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v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * OMAP mailbox driver
  4 *
  5 * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
  6 * Copyright (C) 2013-2021 Texas Instruments Incorporated - https://www.ti.com
  7 *
  8 * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
  9 *          Suman Anna <s-anna@ti.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 10 */
 11
 12#include <linux/interrupt.h>
 13#include <linux/spinlock.h>
 14#include <linux/mutex.h>
 15#include <linux/slab.h>
 16#include <linux/kfifo.h>
 17#include <linux/err.h>
 18#include <linux/module.h>
 19#include <linux/of.h>
 20#include <linux/platform_device.h>
 21#include <linux/pm_runtime.h>
 
 22#include <linux/omap-mailbox.h>
 23#include <linux/mailbox_controller.h>
 24#include <linux/mailbox_client.h>
 25
 26#include "mailbox.h"
 27
 28#define MAILBOX_REVISION		0x000
 29#define MAILBOX_MESSAGE(m)		(0x040 + 4 * (m))
 30#define MAILBOX_FIFOSTATUS(m)		(0x080 + 4 * (m))
 31#define MAILBOX_MSGSTATUS(m)		(0x0c0 + 4 * (m))
 32
 33#define OMAP2_MAILBOX_IRQSTATUS(u)	(0x100 + 8 * (u))
 34#define OMAP2_MAILBOX_IRQENABLE(u)	(0x104 + 8 * (u))
 35
 36#define OMAP4_MAILBOX_IRQSTATUS(u)	(0x104 + 0x10 * (u))
 37#define OMAP4_MAILBOX_IRQENABLE(u)	(0x108 + 0x10 * (u))
 38#define OMAP4_MAILBOX_IRQENABLE_CLR(u)	(0x10c + 0x10 * (u))
 39
 40#define MAILBOX_IRQSTATUS(type, u)	(type ? OMAP4_MAILBOX_IRQSTATUS(u) : \
 41						OMAP2_MAILBOX_IRQSTATUS(u))
 42#define MAILBOX_IRQENABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE(u) : \
 43						OMAP2_MAILBOX_IRQENABLE(u))
 44#define MAILBOX_IRQDISABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE_CLR(u) \
 45						: OMAP2_MAILBOX_IRQENABLE(u))
 46
 47#define MAILBOX_IRQ_NEWMSG(m)		(1 << (2 * (m)))
 48#define MAILBOX_IRQ_NOTFULL(m)		(1 << (2 * (m) + 1))
 49
 50/* Interrupt register configuration types */
 51#define MBOX_INTR_CFG_TYPE1		0
 52#define MBOX_INTR_CFG_TYPE2		1
 
 
 
 53
 54struct omap_mbox_fifo {
 55	unsigned long msg;
 56	unsigned long fifo_stat;
 57	unsigned long msg_stat;
 58	unsigned long irqenable;
 59	unsigned long irqstatus;
 60	unsigned long irqdisable;
 61	u32 intr_bit;
 62};
 63
 64struct omap_mbox_queue {
 65	spinlock_t		lock;
 66	struct kfifo		fifo;
 67	struct work_struct	work;
 68	struct omap_mbox	*mbox;
 69	bool full;
 70};
 71
 72struct omap_mbox_match_data {
 73	u32 intr_type;
 74};
 75
 76struct omap_mbox_device {
 77	struct device *dev;
 78	struct mutex cfg_lock;
 79	void __iomem *mbox_base;
 80	u32 *irq_ctx;
 81	u32 num_users;
 82	u32 num_fifos;
 83	u32 intr_type;
 84	struct omap_mbox **mboxes;
 85	struct mbox_controller controller;
 86	struct list_head elem;
 87};
 88
 89struct omap_mbox_fifo_info {
 90	int tx_id;
 91	int tx_usr;
 92	int tx_irq;
 93
 94	int rx_id;
 95	int rx_usr;
 96	int rx_irq;
 97
 98	const char *name;
 99	bool send_no_irq;
100};
101
102struct omap_mbox {
103	const char		*name;
104	int			irq;
105	struct omap_mbox_queue	*rxq;
106	struct device		*dev;
107	struct omap_mbox_device *parent;
108	struct omap_mbox_fifo	tx_fifo;
109	struct omap_mbox_fifo	rx_fifo;
 
