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v6.13.7
  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/io.h>
 19#include <linux/module.h>
 20#include <linux/of.h>
 21#include <linux/platform_device.h>
 22#include <linux/pm_runtime.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
 54typedef enum {
 55	IRQ_TX = 1,
 56	IRQ_RX = 2,
 57} omap_mbox_irq_t;
 58
 59struct omap_mbox_fifo {
 60	unsigned long msg;
 61	unsigned long fifo_stat;
 62	unsigned long msg_stat;
 63	unsigned long irqenable;
 64	unsigned long irqstatus;
 65	unsigned long irqdisable;
 66	u32 intr_bit;
 67};
 68
 69struct omap_mbox_match_data {
 70	u32 intr_type;
 
 
 
 
 71};
 72
 73struct omap_mbox_device {
 74	struct device *dev;
 75	struct mutex cfg_lock;
 76	void __iomem *mbox_base;
 77	u32 *irq_ctx;
 78	u32 num_users;
 79	u32 num_fifos;
 80	u32 intr_type;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 81};
 82
 83struct omap_mbox {
 84	const char		*name;
 85	int			irq;
 
 
 86	struct omap_mbox_device *parent;
 87	struct omap_mbox_fifo	tx_fifo;
 88	struct omap_mbox_fifo	rx_fifo;
 89	u32			intr_type;
 90	struct mbox_chan	*chan;
 91	bool			send_no_irq;
 92};
 93
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 94static inline
 95unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs)
 96{
 97	return __raw_readl(mdev->mbox_base + ofs);
 98}
 99
100static inline
101void mbox_write_reg(struct omap_mbox_device *mdev, u32 val, size_t ofs)
102{
103	__raw_writel(val, mdev->mbox_base + ofs);
104}
105
106/* Mailbox FIFO handle functions */
107static u32 mbox_fifo_read(struct omap_mbox *mbox)
108{
109	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
110
111	return mbox_read_reg(mbox->parent, fifo->msg);
112}
113
114static void mbox_fifo_write(struct omap_mbox *mbox, u32 msg)
115{
116	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
117
118	mbox_write_reg(mbox->parent, msg, fifo->msg);
119}
120
121static int mbox_fifo_empty(struct omap_mbox *mbox)
122{
123	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
124
125	return (mbox_read_reg(mbox->parent, fifo->msg_stat) == 0);
126}
127
128static int mbox_fifo_full(struct omap_mbox *mbox)
129{
130	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
131
132	return mbox_read_reg(mbox->parent, fifo->fifo_stat);
133}
134
135/* Mailbox IRQ handle functions */
136static void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
137{
138	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
139				&mbox->tx_fifo : &mbox->rx_fifo;
140	u32 bit = fifo->intr_bit;
141	u32 irqstatus = fifo->irqstatus;
142
143	mbox_write_reg(mbox->parent, bit, irqstatus);
144
145	/* Flush posted write for irq status to avoid spurious interrupts */
146	mbox_read_reg(mbox->parent, irqstatus);
147}
148
149static int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
150{
151	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
152				&mbox->tx_fifo : &mbox->rx_fifo;
153	u32 bit = fifo->intr_bit;
154	u32 irqenable = fifo->irqenable;
155	u32 irqstatus = fifo->irqstatus;
156
157	u32 enable = mbox_read_reg(mbox->parent, irqenable);
158	u32 status = mbox_read_reg(mbox->parent, irqstatus);
159
160	return (int)(enable & status & bit);
161}
162
163static void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
164{
165	u32 l;
166	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
167				&mbox->tx_fifo : &mbox->rx_fifo;
168	u32 bit = fifo->intr_bit;
169	u32 irqenable = fifo->irqenable;
170
171	l = mbox_read_reg(mbox->parent, irqenable);
172	l |= bit;
173	mbox_write_reg(mbox->parent, l, irqenable);
174}
175
176static void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
177{
178	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
179				&mbox->tx_fifo : &mbox->rx_fifo;
180	u32 bit = fifo->intr_bit;
181	u32 irqdisable = fifo->irqdisable;
182
183	/*
184	 * Read and update the interrupt configuration register for pre-OMAP4.
185	 * OMAP4 and later SoCs have a dedicated interrupt disabling register.
186	 */
187	if (!mbox->intr_type)
188		bit = mbox_read_reg(mbox->parent, irqdisable) & ~bit;
189
190	mbox_write_reg(mbox->parent, bit, irqdisable);
191}
192
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
193/*
194 * Mailbox interrupt handler
195 */
196static void __mbox_tx_interrupt(struct omap_mbox *mbox)
197{
198	omap_mbox_disable_irq(mbox, IRQ_TX);
199	ack_mbox_irq(mbox, IRQ_TX);
200	mbox_chan_txdone(mbox->chan, 0);
201}
202
203static void __mbox_rx_interrupt(struct omap_mbox *mbox)
204{
205	u32 msg;
 
 
206
207	while (!mbox_fifo_empty(mbox)) {
 
 
 
 
 
 
208		msg = mbox_fifo_read(mbox);
209		mbox_chan_received_data(mbox->chan, (void *)(uintptr_t)msg);
 
 
210	}
211
212	/* clear IRQ source. */
213	ack_mbox_irq(mbox, IRQ_RX);
 
 
214}
215
216static irqreturn_t mbox_interrupt(int irq, void *p)
217{
218	struct omap_mbox *mbox = p;
219
220	if (is_mbox_irq(mbox, IRQ_TX))
221		__mbox_tx_interrupt(mbox);
222
223	if (is_mbox_irq(mbox, IRQ_RX))
224		__mbox_rx_interrupt(mbox);
225
226	return IRQ_HANDLED;
227}
228
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
229static int omap_mbox_startup(struct omap_mbox *mbox)
230{
231	int ret = 0;
 
232
233	ret = request_threaded_irq(mbox->irq, NULL, mbox_interrupt,
234				   IRQF_SHARED | IRQF_ONESHOT, mbox->name,
235				   mbox);
 
 
 
 
 
236	if (unlikely(ret)) {
237		pr_err("failed to register mailbox interrupt:%d\n", ret);
238		return ret;
239	}
240
241	if (mbox->send_no_irq)
242		mbox->chan->txdone_method = TXDONE_BY_ACK;
243
244	omap_mbox_enable_irq(mbox, IRQ_RX);
245
246	return 0;
 
