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 #define RSU_FW_VERSION_MASK		GENMASK_ULL(15, 0)
24 
25 #define RSU_TIMEOUT	(msecs_to_jiffies(SVC_RSU_REQUEST_TIMEOUT_MS))
26 
27 #define INVALID_RETRY_COUNTER		0xFFFFFFFF
28 
29 typedef void (*rsu_callback)(struct stratix10_svc_client *client,
30 			     struct stratix10_svc_cb_data *data);
31 /**
32  * struct stratix10_rsu_priv - rsu data structure
33  * @chan: pointer to the allocated service channel
34  * @client: active service client
35  * @completion: state for callback completion
36  * @lock: a mutex to protect callback completion state
37  * @status.current_image: address of image currently running in flash
38  * @status.fail_image: address of failed image in flash
39  * @status.version: the version number of RSU firmware
40  * @status.state: the state of RSU system
41  * @status.error_details: error code
42  * @status.error_location: the error offset inside the image that failed
43  * @retry_counter: the current image's retry counter
44  */
45 struct stratix10_rsu_priv {
46 	struct stratix10_svc_chan *chan;
47 	struct stratix10_svc_client client;
48 	struct completion completion;
49 	struct mutex lock;
50 	struct {
51 		unsigned long current_image;
52 		unsigned long fail_image;
53 		unsigned int version;
54 		unsigned int state;
55 		unsigned int error_details;
56 		unsigned int error_location;
57 	} status;
58 	unsigned int retry_counter;
59 };
60 
61 /**
62  * rsu_status_callback() - Status callback from Intel Service Layer
63  * @client: pointer to service client
64  * @data: pointer to callback data structure
65  *
66  * Callback from Intel service layer for RSU status request. Status is
67  * only updated after a system reboot, so a get updated status call is
68  * made during driver probe.
69  */
70 static void rsu_status_callback(struct stratix10_svc_client *client,
71 				struct stratix10_svc_cb_data *data)
72 {
73 	struct stratix10_rsu_priv *priv = client->priv;
74 	struct arm_smccc_res *res = (struct arm_smccc_res *)data->kaddr1;
75 
76 	if (data->status == BIT(SVC_STATUS_RSU_OK)) {
77 		priv->status.version = FIELD_GET(RSU_VERSION_MASK,
78 						 res->a2);
79 		priv->status.state = FIELD_GET(RSU_STATE_MASK, res->a2);
80 		priv->status.fail_image = res->a1;
81 		priv->status.current_image = res->a0;
82 		priv->status.error_location =
83 			FIELD_GET(RSU_ERROR_LOCATION_MASK, res->a3);
84 		priv->status.error_details =
85 			FIELD_GET(RSU_ERROR_DETAIL_MASK, res->a3);
86 	} else {
87 		dev_err(client->dev, "COMMAND_RSU_STATUS returned 0x%lX\n",
88 			res->a0);
89 		priv->status.version = 0;
90 		priv->status.state = 0;
91 		priv->status.fail_image = 0;
92 		priv->status.current_image = 0;
93 		priv->status.error_location = 0;
94 		priv->status.error_details = 0;
95 	}
96 
97 	complete(&priv->completion);
98 }
99 
100 /**
101  * rsu_command_callback() - Update callback from Intel Service Layer
102  * @client: pointer to client
103  * @data: pointer to callback data structure
104  *
105  * Callback from Intel service layer for RSU commands.
106  */
107 static void rsu_command_callback(struct stratix10_svc_client *client,
108 				 struct stratix10_svc_cb_data *data)
109 {
110 	struct stratix10_rsu_priv *priv = client->priv;
111 
112 	if (data->status != BIT(SVC_STATUS_RSU_OK))
113 		dev_err(client->dev, "RSU returned status is %i\n",
114 			data->status);
115 	complete(&priv->completion);
116 }
117 
118 /**
119  * rsu_retry_callback() - Callback from Intel service layer for getting
120  * the current image's retry counter from firmware
121  * @client: pointer to client
122  * @data: pointer to callback data structure
123  *
124  * Callback from Intel service layer for retry counter, which is used by
125  * user to know how many times the images is still allowed to reload
126  * itself before giving up and starting RSU fail-over flow.
127  */
128 static void rsu_retry_callback(struct stratix10_svc_client *client,
129 			       struct stratix10_svc_cb_data *data)
130 {
131 	struct stratix10_rsu_priv *priv = client->priv;
132 	unsigned int *counter = (unsigned int *)data->kaddr1;
133 
134 	if (data->status == BIT(SVC_STATUS_RSU_OK))
135 		priv->retry_counter = *counter;
136 	else
137 		dev_err(client->dev, "Failed to get retry counter %i\n",
138 			data->status);
139 
140 	complete(&priv->completion);
141 }
142 
143 /**
144  * rsu_send_msg() - send a message to Intel service layer
145  * @priv: pointer to rsu private data
146  * @command: RSU status or update command
147  * @arg: the request argument, the bitstream address or notify status
148  * @callback: function pointer for the callback (status or update)
149  *
150  * Start an Intel service layer transaction to perform the SMC call that
151  * is necessary to get RSU boot log or set the address of bitstream to
152  * boot after reboot.