110	u32			intr_type;
111	struct mbox_chan	*chan;
112	bool			send_no_irq;
113};
114
115/* global variables for the mailbox devices */
116static DEFINE_MUTEX(omap_mbox_devices_lock);
117static LIST_HEAD(omap_mbox_devices);
118
119static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
120module_param(mbox_kfifo_size, uint, S_IRUGO);
121MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
122
123static struct omap_mbox *mbox_chan_to_omap_mbox(struct mbox_chan *chan)
124{
125	if (!chan || !chan->con_priv)
126		return NULL;
127
128	return (struct omap_mbox *)chan->con_priv;
129}
130
131static inline
132unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs)
133{
134	return __raw_readl(mdev->mbox_base + ofs);
135}
136
137static inline
138void mbox_write_reg(struct omap_mbox_device *mdev, u32 val, size_t ofs)
139{
140	__raw_writel(val, mdev->mbox_base + ofs);
141}
142
143/* Mailbox FIFO handle functions */
144static u32 mbox_fifo_read(struct omap_mbox *mbox)
145{
146	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
147
148	return mbox_read_reg(mbox->parent, fifo->msg);
149}
150
151static void mbox_fifo_write(struct omap_mbox *mbox, u32 msg)
152{
153	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
154
155	mbox_write_reg(mbox->parent, msg, fifo->msg);
156}
157
158static int mbox_fifo_empty(struct omap_mbox *mbox)
159{
160	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
161
162	return (mbox_read_reg(mbox->parent, fifo->msg_stat) == 0);
163}
164
165static int mbox_fifo_full(struct omap_mbox *mbox)
166{
167	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
168
169	return mbox_read_reg(mbox->parent, fifo->fifo_stat);
170}
171
172/* Mailbox IRQ handle functions */
173static void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
174{
175	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
176				&mbox->tx_fifo : &mbox->rx_fifo;
177	u32 bit = fifo->intr_bit;
178	u32 irqstatus = fifo->irqstatus;
179
180	mbox_write_reg(mbox->parent, bit, irqstatus);
181
182	/* Flush posted write for irq status to avoid spurious interrupts */
183	mbox_read_reg(mbox->parent, irqstatus);
184}
185
186static int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
187{
188	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
189				&mbox->tx_fifo : &mbox->rx_fifo;
190	u32 bit = fifo->intr_bit;
191	u32 irqenable = fifo->irqenable;
192	u32 irqstatus = fifo->irqstatus;
193
194	u32 enable = mbox_read_reg(mbox->parent, irqenable);
195	u32 status = mbox_read_reg(mbox->parent, irqstatus);
196
197	return (int)(enable & status & bit);
198}
199
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
200static void _omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
201{
202	u32 l;
203	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
204				&mbox->tx_fifo : &mbox->rx_fifo;
205	u32 bit = fifo->intr_bit;
206	u32 irqenable = fifo->irqenable;
207
208	l = mbox_read_reg(mbox->parent, irqenable);
209	l |= bit;
210	mbox_write_reg(mbox->parent, l, irqenable);
211}
212
213static void _omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
214{
215	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
216				&mbox->tx_fifo : &mbox->rx_fifo;
217	u32 bit = fifo->intr_bit;
218	u32 irqdisable = fifo->irqdisable;
219
220	/*
221	 * Read and update the interrupt configuration register for pre-OMAP4.
222	 * OMAP4 and later SoCs have a dedicated interrupt disabling register.
223	 */
224	if (!mbox->intr_type)
225		bit = mbox_read_reg(mbox->parent, irqdisable) & ~bit;
226
227	mbox_write_reg(mbox->parent, bit, irqdisable);
228}
229
230void omap_mbox_enable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
231{
232	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
233
234	if (WARN_ON(!mbox))
235		return;
236
237	_omap_mbox_enable_irq(mbox, irq);
238}
239EXPORT_SYMBOL(omap_mbox_enable_irq);
240
241void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
242{
243	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
244
245	if (WARN_ON(!mbox))
246		return;
247
248	_omap_mbox_disable_irq(mbox, irq);
249}
250EXPORT_SYMBOL(omap_mbox_disable_irq);
251
252/*
253 * Message receiver(workqueue)
254 */
255static void mbox_rx_work(struct work_struct *work)
256{
257	struct omap_mbox_queue *mq =
258			container_of(work, struct omap_mbox_queue, work);
259	mbox_msg_t data;
260	u32 msg;
261	int len;
262
263	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
264		len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
265		WARN_ON(len != sizeof(msg));
266		data = msg;
267
268		mbox_chan_received_data(mq->mbox->chan, (void *)data);
269		spin_lock_irq(&mq->lock);
270		if (mq->full) {
271			mq->full = false;
272			_omap_mbox_enable_irq(mq->mbox, IRQ_RX);
273		}
274		spin_unlock_irq(&mq->lock);
275	}
276}
277
278/*
279 * Mailbox interrupt handler
280 */
281static void __mbox_tx_interrupt(struct omap_mbox *mbox)
282{
283	_omap_mbox_disable_irq(mbox, IRQ_TX);
284	ack_mbox_irq(mbox, IRQ_TX);
285	mbox_chan_txdone(mbox->chan, 0);
286}
287
288static void __mbox_rx_interrupt(struct omap_mbox *mbox)
289{
290	struct omap_mbox_queue *mq = mbox->rxq;
291	u32 msg;
292	int len;
293
294	while (!mbox_fifo_empty(mbox)) {
295		if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
296			_omap_mbox_disable_irq(mbox, IRQ_RX);
297			mq->full = true;
298			goto nomem;
299		}
300
301		msg = mbox_fifo_read(mbox);
302
303		len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
304		WARN_ON(len != sizeof(msg));
305	}
306
307	/* no more messages in the fifo. clear IRQ source. */
308	ack_mbox_irq(mbox, IRQ_RX);
309nomem:
310	schedule_work(&mbox->rxq->work);
311}
312
313static irqreturn_t mbox_interrupt(int irq, void *p)
314{
315	struct omap_mbox *mbox = p;
316
317	if (is_mbox_irq(mbox, IRQ_TX))
318		__mbox_tx_interrupt(mbox);
319
320	if (is_mbox_irq(mbox, IRQ_RX))
321		__mbox_rx_interrupt(mbox);
322
323	return IRQ_HANDLED;
324}
325
326static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
327					void (*work)(struct work_struct *))
328{
329	struct omap_mbox_queue *mq;
330
331	if (!work)
332		return NULL;
333
334	mq = kzalloc(sizeof(*mq), GFP_KERNEL);
335	if (!mq)
336		return NULL;
337
338	spin_lock_init(&mq->lock);
339
340	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
341		goto error;
342
343	INIT_WORK(&mq->work, work);
344	return mq;
345
346error:
347	kfree(mq);
348	return NULL;
349}
350
351static void mbox_queue_free(struct omap_mbox_queue *q)
352{
353	kfifo_free(&q->fifo);
354	kfree(q);
355}
356
357static int omap_mbox_startup(struct omap_mbox *mbox)
358{
359	int ret = 0;
360	struct omap_mbox_queue *mq;
361
362	mq = mbox_queue_alloc(mbox, mbox_rx_work);
363	if (!mq)
364		return -ENOMEM;
365	mbox->rxq = mq;
366	mq->mbox = mbox;
367
368	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
369			  mbox->name, mbox);
370	if (unlikely(ret)) {
371		pr_err("failed to register mailbox interrupt:%d\n", ret);
372		goto fail_request_irq;
373	}
374
375	if (mbox->send_no_irq)
376		mbox->chan->txdone_method = TXDONE_BY_ACK;
377
378	_omap_mbox_enable_irq(mbox, IRQ_RX);
379
380	return 0;
381
382fail_request_irq:
383	mbox_queue_free(mbox->rxq);
384	return ret;
385}
386
387static void omap_mbox_fini(struct omap_mbox *mbox)
388{
389	_omap_mbox_disable_irq(mbox, IRQ_RX);
390	free_irq(mbox->irq, mbox);
391	flush_work(&mbox->rxq->work);
392	mbox_queue_free(mbox->rxq);
393}
394
395static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev,
396					       const char *mbox_name)
397{
398	struct omap_mbox *_mbox, *mbox = NULL;
399	struct omap_mbox **mboxes = mdev->mboxes;
400	int i;
401
402	if (!mboxes)
403		return NULL;
404
405	for (i = 0; (_mbox = mboxes[i]); i++) {
406		if (!strcmp(_mbox->name, mbox_name)) {
407			mbox = _mbox;
408			break;
409		}
410	}
411	return mbox;
412}
413
414struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl,
415					    const char *chan_name)
416{
417	struct device *dev = cl->dev;
418	struct omap_mbox *mbox = NULL;
419	struct omap_mbox_device *mdev;
 
 
420	int ret;
421
422	if (!dev)
423		return ERR_PTR(-ENODEV);
424
425	if (dev->of_node) {
426		pr_err("%s: please use mbox_request_channel(), this API is supported only for OMAP non-DT usage\n",
427		       __func__);
428		return ERR_PTR(-ENODEV);
429	}
430
431	mutex_lock(&omap_mbox_devices_lock);
432	list_for_each_entry(mdev, &omap_mbox_devices, elem) {
433		mbox = omap_mbox_device_find(mdev, chan_name);
434		if (mbox)
435			break;
436	}
437	mutex_unlock(&omap_mbox_devices_lock);
438
439	if (!mbox || !mbox->chan)
440		return ERR_PTR(-ENOENT);
441
442	ret = mbox_bind_client(mbox->chan, cl);
443	if (ret)
444		return ERR_PTR(ret);
 
 
 
 
 
 
 
 
 
 
 
 
445
446	return mbox->chan;
447}
448EXPORT_SYMBOL(omap_mbox_request_channel);
449
450static struct class omap_mbox_class = { .name = "mbox", };
451
452static int omap_mbox_register(struct omap_mbox_device *mdev)
453{
454	int ret;
455	int i;
456	struct omap_mbox **mboxes;
457
458	if (!mdev || !mdev->mboxes)
459		return -EINVAL;
460
461	mboxes = mdev->mboxes;
462	for (i = 0; mboxes[i]; i++) {
463		struct omap_mbox *mbox = mboxes[i];
464
465		mbox->dev = device_create(&omap_mbox_class, mdev->dev,
466					0, mbox, "%s", mbox->name);
467		if (IS_ERR(mbox->dev)) {
468			ret = PTR_ERR(mbox->dev);
469			goto err_out;
470		}
471	}
472
473	mutex_lock(&omap_mbox_devices_lock);
474	list_add(&mdev->elem, &omap_mbox_devices);
475	mutex_unlock(&omap_mbox_devices_lock);
476
477	ret = devm_mbox_controller_register(mdev->dev, &mdev->controller);
478
479err_out:
480	if (ret) {
481		while (i--)
482			device_unregister(mboxes[i]->dev);
483	}
484	return ret;
485}
486
487static int omap_mbox_unregister(struct omap_mbox_device *mdev)
488{
489	int i;
490	struct omap_mbox **mboxes;
491
492	if (!mdev || !mdev->mboxes)
493		return -EINVAL;
494
495	mutex_lock(&omap_mbox_devices_lock);
496	list_del(&mdev->elem);
497	mutex_unlock(&omap_mbox_devices_lock);
498
 
