blob: 67d2f45002490ab64a6bc997eda93a8f4681d99b [file] [log] [blame]
Etienne Carriere2b412082020-09-09 18:44:01 +02001// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2015-2019, Arm Limited and Contributors. All rights reserved.
Etienne Carrierec624c972022-05-31 18:09:16 +02004 * Copyright (C) 2019-2022 Linaro Limited.
Etienne Carriere2b412082020-09-09 18:44:01 +02005 */
6
Patrick Delaunay5dd84d42021-02-24 11:19:44 +01007#define LOG_CATEGORY UCLASS_SCMI_AGENT
8
Etienne Carriere2b412082020-09-09 18:44:01 +02009#include <cpu_func.h>
10#include <dm.h>
Sean Anderson31786fe2020-10-04 21:39:44 -040011#include <dm/device_compat.h>
Etienne Carriere2b412082020-09-09 18:44:01 +020012#include <errno.h>
13#include <scmi_agent.h>
14#include <asm/cache.h>
15#include <asm/system.h>
16#include <dm/ofnode.h>
17#include <linux/compat.h>
18#include <linux/io.h>
19#include <linux/ioport.h>
20
21#include "smt.h"
22
23/**
24 * Get shared memory configuration defined by the referred DT phandle
25 * Return with a errno compliant value.
26 */
27int scmi_dt_get_smt_buffer(struct udevice *dev, struct scmi_smt *smt)
28{
29 int ret;
30 struct ofnode_phandle_args args;
31 struct resource resource;
Etienne Carriere2b412082020-09-09 18:44:01 +020032
33 ret = dev_read_phandle_with_args(dev, "shmem", NULL, 0, 0, &args);
34 if (ret)
35 return ret;
36
37 ret = ofnode_read_resource(args.node, 0, &resource);
38 if (ret)
39 return ret;
40
Etienne Carriere2b412082020-09-09 18:44:01 +020041 smt->size = resource_size(&resource);
42 if (smt->size < sizeof(struct scmi_smt_header)) {
43 dev_err(dev, "Shared memory buffer too small\n");
44 return -EINVAL;
45 }
46
Patrick Delaunay2a28c6e2021-04-06 09:38:06 +020047 smt->buf = devm_ioremap(dev, resource.start, smt->size);
Etienne Carriere2b412082020-09-09 18:44:01 +020048 if (!smt->buf)
49 return -ENOMEM;
50
51#ifdef CONFIG_ARM
52 if (dcache_status())
Patrick Delaunayab5154f2021-03-16 09:29:40 +010053 mmu_set_region_dcache_behaviour(ALIGN_DOWN((uintptr_t)smt->buf, MMU_SECTION_SIZE),
54 ALIGN(smt->size, MMU_SECTION_SIZE),
55 DCACHE_OFF);
56
Etienne Carriere2b412082020-09-09 18:44:01 +020057#endif
58
59 return 0;
60}
61
62/**
63 * Write SCMI message @msg into a SMT shared buffer @smt.
64 * Return 0 on success and with a negative errno in case of error.
65 */
66int scmi_write_msg_to_smt(struct udevice *dev, struct scmi_smt *smt,
67 struct scmi_msg *msg)
68{
69 struct scmi_smt_header *hdr = (void *)smt->buf;
70
71 if ((!msg->in_msg && msg->in_msg_sz) ||
72 (!msg->out_msg && msg->out_msg_sz))
73 return -EINVAL;
74
75 if (!(hdr->channel_status & SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE)) {
76 dev_dbg(dev, "Channel busy\n");
77 return -EBUSY;
78 }
79
80 if (smt->size < (sizeof(*hdr) + msg->in_msg_sz) ||
81 smt->size < (sizeof(*hdr) + msg->out_msg_sz)) {
82 dev_dbg(dev, "Buffer too small\n");
83 return -ETOOSMALL;
84 }
85
86 /* Load message in shared memory */
87 hdr->channel_status &= ~SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE;
88 hdr->length = msg->in_msg_sz + sizeof(hdr->msg_header);
89 hdr->msg_header = SMT_HEADER_TOKEN(0) |
90 SMT_HEADER_MESSAGE_TYPE(0) |
91 SMT_HEADER_PROTOCOL_ID(msg->protocol_id) |
92 SMT_HEADER_MESSAGE_ID(msg->message_id);
93
94 memcpy_toio(hdr->msg_payload, msg->in_msg, msg->in_msg_sz);
95
96 return 0;
97}
98
99/**
100 * Read SCMI message from a SMT shared buffer @smt and copy it into @msg.
