1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018-2019, Intel Corporation
4  */
5 
6 #include <linux/arm-smccc.h>
7 #include <linux/bitfield.h>
8 #include <linux/completion.h>
9 #include <linux/kobject.h>
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/of.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/firmware/intel/stratix10-svc-client.h>
16 #include <linux/string.h>
17 #include <linux/sysfs.h>
18 
19 #define RSU_STATE_MASK			GENMASK_ULL(31, 0)
20 #define RSU_VERSION_MASK		GENMASK_ULL(63, 32)
21 #define RSU_ERROR_LOCATION_MASK		GENMASK_ULL(31, 0)
22 #define RSU_ERROR_DETAIL_MASK		GENMASK_ULL(63, 32)
23 
24 #define RSU_TIMEOUT	(msecs_to_jiffies(SVC_RSU_REQUEST_TIMEOUT_MS))
25 
26 #define INVALID_RETRY_COUNTER		0xFFFFFFFF
27 
28 typedef void (*rsu_callback)(struct stratix10_svc_client *client,
29 			     struct stratix10_svc_cb_data *data);
30 /**
31  * struct stratix10_rsu_priv - rsu data structure
32  * @chan: pointer to the allocated service channel
33  * @client: active service client
34  * @completion: state for callback completion
35  * @lock: a mutex to protect callback completion state
36  * @status.current_image: address of image currently running in flash
37  * @status.fail_image: address of failed image in flash
38  * @status.version: the version number of RSU firmware
39  * @status.state: the state of RSU system
40  * @status.error_details: error code
41  * @status.error_location: the error offset inside the image that failed
42  * @retry_counter: the current image's retry counter
43  */
44 struct stratix10_rsu_priv {
45 	struct stratix10_svc_chan *chan;
46 	struct stratix10_svc_client client;
47 	struct completion completion;
48 	struct mutex lock;
49 	struct {
50 		unsigned long current_image;
51 		unsigned long fail_image;
52 		unsigned int version;
53 		unsigned int state;
54 		unsigned int error_details;
55 		unsigned int error_location;
56 	} status;
57 	unsigned int retry_counter;
58 };
59 
60 /**
61  * rsu_status_callback() - Status callback from Intel Service Layer
62  * @client: pointer to service client
63  * @data: pointer to callback data structure
64  *
65  * Callback from Intel service layer for RSU status request. Status is
66  * only updated after a system reboot, so a get updated status call is
67  * made during driver probe.
68  */
69 static void rsu_status_callback(struct stratix10_svc_client *client,
70 				struct stratix10_svc_cb_data *data)
71 {
72 	struct stratix10_rsu_priv *priv = client->priv;
73 	struct arm_smccc_res *res = (struct arm_smccc_res *)data->kaddr1;
74 
75 	if (data->status == BIT(SVC_STATUS_OK)) {
76 		priv->status.version = FIELD_GET(RSU_VERSION_MASK,
77 						 res->a2);
78 		priv->status.state = FIELD_GET(RSU_STATE_MASK, res->a2);
79 		priv->status.fail_image = res->a1;
80 		priv->status.current_image = res->a0;
81 		priv->status.error_location =
82 			FIELD_GET(RSU_ERROR_LOCATION_MASK, res->a3);
83 		priv->status.error_details =
84 			FIELD_GET(RSU_ERROR_DETAIL_MASK, res->a3);
85 	} else {
86 		dev_err(client->dev, "COMMAND_RSU_STATUS returned 0x%lX\n",
87 			res->a0);
88 		priv->status.version = 0;
89 		priv->status.state = 0;
90 		priv->status.fail_image = 0;
91 		priv->status.current_image = 0;
92 		priv->status.error_location = 0;
93 		priv->status.error_details = 0;
94 	}
95 
96 	complete(&priv->completion);
97 }
98 
99 /**
100  * rsu_command_callback() - Update callback from Intel Service Layer
101  * @client: pointer to client
102  * @data: pointer to callback data structure
103  *
104  * Callback from Intel service layer for RSU commands.