 
 
 
247}
248
249static void omap_mbox_fini(struct omap_mbox *mbox)
250{
251	omap_mbox_disable_irq(mbox, IRQ_RX);
252	free_irq(mbox->irq, mbox);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
253}
254
255static int omap_mbox_chan_startup(struct mbox_chan *chan)
256{
257	struct omap_mbox *mbox = chan->con_priv;
258	struct omap_mbox_device *mdev = mbox->parent;
259	int ret = 0;
260
261	mutex_lock(&mdev->cfg_lock);
262	pm_runtime_get_sync(mdev->dev);
263	ret = omap_mbox_startup(mbox);
264	if (ret)
265		pm_runtime_put_sync(mdev->dev);
266	mutex_unlock(&mdev->cfg_lock);
267	return ret;
268}
269
270static void omap_mbox_chan_shutdown(struct mbox_chan *chan)
271{
272	struct omap_mbox *mbox = chan->con_priv;
273	struct omap_mbox_device *mdev = mbox->parent;
274
275	mutex_lock(&mdev->cfg_lock);
276	omap_mbox_fini(mbox);
277	pm_runtime_put_sync(mdev->dev);
278	mutex_unlock(&mdev->cfg_lock);
279}
280
281static int omap_mbox_chan_send_noirq(struct omap_mbox *mbox, u32 msg)
282{
283	if (mbox_fifo_full(mbox))
284		return -EBUSY;
285
286	omap_mbox_enable_irq(mbox, IRQ_RX);
287	mbox_fifo_write(mbox, msg);
288	omap_mbox_disable_irq(mbox, IRQ_RX);
289
290	/* we must read and ack the interrupt directly from here */
291	mbox_fifo_read(mbox);
292	ack_mbox_irq(mbox, IRQ_RX);
 
 
 
 
 
 
 
293
294	return 0;
295}
296
297static int omap_mbox_chan_send(struct omap_mbox *mbox, u32 msg)
298{
299	if (mbox_fifo_full(mbox)) {
300		/* always enable the interrupt */
301		omap_mbox_enable_irq(mbox, IRQ_TX);
302		return -EBUSY;
303	}
304
305	mbox_fifo_write(mbox, msg);
 
 
 
306
307	/* always enable the interrupt */
308	omap_mbox_enable_irq(mbox, IRQ_TX);
309	return 0;
310}
311
312static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data)
313{
314	struct omap_mbox *mbox = chan->con_priv;
315	int ret;
316	u32 msg = (u32)(uintptr_t)(data);
317
318	if (!mbox)
319		return -EINVAL;
320
321	if (mbox->send_no_irq)
322		ret = omap_mbox_chan_send_noirq(mbox, msg);
323	else
324		ret = omap_mbox_chan_send(mbox, msg);
325
326	return ret;
327}
328
329static const struct mbox_chan_ops omap_mbox_chan_ops = {
330	.startup        = omap_mbox_chan_startup,
331	.send_data      = omap_mbox_chan_send_data,
332	.shutdown       = omap_mbox_chan_shutdown,
333};
334
335#ifdef CONFIG_PM_SLEEP
336static int omap_mbox_suspend(struct device *dev)
337{
338	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
339	u32 usr, fifo, reg;
340
341	if (pm_runtime_status_suspended(dev))
342		return 0;
343
344	for (fifo = 0; fifo < mdev->num_fifos; fifo++) {
345		if (mbox_read_reg(mdev, MAILBOX_MSGSTATUS(fifo))) {
346			dev_err(mdev->dev, "fifo %d has unexpected unread messages\n",
347				fifo);
348			return -EBUSY;
349		}
350	}
351
352	for (usr = 0; usr < mdev->num_users; usr++) {
353		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
354		mdev->irq_ctx[usr] = mbox_read_reg(mdev, reg);
355	}
356
357	return 0;
358}
359
360static int omap_mbox_resume(struct device *dev)
361{
362	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
363	u32 usr, reg;
364
365	if (pm_runtime_status_suspended(dev))
366		return 0;
367
368	for (usr = 0; usr < mdev->num_users; usr++) {
369		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
370		mbox_write_reg(mdev, mdev->irq_ctx[usr], reg);
371	}
372
373	return 0;
374}
375#endif
376
377static const struct dev_pm_ops omap_mbox_pm_ops = {
378	SET_SYSTEM_SLEEP_PM_OPS(omap_mbox_suspend, omap_mbox_resume)
379};
380
381static const struct omap_mbox_match_data omap2_data = { MBOX_INTR_CFG_TYPE1 };
382static const struct omap_mbox_match_data omap4_data = { MBOX_INTR_CFG_TYPE2 };
383
384static const struct of_device_id omap_mailbox_of_match[] = {
385	{
386		.compatible	= "ti,omap2-mailbox",
387		.data		= &omap2_data,
388	},
389	{
390		.compatible	= "ti,omap3-mailbox",
391		.data		= &omap2_data,
392	},
393	{
394		.compatible	= "ti,omap4-mailbox",
395		.data		= &omap4_data,
396	},
397	{
398		.compatible	= "ti,am654-mailbox",
399		.data		= &omap4_data,
400	},
401	{
402		.compatible	= "ti,am64-mailbox",
403		.data		= &omap4_data,
404	},
405	{
406		/* end */
407	},
408};
409MODULE_DEVICE_TABLE(of, omap_mailbox_of_match);
410
411static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
412					    const struct of_phandle_args *sp)
413{
414	phandle phandle = sp->args[0];
415	struct device_node *node;
416	struct omap_mbox_device *mdev;
417	struct omap_mbox *mbox;
418	int i;
419
420	mdev = dev_get_drvdata(controller->dev);
421	if (WARN_ON(!mdev))
422		return ERR_PTR(-EINVAL);
423
424	node = of_find_node_by_phandle(phandle);
425	if (!node) {
426		pr_err("%s: could not find node phandle 0x%x\n",
427		       __func__, phandle);
428		return ERR_PTR(-ENODEV);
429	}
430
431	for (i = 0; i < controller->num_chans; i++) {
432		mbox = controller->chans[i].con_priv;
433		if (!strcmp(mbox->name, node->name)) {
434			of_node_put(node);
435			return &controller->chans[i];
436		}
437	}
438
439	of_node_put(node);
440	return ERR_PTR(-ENOENT);
441}
442
443static int omap_mbox_probe(struct platform_device *pdev)
444{
 
