1
2
3
4
5
6
7
8#include <linux/armada-37xx-rwtm-mailbox.h>
9#include <linux/completion.h>
10#include <linux/dma-mapping.h>
11#include <linux/hw_random.h>
12#include <linux/mailbox_client.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/of.h>
16#include <linux/platform_device.h>
17#include <linux/slab.h>
18
19#define DRIVER_NAME "turris-mox-rwtm"
20
21
22
23
24
25
26
27#define MBOX_STS_SUCCESS (0 << 30)
28#define MBOX_STS_FAIL (1 << 30)
29#define MBOX_STS_BADCMD (2 << 30)
30#define MBOX_STS_ERROR(s) ((s) & (3 << 30))
31#define MBOX_STS_VALUE(s) (((s) >> 10) & 0xfffff)
32#define MBOX_STS_CMD(s) ((s) & 0x3ff)
33
34enum mbox_cmd {
35 MBOX_CMD_GET_RANDOM = 1,
36 MBOX_CMD_BOARD_INFO = 2,
37 MBOX_CMD_ECDSA_PUB_KEY = 3,
38 MBOX_CMD_HASH = 4,
39 MBOX_CMD_SIGN = 5,
40 MBOX_CMD_VERIFY = 6,
41
42 MBOX_CMD_OTP_READ = 7,
43 MBOX_CMD_OTP_WRITE = 8,
44};
45
46struct mox_kobject;
47
48struct mox_rwtm {
49 struct device *dev;
50 struct mbox_client mbox_client;
51 struct mbox_chan *mbox;
52 struct mox_kobject *kobj;
53 struct hwrng hwrng;
54
55 struct armada_37xx_rwtm_rx_msg reply;
56
57 void *buf;
58 dma_addr_t buf_phys;
59
60 struct mutex busy;
61 struct completion cmd_done;
62
63
64 int has_board_info;
65 u64 serial_number;
66 int board_version, ram_size;
67 u8 mac_address1[6], mac_address2[6];
68
69
70 int has_pubkey;
71 u8 pubkey[135];
72};
73
74struct mox_kobject {
75 struct kobject kobj;
76 struct mox_rwtm *rwtm;
77};
78
79static inline struct kobject *rwtm_to_kobj(struct mox_rwtm *rwtm)
80{
81 return &rwtm->kobj->kobj;
82}
83
84static inline struct mox_rwtm *to_rwtm(struct kobject *kobj)
85{
86 return container_of(kobj, struct mox_kobject, kobj)->rwtm;
87}
88
89static void mox_kobj_release(struct kobject *kobj)
90{
91 kfree(to_rwtm(kobj)->kobj);
92}
93
94static struct kobj_type mox_kobj_ktype = {
95 .release = mox_kobj_release,
96 .sysfs_ops = &kobj_sysfs_ops,
97};
98
99static int mox_kobj_create(struct mox_rwtm *rwtm)
100{
101 rwtm->kobj = kzalloc(sizeof(*rwtm->kobj), GFP_KERNEL);
102 if (!rwtm->kobj)
103 return -ENOMEM;
104
105 kobject_init(rwtm_to_kobj(rwtm), &mox_kobj_ktype);
106 if (kobject_add(rwtm_to_kobj(rwtm), firmware_kobj, "turris-mox-rwtm")) {
107 kobject_put(rwtm_to_kobj(rwtm));
108 return -ENXIO;
109 }
110
111 rwtm->kobj->rwtm = rwtm;
112
113 return 0;
114}
115
116#define MOX_ATTR_RO(name, format, cat) \
117static ssize_t \
118name##_show(struct kobject *kobj, struct kobj_attribute *a, \
119 char *buf) \
120{ \
121 struct mox_rwtm *rwtm = to_rwtm(kobj); \
122 if (!rwtm->has_##cat) \
123 return -ENODATA; \
124 return sprintf(buf, format, rwtm->name); \
125} \
126static struct kobj_attribute mox_attr_##name = __ATTR_RO(name)
127
128MOX_ATTR_RO(serial_number, "%016llX\n", board_info);
129MOX_ATTR_RO(board_version, "%i\n", board_info);
130MOX_ATTR_RO(ram_size, "%i\n", board_info);
131MOX_ATTR_RO(mac_address1, "%pM\n", board_info);
132MOX_ATTR_RO(mac_address2, "%pM\n", board_info);
133MOX_ATTR_RO(pubkey, "%s\n", pubkey);
134
135static int mox_get_status(enum mbox_cmd cmd, u32 retval)
136{
137 if (MBOX_STS_CMD(retval) != cmd ||
138 MBOX_STS_ERROR(retval) != MBOX_STS_SUCCESS)
139 return -EIO;
140 else if (MBOX_STS_ERROR(retval) == MBOX_STS_FAIL)
141 return -(int)MBOX_STS_VALUE(retval);
