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 <log.h>
9 #include <mailbox-uclass.h>
10 #include <malloc.h>
11 #include <asm/io.h>
12 #include <asm/mbox.h>
13
14 #define SANDBOX_MBOX_CHANNELS 2
15
16 struct sandbox_mbox_chan {
17 bool rx_msg_valid;
18 uint32_t rx_msg;
19 };
20
21 struct sandbox_mbox {
22 struct sandbox_mbox_chan chans[SANDBOX_MBOX_CHANNELS];
23 };
24
sandbox_mbox_request(struct mbox_chan * chan)25 static int sandbox_mbox_request(struct mbox_chan *chan)
26 {
27 debug("%s(chan=%p)\n", __func__, chan);
28
29 if (chan->id >= SANDBOX_MBOX_CHANNELS)
30 return -EINVAL;
31
32 return 0;
33 }
34
sandbox_mbox_free(struct mbox_chan * chan)35 static int sandbox_mbox_free(struct mbox_chan *chan)
36 {
37 debug("%s(chan=%p)\n", __func__, chan);
38
39 return 0;
40 }
41
sandbox_mbox_send(struct mbox_chan * chan,const void * data)42 static int sandbox_mbox_send(struct mbox_chan *chan, const void *data)
43 {
44 struct sandbox_mbox *sbm = dev_get_priv(chan->dev);
45 const uint32_t *pmsg = data;
46
47 debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
48
49 sbm->chans[chan->id].rx_msg = *pmsg ^ SANDBOX_MBOX_PING_XOR;
50 sbm->chans[chan->id].rx_msg_valid = true;
51
52 return 0;
53 }
54
sandbox_mbox_recv(struct mbox_chan * chan,void * data)55 static int sandbox_mbox_recv(struct mbox_chan *chan, void *data)
56 {
57 struct sandbox_mbox *sbm = dev_get_priv(chan->dev);
58 uint32_t *pmsg = data;
59
60 debug("%s(chan=%p, data=%p)\n", __func__, chan, data);
61
62 if (!sbm->chans[chan->id].rx_msg_valid)
63 return -ENODATA;
64
65 *pmsg = sbm->chans[chan->id].rx_msg;
66 sbm->chans[chan->id].rx_msg_valid = false;
67
68 return 0;
69 }
70
sandbox_mbox_bind(struct udevice * dev)71 static int sandbox_mbox_bind(struct udevice *dev)
72 {
73 debug("%s(dev=%p)\n", __func__, dev);
74
75 return 0;
76 }
77
sandbox_mbox_probe(struct udevice * dev)78 static int sandbox_mbox_probe(struct udevice *dev)
79 {
80 debug("%s(dev=%p)\n", __func__, dev);
81
82 return 0;
83 }
84
85 static const struct udevice_id sandbox_mbox_ids[] = {
86 { .compatible = "sandbox,mbox" },
87 { }
88 };
89
90 struct mbox_ops sandbox_mbox_mbox_ops = {
91 .request = sandbox_mbox_request,
92 .rfree = sandbox_mbox_free,
93 .send = sandbox_mbox_send,
94 .recv = sandbox_mbox_recv,
95 };
96
97 U_BOOT_DRIVER(sandbox_mbox) = {
98 .name = "sandbox_mbox",
99 .id = UCLASS_MAILBOX,
100 .of_match = sandbox_mbox_ids,
101 .bind = sandbox_mbox_bind,
102 .probe = sandbox_mbox_probe,
103 .priv_auto = sizeof(struct sandbox_mbox),
104 .ops = &sandbox_mbox_mbox_ops,
105 };
106