445	int ret;
446	struct mbox_chan *chnls;
447	struct omap_mbox *mbox;
 
448	struct omap_mbox_device *mdev;
449	struct omap_mbox_fifo *fifo;
450	struct device_node *node = pdev->dev.of_node;
451	struct device_node *child;
452	const struct omap_mbox_match_data *match_data;
453	struct mbox_controller *controller;
454	u32 intr_type, info_count;
455	u32 num_users, num_fifos;
456	u32 tmp[3];
457	u32 l;
458	int i;
459
460	if (!node) {
461		pr_err("%s: only DT-based devices are supported\n", __func__);
462		return -ENODEV;
463	}
464
465	match_data = of_device_get_match_data(&pdev->dev);
466	if (!match_data)
467		return -ENODEV;
468	intr_type = match_data->intr_type;
469
470	if (of_property_read_u32(node, "ti,mbox-num-users", &num_users))
471		return -ENODEV;
472
473	if (of_property_read_u32(node, "ti,mbox-num-fifos", &num_fifos))
474		return -ENODEV;
475
476	info_count = of_get_available_child_count(node);
477	if (!info_count) {
478		dev_err(&pdev->dev, "no available mbox devices found\n");
479		return -ENODEV;
480	}
481
482	mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_KERNEL);
483	if (!mdev)
484		return -ENOMEM;
485
486	mdev->mbox_base = devm_platform_ioremap_resource(pdev, 0);
487	if (IS_ERR(mdev->mbox_base))
488		return PTR_ERR(mdev->mbox_base);
489
490	mdev->irq_ctx = devm_kcalloc(&pdev->dev, num_users, sizeof(u32),
491				     GFP_KERNEL);
492	if (!mdev->irq_ctx)
493		return -ENOMEM;
494
495	chnls = devm_kcalloc(&pdev->dev, info_count + 1, sizeof(*chnls),
496			     GFP_KERNEL);
497	if (!chnls)
498		return -ENOMEM;
499
 
500	child = NULL;
501	for (i = 0; i < info_count; i++) {
502		int tx_id, tx_irq, tx_usr;
503		int rx_id,         rx_usr;
504
505		mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), GFP_KERNEL);
506		if (!mbox)
507			return -ENOMEM;
508
509		child = of_get_next_available_child(node, child);
510		ret = of_property_read_u32_array(child, "ti,mbox-tx", tmp,
511						 ARRAY_SIZE(tmp));
512		if (ret)
513			return ret;
514		tx_id = tmp[0];
515		tx_irq = tmp[1];
516		tx_usr = tmp[2];
517
518		ret = of_property_read_u32_array(child, "ti,mbox-rx", tmp,
519						 ARRAY_SIZE(tmp));
520		if (ret)
521			return ret;
522		rx_id = tmp[0];
523		/* rx_irq = tmp[1]; */
524		rx_usr = tmp[2];
 
 
525
526		if (tx_id >= num_fifos || rx_id >= num_fifos ||
527		    tx_usr >= num_users || rx_usr >= num_users)
 
 
 
528			return -EINVAL;
 
529
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
530		fifo = &mbox->tx_fifo;
531		fifo->msg = MAILBOX_MESSAGE(tx_id);
532		fifo->fifo_stat = MAILBOX_FIFOSTATUS(tx_id);
533		fifo->intr_bit = MAILBOX_IRQ_NOTFULL(tx_id);
534		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, tx_usr);
535		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, tx_usr);
536		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, tx_usr);
537
538		fifo = &mbox->rx_fifo;
539		fifo->msg = MAILBOX_MESSAGE(rx_id);
540		fifo->msg_stat =  MAILBOX_MSGSTATUS(rx_id);
541		fifo->intr_bit = MAILBOX_IRQ_NEWMSG(rx_id);
542		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, rx_usr);
543		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, rx_usr);
544		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, rx_usr);
545
546		mbox->send_no_irq = of_property_read_bool(child, "ti,mbox-send-noirq");
547		mbox->intr_type = intr_type;
548
549		mbox->parent = mdev;
550		mbox->name = child->name;
551		mbox->irq = platform_get_irq(pdev, tx_irq);
552		if (mbox->irq < 0)
553			return mbox->irq;
554		mbox->chan = &chnls[i];
555		chnls[i].con_priv = mbox;
 
556	}
557
558	mutex_init(&mdev->cfg_lock);
559	mdev->dev = &pdev->dev;
560	mdev->num_users = num_users;
561	mdev->num_fifos = num_fifos;
562	mdev->intr_type = intr_type;
 
563
564	controller = devm_kzalloc(&pdev->dev, sizeof(*controller), GFP_KERNEL);
565	if (!controller)
566		return -ENOMEM;
567	/*
568	 * OMAP/K3 Mailbox IP does not have a Tx-Done IRQ, but rather a Tx-Ready
569	 * IRQ and is needed to run the Tx state machine
570	 */
571	controller->txdone_irq = true;
572	controller->dev = mdev->dev;
573	controller->ops = &omap_mbox_chan_ops;
574	controller->chans = chnls;
575	controller->num_chans = info_count;
576	controller->of_xlate = omap_mbox_of_xlate;
577	ret = devm_mbox_controller_register(mdev->dev, controller);
578	if (ret)
579		return ret;
580
581	platform_set_drvdata(pdev, mdev);
582	devm_pm_runtime_enable(mdev->dev);
583
584	ret = pm_runtime_resume_and_get(mdev->dev);
585	if (ret < 0)
586		return ret;
 
 
587
588	/*
589	 * just print the raw revision register, the format is not
590	 * uniform across all SoCs
591	 */
592	l = mbox_read_reg(mdev, MAILBOX_REVISION);
593	dev_info(mdev->dev, "omap mailbox rev 0x%x\n", l);
594
595	ret = pm_runtime_put_sync(mdev->dev);
596	if (ret < 0 && ret != -ENOSYS)
597		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
598
599	return 0;
600}
601
602static struct platform_driver omap_mbox_driver = {
603	.probe	= omap_mbox_probe,
 
