1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2020 Linaro Limited.
4  */
5 
6 #define LOG_CATEGORY UCLASS_SCMI_AGENT
7 
8 #include <common.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <scmi_agent-uclass.h>
12 #include <scmi_protocols.h>
13 #include <dm/device_compat.h>
14 #include <dm/device-internal.h>
15 #include <linux/compat.h>
16 
17 /**
18  * struct error_code - Helper structure for SCMI error code conversion
19  * @scmi:	SCMI error code
20  * @errno:	Related standard error number
21  */
22 struct error_code {
23 	int scmi;
24 	int errno;
25 };
26 
27 static const struct error_code scmi_linux_errmap[] = {
28 	{ .scmi = SCMI_NOT_SUPPORTED, .errno = -EOPNOTSUPP, },
29 	{ .scmi = SCMI_INVALID_PARAMETERS, .errno = -EINVAL, },
30 	{ .scmi = SCMI_DENIED, .errno = -EACCES, },
31 	{ .scmi = SCMI_NOT_FOUND, .errno = -ENOENT, },
32 	{ .scmi = SCMI_OUT_OF_RANGE, .errno = -ERANGE, },
33 	{ .scmi = SCMI_BUSY, .errno = -EBUSY, },
34 	{ .scmi = SCMI_COMMS_ERROR, .errno = -ECOMM, },
35 	{ .scmi = SCMI_GENERIC_ERROR, .errno = -EIO, },
36 	{ .scmi = SCMI_HARDWARE_ERROR, .errno = -EREMOTEIO, },
37 	{ .scmi = SCMI_PROTOCOL_ERROR, .errno = -EPROTO, },
38 };
39 
scmi_to_linux_errno(s32 scmi_code)40 int scmi_to_linux_errno(s32 scmi_code)
41 {
42 	int n;
43 
44 	if (!scmi_code)
45 		return 0;
46 
47 	for (n = 0; n < ARRAY_SIZE(scmi_linux_errmap); n++)
48 		if (scmi_code == scmi_linux_errmap[n].scmi)
49 			return scmi_linux_errmap[1].errno;
50 
51 	return -EPROTO;
52 }
53 
54 /*
55  * SCMI agent devices binds devices of various uclasses depeding on
56  * the FDT description. scmi_bind_protocol() is a generic bind sequence
57  * called by the uclass at bind stage, that is uclass post_bind.
58  */
scmi_bind_protocols(struct udevice * dev)59 static int scmi_bind_protocols(struct udevice *dev)
60 {
61 	int ret = 0;
62 	ofnode node;
63 
64 	dev_for_each_subnode(node, dev) {
65 		struct driver *drv = NULL;
66 		u32 protocol_id;
67 
68 		if (!ofnode_is_available(node))
69 			continue;
70 
71 		if (ofnode_read_u32(node, "reg", &protocol_id))
72 			continue;
73 
74 		switch (protocol_id) {
75 		case SCMI_PROTOCOL_ID_CLOCK:
76 			if (IS_ENABLED(CONFIG_CLK_SCMI))
77 				drv = DM_DRIVER_GET(scmi_clock);
78 			break;
79 		case SCMI_PROTOCOL_ID_RESET_DOMAIN:
80 			if (IS_ENABLED(CONFIG_RESET_SCMI))
81 				drv = DM_DRIVER_GET(scmi_reset_domain);
82 			break;
83 		default:
84 			break;
85 		}
86 
87 		if (!drv) {
88 			dev_dbg(dev, "Ignore unsupported SCMI protocol %#x\n",
89 				protocol_id);
90 			continue;
91 		}
92 
93 		ret = device_bind(dev, drv, ofnode_get_name(node), NULL, node,
94 				  NULL);
95 		if (ret)
96 			break;
97 	}
98 
99 	return ret;
100 }
101 
transport_dev_ops(struct udevice * dev)102 static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
103 {
104 	return (const struct scmi_agent_ops *)dev->driver->ops;
105 }
106 
devm_scmi_process_msg(struct udevice * dev,struct scmi_msg * msg)107 int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg)
108 {
109 	const struct scmi_agent_ops *ops = transport_dev_ops(dev);
110 
111 	if (ops->process_msg)
112 		return ops->process_msg(dev, msg);
113 
114 	return -EPROTONOSUPPORT;
115 }
116 
117 UCLASS_DRIVER(scmi_agent) = {
118 	.id		= UCLASS_SCMI_AGENT,
119 	.name		= "scmi_agent",
120 	.post_bind	= scmi_bind_protocols,
121 };
122