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
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2021 ARM Ltd.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/arm_ffa.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include "common.h"
static DEFINE_IDA(ffa_bus_id);
static int ffa_device_match(struct device *dev, struct device_driver *drv)
{
const struct ffa_device_id *id_table;
struct ffa_device *ffa_dev;
id_table = to_ffa_driver(drv)->id_table;
ffa_dev = to_ffa_dev(dev);
while (!uuid_is_null(&id_table->uuid)) {
/*
* FF-A v1.0 doesn't provide discovery of UUIDs, just the
* partition IDs, so fetch the partitions IDs for this
* id_table UUID and assign the UUID to the device if the
* partition ID matches
*/
if (uuid_is_null(&ffa_dev->uuid))
ffa_device_match_uuid(ffa_dev, &id_table->uuid);
if (uuid_equal(&ffa_dev->uuid, &id_table->uuid))
return 1;
id_table++;
}
return 0;
}
static int ffa_device_probe(struct device *dev)
{
struct ffa_driver *ffa_drv = to_ffa_driver(dev->driver);
struct ffa_device *ffa_dev = to_ffa_dev(dev);
return ffa_drv->probe(ffa_dev);
}
static void ffa_device_remove(struct device *dev)
{
struct ffa_driver *ffa_drv = to_ffa_driver(dev->driver);
if (ffa_drv->remove)
ffa_drv->remove(to_ffa_dev(dev));
}
static int ffa_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct ffa_device *ffa_dev = to_ffa_dev(dev);
return add_uevent_var(env, "MODALIAS=arm_ffa:%04x:%pUb",
ffa_dev->vm_id, &ffa_dev->uuid);
}
static ssize_t partition_id_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ffa_device *ffa_dev = to_ffa_dev(dev);
return sprintf(buf, "0x%04x\n", ffa_dev->vm_id);
}
static DEVICE_ATTR_RO(partition_id);
static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct ffa_device *ffa_dev = to_ffa_dev(dev);
return sprintf(buf, "%pUb\n", &ffa_dev->uuid);
}
static DEVICE_ATTR_RO(uuid);
static struct attribute *ffa_device_attributes_attrs[] = {
&dev_attr_partition_id.attr,
&dev_attr_uuid.attr,
NULL,
};
ATTRIBUTE_GROUPS(ffa_device_attributes);
struct bus_type ffa_bus_type = {
.name = "arm_ffa",
.match = ffa_device_match,
.probe = ffa_device_probe,
.remove = ffa_device_remove,
.uevent = ffa_device_uevent,
.dev_groups = ffa_device_attributes_groups,
};
EXPORT_SYMBOL_GPL(ffa_bus_type);
int ffa_driver_register(struct ffa_driver *driver, struct module *owner,
const char *mod_name)
{
int ret;
if (!driver->probe)
return -EINVAL;
driver->driver.bus = &ffa_bus_type;
driver->driver.name = driver->name;
driver->driver.owner = owner;
driver->driver.mod_name = mod_name;
ret = driver_register(&driver->driver);
if (!ret)
pr_debug("registered new ffa driver %s\n", driver->name);
return ret;
}
EXPORT_SYMBOL_GPL(ffa_driver_register);
void ffa_driver_unregister(struct ffa_driver *driver)
{
driver_unregister(&driver->driver);
}
EXPORT_SYMBOL_GPL(ffa_driver_unregister);
static void ffa_release_device(struct device *dev)
{
struct ffa_device *ffa_dev = to_ffa_dev(dev);
ida_free(&ffa_bus_id, ffa_dev->id);
kfree(ffa_dev);
}
static int __ffa_devices_unregister(struct device *dev, void *data)
{
device_unregister(dev);
return 0;
}
static void ffa_devices_unregister(void)
{
bus_for_each_dev(&ffa_bus_type, NULL, NULL,
__ffa_devices_unregister);
}
bool ffa_device_is_valid(struct ffa_device *ffa_dev)
{
bool valid = false;
struct device *dev = NULL;
struct ffa_device *tmp_dev;
do {
dev = bus_find_next_device(&ffa_bus_type, dev);
tmp_dev = to_ffa_dev(dev);
if (tmp_dev == ffa_dev) {
valid = true;
break;
}
put_device(dev);
} while (dev);
put_device(dev);
return valid;
}
struct ffa_device *ffa_device_register(const uuid_t *uuid, int vm_id,
const struct ffa_ops *ops)
{
int id, ret;
struct device *dev;
struct ffa_device *ffa_dev;
id = ida_alloc_min(&ffa_bus_id, 1, GFP_KERNEL);
if (id < 0)
return NULL;
ffa_dev = kzalloc(sizeof(*ffa_dev), GFP_KERNEL);
if (!ffa_dev) {
ida_free(&ffa_bus_id, id);
return NULL;
}
dev = &ffa_dev->dev;
dev->bus = &ffa_bus_type;
dev->release = ffa_release_device;
dev_set_name(&ffa_dev->dev, "arm-ffa-%d", id);
ffa_dev->id = id;
ffa_dev->vm_id = vm_id;
ffa_dev->ops = ops;
uuid_copy(&ffa_dev->uuid, uuid);
ret = device_register(&ffa_dev->dev);
if (ret) {
dev_err(dev, "unable to register device %s err=%d\n",
dev_name(dev), ret);
put_device(dev);
return NULL;
}
return ffa_dev;
}
EXPORT_SYMBOL_GPL(ffa_device_register);
void ffa_device_unregister(struct ffa_device *ffa_dev)
{
if (!ffa_dev)
return;
device_unregister(&ffa_dev->dev);
}
EXPORT_SYMBOL_GPL(ffa_device_unregister);
int arm_ffa_bus_init(void)
{
return bus_register(&ffa_bus_type);
}
void arm_ffa_bus_exit(void)
{
ffa_devices_unregister();
bus_unregister(&ffa_bus_type);
ida_destroy(&ffa_bus_id);
}
|