153  *
154  * Returns 0 on success or -ETIMEDOUT on error.
155  */
156 static int rsu_send_msg(struct stratix10_rsu_priv *priv,
157 			enum stratix10_svc_command_code command,
158 			unsigned long arg,
159 			rsu_callback callback)
160 {
161 	struct stratix10_svc_client_msg msg;
162 	int ret;
163 
164 	mutex_lock(&priv->lock);
165 	reinit_completion(&priv->completion);
166 	priv->client.receive_cb = callback;
167 
168 	msg.command = command;
169 	if (arg)
170 		msg.arg[0] = arg;
171 
172 	ret = stratix10_svc_send(priv->chan, &msg);
173 	if (ret < 0)
174 		goto status_done;
175 
176 	ret = wait_for_completion_interruptible_timeout(&priv->completion,
177 							RSU_TIMEOUT);
178 	if (!ret) {
179 		dev_err(priv->client.dev,
180 			"timeout waiting for SMC call\n");
181 		ret = -ETIMEDOUT;
182 		goto status_done;
183 	} else if (ret < 0) {
184 		dev_err(priv->client.dev,
185 			"error %d waiting for SMC call\n", ret);
186 		goto status_done;
187 	} else {
188 		ret = 0;
189 	}
190 
191 status_done:
192 	stratix10_svc_done(priv->chan);
193 	mutex_unlock(&priv->lock);
194 	return ret;
195 }
196 
197 /*
198  * This driver exposes some optional features of the Intel Stratix 10 SoC FPGA.
199  * The sysfs interfaces exposed here are FPGA Remote System Update (RSU)
200  * related. They allow user space software to query the configuration system
201  * status and to request optional reboot behavior specific to Intel FPGAs.
202  */
203 
204 static ssize_t current_image_show(struct device *dev,
205 				  struct device_attribute *attr, char *buf)
206 {
207 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
208 
209 	if (!priv)
210 		return -ENODEV;
211 
212 	return sprintf(buf, "0x%08lx\n", priv->status.current_image);
213 }
214 
215 static ssize_t fail_image_show(struct device *dev,
216 			       struct device_attribute *attr, char *buf)
217 {
218 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
219 
220 	if (!priv)
221 		return -ENODEV;
222 
223 	return sprintf(buf, "0x%08lx\n", priv->status.fail_image);
224 }
225 
226 static ssize_t version_show(struct device *dev, struct device_attribute *attr,
227 			    char *buf)
228 {
229 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
230 
231 	if (!priv)
232 		return -ENODEV;
233 
234 	return sprintf(buf, "0x%08x\n", priv->status.version);
235 }
236 
237 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
238 			  char *buf)
239 {
240 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
241 
242 	if (!priv)
243 		return -ENODEV;
244 
245 	return sprintf(buf, "0x%08x\n", priv->status.state);
246 }
247 
248 static ssize_t error_location_show(struct device *dev,
249 				   struct device_attribute *attr, char *buf)
250 {
251 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
252 
253 	if (!priv)
254 		return -ENODEV;
255 
256 	return sprintf(buf, "0x%08x\n", priv->status.error_location);
257 }
258 
259 static ssize_t error_details_show(struct device *dev,
260 				  struct device_attribute *attr, char *buf)
261 {
262 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
263 
264 	if (!priv)
265 		return -ENODEV;
266 
267 	return sprintf(buf, "0x%08x\n", priv->status.error_details);
268 }
269 
270 static ssize_t retry_counter_show(struct device *dev,
271 				  struct device_attribute *attr, char *buf)
272 {
273 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
274 
275 	if (!priv)
276 		return -ENODEV;
277 
278 	return sprintf(buf, "0x%08x\n", priv->retry_counter);
279 }
280 
281 static ssize_t reboot_image_store(struct device *dev,
282 				  struct device_attribute *attr,
283 				  const char *buf, size_t count)
284 {
285 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
286 	unsigned long address;
287 	int ret;
288 
289 	if (priv == 0)
290 		return -ENODEV;
291 
292 	ret = kstrtoul(buf, 0, &address);
293 	if (ret)
294 		return ret;
295 
296 	ret = rsu_send_msg(priv, COMMAND_RSU_UPDATE,
297 			   address, rsu_command_callback);
298 	if (ret) {
299 		dev_err(dev, "Error, RSU update returned %i\n", ret);
300 		return ret;
301 	}
302 
303 	return count;
304 }
305 
306 static ssize_t notify_store(struct device *dev,