 
499	mboxes = mdev->mboxes;
500	for (i = 0; mboxes[i]; i++)
501		device_unregister(mboxes[i]->dev);
502	return 0;
503}
504
505static int omap_mbox_chan_startup(struct mbox_chan *chan)
506{
507	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
508	struct omap_mbox_device *mdev = mbox->parent;
509	int ret = 0;
510
511	mutex_lock(&mdev->cfg_lock);
512	pm_runtime_get_sync(mdev->dev);
513	ret = omap_mbox_startup(mbox);
514	if (ret)
515		pm_runtime_put_sync(mdev->dev);
516	mutex_unlock(&mdev->cfg_lock);
517	return ret;
518}
519
520static void omap_mbox_chan_shutdown(struct mbox_chan *chan)
521{
522	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
523	struct omap_mbox_device *mdev = mbox->parent;
524
525	mutex_lock(&mdev->cfg_lock);
526	omap_mbox_fini(mbox);
527	pm_runtime_put_sync(mdev->dev);
528	mutex_unlock(&mdev->cfg_lock);
529}
530
531static int omap_mbox_chan_send_noirq(struct omap_mbox *mbox, u32 msg)
532{
533	int ret = -EBUSY;
534
535	if (!mbox_fifo_full(mbox)) {
536		_omap_mbox_enable_irq(mbox, IRQ_RX);
537		mbox_fifo_write(mbox, msg);
538		ret = 0;
539		_omap_mbox_disable_irq(mbox, IRQ_RX);
540
541		/* we must read and ack the interrupt directly from here */
542		mbox_fifo_read(mbox);
543		ack_mbox_irq(mbox, IRQ_RX);
544	}
545
546	return ret;
547}
548
549static int omap_mbox_chan_send(struct omap_mbox *mbox, u32 msg)
550{
551	int ret = -EBUSY;
552
553	if (!mbox_fifo_full(mbox)) {
554		mbox_fifo_write(mbox, msg);
555		ret = 0;
556	}
557
558	/* always enable the interrupt */
559	_omap_mbox_enable_irq(mbox, IRQ_TX);
560	return ret;
561}
562
563static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data)
564{
565	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
566	int ret;
567	u32 msg = omap_mbox_message(data);
568
569	if (!mbox)
570		return -EINVAL;
571
572	if (mbox->send_no_irq)
573		ret = omap_mbox_chan_send_noirq(mbox, msg);
574	else
575		ret = omap_mbox_chan_send(mbox, msg);
576
577	return ret;
578}
579
580static const struct mbox_chan_ops omap_mbox_chan_ops = {
581	.startup        = omap_mbox_chan_startup,
582	.send_data      = omap_mbox_chan_send_data,
583	.shutdown       = omap_mbox_chan_shutdown,
584};
585
586#ifdef CONFIG_PM_SLEEP
587static int omap_mbox_suspend(struct device *dev)
588{
589	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
590	u32 usr, fifo, reg;
591
592	if (pm_runtime_status_suspended(dev))
593		return 0;
594
595	for (fifo = 0; fifo < mdev->num_fifos; fifo++) {
596		if (mbox_read_reg(mdev, MAILBOX_MSGSTATUS(fifo))) {
597			dev_err(mdev->dev, "fifo %d has unexpected unread messages\n",
598				fifo);
599			return -EBUSY;
600		}
601	}
602
603	for (usr = 0; usr < mdev->num_users; usr++) {
604		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
605		mdev->irq_ctx[usr] = mbox_read_reg(mdev, reg);
606	}
607
608	return 0;
609}
610
611static int omap_mbox_resume(struct device *dev)
612{
613	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
614	u32 usr, reg;
615
616	if (pm_runtime_status_suspended(dev))
617		return 0;
618
619	for (usr = 0; usr < mdev->num_users; usr++) {
620		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
621		mbox_write_reg(mdev, mdev->irq_ctx[usr], reg);
622	}
623
624	return 0;
625}
626#endif
627
628static const struct dev_pm_ops omap_mbox_pm_ops = {
629	SET_SYSTEM_SLEEP_PM_OPS(omap_mbox_suspend, omap_mbox_resume)
630};
631
632static const struct omap_mbox_match_data omap2_data = { MBOX_INTR_CFG_TYPE1 };
633static const struct omap_mbox_match_data omap4_data = { MBOX_INTR_CFG_TYPE2 };
634
635static const struct of_device_id omap_mailbox_of_match[] = {
636	{
637		.compatible	= "ti,omap2-mailbox",
638		.data		= &omap2_data,
639	},
640	{
641		.compatible	= "ti,omap3-mailbox",
642		.data		= &omap2_data,
643	},
644	{
645		.compatible	= "ti,omap4-mailbox",
646		.data		= &omap4_data,
647	},
648	{
649		.compatible	= "ti,am654-mailbox",
650		.data		= &omap4_data,
651	},
652	{
653		.compatible	= "ti,am64-mailbox",
654		.data		= &omap4_data,
655	},
656	{
657		/* end */
658	},
659};
660MODULE_DEVICE_TABLE(of, omap_mailbox_of_match);
661
662static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
663					    const struct of_phandle_args *sp)
664{
665	phandle phandle = sp->args[0];
666	struct device_node *node;
667	struct omap_mbox_device *mdev;
668	struct omap_mbox *mbox;
669
670	mdev = container_of(controller, struct omap_mbox_device, controller);
671	if (WARN_ON(!mdev))
672		return ERR_PTR(-EINVAL);
673
674	node = of_find_node_by_phandle(phandle);
675	if (!node) {
676		pr_err("%s: could not find node phandle 0x%x\n",
677		       __func__, phandle);
678		return ERR_PTR(-ENODEV);
679	}
680
681	mbox = omap_mbox_device_find(mdev, node->name);
682	of_node_put(node);
683	return mbox ? mbox->chan : ERR_PTR(-ENOENT);
684}
685
686static int omap_mbox_probe(struct platform_device *pdev)
687{
 
688	int ret;
689	struct mbox_chan *chnls;
690	struct omap_mbox **list, *mbox, *mboxblk;
 
 
691	struct omap_mbox_fifo_info *finfo, *finfoblk;
692	struct omap_mbox_device *mdev;
693	struct omap_mbox_fifo *fifo;
694	struct device_node *node = pdev->dev.of_node;
695	struct device_node *child;
696	const struct omap_mbox_match_data *match_data;
697	u32 intr_type, info_count;
698	u32 num_users, num_fifos;
699	u32 tmp[3];
700	u32 l;
701	int i;
702
703	if (!node) {
704		pr_err("%s: only DT-based devices are supported\n", __func__);
705		return -ENODEV;
706	}
707
708	match_data = of_device_get_match_data(&pdev->dev);
709	if (!match_data)
710		return -ENODEV;
711	intr_type = match_data->intr_type;
712
713	if (of_property_read_u32(node, "ti,mbox-num-users", &num_users))
714		return -ENODEV;
715
716	if (of_property_read_u32(node, "ti,mbox-num-fifos", &num_fifos))
717		return -ENODEV;
718
719	info_count = of_get_available_child_count(node);
720	if (!info_count) {
721		dev_err(&pdev->dev, "no available mbox devices found\n");
722		return -ENODEV;
 
 
 
 
 
 
 
 
 
