU_xCR_RST(type)	(type & IMX_MU_V2 ? BIT(0) : BIT(5))
 135#define IMX_MU_xSR_RST(type)	(type & IMX_MU_V2 ? BIT(0) : BIT(7))
 136
 137
 138static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
 139{
 140	return container_of(mbox, struct imx_mu_priv, mbox);
 141}
 142
 143static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
 144{
 145	iowrite32(val, priv->base + offs);
 146}
 147
 148static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
 149{
 150	return ioread32(priv->base + offs);
 151}
 152
 153static int imx_mu_tx_waiting_write(struct imx_mu_priv *priv, u32 val, u32 idx)
 154{
 155	u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_TX_TOUT;
 156	u32 status;
 157	u32 can_write;
 158
 159	dev_dbg(priv->dev, "Trying to write %.8x to idx %d\n", val, idx);
 160
 161	do {
 162		status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
 163		can_write = status & IMX_MU_xSR_TEn(priv->dcfg->type, idx % 4);
 164	} while (!can_write && time_is_after_jiffies64(timeout_time));
 165
 166	if (!can_write) {
 167		dev_err(priv->dev, "timeout trying to write %.8x at %d(%.8x)\n",
 168			val, idx, status);
 169		return -ETIME;
 170	}
 171
 172	imx_mu_write(priv, val, priv->dcfg->xTR + (idx % 4) * 4);
 173
 174	return 0;
 175}
 176
 177static int imx_mu_rx_waiting_read(struct imx_mu_priv *priv, u32 *val, u32 idx)
 178{
 179	u64 timeout_time = get_jiffies_64() + IMX_MU_SECO_RX_TOUT;
 180	u32 status;
 181	u32 can_read;
 182
 183	dev_dbg(priv->dev, "Trying to read from idx %d\n", idx);
 184
 185	do {
 186		status = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
 187		can_read = status & IMX_MU_xSR_RFn(priv->dcfg->type, idx % 4);
 188	} while (!can_read && time_is_after_jiffies64(timeout_time));
 189
 190	if (!can_read) {
 191		dev_err(priv->dev, "timeout trying to read idx %d (%.8x)\n",
 192			idx, status);
 193		return -ETIME;
 194	}
 195
 196	*val = imx_mu_read(priv, priv->dcfg->xRR + (idx % 4) * 4);
 197	dev_dbg(priv->dev, "Read %.8x\n", *val);
 198
 199	return 0;
 200}
 201
 202static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, enum imx_mu_xcr type, u32 set, u32 clr)
 203{
 204	unsigned long flags;
 205	u32 val;
 206
 207	spin_lock_irqsave(&priv->xcr_lock, flags);
 208	val = imx_mu_read(priv, priv->dcfg->xCR[type]);
 209	val &= ~clr;
 210	val |= set;
 211	imx_mu_write(priv, val, priv->dcfg->xCR[type]);
 212	spin_unlock_irqrestore(&priv->xcr_lock, flags);
 213
 214	return val;
 215}
 216
 217static int imx_mu_generic_tx(struct imx_mu_priv *priv,
 218			     struct imx_mu_con_priv *cp,
 219			     void *data)
 220{
 221	u32 *arg = data;
 222
 223	switch (cp->type) {
 224	case IMX_MU_TYPE_TX:
 225		imx_mu_write(priv, *arg, priv->dcfg->xTR + cp->idx * 4);
 226		imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
 227		break;
 228	case IMX_MU_TYPE_TXDB:
 229		imx_mu_xcr_rmw(priv, IMX_MU_GCR, IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
 230		tasklet_schedule(&cp->txdb_tasklet);
 231		break;
 232	case IMX_MU_TYPE_TXDB_V2:
 233		imx_mu_xcr_rmw(priv, IMX_MU_GCR, IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
 234		break;
 235	default:
 236		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
 237		return -EINVAL;
 238	}
 239
 240	return 0;
 241}
 242
 243static int imx_mu_generic_rx(struct imx_mu_priv *priv,
 244			     struct imx_mu_con_priv *cp)
 245{
 246	u32 dat;
 247
 248	dat = imx_mu_read(priv, priv->dcfg->xRR + (cp->idx) * 4);
 249	mbox_chan_received_data(cp->chan, (void *)&dat);
 250
 251	return 0;
 252}
 253
 254static int imx_mu_generic_rxdb(struct imx_mu_priv *priv,
 255			       struct imx_mu_con_priv *cp)
 256{
 257	imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
 258		     priv->dcfg->xSR[IMX_MU_GSR]);
 259	mbox_chan_received_data(cp->chan, NULL);
 260
 261	return 0;
 262}
 263
 264static int imx_mu_specific_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data)
 265{
 
 266	u32 *arg = data;
 267	int i, ret;
 268	u32 xsr;
 269	u32 size, max_size, num_tr;
 270
 271	if (priv->dcfg->type & IMX_MU_V2_S4) {
 272		size = ((struct imx_s4_rpc_msg_max *)data)->hdr.size;
 273		max_size = sizeof(struct imx_s4_rpc_msg_max);
 274		num_tr = 8;
 275	} else {
 276		size = ((struct imx_sc_rpc_msg_max *)data)->hdr.size;
 277		max_size = sizeof(struct imx_sc_rpc_msg_max);
 278		num_tr = 4;
 279	}
 280
 281	switch (cp->type) {
 282	case IMX_MU_TYPE_TX:
 283		/*
 284		 * msg->hdr.size specifies the number of u32 words while
 285		 * sizeof yields bytes.
 286		 */
 287
 288		if (size > max_size / 4) {
 289			/*
 290			 * The real message size can be different to
 291			 * struct imx_sc_rpc_msg_max/imx_s4_rpc_msg_max size
 292			 */
 293			dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on TX; got: %i bytes\n", max_size, size << 2);
 294			return -EINVAL;
 295		}
 296
 297		for (i = 0; i < num_tr && i < size; i++)
 298			imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
 299		for (; i < size; i++) {
 300			ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_TSR],
 301						 xsr,
 302						 xsr & IMX_MU_xSR_TEn(priv->dcfg->type, i % num_tr),
 303						 0, 5 * USEC_PER_SEC);
 304			if (ret) {
 305				dev_err(priv->dev, "Send data index: %d timeout\n", i);
 306				return ret;
 307			}
 308			imx_mu_write(priv, *arg++, priv->dcfg->xTR + (i % num_tr) * 4);
 309		}
 310
 311		imx_mu_xcr_rmw(priv, IMX_MU_TCR, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx), 0);
 312		break;
 313	default:
 314		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
 315		return -EINVAL;
 316	}
 317
 318	return 0;
 319}
 320
 321static int imx_mu_specific_rx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
 
 322{
 323	u32 *data;
 
