1 // SPDX-License-Identifier: GPL-2.0
3 * Turris Mox rWTM firmware driver
5 * Copyright (C) 2019 Marek Behun <marek.behun@nic.cz>
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>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
19 #define DRIVER_NAME "turris-mox-rwtm"
22 * The macros and constants below come from Turris Mox's rWTM firmware code.
23 * This firmware is open source and it's sources can be found at
24 * https://gitlab.labs.nic.cz/turris/mox-boot-builder/tree/master/wtmi.
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)
35 MBOX_CMD_GET_RANDOM = 1,
36 MBOX_CMD_BOARD_INFO = 2,
37 MBOX_CMD_ECDSA_PUB_KEY = 3,
42 MBOX_CMD_OTP_READ = 7,
43 MBOX_CMD_OTP_WRITE = 8,
50 struct mbox_client mbox_client;
51 struct mbox_chan *mbox;
52 struct mox_kobject *kobj;
55 struct armada_37xx_rwtm_rx_msg reply;
61 struct completion cmd_done;
63 /* board information */
66 int board_version, ram_size;
67 u8 mac_address1[6], mac_address2[6];
69 /* public key burned in eFuse */
76 struct mox_rwtm *rwtm;
79 static inline struct kobject *rwtm_to_kobj(struct mox_rwtm *rwtm)
81 return &rwtm->kobj->kobj;
84 static inline struct mox_rwtm *to_rwtm(struct kobject *kobj)
86 return container_of(kobj, struct mox_kobject, kobj)->rwtm;
89 static void mox_kobj_release(struct kobject *kobj)
91 kfree(to_rwtm(kobj)->kobj);
94 static struct kobj_type mox_kobj_ktype = {
95 .release = mox_kobj_release,
96 .sysfs_ops = &kobj_sysfs_ops,
99 static int mox_kobj_create(struct mox_rwtm *rwtm)
101 rwtm->kobj = kzalloc(sizeof(*rwtm->kobj), GFP_KERNEL);
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));
111 rwtm->kobj->rwtm = rwtm;
116 #define MOX_ATTR_RO(name, format, cat) \
118 name##_show(struct kobject *kobj, struct kobj_attribute *a, \
121 struct mox_rwtm *rwtm = to_rwtm(kobj); \
122 if (!rwtm->has_##cat) \
124 return sprintf(buf, format, rwtm->name); \
126 static struct kobj_attribute mox_attr_##name = __ATTR_RO(name)
128 MOX_ATTR_RO(serial_number, "%016llX\n", board_info);
129 MOX_ATTR_RO(board_version, "%i\n", board_info);
130 MOX_ATTR_RO(ram_size, "%i\n", board_info);
131 MOX_ATTR_RO(mac_address1, "%pM\n", board_info);
132 MOX_ATTR_RO(mac_address2, "%pM\n", board_info);
133 MOX_ATTR_RO(pubkey, "%s\n", pubkey);
135 static int mox_get_status(enum mbox_cmd cmd, u32 retval)
137 if (MBOX_STS_CMD(retval) != cmd ||
138 MBOX_STS_ERROR(retval) != MBOX_STS_SUCCESS)
140 else if (MBOX_STS_ERROR(retval) == MBOX_STS_FAIL)
141 return -(int)MBOX_STS_VALUE(retval);
143 return MBOX_STS_VALUE(retval);
146 static 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,
156 static void mox_rwtm_rx_callback(struct mbox_client *cl, void *data)
158 struct mox_rwtm *rwtm = dev_get_drvdata(cl->dev);
159 struct armada_37xx_rwtm_rx_msg *msg = data;
162 complete(&rwtm->cmd_done);
165 static void reply_to_mac_addr(u8 *mac, u32 t1, u32 t2)
175 static int mox_get_board_info(struct mox_rwtm *rwtm)
177 struct armada_37xx_rwtm_tx_msg msg;
178 struct armada_37xx_rwtm_rx_msg *reply = &rwtm->reply;
181 msg.command = MBOX_CMD_BOARD_INFO;
182 ret = mbox_send_message(rwtm->mbox, &msg);
186 ret = wait_for_completion_timeout(&rwtm->cmd_done, HZ / 2);
190 ret = mox_get_status(MBOX_CMD_BOARD_INFO, reply->retval);
191 if (ret < 0 && ret != -ENODATA) {