 
723	}
724
725	finfoblk = devm_kcalloc(&pdev->dev, info_count, sizeof(*finfoblk),
726				GFP_KERNEL);
727	if (!finfoblk)
728		return -ENOMEM;
729
730	finfo = finfoblk;
731	child = NULL;
732	for (i = 0; i < info_count; i++, finfo++) {
733		child = of_get_next_available_child(node, child);
734		ret = of_property_read_u32_array(child, "ti,mbox-tx", tmp,
735						 ARRAY_SIZE(tmp));
736		if (ret)
737			return ret;
738		finfo->tx_id = tmp[0];
739		finfo->tx_irq = tmp[1];
740		finfo->tx_usr = tmp[2];
741
742		ret = of_property_read_u32_array(child, "ti,mbox-rx", tmp,
743						 ARRAY_SIZE(tmp));
744		if (ret)
745			return ret;
746		finfo->rx_id = tmp[0];
747		finfo->rx_irq = tmp[1];
748		finfo->rx_usr = tmp[2];
749
750		finfo->name = child->name;
751
752		finfo->send_no_irq = of_property_read_bool(child, "ti,mbox-send-noirq");
753
 
 
 
 
 
 
 
 
 
 
 
754		if (finfo->tx_id >= num_fifos || finfo->rx_id >= num_fifos ||
755		    finfo->tx_usr >= num_users || finfo->rx_usr >= num_users)
756			return -EINVAL;
757	}
758
759	mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_KERNEL);
760	if (!mdev)
761		return -ENOMEM;
762
763	mdev->mbox_base = devm_platform_ioremap_resource(pdev, 0);
 
764	if (IS_ERR(mdev->mbox_base))
765		return PTR_ERR(mdev->mbox_base);
766
767	mdev->irq_ctx = devm_kcalloc(&pdev->dev, num_users, sizeof(u32),
768				     GFP_KERNEL);
769	if (!mdev->irq_ctx)
770		return -ENOMEM;
771
772	/* allocate one extra for marking end of list */
773	list = devm_kcalloc(&pdev->dev, info_count + 1, sizeof(*list),
774			    GFP_KERNEL);
775	if (!list)
776		return -ENOMEM;
777
778	chnls = devm_kcalloc(&pdev->dev, info_count + 1, sizeof(*chnls),
779			     GFP_KERNEL);
780	if (!chnls)
781		return -ENOMEM;
782
783	mboxblk = devm_kcalloc(&pdev->dev, info_count, sizeof(*mbox),
784			       GFP_KERNEL);
785	if (!mboxblk)
786		return -ENOMEM;
787
788	mbox = mboxblk;
789	finfo = finfoblk;
790	for (i = 0; i < info_count; i++, finfo++) {
791		fifo = &mbox->tx_fifo;
792		fifo->msg = MAILBOX_MESSAGE(finfo->tx_id);
793		fifo->fifo_stat = MAILBOX_FIFOSTATUS(finfo->tx_id);
794		fifo->intr_bit = MAILBOX_IRQ_NOTFULL(finfo->tx_id);
795		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, finfo->tx_usr);
796		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, finfo->tx_usr);
797		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, finfo->tx_usr);
798
799		fifo = &mbox->rx_fifo;
800		fifo->msg = MAILBOX_MESSAGE(finfo->rx_id);
801		fifo->msg_stat =  MAILBOX_MSGSTATUS(finfo->rx_id);
802		fifo->intr_bit = MAILBOX_IRQ_NEWMSG(finfo->rx_id);
803		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, finfo->rx_usr);
804		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, finfo->rx_usr);
805		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, finfo->rx_usr);
806
807		mbox->send_no_irq = finfo->send_no_irq;
808		mbox->intr_type = intr_type;
809
810		mbox->parent = mdev;
811		mbox->name = finfo->name;
812		mbox->irq = platform_get_irq(pdev, finfo->tx_irq);
813		if (mbox->irq < 0)
814			return mbox->irq;
815		mbox->chan = &chnls[i];
816		chnls[i].con_priv = mbox;
817		list[i] = mbox++;
818	}
819
820	mutex_init(&mdev->cfg_lock);
821	mdev->dev = &pdev->dev;
822	mdev->num_users = num_users;
823	mdev->num_fifos = num_fifos;
824	mdev->intr_type = intr_type;
825	mdev->mboxes = list;
826
827	/*
828	 * OMAP/K3 Mailbox IP does not have a Tx-Done IRQ, but rather a Tx-Ready
829	 * IRQ and is needed to run the Tx state machine
830	 */
831	mdev->controller.txdone_irq = true;
832	mdev->controller.dev = mdev->dev;
833	mdev->controller.ops = &omap_mbox_chan_ops;
834	mdev->controller.chans = chnls;
835	mdev->controller.num_chans = info_count;
836	mdev->controller.of_xlate = omap_mbox_of_xlate;
837	ret = omap_mbox_register(mdev);
838	if (ret)
839		return ret;
840
841	platform_set_drvdata(pdev, mdev);
842	pm_runtime_enable(mdev->dev);
843
844	ret = pm_runtime_resume_and_get(mdev->dev);
845	if (ret < 0)
 
846		goto unregister;
 
847
848	/*
849	 * just print the raw revision register, the format is not
850	 * uniform across all SoCs
851	 */
852	l = mbox_read_reg(mdev, MAILBOX_REVISION);
853	dev_info(mdev->dev, "omap mailbox rev 0x%x\n", l);
854
855	ret = pm_runtime_put_sync(mdev->dev);
856	if (ret < 0 && ret != -ENOSYS)
857		goto unregister;
858
859	devm_kfree(&pdev->dev, finfoblk);
860	return 0;
861
862unregister:
863	pm_runtime_disable(mdev->dev);
864	omap_mbox_unregister(mdev);
865	return ret;
866}
867
868static void omap_mbox_remove(struct platform_device *pdev)
869{
870	struct omap_mbox_device *mdev = platform_get_drvdata(pdev);
871
872	pm_runtime_disable(mdev->dev);
873	omap_mbox_unregister(mdev);
 
 
874}
875
876static struct platform_driver omap_mbox_driver = {
877	.probe	= omap_mbox_probe,
878	.remove_new = omap_mbox_remove,
879	.driver	= {
880		.name = "omap-mailbox",
881		.pm = &omap_mbox_pm_ops,
882		.of_match_table = of_match_ptr(omap_mailbox_of_match),
883	},
884};
885
886static int __init omap_mbox_init(void)
887{
888	int err;
889
890	err = class_register(&omap_mbox_class);
891	if (err)
892		return err;
893
894	/* kfifo size sanity check: alignment and minimal size */
895	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(u32));
896	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size, sizeof(u32));
897
898	err = platform_driver_register(&omap_mbox_driver);
899	if (err)
900		class_unregister(&omap_mbox_class);
901
902	return err;
903}
904subsys_initcall(omap_mbox_init);
905
906static void __exit omap_mbox_exit(void)
907{
908	platform_driver_unregister(&omap_mbox_driver);
909	class_unregister(&omap_mbox_class);
910}
911module_exit(omap_mbox_exit);
912
913MODULE_LICENSE("GPL v2");
914MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
915MODULE_AUTHOR("Toshihiro Kobayashi");
916MODULE_AUTHOR("Hiroshi DOYU");
v4.6
 