 324	int i, ret;
 325	u32 xsr;
 326	u32 size, max_size;
 327
 328	data = (u32 *)priv->msg;
 329
 330	imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, 0));
 331	*data++ = imx_mu_read(priv, priv->dcfg->xRR);
 332
 333	if (priv->dcfg->type & IMX_MU_V2_S4) {
 334		size = ((struct imx_s4_rpc_msg_max *)priv->msg)->hdr.size;
 335		max_size = sizeof(struct imx_s4_rpc_msg_max);
 336	} else {
 337		size = ((struct imx_sc_rpc_msg_max *)priv->msg)->hdr.size;
 338		max_size = sizeof(struct imx_sc_rpc_msg_max);
 339	}
 340
 341	if (size > max_size / 4) {
 342		dev_err(priv->dev, "Maximal message size (%u bytes) exceeded on RX; got: %i bytes\n", max_size, size << 2);
 343		return -EINVAL;
 344	}
 345
 346	for (i = 1; i < size; i++) {
 347		ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_RSR], xsr,
 348					 xsr & IMX_MU_xSR_RFn(priv->dcfg->type, i % 4), 0,
 349					 5 * USEC_PER_SEC);
 350		if (ret) {
 351			dev_err(priv->dev, "timeout read idx %d\n", i);
 352			return ret;
 353		}
 354		*data++ = imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
 355	}
 356
 357	imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, 0), 0);
 358	mbox_chan_received_data(cp->chan, (void *)priv->msg);
 359
 360	return 0;
 361}
 362
 363static int imx_mu_seco_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp,
 364			  void *data)
 365{
 366	struct imx_sc_rpc_msg_max *msg = data;
 367	u32 *arg = data;
 368	u32 byte_size;
 369	int err;
 370	int i;
 371
 372	dev_dbg(priv->dev, "Sending message\n");
 373
 374	switch (cp->type) {
 375	case IMX_MU_TYPE_TXDB:
 376		byte_size = msg->hdr.size * sizeof(u32);
 377		if (byte_size > sizeof(*msg)) {
 378			/*
 379			 * The real message size can be different to
 380			 * struct imx_sc_rpc_msg_max size
 381			 */
 382			dev_err(priv->dev,
 383				"Exceed max msg size (%zu) on TX, got: %i\n",
 384				sizeof(*msg), byte_size);
 385			return -EINVAL;
 386		}
 387
 388		print_hex_dump_debug("from client ", DUMP_PREFIX_OFFSET, 4, 4,
 389				     data, byte_size, false);
 390
 391		/* Send first word */
 392		dev_dbg(priv->dev, "Sending header\n");
 393		imx_mu_write(priv, *arg++, priv->dcfg->xTR);
 394
 395		/* Send signaling */
 396		dev_dbg(priv->dev, "Sending signaling\n");
 397		imx_mu_xcr_rmw(priv, IMX_MU_GCR,
 398			       IMX_MU_xCR_GIRn(priv->dcfg->type, cp->idx), 0);
 399
 400		/* Send words to fill the mailbox */
 401		for (i = 1; i < 4 && i < msg->hdr.size; i++) {
 402			dev_dbg(priv->dev, "Sending word %d\n", i);
 403			imx_mu_write(priv, *arg++,
 404				     priv->dcfg->xTR + (i % 4) * 4);
 405		}
 406
 407		/* Send rest of message waiting for remote read */
 408		for (; i < msg->hdr.size; i++) {
 409			dev_dbg(priv->dev, "Sending word %d\n", i);
 410			err = imx_mu_tx_waiting_write(priv, *arg++, i);
 411			if (err) {
 412				dev_err(priv->dev, "Timeout tx %d\n", i);
 413				return err;
 414			}
 415		}
 416
 417		/* Simulate hack for mbox framework */
 418		tasklet_schedule(&cp->txdb_tasklet);
 419
 420		break;
 421	default:
 422		dev_warn_ratelimited(priv->dev,
 423				     "Send data on wrong channel type: %d\n",
 424				     cp->type);
 425		return -EINVAL;
 426	}
 427
 428	return 0;
 429}
 430
 431static int imx_mu_seco_rxdb(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp)
 432{
 433	struct imx_sc_rpc_msg_max msg;
 434	u32 *data = (u32 *)&msg;
 435	u32 byte_size;
 436	int err = 0;
 437	int i;
 438
 439	dev_dbg(priv->dev, "Receiving message\n");
 440
 441	/* Read header */
 442	dev_dbg(priv->dev, "Receiving header\n");
 443	*data++ = imx_mu_read(priv, priv->dcfg->xRR);
 444	byte_size = msg.hdr.size * sizeof(u32);
 445	if (byte_size > sizeof(msg)) {
 446		dev_err(priv->dev, "Exceed max msg size (%zu) on RX, got: %i\n",
 447			sizeof(msg), byte_size);
 448		err = -EINVAL;
 449		goto error;
 450	}
 451
 452	/* Read message waiting they are written */
 453	for (i = 1; i < msg.hdr.size; i++) {
 454		dev_dbg(priv->dev, "Receiving word %d\n", i);
 455		err = imx_mu_rx_waiting_read(priv, data++, i);
 456		if (err) {
 457			dev_err(priv->dev, "Timeout rx %d\n", i);
 458			goto error;
 459		}
 460	}
 461
 462	/* Clear GIP */
 463	imx_mu_write(priv, IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx),
 464		     priv->dcfg->xSR[IMX_MU_GSR]);
 465
 466	print_hex_dump_debug("to client ", DUMP_PREFIX_OFFSET, 4, 4,
 467			     &msg, byte_size, false);
 468
 469	/* send data to client */
 470	dev_dbg(priv->dev, "Sending message to client\n");
 471	mbox_chan_received_data(cp->chan, (void *)&msg);
 472
 473	goto exit;
 474
 475error:
 476	mbox_chan_received_data(cp->chan, ERR_PTR(err));
 477
 478exit:
 479	return err;
 480}
 481
 482static void imx_mu_txdb_tasklet(unsigned long data)
 483{
 484	struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
 485
 486	mbox_chan_txdone(cp->chan, 0);
 487}
 488
 489static irqreturn_t imx_mu_isr(int irq, void *p)
 490{
 491	struct mbox_chan *chan = p;
 492	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 493	struct imx_mu_con_priv *cp = chan->con_priv;
 494	u32 val, ctrl;
 495
 
 
 
