1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2019-2022 Linaro Limited
4  */
5 
6 #define LOG_CATEGORY UCLASS_RESET
7 
8 #include <dm.h>
9 #include <errno.h>
10 #include <reset-uclass.h>
11 #include <scmi_agent.h>
12 #include <scmi_agent-uclass.h>
13 #include <scmi_protocols.h>
14 #include <asm/types.h>
15 
scmi_reset_set_level(struct reset_ctl * rst,bool assert_not_deassert)16 static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
17 {
18 	struct scmi_rd_reset_in in = {
19 		.domain_id = rst->id,
20 		.flags = assert_not_deassert ? SCMI_RD_RESET_FLAG_ASSERT : 0,
21 		.reset_state = 0,
22 	};
23 	struct scmi_rd_reset_out out;
24 	struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_RESET_DOMAIN,
25 					  SCMI_RESET_DOMAIN_RESET,
26 					  in, out);
27 	int ret;
28 
29 	ret = devm_scmi_process_msg(rst->dev, &msg);
30 	if (ret)
31 		return ret;
32 
33 	return scmi_to_linux_errno(out.status);
34 }
35 
scmi_reset_assert(struct reset_ctl * rst)36 static int scmi_reset_assert(struct reset_ctl *rst)
37 {
38 	return scmi_reset_set_level(rst, true);
39 }
40 
scmi_reset_deassert(struct reset_ctl * rst)41 static int scmi_reset_deassert(struct reset_ctl *rst)
42 {
43 	return scmi_reset_set_level(rst, false);
44 }
45 
scmi_reset_request(struct reset_ctl * rst)46 static int scmi_reset_request(struct reset_ctl *rst)
47 {
48 	struct scmi_rd_attr_in in = {
49 		.domain_id = rst->id,
50 	};
51 	struct scmi_rd_attr_out out;
52 	struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_RESET_DOMAIN,
53 					  SCMI_RESET_DOMAIN_ATTRIBUTES,
54 					  in, out);
55 	int ret;
56 
57 	/*
58 	 * We don't really care about the attribute, just check
59 	 * the reset domain exists.
60 	 */
61 	ret = devm_scmi_process_msg(rst->dev, &msg);
62 	if (ret)
63 		return ret;
64 
65 	return scmi_to_linux_errno(out.status);
66 }
67 
68 static const struct reset_ops scmi_reset_domain_ops = {
69 	.request	= scmi_reset_request,
70 	.rst_assert	= scmi_reset_assert,
71 	.rst_deassert	= scmi_reset_deassert,
72 };
73 
scmi_reset_probe(struct udevice * dev)74 static int scmi_reset_probe(struct udevice *dev)
75 {
76 	return devm_scmi_of_get_channel(dev);
77 }
78 
79 U_BOOT_DRIVER(scmi_reset_domain) = {
80 	.name = "scmi_reset_domain",
81 	.id = UCLASS_RESET,
82 	.ops = &scmi_reset_domain_ops,
83 	.probe = scmi_reset_probe,
84 };
85 
86 static struct scmi_proto_match match[] = {
87 	{ .proto_id = SCMI_PROTOCOL_ID_RESET_DOMAIN },
88 	{ /* Sentinel */ }
89 };
90 
91 U_BOOT_SCMI_PROTO_DRIVER(scmi_reset_domain, match);
92