105  */
106 static void rsu_command_callback(struct stratix10_svc_client *client,
107 				 struct stratix10_svc_cb_data *data)
108 {
109 	struct stratix10_rsu_priv *priv = client->priv;
110 
111 	if (data->status == BIT(SVC_STATUS_NO_SUPPORT))
112 		dev_warn(client->dev, "Secure FW doesn't support notify\n");
113 	else if (data->status == BIT(SVC_STATUS_ERROR))
114 		dev_err(client->dev, "Failure, returned status is %lu\n",
115 			BIT(data->status));
116 
117 	complete(&priv->completion);
118 }
119 
120 /**
121  * rsu_retry_callback() - Callback from Intel service layer for getting
122  * the current image's retry counter from firmware
123  * @client: pointer to client
124  * @data: pointer to callback data structure
125  *
126  * Callback from Intel service layer for retry counter, which is used by
127  * user to know how many times the images is still allowed to reload
128  * itself before giving up and starting RSU fail-over flow.
129  */
130 static void rsu_retry_callback(struct stratix10_svc_client *client,
131 			       struct stratix10_svc_cb_data *data)
132 {
133 	struct stratix10_rsu_priv *priv = client->priv;
134 	unsigned int *counter = (unsigned int *)data->kaddr1;
135 
136 	if (data->status == BIT(SVC_STATUS_OK))
137 		priv->retry_counter = *counter;
138 	else if (data->status == BIT(SVC_STATUS_NO_SUPPORT))
139 		dev_warn(client->dev, "Secure FW doesn't support retry\n");
140 	else
141 		dev_err(client->dev, "Failed to get retry counter %lu\n",
142 			BIT(data->status));
143 
144 	complete(&priv->completion);
145 }
146 
147 /**
148  * rsu_send_msg() - send a message to Intel service layer
149  * @priv: pointer to rsu private data
150  * @command: RSU status or update command
151  * @arg: the request argument, the bitstream address or notify status
152  * @callback: function pointer for the callback (status or update)
153  *
154  * Start an Intel service layer transaction to perform the SMC call that
155  * is necessary to get RSU boot log or set the address of bitstream to
156  * boot after reboot.
157  *
158  * Returns 0 on success or -ETIMEDOUT on error.
159  */
160 static int rsu_send_msg(struct stratix10_rsu_priv *priv,
161 			enum stratix10_svc_command_code command,
162 			unsigned long arg,
163 			rsu_callback callback)
164 {
165 	struct stratix10_svc_client_msg msg;
166 	int ret;
167 
168 	mutex_lock(&priv->lock);
169 	reinit_completion(&priv->completion);
170 	priv->client.receive_cb = callback;
171 
172 	msg.command = command;
173 	if (arg)
174 		msg.arg[0] = arg;
175 
176 	ret = stratix10_svc_send(priv->chan, &msg);
177 	if (ret < 0)
178 		goto status_done;
179 
180 	ret = wait_for_completion_interruptible_timeout(&priv->completion,
181 							RSU_TIMEOUT);
182 	if (!ret) {
183 		dev_err(priv->client.dev,
184 			"timeout waiting for SMC call\n");
185 		ret = -ETIMEDOUT;
186 		goto status_done;
187 	} else if (ret < 0) {
188 		dev_err(priv->client.dev,
189 			"error %d waiting for SMC call\n", ret);
190 		goto status_done;
191 	} else {
192 		ret = 0;
193 	}
194 
195 status_done:
196 	stratix10_svc_done(priv->chan);
197 	mutex_unlock(&priv->lock);
198 	return ret;
199 }
200 
201 /*
202  * This driver exposes some optional features of the Intel Stratix 10 SoC FPGA.
203  * The sysfs interfaces exposed here are FPGA Remote System Update (RSU)
204  * related. They allow user space software to query the configuration system
205  * status and to request optional reboot behavior specific to Intel FPGAs.