 496	switch (cp->type) {
 497	case IMX_MU_TYPE_TX:
 498		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_TCR]);
 499		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_TSR]);
 500		val &= IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx) &
 501			(ctrl & IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
 502		break;
 503	case IMX_MU_TYPE_RX:
 504		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_RCR]);
 505		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_RSR]);
 506		val &= IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx) &
 507			(ctrl & IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
 508		break;
 509	case IMX_MU_TYPE_RXDB:
 510		ctrl = imx_mu_read(priv, priv->dcfg->xCR[IMX_MU_GIER]);
 511		val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_GSR]);
 512		val &= IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx) &
 513			(ctrl & IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
 514		break;
 515	case IMX_MU_TYPE_RST:
 516		return IRQ_NONE;
 517	default:
 518		dev_warn_ratelimited(priv->dev, "Unhandled channel type %d\n",
 519				     cp->type);
 520		return IRQ_NONE;
 521	}
 522
 523	if (!val)
 524		return IRQ_NONE;
 525
 526	if ((val == IMX_MU_xSR_TEn(priv->dcfg->type, cp->idx)) &&
 527	    (cp->type == IMX_MU_TYPE_TX)) {
 528		imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
 529		mbox_chan_txdone(chan, 0);
 530	} else if ((val == IMX_MU_xSR_RFn(priv->dcfg->type, cp->idx)) &&
 531		   (cp->type == IMX_MU_TYPE_RX)) {
 532		priv->dcfg->rx(priv, cp);
 533	} else if ((val == IMX_MU_xSR_GIPn(priv->dcfg->type, cp->idx)) &&
 534		   (cp->type == IMX_MU_TYPE_RXDB)) {
 535		priv->dcfg->rxdb(priv, cp);
 536	} else {
 537		dev_warn_ratelimited(priv->dev, "Not handled interrupt\n");
 538		return IRQ_NONE;
 539	}
 540
 541	if (priv->suspend)
 542		pm_system_wakeup();
 543
 544	return IRQ_HANDLED;
 545}
 546
 547static int imx_mu_send_data(struct mbox_chan *chan, void *data)
 548{
 549	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 550	struct imx_mu_con_priv *cp = chan->con_priv;
 551
 552	return priv->dcfg->tx(priv, cp, data);
 553}
 554
 555static int imx_mu_startup(struct mbox_chan *chan)
 556{
 557	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 558	struct imx_mu_con_priv *cp = chan->con_priv;
 559	unsigned long irq_flag = 0;
 560	int ret;
 561
 562	pm_runtime_get_sync(priv->dev);
 563	if (cp->type == IMX_MU_TYPE_TXDB_V2)
 564		return 0;
 565
 566	if (cp->type == IMX_MU_TYPE_TXDB) {
 567		/* Tx doorbell don't have ACK support */
 568		tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
 569			     (unsigned long)cp);
 570		return 0;
 571	}
 572
 573	/* IPC MU should be with IRQF_NO_SUSPEND set */
 574	if (!priv->dev->pm_domain)
 575		irq_flag |= IRQF_NO_SUSPEND;
 576
 577	if (!(priv->dcfg->type & IMX_MU_V2_IRQ))
 578		irq_flag |= IRQF_SHARED;
 579
 580	ret = request_irq(priv->irq[cp->type], imx_mu_isr, irq_flag, cp->irq_desc, chan);
 581	if (ret) {
 582		dev_err(priv->dev, "Unable to acquire IRQ %d\n", priv->irq[cp->type]);
 
 583		return ret;
 584	}
 585
 586	switch (cp->type) {
 587	case IMX_MU_TYPE_RX:
 588		imx_mu_xcr_rmw(priv, IMX_MU_RCR, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx), 0);
 589		break;
 590	case IMX_MU_TYPE_RXDB:
 591		imx_mu_xcr_rmw(priv, IMX_MU_GIER, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx), 0);
 592		break;
 593	default:
 594		break;
 595	}
 596
 597	return 0;
 598}
 599
 600static void imx_mu_shutdown(struct mbox_chan *chan)
 601{
 602	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 603	struct imx_mu_con_priv *cp = chan->con_priv;
 604	int ret;
 605	u32 sr;
 606
 607	if (cp->type == IMX_MU_TYPE_TXDB_V2) {
 608		pm_runtime_put_sync(priv->dev);
 609		return;
 610	}
 611
 612	if (cp->type == IMX_MU_TYPE_TXDB) {
 613		tasklet_kill(&cp->txdb_tasklet);
 614		pm_runtime_put_sync(priv->dev);
 615		return;
 616	}
 617
 618	switch (cp->type) {
 619	case IMX_MU_TYPE_TX:
 620		imx_mu_xcr_rmw(priv, IMX_MU_TCR, 0, IMX_MU_xCR_TIEn(priv->dcfg->type, cp->idx));
 621		break;
 622	case IMX_MU_TYPE_RX:
 623		imx_mu_xcr_rmw(priv, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(priv->dcfg->type, cp->idx));
 624		break;
 625	case IMX_MU_TYPE_RXDB:
 626		imx_mu_xcr_rmw(priv, IMX_MU_GIER, 0, IMX_MU_xCR_GIEn(priv->dcfg->type, cp->idx));
 627		break;
 628	case IMX_MU_TYPE_RST:
 629		imx_mu_xcr_rmw(priv, IMX_MU_CR, IMX_MU_xCR_RST(priv->dcfg->type), 0);
 630		ret = readl_poll_timeout(priv->base + priv->dcfg->xSR[IMX_MU_SR], sr,
 631					 !(sr & IMX_MU_xSR_RST(priv->dcfg->type)), 1, 5);
 632		if (ret)
 633			dev_warn(priv->dev, "RST channel timeout\n");
 634		break;
 635	default:
 636		break;
 637	}
 638
 639	free_irq(priv->irq[cp->type], chan);
 640	pm_runtime_put_sync(priv->dev);
 641}
 642
 643static const struct mbox_chan_ops imx_mu_ops = {
 644	.send_data = imx_mu_send_data,
 645	.startup = imx_mu_startup,
 646	.shutdown = imx_mu_shutdown,
 647};
 648
 649static struct mbox_chan *imx_mu_specific_xlate(struct mbox_controller *mbox,
 650					       const struct of_phandle_args *sp)
 651{
 652	u32 type, idx, chan;
 653
 654	if (sp->args_count != 2) {
 655		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
 656		return ERR_PTR(-EINVAL);
 657	}
 658
 659	type = sp->args[0]; /* channel type */
 660	idx = sp->args[1]; /* index */
 661
 662	switch (type) {
 663	case IMX_MU_TYPE_TX:
 664	case IMX_MU_TYPE_RX:
 665		if (idx != 0)
 666			dev_err(mbox->dev, "Invalid chan idx: %d\n", idx);
 667		chan = type;
 668		break;
 669	case IMX_MU_TYPE_RXDB:
 670		chan = 2 + idx;
 671		break;
 672	default:
 673		dev_err(mbox->dev, "Invalid chan type: %d\n", type);
 674		return ERR_PTR(-EINVAL);
 675	}
 676
 677	if (chan >= mbox->num_chans) {
 678		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
 679		return ERR_PTR(-EINVAL);
 680	}
 681
 682	return &mbox->chans[chan];
 683}
 684
 685static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox,
 686				       const struct of_phandle_args *sp)
 687{
 688	struct mbox_chan *p_chan;
 689	u32 type, idx, chan;
 690
 691	if (sp->args_count != 2) {
 692		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
 693		return ERR_PTR(-EINVAL);
 694	}
 695
 696	type = sp->args[0]; /* channel type */
 697	idx = sp->args[1]; /* index */
 698
 699	/* RST only supports 1 channel */
 700	if ((type == IMX_MU_TYPE_RST) && idx) {
 701		dev_err(mbox->dev, "Invalid RST channel %d\n", idx);
 702		return ERR_PTR(-EINVAL);
 703	}
 704
 705	chan = type * 4 + idx;
 
