xref: /openbmc/linux/drivers/remoteproc/omap_remoteproc.c (revision ce932d0c5589e9766e089c22c66890dfc48fbd94)
1 /*
2  * OMAP Remote Processor driver
3  *
4  * Copyright (C) 2011 Texas Instruments, Inc.
5  * Copyright (C) 2011 Google, Inc.
6  *
7  * Ohad Ben-Cohen <ohad@wizery.com>
8  * Brian Swetland <swetland@google.com>
9  * Fernando Guzman Lugo <fernando.lugo@ti.com>
10  * Mark Grosen <mgrosen@ti.com>
11  * Suman Anna <s-anna@ti.com>
12  * Hari Kanigeri <h-kanigeri2@ti.com>
13  *
14  * This program is free software; you can redistribute it and/or
15  * modify it under the terms of the GNU General Public License
16  * version 2 as published by the Free Software Foundation.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  */
23 
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/err.h>
27 #include <linux/platform_device.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/remoteproc.h>
30 
31 #include <plat/mailbox.h>
32 #include <plat/remoteproc.h>
33 
34 #include "omap_remoteproc.h"
35 #include "remoteproc_internal.h"
36 
37 /**
38  * struct omap_rproc - omap remote processor state
39  * @mbox: omap mailbox handle
40  * @nb: notifier block that will be invoked on inbound mailbox messages
41  * @rproc: rproc handle
42  */
43 struct omap_rproc {
44 	struct omap_mbox *mbox;
45 	struct notifier_block nb;
46 	struct rproc *rproc;
47 };
48 
49 /**
50  * omap_rproc_mbox_callback() - inbound mailbox message handler
51  * @this: notifier block
52  * @index: unused
53  * @data: mailbox payload
54  *
55  * This handler is invoked by omap's mailbox driver whenever a mailbox
56  * message is received. Usually, the mailbox payload simply contains
57  * the index of the virtqueue that is kicked by the remote processor,
58  * and we let remoteproc core handle it.
59  *
60  * In addition to virtqueue indices, we also have some out-of-band values
61  * that indicates different events. Those values are deliberately very
62  * big so they don't coincide with virtqueue indices.
63  */
64 static int omap_rproc_mbox_callback(struct notifier_block *this,
65 					unsigned long index, void *data)
66 {
67 	mbox_msg_t msg = (mbox_msg_t) data;
68 	struct omap_rproc *oproc = container_of(this, struct omap_rproc, nb);
69 	struct device *dev = oproc->rproc->dev;
70 	const char *name = oproc->rproc->name;
71 
72 	dev_dbg(dev, "mbox msg: 0x%x\n", msg);
73 
74 	switch (msg) {
75 	case RP_MBOX_CRASH:
76 		/* just log this for now. later, we'll also do recovery */
77 		dev_err(dev, "omap rproc %s crashed\n", name);
78 		break;
79 	case RP_MBOX_ECHO_REPLY:
80 		dev_info(dev, "received echo reply from %s\n", name);
81 		break;
82 	default:
83 		/* msg contains the index of the triggered vring */
84 		if (rproc_vq_interrupt(oproc->rproc, msg) == IRQ_NONE)
85 			dev_dbg(dev, "no message was found in vqid %d\n", msg);
86 	}
87 
88 	return NOTIFY_DONE;
89 }
90 
91 /* kick a virtqueue */
92 static void omap_rproc_kick(struct rproc *rproc, int vqid)
93 {
94 	struct omap_rproc *oproc = rproc->priv;
95 	int ret;
96 
97 	/* send the index of the triggered virtqueue in the mailbox payload */
98 	ret = omap_mbox_msg_send(oproc->mbox, vqid);
99 	if (ret)
100 		dev_err(rproc->dev, "omap_mbox_msg_send failed: %d\n", ret);
101 }
102 
103 /*
104  * Power up the remote processor.
105  *
106  * This function will be invoked only after the firmware for this rproc
107  * was loaded, parsed successfully, and all of its resource requirements
108  * were met.