  1/*
  2 * OMAP mailbox driver
  3 *
  4 * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
  5 * Copyright (C) 2013-2014 Texas Instruments Inc.
  6 *
  7 * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
  8 *          Suman Anna <s-anna@ti.com>
  9 *
 10 * This program is free software; you can redistribute it and/or
 11 * modify it under the terms of the GNU General Public License
 12 * version 2 as published by the Free Software Foundation.
 13 *
 14 * This program is distributed in the hope that it will be useful, but
 15 * WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17 * General Public License for more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program; if not, write to the Free Software
 21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 22 * 02110-1301 USA
 23 *
 24 */
 25
 26#include <linux/interrupt.h>
 27#include <linux/spinlock.h>
 28#include <linux/mutex.h>
 29#include <linux/slab.h>
 30#include <linux/kfifo.h>
 31#include <linux/err.h>
 32#include <linux/module.h>
 33#include <linux/of_device.h>
 34#include <linux/platform_device.h>
 35#include <linux/pm_runtime.h>
 36#include <linux/platform_data/mailbox-omap.h>
 37#include <linux/omap-mailbox.h>
 38#include <linux/mailbox_controller.h>
 39#include <linux/mailbox_client.h>
 40
 41#include "mailbox.h"
 42
 43#define MAILBOX_REVISION		0x000
 44#define MAILBOX_MESSAGE(m)		(0x040 + 4 * (m))
 45#define MAILBOX_FIFOSTATUS(m)		(0x080 + 4 * (m))
 46#define MAILBOX_MSGSTATUS(m)		(0x0c0 + 4 * (m))
 47
 48#define OMAP2_MAILBOX_IRQSTATUS(u)	(0x100 + 8 * (u))
 49#define OMAP2_MAILBOX_IRQENABLE(u)	(0x104 + 8 * (u))
 50
 51#define OMAP4_MAILBOX_IRQSTATUS(u)	(0x104 + 0x10 * (u))
 52#define OMAP4_MAILBOX_IRQENABLE(u)	(0x108 + 0x10 * (u))
 53#define OMAP4_MAILBOX_IRQENABLE_CLR(u)	(0x10c + 0x10 * (u))
 54
 55#define MAILBOX_IRQSTATUS(type, u)	(type ? OMAP4_MAILBOX_IRQSTATUS(u) : \
 56						OMAP2_MAILBOX_IRQSTATUS(u))
 57#define MAILBOX_IRQENABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE(u) : \
 58						OMAP2_MAILBOX_IRQENABLE(u))
 59#define MAILBOX_IRQDISABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE_CLR(u) \
 60						: OMAP2_MAILBOX_IRQENABLE(u))
 61
 62#define MAILBOX_IRQ_NEWMSG(m)		(1 << (2 * (m)))
 63#define MAILBOX_IRQ_NOTFULL(m)		(1 << (2 * (m) + 1))
 64
 65#define MBOX_REG_SIZE			0x120
 66
 67#define OMAP4_MBOX_REG_SIZE		0x130
 68
 69#define MBOX_NR_REGS			(MBOX_REG_SIZE / sizeof(u32))
 70#define OMAP4_MBOX_NR_REGS		(OMAP4_MBOX_REG_SIZE / sizeof(u32))
 71
 72struct omap_mbox_fifo {
 73	unsigned long msg;
 74	unsigned long fifo_stat;
 75	unsigned long msg_stat;
 76	unsigned long irqenable;
 77	unsigned long irqstatus;
 78	unsigned long irqdisable;
 79	u32 intr_bit;
 80};
 81
 82struct omap_mbox_queue {
 83	spinlock_t		lock;
 84	struct kfifo		fifo;
 85	struct work_struct	work;
 86	struct omap_mbox	*mbox;
 87	bool full;
 88};
 89
 
 
 
 
 90struct omap_mbox_device {
 91	struct device *dev;
 92	struct mutex cfg_lock;
 93	void __iomem *mbox_base;
 
 94	u32 num_users;
 95	u32 num_fifos;
 
 96	struct omap_mbox **mboxes;
 97	struct mbox_controller controller;
 98	struct list_head elem;
 99};
100
101struct omap_mbox_fifo_info {
102	int tx_id;
103	int tx_usr;
104	int tx_irq;
105
106	int rx_id;
107	int rx_usr;
108	int rx_irq;
109
110	const char *name;
111	bool send_no_irq;
112};
113
114struct omap_mbox {
115	const char		*name;
116	int			irq;
117	struct omap_mbox_queue	*rxq;
118	struct device		*dev;
119	struct omap_mbox_device *parent;
120	struct omap_mbox_fifo	tx_fifo;
121	struct omap_mbox_fifo	rx_fifo;
122	u32			ctx[OMAP4_MBOX_NR_REGS];
123	u32			intr_type;
124	struct mbox_chan	*chan;
125	bool			send_no_irq;
126};
127
128/* global variables for the mailbox devices */
129static DEFINE_MUTEX(omap_mbox_devices_lock);
130static LIST_HEAD(omap_mbox_devices);
131
132static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
133module_param(mbox_kfifo_size, uint, S_IRUGO);
134MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
135
136static struct omap_mbox *mbox_chan_to_omap_mbox(struct mbox_chan *chan)
137{
138	if (!chan || !chan->con_priv)
139		return NULL;
140
141	return (struct omap_mbox *)chan->con_priv;
142}
143
144static inline
145unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs)
146{
147	return __raw_readl(mdev->mbox_base + ofs);
148}
149
150static inline
151void mbox_write_reg(struct omap_mbox_device *mdev, u32 val, size_t ofs)
152{
153	__raw_writel(val, mdev->mbox_base + ofs);
154}
155
156/* Mailbox FIFO handle functions */
157static mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
158{
159	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
160	return (mbox_msg_t) mbox_read_reg(mbox->parent, fifo->msg);
 
161}
162
163static void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
164{
165	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
 
166	mbox_write_reg(mbox->parent, msg, fifo->msg);
167}
168
169static int mbox_fifo_empty(struct omap_mbox *mbox)
170{
171	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
 
172	return (mbox_read_reg(mbox->parent, fifo->msg_stat) == 0);
173}
174
175static int mbox_fifo_full(struct omap_mbox *mbox)
176{
177	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
 