 706	if (chan >= mbox->num_chans) {
 707		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
 708		return ERR_PTR(-EINVAL);
 709	}
 710
 711	p_chan = &mbox->chans[chan];
 712
 713	if (type == IMX_MU_TYPE_TXDB_V2)
 714		p_chan->txdone_method = TXDONE_BY_ACK;
 715
 716	return p_chan;
 717}
 718
 719static struct mbox_chan *imx_mu_seco_xlate(struct mbox_controller *mbox,
 720					   const struct of_phandle_args *sp)
 721{
 722	u32 type;
 723
 724	if (sp->args_count < 1) {
 725		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
 726		return ERR_PTR(-EINVAL);
 727	}
 728
 729	type = sp->args[0]; /* channel type */
 730
 731	/* Only supports TXDB and RXDB */
 732	if (type == IMX_MU_TYPE_TX || type == IMX_MU_TYPE_RX) {
 733		dev_err(mbox->dev, "Invalid type: %d\n", type);
 734		return ERR_PTR(-EINVAL);
 735	}
 736
 737	return imx_mu_xlate(mbox, sp);
 738}
 739
 740static void imx_mu_init_generic(struct imx_mu_priv *priv)
 741{
 742	unsigned int i;
 743	unsigned int val;
 744
 745	for (i = 0; i < IMX_MU_CHANS; i++) {
 746		struct imx_mu_con_priv *cp = &priv->con_priv[i];
 747
 748		cp->idx = i % 4;
 749		cp->type = i >> 2;
 750		cp->chan = &priv->mbox_chans[i];
 751		priv->mbox_chans[i].con_priv = cp;
 752		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
 753			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
 754	}
 755
 756	priv->mbox.num_chans = IMX_MU_CHANS;
 757	priv->mbox.of_xlate = imx_mu_xlate;
 758
 759	if (priv->side_b)
 760		return;
 761
 762	/* Set default MU configuration */
 763	for (i = 0; i < IMX_MU_xCR_MAX; i++)
 764		imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
 765
 766	/* Clear any pending GIP */
 767	val = imx_mu_read(priv, priv->dcfg->xSR[IMX_MU_GSR]);
 768	imx_mu_write(priv, val, priv->dcfg->xSR[IMX_MU_GSR]);
 769
 770	/* Clear any pending RSR */
 771	for (i = 0; i < IMX_MU_NUM_RR; i++)
 772		imx_mu_read(priv, priv->dcfg->xRR + (i % 4) * 4);
 773}
 774
 775static void imx_mu_init_specific(struct imx_mu_priv *priv)
 776{
 777	unsigned int i;
 778	int num_chans = priv->dcfg->type & IMX_MU_V2_S4 ? IMX_MU_S4_CHANS : IMX_MU_SCU_CHANS;
 779
 780	for (i = 0; i < num_chans; i++) {
 781		struct imx_mu_con_priv *cp = &priv->con_priv[i];
 782
 783		cp->idx = i < 2 ? 0 : i - 2;
 784		cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB;
 785		cp->chan = &priv->mbox_chans[i];
 786		priv->mbox_chans[i].con_priv = cp;
 787		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
 788			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
 789	}
 790
 791	priv->mbox.num_chans = num_chans;
 792	priv->mbox.of_xlate = imx_mu_specific_xlate;
 793
 794	/* Set default MU configuration */
 795	for (i = 0; i < IMX_MU_xCR_MAX; i++)
 796		imx_mu_write(priv, 0, priv->dcfg->xCR[i]);
 797}
 798
 799static void imx_mu_init_seco(struct imx_mu_priv *priv)
 800{
 801	imx_mu_init_generic(priv);
 802	priv->mbox.of_xlate = imx_mu_seco_xlate;
 803}
 804
 805static int imx_mu_probe(struct platform_device *pdev)
 806{
 807	struct device *dev = &pdev->dev;
 808	struct device_node *np = dev->of_node;
 809	struct imx_mu_priv *priv;
 810	const struct imx_mu_dcfg *dcfg;
 811	int i, ret;
 812	u32 size;
 813
 814	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 815	if (!priv)
 816		return -ENOMEM;
 817
 818	priv->dev = dev;
 819
 820	priv->base = devm_platform_ioremap_resource(pdev, 0);
 821	if (IS_ERR(priv->base))
 822		return PTR_ERR(priv->base);
 823
 
 
 
 
 824	dcfg = of_device_get_match_data(dev);
 825	if (!dcfg)
 826		return -EINVAL;
 827	priv->dcfg = dcfg;
 828	if (priv->dcfg->type & IMX_MU_V2_IRQ) {
 829		priv->irq[IMX_MU_TYPE_TX] = platform_get_irq_byname(pdev, "tx");
 830		if (priv->irq[IMX_MU_TYPE_TX] < 0)
 831			return priv->irq[IMX_MU_TYPE_TX];
 832		priv->irq[IMX_MU_TYPE_RX] = platform_get_irq_byname(pdev, "rx");
 833		if (priv->irq[IMX_MU_TYPE_RX] < 0)
 834			return priv->irq[IMX_MU_TYPE_RX];
 835	} else {
 836		ret = platform_get_irq(pdev, 0);
 837		if (ret < 0)
 838			return ret;
 839
 840		for (i = 0; i < IMX_MU_CHANS; i++)
 841			priv->irq[i] = ret;
 842	}
 843
 844	if (priv->dcfg->type & IMX_MU_V2_S4)
 845		size = sizeof(struct imx_s4_rpc_msg_max);
 846	else
 847		size = sizeof(struct imx_sc_rpc_msg_max);
 848
 849	priv->msg = devm_kzalloc(dev, size, GFP_KERNEL);
 850	if (!priv->msg)
 851		return -ENOMEM;
 852
 853	priv->clk = devm_clk_get(dev, NULL);
 854	if (IS_ERR(priv->clk)) {
 855		if (PTR_ERR(priv->clk) != -ENOENT)
 856			return PTR_ERR(priv->clk);
 857
 858		priv->clk = NULL;
 859	}
 860
 861	ret = clk_prepare_enable(priv->clk);
 862	if (ret) {
 863		dev_err(dev, "Failed to enable clock\n");
 864		return ret;
 865	}
 866
 867	priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
 868
 869	priv->dcfg->init(priv);
 870
 871	spin_lock_init(&priv->xcr_lock);
 872
 873	priv->mbox.dev = dev;
 874	priv->mbox.ops = &imx_mu_ops;
 875	priv->mbox.chans = priv->mbox_chans;
 876	priv->mbox.txdone_irq = true;
 877
 878	platform_set_drvdata(pdev, priv);
 879
 880	ret = devm_mbox_controller_register(dev, &priv->mbox);
 881	if (ret) {
 882		clk_disable_unprepare(priv->clk);
 883		return ret;
 884	}
 885
 886	pm_runtime_enable(dev);
 887
 888	ret = pm_runtime_resume_and_get(dev);
 889	if (ret < 0)
 
 890		goto disable_runtime_pm;
 
 891
 892	ret = pm_runtime_put_sync(dev);
 893	if (ret < 0)
 894		goto disable_runtime_pm;
 895
 896	clk_disable_unprepare(priv->clk);
 897
 898	return 0;
 899
 900disable_runtime_pm:
 901	pm_runtime_disable(dev);
 902	clk_disable_unprepare(priv->clk);
 903	return ret;
 904}
 905
 906static void imx_mu_remove(struct platform_device *pdev)
 907{
 908	struct imx_mu_priv *priv = platform_get_drvdata(pdev);
 909
 910	pm_runtime_disable(priv->dev);
 
