1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2015-2019, Arm Limited and Contributors. All rights reserved.
* Copyright (C) 2019-2020 Linaro Limited.
*/
#define LOG_CATEGORY UCLASS_SCMI_AGENT
#include <common.h>
#include <cpu_func.h>
#include <dm.h>
#include <dm/device_compat.h>
#include <errno.h>
#include <scmi_agent.h>
#include <asm/cache.h>
#include <asm/system.h>
#include <dm/ofnode.h>
#include <linux/compat.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include "smt.h"
/**
* Get shared memory configuration defined by the referred DT phandle
* Return with a errno compliant value.
*/
int scmi_dt_get_smt_buffer(struct udevice *dev, struct scmi_smt *smt)
{
int ret;
struct ofnode_phandle_args args;
struct resource resource;
ret = dev_read_phandle_with_args(dev, "shmem", NULL, 0, 0, &args);
if (ret)
return ret;
ret = ofnode_read_resource(args.node, 0, &resource);
if (ret)
return ret;
smt->size = resource_size(&resource);
if (smt->size < sizeof(struct scmi_smt_header)) {
dev_err(dev, "Shared memory buffer too small\n");
return -EINVAL;
}
smt->buf = devm_ioremap(dev, resource.start, smt->size);
if (!smt->buf)
return -ENOMEM;
#ifdef CONFIG_ARM
if (dcache_status())
mmu_set_region_dcache_behaviour(ALIGN_DOWN((uintptr_t)smt->buf, MMU_SECTION_SIZE),
ALIGN(smt->size, MMU_SECTION_SIZE),
DCACHE_OFF);
#endif
return 0;
}
/**
* Write SCMI message @msg into a SMT shared buffer @smt.
* Return 0 on success and with a negative errno in case of error.
*/
int scmi_write_msg_to_smt(struct udevice *dev, struct scmi_smt *smt,
struct scmi_msg *msg)
{
struct scmi_smt_header *hdr = (void *)smt->buf;
if ((!msg->in_msg && msg->in_msg_sz) ||
(!msg->out_msg && msg->out_msg_sz))
return -EINVAL;
if (!(hdr->channel_status & SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE)) {
dev_dbg(dev, "Channel busy\n");
return -EBUSY;
}
if (smt->size < (sizeof(*hdr) + msg->in_msg_sz) ||
smt->size < (sizeof(*hdr) + msg->out_msg_sz)) {
dev_dbg(dev, "Buffer too small\n");
return -ETOOSMALL;
}
/* Load message in shared memory */
hdr->channel_status &= ~SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE;
hdr->length = msg->in_msg_sz + sizeof(hdr->msg_header);
hdr->msg_header = SMT_HEADER_TOKEN(0) |
SMT_HEADER_MESSAGE_TYPE(0) |
SMT_HEADER_PROTOCOL_ID(msg->protocol_id) |
SMT_HEADER_MESSAGE_ID(msg->message_id);
memcpy_toio(hdr->msg_payload, msg->in_msg, msg->in_msg_sz);
return 0;
}
/**
* Read SCMI message from a SMT shared buffer @smt and copy it into @msg.
* Return 0 on success and with a negative errno in case of error.
*/
int scmi_read_resp_from_smt(struct udevice *dev, struct scmi_smt *smt,
struct scmi_msg *msg)
{
struct scmi_smt_header *hdr = (void *)smt->buf;
if (!(hdr->channel_status & SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE)) {
dev_err(dev, "Channel unexpectedly busy\n");
return -EBUSY;
}
if (hdr->channel_status & SCMI_SHMEM_CHAN_STAT_CHANNEL_ERROR) {
dev_err(dev, "Channel error reported, reset channel\n");
return -ECOMM;
}
if (hdr->length > msg->out_msg_sz + sizeof(hdr->msg_header)) {
dev_err(dev, "Buffer to small\n");
return -ETOOSMALL;
}
/* Get the data */
msg->out_msg_sz = hdr->length - sizeof(hdr->msg_header);
memcpy_fromio(msg->out_msg, hdr->msg_payload, msg->out_msg_sz);
return 0;
}
/**
* Clear SMT flags in shared buffer to allow further message exchange
*/
void scmi_clear_smt_channel(struct scmi_smt *smt)
{
struct scmi_smt_header *hdr = (void *)smt->buf;
hdr->channel_status &= ~SCMI_SHMEM_CHAN_STAT_CHANNEL_ERROR;
}
|