109  */
110 static int omap_rproc_start(struct rproc *rproc)
111 {
112 	struct omap_rproc *oproc = rproc->priv;
113 	struct platform_device *pdev = to_platform_device(rproc->dev);
114 	struct omap_rproc_pdata *pdata = pdev->dev.platform_data;
115 	int ret;
116 
117 	oproc->nb.notifier_call = omap_rproc_mbox_callback;
118 
119 	/* every omap rproc is assigned a mailbox instance for messaging */
120 	oproc->mbox = omap_mbox_get(pdata->mbox_name, &oproc->nb);
121 	if (IS_ERR(oproc->mbox)) {
122 		ret = PTR_ERR(oproc->mbox);
123 		dev_err(rproc->dev, "omap_mbox_get failed: %d\n", ret);
124 		return ret;
125 	}
126 
127 	/*
128 	 * Ping the remote processor. this is only for sanity-sake;
129 	 * there is no functional effect whatsoever.
130 	 *
131 	 * Note that the reply will _not_ arrive immediately: this message
132 	 * will wait in the mailbox fifo until the remote processor is booted.
133 	 */
134 	ret = omap_mbox_msg_send(oproc->mbox, RP_MBOX_ECHO_REQUEST);
135 	if (ret) {
136 		dev_err(rproc->dev, "omap_mbox_get failed: %d\n", ret);
137 		goto put_mbox;
138 	}
139 
140 	ret = pdata->device_enable(pdev);
141 	if (ret) {
142 		dev_err(rproc->dev, "omap_device_enable failed: %d\n", ret);
143 		goto put_mbox;
144 	}
145 
146 	return 0;
147 
148 put_mbox:
149 	omap_mbox_put(oproc->mbox, &oproc->nb);
150 	return ret;
151 }
152 
153 /* power off the remote processor */
154 static int omap_rproc_stop(struct rproc *rproc)
155 {
156 	struct platform_device *pdev = to_platform_device(rproc->dev);
157 	struct omap_rproc_pdata *pdata = pdev->dev.platform_data;
158 	struct omap_rproc *oproc = rproc->priv;
159 	int ret;
160 
161 	ret = pdata->device_shutdown(pdev);
162 	if (ret)
163 		return ret;
164 
165 	omap_mbox_put(oproc->mbox, &oproc->nb);
166 
167 	return 0;
168 }
169 
170 static struct rproc_ops omap_rproc_ops = {
171 	.start		= omap_rproc_start,
172 	.stop		= omap_rproc_stop,
173 	.kick		= omap_rproc_kick,
174 };
175 
176 static int __devinit omap_rproc_probe(struct platform_device *pdev)
177 {
178 	struct omap_rproc_pdata *pdata = pdev->dev.platform_data;
179 	struct omap_rproc *oproc;
180 	struct rproc *rproc;
181 	int ret;
182 
183 	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
184 	if (ret) {
185 		dev_err(pdev->dev.parent, "dma_set_coherent_mask: %d\n", ret);
186 		return ret;
187 	}
188 
189 	rproc = rproc_alloc(&pdev->dev, pdata->name, &omap_rproc_ops,
190 				pdata->firmware, sizeof(*oproc));
191 	if (!rproc)
192 		return -ENOMEM;
193 
194 	oproc = rproc->priv;
195 	oproc->rproc = rproc;
196 
197 	platform_set_drvdata(pdev, rproc);
198 
199 	ret = rproc_register(rproc);
200 	if (ret)
201 		goto free_rproc;
202 
203 	return 0;
204 
205 free_rproc:
206 	rproc_free(rproc);
207 	return ret;
208 }
209 
210 static int __devexit omap_rproc_remove(struct platform_device *pdev)
211 {
212 	struct rproc *rproc = platform_get_drvdata(pdev);
213 
214 	return rproc_unregister(rproc);
215 }
216 
217 static struct platform_driver omap_rproc_driver = {
218 	.probe = omap_rproc_probe,
219 	.remove = __devexit_p(omap_rproc_remove),
220 	.driver = {
221 		.name = "omap-rproc",
222 		.owner = THIS_MODULE,
223 	},
224 };
225 
226 module_platform_driver(omap_rproc_driver);
227 
228 MODULE_LICENSE("GPL v2");
229 MODULE_DESCRIPTION("OMAP Remote Processor control driver");
230