178	return mbox_read_reg(mbox->parent, fifo->fifo_stat);
179}
180
181/* Mailbox IRQ handle functions */
182static void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
183{
184	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
185				&mbox->tx_fifo : &mbox->rx_fifo;
186	u32 bit = fifo->intr_bit;
187	u32 irqstatus = fifo->irqstatus;
188
189	mbox_write_reg(mbox->parent, bit, irqstatus);
190
191	/* Flush posted write for irq status to avoid spurious interrupts */
192	mbox_read_reg(mbox->parent, irqstatus);
193}
194
195static int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
196{
197	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
198				&mbox->tx_fifo : &mbox->rx_fifo;
199	u32 bit = fifo->intr_bit;
200	u32 irqenable = fifo->irqenable;
201	u32 irqstatus = fifo->irqstatus;
202
203	u32 enable = mbox_read_reg(mbox->parent, irqenable);
204	u32 status = mbox_read_reg(mbox->parent, irqstatus);
205
206	return (int)(enable & status & bit);
207}
208
209void omap_mbox_save_ctx(struct mbox_chan *chan)
210{
211	int i;
212	int nr_regs;
213	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
214
215	if (WARN_ON(!mbox))
216		return;
217
218	if (mbox->intr_type)
219		nr_regs = OMAP4_MBOX_NR_REGS;
220	else
221		nr_regs = MBOX_NR_REGS;
222	for (i = 0; i < nr_regs; i++) {
223		mbox->ctx[i] = mbox_read_reg(mbox->parent, i * sizeof(u32));
224
225		dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
226			i, mbox->ctx[i]);
227	}
228}
229EXPORT_SYMBOL(omap_mbox_save_ctx);
230
231void omap_mbox_restore_ctx(struct mbox_chan *chan)
232{
233	int i;
234	int nr_regs;
235	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
236
237	if (WARN_ON(!mbox))
238		return;
239
240	if (mbox->intr_type)
241		nr_regs = OMAP4_MBOX_NR_REGS;
242	else
243		nr_regs = MBOX_NR_REGS;
244	for (i = 0; i < nr_regs; i++) {
245		mbox_write_reg(mbox->parent, mbox->ctx[i], i * sizeof(u32));
246		dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
247			i, mbox->ctx[i]);
248	}
249}
250EXPORT_SYMBOL(omap_mbox_restore_ctx);
251
252static void _omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
253{
254	u32 l;
255	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
256				&mbox->tx_fifo : &mbox->rx_fifo;
257	u32 bit = fifo->intr_bit;
258	u32 irqenable = fifo->irqenable;
259
260	l = mbox_read_reg(mbox->parent, irqenable);
261	l |= bit;
262	mbox_write_reg(mbox->parent, l, irqenable);
263}
264
265static void _omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
266{
267	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
268				&mbox->tx_fifo : &mbox->rx_fifo;
269	u32 bit = fifo->intr_bit;
270	u32 irqdisable = fifo->irqdisable;
271
272	/*
273	 * Read and update the interrupt configuration register for pre-OMAP4.
274	 * OMAP4 and later SoCs have a dedicated interrupt disabling register.
275	 */
276	if (!mbox->intr_type)
277		bit = mbox_read_reg(mbox->parent, irqdisable) & ~bit;
278
279	mbox_write_reg(mbox->parent, bit, irqdisable);
280}
281
282void omap_mbox_enable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
283{
284	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
285
286	if (WARN_ON(!mbox))
287		return;
288
289	_omap_mbox_enable_irq(mbox, irq);
290}
291EXPORT_SYMBOL(omap_mbox_enable_irq);
292
293void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
294{
295	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
296
297	if (WARN_ON(!mbox))
298		return;
299
300	_omap_mbox_disable_irq(mbox, irq);
301}
302EXPORT_SYMBOL(omap_mbox_disable_irq);
303
304/*
305 * Message receiver(workqueue)
306 */
307static void mbox_rx_work(struct work_struct *work)
308{
309	struct omap_mbox_queue *mq =
310			container_of(work, struct omap_mbox_queue, work);
311	mbox_msg_t msg;
 
312	int len;
313
314	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
315		len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
316		WARN_ON(len != sizeof(msg));
 
317
318		mbox_chan_received_data(mq->mbox->chan, (void *)msg);
319		spin_lock_irq(&mq->lock);
320		if (mq->full) {
321			mq->full = false;
322			_omap_mbox_enable_irq(mq->mbox, IRQ_RX);
323		}
324		spin_unlock_irq(&mq->lock);
325	}
326}
327
328/*
329 * Mailbox interrupt handler
330 */
331static void __mbox_tx_interrupt(struct omap_mbox *mbox)
332{
333	_omap_mbox_disable_irq(mbox, IRQ_TX);
334	ack_mbox_irq(mbox, IRQ_TX);
335	mbox_chan_txdone(mbox->chan, 0);
336}
337
338static void __mbox_rx_interrupt(struct omap_mbox *mbox)
339{
340	struct omap_mbox_queue *mq = mbox->rxq;
341	mbox_msg_t msg;
342	int len;
343
344	while (!mbox_fifo_empty(mbox)) {
345		if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
346			_omap_mbox_disable_irq(mbox, IRQ_RX);
347			mq->full = true;
348			goto nomem;
349		}
350
351		msg = mbox_fifo_read(mbox);
352
353		len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
354		WARN_ON(len != sizeof(msg));
355	}
356
357	/* no more messages in the fifo. clear IRQ source. */
358	ack_mbox_irq(mbox, IRQ_RX);
359nomem:
360	schedule_work(&mbox->rxq->work);
361}
362
363static irqreturn_t mbox_interrupt(int irq, void *p)
364{
365	struct omap_mbox *mbox = p;
366
367	if (is_mbox_irq(mbox, IRQ_TX))
368		__mbox_tx_interrupt(mbox);
369
370	if (is_mbox_irq(mbox, IRQ_RX))
371		__mbox_rx_interrupt(mbox);
372
373	return IRQ_HANDLED;
374}
375
376static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
377					void (*work)(struct work_struct *))
378{
379	struct omap_mbox_queue *mq;
380
381	if (!work)
382		return NULL;
383
384	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
385	if (!mq)
386		return NULL;
387
388	spin_lock_init(&mq->lock);
389
390	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
391		goto error;
392
393	INIT_WORK(&mq->work, work);
394	return mq;
395
396error:
397	kfree(mq);
398	return NULL;
399}
400
401static void mbox_queue_free(struct omap_mbox_queue *q)
402{
403	kfifo_free(&q->fifo);
404	kfree(q);
405}
406
407static int omap_mbox_startup(struct omap_mbox *mbox)
408{
409	int ret = 0;
410	struct omap_mbox_queue *mq;
411
412	mq = mbox_queue_alloc(mbox, mbox_rx_work);
413	if (!mq)
414		return -ENOMEM;
415	mbox->rxq = mq;
416	mq->mbox = mbox;
417
418	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
419			  mbox->name, mbox);
420	if (unlikely(ret)) {
421		pr_err("failed to register mailbox interrupt:%d\n", ret);
422		goto fail_request_irq;
423	}
424
425	if (mbox->send_no_irq)
426		mbox->chan->txdone_method = TXDONE_BY_ACK;
427
428	_omap_mbox_enable_irq(mbox, IRQ_RX);
429
430	return 0;
431
432fail_request_irq:
433	mbox_queue_free(mbox->rxq);
434	return ret;
435}
436
437static void omap_mbox_fini(struct omap_mbox *mbox)
438{
439	_omap_mbox_disable_irq(mbox, IRQ_RX);
440	free_irq(mbox->irq, mbox);
441	flush_work(&mbox->rxq->work);
442	mbox_queue_free(mbox->rxq);
443}
444
445static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev,
446					       const char *mbox_name)
447{
448	struct omap_mbox *_mbox, *mbox = NULL;
449	struct omap_mbox **mboxes = mdev->mboxes;
450	int i;
451
452	if (!mboxes)
453		return NULL;
454
455	for (i = 0; (_mbox = mboxes[i]); i++) {
456		if (!strcmp(_mbox->name, mbox_name)) {
457			mbox = _mbox;
458			break;
459		}
460	}
461	return mbox;
462}
463
464struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl,
465					    const char *chan_name)
466{
467	struct device *dev = cl->dev;
468	struct omap_mbox *mbox = NULL;
469	struct omap_mbox_device *mdev;
470	struct mbox_chan *chan;
471	unsigned long flags;
472	int ret;
473
474	if (!dev)
475		return ERR_PTR(-ENODEV);
476
477	if (dev->of_node) {
478		pr_err("%s: please use mbox_request_channel(), this API is supported only for OMAP non-DT usage\n",
479		       __func__);
480		return ERR_PTR(-ENODEV);
481	}
482
483	mutex_lock(&omap_mbox_devices_lock);
484	list_for_each_entry(mdev, &omap_mbox_devices, elem) {
485		mbox = omap_mbox_device_find(mdev, chan_name);
486		if (mbox)
487			break;
488	}
489	mutex_unlock(&omap_mbox_devices_lock);
490
491	if (!mbox || !mbox->chan)
492		return ERR_PTR(-ENOENT);
493
494	chan = mbox->chan;
495	spin_lock_irqsave(&chan->lock, flags);
496	chan->msg_free = 0;
497	chan->msg_count = 0;
498	chan->active_req = NULL;
499	chan->cl = cl;
500	init_completion(&chan->tx_complete);
501	spin_unlock_irqrestore(&chan->lock, flags);
502
503	ret = chan->mbox->ops->startup(chan);
504	if (ret) {
505		pr_err("Unable to startup the chan (%d)\n", ret);
506		mbox_free_channel(chan);
507		chan = ERR_PTR(ret);
508	}
509
510	return chan;
511}
512EXPORT_SYMBOL(omap_mbox_request_channel);
513
514static struct class omap_mbox_class = { .name = "mbox", };
515
516static int omap_mbox_register(struct omap_mbox_device *mdev)
517{
518	int ret;
519	int i;
520	struct omap_mbox **mboxes;
521
522	if (!mdev || !mdev->mboxes)
523		return -EINVAL;
524
525	mboxes = mdev->mboxes;
526	for (i = 0; mboxes[i]; i++) {
527		struct omap_mbox *mbox = mboxes[i];
 
