1 /*
2  * Copyright (c) 2016, NVIDIA CORPORATION.
3  *
4  * SPDX-License-Identifier: GPL-2.0
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <mailbox.h>
10 #include <mailbox-uclass.h>
11 
12 static inline struct mbox_ops *mbox_dev_ops(struct udevice *dev)
13 {
14 	return (struct mbox_ops *)dev->driver->ops;
15 }
16 
17 static int mbox_of_xlate_default(struct mbox_chan *chan,
18 				 struct ofnode_phandle_args *args)
19 {
20 	debug("%s(chan=%p)\n", __func__, chan);
21 
22 	if (args->args_count != 1) {
23 		debug("Invaild args_count: %d\n", args->args_count);
24 		return -EINVAL;
25 	}
26 
27 	chan->id = args->args[0];
28 
29 	return 0;
30 }
31 
32 int mbox_get_by_index(struct udevice *dev, int index, struct mbox_chan *chan)
33 {
34 	struct ofnode_phandle_args args;
35 	int ret;
36 	struct udevice *dev_mbox;
37 	struct mbox_ops *ops;
38 
39 	debug("%s(dev=%p, index=%d, chan=%p)\n", __func__, dev, index, chan);
40 
41 	ret = dev_read_phandle_with_args(dev, "mboxes", "#mbox-cells", 0, index,
42 					 &args);
43 	if (ret) {
44 		debug("%s: dev_read_phandle_with_args failed: %d\n", __func__,
45 		      ret);
46 		return ret;
47 	}
48 
49 	ret = uclass_get_device_by_ofnode(UCLASS_MAILBOX, args.node, &dev_mbox);
50 	if (ret) {
51 		debug("%s: uclass_get_device_by_of_offset failed: %d\n",
52 		      __func__, ret);
53 		return ret;
54 	}
55 	ops = mbox_dev_ops(dev_mbox);
56 
57 	chan->dev = dev_mbox;
58 	if (ops->of_xlate)
59 		ret = ops->of_xlate(chan, &args);
60 	else
61 		ret = mbox_of_xlate_default(chan, &args);
62 	if (ret) {
63 		debug("of_xlate() failed: %d\n", ret);
64 		return ret;
65 	}
66 
67 	ret = ops->request(chan);
68 	if (ret) {
69 		debug("ops->request() failed: %d\n", ret);
70 		return ret;
71 	}
72 
73 	return 0;
74 }
75 
76 int mbox_get_by_name(struct udevice *dev, const char *name,
77 		     struct mbox_chan *chan)
78 {
79 	int index;
80 
81 	debug("%s(dev=%p, name=%s, chan=%p)\n", __func__, dev, name, chan);
82 
83 	index = dev_read_stringlist_search(dev, "mbox-names", name);
84 	if (index < 0) {
85 		debug("fdt_stringlist_search() failed: %d\n", index);
86 		return index;
87 	}
88 
89 	return mbox_get_by_index(dev, index, chan);
90 }
91 
92 int mbox_free(struct mbox_chan *chan)
93 {
94 	struct mbox_ops *ops = mbox_dev_ops(chan->dev);
95 
96 	debug("%s(chan=%p)\n", __func__, chan);
97 
98 	return ops->free(chan);
99 }
100 
101 int mbox_send(struct mbox_chan *chan, const void *data)
102 {
103 	struct mbox_ops *ops = mbox_dev_ops(chan->dev);
104 
105 	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
106 
107 	return ops->send(chan, data);
108 }
109 
110 int mbox_recv(struct mbox_chan *chan, void *data, ulong timeout_us)
111 {
112 	struct mbox_ops *ops = mbox_dev_ops(chan->dev);
113 	ulong start_time;
114 	int ret;
115 
116 	debug("%s(chan=%p, data=%p, timeout_us=%ld)\n", __func__, chan, data,
117 	      timeout_us);
118 
119 	start_time = timer_get_us();
120 	/*
121 	 * Account for partial us ticks, but if timeout_us is 0, ensure we
122 	 * still don't wait at all.
123 	 */
124 	if (timeout_us)
125 		timeout_us++;
126 
127 	for (;;) {
128 		ret = ops->recv(chan, data);
129 		if (ret != -ENODATA)
130 			return ret;
131 		if ((timer_get_us() - start_time) >= timeout_us)
132 			return -ETIMEDOUT;
133 	}
134 }
135 
136 UCLASS_DRIVER(mailbox) = {
137 	.id		= UCLASS_MAILBOX,
138 	.name		= "mailbox",
139 };
140