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