101 * Return 0 on success and with a negative errno in case of error.
102 */
103int scmi_read_resp_from_smt(struct udevice *dev, struct scmi_smt *smt,
104 struct scmi_msg *msg)
105{
106 struct scmi_smt_header *hdr = (void *)smt->buf;
107
108 if (!(hdr->channel_status & SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE)) {
109 dev_err(dev, "Channel unexpectedly busy\n");
110 return -EBUSY;
111 }
112
113 if (hdr->channel_status & SCMI_SHMEM_CHAN_STAT_CHANNEL_ERROR) {
114 dev_err(dev, "Channel error reported, reset channel\n");
115 return -ECOMM;
116 }
117
118 if (hdr->length > msg->out_msg_sz + sizeof(hdr->msg_header)) {
119 dev_err(dev, "Buffer to small\n");
120 return -ETOOSMALL;
121 }
122
123 /* Get the data */
124 msg->out_msg_sz = hdr->length - sizeof(hdr->msg_header);
125 memcpy_fromio(msg->out_msg, hdr->msg_payload, msg->out_msg_sz);
126
127 return 0;
128}
129
130/**
131 * Clear SMT flags in shared buffer to allow further message exchange
132 */
133void scmi_clear_smt_channel(struct scmi_smt *smt)
134{
135 struct scmi_smt_header *hdr = (void *)smt->buf;
136
137 hdr->channel_status &= ~SCMI_SHMEM_CHAN_STAT_CHANNEL_ERROR;
138}
Etienne Carrierec624c972022-05-31 18:09:16 +0200139
140/**
141 * Write SCMI message @msg into a SMT_MSG shared buffer @smt.
142 * Return 0 on success and with a negative errno in case of error.
143 */
144int scmi_msg_to_smt_msg(struct udevice *dev, struct scmi_smt *smt,
145 struct scmi_msg *msg, size_t *buf_size)
146{
147 struct scmi_smt_msg_header *hdr = (void *)smt->buf;
148
149 if ((!msg->in_msg && msg->in_msg_sz) ||
150 (!msg->out_msg && msg->out_msg_sz))
151 return -EINVAL;
152
153 if (smt->size < (sizeof(*hdr) + msg->in_msg_sz) ||
154 smt->size < (sizeof(*hdr) + msg->out_msg_sz)) {
155 dev_dbg(dev, "Buffer too small\n");
156 return -ETOOSMALL;
157 }
158
159 *buf_size = msg->in_msg_sz + sizeof(hdr->msg_header);
160
161 hdr->msg_header = SMT_HEADER_TOKEN(0) |
162 SMT_HEADER_MESSAGE_TYPE(0) |
163 SMT_HEADER_PROTOCOL_ID(msg->protocol_id) |
164 SMT_HEADER_MESSAGE_ID(msg->message_id);
165
166 memcpy(hdr->msg_payload, msg->in_msg, msg->in_msg_sz);
167
168 return 0;
169}
170
171/**
172 * Read SCMI message from a SMT shared buffer @smt and copy it into @msg.
173 * Return 0 on success and with a negative errno in case of error.
174 */
175int scmi_msg_from_smt_msg(struct udevice *dev, struct scmi_smt *smt,
176 struct scmi_msg *msg, size_t buf_size)
177{
178 struct scmi_smt_msg_header *hdr = (void *)smt->buf;
179
180 if (buf_size > msg->out_msg_sz + sizeof(hdr->msg_header)) {
181 dev_err(dev, "Buffer to small\n");
182 return -ETOOSMALL;
183 }
184
185 msg->out_msg_sz = buf_size - sizeof(hdr->msg_header);
186 memcpy(msg->out_msg, hdr->msg_payload, msg->out_msg_sz);
187
188 return 0;
189}