604	.driver	= {
605		.name = "omap-mailbox",
606		.pm = &omap_mbox_pm_ops,
607		.of_match_table = omap_mailbox_of_match,
608	},
609};
610module_platform_driver(omap_mbox_driver);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
611
612MODULE_LICENSE("GPL v2");
613MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
614MODULE_AUTHOR("Toshihiro Kobayashi");
615MODULE_AUTHOR("Hiroshi DOYU");
v4.10.11
 
  1/*
  2 * OMAP mailbox driver
  3 *
  4 * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
  5 * Copyright (C) 2013-2016 Texas Instruments Incorporated - http://www.ti.com
  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
 20#include <linux/interrupt.h>
 21#include <linux/spinlock.h>
 22#include <linux/mutex.h>
 23#include <linux/slab.h>
 24#include <linux/kfifo.h>
 25#include <linux/err.h>
 
 26#include <linux/module.h>
 27#include <linux/of_device.h>
 28#include <linux/platform_device.h>
 29#include <linux/pm_runtime.h>
 30#include <linux/omap-mailbox.h>
 31#include <linux/mailbox_controller.h>
 32#include <linux/mailbox_client.h>
 33
 34#include "mailbox.h"
 35
 36#define MAILBOX_REVISION		0x000
 37#define MAILBOX_MESSAGE(m)		(0x040 + 4 * (m))
 38#define MAILBOX_FIFOSTATUS(m)		(0x080 + 4 * (m))
 39#define MAILBOX_MSGSTATUS(m)		(0x0c0 + 4 * (m))
 40
 41#define OMAP2_MAILBOX_IRQSTATUS(u)	(0x100 + 8 * (u))
 42#define OMAP2_MAILBOX_IRQENABLE(u)	(0x104 + 8 * (u))
 43
 44#define OMAP4_MAILBOX_IRQSTATUS(u)	(0x104 + 0x10 * (u))
 45#define OMAP4_MAILBOX_IRQENABLE(u)	(0x108 + 0x10 * (u))
 46#define OMAP4_MAILBOX_IRQENABLE_CLR(u)	(0x10c + 0x10 * (u))
 47
 48#define MAILBOX_IRQSTATUS(type, u)	(type ? OMAP4_MAILBOX_IRQSTATUS(u) : \
 49						OMAP2_MAILBOX_IRQSTATUS(u))
 50#define MAILBOX_IRQENABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE(u) : \
 51						OMAP2_MAILBOX_IRQENABLE(u))
 52#define MAILBOX_IRQDISABLE(type, u)	(type ? OMAP4_MAILBOX_IRQENABLE_CLR(u) \
 53						: OMAP2_MAILBOX_IRQENABLE(u))
 54
 55#define MAILBOX_IRQ_NEWMSG(m)		(1 << (2 * (m)))
 56#define MAILBOX_IRQ_NOTFULL(m)		(1 << (2 * (m) + 1))
 57
 58/* Interrupt register configuration types */
 59#define MBOX_INTR_CFG_TYPE1		0
 60#define MBOX_INTR_CFG_TYPE2		1
 61
 
 
 
 
 