 
 911}
 912
 913static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
 914	.tx	= imx_mu_generic_tx,
 915	.rx	= imx_mu_generic_rx,
 916	.rxdb	= imx_mu_generic_rxdb,
 917	.init	= imx_mu_init_generic,
 918	.xTR	= 0x0,
 919	.xRR	= 0x10,
 920	.xSR	= {0x20, 0x20, 0x20, 0x20},
 921	.xCR	= {0x24, 0x24, 0x24, 0x24, 0x24},
 922};
 923
 924static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
 925	.tx	= imx_mu_generic_tx,
 926	.rx	= imx_mu_generic_rx,
 927	.rxdb	= imx_mu_generic_rxdb,
 928	.init	= imx_mu_init_generic,
 929	.xTR	= 0x20,
 930	.xRR	= 0x40,
 931	.xSR	= {0x60, 0x60, 0x60, 0x60},
 932	.xCR	= {0x64, 0x64, 0x64, 0x64, 0x64},
 933};
 934
 935static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp = {
 936	.tx	= imx_mu_generic_tx,
 937	.rx	= imx_mu_generic_rx,
 938	.rxdb	= imx_mu_generic_rxdb,
 939	.init	= imx_mu_init_generic,
 940	.type	= IMX_MU_V2,
 941	.xTR	= 0x200,
 942	.xRR	= 0x280,
 943	.xSR	= {0xC, 0x118, 0x124, 0x12C},
 944	.xCR	= {0x8, 0x110, 0x114, 0x120, 0x128},
 945};
 946
 947static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp_s4 = {
 948	.tx	= imx_mu_specific_tx,
 949	.rx	= imx_mu_specific_rx,
 950	.init	= imx_mu_init_specific,
 951	.type	= IMX_MU_V2 | IMX_MU_V2_S4,
 952	.xTR	= 0x200,
 953	.xRR	= 0x280,
 954	.xSR	= {0xC, 0x118, 0x124, 0x12C},
 955	.xCR	= {0x8, 0x110, 0x114, 0x120, 0x128},
 956};
 957
 958static const struct imx_mu_dcfg imx_mu_cfg_imx93_s4 = {
 959	.tx	= imx_mu_specific_tx,
 960	.rx	= imx_mu_specific_rx,
 961	.init	= imx_mu_init_specific,
 962	.type	= IMX_MU_V2 | IMX_MU_V2_S4 | IMX_MU_V2_IRQ,
 963	.xTR	= 0x200,
 964	.xRR	= 0x280,
 965	.xSR	= {0xC, 0x118, 0x124, 0x12C},
 966	.xCR	= {0x8, 0x110, 0x114, 0x120, 0x128},
 967};
 968
 969static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = {
 970	.tx	= imx_mu_specific_tx,
 971	.rx	= imx_mu_specific_rx,
 972	.init	= imx_mu_init_specific,
 973	.rxdb	= imx_mu_generic_rxdb,
 974	.xTR	= 0x0,
 975	.xRR	= 0x10,
 976	.xSR	= {0x20, 0x20, 0x20, 0x20},
 977	.xCR	= {0x24, 0x24, 0x24, 0x24, 0x24},
 978};
 979
 980static const struct imx_mu_dcfg imx_mu_cfg_imx8_seco = {
 981	.tx	= imx_mu_seco_tx,
 982	.rx	= imx_mu_generic_rx,
 983	.rxdb	= imx_mu_seco_rxdb,
 984	.init	= imx_mu_init_seco,
 985	.xTR	= 0x0,
 986	.xRR	= 0x10,
 987	.xSR	= {0x20, 0x20, 0x20, 0x20},
 988	.xCR	= {0x24, 0x24, 0x24, 0x24, 0x24},
 989};
 990
 991static const struct of_device_id imx_mu_dt_ids[] = {
 992	{ .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },
 993	{ .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx },
 994	{ .compatible = "fsl,imx8ulp-mu", .data = &imx_mu_cfg_imx8ulp },
 995	{ .compatible = "fsl,imx8ulp-mu-s4", .data = &imx_mu_cfg_imx8ulp_s4 },
 996	{ .compatible = "fsl,imx93-mu-s4", .data = &imx_mu_cfg_imx93_s4 },
 997	{ .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu },
 998	{ .compatible = "fsl,imx8-mu-seco", .data = &imx_mu_cfg_imx8_seco },
 999	{ },
1000};
1001MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
1002
1003static int __maybe_unused imx_mu_suspend_noirq(struct device *dev)
1004{
1005	struct imx_mu_priv *priv = dev_get_drvdata(dev);
1006	int i;
1007
1008	if (!priv->clk) {
1009		for (i = 0; i < IMX_MU_xCR_MAX; i++)
1010			priv->xcr[i] = imx_mu_read(priv, priv->dcfg->xCR[i]);
1011	}
1012
1013	priv->suspend = true;
 
1014
1015	return 0;
1016}
1017
1018static int __maybe_unused imx_mu_resume_noirq(struct device *dev)
1019{
1020	struct imx_mu_priv *priv = dev_get_drvdata(dev);
1021	int i;
1022
1023	/*
1024	 * ONLY restore MU when context lost, the TIE could
1025	 * be set during noirq resume as there is MU data
1026	 * communication going on, and restore the saved
1027	 * value will overwrite the TIE and cause MU data
1028	 * send failed, may lead to system freeze. This issue
1029	 * is observed by testing freeze mode suspend.
1030	 */
1031	if (!priv->clk && !imx_mu_read(priv, priv->dcfg->xCR[0])) {
1032		for (i = 0; i < IMX_MU_xCR_MAX; i++)
1033			imx_mu_write(priv, priv->xcr[i], priv->dcfg->xCR[i]);
1034	}
1035
1036	priv->suspend = false;
1037
1038	return 0;
1039}
1040
1041static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
1042{
1043	struct imx_mu_priv *priv = dev_get_drvdata(dev);
1044
1045	clk_disable_unprepare(priv->clk);
1046
1047	return 0;
1048}
1049
1050static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
1051{
1052	struct imx_mu_priv *priv = dev_get_drvdata(dev);
1053	int ret;
1054
1055	ret = clk_prepare_enable(priv->clk);
1056	if (ret)
1057		dev_err(dev, "failed to enable clock\n");
1058
1059	return ret;
1060}
1061
1062static const struct dev_pm_ops imx_mu_pm_ops = {
1063	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq,
1064				      imx_mu_resume_noirq)
1065	SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
1066			   imx_mu_runtime_resume, NULL)
1067};
1068
1069static struct platform_driver imx_mu_driver = {
1070	.probe		= imx_mu_probe,
1071	.remove_new	= imx_mu_remove,
1072	.driver = {
1073		.name	= "imx_mu",
1074		.of_match_table = imx_mu_dt_ids,
1075		.pm = &imx_mu_pm_ops,
1076	},
1077};
1078module_platform_driver(imx_mu_driver);
1079
1080MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
1081MODULE_DESCRIPTION("Message Unit driver for i.MX");
1082MODULE_LICENSE("GPL v2");
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de>
 
  4 */
  5
  6#include <linux/clk.h>
  7#include <linux/firmware/imx/ipc.h>
 
  8#include <linux/interrupt.h>
  9#include <linux/io.h>
 10#include <linux/iopoll.h>
 
 11#include <linux/kernel.h>
 12#include <linux/mailbox_controller.h>
 13#include <linux/module.h>
 14#include <linux/of_device.h>
 
