1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0+
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (C) 2020 Linaro Limited.
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #include <common.h>
7*4882a593Smuzhiyun #include <dm.h>
8*4882a593Smuzhiyun #include <errno.h>
9*4882a593Smuzhiyun #include <scmi_agent.h>
10*4882a593Smuzhiyun #include <scmi_agent-uclass.h>
11*4882a593Smuzhiyun #include <dm/device-internal.h>
12*4882a593Smuzhiyun #include <dm/read.h>
13*4882a593Smuzhiyun #include <linux/arm-smccc.h>
14*4882a593Smuzhiyun #include <linux/compat.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun #include "smt.h"
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun #define SMCCC_RET_NOT_SUPPORTED ((unsigned long)-1)
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun /**
21*4882a593Smuzhiyun * struct scmi_smccc_channel - Description of an SCMI SMCCC transport
22*4882a593Smuzhiyun * @func_id: SMCCC function ID used by the SCMI transport
23*4882a593Smuzhiyun * @smt: Shared memory buffer
24*4882a593Smuzhiyun */
25*4882a593Smuzhiyun struct scmi_smccc_channel {
26*4882a593Smuzhiyun ulong func_id;
27*4882a593Smuzhiyun struct scmi_smt smt;
28*4882a593Smuzhiyun };
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun #ifndef CONFIG_SPL_BUILD
scmi_smccc_process_msg(struct udevice * dev,struct scmi_msg * msg)31*4882a593Smuzhiyun static int scmi_smccc_process_msg(struct udevice *dev, struct scmi_msg *msg)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun struct scmi_smccc_channel *chan = dev_get_priv(dev);
34*4882a593Smuzhiyun struct arm_smccc_res res;
35*4882a593Smuzhiyun int ret;
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun ret = scmi_write_msg_to_smt(dev, &chan->smt, msg);
38*4882a593Smuzhiyun if (ret)
39*4882a593Smuzhiyun return ret;
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun arm_smccc_smc(chan->func_id, 0, 0, 0, 0, 0, 0, 0, &res);
42*4882a593Smuzhiyun if (res.a0 == SMCCC_RET_NOT_SUPPORTED)
43*4882a593Smuzhiyun ret = -ENXIO;
44*4882a593Smuzhiyun else
45*4882a593Smuzhiyun ret = scmi_read_resp_from_smt(dev, &chan->smt, msg);
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun scmi_clear_smt_channel(&chan->smt);
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun return ret;
50*4882a593Smuzhiyun }
51*4882a593Smuzhiyun
scmi_smccc_probe(struct udevice * dev)52*4882a593Smuzhiyun static int scmi_smccc_probe(struct udevice *dev)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun struct scmi_smccc_channel *chan = dev_get_priv(dev);
55*4882a593Smuzhiyun u32 func_id;
56*4882a593Smuzhiyun int ret;
57*4882a593Smuzhiyun
58*4882a593Smuzhiyun func_id = dev_read_u32_default(dev, "arm,smc-id", -ENODATA);
59*4882a593Smuzhiyun if (func_id == -ENODATA) {
60*4882a593Smuzhiyun dev_err(dev, "Missing property func-id\n");
61*4882a593Smuzhiyun return -EINVAL;
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun chan->func_id = func_id;
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun ret = scmi_dt_get_smt_buffer(dev, &chan->smt);
67*4882a593Smuzhiyun if (ret) {
68*4882a593Smuzhiyun dev_err(dev, "Failed to get smt resources: %d\n", ret);
69*4882a593Smuzhiyun return ret;
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun return 0;
73*4882a593Smuzhiyun }
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun static const struct scmi_agent_ops scmi_smccc_ops = {
76*4882a593Smuzhiyun .process_msg = scmi_smccc_process_msg,
77*4882a593Smuzhiyun };
78*4882a593Smuzhiyun #endif
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun static const struct udevice_id scmi_smccc_ids[] = {
81*4882a593Smuzhiyun { .compatible = "arm,scmi-smc" },
82*4882a593Smuzhiyun { }
83*4882a593Smuzhiyun };
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun U_BOOT_DRIVER(scmi_smccc) = {
86*4882a593Smuzhiyun .name = "scmi-over-smccc",
87*4882a593Smuzhiyun .id = UCLASS_SCMI_AGENT,
88*4882a593Smuzhiyun .of_match = scmi_smccc_ids,
89*4882a593Smuzhiyun .priv_auto_alloc_size = sizeof(struct scmi_smccc_channel),
90*4882a593Smuzhiyun #ifndef CONFIG_SPL_BUILD
91*4882a593Smuzhiyun .probe = scmi_smccc_probe,
92*4882a593Smuzhiyun .ops = &scmi_smccc_ops,
93*4882a593Smuzhiyun #endif
94*4882a593Smuzhiyun };
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