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 		case SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN:
84 			if (IS_ENABLED(CONFIG_DM_REGULATOR_SCMI)) {
85 				node = ofnode_find_subnode(node, "regulators");
86 				if (!ofnode_valid(node)) {
87 					dev_err(dev, "no regulators node\n");
88 					return -ENXIO;
89 				}
90 				drv = DM_DRIVER_GET(scmi_voltage_domain);
91 			}
92 			break;
93 		default:
94 			break;
95 		}
96 
97 		if (!drv) {
98 			dev_dbg(dev, "Ignore unsupported SCMI protocol %#x\n",
99 				protocol_id);
100 			continue;
101 		}
102 
103 		ret = device_bind(dev, drv, ofnode_get_name(node), NULL, node,
104 				  NULL);
105 		if (ret)
106 			break;
107 	}
108 
109 	return ret;
110 }
111 
transport_dev_ops(struct udevice * dev)112 static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
113 {
114 	return (const struct scmi_agent_ops *)dev->driver->ops;
115 }
116 
devm_scmi_process_msg(struct udevice * dev,struct scmi_msg * msg)117 int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg)
118 {
119 	const struct scmi_agent_ops *ops = transport_dev_ops(dev);
120 
121 	if (ops->process_msg)
122 		return ops->process_msg(dev, msg);
123 
124 	return -EPROTONOSUPPORT;
125 }
126 
127 UCLASS_DRIVER(scmi_agent) = {
128 	.id		= UCLASS_SCMI_AGENT,
129 	.name		= "scmi_agent",
130 	.post_bind	= scmi_bind_protocols,
131 };
132