 62struct omap_mbox_fifo {
 63	unsigned long msg;
 64	unsigned long fifo_stat;
 65	unsigned long msg_stat;
 66	unsigned long irqenable;
 67	unsigned long irqstatus;
 68	unsigned long irqdisable;
 69	u32 intr_bit;
 70};
 71
 72struct omap_mbox_queue {
 73	spinlock_t		lock;
 74	struct kfifo		fifo;
 75	struct work_struct	work;
 76	struct omap_mbox	*mbox;
 77	bool full;
 78};
 79
 80struct omap_mbox_device {
 81	struct device *dev;
 82	struct mutex cfg_lock;
 83	void __iomem *mbox_base;
 84	u32 *irq_ctx;
 85	u32 num_users;
 86	u32 num_fifos;
 87	u32 intr_type;
 88	struct omap_mbox **mboxes;
 89	struct mbox_controller controller;
 90	struct list_head elem;
 91};
 92
 93struct omap_mbox_fifo_info {
 94	int tx_id;
 95	int tx_usr;
 96	int tx_irq;
 97
 98	int rx_id;
 99	int rx_usr;
100	int rx_irq;
101
102	const char *name;
103	bool send_no_irq;
104};
105
106struct omap_mbox {
107	const char		*name;
108	int			irq;
109	struct omap_mbox_queue	*rxq;
110	struct device		*dev;
111	struct omap_mbox_device *parent;
112	struct omap_mbox_fifo	tx_fifo;
113	struct omap_mbox_fifo	rx_fifo;
114	u32			intr_type;
115	struct mbox_chan	*chan;
116	bool			send_no_irq;
117};
118
119/* global variables for the mailbox devices */
120static DEFINE_MUTEX(omap_mbox_devices_lock);
121static LIST_HEAD(omap_mbox_devices);
122
123static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
124module_param(mbox_kfifo_size, uint, S_IRUGO);
125MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
126
127static struct omap_mbox *mbox_chan_to_omap_mbox(struct mbox_chan *chan)
128{
129	if (!chan || !chan->con_priv)
130		return NULL;
131
132	return (struct omap_mbox *)chan->con_priv;
133}
134
135static inline
136unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs)
137{
138	return __raw_readl(mdev->mbox_base + ofs);
139}
140
141static inline
142void mbox_write_reg(struct omap_mbox_device *mdev, u32 val, size_t ofs)
143{
144	__raw_writel(val, mdev->mbox_base + ofs);
145}
146
147/* Mailbox FIFO handle functions */
148static mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
149{
150	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
151
152	return (mbox_msg_t)mbox_read_reg(mbox->parent, fifo->msg);
153}
154
155static void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
156{
157	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
158
159	mbox_write_reg(mbox->parent, msg, fifo->msg);
160}
161
162static int mbox_fifo_empty(struct omap_mbox *mbox)
163{
164	struct omap_mbox_fifo *fifo = &mbox->rx_fifo;
165
166	return (mbox_read_reg(mbox->parent, fifo->msg_stat) == 0);
167}
168
169static int mbox_fifo_full(struct omap_mbox *mbox)
170{
171	struct omap_mbox_fifo *fifo = &mbox->tx_fifo;
172
173	return mbox_read_reg(mbox->parent, fifo->fifo_stat);
174}
175
176/* Mailbox IRQ handle functions */
177static void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
178{
179	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
180				&mbox->tx_fifo : &mbox->rx_fifo;
181	u32 bit = fifo->intr_bit;
182	u32 irqstatus = fifo->irqstatus;
183
184	mbox_write_reg(mbox->parent, bit, irqstatus);
185
186	/* Flush posted write for irq status to avoid spurious interrupts */
187	mbox_read_reg(mbox->parent, irqstatus);
188}
189
190static int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
191{
192	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
193				&mbox->tx_fifo : &mbox->rx_fifo;
194	u32 bit = fifo->intr_bit;
195	u32 irqenable = fifo->irqenable;
196	u32 irqstatus = fifo->irqstatus;
197
198	u32 enable = mbox_read_reg(mbox->parent, irqenable);
199	u32 status = mbox_read_reg(mbox->parent, irqstatus);
200
201	return (int)(enable & status & bit);
202}
203
204static void _omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
205{
206	u32 l;
207	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
208				&mbox->tx_fifo : &mbox->rx_fifo;
209	u32 bit = fifo->intr_bit;
210	u32 irqenable = fifo->irqenable;
211
212	l = mbox_read_reg(mbox->parent, irqenable);
213	l |= bit;
214	mbox_write_reg(mbox->parent, l, irqenable);
215}
216
217static void _omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
218{
219	struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
220				&mbox->tx_fifo : &mbox->rx_fifo;
221	u32 bit = fifo->intr_bit;
222	u32 irqdisable = fifo->irqdisable;
223
224	/*
225	 * Read and update the interrupt configuration register for pre-OMAP4.
226	 * OMAP4 and later SoCs have a dedicated interrupt disabling register.
227	 */
228	if (!mbox->intr_type)
229		bit = mbox_read_reg(mbox->parent, irqdisable) & ~bit;
230
231	mbox_write_reg(mbox->parent, bit, irqdisable);
232}
233
234void omap_mbox_enable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
235{
236	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
237
238	if (WARN_ON(!mbox))
239		return;
240
241	_omap_mbox_enable_irq(mbox, irq);
242}
243EXPORT_SYMBOL(omap_mbox_enable_irq);
244
245void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
246{
247	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
248
249	if (WARN_ON(!mbox))
250		return;
251
252	_omap_mbox_disable_irq(mbox, irq);
253}
254EXPORT_SYMBOL(omap_mbox_disable_irq);
255
256/*
257 * Message receiver(workqueue)
258 */
259static void mbox_rx_work(struct work_struct *work)
260{
261	struct omap_mbox_queue *mq =
262			container_of(work, struct omap_mbox_queue, work);
263	mbox_msg_t msg;
264	int len;
265
266	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
267		len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
268		WARN_ON(len != sizeof(msg));
269
270		mbox_chan_received_data(mq->mbox->chan, (void *)msg);
271		spin_lock_irq(&mq->lock);
272		if (mq->full) {
273			mq->full = false;
274			_omap_mbox_enable_irq(mq->mbox, IRQ_RX);
275		}
276		spin_unlock_irq(&mq->lock);
277	}
278}
279
280/*
281 * Mailbox interrupt handler
282 */
283static void __mbox_tx_interrupt(struct omap_mbox *mbox)
284{
285	_omap_mbox_disable_irq(mbox, IRQ_TX);
286	ack_mbox_irq(mbox, IRQ_TX);
287	mbox_chan_txdone(mbox->chan, 0);
288}
289
290static void __mbox_rx_interrupt(struct omap_mbox *mbox)
291{
292	struct omap_mbox_queue *mq = mbox->rxq;
293	mbox_msg_t msg;