 15#include <linux/pm_runtime.h>
 
 16#include <linux/slab.h>
 17
 18#define IMX_MU_xSR_GIPn(x)	BIT(28 + (3 - (x)))
 19#define IMX_MU_xSR_RFn(x)	BIT(24 + (3 - (x)))
 20#define IMX_MU_xSR_TEn(x)	BIT(20 + (3 - (x)))
 21#define IMX_MU_xSR_BRDIP	BIT(9)
 22
 23/* General Purpose Interrupt Enable */
 24#define IMX_MU_xCR_GIEn(x)	BIT(28 + (3 - (x)))
 25/* Receive Interrupt Enable */
 26#define IMX_MU_xCR_RIEn(x)	BIT(24 + (3 - (x)))
 27/* Transmit Interrupt Enable */
 28#define IMX_MU_xCR_TIEn(x)	BIT(20 + (3 - (x)))
 29/* General Purpose Interrupt Request */
 30#define IMX_MU_xCR_GIRn(x)	BIT(16 + (3 - (x)))
 31
 32#define IMX_MU_CHANS		16
 33/* TX0/RX0/RXDB[0-3] */
 34#define IMX_MU_SCU_CHANS	6
 
 
 35#define IMX_MU_CHAN_NAME_SIZE	20
 36
 
 
 
 
 
 
 37enum imx_mu_chan_type {
 38	IMX_MU_TYPE_TX,		/* Tx */
 39	IMX_MU_TYPE_RX,		/* Rx */
 40	IMX_MU_TYPE_TXDB,	/* Tx doorbell */
 41	IMX_MU_TYPE_RXDB,	/* Rx doorbell */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 42};
 43
 44struct imx_sc_rpc_msg_max {
 45	struct imx_sc_rpc_msg hdr;
 46	u32 data[7];
 
 
 
 
 
 47};
 48
 49struct imx_mu_con_priv {
 50	unsigned int		idx;
 51	char			irq_desc[IMX_MU_CHAN_NAME_SIZE];
 52	enum imx_mu_chan_type	type;
 53	struct mbox_chan	*chan;
 54	struct tasklet_struct	txdb_tasklet;
 55};
 56
 57struct imx_mu_priv {
 58	struct device		*dev;
 59	void __iomem		*base;
 
 60	spinlock_t		xcr_lock; /* control register lock */
 61
 62	struct mbox_controller	mbox;
 63	struct mbox_chan	mbox_chans[IMX_MU_CHANS];
 64
 65	struct imx_mu_con_priv  con_priv[IMX_MU_CHANS];
 66	const struct imx_mu_dcfg	*dcfg;
 67	struct clk		*clk;
 68	int			irq;
 
 69
 70	u32 xcr;
 71
 72	bool			side_b;
 73};
 74
 
 
 
 
 
 
 
 75struct imx_mu_dcfg {
 76	int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
 77	int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
 
 78	void (*init)(struct imx_mu_priv *priv);
 79	u32	xTR[4];		/* Transmit Registers */
 80	u32	xRR[4];		/* Receive Registers */
 81	u32	xSR;		/* Status Register */
 82	u32	xCR;		/* Control Register */
 
 83};
 84
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 85static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
 86{
 87	return container_of(mbox, struct imx_mu_priv, mbox);
 88}
 89
 90static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
 91{
 92	iowrite32(val, priv->base + offs);
 93}
 94
 95static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
 96{
 97	return ioread32(priv->base + offs);
 98}
 99
100static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, u32 set, u32 clr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
101{
102	unsigned long flags;
103	u32 val;
104
105	spin_lock_irqsave(&priv->xcr_lock, flags);
106	val = imx_mu_read(priv, priv->dcfg->xCR);
107	val &= ~clr;
108	val |= set;
109	imx_mu_write(priv, val, priv->dcfg->xCR);
110	spin_unlock_irqrestore(&priv->xcr_lock, flags);
111
112	return val;
113}
114
115static int imx_mu_generic_tx(struct imx_mu_priv *priv,
116			     struct imx_mu_con_priv *cp,
117			     void *data)
118{
119	u32 *arg = data;
120
121	switch (cp->type) {
122	case IMX_MU_TYPE_TX:
123		imx_mu_write(priv, *arg, priv->dcfg->xTR[cp->idx]);
124		imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
125		break;
126	case IMX_MU_TYPE_TXDB:
127		imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIRn(cp->idx), 0);
128		tasklet_schedule(&cp->txdb_tasklet);
129		break;
 
 
 
130	default:
131		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
132		return -EINVAL;
133	}
134
135	return 0;
136}
137
138static int imx_mu_generic_rx(struct imx_mu_priv *priv,
139			     struct imx_mu_con_priv *cp)
140{
141	u32 dat;
142
143	dat = imx_mu_read(priv, priv->dcfg->xRR[cp->idx]);
144	mbox_chan_received_data(cp->chan, (void *)&dat);
145
146	return 0;
147}
148
149static int imx_mu_scu_tx(struct imx_mu_priv *priv,
150			 struct imx_mu_con_priv *cp,
151			 void *data)
 
 
 
 
 
 
 
 
152{
153	struct imx_sc_rpc_msg_max *msg = data;
154	u32 *arg = data;
155	int i, ret;
156	u32 xsr;
 
 
 
 
 
 
 
 
 
 
 
157
158	switch (cp->type) {
159	case IMX_MU_TYPE_TX:
160		/*
161		 * msg->hdr.size specifies the number of u32 words while
162		 * sizeof yields bytes.
163		 */
164
165		if (msg->hdr.size > sizeof(*msg) / 4) {
166			/*
167			 * The real message size can be different to
168			 * struct imx_sc_rpc_msg_max size
169			 */
170			dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on TX; got: %i bytes\n", sizeof(*msg), msg->hdr.size << 2);
171			return -EINVAL;
172		}
173
174		for (i = 0; i < 4 && i < msg->hdr.size; i++)
175			imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]);
176		for (; i < msg->hdr.size; i++) {
177			ret = readl_poll_timeout(priv->base + priv->dcfg->xSR,
178						 xsr,
179						 xsr & IMX_MU_xSR_TEn(i % 4),
180						 0, 100);
181			if (ret) {
182				dev_err(priv->dev, "Send data index: %d timeout\n", i);
183				return ret;
184			}
185			imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]);
186		}
187
188		imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
189		break;
190	default:
191		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
192		return -EINVAL;
193	}
194
195	return 0;
196}
197
198static int imx_mu_scu_rx(struct imx_mu_priv *priv,
199			 struct imx_mu_con_priv *cp)
200{
201	struct imx_sc_rpc_msg_max msg;
202	u32 *data = (u32 *)&msg;
203	int i, ret;
204	u32 xsr;
 
 
 
205
206	imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(0));
207	*data++ = imx_mu_read(priv, priv->dcfg->xRR[0]);
208
209	if (msg.hdr.size > sizeof(msg) / 4) {
210		dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on RX; got: %i bytes\n", sizeof(msg), msg.hdr.size << 2);
 
 
 
 
 
 
 
 
211		return -EINVAL;
212	}
213
214	for (i = 1; i < msg.hdr.size; i++) {
215		ret = readl_poll_timeout(priv->base + priv->dcfg->xSR, xsr,
216					 xsr & IMX_MU_xSR_RFn(i % 4), 0, 100);
 
217		if (ret) {
218			dev_err(priv->dev, "timeout read idx %d\n", i);
219			return ret;
220		}
221		*data++ = imx_mu_read(priv, priv->dcfg->xRR[i % 4]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
222	}
223
224	imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(0), 0);
 