193 } else if (ret == -ENODATA) {
195 "Board does not have manufacturing information burned!\n");
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],
204 reply_to_mac_addr(rwtm->mac_address2, reply->status[6],
206 rwtm->has_board_info = 1;
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);
214 msg.command = MBOX_CMD_ECDSA_PUB_KEY;
215 ret = mbox_send_message(rwtm->mbox, &msg);
219 ret = wait_for_completion_timeout(&rwtm->cmd_done, HZ / 2);
223 ret = mox_get_status(MBOX_CMD_ECDSA_PUB_KEY, reply->retval);
224 if (ret < 0 && ret != -ENODATA) {
226 } else if (ret == -ENODATA) {
227 dev_warn(rwtm->dev, "Board has no public key burned!\n");
229 u32 *s = reply->status;
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]);
241 static int mox_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait)
243 struct mox_rwtm *rwtm = (struct mox_rwtm *) rng->priv;
244 struct armada_37xx_rwtm_tx_msg msg;
250 msg.command = MBOX_CMD_GET_RANDOM;
252 msg.args[1] = rwtm->buf_phys;
253 msg.args[2] = (max + 3) & ~3;
256 if (!mutex_trylock(&rwtm->busy))
259 mutex_lock(&rwtm->busy);
262 ret = mbox_send_message(rwtm->mbox, &msg);
266 ret = wait_for_completion_interruptible(&rwtm->cmd_done);
270 ret = mox_get_status(MBOX_CMD_GET_RANDOM, rwtm->reply.retval);
274 memcpy(data, rwtm->buf, max);
278 mutex_unlock(&rwtm->busy);
282 static int turris_mox_rwtm_probe(struct platform_device *pdev)
284 struct mox_rwtm *rwtm;
285 struct device *dev = &pdev->dev;
288 rwtm = devm_kzalloc(dev, sizeof(*rwtm), GFP_KERNEL);
293 rwtm->buf = dmam_alloc_coherent(dev, PAGE_SIZE, &rwtm->buf_phys,
298 ret = mox_kobj_create(rwtm);
300 dev_err(dev, "Cannot create turris-mox-rwtm kobject!\n");
304 ret = sysfs_create_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
306 dev_err(dev, "Cannot create sysfs files!\n");
310 platform_set_drvdata(pdev, rwtm);
312 mutex_init(&rwtm->busy);
314 rwtm->mbox_client.dev = dev;
315 rwtm->mbox_client.rx_callback = mox_rwtm_rx_callback;
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",
326 init_completion(&rwtm->cmd_done);
328 ret = mox_get_board_info(rwtm);
330 dev_warn(dev, "Cannot read board information: %i\n", ret);
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;
337 ret = devm_hwrng_register(dev, &rwtm->hwrng);
339 dev_err(dev, "Cannot register HWRNG: %i\n", ret);
346 mbox_free_channel(rwtm->mbox);
348 sysfs_remove_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
350 kobject_put(rwtm_to_kobj(rwtm));
354 static int turris_mox_rwtm_remove(struct platform_device *pdev)
356 struct mox_rwtm *rwtm = platform_get_drvdata(pdev);
358 sysfs_remove_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
359 kobject_put(rwtm_to_kobj(rwtm));
360 mbox_free_channel(rwtm->mbox);
365 static const struct of_device_id turris_mox_rwtm_match[] = {
366 { .compatible = "cznic,turris-mox-rwtm", },
370 MODULE_DEVICE_TABLE(of, turris_mox_rwtm_match);
372 static struct platform_driver turris_mox_rwtm_driver = {
373 .probe = turris_mox_rwtm_probe,
374 .remove = turris_mox_rwtm_remove,
377 .of_match_table = turris_mox_rwtm_match,
380 module_platform_driver(turris_mox_rwtm_driver);
382 MODULE_LICENSE("GPL v2");
383 MODULE_DESCRIPTION("Turris Mox rWTM firmware driver");
384 MODULE_AUTHOR("Marek Behun <marek.behun@nic.cz>");