528		mbox->dev = device_create(&omap_mbox_class, mdev->dev,
529					0, mbox, "%s", mbox->name);
530		if (IS_ERR(mbox->dev)) {
531			ret = PTR_ERR(mbox->dev);
532			goto err_out;
533		}
534	}
535
536	mutex_lock(&omap_mbox_devices_lock);
537	list_add(&mdev->elem, &omap_mbox_devices);
538	mutex_unlock(&omap_mbox_devices_lock);
539
540	ret = mbox_controller_register(&mdev->controller);
541
542err_out:
543	if (ret) {
544		while (i--)
545			device_unregister(mboxes[i]->dev);
546	}
547	return ret;
548}
549
550static int omap_mbox_unregister(struct omap_mbox_device *mdev)
551{
552	int i;
553	struct omap_mbox **mboxes;
554
555	if (!mdev || !mdev->mboxes)
556		return -EINVAL;
557
558	mutex_lock(&omap_mbox_devices_lock);
559	list_del(&mdev->elem);
560	mutex_unlock(&omap_mbox_devices_lock);
561
562	mbox_controller_unregister(&mdev->controller);
563
564	mboxes = mdev->mboxes;
565	for (i = 0; mboxes[i]; i++)
566		device_unregister(mboxes[i]->dev);
567	return 0;
568}
569
570static int omap_mbox_chan_startup(struct mbox_chan *chan)
571{
572	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
573	struct omap_mbox_device *mdev = mbox->parent;
574	int ret = 0;
575
576	mutex_lock(&mdev->cfg_lock);
577	pm_runtime_get_sync(mdev->dev);
578	ret = omap_mbox_startup(mbox);
579	if (ret)
580		pm_runtime_put_sync(mdev->dev);
581	mutex_unlock(&mdev->cfg_lock);
582	return ret;
583}
584
585static void omap_mbox_chan_shutdown(struct mbox_chan *chan)
586{
587	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
588	struct omap_mbox_device *mdev = mbox->parent;
589
590	mutex_lock(&mdev->cfg_lock);
591	omap_mbox_fini(mbox);
592	pm_runtime_put_sync(mdev->dev);
593	mutex_unlock(&mdev->cfg_lock);
594}
595
596static int omap_mbox_chan_send_noirq(struct omap_mbox *mbox, void *data)
597{
598	int ret = -EBUSY;
599
600	if (!mbox_fifo_full(mbox)) {
601		_omap_mbox_enable_irq(mbox, IRQ_RX);
602		mbox_fifo_write(mbox, (mbox_msg_t)data);
603		ret = 0;
604		_omap_mbox_disable_irq(mbox, IRQ_RX);
605
606		/* we must read and ack the interrupt directly from here */
607		mbox_fifo_read(mbox);
608		ack_mbox_irq(mbox, IRQ_RX);
609	}
610
611	return ret;
612}
613
614static int omap_mbox_chan_send(struct omap_mbox *mbox, void *data)
615{
616	int ret = -EBUSY;
617
618	if (!mbox_fifo_full(mbox)) {
619		mbox_fifo_write(mbox, (mbox_msg_t)data);
620		ret = 0;
621	}
622
623	/* always enable the interrupt */
624	_omap_mbox_enable_irq(mbox, IRQ_TX);
625	return ret;
626}
627
628static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data)
629{
630	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
631	int ret;
 
632
633	if (!mbox)
634		return -EINVAL;
635
636	if (mbox->send_no_irq)
637		ret = omap_mbox_chan_send_noirq(mbox, data);
638	else
639		ret = omap_mbox_chan_send(mbox, data);
640
641	return ret;
642}
643
644static const struct mbox_chan_ops omap_mbox_chan_ops = {
645	.startup        = omap_mbox_chan_startup,
646	.send_data      = omap_mbox_chan_send_data,
647	.shutdown       = omap_mbox_chan_shutdown,
648};
649
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
650static const struct of_device_id omap_mailbox_of_match[] = {
651	{
652		.compatible	= "ti,omap2-mailbox",
653		.data		= (void *)MBOX_INTR_CFG_TYPE1,
654	},
655	{
656		.compatible	= "ti,omap3-mailbox",
657		.data		= (void *)MBOX_INTR_CFG_TYPE1,
658	},
659	{
660		.compatible	= "ti,omap4-mailbox",
661		.data		= (void *)MBOX_INTR_CFG_TYPE2,
 
 
 
 
 
 
 