142 else
143 return MBOX_STS_VALUE(retval);
144}
145
146static const struct attribute *mox_rwtm_attrs[] = {
147 &mox_attr_serial_number.attr,
148 &mox_attr_board_version.attr,
149 &mox_attr_ram_size.attr,
150 &mox_attr_mac_address1.attr,
151 &mox_attr_mac_address2.attr,
152 &mox_attr_pubkey.attr,
153 NULL
154};
155
156static void mox_rwtm_rx_callback(struct mbox_client *cl, void *data)
157{
158 struct mox_rwtm *rwtm = dev_get_drvdata(cl->dev);
159 struct armada_37xx_rwtm_rx_msg *msg = data;
160
161 rwtm->reply = *msg;
162 complete(&rwtm->cmd_done);
163}
164
165static void reply_to_mac_addr(u8 *mac, u32 t1, u32 t2)
166{
167 mac[0] = t1 >> 8;
168 mac[1] = t1;
169 mac[2] = t2 >> 24;
170 mac[3] = t2 >> 16;
171 mac[4] = t2 >> 8;
172 mac[5] = t2;
173}
174
175static int mox_get_board_info(struct mox_rwtm *rwtm)
176{
177 struct armada_37xx_rwtm_tx_msg msg;
178 struct armada_37xx_rwtm_rx_msg *reply = &rwtm->reply;
179 int ret;
180
181 msg.command = MBOX_CMD_BOARD_INFO;
182 ret = mbox_send_message(rwtm->mbox, &msg);
183 if (ret < 0)
184 return ret;
185
186 ret = wait_for_completion_timeout(&rwtm->cmd_done, HZ / 2);
187 if (ret < 0)
188 return ret;
189
190 ret = mox_get_status(MBOX_CMD_BOARD_INFO, reply->retval);
191 if (ret < 0 && ret != -ENODATA) {
192 return ret;
193 } else if (ret == -ENODATA) {
194 dev_warn(rwtm->dev,
195 "Board does not have manufacturing information burned!\n");
196 } else {
197 rwtm->serial_number = reply->status[1];
198 rwtm->serial_number <<= 32;
199 rwtm->serial_number |= reply->status[0];
200 rwtm->board_version = reply->status[2];
201 rwtm->ram_size = reply->status[3];
202 reply_to_mac_addr(rwtm->mac_address1, reply->status[4],
203 reply->status[5]);
204 reply_to_mac_addr(rwtm->mac_address2, reply->status[6],
205 reply->status[7]);
206 rwtm->has_board_info = 1;
207
208 pr_info("Turris Mox serial number %016llX\n",
209 rwtm->serial_number);
210 pr_info(" board version %i\n", rwtm->board_version);
211 pr_info(" burned RAM size %i MiB\n", rwtm->ram_size);
212 }
213
214 msg.command = MBOX_CMD_ECDSA_PUB_KEY;
215 ret = mbox_send_message(rwtm->mbox, &msg);
216 if (ret < 0)
217 return ret;
218
219 ret = wait_for_completion_timeout(&rwtm->cmd_done, HZ / 2);
220 if (ret < 0)
221 return ret;
222
223 ret = mox_get_status(MBOX_CMD_ECDSA_PUB_KEY, reply->retval);
224 if (ret < 0 && ret != -ENODATA) {
225 return ret;
226 } else if (ret == -ENODATA) {
227 dev_warn(rwtm->dev, "Board has no public key burned!\n");
228 } else {
229 u32 *s = reply->status;
230
231 rwtm->has_pubkey = 1;
232 sprintf(rwtm->pubkey,
233 "%06x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x",
234 ret, s[0], s[1], s[2], s[3], s[4], s[5], s[6], s[7],
235 s[8], s[9], s[10], s[11], s[12], s[13], s[14], s[15]);
236 }
237
238 return 0;
239}
240
241static int mox_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait)
242{
243 struct mox_rwtm *rwtm = (struct mox_rwtm *) rng->priv;
244 struct armada_37xx_rwtm_tx_msg msg;
245 int ret;
246
247 if (max > 4096)
248 max = 4096;
249
250 msg.command = MBOX_CMD_GET_RANDOM;
251 msg.args[0] = 1;
252 msg.args[1] = rwtm->buf_phys;
253 msg.args[2] = (max + 3) & ~3;
254
255 if (!wait) {
256 if (!mutex_trylock(&rwtm->busy))
257 return -EBUSY;
258 } else {