206  */
207 
208 static ssize_t current_image_show(struct device *dev,
209 				  struct device_attribute *attr, char *buf)
210 {
211 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
212 
213 	if (!priv)
214 		return -ENODEV;
215 
216 	return sprintf(buf, "0x%08lx\n", priv->status.current_image);
217 }
218 
219 static ssize_t fail_image_show(struct device *dev,
220 			       struct device_attribute *attr, char *buf)
221 {
222 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
223 
224 	if (!priv)
225 		return -ENODEV;
226 
227 	return sprintf(buf, "0x%08lx\n", priv->status.fail_image);
228 }
229 
230 static ssize_t version_show(struct device *dev, struct device_attribute *attr,
231 			    char *buf)
232 {
233 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
234 
235 	if (!priv)
236 		return -ENODEV;
237 
238 	return sprintf(buf, "0x%08x\n", priv->status.version);
239 }
240 
241 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
242 			  char *buf)
243 {
244 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
245 
246 	if (!priv)
247 		return -ENODEV;
248 
249 	return sprintf(buf, "0x%08x\n", priv->status.state);
250 }
251 
252 static ssize_t error_location_show(struct device *dev,
253 				   struct device_attribute *attr, char *buf)
254 {
255 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
256 
257 	if (!priv)
258 		return -ENODEV;
259 
260 	return sprintf(buf, "0x%08x\n", priv->status.error_location);
261 }
262 
263 static ssize_t error_details_show(struct device *dev,
264 				  struct device_attribute *attr, char *buf)
265 {
266 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
267 
268 	if (!priv)
269 		return -ENODEV;
270 
271 	return sprintf(buf, "0x%08x\n", priv->status.error_details);
272 }
273 
274 static ssize_t retry_counter_show(struct device *dev,
275 				  struct device_attribute *attr, char *buf)
276 {
277 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
278 
279 	if (!priv)
280 		return -ENODEV;
281 
282 	return sprintf(buf, "0x%08x\n", priv->retry_counter);
283 }
284 
285 static ssize_t reboot_image_store(struct device *dev,
286 				  struct device_attribute *attr,
287 				  const char *buf, size_t count)
288 {
289 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
290 	unsigned long address;
291 	int ret;
292 
293 	if (priv == 0)
294 		return -ENODEV;
295 
296 	ret = kstrtoul(buf, 0, &address);
297 	if (ret)
298 		return ret;
299 
300 	ret = rsu_send_msg(priv, COMMAND_RSU_UPDATE,
301 			   address, rsu_command_callback);
302 	if (ret) {
303 		dev_err(dev, "Error, RSU update returned %i\n", ret);
304 		return ret;
305 	}
306 
307 	return count;
308 }
309 
310 static ssize_t notify_store(struct device *dev,
311 			    struct device_attribute *attr,
312 			    const char *buf, size_t count)
313 {
314 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
315 	unsigned long status;
316 	int ret;
317 
318 	if (priv == 0)
319 		return -ENODEV;
320 
321 	ret = kstrtoul(buf, 0, &status);
322 	if (ret)
323 		return ret;
324 
325 	ret = rsu_send_msg(priv, COMMAND_RSU_NOTIFY,
326 			   status, rsu_command_callback);
327 	if (ret) {
328 		dev_err(dev, "Error, RSU notify returned %i\n", ret);
329 		return ret;
330 	}
331 
332 	/* to get the updated state */