 
662	},
663	{
664		/* end */
665	},
666};
667MODULE_DEVICE_TABLE(of, omap_mailbox_of_match);
668
669static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
670					    const struct of_phandle_args *sp)
671{
672	phandle phandle = sp->args[0];
673	struct device_node *node;
674	struct omap_mbox_device *mdev;
675	struct omap_mbox *mbox;
676
677	mdev = container_of(controller, struct omap_mbox_device, controller);
678	if (WARN_ON(!mdev))
679		return ERR_PTR(-EINVAL);
680
681	node = of_find_node_by_phandle(phandle);
682	if (!node) {
683		pr_err("%s: could not find node phandle 0x%x\n",
684		       __func__, phandle);
685		return ERR_PTR(-ENODEV);
686	}
687
688	mbox = omap_mbox_device_find(mdev, node->name);
689	of_node_put(node);
690	return mbox ? mbox->chan : ERR_PTR(-ENOENT);
691}
692
693static int omap_mbox_probe(struct platform_device *pdev)
694{
695	struct resource *mem;
696	int ret;
697	struct mbox_chan *chnls;
698	struct omap_mbox **list, *mbox, *mboxblk;
699	struct omap_mbox_pdata *pdata = pdev->dev.platform_data;
700	struct omap_mbox_dev_info *info = NULL;
701	struct omap_mbox_fifo_info *finfo, *finfoblk;
702	struct omap_mbox_device *mdev;
703	struct omap_mbox_fifo *fifo;
704	struct device_node *node = pdev->dev.of_node;
705	struct device_node *child;
706	const struct of_device_id *match;
707	u32 intr_type, info_count;
708	u32 num_users, num_fifos;
709	u32 tmp[3];
710	u32 l;
711	int i;
712
713	if (!node && (!pdata || !pdata->info_cnt || !pdata->info)) {
714		pr_err("%s: platform not supported\n", __func__);
715		return -ENODEV;
716	}
717
718	if (node) {
719		match = of_match_device(omap_mailbox_of_match, &pdev->dev);
720		if (!match)
721			return -ENODEV;
722		intr_type = (u32)match->data;
723
724		if (of_property_read_u32(node, "ti,mbox-num-users",
725					 &num_users))
726			return -ENODEV;
727
728		if (of_property_read_u32(node, "ti,mbox-num-fifos",
729					 &num_fifos))
730			return -ENODEV;
731
732		info_count = of_get_available_child_count(node);
733		if (!info_count) {
734			dev_err(&pdev->dev, "no available mbox devices found\n");
735			return -ENODEV;
736		}
737	} else { /* non-DT device creation */
738		info_count = pdata->info_cnt;
739		info = pdata->info;
740		intr_type = pdata->intr_type;
741		num_users = pdata->num_users;
742		num_fifos = pdata->num_fifos;
743	}
744
745	finfoblk = devm_kzalloc(&pdev->dev, info_count * sizeof(*finfoblk),
746				GFP_KERNEL);
747	if (!finfoblk)
748		return -ENOMEM;
749
750	finfo = finfoblk;
751	child = NULL;
752	for (i = 0; i < info_count; i++, finfo++) {
753		if (node) {
754			child = of_get_next_available_child(node, child);
755			ret = of_property_read_u32_array(child, "ti,mbox-tx",
756							 tmp, ARRAY_SIZE(tmp));
757			if (ret)
758				return ret;
759			finfo->tx_id = tmp[0];
760			finfo->tx_irq = tmp[1];
761			finfo->tx_usr = tmp[2];
762
763			ret = of_property_read_u32_array(child, "ti,mbox-rx",
764							 tmp, ARRAY_SIZE(tmp));
765			if (ret)
766				return ret;
767			finfo->rx_id = tmp[0];
768			finfo->rx_irq = tmp[1];
769			finfo->rx_usr = tmp[2];
770
771			finfo->name = child->name;
772
773			if (of_find_property(child, "ti,mbox-send-noirq", NULL))
774				finfo->send_no_irq = true;
775		} else {
776			finfo->tx_id = info->tx_id;
777			finfo->rx_id = info->rx_id;
778			finfo->tx_usr = info->usr_id;
779			finfo->tx_irq = info->irq_id;
780			finfo->rx_usr = info->usr_id;
781			finfo->rx_irq = info->irq_id;
782			finfo->name = info->name;
783			info++;
784		}
785		if (finfo->tx_id >= num_fifos || finfo->rx_id >= num_fifos ||
786		    finfo->tx_usr >= num_users || finfo->rx_usr >= num_users)
787			return -EINVAL;
788	}
789
790	mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_KERNEL);
791	if (!mdev)
792		return -ENOMEM;
793
794	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
795	mdev->mbox_base = devm_ioremap_resource(&pdev->dev, mem);
796	if (IS_ERR(mdev->mbox_base))
797		return PTR_ERR(mdev->mbox_base);
798
 
 
 
 
 
799	/* allocate one extra for marking end of list */
800	list = devm_kzalloc(&pdev->dev, (info_count + 1) * sizeof(*list),
801			    GFP_KERNEL);
802	if (!list)
803		return -ENOMEM;
804
805	chnls = devm_kzalloc(&pdev->dev, (info_count + 1) * sizeof(*chnls),
806			     GFP_KERNEL);
807	if (!chnls)
808		return -ENOMEM;
809
810	mboxblk = devm_kzalloc(&pdev->dev, info_count * sizeof(*mbox),
811			       GFP_KERNEL);
812	if (!mboxblk)
813		return -ENOMEM;
814
815	mbox = mboxblk;
816	finfo = finfoblk;
817	for (i = 0; i < info_count; i++, finfo++) {
818		fifo = &mbox->tx_fifo;
819		fifo->msg = MAILBOX_MESSAGE(finfo->tx_id);
820		fifo->fifo_stat = MAILBOX_FIFOSTATUS(finfo->tx_id);
821		fifo->intr_bit = MAILBOX_IRQ_NOTFULL(finfo->tx_id);
822		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, finfo->tx_usr);
823		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, finfo->tx_usr);
824		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, finfo->tx_usr);
825
826		fifo = &mbox->rx_fifo;
827		fifo->msg = MAILBOX_MESSAGE(finfo->rx_id);
828		fifo->msg_stat =  MAILBOX_MSGSTATUS(finfo->rx_id);
829		fifo->intr_bit = MAILBOX_IRQ_NEWMSG(finfo->rx_id);
830		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, finfo->rx_usr);
831		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, finfo->rx_usr);
832		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, finfo->rx_usr);
833
834		mbox->send_no_irq = finfo->send_no_irq;
835		mbox->intr_type = intr_type;
836
837		mbox->parent = mdev;
838		mbox->name = finfo->name;
839		mbox->irq = platform_get_irq(pdev, finfo->tx_irq);
840		if (mbox->irq < 0)
841			return mbox->irq;
842		mbox->chan = &chnls[i];
843		chnls[i].con_priv = mbox;
844		list[i] = mbox++;
845	}
846
847	mutex_init(&mdev->cfg_lock);
848	mdev->dev = &pdev->dev;
849	mdev->num_users = num_users;
850	mdev->num_fifos = num_fifos;
 
851	mdev->mboxes = list;
852
853	/* OMAP does not have a Tx-Done IRQ, but rather a Tx-Ready IRQ */
 
 
 
854	mdev->controller.txdone_irq = true;
855	mdev->controller.dev = mdev->dev;
856	mdev->controller.ops = &omap_mbox_chan_ops;
857	mdev->controller.chans = chnls;
858	mdev->controller.num_chans = info_count;
859	mdev->controller.of_xlate = omap_mbox_of_xlate;
860	ret = omap_mbox_register(mdev);
861	if (ret)
862		return ret;
863
864	platform_set_drvdata(pdev, mdev);
865	pm_runtime_enable(mdev->dev);
866
867	ret = pm_runtime_get_sync(mdev->dev);
868	if (ret < 0) {
869		pm_runtime_put_noidle(mdev->dev);
870		goto unregister;
871	}
872
873	/*
874	 * just print the raw revision register, the format is not
875	 * uniform across all SoCs
876	 */
877	l = mbox_read_reg(mdev, MAILBOX_REVISION);
878	dev_info(mdev->dev, "omap mailbox rev 0x%x\n", l);
879
880	ret = pm_runtime_put_sync(mdev->dev);
881	if (ret < 0)
882		goto unregister;
883
884	devm_kfree(&pdev->dev, finfoblk);
885	return 0;
886
887unregister:
888	pm_runtime_disable(mdev->dev);
889	omap_mbox_unregister(mdev);
890	return ret;
891}
892
893static int omap_mbox_remove(struct platform_device *pdev)
894{
895	struct omap_mbox_device *mdev = platform_get_drvdata(pdev);
896
897	pm_runtime_disable(mdev->dev);
898	omap_mbox_unregister(mdev);
899
900	return 0;
901}
902
903static struct platform_driver omap_mbox_driver = {
904	.probe	= omap_mbox_probe,
905	.remove	= omap_mbox_remove,
906	.driver	= {
907		.name = "omap-mailbox",
 
908		.of_match_table = of_match_ptr(omap_mailbox_of_match),
909	},
910};
911
912static int __init omap_mbox_init(void)
913{
914	int err;
915
916	err = class_register(&omap_mbox_class);
917	if (err)
918		return err;
919
920	/* kfifo size sanity check: alignment and minimal size */
921	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
922	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
923							sizeof(mbox_msg_t));
 
 
 
924
925	return platform_driver_register(&omap_mbox_driver);
926}
927subsys_initcall(omap_mbox_init);
928
929static void __exit omap_mbox_exit(void)
930{
931	platform_driver_unregister(&omap_mbox_driver);
932	class_unregister(&omap_mbox_class);
933}
934module_exit(omap_mbox_exit);
935
936MODULE_LICENSE("GPL v2");
937MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
938MODULE_AUTHOR("Toshihiro Kobayashi");
939MODULE_AUTHOR("Hiroshi DOYU");