294	int len;
295
296	while (!mbox_fifo_empty(mbox)) {
297		if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
298			_omap_mbox_disable_irq(mbox, IRQ_RX);
299			mq->full = true;
300			goto nomem;
301		}
302
303		msg = mbox_fifo_read(mbox);
304
305		len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
306		WARN_ON(len != sizeof(msg));
307	}
308
309	/* no more messages in the fifo. clear IRQ source. */
310	ack_mbox_irq(mbox, IRQ_RX);
311nomem:
312	schedule_work(&mbox->rxq->work);
313}
314
315static irqreturn_t mbox_interrupt(int irq, void *p)
316{
317	struct omap_mbox *mbox = p;
318
319	if (is_mbox_irq(mbox, IRQ_TX))
320		__mbox_tx_interrupt(mbox);
321
322	if (is_mbox_irq(mbox, IRQ_RX))
323		__mbox_rx_interrupt(mbox);
324
325	return IRQ_HANDLED;
326}
327
328static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
329					void (*work)(struct work_struct *))
330{
331	struct omap_mbox_queue *mq;
332
333	if (!work)
334		return NULL;
335
336	mq = kzalloc(sizeof(*mq), GFP_KERNEL);
337	if (!mq)
338		return NULL;
339
340	spin_lock_init(&mq->lock);
341
342	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
343		goto error;
344
345	INIT_WORK(&mq->work, work);
346	return mq;
347
348error:
349	kfree(mq);
350	return NULL;
351}
352
353static void mbox_queue_free(struct omap_mbox_queue *q)
354{
355	kfifo_free(&q->fifo);
356	kfree(q);
357}
358
359static int omap_mbox_startup(struct omap_mbox *mbox)
360{
361	int ret = 0;
362	struct omap_mbox_queue *mq;
363
364	mq = mbox_queue_alloc(mbox, mbox_rx_work);
365	if (!mq)
366		return -ENOMEM;
367	mbox->rxq = mq;
368	mq->mbox = mbox;
369
370	ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
371			  mbox->name, mbox);
372	if (unlikely(ret)) {
373		pr_err("failed to register mailbox interrupt:%d\n", ret);
374		goto fail_request_irq;
375	}
376
377	if (mbox->send_no_irq)
378		mbox->chan->txdone_method = TXDONE_BY_ACK;
379
380	_omap_mbox_enable_irq(mbox, IRQ_RX);
381
382	return 0;
383
384fail_request_irq:
385	mbox_queue_free(mbox->rxq);
386	return ret;
387}
388
389static void omap_mbox_fini(struct omap_mbox *mbox)
390{
391	_omap_mbox_disable_irq(mbox, IRQ_RX);
392	free_irq(mbox->irq, mbox);
393	flush_work(&mbox->rxq->work);
394	mbox_queue_free(mbox->rxq);
395}
396
397static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev,
398					       const char *mbox_name)
399{
400	struct omap_mbox *_mbox, *mbox = NULL;
401	struct omap_mbox **mboxes = mdev->mboxes;
402	int i;
403
404	if (!mboxes)
405		return NULL;
406
407	for (i = 0; (_mbox = mboxes[i]); i++) {
408		if (!strcmp(_mbox->name, mbox_name)) {
409			mbox = _mbox;
410			break;
411		}
412	}
413	return mbox;
414}
415
416struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl,
417					    const char *chan_name)
418{
419	struct device *dev = cl->dev;
420	struct omap_mbox *mbox = NULL;
421	struct omap_mbox_device *mdev;
422	struct mbox_chan *chan;
423	unsigned long flags;
424	int ret;
425
426	if (!dev)
427		return ERR_PTR(-ENODEV);
428
429	if (dev->of_node) {
430		pr_err("%s: please use mbox_request_channel(), this API is supported only for OMAP non-DT usage\n",
431		       __func__);
432		return ERR_PTR(-ENODEV);
433	}
434
435	mutex_lock(&omap_mbox_devices_lock);
436	list_for_each_entry(mdev, &omap_mbox_devices, elem) {
437		mbox = omap_mbox_device_find(mdev, chan_name);
438		if (mbox)
439			break;
440	}
441	mutex_unlock(&omap_mbox_devices_lock);
442
443	if (!mbox || !mbox->chan)
444		return ERR_PTR(-ENOENT);
445
446	chan = mbox->chan;
447	spin_lock_irqsave(&chan->lock, flags);
448	chan->msg_free = 0;
449	chan->msg_count = 0;
450	chan->active_req = NULL;
451	chan->cl = cl;
452	init_completion(&chan->tx_complete);
453	spin_unlock_irqrestore(&chan->lock, flags);
454
455	ret = chan->mbox->ops->startup(chan);
456	if (ret) {
457		pr_err("Unable to startup the chan (%d)\n", ret);
458		mbox_free_channel(chan);
459		chan = ERR_PTR(ret);
460	}
461
462	return chan;
463}
464EXPORT_SYMBOL(omap_mbox_request_channel);
465
466static struct class omap_mbox_class = { .name = "mbox", };
467
468static int omap_mbox_register(struct omap_mbox_device *mdev)
469{
470	int ret;
471	int i;
472	struct omap_mbox **mboxes;
473
474	if (!mdev || !mdev->mboxes)
475		return -EINVAL;
476
477	mboxes = mdev->mboxes;
478	for (i = 0; mboxes[i]; i++) {
479		struct omap_mbox *mbox = mboxes[i];
480
481		mbox->dev = device_create(&omap_mbox_class, mdev->dev,
482					0, mbox, "%s", mbox->name);
483		if (IS_ERR(mbox->dev)) {
484			ret = PTR_ERR(mbox->dev);
485			goto err_out;
486		}
487	}
488
489	mutex_lock(&omap_mbox_devices_lock);
490	list_add(&mdev->elem, &omap_mbox_devices);
491	mutex_unlock(&omap_mbox_devices_lock);
492
493	ret = mbox_controller_register(&mdev->controller);
494
495err_out:
496	if (ret) {
497		while (i--)
498			device_unregister(mboxes[i]->dev);
499	}
500	return ret;
501}
502
503static int omap_mbox_unregister(struct omap_mbox_device *mdev)
504{
505	int i;
506	struct omap_mbox **mboxes;
507
508	if (!mdev || !mdev->mboxes)
509		return -EINVAL;
510
511	mutex_lock(&omap_mbox_devices_lock);
512	list_del(&mdev->elem);
513	mutex_unlock(&omap_mbox_devices_lock);
514
515	mbox_controller_unregister(&mdev->controller);
516
517	mboxes = mdev->mboxes;
518	for (i = 0; mboxes[i]; i++)
519		device_unregister(mboxes[i]->dev);
520	return 0;
521}
522
523static int omap_mbox_chan_startup(struct mbox_chan *chan)
524{
525	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
526	struct omap_mbox_device *mdev = mbox->parent;
527	int ret = 0;
528
529	mutex_lock(&mdev->cfg_lock);
530	pm_runtime_get_sync(mdev->dev);
531	ret = omap_mbox_startup(mbox);
532	if (ret)
533		pm_runtime_put_sync(mdev->dev);
534	mutex_unlock(&mdev->cfg_lock);
535	return ret;
536}
537
538static void omap_mbox_chan_shutdown(struct mbox_chan *chan)
539{
540	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
541	struct omap_mbox_device *mdev = mbox->parent;
542
543	mutex_lock(&mdev->cfg_lock);
544	omap_mbox_fini(mbox);
545	pm_runtime_put_sync(mdev->dev);
546	mutex_unlock(&mdev->cfg_lock);
547}
548
549static int omap_mbox_chan_send_noirq(struct omap_mbox *mbox, void *data)
550{
551	int ret = -EBUSY;
 