 
 
 
 
 
 
 
225	mbox_chan_received_data(cp->chan, (void *)&msg);
226
227	return 0;
 
 
 
 
 
 
228}
229
230static void imx_mu_txdb_tasklet(unsigned long data)
231{
232	struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
233
234	mbox_chan_txdone(cp->chan, 0);
235}
236
237static irqreturn_t imx_mu_isr(int irq, void *p)
238{
239	struct mbox_chan *chan = p;
240	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
241	struct imx_mu_con_priv *cp = chan->con_priv;
242	u32 val, ctrl;
243
244	ctrl = imx_mu_read(priv, priv->dcfg->xCR);
245	val = imx_mu_read(priv, priv->dcfg->xSR);
246
247	switch (cp->type) {
248	case IMX_MU_TYPE_TX:
249		val &= IMX_MU_xSR_TEn(cp->idx) &
250			(ctrl & IMX_MU_xCR_TIEn(cp->idx));
 
 
251		break;
252	case IMX_MU_TYPE_RX:
253		val &= IMX_MU_xSR_RFn(cp->idx) &
254			(ctrl & IMX_MU_xCR_RIEn(cp->idx));
 
 
255		break;
256	case IMX_MU_TYPE_RXDB:
257		val &= IMX_MU_xSR_GIPn(cp->idx) &
258			(ctrl & IMX_MU_xCR_GIEn(cp->idx));
 
 
259		break;
 
 
260	default:
261		break;
 
 
262	}
263
264	if (!val)
265		return IRQ_NONE;
266
267	if (val == IMX_MU_xSR_TEn(cp->idx)) {
268		imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx));
 
269		mbox_chan_txdone(chan, 0);
270	} else if (val == IMX_MU_xSR_RFn(cp->idx)) {
 
271		priv->dcfg->rx(priv, cp);
272	} else if (val == IMX_MU_xSR_GIPn(cp->idx)) {
273		imx_mu_write(priv, IMX_MU_xSR_GIPn(cp->idx), priv->dcfg->xSR);
274		mbox_chan_received_data(chan, NULL);
275	} else {
276		dev_warn_ratelimited(priv->dev, "Not handled interrupt\n");
277		return IRQ_NONE;
278	}
279
 
 
 
280	return IRQ_HANDLED;
281}
282
283static int imx_mu_send_data(struct mbox_chan *chan, void *data)
284{
285	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
286	struct imx_mu_con_priv *cp = chan->con_priv;
287
288	return priv->dcfg->tx(priv, cp, data);
289}
290
291static int imx_mu_startup(struct mbox_chan *chan)
292{
293	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
294	struct imx_mu_con_priv *cp = chan->con_priv;
295	unsigned long irq_flag = IRQF_SHARED;
296	int ret;
297
298	pm_runtime_get_sync(priv->dev);
 
 
 
299	if (cp->type == IMX_MU_TYPE_TXDB) {
300		/* Tx doorbell don't have ACK support */
301		tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
302			     (unsigned long)cp);
303		return 0;
304	}
305
306	/* IPC MU should be with IRQF_NO_SUSPEND set */
307	if (!priv->dev->pm_domain)
308		irq_flag |= IRQF_NO_SUSPEND;
309
310	ret = request_irq(priv->irq, imx_mu_isr, irq_flag,
311			  cp->irq_desc, chan);
 
 
312	if (ret) {
313		dev_err(priv->dev,
314			"Unable to acquire IRQ %d\n", priv->irq);
315		return ret;
316	}
317
318	switch (cp->type) {
319	case IMX_MU_TYPE_RX:
320		imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(cp->idx), 0);
321		break;
322	case IMX_MU_TYPE_RXDB:
323		imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIEn(cp->idx), 0);
324		break;
325	default:
326		break;
327	}
328
329	return 0;
330}
331
332static void imx_mu_shutdown(struct mbox_chan *chan)
333{
334	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
335	struct imx_mu_con_priv *cp = chan->con_priv;
 
 
 
 
 
 
 
336
337	if (cp->type == IMX_MU_TYPE_TXDB) {
338		tasklet_kill(&cp->txdb_tasklet);
339		pm_runtime_put_sync(priv->dev);
340		return;
341	}
342
343	switch (cp->type) {
344	case IMX_MU_TYPE_TX:
345		imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx));
346		break;
347	case IMX_MU_TYPE_RX:
348		imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(cp->idx));
349		break;
350	case IMX_MU_TYPE_RXDB:
351		imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_GIEn(cp->idx));
 
 
 
 
 
 
 
352		break;
353	default:
354		break;
355	}
356
357	free_irq(priv->irq, chan);
358	pm_runtime_put_sync(priv->dev);
359}
360
361static const struct mbox_chan_ops imx_mu_ops = {
362	.send_data = imx_mu_send_data,
363	.startup = imx_mu_startup,
364	.shutdown = imx_mu_shutdown,
365};
366
367static struct mbox_chan *imx_mu_scu_xlate(struct mbox_controller *mbox,
368					  const struct of_phandle_args *sp)
369{
370	u32 type, idx, chan;
371
372	if (sp->args_count != 2) {
373		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
374		return ERR_PTR(-EINVAL);
375	}
376
377	type = sp->args[0]; /* channel type */
378	idx = sp->args[1]; /* index */
379
380	switch (type) {
381	case IMX_MU_TYPE_TX:
382	case IMX_MU_TYPE_RX:
383		if (idx != 0)
384			dev_err(mbox->dev, "Invalid chan idx: %d\n", idx);
385		chan = type;
386		break;
387	case IMX_MU_TYPE_RXDB:
388		chan = 2 + idx;
389		break;
390	default:
391		dev_err(mbox->dev, "Invalid chan type: %d\n", type);
392		return ERR_PTR(-EINVAL);
393	}
394
395	if (chan >= mbox->num_chans) {
396		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
397		return ERR_PTR(-EINVAL);
398	}
399
400	return &mbox->chans[chan];
401}
402
403static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox,
404				       const struct of_phandle_args *sp)
405{
 
406	u32 type, idx, chan;
407
408	if (sp->args_count != 2) {
409		dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
410		return ERR_PTR(-EINVAL);
411	}
412
413	type = sp->args[0]; /* channel type */
414	idx = sp->args[1]; /* index */
 
 
 
 
 
 
 
415	chan = type * 4 + idx;
416
417	if (chan >= mbox->num_chans) {
418		dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
419		return ERR_PTR(-EINVAL);
420	}
421
422	return &mbox->chans[chan];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
423}
424
425static void imx_mu_init_generic(struct imx_mu_priv *priv)
426{
427	unsigned int i;
 
428
429	for (i = 0; i < IMX_MU_CHANS; i++) {
430		struct imx_mu_con_priv *cp = &priv->con_priv[i];
431
432		cp->idx = i % 4;
433		cp->type = i >> 2;
434		cp->chan = &priv->mbox_chans[i];
435		priv->mbox_chans[i].con_priv = cp;
436		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
437			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
438	}
439
440	priv->mbox.num_chans = IMX_MU_CHANS;
441	priv->mbox.of_xlate = imx_mu_xlate;
442
443	if (priv->side_b)
444		return;
445
446	/* Set default MU configuration */
447	imx_mu_write(priv, 0, priv->dcfg->xCR);
 