333 	ret = rsu_send_msg(priv, COMMAND_RSU_STATUS,
334 			   0, rsu_status_callback);
335 	if (ret) {
336 		dev_err(dev, "Error, getting RSU status %i\n", ret);
337 		return ret;
338 	}
339 
340 	ret = rsu_send_msg(priv, COMMAND_RSU_RETRY, 0, rsu_retry_callback);
341 	if (ret) {
342 		dev_err(dev, "Error, getting RSU retry %i\n", ret);
343 		return ret;
344 	}
345 
346 	return count;
347 }
348 
349 static DEVICE_ATTR_RO(current_image);
350 static DEVICE_ATTR_RO(fail_image);
351 static DEVICE_ATTR_RO(state);
352 static DEVICE_ATTR_RO(version);
353 static DEVICE_ATTR_RO(error_location);
354 static DEVICE_ATTR_RO(error_details);
355 static DEVICE_ATTR_RO(retry_counter);
356 static DEVICE_ATTR_WO(reboot_image);
357 static DEVICE_ATTR_WO(notify);
358 
359 static struct attribute *rsu_attrs[] = {
360 	&dev_attr_current_image.attr,
361 	&dev_attr_fail_image.attr,
362 	&dev_attr_state.attr,
363 	&dev_attr_version.attr,
364 	&dev_attr_error_location.attr,
365 	&dev_attr_error_details.attr,
366 	&dev_attr_retry_counter.attr,
367 	&dev_attr_reboot_image.attr,
368 	&dev_attr_notify.attr,
369 	NULL
370 };
371 
372 ATTRIBUTE_GROUPS(rsu);
373 
374 static int stratix10_rsu_probe(struct platform_device *pdev)
375 {
376 	struct device *dev = &pdev->dev;
377 	struct stratix10_rsu_priv *priv;
378 	int ret;
379 
380 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
381 	if (!priv)
382 		return -ENOMEM;
383 
384 	priv->client.dev = dev;
385 	priv->client.receive_cb = NULL;
386 	priv->client.priv = priv;
387 	priv->status.current_image = 0;
388 	priv->status.fail_image = 0;
389 	priv->status.error_location = 0;
390 	priv->status.error_details = 0;
391 	priv->status.version = 0;
392 	priv->status.state = 0;
393 	priv->retry_counter = INVALID_RETRY_COUNTER;
394 
395 	mutex_init(&priv->lock);
396 	priv->chan = stratix10_svc_request_channel_byname(&priv->client,
397 							  SVC_CLIENT_RSU);
398 	if (IS_ERR(priv->chan)) {
399 		dev_err(dev, "couldn't get service channel %s\n",
400 			SVC_CLIENT_RSU);
401 		return PTR_ERR(priv->chan);
402 	}
403 
404 	init_completion(&priv->completion);
405 	platform_set_drvdata(pdev, priv);
406 
407 	/* get the initial state from firmware */
408 	ret = rsu_send_msg(priv, COMMAND_RSU_STATUS,
409 			   0, rsu_status_callback);
410 	if (ret) {
411 		dev_err(dev, "Error, getting RSU status %i\n", ret);
412 		stratix10_svc_free_channel(priv->chan);
413 	}
414 
415 	ret = rsu_send_msg(priv, COMMAND_RSU_RETRY, 0, rsu_retry_callback);
416 	if (ret) {
417 		dev_err(dev, "Error, getting RSU retry %i\n", ret);
418 		stratix10_svc_free_channel(priv->chan);
419 	}
420 
421 	return ret;
422 }
423 
424 static int stratix10_rsu_remove(struct platform_device *pdev)
425 {
426 	struct stratix10_rsu_priv *priv = platform_get_drvdata(pdev);
427 
428 	stratix10_svc_free_channel(priv->chan);
429 	return 0;
430 }
431 
432 static struct platform_driver stratix10_rsu_driver = {
433 	.probe = stratix10_rsu_probe,
434 	.remove = stratix10_rsu_remove,
435 	.driver = {
436 		.name = "stratix10-rsu",
437 		.dev_groups = rsu_groups,
438 	},
439 };
440 
441 module_platform_driver(stratix10_rsu_driver);
442 
443 MODULE_LICENSE("GPL v2");
444 MODULE_DESCRIPTION("Intel Remote System Update Driver");
445 MODULE_AUTHOR("Richard Gong <richard.gong@intel.com>");
446