259 mutex_lock(&rwtm->busy);
260 }
261
262 ret = mbox_send_message(rwtm->mbox, &msg);
263 if (ret < 0)
264 goto unlock_mutex;
265
266 ret = wait_for_completion_interruptible(&rwtm->cmd_done);
267 if (ret < 0)
268 goto unlock_mutex;
269
270 ret = mox_get_status(MBOX_CMD_GET_RANDOM, rwtm->reply.retval);
271 if (ret < 0)
272 goto unlock_mutex;
273
274 memcpy(data, rwtm->buf, max);
275 ret = max;
276
277unlock_mutex:
278 mutex_unlock(&rwtm->busy);
279 return ret;
280}
281
282static int turris_mox_rwtm_probe(struct platform_device *pdev)
283{
284 struct mox_rwtm *rwtm;
285 struct device *dev = &pdev->dev;
286 int ret;
287
288 rwtm = devm_kzalloc(dev, sizeof(*rwtm), GFP_KERNEL);
289 if (!rwtm)
290 return -ENOMEM;
291
292 rwtm->dev = dev;
293 rwtm->buf = dmam_alloc_coherent(dev, PAGE_SIZE, &rwtm->buf_phys,
294 GFP_KERNEL);
295 if (!rwtm->buf)
296 return -ENOMEM;
297
298 ret = mox_kobj_create(rwtm);
299 if (ret < 0) {
300 dev_err(dev, "Cannot create turris-mox-rwtm kobject!\n");
301 return ret;
302 }
303
304 ret = sysfs_create_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
305 if (ret < 0) {
306 dev_err(dev, "Cannot create sysfs files!\n");
307 goto put_kobj;
308 }
309
310 platform_set_drvdata(pdev, rwtm);
311
312 mutex_init(&rwtm->busy);
313
314 rwtm->mbox_client.dev = dev;
315 rwtm->mbox_client.rx_callback = mox_rwtm_rx_callback;
316
317 rwtm->mbox = mbox_request_channel(&rwtm->mbox_client, 0);
318 if (IS_ERR(rwtm->mbox)) {
319 ret = PTR_ERR(rwtm->mbox);
320 if (ret != -EPROBE_DEFER)
321 dev_err(dev, "Cannot request mailbox channel: %i\n",
322 ret);
323 goto remove_files;
324 }
325
326 init_completion(&rwtm->cmd_done);
327
328 ret = mox_get_board_info(rwtm);
329 if (ret < 0)
330 dev_warn(dev, "Cannot read board information: %i\n", ret);
331
332 rwtm->hwrng.name = DRIVER_NAME "_hwrng";
333 rwtm->hwrng.read = mox_hwrng_read;
334 rwtm->hwrng.priv = (unsigned long) rwtm;
335 rwtm->hwrng.quality = 1024;
336
337 ret = devm_hwrng_register(dev, &rwtm->hwrng);
338 if (ret < 0) {
339 dev_err(dev, "Cannot register HWRNG: %i\n", ret);
340 goto free_channel;
341 }
342
343 return 0;
344
345free_channel:
346 mbox_free_channel(rwtm->mbox);
347remove_files:
348 sysfs_remove_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
349put_kobj:
350 kobject_put(rwtm_to_kobj(rwtm));
351 return ret;
352}
353
354static int turris_mox_rwtm_remove(struct platform_device *pdev)
355{
356 struct mox_rwtm *rwtm = platform_get_drvdata(pdev);
357
358 sysfs_remove_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
359 kobject_put(rwtm_to_kobj(rwtm));
360 mbox_free_channel(rwtm->mbox);
361
362 return 0;
363}
364
365static const struct of_device_id turris_mox_rwtm_match[] = {
366 { .compatible = "cznic,turris-mox-rwtm", },
367 { },
368};
369
370MODULE_DEVICE_TABLE(of, turris_mox_rwtm_match);
371
372static struct platform_driver turris_mox_rwtm_driver = {
373 .probe = turris_mox_rwtm_probe,
374 .remove = turris_mox_rwtm_remove,
375 .driver = {
376 .name = DRIVER_NAME,
377 .of_match_table = turris_mox_rwtm_match,
378 },
379};
380module_platform_driver(turris_mox_rwtm_driver);
381
382MODULE_LICENSE("GPL v2");
383MODULE_DESCRIPTION("Turris Mox rWTM firmware driver");
384MODULE_AUTHOR("Marek Behun <marek.behun@nic.cz>");
385