 
 
 
 
 
 
 
 
448}
449
450static void imx_mu_init_scu(struct imx_mu_priv *priv)
451{
452	unsigned int i;
 
453
454	for (i = 0; i < IMX_MU_SCU_CHANS; i++) {
455		struct imx_mu_con_priv *cp = &priv->con_priv[i];
456
457		cp->idx = i < 2 ? 0 : i - 2;
458		cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB;
459		cp->chan = &priv->mbox_chans[i];
460		priv->mbox_chans[i].con_priv = cp;
461		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
462			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
463	}
464
465	priv->mbox.num_chans = IMX_MU_SCU_CHANS;
466	priv->mbox.of_xlate = imx_mu_scu_xlate;
467
468	/* Set default MU configuration */
469	imx_mu_write(priv, 0, priv->dcfg->xCR);
 
 
 
 
 
 
 
470}
471
472static int imx_mu_probe(struct platform_device *pdev)
473{
474	struct device *dev = &pdev->dev;
475	struct device_node *np = dev->of_node;
476	struct imx_mu_priv *priv;
477	const struct imx_mu_dcfg *dcfg;
478	int ret;
 
479
480	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
481	if (!priv)
482		return -ENOMEM;
483
484	priv->dev = dev;
485
486	priv->base = devm_platform_ioremap_resource(pdev, 0);
487	if (IS_ERR(priv->base))
488		return PTR_ERR(priv->base);
489
490	priv->irq = platform_get_irq(pdev, 0);
491	if (priv->irq < 0)
492		return priv->irq;
493
494	dcfg = of_device_get_match_data(dev);
495	if (!dcfg)
496		return -EINVAL;
497	priv->dcfg = dcfg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
498
499	priv->clk = devm_clk_get(dev, NULL);
500	if (IS_ERR(priv->clk)) {
501		if (PTR_ERR(priv->clk) != -ENOENT)
502			return PTR_ERR(priv->clk);
503
504		priv->clk = NULL;
505	}
506
507	ret = clk_prepare_enable(priv->clk);
508	if (ret) {
509		dev_err(dev, "Failed to enable clock\n");
510		return ret;
511	}
512
513	priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
514
515	priv->dcfg->init(priv);
516
517	spin_lock_init(&priv->xcr_lock);
518
519	priv->mbox.dev = dev;
520	priv->mbox.ops = &imx_mu_ops;
521	priv->mbox.chans = priv->mbox_chans;
522	priv->mbox.txdone_irq = true;
523
524	platform_set_drvdata(pdev, priv);
525
526	ret = devm_mbox_controller_register(dev, &priv->mbox);
527	if (ret) {
528		clk_disable_unprepare(priv->clk);
529		return ret;
530	}
531
532	pm_runtime_enable(dev);
533
534	ret = pm_runtime_get_sync(dev);
535	if (ret < 0) {
536		pm_runtime_put_noidle(dev);
537		goto disable_runtime_pm;
538	}
539
540	ret = pm_runtime_put_sync(dev);
541	if (ret < 0)
542		goto disable_runtime_pm;
543
544	clk_disable_unprepare(priv->clk);
545
546	return 0;
547
548disable_runtime_pm:
549	pm_runtime_disable(dev);
550	clk_disable_unprepare(priv->clk);
551	return ret;
552}
553
554static int imx_mu_remove(struct platform_device *pdev)
555{
556	struct imx_mu_priv *priv = platform_get_drvdata(pdev);
557
558	pm_runtime_disable(priv->dev);
559
560	return 0;
561}
562
563static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
564	.tx	= imx_mu_generic_tx,
565	.rx	= imx_mu_generic_rx,
 
566	.init	= imx_mu_init_generic,
567	.xTR	= {0x0, 0x4, 0x8, 0xc},
568	.xRR	= {0x10, 0x14, 0x18, 0x1c},
569	.xSR	= 0x20,
570	.xCR	= 0x24,
571};
572
573static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
574	.tx	= imx_mu_generic_tx,
575	.rx	= imx_mu_generic_rx,
 
 
 
 
 
 
 
 
 
 
 
 
576	.init	= imx_mu_init_generic,
577	.xTR	= {0x20, 0x24, 0x28, 0x2c},
578	.xRR	= {0x40, 0x44, 0x48, 0x4c},
579	.xSR	= 0x60,
580	.xCR	= 0x64,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
581};
582
583static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = {
584	.tx	= imx_mu_scu_tx,
585	.rx	= imx_mu_scu_rx,
586	.init	= imx_mu_init_scu,
587	.xTR	= {0x0, 0x4, 0x8, 0xc},
588	.xRR	= {0x10, 0x14, 0x18, 0x1c},
589	.xSR	= 0x20,
590	.xCR	= 0x24,
 
 
 
 
 
 
 
 
 
 
 
 
591};
592
593static const struct of_device_id imx_mu_dt_ids[] = {
594	{ .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },
595	{ .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx },
 
 
 
596	{ .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu },
 
597	{ },
598};
599MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
600
601static int __maybe_unused imx_mu_suspend_noirq(struct device *dev)
602{
603	struct imx_mu_priv *priv = dev_get_drvdata(dev);
 
 
 
 
 
 
604
605	if (!priv->clk)
606		priv->xcr = imx_mu_read(priv, priv->dcfg->xCR);
607
608	return 0;
609}
610
611static int __maybe_unused imx_mu_resume_noirq(struct device *dev)
612{
613	struct imx_mu_priv *priv = dev_get_drvdata(dev);
 
614
615	/*
616	 * ONLY restore MU when context lost, the TIE could
617	 * be set during noirq resume as there is MU data
618	 * communication going on, and restore the saved
619	 * value will overwrite the TIE and cause MU data
620	 * send failed, may lead to system freeze. This issue
621	 * is observed by testing freeze mode suspend.
622	 */
623	if (!imx_mu_read(priv, priv->dcfg->xCR) && !priv->clk)
624		imx_mu_write(priv, priv->xcr, priv->dcfg->xCR);
 
 
 
 
625
626	return 0;
627}
628
629static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
630{
631	struct imx_mu_priv *priv = dev_get_drvdata(dev);
632
633	clk_disable_unprepare(priv->clk);
634
635	return 0;
636}
637
638static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
639{
640	struct imx_mu_priv *priv = dev_get_drvdata(dev);
641	int ret;
642
643	ret = clk_prepare_enable(priv->clk);
644	if (ret)
645		dev_err(dev, "failed to enable clock\n");
646
647	return ret;
648}
649
650static const struct dev_pm_ops imx_mu_pm_ops = {
651	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq,
652				      imx_mu_resume_noirq)
653	SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
654			   imx_mu_runtime_resume, NULL)
655};
656
657static struct platform_driver imx_mu_driver = {
658	.probe		= imx_mu_probe,
659	.remove		= imx_mu_remove,
660	.driver = {
661		.name	= "imx_mu",
662		.of_match_table = imx_mu_dt_ids,
663		.pm = &imx_mu_pm_ops,
664	},
665};
666module_platform_driver(imx_mu_driver);
667
668MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
669MODULE_DESCRIPTION("Message Unit driver for i.MX");
670MODULE_LICENSE("GPL v2");