 
 
 
 
552
553	if (!mbox_fifo_full(mbox)) {
554		_omap_mbox_enable_irq(mbox, IRQ_RX);
555		mbox_fifo_write(mbox, (mbox_msg_t)data);
556		ret = 0;
557		_omap_mbox_disable_irq(mbox, IRQ_RX);
558
559		/* we must read and ack the interrupt directly from here */
560		mbox_fifo_read(mbox);
561		ack_mbox_irq(mbox, IRQ_RX);
562	}
563
564	return ret;
565}
566
567static int omap_mbox_chan_send(struct omap_mbox *mbox, void *data)
568{
569	int ret = -EBUSY;
 
 
 
 
570
571	if (!mbox_fifo_full(mbox)) {
572		mbox_fifo_write(mbox, (mbox_msg_t)data);
573		ret = 0;
574	}
575
576	/* always enable the interrupt */
577	_omap_mbox_enable_irq(mbox, IRQ_TX);
578	return ret;
579}
580
581static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data)
582{
583	struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
584	int ret;
 
585
586	if (!mbox)
587		return -EINVAL;
588
589	if (mbox->send_no_irq)
590		ret = omap_mbox_chan_send_noirq(mbox, data);
591	else
592		ret = omap_mbox_chan_send(mbox, data);
593
594	return ret;
595}
596
597static const struct mbox_chan_ops omap_mbox_chan_ops = {
598	.startup        = omap_mbox_chan_startup,
599	.send_data      = omap_mbox_chan_send_data,
600	.shutdown       = omap_mbox_chan_shutdown,
601};
602
603#ifdef CONFIG_PM_SLEEP
604static int omap_mbox_suspend(struct device *dev)
605{
606	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
607	u32 usr, fifo, reg;
608
609	if (pm_runtime_status_suspended(dev))
610		return 0;
611
612	for (fifo = 0; fifo < mdev->num_fifos; fifo++) {
613		if (mbox_read_reg(mdev, MAILBOX_MSGSTATUS(fifo))) {
614			dev_err(mdev->dev, "fifo %d has unexpected unread messages\n",
615				fifo);
616			return -EBUSY;
617		}
618	}
619
620	for (usr = 0; usr < mdev->num_users; usr++) {
621		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
622		mdev->irq_ctx[usr] = mbox_read_reg(mdev, reg);
623	}
624
625	return 0;
626}
627
628static int omap_mbox_resume(struct device *dev)
629{
630	struct omap_mbox_device *mdev = dev_get_drvdata(dev);
631	u32 usr, reg;
632
633	if (pm_runtime_status_suspended(dev))
634		return 0;
635
636	for (usr = 0; usr < mdev->num_users; usr++) {
637		reg = MAILBOX_IRQENABLE(mdev->intr_type, usr);
638		mbox_write_reg(mdev, mdev->irq_ctx[usr], reg);
639	}
640
641	return 0;
642}
643#endif
644
645static const struct dev_pm_ops omap_mbox_pm_ops = {
646	SET_SYSTEM_SLEEP_PM_OPS(omap_mbox_suspend, omap_mbox_resume)
647};
648
 
 
 
649static const struct of_device_id omap_mailbox_of_match[] = {
650	{
651		.compatible	= "ti,omap2-mailbox",
652		.data		= (void *)MBOX_INTR_CFG_TYPE1,
653	},
654	{
655		.compatible	= "ti,omap3-mailbox",
656		.data		= (void *)MBOX_INTR_CFG_TYPE1,
657	},
658	{
659		.compatible	= "ti,omap4-mailbox",
660		.data		= (void *)MBOX_INTR_CFG_TYPE2,
 
 
 
 
 
 
 
 
661	},
662	{
663		/* end */
664	},
665};
666MODULE_DEVICE_TABLE(of, omap_mailbox_of_match);
667
668static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
669					    const struct of_phandle_args *sp)
670{
671	phandle phandle = sp->args[0];
672	struct device_node *node;
673	struct omap_mbox_device *mdev;
674	struct omap_mbox *mbox;
 
675
676	mdev = container_of(controller, struct omap_mbox_device, controller);
677	if (WARN_ON(!mdev))
678		return ERR_PTR(-EINVAL);
679
680	node = of_find_node_by_phandle(phandle);
681	if (!node) {
682		pr_err("%s: could not find node phandle 0x%x\n",
683		       __func__, phandle);
684		return ERR_PTR(-ENODEV);
685	}
686
687	mbox = omap_mbox_device_find(mdev, node->name);
 
 
 
 
 
 
 
688	of_node_put(node);
689	return mbox ? mbox->chan : ERR_PTR(-ENOENT);
690}
691
692static int omap_mbox_probe(struct platform_device *pdev)
693{
694	struct resource *mem;
695	int ret;
696	struct mbox_chan *chnls;
697	struct omap_mbox **list, *mbox, *mboxblk;
698	struct omap_mbox_fifo_info *finfo, *finfoblk;
699	struct omap_mbox_device *mdev;
700	struct omap_mbox_fifo *fifo;
701	struct device_node *node = pdev->dev.of_node;
702	struct device_node *child;
703	const struct of_device_id *match;
 
704	u32 intr_type, info_count;
705	u32 num_users, num_fifos;
706	u32 tmp[3];
707	u32 l;
708	int i;
709
710	if (!node) {
711		pr_err("%s: only DT-based devices are supported\n", __func__);
712		return -ENODEV;
713	}
714
715	match = of_match_device(omap_mailbox_of_match, &pdev->dev);
716	if (!match)
717		return -ENODEV;
718	intr_type = (u32)match->data;
719
720	if (of_property_read_u32(node, "ti,mbox-num-users", &num_users))
721		return -ENODEV;
722
723	if (of_property_read_u32(node, "ti,mbox-num-fifos", &num_fifos))
724		return -ENODEV;
725
726	info_count = of_get_available_child_count(node);
727	if (!info_count) {
728		dev_err(&pdev->dev, "no available mbox devices found\n");
729		return -ENODEV;
730	}
731
732	finfoblk = devm_kzalloc(&pdev->dev, info_count * sizeof(*finfoblk),
733				GFP_KERNEL);
734	if (!finfoblk)
 
 
 
 
 
 
 
 
 
 
 
 
 
735		return -ENOMEM;
736
737	finfo = finfoblk;
738	child = NULL;
739	for (i = 0; i < info_count; i++, finfo++) {
 
 
 
 
 
 
 