307 			    struct device_attribute *attr,
308 			    const char *buf, size_t count)
309 {
310 	struct stratix10_rsu_priv *priv = dev_get_drvdata(dev);
311 	unsigned long status;
312 	int ret;
313 
314 	if (priv == 0)
315 		return -ENODEV;
316 
317 	ret = kstrtoul(buf, 0, &status);
318 	if (ret)
319 		return ret;
320 
321 	ret = rsu_send_msg(priv, COMMAND_RSU_NOTIFY,
322 			   status, rsu_command_callback);
323 	if (ret) {
324 		dev_err(dev, "Error, RSU notify returned %i\n", ret);
325 		return ret;
326 	}
327 
328 	/* to get the updated state */
329 	ret = rsu_send_msg(priv, COMMAND_RSU_STATUS,
330 			   0, rsu_status_callback);
331 	if (ret) {
332 		dev_err(dev, "Error, getting RSU status %i\n", ret);
333 		return ret;
334 	}
335 
336 	/* only 19.3 or late version FW supports retry counter feature */
337 	if (FIELD_GET(RSU_FW_VERSION_MASK, priv->status.version)) {
338 		ret = rsu_send_msg(priv, COMMAND_RSU_RETRY,
339 				   0, rsu_retry_callback);
340 		if (ret) {
341 			dev_err(dev,
342 				"Error, getting RSU retry %i\n", ret);
343 			return ret;
344 		}
345 	}
346 
347 	return count;
348 }
349 
350 static DEVICE_ATTR_RO(current_image);
351 static DEVICE_ATTR_RO(fail_image);
352 static DEVICE_ATTR_RO(state);
353 static DEVICE_ATTR_RO(version);
354 static DEVICE_ATTR_RO(error_location);
355 static DEVICE_ATTR_RO(error_details);
356 static DEVICE_ATTR_RO(retry_counter);
357 static DEVICE_ATTR_WO(reboot_image);
358 static DEVICE_ATTR_WO(notify);
359 
360 static struct attribute *rsu_attrs[] = {
361 	&dev_attr_current_image.attr,
362 	&dev_attr_fail_image.attr,
363 	&dev_attr_state.attr,
364 	&dev_attr_version.attr,
365 	&dev_attr_error_location.attr,
366 	&dev_attr_error_details.attr,
367 	&dev_attr_retry_counter.attr,
368 	&dev_attr_reboot_image.attr,
369 	&dev_attr_notify.attr,
370 	NULL
371 };
372 
373 ATTRIBUTE_GROUPS(rsu);
374 
375 static int stratix10_rsu_probe(struct platform_device *pdev)
376 {
377 	struct device *dev = &pdev->dev;
378 	struct stratix10_rsu_priv *priv;
379 	int ret;
380 
381 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
382 	if (!priv)
383 		return -ENOMEM;
384 
385 	priv->client.dev = dev;
386 	priv->client.receive_cb = NULL;
387 	priv->client.priv = priv;
388 	priv->status.current_image = 0;
389 	priv->status.fail_image = 0;
390 	priv->status.error_location = 0;
391 	priv->status.error_details = 0;
392 	priv->status.version = 0;
393 	priv->status.state = 0;
394 	priv->retry_counter = INVALID_RETRY_COUNTER;
395 
396 	mutex_init(&priv->lock);
397 	priv->chan = stratix10_svc_request_channel_byname(&priv->client,
398 							  SVC_CLIENT_RSU);
399 	if (IS_ERR(priv->chan)) {
400 		dev_err(dev, "couldn't get service channel %s\n",
401 			SVC_CLIENT_RSU);
402 		return PTR_ERR(priv->chan);
403 	}
404 
405 	init_completion(&priv->completion);
406 	platform_set_drvdata(pdev, priv);
407 
408 	/* get the initial state from firmware */
409 	ret = rsu_send_msg(priv, COMMAND_RSU_STATUS,
410 			   0, rsu_status_callback);
411 	if (ret) {
412 		dev_err(dev, "Error, getting RSU status %i\n", ret);
413 		stratix10_svc_free_channel(priv->chan);
414 	}
415 
416 	/* only 19.3 or late version FW supports retry counter feature */
417 	if (FIELD_GET(RSU_FW_VERSION_MASK, priv->status.version)) {
418 		ret = rsu_send_msg(priv, COMMAND_RSU_RETRY, 0,
419 				   rsu_retry_callback);
420 		if (ret) {
421 			dev_err(dev,
422 				"Error, getting RSU retry %i\n", ret);
423 			stratix10_svc_free_channel(priv->chan);
424 		}
425 	}
426 
427 	return ret;
428 }
429 
430 static int stratix10_rsu_remove(struct platform_device *pdev)
431 {
432 	struct stratix10_rsu_priv *priv = platform_get_drvdata(pdev);
433 
434 	stratix10_svc_free_channel(priv->chan);
435 	return 0;
436 }
437 
438 static struct platform_driver stratix10_rsu_driver = {
439 	.probe = stratix10_rsu_probe,
440 	.remove = stratix10_rsu_remove,
441 	.driver = {
442 		.name = "stratix10-rsu",
443 		.dev_groups = rsu_groups,
444 	},
445 };
446 
447 module_platform_driver(stratix10_rsu_driver);
448 
449 MODULE_LICENSE("GPL v2");
450 MODULE_DESCRIPTION("Intel Remote System Update Driver");
451 MODULE_AUTHOR("Richard Gong <richard.gong@intel.com>");
452