740		child = of_get_next_available_child(node, child);
741		ret = of_property_read_u32_array(child, "ti,mbox-tx", tmp,
742						 ARRAY_SIZE(tmp));
743		if (ret)
744			return ret;
745		finfo->tx_id = tmp[0];
746		finfo->tx_irq = tmp[1];
747		finfo->tx_usr = tmp[2];
748
749		ret = of_property_read_u32_array(child, "ti,mbox-rx", tmp,
750						 ARRAY_SIZE(tmp));
751		if (ret)
752			return ret;
753		finfo->rx_id = tmp[0];
754		finfo->rx_irq = tmp[1];
755		finfo->rx_usr = tmp[2];
756
757		finfo->name = child->name;
758
759		if (of_find_property(child, "ti,mbox-send-noirq", NULL))
760			finfo->send_no_irq = true;
761
762		if (finfo->tx_id >= num_fifos || finfo->rx_id >= num_fifos ||
763		    finfo->tx_usr >= num_users || finfo->rx_usr >= num_users)
764			return -EINVAL;
765	}
766
767	mdev = devm_kzalloc(&pdev->dev, sizeof(*mdev), GFP_KERNEL);
768	if (!mdev)
769		return -ENOMEM;
770
771	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
772	mdev->mbox_base = devm_ioremap_resource(&pdev->dev, mem);
773	if (IS_ERR(mdev->mbox_base))
774		return PTR_ERR(mdev->mbox_base);
775
776	mdev->irq_ctx = devm_kzalloc(&pdev->dev, num_users * sizeof(u32),
777				     GFP_KERNEL);
778	if (!mdev->irq_ctx)
779		return -ENOMEM;
780
781	/* allocate one extra for marking end of list */
782	list = devm_kzalloc(&pdev->dev, (info_count + 1) * sizeof(*list),
783			    GFP_KERNEL);
784	if (!list)
785		return -ENOMEM;
786
787	chnls = devm_kzalloc(&pdev->dev, (info_count + 1) * sizeof(*chnls),
788			     GFP_KERNEL);
789	if (!chnls)
790		return -ENOMEM;
791
792	mboxblk = devm_kzalloc(&pdev->dev, info_count * sizeof(*mbox),
793			       GFP_KERNEL);
794	if (!mboxblk)
795		return -ENOMEM;
796
797	mbox = mboxblk;
798	finfo = finfoblk;
799	for (i = 0; i < info_count; i++, finfo++) {
800		fifo = &mbox->tx_fifo;
801		fifo->msg = MAILBOX_MESSAGE(finfo->tx_id);
802		fifo->fifo_stat = MAILBOX_FIFOSTATUS(finfo->tx_id);
803		fifo->intr_bit = MAILBOX_IRQ_NOTFULL(finfo->tx_id);
804		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, finfo->tx_usr);
805		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, finfo->tx_usr);
806		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, finfo->tx_usr);
807
808		fifo = &mbox->rx_fifo;
809		fifo->msg = MAILBOX_MESSAGE(finfo->rx_id);
810		fifo->msg_stat =  MAILBOX_MSGSTATUS(finfo->rx_id);
811		fifo->intr_bit = MAILBOX_IRQ_NEWMSG(finfo->rx_id);
812		fifo->irqenable = MAILBOX_IRQENABLE(intr_type, finfo->rx_usr);
813		fifo->irqstatus = MAILBOX_IRQSTATUS(intr_type, finfo->rx_usr);
814		fifo->irqdisable = MAILBOX_IRQDISABLE(intr_type, finfo->rx_usr);
815
816		mbox->send_no_irq = finfo->send_no_irq;
817		mbox->intr_type = intr_type;
818
819		mbox->parent = mdev;
820		mbox->name = finfo->name;
821		mbox->irq = platform_get_irq(pdev, finfo->tx_irq);
822		if (mbox->irq < 0)
823			return mbox->irq;
824		mbox->chan = &chnls[i];
825		chnls[i].con_priv = mbox;
826		list[i] = mbox++;
827	}
828
829	mutex_init(&mdev->cfg_lock);
830	mdev->dev = &pdev->dev;
831	mdev->num_users = num_users;
832	mdev->num_fifos = num_fifos;
833	mdev->intr_type = intr_type;
834	mdev->mboxes = list;
835
836	/* OMAP does not have a Tx-Done IRQ, but rather a Tx-Ready IRQ */
837	mdev->controller.txdone_irq = true;
838	mdev->controller.dev = mdev->dev;
839	mdev->controller.ops = &omap_mbox_chan_ops;
840	mdev->controller.chans = chnls;
841	mdev->controller.num_chans = info_count;
842	mdev->controller.of_xlate = omap_mbox_of_xlate;
843	ret = omap_mbox_register(mdev);
 
 
 
 
 
 
844	if (ret)
845		return ret;
846
847	platform_set_drvdata(pdev, mdev);
848	pm_runtime_enable(mdev->dev);
849
850	ret = pm_runtime_get_sync(mdev->dev);
851	if (ret < 0) {
852		pm_runtime_put_noidle(mdev->dev);
853		goto unregister;
854	}
855
856	/*
857	 * just print the raw revision register, the format is not
858	 * uniform across all SoCs
859	 */
860	l = mbox_read_reg(mdev, MAILBOX_REVISION);
861	dev_info(mdev->dev, "omap mailbox rev 0x%x\n", l);
862
863	ret = pm_runtime_put_sync(mdev->dev);
864	if (ret < 0)
865		goto unregister;
866
867	devm_kfree(&pdev->dev, finfoblk);
868	return 0;
869
870unregister:
871	pm_runtime_disable(mdev->dev);
872	omap_mbox_unregister(mdev);
873	return ret;
874}
875
876static int omap_mbox_remove(struct platform_device *pdev)
877{
878	struct omap_mbox_device *mdev = platform_get_drvdata(pdev);
879
880	pm_runtime_disable(mdev->dev);
881	omap_mbox_unregister(mdev);
882
883	return 0;
884}
885
886static struct platform_driver omap_mbox_driver = {
887	.probe	= omap_mbox_probe,
888	.remove	= omap_mbox_remove,
889	.driver	= {
890		.name = "omap-mailbox",
891		.pm = &omap_mbox_pm_ops,
892		.of_match_table = of_match_ptr(omap_mailbox_of_match),
893	},
894};
895
896static int __init omap_mbox_init(void)
897{
898	int err;
899
900	err = class_register(&omap_mbox_class);
901	if (err)
902		return err;
903
904	/* kfifo size sanity check: alignment and minimal size */
905	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
906	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
907							sizeof(mbox_msg_t));
908
909	return platform_driver_register(&omap_mbox_driver);
910}
911subsys_initcall(omap_mbox_init);
912
913static void __exit omap_mbox_exit(void)
914{
915	platform_driver_unregister(&omap_mbox_driver);
916	class_unregister(&omap_mbox_class);
917}
918module_exit(omap_mbox_exit);
919
920MODULE_LICENSE("GPL v2");
921MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
922MODULE_AUTHOR("Toshihiro Kobayashi");
923MODULE_AUTHOR("Hiroshi DOYU");